CA2695006A1 - Systems and methods for processing co2 - Google Patents

Abstract

Systems and methods for lowering levels of carbon dioxide and other atmospheric pollutants are provided. Economically viable systems and processes capable of removing vast quantities of carbon dioxide and other atmospheric pollutants from gaseous waste streams and sequestering them in storage-stable forms are also discussed.

Description

CROSS-REFERENCE
[0001] This application claims the benefit of the following applications, each of which is incorporated herein by reference in its entirety:
U.S. Provisional Patent Application No. 61/158,992, filed 10 March 2009, titled "Liquid Absorption of Gaseous Pollutants Using a Flat Jet Reactor";
U.S. Provisional Patent Application No. 61/168,166, filed 9 April 2009, titled "Apparatus, Systems, and Methods for Treating Industrial Waste Gases";
U.S. Provisional Patent Application No.61/178,475, filed 14 May 2009, titled "Apparatus, Systems, and Methods for Treating Industrial Waste Gases";
U.S. Provisional Patent Application No. 61/228,210, filed 24 July 2009, titled "Apparatus, Systems, and Methods for Treating Industrial Waste Gases";
U.S. Provisional Patent Application No. 61/230,042, filed 30 July 2009, titled "Apparatus, Systems, and Methods for Treating Industrial Waste Gases";
U.S. Provisional Patent Application No. 61/239,429, filed 2 September 2009, titled, "Apparatus, Systems, and Methods for Treating Industrial Waste Gases";
U.S. Provisional Patent Application No. 61/178,360, filed 14 May 2009, titled, "Methods and Apparatus for Contacting Gas and Liquid";
U.S. Provisional Patent Application No. 61/221,457, filed 29 June 2009, titled, "Gas-Liquid-Solid Contactor and Precipitator: Apparatus and Methods";
U.S. Provisional Patent Application No. 61/221,63 1, filed 30 June 2009, titled "Gas, Liquid, Solid Contacting: Methods and Apparatus";
U.S. Provisional Patent Application No. 61/223,657, filed 7 July 2009, title "Gas, Liquid, Solid Contacting: Methods and Apparatus";
U.S. Provisional Patent Application No. 61/289,657, filed 23 December 2009, titled "Gas, Liquid, Solid Contacting: Methods and Apparatus";
U.S. Provisional Patent Application No. 61/306,412, filed 19 February 2010, titled "Apparatus, Systems, And Methods For Treating Industrial Waste Gases"; and U.S. Provisional Patent Application No. 61/311,275, filed 5 March 2010, titled "Apparatus, Systems, And Methods For Treating Industrial Waste Gases."

BACKGROUND

[0002] The most concentrated point sources of carbon dioxide and many other atmospheric pollutants (e.g., NOx, SOx, volatile organic compounds ("VOCs"), and particulates) are energy-producing power plants, particularly power plants that produce their power by combusting carbon-based fuels (e.g., coal-fired power -2- Docket No. CLRA-026W0 plants). Considering that world energy demand is expected to increase, and despite continuing growth in non-carbon-based sources of energy, atmospheric levels of carbon dioxide and other combustion products of carbon-based fuels are expected to increase as well. As such, power plants utilizing carbon-based fuels are particularly attractive sites for technologies aimed at lowering emissions of carbon dioxide and other atmospheric pollutants.

[0003] Attempts at lowering emissions of carbon dioxide and other atmospheric pollutants from power plant waste streams have produced many varied technologies, most of which require very large energy inputs to overcome the energy associated with isolating and concentrating diffuse gaseous species. In addition, current technologies and related equipment are inefficient and cost prohibitive. As such, it is important to develop an economically viable technology capable of removing vast quantities of carbon dioxide and other atmospheric pollutants from gaseous waste streams by sequestering carbon dioxide and other atmospheric pollutants in a stable form or by converting it to valuable commodity products.

[0004] In consideration of the foregoing, a significant need exists for systems and methods that efficiently and economically sequester carbon dioxide and other atmospheric pollutants.

SUMMARY

[0005] In some embodiments, the invention provides an apparatus for transferring a component of a gas into a liquid which includes a gas inlet; a chamber configured to contact the liquid and gas; a first liquid introduction unit at a first location within the chamber and a second liquid introduction unit at a second location within the chamber, in which the liquid introduction units are configured to introduce the liquid into the chamber for contact with the gas; a reservoir configured to contain the liquid after it has contacted the gas;
an outlet for the liquid after it has contacted the gas, wherein the inlet, the chamber, the liquid introduction units, the reservoir, and the outlet are operably connected; and at least one of the following features: i) at least one array of shed rows within the chamber, wherein the shed rows are configured to redistribute the flow of the gas as it enters the chamber such that the gas flows axially along the chamber over a greater area of the cross section of the chamber than the gas flow upon entering the chamber, prior to interacting with the shed rows; ii) an anti-foaming device configured to reduce foaming in the reservoir; iii) at least one pump per liquid introduction unit for pumping the liquid through the introduction unit;
iv) configuration of the liquid introduction units such that the direction of the flow of the liquid out of the first unit is different than the direction of flow of the liquid out of the second unit; v) one or more restriction orifice mechanism (release valve) configured to direct liquid flow to at least one of the liquid introduction units, into the gas inlet, or a combination thereof; and vi) varying the area covered by the liquid introduction units, wherein the liquid introduction units comprise atomizing units that create sprays, wherein at least one atomizing unit is configured to create a spray of angle different from that of the other atomizing units. In some embodiments, the apparatus comprises at least two of the features. In some embodiments, the apparatus comprises at least three of the features. In some embodiments, the apparatus comprises at least four of the features. In some -3- Docket No. CLRA-026W0 embodiments, the apparatus comprises at least five of the features. In some embodiments, the apparatus comprises all of the features. In some embodiments, the gas inlet is configured to accept industrial waste gas, compressed ambient air, compressed carbon dioxide, super critical carbon dioxide or any combination thereof. In some embodiments, the gas comprises an industrial waste gas, carbon dioxide that has been previously separated from an industrial waste gas, or any combination thereof.
In some embodiments, the gas comprises one or more of carbon dioxide, nitrogen oxide, and sulfur oxide. In some embodiments, the first liquid introduction unit is located on the lowest level above the inlet of the gas and is oriented to direct the flow of liquid into the chamber in a direction substantially co-current to the direction of gas flow. In some embodiments, the second liquid introduction unit is oriented to direct the flow of liquid into the chamber in a direction substantially countercurrent to the direction of gas flow. In some embodiments, the first liquid introduction unit, the second liquid introduction unit, or both comprise nozzles. In some embodiments, the nozzles comprise dual-fluid nozzles. In some embodiments, the nozzles comprise eductor-jet nozzles. In some embodiments, at least one of the pumps is controlled with a variable frequency drive. In some embodiments, the anti-foaming device comprises a cone situated over the reservoir. In some embodiments, the anti-foaming device further comprises liquid sprays oriented towards the cone. In some embodiments, the apparatus further comprises a liquid recirculation circuit configured to direct the liquid from the reservoir to the one or more of the liquid introduction units. In some embodiments, the apparatus further comprises a demisting level before the gas exits the contacting chamber. In some embodiments, the demisting level comprises a chevron demister, flat-jet sprays, a wet electrostatic precipitator, a packed bed, or any combination thereof. In some embodiments, the liquid provided to the demisting level comprises a different solution from the liquid provided to the liquid introduction units. In some embodiments, the liquid provided to each of the liquid introduction units comprises a different solution. In some embodiments, the liquid provided to the demisting level is a clear liquid. In some embodiments, the liquid provided to the liquid introduction units comprises a slurry. In some embodiments, the apparatus further comprises a comminution station configured to accept slurry from the reservoir and provide processed slurry to the liquid introduction units. In some embodiments, the recirculation circuit comprises the comminution station. In some embodiments, the reservoir is located below the nozzles at the bottom of the contacting chamber. In some embodiments, the apparatus further comprises a precipitation tank operably connected to the contacting chamber.
In some embodiments, the precipitation tank comprises temperature controllers, inlets for addition of pH adjusting agents, agitators, inlets for crystal growth agents, inlets for crystal seeding agents, inlets for settling agents, inlets for flocculants, or any combination thereof. In some embodiments, the apparatus further comprises a precipitate outlet operably connected to the precipitation tank. In some embodiments, the precipitate outlet collects a solid precipitate and a supernatant solution. In some embodiments, the precipitate outlet separates solid precipitate from the supematant solution. In some embodiments, the apparatus further comprises a conduit to provide the solid precipitate to a building materials fabrication station. In some embodiments, the gas inlet is configured to accept a waste gas from an industrial plant. In some embodiments, the gas inlet is configured to -4- Docket No. CLRA-026W0 accept a flue gas from a plant that combusts fossil fuel. In some embodiments, the gas inlet is configured to accept a flue gas from a plant that combusts fossil fuel, further wherein the flue gas has passed through an emission control system prior to being provided to the gas inlet of said apparatus. In some embodiments, the emission control system comprises one or more of i) an electrostatic precipitator to collect particulates; ii) SOx control technology; iii) NOx control technology; iv) physical filtering technology to collect particulates;
or v) mercury control technology. In some embodiments, the sprays of the atomizing units comprise sprays of 60 near the walls of the contacting chamber and sprays of 90 in the inner cross section of the contacting chamber. In some embodiments, the flow of the gas across the shed rows is perpendicular. In some embodiments, the apparatus further comprises packing material, trays, a packed bed, or any combination thereof within said chamber. In some embodiments, the apparatus further comprises a at least one membrane or one microporous membrane within said chamber.

[0006] In some embodiments, the invention provides an apparatus that includes an absorber that includes a bubble column; an inlet for an industrial gas, wherein the industrial gas includes CO2, SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash in an amount equal to a time-averaged original composition, operably connected to the absorber; an inlet for an absorbing solution, wherein the absorbing solution includes an alkaline solution that includes a salt water, particulate material, or both in an absorbing slurry; an outlet for an effluent gas, said gas characterized by being depleted in CO2 and at least one of SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash relative to said original composition of said industrial gas, in which the outlet is operably connected to said absorber; an outlet for absorbing solution that has contacted the industrial gas operably connected to the absorber; and a processing station operably connected to the output, wherein the processing station is configured to obtain at least one of the following saleable products: a building material comprising a CO2 sequestering component, a desalinated water, a potable water, a slurry comprising a CO2 sequestering component, or a solution comprising a CO2 sequestering component, in which the bubble column is configured to produce bubbles of the industrial gas within the absorbing solution such that at least 10% by weight of the carbon dioxide in the industrial gas is transferred to the absorbing solution. In some embodiments, the invention provides an apparatus that includes an absorber comprising a sparging vessel; an inlet for an industrial gas, wherein the industrial gas comprises CO2, SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash in an amount equal to a time-averaged original composition, operably connected to the absorber; an inlet for an absorbing solution, wherein the absorbing solution comprises an alkaline solution comprising a salt water, particulate material, or both in an absorbing slurry;
an outlet for an effluent gas, said gas characterized by being depleted in CO2 and at least one of SOx, NOx, heavy metal, non-COZ acid gas, andlor fly ash relative to said original composition of said industrial gas, wherein the outlet is operably connected to said absorber; an outlet for absorbing solution that has contacted the industrial gas operably connected to the absorber; and a processing station operably connected to the output, wherein the processing station is configured to obtain at least one of the following saleable products: a building material comprising a CO2 sequestering component, a desalinated water, a potable water, a slurry comprising a COZ sequestering -5- Docket No. CLRA-026W0 component, or a solution comprising a CO2 sequestering component, wherein the sparging vessel is configured to produce bubbles of the industrial gas within the absorbing solution such that at least 10% by weight of the carbon dioxide in the industrial gas is transferred to the absorbing solution. In some embodiments, the invention provides an apparatus that includes an absorber that includes a spray tower; an inlet for an industrial gas, wherein the industrial gas comprises COZ, SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash in an amount equal to a time-averaged original composition, operably connected to the absorber; an inlet for an absorbing solution, wherein the absorbing solution includes an alkaline solution, particulate material, or both in an absorbing slurry; an outlet for an effluent gas, said gas characterized by being depleted in COz and at least one of SOx, NOx, heavy metal, non-COZ acid gas, and/or fly ash relative to said original composition of said industrial gas, wherein the outlet is operably connected to said absorber; an outlet for absorbing solution that has contacted the industrial gas operably connected to the absorber; and a processing station operably connected to the output, wherein the processing station is configured to obtain at least one of the following saleable products: a building material comprising a COZ sequestering component, a desalinated water, a potable water, a slurry comprising a CO2 sequestering component, or a solution comprising a CO2 sequestering component, wherein the spray tower is configured to produce streams, droplets, or a combination thereof of the absorbing solution in the industrial gas such that at least 10% by weight of the carbon dioxide in the industrial gas is transferred to the absorbing solution, further wherein the spray tower is configured to operate at a liquid flow rate to gas flow rate ratio (L/G ratio) of between 50 and 5,000 gallons per minute/1000 actual cubic feet. In some embodiments, the invention provides an apparatus that includes an absorber comprising a at least one of a spray tower, packing material, a packed bed, trays, shed rows, or a microporous membrane; an inlet for an industrial gas, wherein the industrial gas comprises CO2, SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash in an amount equal to a time-averaged original composition, operably connected to the absorber; an inlet for an absorbing solution, wherein the absorbing solution comprises an alkaline solution, particulate material, or both in an absorbing slurry; an outlet for an effluent gas, said gas characterized by being depleted in CO2 and at least one of SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash relative to said original composition of said industrial gas, wherein the outlet is operably connected to said absorber; an outlet for absorbing solution that has contacted the industrial gas operably connected to the absorber; and a processing station operably connected to the output, wherein the processing station is configured to obtain at least one of the following saleable products: a building material comprising a CO2 sequestering component, a desalinated water, a potable water, a slurry comprising a COZ
sequestering component, or a solution comprising a CO2 sequestering component, in which the absorber is configured to produce streams, droplets, or a combination thereof of the absorbing solution in the industrial gas such that at least 10% by weight of the carbon dioxide in the industrial gas is transferred to the absorbing solution, and further wherein the absorber is configured to operate at a liquid flow rate to gas flow rate ratio (L/G ratio) of between 50 and 5,000 gallons per minute/1000 actual cubic feet.
In some embodiments, the invention provides an apparatus that includes an absorber that includes a at least one of a spray tower, packing -6- Docket No. CLRA-026W0 material, a packed bed, trays, shed rows, or a microporous membrane; an inlet for an industrial gas, wherein the industrial gas comprises CO2, SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash in an amount equal to a time-averaged original coinposition, operably connected to the absorber; an inlet for an absorbing solution, wherein the absorbing solution includes an alkaline solution, particulate material, or both in an absorbing slurry, wherein said alkaline solution comprises a salt water, a clear solution, or any combination thereof; an outlet for an effluent gas, said gas characterized by being depleted in COZ and at least one of SOx, NOx, heavy metal, non-COZ acid gas, and/or fly ash relative to said original composition of said industrial gas, wherein the outlet is operably connected to said absorber; an outlet for absorbing solution that has contacted the industrial gas operably connected to the absorber; and a processing station operably connected to the output, wherein the processing station is configured to obtain at least one of the following saleable products: a building material comprising a CO? sequestering component, a desalinated water, a potable water, a slurry comprising a COZ sequestering component, or a solution comprising a COZ sequestering component, in which the absorber is configured to produce streams, droplets, or a combination thereof of the absorbing solution in the industrial gas such that at least 10% by weight of the carbon dioxide in the industrial gas is transferred to the absorbing solution. In some embodiments, the invention provides apparatus that includes an absorber that includes a at least one of a spray tower, packing material, a packed bed, trays, shed rows, or a microporous membrane; an inlet for an industrial gas, wherein the industrial gas comprises CO2, SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash in an amount equal to a time-averaged original composition, operably connected to the absorber; an inlet for an absorbing solution, wherein the absorbing solution comprises an alkaline solution, particulate material, or both in an absorbing slurry, wherein said alkaline solution comprises a salt water; an outlet for an effluent gas, said gas characterized by being depleted in CO2 and at least one of SOx, NOx, heavy metal, non-COZ acid gas, and/or fly ash relative to said original composition of said industrial gas, wherein the outlet is operably connected to said absorber; an outlet for absorbing solution that has contacted the industrial gas operably connected to the absorber; and a processing station operably connected to the output, in which the processing station is configured to obtain a saleable product, in which the absorber is configured to produce streams, droplets, or a combination thereof of the absorbing solution in the industrial gas such that at least 10% by weight of the carbon dioxide in the industrial gas is transferred to the absorbing solution. In some embodiments, the inlet for an industrial gas is configured to accept industrial waste gas, combustion flue gas, cement kiln flue gas, compressed carbon dioxide, super critical carbon dioxide, or any combination thereof. In some embodiments, the absorbing solution is contacted with the industrial gas such that the absorbing solution is present as droplets, rivulets, columns of liquid, jet sprays, liquid sheets, neutrally buoyant clouds of solution, or any combination thereof. In some embodiments, the apparatus further comprises atomizing components, comprising: pressure atomizers (nozzles), rotary atomizers, air-assisted atomizers, airblast atomizers, ultrasonic atomizers, ink jet atomizers, MEMS atomizers, electrostatic spray atomizers, dual fluid atomizers, eduction nozzles, or any combination thereof within the contacting chamber. In some embodiments, the salt water in absorbing solution comprises sea water, an -7- Docket No. CLRA-026W0 alkaline brine, a cation rich brine, a synthetic brine, an industrial waste water, an industrial waste brine, or any combination thereof. In some embodiments, the apparatus further comprises a recirculation system. In some embodiments, the recirculation system comprises conduits and pumps to move absorbing solution that has contacted the industrial gas from the outlet for absorbing solution that has contacted the industrial gas, the processing station or both to the inlet for absorbing solution, the atomizing components, or any combination thereof In some embodiments, the recirculation system comprises conduits and pumps to move gas reduced in C02 from the outlet for effluent gas to the inlet for industrial gas, the bubble columns, sparging vessel, or any combination thereof.
[0007] In some embodiments, the invention provides an emissions control system operably connected to a power plant in which the power plant produces energy and an industrial waste gas that includes carbon dioxide, in which the emissions control system is configured to absorb at least 50% of the carbon dioxide from the waste gas and is configured to use less than 30% of the energy generated by the power plant. In some embodiments, the invention provides an emissions control system operably connected to a power plant in which the power plant produces energy and an industrial waste gas that includes oxides of sulfur, in which the emissions control system is configured to absorb at least 90% of the oxides of sulfur from the waste gas and is configured to use less than 30% of the energy generated by the power plant. In some embodiments, the invention provides an emissions control system operably connected to a power plant in which the power plant produces energy and an industrial waste gas that includes carbon dioxide and sulfur oxide, in which the emissions control system is configured to absorb at least 50% of the carbon dioxide and at least 80% of the sulfur oxide from the waste gas, and in which said emissions control system is further configured to use less than 30% of the energy generated by the power plant. In some embodiments, the emissions control system is configured to accept at least 10% of the industrial waste gas from the power plant. In some embodiments, the emissions control system is configured to accept an alkaline solution from an electrochemical system configured to produce a caustic solution. In some embodiments, the electrochemical system comprises an anode, a cathode, and at least one ion-selective membrane between the anode and cathode. In some embodiments, the electrochemical system is configured to operate at a voltage of 2.8V or less applied across the anode and the cathode. In some embodiments, the emissions control system is configured to accept a pH
adjusting agent, wherein the pH adjusting agent comprises an industrial waste, a naturally occurring pH
adjusting agent, a produced pH adjusting agent, or any combination thereof In some embodiments, the emissions control system is configured to operate at a liquid flow rate to gas flow rate ratio (L/G) ranging from 5 to 5,000 gallons per minute/1000 actual cubic feet per minute. In some enlbodiments, the system is configured to operate at a liquid flow rate to gas flow rate ratio (L/G) ranging from 100 to 500 gallons per minute/1000 actual cubic feet per minute.

[0008] Provided herein are systems comprising a precipitation reactor for producing an effluent comprising a precipitation product comprising carbonate, bicarbonate, or a combination thereof, operably connected to a -8- Docket No. CLRA-026W0 liquid-solid separation apparatus for concentrating the precipitation product from the precipitation reactor effluent.

[0009] In one version of the liquid-solid separation apparatus, the liquid-solid separation apparatus comprises a baffle situated such that in operation the baffle deflects the precipitation reactor effluent such that precipitation product descends to a lower region of the liquid-solid separation apparatus and supematant ascends and exits the liquid-solid separation apparatus. In another version of the liquid-solid apparatus, the liquid-solid separation apparatus comprises a spiral channel configured to direct effluent from the precipitation reactor to flow in the spiral channel resulting in concentration of the precipitation product based on size and mass and production of a supematant. Liquid-solid separation apparatus of the systems described herein comprise a precipitation product collector capable of collecting 50% to 100%, 75% to 100%, or 95% to 100% of the precipitation product from the precipitation station.
Additionally, liquid-solid separation apparatus are capable of processing 100 L/min to 20,000 L/min, 5000 L/min to 20,000 L/min, or 10,000 L/min to 20,000 L/min of effluent from the precipitation station.

[0010] Precipitation reactors of the systems described herein may comprise a charging reactor and precipitation station. The charging reactor is capable of removing COZ from an industrial waste gas stream.
Furthermore, the charging reactor may be capable of removing one or more of SOx, NOx, heavy metals, particulates, VOCs, or a combination thereof, from the industrial waste gas steam. The charging reactor comprises a flat jet nozzle coupled to a source of water, wherein the flat jet nozzle is adapted to form a flat jet stream for contacting a gaseous waste stream comprising COz with water from the source of water. The gaseous waste stream comprising CO2 is a waste stream from an industrial plant that burns carbon-based fuels, calcined materials, or a combination thereof. The water provided by the source of water may contain alkaline earth metal ions; in such cases the source of water may be selected from the group selected from fresh water brackish water, seawater, and brine. The precipitation station is operably connected to a source of a pH-raising agent. The pH-raising agent may comprises ash, oxides, hydroxides, or carbonates. The precipitation station is adapted to produce precipitation product comprising carbonate, bicarbonate, or a combination thereof.

[0011] The systems described herein may further comprise an electrochemical cell. The electrochemical cell may be configured to remove protons from the charging station, the precipitation station, or both the charging and the precipitation station.

[0012] Also provided are integrated systems comprising a power plant that combusts carbon-based fuel to produce a waste gas stream comprising carbon dioxide, operably connected to a waste gas-processing system.
The waste gas-processing system comprises a precipitation reactor for producing an effluent comprising a precipitation product comprising carbonate, bicarbonate, or a combination thereof, operably connected to a liquid-solid separation apparatus for concentrating the precipitation product from the precipitation reactor effluent. In one version of the liquid-solid separation apparatus, the liquid-solid separation apparatus comprises a baffle situated such that in operation the baffle deflects the precipitation reactor effluent such that -9- Docket No. CLRA-026W0 precipitation product descends to a lower region of the liquid-solid separation apparatus and supematant ascends and exits the liquid-solid separation apparatus. In another version of the liquid-solid separation apparatus, the liquid-solid separation apparatus comprises a spiral channel configured to direct effluent from the precipitation reactor to flow in the spiral channel resulting in concentration of the precipitation product based on size and mass and production of a supernatant. The waste gas stream further comprises SOx, NOx, heavy metals, VOCs, particulates, or a combination thereof.
100131 Also provided are methods comprising transferring part or all of a gaseous waste stream from an industrial plant comprising carbon dioxide to a precipitation reactor for producing an effluent comprising a precipitation product comprising carbonate, bicarbonate, or a combination thereof; and concentrating the precipitation product from precipitation reactor effluent in a liquid-solid separation apparatus. In one version of the liquid-solid separation apparatus, the effluent is deflected against a baffle within the liquid-solid separation apparatus such that precipitation product descends to a lower region of the liquid-solid separation apparatus and supematant ascends and exits the liquid-solid separation apparatus. In another version of the liquid-solid separation apparatus, the effluent is made to flow in a spiral channel resulting in concentration of the precipitation product based on size and mass, and production of a supematant.
[0014] Methods for sequestering carbon dioxide may be done with any system according to any one of the preceding claims.

DRAWINGS
[0015] The novel features of the invention are set forth with particularity in the appended claims. A better understanding of the features and advantages of the invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which:
[0016] Fig. 1 provides a system of the invention comprising a processor, wherein the processor is configured to process a variety of gases comprising carbon dioxide.
[0017] Fig. 2 provides a system of the invention comprising a processor and a treatment system, wherein the treatment system is configured to treat compositions from the processor.
[0018] Fig. 3 provides a system of the invention comprising a processor and an optional treatment system, wherein the processor comprises a contactor and a reactor.
[0019] Fig. 4 provides a systein of the invention comprising a processor and a treatment system, wherein supernatant from the treatment system may optionally be recirculated to the processor.
[0020] Fig. 5 provides a system of the invention comprising a processor, a treatment system, and an electrochemical system, wherein supernatant from the treatment system may optionally be recirculated to the processor, the electrochemical system, or a combination thereof.
[0021] Fig. 6A provides a schematic diagram of a COZ sequestration method according to one embodiment of the invention.

-1 ~' Docket No. CLRA-026WO

[0022] Fig. 6B provides a schematic diagram of a CO2 sequestration system according to one embodiment of the invention.
[0023] Fig. 6C provides is a schematic of an embodiment of the system.
[0024] Fig. 7 provides a schematic diagram of a CO2 sequestration system according to another embodiment of the invention.
[0025] Fig. 8 provides a diagram of one embodiment of a low-voltage apparatus for producing hydroxide electrochemically.
[0026] Fig. 9 provides a diagram of another embodiment of a low-voltage apparatus for producing hydroxide electrocheniically.
100271 Fig. 10 provides a diagram of another embodiment of a low-voltage apparatus for producing hydroxide electrochemically.
[0028] Fig. 11 is a schematic of an embodiment the apparatus for contacting solid material, liquid, and gas with a tower configuration.
[0029] Fig. 12 is a schematic of the method for contacting solid material, liquid, and gas.
[0030] Fig. 13 is a schematic of an embodiment of the apparatus for contacting solid material, liquid, and gas with a horizontal configuration as seen lengthwise in cross-section.
[0031] Fig. 14 is a schematic of an embodiment of the apparatus for contacting solid material, liquid, and gas with a horizontal configuration as seen end-on in cross-section.
[0032] Fig. 15 is a schematic of an embodiment of the apparatus.
[0033] Fig. 16 is a schematic of an embodiment of the overall apparatus.
[0034] Fig. 17 is a schematic of a portion of an embodiment of the apparatus showing shed row lay out.
[0035] Fig. 18 is a schematic of an embodiment of the apparatus showing a possible arrangement of sprays.
[0036] Fig. 19 is a schematic of an embodiment of the apparatus showing a possible arrangement of sprays.
[0037] Fig. 20 is a schematic of shed row configurations that may be used in some embodiments of the apparatus and system.
[0038] Fig. 21A shows a side view of an embodiment of the invention where liquid droplets and a gas follow a long path about a compartment wherein the gas inlet is at the top of the compartment.
[0039] Fig. 21B shows a top-down cross-sectional view of an embodiment of the invention where liquid droplets and a gas follow a long path about a compartment wherein the gas inlet is at the top of the compartment.

[0040] Fig. 22A shows a side view of an embodiment of the invention where liquid droplets and a gas follow a long path about a coinpartment wherein the gas in] et is at the bottom of the compartment.
[0041] Fig. 22B shows a top-down cross-sectional view of an embodiment of the invention where liquid droplets and a gas follow a long path about a compartment wherein the gas inlet is at the bottom of the compartment.

[0042] Fig. 23 provides a schematic diagram of a gas-liquid or gas-liquid-solid contactor.

-1 1- Docket No. CLRA-026W0 [0043] Fig. 24 provides a schematic diagram of another view of the gas-liquid or gas-liquid-solid contactor of Fig. 23.
[0044] Fig. 25 provides a diagram of an inline monitor.
[0045] Fig. 26 is a schematic of an embodiment of the apparatus showing both vertically and horizontally oriented sections.
[0046] Fig. 27 is a schematic of an embodiment of the apparatus showing both vertically and horizontally oriented sections.
[0047] Fig. 28 is a schematic of an embodiment of the apparatus showing both vertically and horizontally oriented sections with countercurrent solution circulation, with respect to gas flow, in the horizontally oriented section suing pumps.
[0048] Fig. 29 is a schematic of an einbodiment of the apparatus and system, wherein the system is a series of apparatus.
[0049] Fig. 30 is a schematic of an embodiment showing system that is an array of apparatus [0050] Fig. 31 is a schematic of an embodiment showing system that is an array of apparatus.
[0051] Fig. 32 is a schematic of an embodiment of the system.
[0052] Fig. 33 provides a schematic diagram of power plant that is integrated with a COZ sequestration system according to an embodiment of the invention.
[0053] Fig. 34 provides a schematic diagram of a Portland cement plant.
[0054] Fig. 35 provides a schematic diagram of a cement plant co-located with a precipitation plant according to one embodiment of the invention.
[0055] Fig. 36 provides a schematic of a cement plant that does not require a mined limestone feedstock according to one embodiment of the invention.
[0056] Fig. 37 provides a schematic of a system according to one embodiment of the invention.
[0057] Figs. 38, 39, and 40 provide schematics of a system according to one embodiment of the invention.
[0058] Figs. 41 and 42 provide pictures of precipitate of the invention.
[0059] Fig. 43 provides a picture of amorphous precipitate of the invention.
[0060] Fig. 44 provides graphical results of a COZ absorption experiment reported in the Examples section below.
[0061] Fig. 45 shows an embodiment of the invention where creation of the liquid droplets and contacting the liquid droplets with the gas of interest occur in different chambers.
[0062] Fig. 46 shows an embodiment where droplet creation and gas contacting occur in one chamber that is designed to keep coalesced droplets separate from the liquid from which droplets are formed.
[0063] Fig. 47 is a schematic of an embodiment showing an apparatus that utilizes a de-foaming cone and sprays.

-12- Docket No. CLRA-026W0 DESCRIPTION
[0064] Presented herein are systems, apparatus and methods related to efficiently contacting solid material, liquid and gas. The embodiments presented herein represent methods and apparatus for incorporating a gas into a liquid or a slurry or both. In some embodiments where a slurry is presented, the slurry is comprised of a liquid and a solid material component, such that solid inaterial is present throughout contact of the liquid with the gas. By incorporating, what is meant is dissolution and/or absorption of the gas into the liquid or adsorption and/or chemisorption of the gas on the surface of the liquid.
Incorporation of a gas into a liquid is achieved by optimizing contacting conditions. The conditions varied and optimized in the embodiments herein include: the solution chemistry of the liquid; the surface area to volume ratio of the liquid; the ratio of the flow rate of the liquid or slurry and gas (L/G); and the contact time between the liquid and the gas.
Incorporation of a gas into a liquid is desirable for a many reasons, some of which are considered in embodiments herein, including but not limited to the removal of a component of a gas stream (e.g. scrubbing a flue gas) and efficient precipitation of a material from a reaction between a gas and a liquid (e.g. creation of fine solid particulates).
[0065] The methods, apparatus, and systems of the invention may utilize combinations of gas-liquid or gas-liquid-solid technology as described further herein. Contacting methods where liquid or slurry (i.e. absorbing solution) is introduced into a gas may be utilized in which the liquid and/or slurry is introduced as droplets, streams or a combination thereof. Contacting methods where a gas in introduced into a liquid or slurry (i.e.
absorbing solution) may be utilized in which the gas creates bubbles or a foam within the liquid or slurry. In either situation, the parameters may be optimized to incorporate carbon dioxide and at least one of SOx, NOx, a heavy metal, a non-CO2 acid gas or fly ash into the liquid or slurry that make up the absorbing solution. To facilitate this incorporation, structural features such as packing material, packed beds, trays, shed rows, or membranes, including microporous membranes, may be utilized in the methods, apparatus, and systems of the invention. Once the desired components of a gas have been incorporated into an absorbing solution through contact between the solution and gas, the contacted solution may be disposed of by an convenient means that do not make the components removed from the gas available for release into the Earth's atmosphere.
Alternatively, the contacted solution may be subjected to precipitation conditions such that a solid precipitate is formed, and such precipitate and the effluent liquid may be further processed to recover saleable products (e.g. potable water, building materials comprising a COZ-sequestering component).
[0066] The methods, apparatus, and systems of the invention may be applicable to contacting a gas and an absorbing solution in an emission control system that is operably connected to an power plant, such that the flue gas (i.e. industrial waste gas) from the power plant contains carbon dioxide, SOx, NOx, heavy metals, non-carbon dioxide acid gases, and in some cases fly ash. It is desirable to remove the carbon dioxide and at least one of SOx, NOx, heavy metals, non-carbon dioxide acid gases, and in some cases fly ash while using as little of the energy produced by the power plant, such as 30% o of the energy produced by the power plant, to power the emissions control system. The emissions control system encompasses activities and components -13- Docket No. CLRA-026W0 such as, but not limited to, pumping and recirculating absorbing solution, regenerating or recharging absorbing solution, circulating flue gas, removing particulates including fly ash and precipitates, and disposal of any liquid, solid, or slurry that contains the carbon dioxide and at least one of SOx, NOx, heavy metals, non-carbon dioxide acid gases, and in some cases fly ash that was removed from the flue gas. The methods, apparatus, and systems of the invention may supplant other emissions control systems or may be used in conjunction with existing systems that a power plant may have in place, however, in some embodiments, it may not be necessary to have separate COZ and SOx emissions control systems.
[0067] Some embodiments utilize simultaneous comminution, particle size reduction, and mixing of the solid component of the slurry with the liquid component of the slurry. Some embodiments include contacting with gas while simultaneously mixing and reducing the size of the solid particulates. Comminution, or particle size reduction, may serve to inlprove the reactivity of the solid component of the slurry by increasing the surface area of the solid which can participate in reactions as well as by exposing new solid material with each pass of the slurry through the comminution step. Comminution can be accomplished using any suitable apparatus that reduces the size of the solid particulates, including but not limited to, a jet mill, a screw conveyor, a high shear mixer, wet mill, attrition mill, colloid mill, or any combination thereof. In some embodiments, comminution takes place before the initial contact of the slurry with the gas. In some embodiments, comminution takes place after the initial contact of the slurry with the gas during recirculation.
In some embodiments, comminution takes place in a conduit with a screw conveyor while the slurry is also contacted with gas, prior to reaching the contacting chamber.
[0068] Some embodiments utilize high-efficiency gas-liquid contacting methods or apparatus. High-efficiency gas-liquid contacting methods or apparatus have the added advantages of optimized contacting parameters such as: a higher surface area across which incorporation of the gas into the liquid can take place;
the solution chemistry favors the kinetics of incorporating the gas into the liquid; or sufficient residence time is provided either by slowing fluid flow or increasing the path length that the liquid and gas travel while the gas incorporates into the liquid.
[0069] One of the uses of efficient gas-liquid contacting methods and apparatus is to optimize precipitation reactions. Variations in the solution chemistry of the liquid in a gas-liquid contactor affects the ability of the liquid to incorporate the gas. In some embodiments, the chemistry of the liquid (e.g. absorbing solution, contacting mixture) is affected to incorporate gas more efficiently. In some embodiments, the pH of the liquid (e.g. absorbing solution, contacting mixture) allows for simultaneous removal of COZ and SO2 and/or SOx from the gas. In some embodiments, the chemistry of the liquid (e.g. absorbing solution, contacting mixture) does not require a separate (i.e. distinct from the method or steps to remove C02) SOZ and/or SOx removal step. In some embodiments, the pH of the liquid ranges from pH 4 to pH 13.5.
In some embodiments, the pH of the liquid ranges from pH 4 to pH 11. In some embodiments, the pH of the liquid ranges from pH 5 to pH 10. In some embodiments, the pH of the liquid ranges from pH 5.5 to pH 9.5.
In some embodiments, the pH of the liquid is affected by agents added to the solution from which the droplets are made. Agents which -14- Docket No. CLRA-026W0 alter the pH of the liquid include, but are not limited to: naturally occurring pH raising agents, microorganisms and fungi, synthetic cheniical pH raising agents, recovered man-made waste streams, and alkaline solutions produced by electrochemical means.
[0070] Before the invention is described in greater detail, it is to be understood that the invention is not limited to particular embodiments described herein as such embodiments may vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the invention will be limited only by the appended claims.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.
[0071] Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range, is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included in the smaller ranges and are also encompassed within the invention, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the invention.
[0072] Certain ranges are presented herein with numerical values being preceded by the term "about." The term "about" is used herein to provide literal support for the exact number that it precedes, as well as a number that is near to or approximately the number that the term precedes. In determining whether a number is near to or approximately a specifically recited number, the near or approximating unrecited number may be a number, which, in the context in which it is presented, provides the substantial equivalent of the specifically recited number.
[0073] All publications, patents, and patent applications cited in this specification are incorporated herein by reference to the same extent as if each individual publication, patent, or patent application were specifically and individually indicated to be incorporated by reference. Furthermore, each cited publication, patent, or patent application is incorporated herein by reference to disclose and describe the subject matter in connection with which the publications are cited. The citation of any publication is for its disclosure prior to the filing date and should not be construed as an admission that the invention described herein is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided may be different from the actual publication dates, which may need to be independently confirmed.
100741 It is noted that, as used herein and in the appended claims, the singular forms "a", "an", and "the"
include plural references unless the context clearly dictates otherwise. It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as "solely," "only" and the like in connection with the recitation of claim elements, or use of a"negative" limitation.

-1 5- Docket No. CLRA-026W0 [0075] As will be apparent to those of skill in the art upon reading this disclosure, each of the individual embodiments described and illustrated herein has discrete components and features which may be readily separated from or combined with the features of any of the other several embodiments without departing from the scope or spirit of the invention. Any recited method can be carried out in the order of events recited or in any other order, which is logically possible. Although any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the invention, representative illustrative methods and materials are now described.
[0076] The methods and systems of the invention often may utilize processes sununarized by the following chemical reactions:
(1) Combustion of a carbon-containing fuel source in liquid, gas, or solid phase forms gaseous carbon dioxide:

C+Oz(g)--CO,(g) (2) Contacting the source of carbon dioxide with a water source solvates the carbon dioxide to give an aqueous solution of carbon dioxide:
COz (g) _'4 CO2 (aq) (3) Carbon dioxide dissolved in water establishes equilibrium with aqueous carbonic acid:
COz (aq) + H20 _'_+ H2C03 (aq) (4) Carbonic acid is a weak acid which dissociates in two steps, where the equilibrium balance is determined in part by the pH of the solution, with, generally, pHs below 8-9 favoring bicarbonate formation and pHs above 9-10 favoring carbonate formation. In the second step, a hydroxide source may be added to increase alkalinity:
H2C03 + 2 HzO --* H3O' (aq) + HC03 (aq) HCO3- (aq) + OH" (aq) : HzO + C032- (aq) Reaction of elemental metal cations from Group IIA with the carbonate anion forms a metal carbonate precipitate:
mX (aq) + nCO32 ~ X,,,(C03)õ (s) wherein X is any element or combination of elements that can chemically bond with a carbonate group or its multiple and m and n are stoichiometric positive integers.
[0077] In further describing the subject invention, the inethods of CO-, sequestration according to embodiments of the invention are described first in greater detail. Systems that find use in practicing various embodiments of the methods of the invention are then described, followed by compositions that may be produced using methods and systems of the invention.

[0078] In some embodiments, the invention provides a method of CO2 sequestration. In such einbodiments, an amount of COZ may be removed or segregated from an environment, such as the Earth's atmosphere or a -16- Docket No. CLRA-026W0 gaseous waste stream produced by an industrial plant, so that some or all of the COz is no longer present in the environment from which the CO, was removed. For example, COZ sequestration removes COZ or prevents the release of COZ into the atmosphere from the combustion of fuel.
In some embodiments, the CO2 sequestered is in the form of a composition comprising carbonates, bicarbonates, or carbonates and bicarbonates. Such compositions may comprise a solution, a slurry comprising precipitation material, or precipitation material alone or in combination with one or more additional materials for use in or as a building material. For example, a composition of the invention may comprise precipitation material comprising a carbonate compound (e.g., amorphous caleium carbonate, calcite, aragonite, vaterite, etc.). Therefore, in some embodiments, COz sequestration according to aspects of the invention produces compositions (e.g., precipitation material comprising a carbonate compound), wherein at least part of the carbon in the compositions is derived from a fuel used by humans (e.g., a fossil fuel). C02-sequestering methods of the invention produce storage-stable products from an amount of CO-7, such that the COZ from which the product is produced is then sequestered in that product. A storage-stable CO2-sequestering product is a storage-stable composition that incorporates an amount of COz into a storage-stable form, such as an above-ground, underwater, or underground storage-stable form, so that the CO, is no longer present as, or available to be, a gas in the atmosphere. As such, sequestering of CO2 according to methods of the invention results in prevention of COZ gas from entering the atmosphere and allows for long-term storage of COZ in a manner such that CO2 does not become part of the atmosphere.
[0079] Embodiments of methods of the invention comprise small-, neutral- or negative-carbon footprint methods. Carbon neutral methods of the invention comprise methods having a negligible carbon footprint or no carbon footprint. In negative-carbon footprint methods, the amount by weight of CO2 that is sequestered (e.g., through conversion of CO2 to carbonate) by practice of the methods is greater that the amount of CO2 that is generated (e.g., through power production, base production, etc) to practice the methods. In some instances, the amount by weight of CO2 that is sequestered by practicing the methods exceeds the amount by weight of COz that is generated in practicing the methods by 1 to 100%, such as 5 to 100%, including 10 to 95%, 10 to 90%, 10 to 80%, 10 to 70%, 10 to 60%, 10 to 50%, 10 to 40%, 10 to 30%, 10 to 20%, 20 to 95%, 20 to 90%, 20 to 80%, 20 to 70%, 20 to 60%, 20 to 50%, 20 to 40%, 20 to 30%, 30 to 95%, 30 to 90%, 30 to 80%, 30 to 70%, 30 to 60%, 30 to 50%, 30 to 40%, 40 to 95%, 40 to 90%, 40 to 80%, 40 to 70%, 40 to 60%, 40 to 50%, 50 to 95%, 50 to 90%, 50 to 80%, 50 to 70%, 50 to 60%, 60 to 95%, 60 to 90%, 60 to 80%, 60 to 70%, 70 to 95%, 70 to 90%, 70 to 80%, 80 to 95%, 80 to 90%, and 90 to 95%. In some instances, the amount by weight of CO2 that is sequestered by practicing the methods exceeds the amount by weight of COz that is generated in practicing the methods by 5% or more, by 10% or niore, by 15% or more, by 20% or more, by 30% or more, by 40% or more, by 50% or more, by 60% or more, by 70% or more, by 80% or more, by 90%
or more, or by 95% or more.

[0080] In reference to the system of Fig. 1, the invention provides an aqueous-based method for processing a source of carbon dioxide (130) and producing a composition comprising carbonates, bicarbonates, or -17- Docket No. CLRA-026W0 carbonates and bicarbonates, wherein the source of carbon dioxide comprises one or more additional components in addition to carbon dioxide. In such embodiments, the industrial source of carbon dioxide may be sourced, a source of proton-removing agents (140) may be sourced, and each may be provided to processor 110 to be processed (i.e., subjected to suitable conditions for production of the composition comprising carbonates, bicarbonates, or carbonates and bicarbonates). In some embodiments, processing the industrial source of carbon dioxide comprises contacting the source of proton-removing agents in a contactor such as, but not limited to, a gas-liquid contactor or a gas-liquid-solid contactor to produce a carbon dioxide-charged composition, which composition may be a solution or slurry, from an initial aqueous solution or slurry. In some embodiments, the composition comprising carbonates, bicarbonates, or carbonates and bicarbonates may be produced from the carbon dioxide-charged solution or slurry in the contactor. In some embodiments, the carbon dioxide-charged solution or slurry may be provided to a reactor, within which the composition comprising carbonates, bicarbonates, or carbonates and bicarbonates may be produced. In some embodiments, the composition is produced in both the contactor and the reactor. For example, in some embodiments, the contactor may produce an initial composition comprising bicarbonates and the reactor may produce the composition comprising carbonates, bicarbonates, or carbonates and bicarbonates from the initial composition. In some embodiments, methods of the invention may further comprise sourcing a source of divalent cations such as those of alkaline earth metals (e.g., Ca`'+, Mg2+).
In such embodiments, the source of divalent cations may be provided to the source of proton-removing agents or provided directly to the processor. Provided sufficient divalent cations are provided by the source of proton-removing agents, by the source of divalent cations, or by a combination of the foregoing sources, the composition comprising carbonates, bicarbonates, or carbonates and bicarbonates may comprise an isolable precipitation material (e.g., CaCO3, MgCO3, or a composition thereofJ. Whether the composition from the processor comprises an isolable precipitation material or not, the composition may be used directly from the processor (optionally with minimal post-processing) in the manufacture of building materials. In some embodiments, compositions comprising carbonates, bicarbonates, or carbonates and bicarbonates directly from the processor (optiornally with minimal post-processing) may be injected into a subterranean site as described in U.S. Provisional Patent Application No. 61/232,401, filed 7 August 2009, which application is incorporated herein by reference in its entirety.
[0081] In reference to the systems of Figs. 2-5, the invention provides an aqueous-based method for processing a source of carbon dioxide (130) and producing a composition comprising carbonates, bicarbonates, or carbonates and bicarbonates, wherein the source of carbon dioxide comprises one or more additional components in addition to carbon dioxide. In addition to producing compositions as described in reference to Fig. 1, the invention further provides methods for treating compositions comprising carbonates, bicarbonates, or carbonates and bicarbonates. As such. in some embodiments, the invention provides an aqueous-based method for processing a source of carbon dioxide (130) to produce a composition comprising carbonates, bicarbonates, or carbonates and bicarbonates and treating the composition produced. Whether a -1 g- Docket No. CLRA-026WO

processor-produced composition of the invention comprises an isolable precipitation material or not, the composition may be directly provided to a treatment system of the invention for treatment (e.g., concentration, filtration, etc.). In some embodiments, the composition may be provided directly to the treatment system from a contactor, a reactor, or a settling tank of the processor. For example, a processor-produced composition that does not contain an isolable precipitation material may be provided directly to a treatment system for concentration of the composition and production of a supernatant. In another non-limiting example, a processor-produced composition comprising an isolable precipitation material may be provided directly to a treatment system for liquid-solid separation. The processor-produced composition may be provided to any of a number of treatment system sub-systems, which sub-systems include, but are not limited to, dewatering systems, filtration systems, or dewatering systems in combination with filtration systems, wherein treatment systems, or a sub-systems thereof, separate supematant from the composition to produce a concentrated composition (e.g., the concentrated composition is more concentrated with to respect to carbonates, bicarbonates, or carbonates and carbonates).
[0082] With reference to the system of Fig. 3, in some embodiments, the invention provides a method for charging a solution with COZ from an industrial waste gas stream to produce a composition comprising carbonates, bicarbonates, or carbonates and bicarbonates. In such embodiments, the solution may have a pH
ranging from pH 6.5 to pH 14.0 prior to charging the solution with COZ. In some embodiments, the solution may have a pH of at least pH 6.5, pH 7.0, pH 7.5, pH 8.0, pH 8.5, pH 9.0, pH
9.5, pH 10.0, pH 10.5, pH 11.0, pH 11.5 , pH 12.0, pH 12.5, pH 13.0, pH 13.5, or pH 14.0 prior to charging the solution with CO2. The pH of the solution may be increased using any convenient approach including, but not limited to, use of proton-removing agents and electrochemical methods for effecting proton removal. In some embodiments, proton-removing agents may be used to increase the pH of the solution prior to charging the solution with CO2. Such proton-removing agents include, but are not limited to, hydroxides (e.g., NaOH, KOH) and carbonates (e.g., Na2CO3, K2C03). In some embodiments, sodium hydroxide is used to increase the pH of the solution. As such, in some embodiments, the invention provides a method for charging an alkaline solution (e.g., pH > pH
7.0) with CO2 from an industrial waste gas stream to produce a composition comprising carbonates, bicarbonates, or carbonates and bicarbonates.
[0083] In some embodiments, the composition resulting fi=oYn charging the alkaline solution with COZ from an industrial waste source (i.e., the solution comprising carbonates, bicarbonates, or carbonates and bicarbonates) may be a slurry or a substantially clear solution (i.e., substantially free of precipitation material, such as at least 95% or more free) depending upon the cations available in the solution at the time the solution is charged with CO2. As described herein, the solution niay, in some embodimeits, comprise divalent cations such as Ca2+, Mg2+, or a combination thereof at the time the solution is charged with CO2. In such embodiments, the resultant composition may comprise carbonates, bicarbonates, or carbonates and bicarbonates of divalent cations (e.g. precipitation material) resulting in a slurry. Such slurries, for example, may comprise CaCO3, MgCO3, or a combination thereof. The solution may, in some embodiments, comprise -19- Docket No. CLRA-026W0 insufficient divalent cations to form a slurry comprising carbonates, bicarbonates, or carbonates and bicarbonates of divalent cations at the time the solution is charged with CO2.
In such embodiments, the resultant composition may comprise carbonates, bicarbonates, or carbonates and bicarbonates in a substantially clear solution (i.e., substantially free of precipitation material, such as at least 95% or more free) at the time the solution is charged with CO2. In some embodiments, for example, monovalent cations such as Na+, K+, or a combination thereof (optionally by addition of NaOH and/or KOH) may be present in the substantially clear solution at the time the solution is charged with CO2. The composition resulting from charging such a solution with CO2 may comprise, for example, carbonates, bicarbonates, or carbonates and bicarbonates of monovalent cations.
[0084] As such, in some embodiments, the invention provides a method for charging an alkaline solution (e.g., pH > pH 7.0) with CO2 from an industrial waste gas stream to produce a composition comprising carbonates, bicarbonates, or carbonates and bicarbonates, wherein the composition is substantially clear (i.e., substantially free of precipitation material, such as at least 95% or more free). The substantially clear composition may subsequently be contacted with a source of divalent cations (e.g., Ca2+, Mg2+, or a combination thereof) to produce a composition comprising carbonates, bicarbonates, or carbonates and bicarbonates of divalent cations resulting in a slurry. As above, such slurries may comprise CaCO3, MgCO3, or a combination thereof that may be treated as described herein. In a non-limiting example, an alkaline solution comprising NaOH (e.g., NaOH dissolved in freshwater lacking significant divalent cations) may be contacted in a gas-liquid contactor with CO2 from an industrial waste gas stream to produce a composition comprising carbonates, bicarbonates, or carbonates and bicarbonates, wherein the composition is substantially clear due to a lack of precipitation material, which, in turn, is due to the lack of significant divalent cations.
Depending upon the amount of CO2 added (and makeup NaOH, if any), the substantially clear composition may comprise NaOH, NaHCO3, and/or Na2CO3. The substantially clear composition may subsequently be contacted in a reactor outside the gas-liquid contactor with a source of divalent cations (e.g., Ca2+, Mg2+, Sr2+, and the like) to produce a composition comprising carbonates, bicarbonates, or carbonates and bicarbonates of divalent cations (e.g., precipitation material) resulting in a slurry. As such, compositions may comprise CaCO3 and/or MgCO3i and the compositions may be treated as described herein.
For example, the composition may be subjected to liquid-solid separation and the solids manufactured into cement, supplementary cementitious material, fine aggregate, mortar, coarse aggregate, concrete, pozzolan, or a combination thereof.

[0085] With reference to the systems of Figs. 4 and 5, the invention also provides aqueous-based methods of processing a source of carbon dioxide (130) and producing a composition comprising carbonates, bicarbonates, or carbonates and bicarbonates, wherein the source of carbon dioxide comprises one or more additional components in addition to carbon dioxide, and wherein at least a portion of treatment system supernatant is recirculated. For example, in some embodiments, the invention provides a method of treating a waste gas stream comprising CO2 and, optionally, SOx, NOx, and/or Hg in a processer to produce a processed -20- Docket No. CLRA-026W0 waste gas stream (e.g., a clean gas stream suitable for release into the environment), a composition comprising carbonates, bicarbonates, or carbonates and bicarbonates, and an effluent, wherein at least a portion of the effluent is recirculated to the processor. As shown in Figs. 4 and 5, supematant from the treatment system, which may comprise a dewatering system and a filtration system, may be recirculated in a variety of ways. As such, in some embodiments, at least a portion of the supernatant from the dewatering system, the filtration system, or a combination of the dewatering system and the filtration system may be used to process carbon dioxide. The supernatant may be provided to a carbon dioxide-processing system processor.
In such embodiments, the supernatant may be provided to a contactor (e.g., gas-liquid contactor, gas-liquid-solid contactor), to a reactor, to a combination of the contactor and the reactor, or to any other unit or combination of units for processing carbon dioxide. In addition, in some embodiments, at least a portion of the supernatant from the treatment system may be provided to a washing system.
In such embodiments, the supernatant may be used to wash compositions (e.g., precipitation material comprising CaCO3, MgCO3, or a combination thereof) of the invention. For example, the supernatant may be used to wash chloride from carbonate-based precipitation material. With reference to Fig. 5, at least a portion of the treatment system supematant may be provided to an electrochemical system. As such, treatment system supernatant may be used to produce proton-removing agents or effect proton removal for processing carbon dioxide. In some embodiments, at least a portion of the supematant from the treatment system may be provided to a different system or process. For example, at least a portion of the treatment system supematant may be provided to a desalination plant or desalination process such that the treatment system supernatant, which is generally softer (i.e., lower concentration of Ca2+ and/or Mg2+) than other available feeds (e.g., seawater, brine, etc.) after being used to process carbon dioxide, may be desalinated for potable water.
[0086] Recirculation of treatment system supernatant is advantageous as recirculation provides efficient use of available resources; minimal disturbance of surrounding environments; and reduced energy requirements, which reduced energy requirements provide for lower carbon footprints for systems and methods of the invention. When a carbon dioxide-processing system of the invention is operably connected to an industrial plant (e.g., fossil fuel-fired power plant such as coal-fired power plant) and utilizes power generated at the industrial plant, reduced energy requirements provided by recirculation of treatment system supernatant provide for a reduced energy demand. When expressed as a percentage, the energy demand of a given process, apparatus or system is the energy consumed by that process, apparatus or system with respect to the total output for the power plant with which that process, apparatus or system is connected or servicing. A
carbon dioxide-processing system not configured for recirculation (i.e., a carbon-dioxide processing system configured for a once-through process) such as that shown in Fig. 2, may have an energy demand on the industrial plant of at least 10% attributable to continuously pumping a fresh source of alkalinity (e.g., seawater, brine) into the system. In such an example, a 100 MW power plant (e.g., a coal-fired power plant) would need to devote 10 MW of power to the carbon dioxide-processing system for continuously pumping a fresh source of alkalinity into the system. In contrast, a system configured for recirculation such as that shown -21- Docket No. CLRA-026W0 in Fig. 4 or Fig. 5 may have an energy demand on the industrial plant of less than 10%, such as less than 8%, including less than 6%, for example, less than 4% or less than 2%, which energy demand may be attributable to pumping make-up water and recirculating supernatant. Carbon dioxide-processing systems configured for recirculation, may, when compared to systems designed for a once-through process, exhibit a reduction in energy demand of at least 2%, such as at least 5%, including at least 10%, for example, at least 25% or at least 50%. For example, if a carbon dioxide-processing system configured for recirculation consumes 9 MW of power for pumping make-up water and recirculating supematant and a carbon dioxide-processing system designed for a once-through process consumes 10 MW attributable to pumping, then the carbon dioxide-processing system configured for recirculation exhibits a 10% reduction in energy demand. For systems such as those shown in Figs. 4 and 5 (i.e., carbon dioxide-processing systems configured for recirculation), the reduction in the energy demand attributable to pumping and recirculating may also provide a reduction in total energy demand, especially when compared to carbon dioxide-processing systems configured for once-through process. In some embodiments, recirculation provides a reduction in total energy demand of a carbon dioxide-processing system, wherein the reduction is at least 2%, such as at least 4%, including at least 6%, for example at least 8% or at least 10% when compared to total energy demand of a carbon dioxide-processing system configured for once-through process. For example, if a carbon dioxide-processing system configured for recirculation has a 15% energy demand and a carbon dioxide-processing system designed for a once-through process has a 20% energy demand, then the carbon dioxide-processing system configured for recirculation exhibits a 5% reduction in total energy demand. For example, a carbon dioxide-processing system configured for recirculation, wherein recirculation comprises filtration through a filtration unit such as a nanofiltration unit (e.g., to concentrate divalent cations in the retentate and reduce divalent cations in the permeate), may have a reduction in total energy demand of at least 2%, such as at least 4%, including at least 6%, for example at least 8% or at least 10% when compared to a carbon dioxide-processing system configured for once-through process.
[00871 The energy demand of carbon dioxide-processing methods, apparatus, and systems of the invention may be further reduced by efficient use of other resources. In some embodiments, the energy demand of carbon dioxide-processing systems of the invention may be further reduced by efficient use of heat from an industrial source. In some embodiments, for example, heat from the industrial source of carbon dioxide (e.g., flue gas heat from a coal-fired power plant) may be utilized for drying a composition comprising precipitation material comprising carbonates, bicarbonates, or carbonates and bicarbonates.
In such embodiments, a spray dryer may be used for spray drying the composition. For example, low-grade (e.g., 150-200 C) waste heat may be utilized by means of a heat exchanger to evaporatively spray dry the composition comprising the precipitation material. In addition, utilizing heat from the industrial source of carbon dioxide for drying compositions of the invention allows for simultaneous cooling of the industrial source of carbon dioxide (e.g., flue gas from a coal-fired power plant), which enhances dissolution of carbon dioxide, a process which is inversely related to temperature. In some embodiments, the energy demand of carbon dioxide-processing -22- Docket No. CLRA-026W0 systems of the invention may be further reduced by efficient use of pressure.
For example, in some embodiments, carbon dioxide-processing systems of the invention are configured with an energy recovery system. Such energy recovery systems are known, for example, in the art of desalination and operate by means of pressure exchange. In some embodiments, the overall energy demand of the carbon dioxide-processing system may be less than 99.9%, 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, 15%, 10%, 5%, or 3% when capturing and processing 70-90% of the carbon dioxide emitted from an industrial plant (e.g., coal-fired power plant). For example, in some embodiments, the overall energy demand of the carbon dioxide-processing system may be less than 30%, such as less than 20%, including less than 15%, for example, less than 10%, less than 5%, or less than 3% when capturing and processing 70-90%
of the carbon dioxide emitted from an industrial plant (e.g., coal-fired power plant). As such, carbon dioxide-processing systems of the invention configured for recirculation, heat exchange, and/or pressure exchange may reduce the parasitic load on power-providing industrial plants while maintaining carbon dioxide processing capacity.
[0088] Inevitably, recirculation and other methods described herein consume water as water may become part of a composition of the invention (e.g., precipitation material comprising, for example, amorphous calcium carbonate CaCO3=H20; nesquehonite MgCO3=21-120; etc.), may be vaporized by drying (e.g., spray drying) compositions of the invention, or lost in some other part of the process. As such, make-up water may be provided to account for water lost to processing carbon dioxide to produce compositions of the invention (e.g., spray-dried precipitation material). For example, make-up water amounting to less than 700,000 gallons per day may replace water lost to producing, for example, spray-dried precipitation material from flue gas from a 35 MWe coal-fired power plant. Processes requiring only make-up water may be considered zero process water discharge processes (i.e. zero liquid waste processes). In processes in which additional water other than make-up water is used, that water may be sourced from any of the water sources (e.g., seawater, brine, etc.) described herein. In some embodiments, for example, water may be sourced from the power plant cooling stream and returned to that stream in a closed loop system. Processes requiring make-up water and additional process water are considered low process water discharge processes because systems and methods of the invention are designed to efficiently use resources.
[0089] In some embodiments, the invention provides for contacting a volume of an aqueous solution with a source of carbon dioxide to produce a composition comprising carbonates, bicarbonates, or carbonates and bicarbonates, wherein the composition is a solution or slurry. To produce precipitation material comprising carbonates, bicarbonates, or carbonates and bicarbonates, methods of the invention include contacting a volume of a divalent cation-containing aqueous solution with a source of CO2 and subjecting the resultant solution to conditions that facilitate precipitation. Divalent cations may come from any of a number of different sources of divalent cations depending upon availability at a particular location. Such sources include industrial wastes, seawater, brines, hard waters, rocks and minerals (e.g., lime, periclase, material comprising metal silicates such as serpentine and olivine), and any other suitable source.

-23- Docket No. CLRA-026W0 [0090] In some locations, waste streams from various industrial processes (i.e., industrial waste streams) provide for convenient sources of divalent cations (as well as proton-removing agents such as metal hydroxides). Such waste streams include, but are not limited to, mining wastes; ash (e.g., coal ash such as fly ash, bottom ash, boiler slag); slag (e.g. iron slag, phosphorous slag); cement kiln waste (e.g., cement kiln dust); oil refmery/petrochemical refinery waste (e.g. oil field and methane seam brines); coal seam wastes (e.g. gas production brines and coal seam brine); paper processing waste;
water softening waste brine (e.g., ion exchange effluent); silicon processing wastes; agricultural waste; metal finishing waste; high pH textile waste; and caustic sludge. Ash, cement kiln dust, and slag, collectively waste sources of metal oxides, further described in U.S. Patent Application No. 12/486,692, filed 17 June 2009, which is incorporated herein by reference in its entirety, may be used in any combination with material comprising metal silicates, further described in U.S. Patent Application No. 12/501,217, filed 10 July 2009, which is also incorporated herein by reference in its entirety. Any of the divalent cations sources described herein may be mixed and matched for the purpose of practicing the invention. For example, material comprising metal silicates (e.g., magnesium silicate minerals such as olivine, serpentine, etc.) may be combined with any of the sources of divalent cations described herein for the purpose of practicing the invention.
[0091] In some locations, a convenient source of divalent cations for preparation of compositions of the invention (e.g., precipitation material comprising carbonates, bicarbonates, or carbonates and bicarbonates) is water (e.g., an aqueous solution comprising divalent cations such as seawater or brine), which may vary depending upon the particular location at which the invention is practiced.
Suitable aqueous solutions of divalent cations that may be used include solutions comprising one or more divalent cations (e.g., alkaline earth metal cations such as Ca2+ and Mg2+). In some embodiments, the aqueous source of divalent cations comprises alkaline earth metal cations. In some embodiments, the alkaline earth metal cations include calcium, magnesium, or a mixture thereof. In some embodiments, the aqueous solution of divalent cations comprises calcium in amounts ranging from 50 to 50,000 ppm, 50 to 40,000 ppm, 50 to 20,000 ppm, 100 to 10,000 ppm, 200 to 5000 ppm, or 400 to 1000 ppm. In some embodiments, the aqueous solution of divalent cations comprises magnesium in amounts ranging from 50 to 40,000 ppm, 50 to 20,000 ppm, 100 to 10,000 ppm, 200 to 10,000 ppm, 500 to 5000 ppm, or 500 to 2500 ppm. In some embodiments, where Ca2+ and Mg2+
are both present, the ratio of Ca2+ to Mg2+ (i.e., CaZ+:Mg2+) in the aqueous solution of divalent cations is between 1:1 and 1:2.5; 1:2.5 and 1:5; 1:5 and 1:10; 1:10 and 1:25; 1:25 and 1:50; 1:50 and 1:100; 1:100 and 1:150; 1:150 and 1:200; 1:200 and 1:250; 1:250 and 1:500; 1:500 and 1:1000, or a range thereof. For example, in some embodiments, the ratio of Ca2+ to MgZ+ in the aqueous solution of divalent cations is between 1:1 and 1:10; 1:5 and 1:25; 1:10 and 1:50; 1:25 and 1:100; 1:50 and 1:500; or 1:100 and 1:1000. In some embodiments, the ratio of Mg2+ to CaZ+ (i.e., MgZ+:CaZ) in the aqueous solution of divalent cations is between 1:1 and 1:2.5; 1:2.5 and 1:5; 1:5 and 1:10; 1:10 and 1:25; 1:25 and 1:50; 1:50 and 1:100; 1:100 and 1:150; 1:150 and 1:200; 1:200 and 1:250; 1:250 and 1:500; 1:500 and 1:1000, or a range thereof. For -24- Docket No. CLRA-026W0 example, in some embodiments, the ratio of Mg2+ to CaZ+ in the aqueous solution of divalent cations is between 1:1 and 1:10; 1:5 and 1:25; 1:10 and 1:50; 1:25 and 1:100; 1:50 and 1:500; or 1:100 and 1:1000.
[00921 One or more components that are present in the source of divalent cations from which compositions of the invention (e.g., precipitation material) are prepared may be used to identify the source of divalent cations used. These identifying components and the amounts thereof may be referred to "source identifiers" or "markers." For example, if the source of divalent cations is sea water, the source identifiers or markers that may be present in compositions of the invention (e.g., precipitation material) include, but are not limited to, chlorine, sodium, sulfur, potassium, bromine, silicon, strontium, and the like. Such elements may be present in the compositions in any known valency. Any such source identifiers or markers may be present in small amounts ranging from, for example, 20,000 ppm or less, 2000 ppm or less, 200 ppm or less, or 20 ppm or less. In some embodiments, for example, the marker is strontium. In a precipitation material of the invention, strontium may be incorporated into an aragonite lattice, and make up 10,000 ppm or less of the aragonite lattice, ranging in certain embodiments from 3 to 10,000 ppm, such as from 5 to 5000 ppm, including 5 to 1000 ppm, for example, 5 to 500 ppm or 5 to 100 ppm. Source identifiers may vary depending upon the particular source of divalent cations (e.g., saltwater) employed to produce compositions of the invention. In some embodiments, owing at least in part to the source of divalent cations, the calcium carbonate content compositions of the invention (e.g., precipitation material) may be 25% w/w or higher, such as 40% w/w or higher, including 50% w/w or higher, for example, 60% w/w or higher. Such compositions have, in some embodiments, a calcium:magnesium ratio that is influenced by, and therefore reflects, the source of divalent cations from which the composition was produced. In some embodiments, the calcium:magnesium molar ratio ranges from 10:1 to 1:5 Ca:Mg, such as 5:1 to 1:3 Ca:Mg. In some embodiments, the composition is characterized by having a source identifying carbonate:hydroxide compound ratio, wherein this ratio ranges from, for example, 100 to 1, 10 to 1, or 1 to 1.
[00931 The aqueous solution of divalent cations may comprise divalent cations derived from freshwater, brackish water, seawater, or brine (e.g., naturally occurring brines or anthropogenic brines such as geothermal plant wastewaters, desalination plant waste waters, synthetic brines including synthetic brines that include dissolved minerals), as well as other aqueous solutions having a salinity that is greater than that of freshwater, any of which may be naturally occurring or anthropogenic. For convenience in describing the invention, freshwater may be considered to have a salinity of less than 0.5 ppt (parts per thousand). Brackish water may comprise more salt than freshwater, but not as much as salt as seawater.
Brackish water may be considered to have a salinity ranging from about 0.5 to about 35 ppt. Seawater may be water from a sea, an ocean, or any other body of water that has a salinity ranging from about 35 to about 50 ppt.
Brine may have a salinity that is about 50 ppt or greater. As such, brine may be water saturated or nearly saturated with salt. In some embodiments, the water source from which divalent cations are derived is a mineral rich (e.g., calcium-rich and/or magnesium-rich) freshwater source. In some embodiments, the water source from which divalent cations are derived is a naturally occurring saltwater source selected from a sea, an ocean, a lake, a swamp, an -25- Docket No. CLRA-026W0 estuary, a lagoon, a surface brine, a deep brine, an alkaline lake, an inland sea, or the like. In some embodiments, the water source from which divalent cations are derived is a surface brine. In some embodiments, the water source from which divalent cations are derived is a subsurface brine. In some embodiments, the water source from which divalent cations are derived is a deep brine. In some embodiments, the water source from which divalent cations are derived is a Ca-Mg-Na-(K)-Cl; Na-(Ca)-S04-Cl; Mg-Na-(Ca)-S04-Cl; Na-C03-Cl; or Na-C03-SO4-Cl brine. In some embodiments, the water source from which divalent cation are derived is an anthropogenic brine selected from a geothermal plant wastewater or a desalination wastewater. In some embodiriments, the water source may also contain boron present as borates including, but not limited to B033-, B2054 , B3075-, and B4096- among others.
[0094] Freshwater is often a convenient source of divalent cations (e.g., cations of alkaline earth metals such as Ca2+ and Mg2+). Any of a number of suitable freshwater sources may be used, including freshwater sources ranging from sources relatively free of minerals to sources relatively rich in minerals. Mineral-rich freshwater sources may be naturally occurring, including any of a number of hard water sources, lakes, or inland seas.
Some mineral-rich freshwater sources such as alkaline lakes or inland seas (e.g., Lake Van in Turkey) also provide a source of pH-modifying agents. Mineral-rich freshwater sources may also be anthropogenic. For example, a mineral-poor (soft) water may be contacted with a source of divalent cations such as alkaline earth metal cations (e.g., Ca2+, Mg2+, etc.) to produce a mineral-rich water that is suitable for methods and systems described herein. Divalent cations or precursors thereof (e.g. salts, minerals) may be added to freshwater (or any other type of water described herein) using any convenient protocol (e.g., addition of solids, suspensions, or solutions). In some embodiments, divalent cations selected from Ca2+ and Mgz+ are added to freshwater. In some embodiments, monovalent cations selected from Na+ and K+ are added to freshwater. In some embodiments, freshwater comprising Ca2+ is combined with material comprising metal silicates, ash (e.g., fly ash, bottom ash, boiler slag), or products or processed forms thereof, including combinations of the foregoing, yielding a solution comprising calcium and magnesium cations.
[0095] As such, some methods include preparing a source of divalent cations by adding one or more divalent cations (e.g., Ca2+, Mg2+, combinations thereof, etc.) to a source of water.
Sources of magnesium cations include, but are not limited, magnesium hydroxides, magnesium oxides, etc.
Sources of calcium cations include, but are not limited to, calcium hydroxides, calcium oxides, etc. Both naturally occurring and anthropogenic sources of such cations may be employed. Naturally occurring sources of such cations include, but are not limited to mafic minerals (e.g., olivine, serpentine, periodotite, talc, etc.) and the like. Addition of supplementary magnesium cations to the source water (e.g., seawater) prior to producing compositions of the invention increases yields (e.g., yield of precipitation material) as well as affects the composition of such compositions (e.g., precipitation material), providing a means for increasing COZ sequestration by utilizing minerals such as, but not linuted to, olivine, serpentine, and Mg(OH)2 (brucite). The particular cation (e.g., Ca2+, Mg2+, combinations thereof, etc.) source may be naturally occurring or anthropogenic, and may be pure -26- Docket No. CLRA-026W0 with respect to the mineral or impure (e.g., a composition made up of the mineral of interest and other minerals and components).
[0096] Methods of the invention include adding a magnesium cation source to an initial water in a manner sufficient to produce a magnesium to calcium ratio in the water of 3 or higher, e.g., 4 or higher, such as 5 or higher, for example 6 or higher, including 7 or higher. In certain embodiments, the desired magnesium to calcium cation ratio of the water ranges from 3 to 10, such as 4 to 8. Any convenient magnesium cation source may be added to the water to provide the desired magnesium to calcium cation ratio, where specific magnesium cation sources of interest include, but are not limited to, Mg(OH)2, serpentine, olivine, mafic minerals, and ultramafic minerals. The amount of magnesium cation source that is added to the water may vary, e.g., depending upon the specific magnesium cation source and the initial water from which the C02-charged water is produced. In certain embodiments, the amount of magnesium cation that is added to the water ranges from 0.01 to 100.0 grams/liter, such as from 1 to 100 grams/liter of water, including from 5 to 100 grams/liter of water, for example from 5 to 80 grams/liter of water, including from 5 to 50 grams/liter of water. In certain embodiments, the amount of magnesium cation added to the water is sufficient to produce water with a hardness reading of 0.06 grams/liter or more, such as 0.08 grams/liter or more, including 0.1 grams/liter or more as determined a Metrohm Titrator (Metrohm AG, Switzerland) according to manufacturer's instructions. The magnesium cation source may be combined with the water using any convenient protocol, e.g. with agitation, mixing, etc.
[0097] In embodiments where a source of magnesium, calcium, or a combination of magnesium and calcium is added to the water, the source may be in solid form e.g., in the form of large, hard, and often-crystalline particles or agglomerations of particles that are difficult to get into solution. For example, Mg(OH)2 as brucite can be in such a form, as are many minerals useful in embodiments of the invention, such as serpentine, olivine, and other magnesium silicate minerals, as well as cement waste and the like. Any suitable method may be used to introduce divalent cations such as magnesium cations from such sources into aqueous solution in a form suitable for reaction with carbonate to form carbonates of divalent cations. Increasing surface area by reducing particle size is one such method, which can be done by means well known in the art such as ball grinding and jet milling. Jet milling has the further advantage of destroying much of the crystal structure of the substance, enhancing solubility. Also of interest is sonochemistry, where intense sonication may be employed to increase reaction rates by a desired amount, e.g., 106 times or more. The particles, with or without size reduction, may be exposed to conditions which promote aqueous solution, such as exposure to an acid such as HCI, H2S04, or the like; a weak acid or a base may also be used in some embodiments. See, e.g., U.S. Patent Application Publication Nos. 2005/0022847; 2004/0213705;
2005/0018910; 2008/0031801;
and 2007/0217981; European Patent Application Nos. EP1379469 and EP1554031;
and International Patent Application Publication Nos. WO 07/016271 and WO 08/061305, each of which is incorporated herein by reference in its entirety.

-27- Docket No. CLRA-026W0 [0098] In some embodiments the methods and systems of the invention utilize serpentine as a mineral source. Serpentine is an abundant mineral that occurs naturally and may be generally described by the formula of X2_3Si2O5(OH)4, wherein X is selected from the following: Mg, Ca, Fe2+, Fe3+, Ni, Al, Zn, and Mn, the serpentine material being a heterogeneous mixture consisting primarily of magnesium hydroxide and silica. In some embodiments of the invention, serpentine is used not only as a source of magnesium, but also as a source of hydroxide. Thus in some embodiments of the invention, hydroxide is provided for removal of protons from water and/or adjustment of pH by dissolving serpentine; in these embodiments an acid dissolution is not ideal to accelerate dissolution, and other means are used, such as jet milling and/or sonication. It will be appreciated that in a batch or continuous process, the length of time to dissolve the serpentine or other mineral is not critical, as once the process is started at the desired scale, and sufficient time has passed for appropriate levels of dissolution, a continuous stream of dissolved material may be maintained indefinitely. Thus, even if dissolution to the desired level takes days, weeks, months, or even years, once the process has reached the first time point at which desired dissolution has occurred, it may be maintained indefinitely. Prior to the time point at which desired dissolution has occurred, other processes may be used to provide some or all of the magnesium and/or hydroxide to the process.
Serpentine is also a source of iron, which is a useful component of precipitates that are used for, e.g., cements, where iron components are often desired.
[0099] Other examples of silicate-based minerals useful in the invention include, but are not limited to olivine, a natural magnesium-iron silicate ((Mg, Fe)2SiO4), which can also be generally described by the formula X2(SiO4),,, wherein X is selected from Mg, Ca, Fe2+, Fe3+, Ni, Al, Zn, and Mn, and n = 2 or 3; and a calcium silicate, such as wollastonite. The minerals may be used individually or in combination with each other as described in U.S. Patent Application Publication No. 2009/0301352, published 10 December 2009, which is incorporated herein by reference in its entirety. Additionally, the materials may be found in nature or may be manufactured. Examples of industrial by-products include but are not limited to waste cement, calcium-rich fly ash, and cement kiln dust (CKD) as described in U.S. Patent Application Publication No.
2010/0000444, published 7 January 2010, which is incorporated herein by reference in its entirety.
[00100] In some embodiments, an aqueous solution of divalent cations may be obtained from an industrial plant that is also providing a waste gas stream (e.g., combustion gas stream).
For example, in water-cooled industrial plants, such as seawater-cooled industrial plants, water that has been used by an industrial plant for cooling may then be used as water for producing precipitation material. If desired, the water may be cooled prior to entering a precipitation system of the invention. Such approaches may be employed, for example, with once-through cooling systems. For example, a city or agricultural water supply may be employed as a once-through cooling system for an industrial plant. Water from the industrial plant may then be employed for producing precipitation material, wherein output water has a reduced hardness and greater purity.

-28- Docket No. CLRA-026W0 [00101] The aqueous solution of divalent cations may further provide proton-removing agents, which may be expressed as alkalinity or the ability of the divalent cation-containing solution to neutralize acids to the equivalence point of carbonate or bicarbonate. Alkalinity (AT) may be expressed by the following equation AT = [HC03 1T + 2[CO32IT + [B(OH)4 ]T + [OH IT + 2[PO43 ]T + [HP042 ]T +
[S1O(OH)3 ]T - [H+]sws - [HS04 l, wherein "T" indicates the total concentration of the species in the solution as measured. Other species, depending on the source, may contribute to alkalinity as well. The total concentration of the species in solution is in opposition to the free concentration, which takes into account the significant amount of ion pair interactions that occur, for example, in seawater. In accordance with the equation, the aqueous source of divalent cations may have various concentrations of bicarbonate, carbonate, borate, hydroxide, phosphate, biphosphate, and/or silicate, which may contribute to the alkalinity of the aqueous source of divalent cations.
Any type of alkalinity is suitable for the invention. For example, in some embodiments, a source of divalent cations high in borate alkalinity is suitable for the invention. In such embodiments, the source of divalent cations may contain boron present as borates including, but not limited to, BO33-, B2 O54-, B3075", and B4096-among others. In such embodiments, the concentration borate may exceed the concentration of any other species in solution including, for example, carbonate and/or bicarbonate. In some embodiments, the source of divalent cations has at least 10, 100, 500, 1000, 1500, 3000, 5000, or more than 5000 mEq of alkalinity. For example, in some embodiments, the source of divalent cations has between 500 to 1000 mEq of alkalinity.
[00102] In some methods of the invention, the water (such as salt water or mineral rich water) is not contacted with a source of COZ prior to subjecting the water to precipitation conditions. In these methods, the water will have an amount of CO2 associated with it, e.g., in the form of bicarbonate ion, which has been obtained from the environment to which the water has been exposed prior to practice of the method. Subjecting the water to precipitate conditions of the invention results in conversion of this COZ into a storage-stable precipitate, and therefore sequestration of the CO2. When the water subject to processes of the invention is again exposed to its natural environment, such as the atmosphere, more COZ from the atmosphere will be taken up by the water resulting in a net removal of CO7 from the atmosphere and incorporation of a corresponding amount of COZ
into a storage-stable product, where the mineral rich freshwater source may be contacted with a source of CO2, e.g., as described in greater detail below. Embodiments of these methods may be viewed as methods of sequestering CO2 gas directly from the Earth's atmosphere. Embodiments of the methods are efficient for the removal of COz from the Earth's atmosphere. For example, embodiments of the methods are qonfigured to remove COZ from saltwater at a rate of 0.025 M or more, such as 0.05 M or more, including 0.1 M or more per gallon of saltwater.

[00103] In some embodiments, the invention provides for contacting a volume of an absorbing solution (e.g.
aqueous solution) with a source of carbon dioxide to produce a composition comprising carbonates, bicarbonates, or carbonates and bicarbonates, wherein the composition is a solution or slurry. In some -29- Docket No. CLRA-026W0 embodiments, the solution is a slurry comprising a precipitation material comprising carbonates, bicarbonates, or carbonates and bicarbonates. In some embodiments, the precipitation material is produced by subjecting the volume of the aqueous solution to precipitation conditions before, during, or after contact with the source of carbon dioxide. There may be sufficient carbon dioxide in the aqueous solution to produce significant amounts of carbonates, bicarbonates, or carbonates and bicarbonates (e.g., from brine or seawater); however, additional carbon dioxide is generally used. The source of CO2 may be any convenient CO2 source. The source of CO2 may be a gas, a liquid, a solid (e.g., dry ice), a supercritical fluid, or CO2 dissolved in a liquid.
In some embodiments, the CO2 source is a gaseous CO2 source such as a waste gas stream. The gaseous CO2 source may be substantially pure COZ or, as described in more detail below, comprise one or more components in addition to C02, wherein the one or more components comprise one or more additional gases such as SOx (e.g., SO, SO2, SO3), NOx (e.g., NO, NO2), etc., non-gaseous components, or a combination thereof. The waste streams may further comprise VOC (volatile organic compounds), metals (e.g., mercury, arsenic, cadmium, selenium), and particulate matter comprising particles of solid (e.g., fly ash) or liquid suspended in the gas. In some embodiments, the gaseous CO2 source may be a waste gas stream (e.g., exhaust) produced by an active process of an industrial plant. The nature of the industrial plant may vary, the industrial plants including, but not limited to, power plants, chemical processing plants, mechanical processing plants, refineries, cement plants, steel plants, and other industrial plants that produce CO2 as a by-product of fuel combustion or another processing step (e.g., calcination by a cement plant). In some embodiments, for example, the gaseous CO2 source may be flue gas from coal-fired power plant.
[00104] Waste gas streams comprising CO2 include both reducing condition streams (e.g., syngas, shifted syngas, natural gas, hydrogen, and the like) and oxidizing condition streams (e.g., flue gas resulting from combustion). Particular waste gas streams that may be convenient for the invention include oxygen-containing flue gas resulting from combustion (e.g., from coal or another carbon-based fuel with little or no pretreatment of the flue gas), turbo charged boiler product gas, coal gasification product gas, pre-combustion synthesis gas (e.g., such as that formed during coal gasification in power generating plants), shifted coal gasification product gas, anaerobic digester product gas, wellhead natural gas stream, reformed natural gas or methane hydrates, and the like. Combustion gas from any convenient source may be used in methods and systems of the invention. In some embodiments, a combustion gas from a post-combustion effluent stack of an industrial plant such as a power plant, cement plant, and coal processing plant is used.
[00105] Thus, waste gas streams may be produced from a variety of different types of industrial plants.
Suitable waste gas streams for the invention include waste gas streams produced by industrial plants that combust fossil fuels (e.g., coal, oil, natural gas, propane, diesel), biomass, and/or anthropogenic fuel products of naturally occurring organic fuel deposits (e.g., tar sands, heavy oil, oil shale, etc.). In some embodiments, a waste gas stream suitable for systems and methods of the invention is sourced from a coal-fired power plant, such as a pulverized coal power plant, a supercritical coal power plant, a mass burn coal power plant, a fluidized bed coal power plant. In some embodiments, the waste gas stream is sourced from gas or oil-fired -30- Docket No. CLRA-026W0 boiler and steam turbine power plants, gas or oil-fired boiler simple cycle gas turbine power plants, or gas or oil-fired boiler combined cycle gas turbine power plants. In some embodiments, waste gas streams produced by power plants that combust syngas (i.e., gas that is produced by the gasification of organic matter, for example, coal, biomass, etc.) are used. In some embodiments, waste gas streams from integrated gasification combined cycle (IGCC) plants are used. In some embodiments, waste gas streams produced by heat recovery steam generator (HRSG) plants are used in accordance with systems and methods of the invention.
[00106] Waste gas streams comprising CO2 may also result froni other industrial processing. Waste gas streams produced by cement plants are also suitable for systems and methods of the invention. Cement plant waste gas streams include waste gas streams from both wet process and dry process plants, which plants may employ shaft kilns or rotary kilns, and may include pre-calciners. These industrial plants may each burn a single fuel, or may burn two or more fuels sequentially or simultaneously.
Other industrial plants such as smelters and refineries are also useful sources of waste gas streams that include carbon dioxide.
[00107] The gaseous waste stream may be provided by the industrial plant to the C02-processing system of the invention in any convenient manner that conveys the gaseous waste stream.
In some embodiments, the waste gas stream is provided with a gas conveyor (e.g., a duct, pipe, etc.) that runs from a flue or analogous structure of the industrial plant (e.g., a flue or smokestack of the industrial plant) to one or more locations of the C02-processing system. In such embodiments, a line (e.g., a duct, pipe, etc.) may be connected to the flue of the industrial plant such that gas leaving through the flue is conveyed to the appropriate location(s) of the C02-processing system (e.g., processor or a component thereof, such as a gas-liquid contactor or gas-liquid-solid contactor). Depending upon the particular configuration of the C02-processing system, the location of the gas conveyor on the industrial plant may vary, for example, to provide a waste gas stream of a desired temperature. As such, in some embodiments, where a gaseous waste stream having a temperature ranging for 0 C to 2000 C, such as 0 C to 1800 C, including 60 C to 700 C, for example, 100 C to 400 C is desired, the flue gas may be obtained at the exit point of the boiler, gas turbine, kiln, or at any point of the power plant that provides the desired temperature. The gas conveyor may be configured to maintain flue gas at a temperature above the dew point (e.g., 125 C) in order to avoid condensation and related complications.
Other steps may be taken to reduce the adverse impact of condensation and other deleterious effects, such as employing ducting that is stainless steel or fluorocarbon (such as poly(tetrafluoroethylene)) lined such the duct does not rapidly deteriorate.
[00108] Carbon dioxide may be the priinary non-air derived component in waste gas streams. In some embodiments, waste gas streams may comprise carbon dioxide in. amounts ranging from 200 ppm to 1,000,000 ppm, such as 1000 ppm to 200,000 ppm, including 2000 ppm to 200,000 ppn1, for example, 2000 ppm to 180,000 ppm or 2000 ppm to 130,000 ppm. In some embodiments, waste gas streams may comprise carbon dioxide in amounts ranging from 350 ppm to 400,000 ppm. Such amounts of carbon dioxide may be considered time-averaged amounts. For example, in some embodiments, waste gas streams may comprise carbon dioxide in an amount ranging from 40,000 ppm (4%) to 100,000 ppm (10%) depending on the waste -31- Docket No. CLRA-026W0 gas stream (e.g., CO2 from natural gas-fired power plants, furnaces, small boilers, etc.). For example, in some embodiments, waste gas streams may comprise carbon dioxide in an amount ranging from 100,000 ppm (10%) to 150,000 ppm (15%) depending on the waste gas stream (e.g., COz from coal-fired power plants, oil generators, diesel generators, etc.). For example, in some embodiments, waste gas streams may comprise carbon dioxide in an amount ranging from 200,000 ppm (20%) to 400,000 ppm (40%) depending on the waste gas stream (e.g., COZ from cement plant calcination, chemical plants, etc.). For example, in some embodiments, waste gas streams may comprise carbon dioxide in an amount ranging from 900,000 ppm (90%) to 1,000,000 ppm (100%) depending on the waste gas stream (e.g., CO2 from ethanol fermenters, CO2 from steam reforming at refineries, ammonia plants, substitute natural gas (SNG) plants, COZ separated from sour gases, etc.). The concentration of CO2 in a waste gas stream may be decreased by 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, 95% or more, 99% or more, 99.9% or more, or 99.99%. In other words, at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 99%, 99.9%, or 99.99% of the carbon dioxide may be removed from the waste gas stream.
[00109] A portion of the waste gas stream (i.e., not the entire gaseous waste stream) from an industrial plant may be used to produce compositions comprising carbonates, bicarbonates, or carbonates and bicarbonates. In these embodiments, the portion of the waste gas stream that is employed in producing compositions may be 75% or less, such as 60% or less, and including 50% and less of the waste gas stream. In yet other embodiments, most (e.g., 80% or more) of the entire waste gas stream produced by the industrial plant is employed in producing compositions. In these embodiments, 80% or more, such as 90% or more, including 95% or more, up to 100% of the waste gas stream (e.g., flue gas) generated by the source may be employed for producing compositions of the invention.
[00110] In some embodiments of the invention substantially 100% of the COz contained in a flue gas, or a portion of the flue gas, from a power plant may be sequestered as a composition of the invention (e.g., precipitation material comprising one or more stable or metastable minerals).
Such sequestration may be done in a single step or in multiple steps, and may further involve other processes for sequestering CO2 (e.g., as the concentration of CO2 is decreased in the flue gas, more energy-intensive processes that be prohibitive in energy consumption for removing all of the original CO2 in the gas may become practical in removing the final CO2 in the gas). Thus, in some embodiments, the gas entering the power plant (ordinary atmospheric air) may contain a concentration of COZ that is greater than the concentration of CO2 in the flue gas exiting the plant, which flue gas has been treated by the processes and systems of the invention. Hence, in some embodiments, the methods and systems of the invention encompass a method comprising supplying a gas (e.g., atmospheric air) to a power plant, wherein the gas comprises COz;
treating the gas in the power plant (e.g., by combustion of fossil fuel to consume 02) to produce C02, then treating exhaust gas to remove C02;
and releasing the gas from the power plant, wherein the gas released from the power plant has a lower CO2 content than the gas supplied to the power plant. In some embodiments, the gas released from the power -32- Docket No. CLRA-026W0 plant contains at least 10% less C02, or at least 20% less C02, or at least 30% less COz, or at least 40% less C02, or at least 50% less C02, or at least 60% less C02, or at least 70% less C02, or at least 80% less C02, or at least 90% less C02, or at least 95% less C02, or at least 99% less C02, or at least 99.5% less C02, or at least 99.9% less C02, than the gas entering the power plant. In some embodiments, the gas entering the power plant is atmospheric air and the gas exiting the power plant is treated flue gas.
[00111] Although a waste gas stream from an industrial plant offers a relatively concentrated source of CO2 and/or additional components resulting from combustion of fossil fuels, methods and systems of the invention are also applicable to removing combustion gas components from less concentrated sources (e.g., atmospheric air), which contains a much lower concentration of pollutants than, for example, flue gas. Thus, in some embodiments, methods and systems encompass decreasing the concentration of CO2 and/or additional components in atmospheric air by producing compositions of the invention. As with waste gas streams, the concentration of CO2 in a portion of atmospheric air may be decreased by 10%
or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, 95% or more, 99% or more, 99.9% or more, or 99.99%. Such decreases in CO2 may be accomplished with yields as described herein, or with higher or lower yields, and may be accomplished in one processing step or in a series of processing steps.
[001121 In certain embodiments, oxidizing conditions include subjecting the gaseous stream to hydrogen peroxide (H202) or a H202/CH3OH mixture. An exemplary description of systems and methods for oxidizing a C02-containing gaseous stream using hydrogen peroxide can be found in U.S.
Patent 5,670,122, -incorporated by reference herein in its entirety. As described in the '122 patent, a gaseous stream can be treated with hydrogen peroxide for a sufficient time to oxidize components therein, e.g., to convert one or more of nitric oxide (NO), sulfur trioxide (SO3), light hydrocarbons (Cl-C4), carbon monoxide (CO) and mercury to NO2, SO2, CO2 and HgO. The gaseous stream may be treated with a hydrogen peroxide or a H202/CH3OH mixture prior to contacting the gaseous stream with water (e.g., alkaline earth metal ion-containing water in the form of a flat jet stream, spray or droplets, mist, or a combination thereof). In some embodiments, a recovered gaseous stream, recovered after contacting a gaseous stream with water (e.g., alkaline earth metal-containing water), is treated with the H202/CH3OH mixture and reprocessed (i.e., contacted a second time to the water).
[00113J The reaction time of the hydrogen peroxide or H202/CH3OH mixture may be in the range from 0.01 to 5 seconds, e.g., from 0.1 to 2 seconds. The NOz, SO2, CO7, and HgO (and other components of the gaseous stream) can then be removed by absorption into the water, e.g., alkaline earth metal ion-containing water. In certain embodiments, the gas-charged water is then subjected to the precipitation conditions to form a precipitate comprising one or more of the chemical components from the gaseous stream (e.g., NOZ, SOZ, CO2, HgO, etc. ). As such, the invention provides a quick and efficient method of removing a wide variety of chemical components of a gaseous source (e.g., CO2, criteria pollutants, and/or other toxic or environmentally harmful constituents) such that these components are not emitted into the atmosphere in dangerously high -33- Docket No. CLRA-026W0 concentrations. For example, the invention can be used to remove these compounds in flue gases emanating from boilers, furnaces, incinerators, stationary engines, and other systems connected with combustion of various types of fuels.
[00114] The total amount of hydrogen peroxide and methanol used in combination with the gas streams will generally be in the mole ratio from 0.5 to 2.0, but in most applications from 0.9 to 1.5 of the total number of constituents. Hydrogen peroxide can be injected (e.g., in the form of an aqueous solution) at a concentration of 1% to 50%, e.g., from 10 to 30%. Hydrogen peroxide can be also injected as a mixture of H202 solution and methanol. The use of H202 and methanol mixtures are desirable because methanol is very low in cost.
The methanol to H202 ratio should be as high as possible to reduce the cost of the additive, but to satisfy emission requirements.
[00115] The use of hydrogen peroxide in the invention has many advantages. If properly stored, hydrogen peroxide solutions in water are very stable. The use of hydrogen peroxide does not pose any environmental problems since hydrogen peroxide is not itself a source of pollution, and the only reaction by-products are water and oxygen. Therefore, hydrogen peroxide can be used safely in the invention.
[00116] The pH of the water that is contacted with the COz source may vary. In some instances, the pH of the water that is contacted with the CO2 source is acidic, such that the pH is lower than 7, such as 6.5 or lower, 6 or lower, 5.5 or lower, 5 or lower, 4.5 or lower, or 4 or lower. In yet other embodiments, the pH of the water may be neutral to slightly basic, by which is meant that the pH of the water may range from pH 7 to pH 9, such as pH 7 to pH 8.5, including pH 7.5 to pH 8.5.
[00117] In some instances, the water, such as alkaline earth metal ion-containing water (including alkaline solutions or natural saline alkaline waters), is basic when contacted with the CO2 source, such as a carbon dioxide containing gaseous stream. In these instances, while being basic the pH of the water is generally insufficient to cause precipitation of the storage-stable carbon dioxide sequestering product. As such, the pH
may be 9.5 or lower, such as 9.3 or lower, including 9 or lower.
[00118] In some instances, the pH as described above may be maintained at a substantially constant value during contact with the carbon dioxide containing gaseous stream, or the pH
may be manipulated to maximize CO2 absorption while minimizing base consumption or other means of removing protons, such as by starting at a certain pH and gradually causing the pH to rise as CO2 continues to be introduced. In embodiments where the pH is maintained substantially constant, where by "substantially constant" is meant that the magnitude of change in pH during some phase of contact with the carbon dioxide source is 0.75 or less, such as 0.50 or less, including 0.25 or less, such as 0.10 or less. The pH may be maintained at substantially constant value, or manipulated to maximize CO2 absorption but prevent hydroxide precipitation without precipitation, using any convenient approach. In some instances, the pH is maintained at substantially constant value, or manipulated to maximize CO2 absorption without precipitation, during COZ charging of the water by adding a sufficient amount of base to the water in a manner that provides the substantially constant pH. In some cases it is desirable to control the pH to maximize the absorption of carbon dioxide and other -34- Docket No. CLRA-026W0 components from the gaseous stream (e.g. SOx, NOx, heavy metals, other acid gases) without precipitation of solids and without the release of CO2 , from the water (i.e. absorbing solution). Any convenient base or combination of bases may be adding, including but not limited to oxides and hydroxides, such as magnesium hydroxide, where further examples of suitable bases are reviewed below. In yet other instances, the pH may be maintained at substantially constant value, or manipulated to maximize CO2 absorption, through use of electrochemical protocols, such as the protocols described below, so that the pH of the water is electrochemically maintained at the substantially constant value.
Surprisingly, as shown in Example IV, it has been found that it is possible to absorb, e.g., more than 50% of the CO2 contained in a gas comprising 20% CO2 through simple sparging of seawater with addition of base (removal of protons).
[001191 In some embodiments, the methods and systems of the invention are capable of absorbing 5% or more, 10% or more, 15% or more, 20% or more, 25% or more, 30% or more, 35% or more, 40% or more, 45% or more, 50% or more, 55% or more, 60% or more, 65% or more, 70% or more, 75% or more, 80% or more, 85% or more, 90% or more, 95% or more, or 99% or more of the CO2 in a gaseous source of C02, such as an industrial source of C02, e.g., flue gas from a power plant or waste gas from a cement plant. In some embodiments, the methods and systems of the invention are capable of absorbing 50% or more of the COZ in a gaseous source of CO2, such as an industrial source of C02, e.g., flue gas from a power plant or waste gas from a cement plant.
[001201 In some embodiments, the methods and systems of the invention are capable of absorbing more than 20 tons/hour of carbon dioxide into an absorbing solution as averaged over 72 hours of continuous operation.
In some embodiments, the methods and systems of the invention are capable of absorbing more than 40 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the methods and systems of the invention are capable of absorbing more than 60 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the methods and systems of the invention are capable of absorbing more than 70 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the methods and systems of the invention are capable of absorbing more than 80 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the methods and systems of the invention are capable of absorbing more than 90 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the methods and systems of the invention are capable of absorbing more than 100 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the methods and systems of the invention are capable of absorbing more than 110 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the methods and systems of the invention are capable of absorbing more than 120 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the methods and systems of the invention are capable of absorbing more than 130 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the methods and systems of the invention are capable of absorbing more than 140 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the methods and systems of the invention are capable of absorbing more than 150 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the methods and systems of the -35- Docket No. CLRA-026W0 invention are capable of absorbing more than 160 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the methods and systems of the invention are capable of absorbing more than 170 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the methods and systems of the invention are capable of absorbing more than 180 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the methods and systems of the invention are capable of absorbing more than 190 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the methods and systems of the invention are capable of absorbing more than 200 tons/hour of carbon dioxide into an absorbing solution.
[00121] In some embodiments, the invention provides for contacting a volume of an aqueous solution with a source of carbon dioxide to produce a composition comprising carbonates, bicarbonates, or carbonates and bicarbonates, wherein the composition is a solution or slurry. Contacting the aqueous solution with the source of carbon dioxide facilitates dissolution of COZ into the aqueous solution producing carbonic acid, a species in equilibrium with both bicarbonate and carbonate. In order to produce compositions of the invention (e.g., precipitation material comprising carbonates, bicarbonates, or carbonates and bicarbonates), protons are removed from various species (e.g. carbonic acid, bicarbonate, hydronium, etc.) in the aqueous solution to shift the equilibrium toward bicarbonate, carbonate, or somewhere in between.
As protons are removed, more CO2 goes into solution. In some embodiments, proton-removing agents and/or methods are used while contacting an aqueous solution with CO2 to increase CO2 absorption in one phase of the reaction, wherein the pH may remain constant, increase, or even decrease, followed by a rapid removal of protons (e.g., by addition of a base), which, In some embodiments, may cause rapid precipitation of precipitation material. Protons may be removed from the various species (e.g. carbonic acid, bicarbonate, hydronium, etc.) by any convenient approach, including, but not limited to use of naturally occurring proton-removing agents, use of microorganisms and fungi, use of synthetic chemical proton-removing agents, recovery of waste streams from industrial processes, and using electrochemical means.
[00122] Naturally occurring proton-removing agents encompass any proton-removing agents found in the wider environment that may create or have a basic local environment. Some embodiments provide for naturally occurring proton-removing agents including minerals that create basic environments upon addition to solution. Such minerals include, but are not limited to, lime (CaO);
periclase (MgO); iron hydroxide minerals (e.g., goethite and limonite); and volcanic ash. Methods for digestion of such minerals and rocks comprising such minerals are described in U.S. Patent Application No.
12/501,217, filed 10 July 2009, which is incorporated herein by reference in its entirety. Some embodiments provide for using naturally occurring bodies of water as a source proton-removing agents, which bodies of water comprise carbonate, borate, sulfate, or nitrate alkalinity, or some combination thereof. Any alkaline brine (e.g., surface brine, subsurface brine, a deep brine, etc.) is suitable for use in the invention. In some embodiments, a surface brine comprising carbonate alkalinity provides a source of proton-removing agents. Tn some embodiments, a surface brine comprising borate alkalinity provides a source of proton-removing agents. In some embodiments, a subsurface brine comprising carbonate alkalinity provides a source of proton-removing agents. In some -36- Docket No. CLRA-026W0 embodiments, a subsurface brine comprising borate alkalinity provides a source of proton-removing agents.
In some, embodiments, a deep brine comprising carbonate alkalinity provides a source of proton-removing agents. In some embodiments, a deep brine comprising borate alkalinity provides a source of proton-removing agents. Examples of naturally alkaline bodies of water include, but are not limited to surface water sources (e.g. alkaline lakes such as Mono Lake in California) and ground water sources (e.g. basic aquifers such as the deep geologic alkaline aquifers located at Searles Lake in California). Other embodiments provide for use of deposits from dried alkaline bodies of water such as the crust along Lake Natron in Africa's Great Rift Valley.
For additional sources of brines and evaporites, see U.S. Provisional Patent Application No. 61/264,564, filed 25 November 2009, which are incorporated herein by reference in its entirety.
In some embodiments, organisms that excrete basic molecules or solutions in their normal metabolism are used as proton-removing agents. Examples of such organisms are fungi that produce alkaline protease (e.g., the deep-sea fungus Aspergillus ustus with an optimal pH of 9) and bacteria that create alkaline molecules (e.g., cyanobacteria such as Lyngbya sp. from the Atlin wetland in British Columbia, which increases pH from a byproduct of photosynthesis). In some embodiments, organisms are used to produce proton-removing agents, wherein the organisms (e.g., Bacillus pasteurii, which hydrolyzes urea to ammonia) metabolize a contaminant (e.g. urea) to produce proton-removing agents or solutions comprising proton-removing agents (e.g., ammonia, ammonium hydroxide). In some embodiments, organisms are cultured separately from the precipitation reaction mixture, wherein proton-removing agents or solution comprising proton-removing agents are used for addition to the precipitation reaction mixture. In some embodiments, naturally occurring or manufactured enzymes are used in combination with proton-removing agents to invoke precipitation of precipitation material. Carbonic anhydrase, which is an enzyme produced by plants and animals, accelerates transformation of carbonic acid to bicarbonate in aqueous solution. As such, carbonic anhydrase may be used to enhance dissolution of CO2 and accelerate precipitation of precipitation material, as described in further detail herein.
[001231 Chemical agents for effecting proton removal generally refer to synthetic chemical agents that are produced in large quantities and are commercially available. For example, chemical agents for removing protons include, but are not limited to, hydroxides, organic bases, super bases, oxides, ammonia, and carbonates. Hydroxides include chemical species that provide hydroxide anions in solution, including, for example, sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), or magnesium hydroxide (Mg(OH)Z). Organic bases are carbon-containing molecules that are generally nitrogenous bases including primary amines such as methyl amine, secondary amines such as diisopropylamine, tertiary amines such as diisopropylethylamine, aromatic amines such as aniline, heteroaromatics such as pyridine, imidazole, and benzimidazole, and various forms thereof. In some embodiments, an organic base selected from pyridine, methylamine, imidazole, benzimidazole, histidine, and a phosphazene is used to remove protons from various species (e.g., carbonic acid, bicarbonate, hydronium, etc.) for preparation of compositions of the invention. In some embodiments, ammonia is used to raise pH to a level sufficient for preparation of compositions of the invention. Super bases suitable for use as proton--37- Docket No. CLRA-026W0 removing agents include sodium ethoxide, sodium amide (NaNH2), sodium hydride (NaH), butyl lithium, lithium diisopropylamide, lithium diethylamide, and lithium bis(trimethylsilyl)amide. Oxides including, for example, calcium oxide (CaO), magnesium oxide (MgO), strontium oxide (SrO), beryllium oxide (BeO), and barium oxide (BaO) are also suitable proton-removing agents that may be used.
Carbonates for use in the invention include, but are not limited to, sodium carbonate.
[00124] In addition to comprising cations (e.g., Ca2+, Mg2+, etc.) and other suitable metal forms suitable for use in the invention, waste streams from various industrial processes (i.e., industrial waste streams) may provide proton-removing agents. Such waste streams include, but are not limited to, mining wastes; ash (e.g., coal ash such as fly ash, bottom ash, boiler slag); slag (e.g. iron slag, phosphorous slag); cement kiln waste (e.g., cement kiln dust (CKD)); oil refinery/petrochemical refinery waste (e.g. oil field and methane seam brines); coal seam wastes (e.g. gas production brines and coal seam brine);
paper processing waste; water softening waste brine (e.g., ion exchange effluent); silicon processing wastes; agricultural waste; metal fmishing waste; high pH textile waste; and caustic sludge. Mining wastes include any wastes from the extraction of metal or another precious or useful mineral from the earth. In some embodiments, wastes from mining are used to modify pH, wherein the waste is selected from red mud from the Bayer aluminum extraction process; waste from magnesium extraction from seawater (e.g., Mg(OH)2 such as that found in Moss Landing, California); and wastes from mining processes involving leaching. For example, red mud may be used to modify pH as described in U.S. Provisional Patent Application No.
61/161369, filed 18 March 2009 and PCT Application No. PCT/US 10/25970, filed 2 March 2010, titled "Gas Stream Multi-Pollutants Control Systems And Methods" and U.S. Patent Application No. 12/716,235, filed 2 March 2010, titled "Gas Stream Multi-Pollutants Control Systems And Methods", which are incorporated herein by reference in their entirety. Red mud, depending on processing conditions and source material (e.g., bauxite) might comprise Fe203, A1203, Si02, Na20, CaO, Ti02, K20, MgO, C02, S20, MnO2, P205, each of which species are loosely listed in order from most abundant to least abundant, and each of which species are expressed as oxides for convenience. Coal ash, cement kiln dust, and slag, collectively waste sources of metal oxides, further described in U.S. Patent Application No. 12/486692, filed 17 June 2009, Publication Number US 2010-0000444 Al, published 7 January 2010, titled, "Methods And Systems For Utilizing Waste Sources Of Metal Oxides." the disclosure of which is incorporated herein in its entirety, may be used in alone or in combination with other proton-removing agents to provide proton-removing agents for the invention. Agricultural waste, either through animal waste or excessive fertilizer use, may contain potassium hydroxide (KOH) or ammonia (NH3) or both. As such, agricultural waste may be used in some embodiments of the invention as a proton-removing agent. This agricultural waste is often collected in ponds, but it may also percolate down into aquifers, where it can be accessed and used.

[00125] In some embodiments of the invention, ash may be employed for proton-removing agents, e.g., to increase the pH of C02-charged water. The ash may be used as a as the sole pH
modifier or in conjunction with one or more additional pH modifiers. Of interest in certain embodiments is use of a coal ash as the ash.

-38- Docket No. CLRA-026W0 The coal ash as employed in this invention refers to the residue produced in power plant boilers or coal burning furnaces, for example, chain grate boilers, cyclone boilers and fluidized bed boilers, from burning pulverized anthracite, lignite, bituminous or sub-bituminous coal. Such coal ash includes fly ash which is the fmely divided coal ash carried from the furnace by exhaust or flue gases; and bottom ash which collects at the base of the furnace as agglomerates.
[00126] Fly ashes are generally highly heterogeneous, and include of a mixture of glassy particles with various identifiable crystalline phases such as quartz, mullite, and various iron oxides. Fly ashes of interest include Type F and Type C fly ash. The Type F and Type C fly ashes referred to above are defined by CSA
Standard A23.5 and ASTM C618. The chief difference between these classes is the amount of calcium, silica, alumina, and iron content in the ash. The chemical properties of the fly ash are largely influenced by the chemical content of the coal burned (i.e., anthracite, bituminous, and lignite). Fly ashes of interest include substantial amounts of silica (silicon dioxide, Si02) (both amorphous and crystalline) and lime (calcium oxide, CaO, magnesium oxide, MgO).
[00127] Table 3 below provides the chemical makeup of various types of fly ash that fmd use in embodiments of the invention.

Table 3. Chemical makeup of various types of fly ash.

Component Bituminous Subbituminous Lignite Si02 (%) 20-60 40-60 15-45 A1203 (%) 5-35 20-30 20-25 Fe203 (%) 10-40 4-10 4-15 CaO (%) 1-12 5-30 15-40 [00128] The burning of harder, older anthracite and bituminous coal typically produces Class F fly ash. Class F fly ash is pozzolanic in nature, and contains less than 10 ia lime (CaO).
Fly ash produced from the burning of younger lignite or subbituminous coal, in addition to having pozzolanic properties, also has some self-cementing properties. In the presence of water, Class C fly ash will harden and gain strength over time. Class C fly ash generally contains more than 20% lime (CaO). Alkali and sulfate (SO4) contents are generally higher in Class C fly ashes.
[00129] Fly ash material solidifies while suspended in exhaust gases and is collected using various approaches, e.g., by electrostatic precipitators or filter bags. Since the particles solidify while suspended in the exhaust gases, fly ash particles are generally spherical in shape and range in size from 0.5 m to 100 m. Fly ashes of interest include those in which at least 80%, bv weight comprises particles of less than 45 microns.
Also of interest in certain embodiments of the invention is the use of highly alkaline fluidized bed combustor (FBC) fly ash.

-39- Docket No. CLRA-026W0 [00130] Also of interest in embodiments of the invention is the use of bottom ash. Bottom ash is formed as agglomerates in coal combustion boilers from the combustion of coal. Such combustion boilers may be wet bottom boilers or dry bottom boilers. When produced in a wet or dry bottom boiler, the bottom ash is quenched in water. The quenching results in agglomerates having a size in which 90% fall within the particle size range of 0.1 mm to 20 mm, where the bottom ash agglomerates have a wide distribution of agglomerate size within this range. The main chemical components of a bottom ash are silica and alumina with lesser amounts of oxides of Fe, Ca, Mg, Mn, Na and K, as well as sulfur and carbon.
[00131] Also of interest in certain embodiments is the use of volcanic ash as the ash. Volcanic ash is made up of small tephra, i.e., bits of pulverized rock and glass created by volcanic eruptions, less than 2 millimeters (0.079 in) in diameter.
[00132] In one embodiment of the invention, cement kiln dust (CKD) is added to the reaction vessel as a means of modifying pH. The nature of the fuel from which the ash and/or CKD
were produced, and the means of combustion of said fuel, will influence the chemical composition of the resultant ash and/or CKD. Thus ash and/or CKD may be used as a portion of the means for adjusting pH, or the sole means, and a variety of other components may be utilized with specific ashes and/or CKDs, based on chemical composition of the ash and/or CKD.
[00133] In embodiments of the invention, ash is added to the reaction as one source of these additional reactants, to produce carbonate mineral precipitates which contain one or more components such as amorphous silica, crystalline silica, calcium silicates, calcium alumina silicates, or any other moiety which may result from the reaction of ash in the carbonate mineral precipitation process.
[00134] The ash employed in the invention may be contacted with the water to achieve the desired pH
modification using any convenient protocol, e.g., by placing an amount of ash into the reactor holding the water, where the amount of ash added is sufficient to raise the pH to the desired level, by flowing the water through an amount of the ash, e.g., in the form of a column or bed, etc.
[00135] In certain embodiments where the pH is not raised to a level of 12 or higher, the fly ash employed in the method, e.g., as described below, may not dissolve but instead will remain as a particulate composition.
This un-dissolved ash may be separated from the remainder of the reaction product, e.g., filtered out, for a subsequent use. Alternatively, the water may be flowed through an amount of ash that is provided in an immobilized configuration, e.g., in a column or analogous structure, which provides for flow through of a liquid through the ash but does not allow ash solid to flow out of the structure with the liquid. This embodiment does not require separation of un-dissolved ash from the product liquid. In yet other embodiments where the pH exceeds 12, the ash dissolved and provides for pozzolanic products, e.g., as described in greater detail elsewhere.

[00136] In embodiments of the invention where ash is utilized in the precipitation process, the ash may first be removed from the flue gas by means such as electrostatic precipitation, or may be utilized directly via the flue -40- Docket No. CLRA-026W0 gas. The use of ash in embodiments of the invention may provide reactants such as alumina or silica in addition to raising the pH.
[00137] In certain embodiments of the invention, slag is employed as a pH
modifying agent, e.g., to increase the pH of the CO2 charged water. The slag may be used as a as the sole pH
modifier or in conjunction with one or more additional pH modifiers, e.g., ashes, etc. Slag is generated from the processing of metals, and may contain calcium and magnesium oxides as well as iron, silicon, and aluminum compounds. In certain embodiments, the use of slag as a pH modifying material provides additional benefits via the introduction of reactive silicon and alumina to the precipitated product. Slags of interest include, but are not limited to, blast furnace slag from iron smelting, slag from electric-arc or blast furnace processing of steel, copper slag, nickel slag and phosphorus slag.
[001381 Electrochemical methods provide another means to remove protons from various species in a solution, either by removing protons from solute (e.g., deprotonation of carbonic acid or bicarbonate) or from solvent (e.g., deprotonation of hydronium or water). Deprotonation of solvent may result, for example, if proton production from CO2 dissolution matches or exceeds electrochemical proton removal from solute molecules. In some embodiments, low-voltage electrochemical methods are used to remove protons, for example, as CO2 is dissolved in the precipitation reaction mixture or a precursor solution to the precipitation reaction mixture (i.e., a solution that may or may not contain divalent cations). In some embodiments, CO2 dissolved in an aqueous solution that does not contain divalent cations is treated by a low-voltage electrochemical method to remove protons from carbonic acid, bicarbonate, hydronium, or any species or combination thereof resulting from the dissolution Of COZ. A low-voltage electrochemical method operates at an average voltage of 2, 1.9, 1.8, 1.7, or 1.6 V or less, such as 1.5, 1.4, 1.3, 1.2, 1.1 V or less, such as 1 V or less, such as 0.9 V or less, 0.8 V or less, 0.7 V or less, 0.6 V or less, 0.5 V or less, 0.4 V or less, 0.3 V or less, 0.2 V or less, or 0.1 V or less. Low-voltage electrochemical methods that do not generate chlorine gas are convenient for use in systems and methods of the invention. Low-voltage electrochemical methods to remove protons that do not generate oxygen gas are also convenient for use in systems and methods of the invention.
In some embodiments, low-voltage methods do not generate any gas at the anode.
In some embodiments, low-voltage electrochemical methods generate hydrogen gas at the cathode and transport it to the anode where the hydrogen gas is converted to protons. Electrochem.ical methods that do not generate hydrogen gas may also be convenient. In some instances, electrochemical methods to remove protons do not generate any gaseous by-byproduct. Electrochemical methods for effecting proton removal are further described in U.S.
Patent Application No. 12/344.019, filed 24 December 2008; U.S. Patent Application No. 12/375,632, filed 23 December 2008; International Patent Application No. PCT/US08/088242, filed 23 December 2008;
International Patent Application No. PCT/US09/32301, filed 28 January 2009;
and International Patent Application No. PCT/US09/48511, filed 24 June 2009, each of which are incorporated herein by reference in their entirety.

-41- Docket No. CLRA-026W0 [00139] Alternatively, electrochemical methods may be used to produce caustic molecules (e.g., hydroxide) through, for example, the chlor-alkali process, or modification thereof (e.g., low-voltage modification).
Electrodes (i.e., cathodes and anodes) may be present in the apparatus containing the aqueous solution or waste gas-charged (e.g., C02-charged) solution, and a selective barrier, such as a membrane, may separate the electrodes. Electrochemical systems and methods for removing protons may produce by-products (e.g., hydrogen) that may be harvested and used for other purposes. Additional electrochemical approaches that may be used in systems and methods of the invention include, but are not limited to, those described in U.S.
Provisional Patent Application No. 61/081,299, filed 16 July 2008, and U.S.
Provisional Patent Application No. 61/091,729, the disclosures of which are incorporated herein by reference.
Combinations of the above mentioned sources of proton-removing agents and methods for effecting proton removal may be employed.
[00140] In embodiments in which an electrochemical process is used to remove protons and/or to produce base, often an acid stream, such as an HC1 stream, is also generated, and this stream, alone or any other convenient source of acid, or a combination thereof, may be used to enhance dissolution of, e.g., magnesium-bearing minerals such as olivine or serpentine, or sources of calcium such as cement waste. Dissolution may be further enhanced by sonication methods, which can produce localized pockets of extreme temperature and pressure, enhancing reaction rates by one hundred to over one million-fold.
Such methods are known in the art.
[00141] In some embodiments the methods of the invention allow large amounts of magnesium and, in some cases, calcium, to be added to the water used in some embodiments of the invention, increasing the amount of precipitate that may be formed per unit of water in a single precipitation step, allowing surprisingly high yields of carbonate-containing precipitate when combined with methods of dissolution of CO2 from an industrial source in water, e.g., seawater or other saltwater source. In some embodiments, the methods of the invention include a method of removing COz from a gaseous source, e.g., an industrial gaseous source of CO2 such as flue gas from a power plant, or such as exhaust gas from a cement plant, by performing a precipitation step on water into which CO2 has been. dissolved from the gaseous source of CO2, where the precipitation step provides precipitate in an amount of 10 g/L or more in a single precipitation step, 15 g/L or more in a single precipitation step, 20 g/L or more in a single precipitation step, 25 g/L or more in a single precipitation step, 30 g/L or more in a single precipitation step, 40 g/L or more in a single precipitation step, 50 g/L or more in a single precipitation step, 60 g/L or more in a single precipitation step, 70 g/L or more in a single precipitation step, 80 g/L or more in a single precipitation step, 90 g/L or more in a single precipitation step, 100 g/L or more in a single precipitation step, 125 g/L or more in a single precipitation step, or 150 g/L or more in a single precipitation step.
[00142] In some embodiments, the methods of the invention include a method of removing CO2 from a gaseous source, e.g., an industrial gaseous source of CO2 such as flue gas from a power plant, or such as exhaust gas from a cement plant, by subjecting a water (e.g. a sea water, a brine, an absorbing solution) into which CO2 has been dissolved from the gaseous source of CO2 (e.g. an industrial source of carbon dioxide) to -42- Docket No. CLRA-026W0 precipitation conditions, where the precipitation conditions provide precipitate in an amount of 136 ton/hour to 445 ton/hour averaged over a period of 72 hours of continuous application of the precipitation conditions.
[00143] In some embodiments, the methods of the invention include a method of removing CO2 from a gaseous source, e.g., an industrial gaseous source of CO2 such as flue gas from a power plant, or such as exhaust gas from a cement plant, by subjecting a water (e.g. a sea water, a brine, an absorbing solution) into which CO2 has been dissolved from the gaseous source of CO2 (e.g. an industrial source of carbon dioxide) to precipitation conditions, where the precipitation conditions provide precipitate in an amount of 2.6 grams of precipitate per liter of absorbing solution to 26.11 grams of precipitate per liter of absorbing solution averaged over a period of 72 hours of continuous application of the precipitation conditions. In some embodiments, the precipitation conditions provide precipitate in an amount of 5.2 grams of precipitate per liter of absorbing solution to 26.11 grams of precipitate per liter of absorbing solution averaged over a period of 72 hours of continuous application of the precipitation conditions. In some embodiments, the precipitation conditions provide precipitate in an amount of 7.83 grams of precipitate per liter of absorbing solution to 26.11 grams of precipitate per liter of absorbing solution averaged over a period of 72 hours of continuous application of the precipitation conditions, such as 9.14 to 26.11, such as 10.44 to 26.11, such as 11.75 to 26.11, such as 13.05 to 26.11, such as 14.36 to 26.11, such as 15.66 to 26.11, such as 16.97 to 26.11, such as 18.27 to 26.11, such as 19.58 to 26.11, such as 20.88 to 26.11, such as 22.19 to 26.11, such as 23.5 to 26.11, such as 24.8 to 26.11 grams of precipitate per liter of absorbing solution.
[00144] In some embodiments, the precipitate comprises magnesium carbonate; in some embodiments the precipitate comprises calcium carbonate; in some embodiments, the precipitate comprises magnesium and calcium, and/or magnesium/calcium carbonates. In some embodiments the ratio of magnesium to calcium in the precipitated material produced in a single precipitation step is at least 0.5:1, or at least 1:1, or at least 2:1, or at least 3:1, or at least 4:1, or at least 5:1, or at least 6:1, or at least 7:1, or at least 8:1, or at least 9:1, or at least 10:1. In some embodiments the ratio of magnesium to calcium in the precipitated material produced in a single precipitation step is at least 2:1. In some embodiments the ratio of magnesium to calcium in the precipitated material produced in a single precipitation step is at least 4:
l. . In some embodiments the ratio of magnesium to calcium in the precipitated material produced in a single precipitation step is at least 6:1. In some embodiments, the precipitate contains calcium and magnesium carbonates, and contains components that allow at least a portion of the carbon in the carbonate to be traced back to a fossil fuel origin.
[00145] In some embodiments, the precipitate comprises magnesium carbonate; in some embodiments the precipitate comprises calcium carbonate; in some embodiments, the precipitate comprises magnesium and calcium, and/or magnesium/calcium carbonates. In some embodiments the ratio of magnesium to calcium in the precipitated material produced averaged over 72 hours of application of precipitation conditions is at least 0.5:1, or at least 1:1, or at least 2:1, or at least 3:1, or at least 4:1, or at least 5:1, or at least 6:1, or at least 7:1, or at least 8:1, or at least 9:1, or at least 10:1. In some embodiments the ratio of magnesium to calcium in the precipitated material produced in averaged. over 72 hours of application of precipitation conditions is at least -43- Docket No. CLRA-026W0 2:1. In some embodiments the ratio of magnesium to calcium in the precipitated material produced averaged over 72 hours of application of precipitation conditions is at least 4:1. In some embodiments the ratio of magnesium to calcium in the precipitated material produced averaged over 72 hours of application of precipitation conditions is at least 6:1. In some embodiments, the precipitate contains calcium and magnesium carbonates, and contains components that allow at least a portion of the carbon in the carbonate to be traced back to a fossil fuel origin.
[00146] As reviewed above, methods of the invention include subjecting water (which may or may have been charged in a charging reactor with C02, as described above) to precipitation conditions sufficient to produce a storage-stable precipitated carbon dioxide sequestering product. Any convenient precipitation conditions may be employed, which conditions result in the production. of the desired sequestering product.
[00147] Precipitation conditions of interest include those that modulate the physical environment of the water to produce the desired precipitate product. For example, the temperature of the water may be adjusted to a level suitable for precipitation of the desired product to occur. In such embodiments, the temperature of the water may be adjusted to a value from 0 C to 90 C, such as from 20 C to 50 C and including from 25 C to 45 C. As such, while a given set of precipitation conditions may have a temperature ranging from 0 C to 100 C, the temperature may be adjusted in certain embodiments to produce the desired precipitate. The temperature of the water may be adjusted using any convenient protocol. In some instances, the temperature is adjusted using energy generated from low or zero carbon dioxide emission sources, e.g., solar energy sources, wind energy sources, hydroelectric energy sources, geothermal energy sources, from the waste heat of the flue gas which can range up to 500 C when heating is needed, etc.
[00148] While the pH of the water may range from 7 to 14 during a given precipitation process, in some instances the pH is raised to alkaline levels in order to produce the desired precipitation product. In these embodiments, the pH is raised to a level sufficient to cause precipitation of the desired C02-sequestering product, as described above. As such, the pH may be raised to 9.5 or higher, such as 10 or higher, including 10.5 or higher. Where desired, the pH may be raised to a level that minimizes if not eliminates CO2 production during precipitation. For example, the pH may be raised to a value of 10 or higher, such as a value of 11 or higher. In certain embodiments, the pH is raised to between 7 and 11, such as between 8 and 11, including between 9 and 11, for example between 10 and 11. In this step, the pH may be raised to and maintained at the desired alkaline level, such that the pH is maintained at a constant alkaline level, or the pH
may be transitioned or cycled between two or more different alkaline levels, as desired.
[00149] In normal seawater, 93% of the dissolved CO2 is in the form of bicarbonate ions (HCO3') and 6% is in the form of carbonate ions (C03z-). When calcium carbonate precipitates from normal seawater, CO2 is released. In fresh water, above pH 10.33, greater than 90% of the carbonate is in the form of carbonate ion, and no CO2 is released during the precipitation of calcium carbonate. In seawater this transition occurs at a slightly lower pH, closer to a pH of 9.7. While the pH of the water employed in methods may range from 5 to 14 during a given precipitation process, in certain embodiments the pH is raised to alkaline levels in order to -44- Docket No. CLRA-026W0 drive the precipitation of carbonate compounds, as well as other compounds, e.g., hydroxide compounds, as desired. In certain of these embodiments, the pH is raised to a level which minimizes if not eliminates CO2 production during precipitation, causing dissolved CO2, e.g., in the form of carbonate and bicarbonate, to be trapped in the carbonate compound precipitate. In these embodiments, the pH
may be raised to 9 or higher, such as 10 or higher, including 11 or higher.
[00150] As summarized above, the pH of the water source, e.g., alkaline earth metal ion-containing water, is raised using any convenient approach. In certain embodiments, a pH raising agent may be employed, where examples of such agents include oxides (calcium oxide, magnesium oxide), hydroxides (e.g., potassium hydroxide, sodium hydroxide, brucite (Mg(OH)2, etc.), carbonates (e.g., sodium carbonate) and the like.
[00151] As indicated above, ash (or slag in certain embodiments) is employed in certain embodiments as the sole way to modify the pH of the water to the desired level. In yet other embodiments, one or more additional pH modifying protocols is employed in conjunction with the use of ash.
[00152] Alternatively or in conjunction with the use of a pH-elevating agent (such as described above), the pH
of the water (e.g., alkaline earth metal ion-containing water) source can be raised to the desired level by electrolysis of the water using an electrolytic or electrochemical protocol.
Electrochemical protocols of interest include, but are not limited to, those described. above as well as those described in U.S. Provisional Patent Application No. 61/081,299, filed 16 July 2008 and U.S. Provisional Patent Application No.
61/091,729, filed 25 August 2008, each of which is incorporated herein by reference in its entirety. Also of interest are the electrolytic approaches described in U.S. Patent Application Publication No. 2006/0185985, published 24 August 2006 and U.S. Patent Application Publication No.
2008/0248350, published 9 October 2008, as well as International Patent Application Publication No. WO
2008/018928, published 14 February 2008, each of which is incorporated herein by reference in its entirety.
[00153] Where desired, additives other than pH elevating agents may also be introduced into the water in order to influence the nature of the precipitate that is produced. As such, certain embodiments of the methods include providing an additive in the water before or during the time when the water is subjected to the precipitation conditions. Certain calcium carbonate polymorphs can be favored by trace amounts of certain additives. For example, vaterite, a highly unstable polymorph of CaCO3 that precipitates in a variety of different morphologies and converts rapidly to calcite, can be obtained at very high yields by including trace amounts of lanthanum as lanthanum chloride in a supersaturated solution of calcium carbonate. Other additives besides lanthanum that are- of interest include, but are not limited to transition metals and the like.
For instance, the addition of ferrous or ferric iron is known to favor the formation of disordered doloniite (protodolomite) where it would not form otherwise.
[00154] The nature of the precipitate can also be int7uenced by selection of appropriate major ion ratios.
Major ion ratios also have considerable influence of polymorph forma.tion. For example, as the magnesium:calcium ratio in the water increases, araQonite becomes the favored polymorph of calcium -45- Docket No. CLRA-026W0 carbonate over low-magnesium calcite. At low magnesium:calcium ratios, low-magnesium calcite is the preferred polymorph.
[00155] Rate of precipitation also has a large effect on compound phase formation. The most rapid precipitation can be achieved by seeding the solution with a desired phase.
Without seeding, rapid precipitation can be achieved by rapidly increasing the pll of the sea water, which results in more amorphous constituents. When silica is present, the more rapid the reaction rate, the more silica is incorporated with the carbonate precipitate. The higher the pH is, the more rapid the precipitation is, and the more amorphous the precipitate is.
[00156] Accordingly, a set of precipitation conditions to produce a desired precipitate from a water include, in certain embodiments, the water's temperature and pH, and in some instances the concentrations of additives and ionic species in the water. Precipitation conditions may also include factors such as mixing rate, forms of agitation such as ultrasonics, and the presence of seed crystals, catalysts, membranes, or substrates. In some embodiments, precipitation conditions include supersaturated conditions, temperature, pH, and/or concentration gradients, or cycling or changing any of these parameters. The protocols employed to prepare carbonate compound precipitates according to the invention may be batch or continuous protocols. It will be appreciated that precipitation conditions may be different to produce a given precipitate in a continuous flow system compared to a batch system.
[00157] In certain embodiments, contact between the water (e.g., alkaline earth metal ion-containing water) and CO2 may be accomplished using any convenient protocol, (e.g., spray gun, segmented flow-tube reactor) to control the range of sizes of precipitate particles. One or more additives may be added to the metal-ion containing water source, e.g., flocculants, dispersants, surfactants, antiscalants, crystal growth retarders, sequestration agents etc, in the methods and systems of the claimed invention in order to control the range of sizes of precipitate particles.
[00158] The pH of the water may be raised using any convenient approach.
Approaches of interest as described in greater detail herein include, but are not limited to: use of a pH raising agent, electrochemical approaches, using naturally alkaline water such as from an alkaline lake, etc.
In some instances, a pH-raising agent may be employed, where examples of such agents include oxides (such as calcium oxide, magnesium oxide, etc.), hydroxides (such as sodium hydroxide, potassium hydroxide, and magnesium hydroxide), carbonates (such as sodium carbonate), and the like. The amount of pH
elevating agent which is added to the water will depend on the particular nature of the agent and the volume of water being modified, and will be sufficient to raise the pH of the water to the desired value.
[00159] Described below are electrochernical processes and systems that may be used in embodiments of the invention. The processes and systems make use of one or more ion-selective membranes (a low-voltage system for producing hydroxide). These processes and systems are fiirther described in International Patent Application No. PCT/US08/88242, filed 23 December 2008, titled "Low-Energy Electrochemical Hydroxide System and Method," and International Patent Application No. PCT/tJS08/88246, filed 23 December 2008, -46- Docket No. CLRA-026W0 titled "Low-Energy Electrochemical Proton Transfer System and Method," each of which is incorporated herein by reference in its entirety.

Low voltage system for production of hydroxide [00160] A second set of methods and systems for removing protons from aqueous solution/producing hydroxide pertains to a low energy process for electrochemically preparing an ionic solution utilizing an ion exchange membrane in an electrochemical cell. In one embodiment, the system comprises an electrochemical system wherein an ion exchange membrane separates a first electrolyte from a second electrolyte, the first electrolyte contacting an anode and the second electrolyte contacting a cathode. In the system, on applying a voltage across the anode and cathode, hydroxide ions form at the cathode and a gas does not form at the anode.
[00161] In an another embodiment, the system comprises an electrochemical system comprising a first electrolytic cell including an anode contacting a first electrolyte, and an anion exchange membrane separating the first electrolyte from a third electrolyte; and a second electrolytic cell including a second electrolyte contacting a cathode and a cation exchange membrane separating the first electrolyte from the third electrolyte; wherein on applying a voltage across the anode and cathode, hydroxide ions form at the cathode and a gas does not form at the anode.
[00162] In one embodiment the method comprises placing an ion exchange membrane between a first electrolyte and a second electrolyte, the first electrolyte contacting an anode and the second electrolyte contacting a cathode; and migrating ions across the ion exchange membrane by applying a voltage across the anode and cathode to form hydroxide ions at the cathode without forming a gas at the anode.
[00163] In another embodiment the method comprises placing a third electrolyte between an anion exchange membrane and a cation exchange membrane; a first electrolyte between the anion exchange and an anode; and second electrolyte between the cation exchange membrane and a cathode; and migrating ions across the cation exchange membrane and the anion exchange membrane by applying a voltage to the anode and cathode to form hydroxide ions at the cathode without forming a gas at the anode.
[00164] By the methods and systems, ionic species from one solution are transferred to another solution in a low voltage electrochemical manner, thereby providing anionic solutions for various applications, including preparing a solution of sodium hvdroxide for use in sequestration carbon dioxide as described herein. In one embodiment, a solution comprising OH- is obtained from salt water and used in sequestering COZ by precipitating calcium and magnesium carbonates and bicarbonates from a salt solution comprising alkaline earth metal ions as described herein.
[00165] The methods and systems in various embodiments are directed to a low voltage electrochemical system and method for generating a solution of sodium hydroxide in an aqueous solution utilizing one or more ion exchange membranes wherein, a gas is not formed at the anode and wherein hydroxyl ions are formed at the cathode. Thus, in some embodiments, hydroxide ions arc formed in an electrochemical process -47- Docket No. CLRA-026W0 without the formation of oxygen or chlorine gas. In some embodiments, hydroxide ions are formed in an electrochemical process where the voltage applied across the anode and cathode is less than 2.8 V, 2.7 V, 2.5 V, 2.4 V, 2.3 V, 2.2 V, 2.1 V, 2.0 V, 1.9 V, 1.8 V, 1.7 V, 1.6 V, 1.5 V, 1.4 V, 1.3 V, 1.2 V, 1.1 V, 1.0 V, 0.9 V, 0.8 V, 0.7 V, 0.6 V, 0.5 V, 0.4 V, 0.3 V, 0.2 V, or 0.1 V. In various embodiments, an ionic membrane is utilized to separate a salt water in contact with the anode, from a solution of e.g., sodium chloride in contact with the cathode. On applying a low voltage across the cathode and anode, a solution of e.g., sodium hydroxide is formed in the solution around the cathode; concurrently, an acidified solution comprising hydrochloric acid is formed in the solution around the anode. In various embodiments, a gas such as chorine or oxygen does not form at the anode.
[00166] In various embodiments, the sodiuin hydroxide sohition is useable to sequester CO2 as described herein, and the acidic solution is useable to dissolve calcium and magnesium bearing minerals to provide a calcium and magnesium ions for sequestering C02, also as described herein.
[00167] Turning to Figs. 8-10, in various embodiments the system is adaptable for batch and continuous processes as described herein. Referring to Figs. 8-9, in one embodiment the system includes an electrochemical cell wherein an ion exchange membrane (802, 824) is positioned to separate a first electrolyte (804) from a second electrolyte (806), the first electrolyte contacting an anode (808) and the second electrolyte contacting a cathode (810). As illustrated in Fig. 8, an anion exchange membrane (802) is utilized;
in Fig. 9, a cation exchange membrane (824) is utilized.
[00168] In various embodiments as illustrated in Figs. 8 and 9, first electrolyte (804) comprises an aqueous salt solution comprising seawater, freshwater, brine, or brackish water or the like; and second electrolyte comprises a solution substantially of sodium chloride. In various embodiments, second (806) electrolyte may comprise seawater or a concentrated solution of sodium chloride. In various embodiments anion exchange membrane (802) and cation exchange membrane (824) comprise a conventional ion exchange membranes suitable for use in an acidic and/or basic solution at operating temperatures in an aqueous solution up to 100 C. As illustrated in Figs. 8 and 9, first and second electrolytes are in contact with the anode and cathode to complete an electrical circuit that includes voltage or current regulator (812). The current/voltage regulator is adaptable to increase or decrease the cu.rrent or voltage across the cathode and anode in the system as desired.
[00169] With reference to Figs. 8 and 9, in various embodiments, the electrochemical cell includes first electrolyte inlet port (814) adaptable for inputting first electrolyte (804) into the system and in contact with anode (808). Similarly, the cell includes second electrolyte inlet port (816) for inputting second electrolyte (806) into the system and in contact with cathode (810). Additionally, the cell includes outlet port (818) for draining first electrolyte from the cell, and outlet port (820) for draining second electrolyte from the cell. As will be appreciated by one ordinarily skilled, the inlet and outlet ports are adaptable for various flow protocols including batch flow, semi-batch flow, or continuous flow. In alternative embodiments, the system includes a duct (822) for directing gas to the anode; in various embodiments the gas comprises hydrogen formed at the cathode (810).

-48- Docket No. CLRA-026W0 [00170] With reference to Fig. 8 where an anion membrane (802) is utilized, upon applying a low voltage across the cathode (810) and anode (808), hydroxide ions form at the cathode (810) and a gas does not form at the anode (808). Further, where second electrolyte (806) comprises sodium chloride, chloride ions migrate into the first electrolyte (804) from the second electrolyte (806) through the anion exchange membrane (802);
protons form at the anode (808); and hydrogen gas forms at the cathode (810).
As noted above, a gas e.g., oxygen or chlorine does not form at the anode (808).
[00171] With reference to Fig. 9 where a cation membrane (824) is utilized, upon applying a low voltage across the cathode (810) and anode (808), hydroxide ions form at the cathode (810) and a gas does not form at the anode (808). In various embodiments cation exchange membrane (824) comprises a conventional cation exchange membrane suitable for use with an acidic and basic solution at operating temperatures in an aqueous solution up to 100 C. As illustrated in Fig. 9, first and second electrolytes are in contact with the anode and cathode to complete an electrical cir;,uit that includes voltage and/or current regulator (812). The voltage/current regulator is adaptable to increase or decrease the current or voltage across the cathode and anode in the system as desired. In the system as illustrated in Fig. 9 wherein second electrolyte (806) comprises sodium chloride, sodium ions migrate into the second electrolyte (806) from the first electrolyte (804) through the cation exchange membrane (824); protons form at the anode (808); and hydrogen gas forms at the cathode (810). As noted above, a gas e.g., oxygen or chlorine does not form at the anode (808).
[00172] As can be appreciated by one ordinarily skilled in the art, and with reference to Fig. 8 in second electrolyte (806) as hydroxide ions from the anode (810) and enter in to the second electrolyte (806) concurrent with migration of chloride ions from the second electrolyte, an aqueous solution of sodium hydroxide will form in second electrolyte (806). Consequently, depending on the voltage applied across the system and the flow rate of the second electrolyte (806) through the system, the pH of the second electrolyte is adjusted. In one embodiment, when a potential of 0.1 V or less, 0.2 V or less, 0.3 V or less, 0.4 V or less, 0.5 V or less, 0.6 V or less, 0.7 V or less, 0.8 V or less, 0.9 V or less, 1.0 V or less, 1.1 V or less, 1.2 V or less, 1.3 V or less, 01.4 V or less, 1.5 V or less, 1.6 V or less, 1.7 V or less, 1.8 V or less, 1.9 V or less, or 2.0 V or less, is applied across the anode and cathode, the pH of the second electrolyte solution increased; in another embodiment, when a volt of 0.1 V to 2.0 V is applied across the anode and cathode the pH of the second electrolyte increased; in yet another embodiment, when a voltage of 0.1 V to 1 V is applied across the anode and cathode the pH of the second electrolyte solution increased. Similar results are achievable with voltages of 0.1 Vto0.8V;0.1 Vto0.7V;0.1 Vto0.6V;0.1 Vto0.5V;0.1 V to 0.4 V;
and 0.1 Vto0.3V
across the electrodes. Exemplary results achieved in accordance with the system are summarized in Table 2.
Table 2. Low energy electrochemical method and system.

Volt across Time (sec) Initial pH at End pH at Initial pH at End pH at Electrodes Anode Anode Cathode Cathode -49- Docket No. CLRA-026W0 0.6 2000 6.7 3.8 6.8 10.8 1.0 2000 6.6 3.5 6.8 11.1 [00173] In this example, both the anode and the cathode comprise platinum, and the first and second electrolytes comprise a solution of sodium chloride.
[001741 Similarly, with reference to Fig. 9, in second electrolyte (806) as hydroxide ions from the anode (810) enter into the solution concurrent with migration of sodium ions from the first electrolyte to the second electrolyte, increasingly an aqueous solution of sodium hydroxide will form in second electrolyte (806).
Depending on the voltage applied across the system and the flow rate of the second electrolyte through the system, the pH of the solution will be adjusted. In one embodiment, when a volt of 0.1 V or less, 0.2 V or less, 0.3 V or less, 0.4 V or less, 0.5 V or less, 0.6 V or less, 0.7 V or less, 0.8 V or less, 0.9 V or less, 1.0 V
or less, 1.1 V or less, 1.2 V or less, 1.3 V or less, 1.4 V or less, 1.5 V or less, 1.6 V or less, 1.7 V or less, 1.8 V or less, 1.9 V or less, or 2.0 V or less is applied across the anode and cathode, the pH of the second electrolyte solution increased; in another embodiment, when a volt of 0.1 V to 2.0 V is applied across the anode and cathode the pH of the second electrolyte increased; in yet another embodiment, when a voltage of 0.1 V to 1 V is applied across the anode and cathode the pH of the second electrolyte solution increased.
Similar results are achievable with voltages of 0.1 V to 0.8 V; 0.1 V to 0.7 V; 0.1 V to 0.6 V; 0.1 V to 0.5 V;
0.1 V to 0.4 V; and 0.1 V to 0.3 V across the electrodes. In one enibodiment, a volt of 0.6 V or less is applied across the anode and cathode; in another embodiment, a volt of 0.1 V to 0.6 V
or less is applied across the anode and cathode; in yet another embodiment, a voltage of 0.1 to 1 V or less is applied across the anode and cathode.
[00175] In various embodiments and with reference to Figs. 8-10, hydrogen gas formed at the cathode (810) is directed to the anode (808) where, without being bound to any theory, it is believed that the gas is adsorbed and/or absorbed into the anode and subsequently forms protons at the anode.
Accordingly, as can be appreciated, with the formation of protons at the anode and migration of e.g., chloride ions into the first electrolyte (804) as in Fig. 8, or migration of e.g., sodium ions from the first electrolyte as in Fig. 10, an acidic solution comprising e.g., hydrochloric acid is obtained in the first electrolyte (804).
[00176] In another embodiment as illustrated in Fig. 10, the system comprises an electrochemical cell including anode (808) contacting first electrolyte (804) and an anion exchange membrane (802) separating the first electrolyte from a third electrolyte (830); and a second electrolytic cell comprising a second electrolyte (806) contacting a cathode (880) and a cation exchange membrane (824) separating the first electrolyte from the third electrolyte, wherein on applying a voltage across the anode and cathode, hydrogen ions form at the cathode without a gas forming at the anode. As with the system of Figs. 8 and 9, the system of Fig. 10 is adaptable for batch and continuous processes.
[00177] In various embodiments as illustrated in Fig. 10, first electrolyte (804) and second electrolyte (806) comprise an aqueous salt solution comprising seawater, freshwater, brine, or brackish water or the like; and -50- Docket No. CLRA-026W0 second electrolyte comprises a solution substantially of sodium chloride. In various embodiments, first (804) and second (806) electrolytes may comprise seawater. In the embodiment illustrated in Fig. 10, the third electrolyte (830) comprises substantially sodium chloride solution.
[00178] In various embodiments anion exchange membrane (802) comprises any suitable anion exchange membrane suitable for use with an acidic and basic solution at operating temperatures in an aqueous solution up to 100 C. Similarly, cation exchange membrane (824) comprises any suitable cation exchange membrane suitable for use with an acidic and basic solution at operating temperatures in an aqueous solution up to 100 oc.

[00179] As illustrated in Fig. 10, in various embodiments first elect.rolyte (804) is in contact with the anode (808) and second electrolyte (806) is in contact with the cathode (810). The third electrolyte (830), in contact with the anion and cation exchange membrane, completes an electrical circuit that includes voltage or current regulator (812). The current/voltage regulator is adaptable to increase or decrease the current or voltage across the cathode and anode in the system as desired.
[00180] With reference to Fig. 10, in various embodiments, the electrochemical cell includes first electrolyte inlet port (814) adaptable for inputting first electrolyte 804 into the system; second electrolyte inlet port (816) for inputting second electrolyte (806) into the system; and third inlet port (826) for inputting third electrolyte into the system. Additionally, the cell includes outlet port (818) for draining first electrolyte; outlet port (820) for draining second electrolyte; and outlet port (828) for draining third electrolyte. As will be appreciated by one ordinarily skilled, the inlet and outlet ports are adaptable for various flow protocols including batch flow, semi-batch flow, or continuous flow. In alternative embodiments, the system includes a duct (822) for directing gas to the anode; in various embodiments the gas is hydrogen formed at the cathode (810).
[00181] With reference to Fig. 10, upon applying a low voltage across the cathode (810) and anode (808), hydroxide ions form at the cathode (81.0) and a gas does not form at the anode (808). Further, where third electrolyte (830) comprises sodium chloride, chloride ions migrate into the first electrolyte (804) from the third electrolyte (830) through the anion exchange membrane (802); sodium ions migrate to the second electrolyte (806) from the third electrolyte (830); protons form at the anode;
and hydrogen gas forms at the cathode. As noted previously, a gas e.g., oxygen or chlorine does not form at the anode (808).
[00182] As can be appreciated by one ordinarily skilled in the art, and with reference to Fig. 10 in second electrolyte (806) as hydroxide ions from the cathode (810) enter into the solution concurrent with migration of sodium ions from the third electrolyte, increasingly an aqueous solution of sodium hydroxide will form in second electrolyte (806). Depending on the voltage applied across the system and the flow rate of the second electrolyte through the system, the pH of the solution will be adjusted. In one embodiment, when a volt of 0.1 V or less, 0.2 V or less, 0.3 V or less, 0.4 V or less, 0.5 V or less, 0.6 V
or less, 0.7 V or less, 0.8 V or less, 0.9 V or less, 1.0 V or less, 1.1 V or 1ess, 1.2 V or less, 1.3 V or less, 01.4 V or less, 1.5 V or less, 1.6 V or less, 1.7 V or less, 1.8 V or less, 1.9 V or less, or 2.0 V or less or less is applied across the anode and cathode, the pH of the second electrolyte solution increased; in another embodiment, when a volt of 0.1 to 2.0 V is -51- Docket No. CLRA-026W0 applied across the anode and cathode the pH of the second electrolyte increased; in yet another embodiment, when a voltage of 0.1 V to 1 V is applied across the anode and cathode the pH
of the second electrolyte solution increased. Similar results are achievable with voltages of 0.1 V to 0.8 V; 0.1 V to 0.7 V; 0.1 V to 0.6 V; 0.1 V to 0.5 V; 0.1 V to 0.4 V; and 0.1 V to 0.3 V across the electrodes.
In one embodiment, a volt of 0.6 volt or less is applied across the anode and cathode; in another embodiment, a volt of 0.1 V to 0.6 V or less is applied across the anode and cathode; in yet another embodiment, a voltage of 0.1 V to 1 V or less is applied across the anode and cathode.
[00183] Similarly, with reference to Fig. 10, in first electrolyte (804) as proton form at the anode (808) and enter into the solution concurrent with migration of chloride ions from the third electrolyte to the first electrolyte, increasingly an acidic solution will form in first electrolyte (804). Depending on the voltage applied across the system and the flow rate of the second electrolyte through the system, the pH of the solution will be adjusted. In one embodiment, when a volt of 0.1 V or less, 0.2 V or less, 0.3 V or less, 0.4 V
or less, 0.5 V or less, 0.6 V or less, 0.7 V or less, 0.8 V or less, 0.9 V or less, 1.0 V or less, 1.1 V or less, 1.2 V or less, 1.3 V or less, 1.4 V or less, 1.5 V or less, 1.6 V or less, 1.7 V
or less, 1.8 V or less, 1.9 V or less, or 2.0 V or less is applied across the anode and cathode, the pH of the second electrolyte solution increased; in another embodiment, when a volt of 0.1 V to 2.0 V is applied across the anode and cathode the pH of the second electrolyte increased; in yet another embodiment, when a voltage of 0.1 V to 1 V is applied across the anode and cathode the pH of the second electrolyte solution increased. Similar results are achievable with voltages of 0. 1 Vto0.8V;0.1 Vto0.7V;0.1 V to 0.6 V; 0. 1 V to 0.5 V; 0. 1 V
to 0.4 V; and 0. 1 Vto0.3V
across the electrodes. In one embodiment, a volt of 0.6 V or less is applied across the anode and cathode; in another embodiment, a volt of 0.1 V to 0.6 V or less is applied across the anode and cathode; in yet another embodiment, a voltage of 0.1 V to 1 V or less is applied across the anode and cathode as indicated in Table 2.
[00184] As illustrated in Fig. 10, hydro7en gas formed at the cathode (810) is directed to the anode (808) where, without being bound to any theory, it is believed that hydrogen gas is adsorbed and/or absorbed into the anode and subsequently forms protons at the anode and enters the first electrolyte (804). Also, in various embodiments as illustrated in Figs. 8-10. a gas such as oxygen or chlorine does not form at the anode (808).
Accordingly, as can be appreciated, with the formation of protons at the anode and migration of chlorine into the first electrolyte, hydrochloric acid is obtained in the first electrolyte (804).
[00185] As described with reference to Figs. 8-9, as hydroxide ions from the anode (810) and enter in to the second electrolyte (806) concurrent with migration of chloride ions from the second electrolyte, an aqueous solution of sodium hydroxide will form in second electrolyte (806).
Consequently, depending on the voltage applied across the system and the flow rate of the second electrolyte (806) througli the system., the pH of the second electrolyte is adjusted. In one embodiment, when a volt of 0.1 V or less, 0.2 V or less, 0.3 V or less, 0.4 V or less, 0.5 V or less, 0.6 V or less, 0.7 V or less, 0.8 V or less, 0.9 V or less, 1.0 V or less, 1.1 V or less, 1.2 V or less, 1.3 V or less, 1.4 V or less, 1.5 V or less, 1.6 V or less, 1.7 V or less, 1.8 V or less, 1.9 V
or less, or 2.0 V or less is applied across the anode and cathode, the pH of the second electrolyte solution -51- Docket No. CLRA-026W0 increased; in another embodiment, when a volt of 0.1 V to 2.0 V is applied across the anode and cathode the pH of the second electrolyte increased; in yet another embodiment, when a voltage of 0.1 V to 1 V is applied across the anode and cathode the pH of the second electrolyte solution increased. Similar results are achievable with voltages of 0.1 V to 0.8 V; 0.1 V to 0.7 V; 0.1 V to 0.6 V;
0.1 V to 0.5 V; 0.1 V to 0.4 V; and 0.1 V to 0.3 V across the electrodes. In one embodiment, when a volt of 0.6 V
or less is applied across the anode and cathode, the pH of the second electrolyte solution increased; in another embodiment, when a volt of 0.1 V to 0.6 volt or less is applied across the anode and cathode the pH of the second electrolyte increased;
in yet another embodiment, when a voltage of 0.1 V to 1 V or less is applied across the anode and cathode the pH of the second electrolyte solution increased.
[00186] Optionally, a gas including CO2 is dissolved into the second electrolyte solution by bubbling the gas into the second electrolyte solution 806 as describe above. In an optional step the resulting second electrolyte solution is used to precipitate a carbonate and/or bicarbonate compounds such as calcium carbonate or magnesium carbonate and or their bicarbonates, as described herein. The precipitated carbonate compound can be used as cements and build material as described herein.
[00187] In another optional step, acidified first electrolyte solution 804 is utilized to dissolve a calcium and/or magnesium rich mineral, such as mafic mineral including serpentine or olivine for use as the solution for precipitating carbonates and bicarbonates as described herein. In various embodiments, the resulting solution can be used as the second electrolyte solution. Similarly, in embodiments where hydrochloric acid is produced in first electrolyte 804, the hydrochloric acid can be used in place of, or in addition to, the acidified second electrolyte solution.
[00188] Embodiments described above produce electrolyte solutions enriched in bicarbonate ions and carbonate ions, or combinations thereof as well as an acid.ified stream. The acidified stream can also find application in various chemical processes. For example, the acidified stream can be employed to dissolve calcium and/or magnesium rich minerals such as serpentine and olivine to create the electrolyte solution used in the reservoir 816 (or 832). Such an electrolyte solution can be charged with bicarbonate ions and then made sufficiently basic so as to precipitate carbonate compounds as described herein.
[00189] In some embodiments, a first electrochemical process may be used to remove protons from solution to facilitate CO2 absorption, without concomitant production of hydroxide, while a second electrochemical process may be used to produce hydroxide in order to further remove protons to shift equilibrium toward carbonate and cause precipitation of carbonates. The two processes may have different voltage requirements, e.g., the first process may require lower voltage than the second, th.us minimizing total overall voltage used in the process. For example, the first process may be a bielectrode process as described in U.S. Patent Application No. 12/344,019, filed 24 December 2008, which is incoroorated herein by reference in its entirety, operating at 1.0 V or less, or 0.9 V or less, or 0.8 V or lcss, or 0.7 V or less, or 0.6 V or less, or 0.5 V
or less, or 0.4 V or less, or 0.3 V or less, or 0.2 V or less, or 0.1 V or less, while the second process may be a low-voltage hydroxide producing process as described above, operating at 1.5 V
or less, or 1.4 V or less, or -53- Docket No. CLRA-026W0 1.3 V or less, or 1.2 V or less, or 1.1 V or less, 1.0 V or less, or 0.9 V or less, or 0.8 V or less, or 0.7 V or less, or 0.6 V or less, or 0.5 V or less, or 0.4 V or less, or 0.3 V or less, or 0.2V or less, or 0.1 V or less. For example, in some embodiments the first process is a bielectrode process operating at 0.6 V or less and the second process is a low-voltage hydroxide producing process operating at 1.2 V
or less.
[001901 Also of interest are the electrocheinical approaches described in published U.S. Patent Application Publication No. 2006/0185985, published 24 August 2006; U.S. Patent Application Publication No.
2008/0248350, published 9 October 2008; International Patent Application Publication No. WO
2008/018928, published 14 February 2008; and International Patent Application Publication No. WO
2009/086460, published 7 July 2009, each of which is incorporated herein by reference in its entirety.
1001911 Stoichiometry dictates that the production of a carbonate to be precipitated in order to sequester CO2 from a source of CO2 requires the removal of two protons from the initial carbonic acid that is formed when CO2 is dissolved in water (see equations 1-5, above). Removal of the first proton produces bicarbonate and removal of the second produces carbonate, which may be precipitated as, e.g., a carbonate of a divalent cation, such as magnesium carbonate or calcium carbonate. The removal of the two protons requires some process or combination of processes that typically require energy. For example, if the protons are removed through the addition of sodium hydroxide, the source of renewable sodium hydroxide is typically the chloralkali process, which uses an electrochemi.cal process requiring at least 2.8 V and a fixed amount of electrons per mole of sodium hydroxide. That energy requirement may be expressed in terms of a carbon footprint, i.e., amount of carbon produced to provide the energy to drive the process.
[00192] A convenient way of expressing the carbon footprint for a given process of proton removal is as a percentage of the CO2 removed from the source of CO2. That is, the energy required for the removal of the protons may be expressed in terms of CO2 emission of a conventional method of power generation to produce that energy, which may in turn be expressed as a percent of the CO2 removed from the source of COz. For convenience, and as a definition in this aspect of the invention, the "CO2 produced" in such a process will be considered the CO2 that would be produced in a conventional coal/steam power plant to provide sufficient energy to remove two protons. Data are publicly available for such power plants for the last several years that show tons of CO2 produced per total MWh of energy produced. See, e.g., the website having the address produced by combining "http://carma." with "org/api/". For purposes of definition here, a value of 1 ton CO2 per MWh will be used, which corresponds closely to typical coal-fired power plants; for example, the WA
Parish plant produced 18,200,000 MWh of energy in 2000 while producing approximately 19,500,000 tons of CO2 and at present produces 21,300.00 MWh of energy while producing 20,900,000 tons of C02, which average out very close to the definitional 1 ton CO2 per MWh that will be used herein. These numbers can then be used to calculate the COZ production necessarv to remove sufficient protons to remove CO2 from a gas stream, and compare it to the CO2 removed. For example, in a process utilizing the chloralkali process operating at 2.8 V to provide base, and used to sequester CO, from a coal/stem power plant, the amount of CO2 produced by the power plant to supply the energy to create base by the chloralkali process to remove two -54 Docket No. CLRA-026W0 protons, using the 1 ton C02/1MWh ratio, would be well above 200% of the amount of CO2 sequestered by the removal of the two protons and precipitation of the CO2 in stable form. As a further condition of the defmition of "CO2 produced" in this aspect of the invention, no theoretical or actual calculations of reduction of the energy load due to, e.g., reuse of byproducts of the process for removing the protons (e.g., in the case of the chloralkali process, use of hydrogen produced in the process in a fuel cell or by direct combustion to produce energy) are included in the total of "CO2 produced." In addition, no theoretical or actual supplementation of the power supplied by the power plant with renewable sources of energy is considered, e.g., sources of energy that produce little or no carbon dioxide, such as wind, solar, tide, hydroelectric, and the like. If the process of removing protons includes the use of a hydroxide or other base, including a naturally-occurring or stockpiled base, the amount of CO2 produced would be the amount that may be stoichiometrically calculated based on the process by which the base is produced, e.g., for industrially produced base, the standard chloralkali process or other process by which the base is produced, and for natural base, the best theoretical model for the natural production of the base.
[00193] Using this definition of "CO9 produced," in soine embodiments the invention includes forming a stable C02-containing precipitate from a hiunan-produced gaseous source of C02, wherein the formation of the precipitate utilizes a process for removing protons from an aqueous solution in which a portion or all of the CO2 of the gaseous source of CO2 is dissolved, and wherein the CO2 produced by the process of removing protons is less than 100, 90, 80, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 10, or 5% of the CO2 removed from the gaseous source of CO2 by said formation of precipitate. In some embodiments, the invention includes forming a stable C02-containing precipitate from a human-produced gaseous source of C02, wherein the formation of the precipitate utilizes aProcess for removing protons from an aqueous solution in which a portion or all of the CO2 of the gaseous source of CO2 is dissolved, and wherein the COz produced by the process of removing protons is less than 70% of the COz removed from the gaseous source of CO2 by the formation of precipitate. In some embodiments the invention includes forming a stable C02-containing precipitate from a human-produced gaseous source of C02, wherein the formation, of the precipitate utilizes a process for removing protons from an aqueous solution in which a portion or all of the CO2 of the gaseous source of CO2 is dissolved, and wherein the CO~2 produced by the process of removing protons is less than 50% of the CO2 removed from the gaseous source of COz by the formation of precipitate. In some embodiments the invention includes forming a stable C02-containing precipitate from a human-produced gaseous source of C02, wherein the formation of the precipitate utilizes a process for removing protons from an aqueous solution in which a portion or all of the CO2 of the gaseous source of CO2 is dissolved, and wherein the COz produced by the process of removing protons is less than 30%
of the CO2 removed from the gaseous source of CO2 by the formation of precipitate. In some embodiments, the process of removing protons is a process, such as an electrochemical process as described herein, that removes protons without producing a base, e.g., hydroxide. In some embodiments, the process of removing protons is a process, such as an eleetrochemical process as described herein, that removes protons by producing a base, e.g., hydroxide.

-55- Docket No. CLRA-026W0 In some embodiments, the process is a combination of a process, such as an electrochemical process as described herein, that removes protons without producing a base, e.g., hydroxide, and a process, such as an electrochemical process as described herein, that removes protons by producing a base, e.g., hydroxide. In some embodiments, the process of proton removal comprises an electrochemical process, either removes protons directly (e.g., direct removal of protons) or indirectly (e.g., production of hydroxide). In some embodiments a combination of processes, e.g., electrochemical processes is used, where a first process, e.g., electrochemical process, removes protons directly and a second process, e.g., electrochemical process, removes protons indirectly (e.g., by production of hydroxide).
[00194] In some instances, precipitation of the desired product followin,g CO2 charging (e.g., as described above) occurs without addition of a source divalent metal ions. As such, after the water is charged in a charging reactor with CO7, the water is not then contacted with a source of divalent metal ions, such as one or more divalent metal ion salts, e.g., calcium chloride, magnesium chloride, sea salts, etc.
[00195] In one embodiment of the invention, a carbonate precipitation process may be employed to selectively precipitate calcium carbonate materials from the solution in order to provide the desired ratio of magnesium to calcium, followed by additional COz charging, and in some embodiments additional Mg ion charging, and a final carbonate precipitation step. This etnbodiinent is useful in utilizing concentrated waters such as desalination brine, wherein the cation content is sufficiently high that addition of more Mg ions is difficult.
This embod.iment is also useful in solutions of any concentration where two different products are desired to be produced - a primarily calcium carbonate material, and then a magnesium carbonate dominated material.
1001961 The yield of product from a given precipitation reaction may vary depending on a number of factors, including the specific type of water employed, whether or not the water is supplemented with divalent metal ions, the particular precipitation protocol employed, etc. In some instances, the precipitate protocols employed to precipitate the product are high yield precipitation protocols. In these instances, the amount of product produced from a single precipitation reaction (by which is meant a single time that that the water is subjected to precipitation conditions, such as ir.creasing the pH to a value of 9.5 or higher, such as 10 or higher as reviewed above in greater detail) may be 5 g or more, such as 10 g or more, 15 g or more, 20 g or more, 25 g or more, 30 g or more, 35 g or more, 40 g or more, 45 g or more, 50 g or more, 60 g or more, 70 g or more, 80 g or more, 90 g or more, 100 g or more, 120 g or more, 140 g or more, 160 g or more, 180 g or more, 200 g or more of the storage-stable carbon dioxide sequestering product for every liter of water. In some instances, the amount of product produced for every liter of water ranges from 5 to 200 g, such as 10 to 100 g, including 20 to 100 g. In instances where the diva] ent metal ion content of the water is not supplemented prior to subjecting the water to precipitate conditions (for example where the water is seawater and the seawater is not supplemented with a source of divalent metal ion or ions). the yield of product niay range from 5 to 20 g product per liter of water, such as 5 to 10, e.g., 6 to 8, g product per liter of water. In other instances where the water is supplemental with a source of divalent metal ions, such as magnesium andlor calcium ions, the yield of product may be higher, 2-fold higher, 3-fold higher, 5-fold higher, 10-fold higher, 20-fold higher or more, -56- Docket No. CLRA-026W0 such that the yield of such processes may range in some embodiments from 10 to 200, such as 50 to 200 including 100 to 200 g product for every liter of water subjected to precipitation conditions.
[00197] The yield of product from a given precipitation reaction may vary depending on a number of factors, including the specific type of water employed, whether or not the water is supplemented with divalent metal ions, the particular precipitation protocol employed, etc. In some instances, the precipitate protocols employed to precipitate the product are high yield precipitation protocols. In these instances, the amount of product produced from per liter of water (i.e. absorbing solution) averaged over 72 hours of continuous operation (i.e.
application of the precipitation conditions to the water or absorbing solution) may be 5 g or more, such as 10 g or more, 15 g or more, 20 g or more, 25 g or more, 30 g or more, 35 g or more, 40 g or more, 45 g or more, 50 g or more, 60 g or more, 70 g or ntore, 80 g or more, 90 g or more, 100 g or more, 120 g or more, 140 g or more, 160 g or more, 180 g or more, 200 g or more of the storage-stable carbon dioxide sequestering product for every liter of water. In some instances, the amount of product produced for every liter of water ranges from 5 to 200 g, such as 10 to 100 g, including 20 to 100 g avera.ged 72 hours of continuous operation. In instances where the divalent metal ion content of the water is not supplemented prior to subjecting the water to precipitate conditions (for example where the water is seawater and the seawater is not supplemented with a source of divalent metal ion or ions), the yield of product may range from 5 to 20 g product per liter of water, such as 5 to 10, e.g., 6 to 8, g product per liter of water as averaged over 72 hours of continuous operation. In other instances where the water is supplemental with a source of divalent metal ions, such as magnesium and/or calcium ions, the yield of product may be higher, 2-fold higher, 3-fold higher, 5-fold higher, 10-fold higher, 20-fold higher or more, such that the yield of such processes may range in some embodiments from 10 to 200, such as 50 to 200 including 100 to 200 g product for every liter of water subjected to precipitation conditions averaged over 72 hours of continuous operation.
[00198] In certain embodiments, a multi-step process is employed. In these embodiments, a carbonate precipitation process may be employed to selectively precipitate calcium carbonate materials from the solution, followed by additional steps of COZ charging and subsequent carbonate precipitation. The steps of additional CO2 charging and carbonate precipitation can in some cases be repeated one, two, three, four, five, six, seven, eight, nine, ten, or more times, precipitating additional amounts of carbonate material with each cycle. In some cases, the final pH ranges from pH 8 to pH 10, such as from pH
9 to pH 10, including from pH 9.5 to pH 10, for example, from pH 9.6 to pH 9.8.
1001991 In certain embodiments, two or more reactors may be used to carry out the methods described herein.
In these embodiments, the method may include a first reactor and a second reactor. In these cases, the first reactor is used for contacting the initial water with a magnesium. ion source and for charging the initial water with C02, as described above. The water may be agitated to facilitate the dissolution of the magnesium ion source and to facilitate contact of the initial water with the CO7. In some cases, before the CO2 charged water is transferred to the second reactor, agitation of the COz charged water is stopped, such that undissolved solids may settle by gravity. The CO, charged water is then transferred from the first reactor to the second reactor.

-57- Docket No. CLRA-026W0 After transferring the CO2 charged water to the second reactor, the step of carbonate precipitation may be performed, as described herein.
[00200] In certain embodiments, a multi-step process, as described above, employing two or more reactors, as described above, can be used to carry out the methods described herein. In these embodiments, a first reactor is used for contacting the initial water with a magnesium ion source and for charging the initial water with C02, as described above. Subsequently, the COZ charged water is transferred from the first reactor to a second reactor for the carbonate precipitation reaction. In certain enibodiments, one or more additional steps of CO2 charging and subsequent carbonate precipitation may be performed in the second reactor, as described above.
[00201] In certain embodiments, precipitation conditions can be used that favor the formation of particular morphologies of carbonate compound precipitates. For instance, precinitation conditions can be used that favor the formation of amorphous carbonate compound precipitates over the formation of crystalline carbonate compound precipitates. In these cases, in addition to contacting the initial water with a magnesium ion source and charging the initial water with C02, as described above, a precipitation facilitator may be added. In these cases, the precipitation facilitator facilitates the formation of carbonate compound precipitates at lower pH's sufficient for nucleation, but insufficient for crystal formation and growth. Examples of precipitation facilitators include, but are not limited to, aluminum sulfate (A12SO4)3. In certain embodiments, the amount of precipitation facilitator added ranges from 1 ppm to 1000 ppm, such as from 1 ppm to 500, including from 10 ppm to 200 ppm, for example from 25 ppm to 75 ppm.
Additionally, the pH of the water can be maintained between 6 and 8, such as between 7 and 8, during carbonate compound precipitation formation by alternating CO2 charging and subsequent carbonate precipitation, as described above.
[00202] Alternatively, in yet other embodiments, precipitation conditions can be used that favor the formation of crystalline carbonate compound precipitates over the formation of amorphous carbonate compound precipitates.
[00203] Further details regarding specific precipitation protocols employed in certain embodiments of the invention are provided below with respect to the description of the figures of the application.
[00204] Following production of the precipitate product from the water, a composition is produced which includes precipitated product and a mother liquor (i.e., the remaining licluid from which the precipitated product was produced). This composi_tion may be a slurry of the precipitate and mother liquor.
[00205] As summarized above, in sequestering carbon dioxide, the precipitated product is disposed of in some manner following its production. The phrase "disposed of' means that the product is either placed at a storage site or employed for a further use in another product, i.e., a manufactured or man-made item, where it is stored in that other product at least for the expected lifetime of that other product. In some instances, this disposal step includes forwarding the slurry composition described above to a long-term storage site. The storage site could be an above ground site, a below ground site or an underwater site. In these embodiments, -J$ Docket No. CLRA-026W0 following placement of the slurry at the storage site, the supernatant component of the slurry may naturally separate from the precipitate, e.g., via evaporation, dispersal, etc.
[00206] Where desired, the resulting precipitated product may be separated from the supematant component of the sluny. Separation of the precipitated product may be achieved using any of a number of convenient approaches. As detailed further herein, liquid-solid separators such as Epuramat's Extrem-Separator ("ExSep") liquid-solid separator, Xerox PARC's spiral concentrator, or a modification of either of Epuramat's ExSep or Xerox PARC's spiral concentrator, are useful in some embodiments.
Separation may also be achieved by drying the precipitated product to produce a dried precipitated product. Drying protocols of interest include filtering the precipitate from the mother liquor to produce a filtrate and then air-drying the filtrate. Where the filtrate is air dried, air-drying may be at a temperature ranging from -70 to 120 C, as desired. In some instances, drying may include placing the slurry at a drying site, such as a tailings pond, and allowing the liquid component of the precipitate to evaporate and leave behind the desired dried product. Also of interest are freeze-drying (i.e., lyophilization) protocols, where the precipitate is frozen, the surrounding pressure is reduced and enough heat is added to allow the frozen water in the material to sublime directly from the frozen precipitate phase to gas. Yet another drying protocol of interest is spray drying, where the liquid containing the precipitate is dried by feeding it through a hot gas, e.g., where the liquid feed is pumped through an atomizer into a main drying chamber and a hot gas is passed as a co-cL.rrent or counter-current to the atomizer direction.
[00207] Where the precipitated product is separated from the mother liquor, the resultant precipitate may be disposed of in a variety of different ways, as further elaborated below. For example, the precipitate may be employed as a component of a building material, as reviewed in greater detail below. Alternatively, the precipitate may be placed at a long-term storage site (sometimes referred to in the art as a carbon bank), where the site may be above ground site, a below ground site or an underwater site. Further details regarding disposal protocols of interest are provided below.
[00208] The resultant mother liquor may also be processed as desired. For example, the mother liquor may be returned to the source of the water, e.g., ocean, or to another location. In certain embodiments, the mother liquor may be contacted with a source of C02, e.g., as describec'. above, to sequester further CO2,. For example, where the mother liquor is to be returned to the ocean, the mother liquor may be contacted with a gaseous source of CO2 in a manner sufficient to increase the concentration of carbonate ion present in the mother liquor. Contact may be conducted using any convenient protocol, such as those described above. In certain embodiments, the mother liquor has an alkaline pH, and contact with the CO2 source is carried out in a manner sufficient to reduce the pH to a range between 5 and 9, e.g., 6 and 8.5, including 7.5 to 8.2.
1002091 The methods of the invention may be carried out at land or sea, e.g., at a land location where a suitable water is present at or is transported to the location, or in the ocean or other body of alkali-earth-metal-containing water, be that body naturally occurring or manmade. In certain embodiments, a system is employed to perform the above methods, where such systems include those described below in greater detail.

-59- Docket No. CLRA-026W0 [00210] The above portion of this application provides an overview of various aspects of the methods of the invention. Certain embodiments of the invention are now reviewed further in greater detail in terms of the certain figures of the invention.
[00211] Fig. 6A provides a schematic flow diagram of a carbon dioxide sequestration process that may be implemented in a system, where the system may be manifested as a stand-alone plant or as an integrated part of another type of plant, such as a power generation plant, a cement production plant, etc. In Fig. 6A, water 10 is delivered to a precipitation reactor 20, e.g., via a pipeline or other convenient manner, and subjected to carbonate mineral precipitation conditions. The water employed in the process illustrated in Fig. 6A is one that includes, for example, one or more alkaline earth metal ions such as Ca2+
and Mg2+. In certain embodiments of the invention, the water of interest is one that includes calcium in amounts ranging from 50 ppm to 20,000 ppm, such as 200 ppm to 5000 ppm and including 400 ppm to 1000 ppm. Also of interest are waters that include magnesium in amounts ranging from 50 ppm to 40,000 ppm, such as 100 ppm to 10,000 ppm and including 500 ppm to 2500 ppm. In embodiments of the invention, the water (e.g., alkaline earth metal ion-containing water) is a saltwater. As reviewed above, saltwaters of interest include a number of different types of aqueous fluids other than fresh water, such as brackish water, sea water and brine (including man-made brines, for example geothermal plant wastewaters, desalination waste waters, etc., as well as naturally occurring brines as described herein), as well as other salines having a salinity that is greater than that of freshwater. Brine is water saturated or nearly saturated with salt and has a salinity that is 50 ppt (parts per thousand) or greater. Brackish water is water that is saltier than fresh water, but not as salty as seawater, having a salinity ranging from 0.5 to 35 ppt. Seawater is water from a sea or ocean and has a salinity ranging from 35 to 50 ppt. Freshwater is water that has a salinity of less than 5 ppt dissolved salts. Saltwaters of interest may be obtained from a naturally occurring source, such as a sea, ocean, lake, swamp, estuary, lagoon, etc., or a man-made source, as desired.
[00212] As reviewed above, waters of interest also include freshwaters. In certain embodiments, the water employed in the invention may be a mineral rich, e.g., calcium and/or magnesium rich, freshwater source. In some embodiments, freshwaters, such as calcium rich waters may be combined with magnesium silicate minerals, such as olivine or serpentine, in a solution that has become acidic due to the addition of carbon dioxide from carbonic acid, which dissolves the magnesium silicate, leading to the formation of calcium magnesium silicate carbonate compounds. In certain embodiments, the water source can be freshwater wherein metal-ions, e.g., sodium, potassium, calcium, magnesium, etc. are added. Metal-ions can be added to the freshwater source using any convenient protocol, e.g., as a solid, aqueous solution, suspension etc.
[00213] In certain embodiments, the water may be obtained from the industrial plant that is also providing the gaseous waste stream. For example, in water cooled industrial plants, such as seawater cooled industrial plants, water that has been employed by the industrial plant may then be sent to the precipitation system and employed as the water in the precipitati.on reaction. Where desired, the water may be cooled prior to entering the precipitation reactor. Such approaches may be eniployed, e.g., with once-through cooling systems. For -60- Docket No. CLRA-026W0 example, a city or agricultural water supply may be employed as a once-through cooling system for an industrial plant. The water from the industrial plant may then be employed in the precipitation protocol, where output water has a reduced hardness and greater purity. Where desired, such systems may be modified to include security measures, e.g., to detect tampering (such as addition of poisons) and coordinated with governmental agencies, e.g., Homeland Security or other agencies. Additional tampering or attack safeguards may be employed in such embodiments.
[00214] As shown in Fig. 6A, an industrial plant gaseous waste stream 30 is contacted with the water at precipitation step 20 to produce a CO2 charged water (which may occur in a charging reactor in certain embodiments). The water may be an absorbing solution, where the absorbing solution allows for incorporation of carbon di.oxi.de and/or. other components from a gas into the absorbing solution. The absorbing solution may be a salt water, (e.g. sea water and/or brine), or an alkaline solution. The absorbing solution may include solid particulates and may be described as a slurry. By CO7 charged water is meant water that has had COZ gas contacted with it, where CO2 molecules have combined with water molecules to produce, e.g., carbonic acid, bicarbonate and carbonate ion. Charging water in this step results in an increase in the "CO2 content" of the water, e.g., in the form of carbonic acid, bicarbonate and carbonate ion, and a concomitant decrease in the amount of CO2 of the waste stream that is contacted with the water. The CO2 charged water is acidic in some embodiments, having a pH of 6.0 or less, such as 4.0 or less, and including 3.0 and less. In certain embodiments, the amount of COZ of the gas that is used to charge the water decreases by 85% or more, such as 99% or more as a result of this contact step, such that the methods remove 50% or more, such as 75% or more, e.g.. 85% or more, including 99% or more of the COZ
originally present in the gaseous waste stream that is contacted with the water. Contact protocols of interest include, but are not limited to: direct contacting protocols, e.g., bubbling the gas through the volume of water, concurrent contacting means, i.e., contact between unidirectionally flowing gaseous and liquid phase streams, countercurrent means, i.e., contact between oppositely flowing gaseous and liquid phase streams, and the like.
The gaseous stream may contact the water source verticallv, horizontally, or at some other angle.
[00215] The CO2 may be contacted with the water source from one or more of the following positions: below, above, or at the surface level of the water (e.g., alkaline earth metal ion-containing water). Contact may be accomplished through the use of infusers, bubblers, fluidic Ventlxri reactor, sparger, gas filter, spray, tray, catalytic bubble coltunn reactors, draft-tube type reactors or packed column reactors, and the like, as may be convenient. Where desired, two or more different CO,. charging reactors (such as columns or other types of reactor configurations) may be employed, e.g., in series or in parallel, such as three or more, four or more, etc.
In certain embodiments, various means, e.g., mechanical stirring, electromagnetic stirring, spinners, shakers, vibrators, blowers, ultrasonication, to agitate or stir the reaction solution are used to increase the contact between CO2 and the water source.

[00216] In the embodiment depicted in Fig. 6A, the water (e.g., water comprising alkaline earth metal ions) from the water source 10 is first charged with COZ to produce COZ charged water, which CO2 is then -61- Docket No. CLRA-026W0 subjected to carbonate mineral precipitation conditions. As depicted in Fig.
6A, a COZ gaseous stream 30 is contacted with the water at precipitation step 20. The provided gaseous stream 30 is contacted with a suitable water at precipitation step 20 to produce a CO2 charged water. By CO2 charged water is meant water that has had CO2 gas contacted with it, where CO2 molecules have combined with water molecules to produce, e.g., carbonic acid, bicarbonate and carbonate ion. Charging water in this step results in an increase in the "CO2 content" of the water, e.g., in the form of carbonic acid, bicarbonate and carbonate ion, and a concomitant decrease in the pC02 of the waste stream that is contacted with the water. The CO2 charged water can be acidic, having a pH of 6 or less, such as 5 or less and including 4 or less.
In some embodiments, the CO2 charged water is not acidic, e.g., having a pH of 7 or more, such as a pH of 7-10, or 7-9, or 7.5-9.5, or 8-10, or 8-9.5, or 8-9. In certain embodiments, the concentration of COz of the gas that is used to charge the water is 10% or higher, 25% or higher, includin g 50% or higher, such as 75% or higher.
[00217] CO2 charging and carbonate mineral precipitation may occur in the same or different reactors of the system. As such, charging and precipitation may occur in the same reactor of a system, e.g., as illustrated in Fig. 6A at step 20, according to certain embodiments of the invention. In yet other embodiments of the invention, these two steps may occur in separate reactors, such that the water is first charged with CO2 in a charging reactor and the resultant CO2 charged water is then subjected to precipitation conditions in a separate reactor. Further reactors may be used to, e.g.;. charge the water with desired minerals.
[00218] Contact of the water with the source CO2 may occur before and/or during the time when the water is subjected to CO2 precipitation conditions. Accordingly, embodiments of the invention include methods in which the volume of water is contacted with a. source of CO2 prior to subjecting the volume of water (e.g., alkaline earth metal ion-containing water) to mineral precipitation.
conditions. Embodiments of the invention also include methods in which the volume of water is contacted with a source of CO2 while the volume of water is being subjected to carbonate compound precipitation conditions.
Embodiments of the invention include methods in which the volume of water is contacted with a source of a CO2 both prior to subjecting the volume of water (e.g., alkaline earth metal ion-containing water) to carbonate compound precipitation conditions and while the volume of water is being subjected to carbonate compound precipitation conditions.
In some embodiments, the same water may be cycled more than once, wherein a first cycle of precipitation removes primarily calcium carbonate and magnesium carbonate i.ninerals and leaves water to which metal ions, for example, alkaline earth metal ions, may be added, and that may have more CO2 cycled through it, precipitating more carbonate compounds.
[00219] Regardless of when the CO, is contacted with the water, in some instances when the CO2 is contacted with the water, the water is not exceedingly alkaline, such that the water contacted with the CO, may have a pH of 10 or lower, such as 9.5 or lower, including 9 or lower and even 8 or lower. In some embodiments, the water that is contacted with the COZ is not a water that has first been made basic from an electrochemical protocol. In some embodiments, the water that is contacted with t.he CO, is not a water that has been made basic by addition of hydroxides, such as sodium hydroxide. In some embodiments, the water is one that has -62- Docket No, CLRA-026W0 been made only slightly alkaline, such as by addition of an amount of an oxide, such as calcium oxide or magnesium oxide.
[00220] As mentioned above, one of the parameters affecting the efficiency of incorporation of gas into a liquid is the solution chemistry of the liquid. Gases will have different solubility specific to a solution based upon the ionic content and the pH of the solution. For example, carbon dioxide gas incorporates more readily into solutions with basic pH, such as an aqueous solution of NaOH, than into solutions with neutral or acid pH. In some embodiments, the gas is the flue gas of an industrial process. In some embodiments, that industrial process comprises the buniing of fossil fuels. In some embodiments, the gas comprises CO2. In these embodiments, the method and apparatus may be tailored to optimize the incorporation of CO2 gas into the liquid from the gas. In such embodimep_ts, conditions are provided (e.g.
solution chemistry, surface area to volume ratio, liquid flow rate to gas flow rate ratio (L/G), residence time) which allow at least 10 grams of COZ to be absorbed per 100 nil of the liquid. In some embodiments, conditions are provided that allow at least 20 grams of CO2 to be absorbed per 100 ml of the liquid, such as at least 30 grams, at least 40 grams, at least 50 grams, at least 60 grams, at least 70 grams, at least 80 grams, at least 90 grams, at least 100 grams, or more than 100 grams of CO2 to be absorbed per 100 ml of the liquid. In some embodiments, the methods and apparatus provide conditions (e.g, solution chemistry, surface are to volume ratio, residence time) where at least 50% of the CO2 in a gas is removed from the gas into the liquid or the shvrry. In some embodiments, conditions are provided which allow at least 60% of the CO2 in a gas to be removed, such as at least 70%, at least 80%, or at least 90% of the CO2 zn a gas is removed from the gas into the liquid or the slurry. In some embodiments, conditions are provided which allow at least 95% of the CO2 in a gas to be removed from the gas into the liquid or the slurry. In sonle embodiments, the methods and apparatus provide conditions (e.g.
solution chemistry, surface are to volume ratio, liquid flow rate to gas flow rate ratio (L/G), residence time) where at least 50% of a component of a gas (e.g. NOx, SOx, mercury) is removed f.rom the gas into the liquid or the slurry. In some embodiments, conditions are provided which allow at least 60% of a component of a gas to be removed, su.ch as at least 70%, at least 80%, or at least 90% of a component of a gas to be removed from the gas into the liquid or the slurry. In some embodiments, conditions are provided which allow at least 95% of a component of a gas is removed from the gas into the liquid or the sluny..
[00221] Optimization of precipitation reactions is one goal of high-efficiency gas-liquid contacting methods and apparatus. In some embodiments, precipitates are formed which include carbonate and/or bicarbonate materials. Precipitates of divalent cation carbonate and'or bicarbonate materi.als are formed in some embodiments. In some embodiments calcium carbonate and./or bicarbonate materials are formed. In some embodiments magnesium carbonate and/or bicarbonate materials are formed. In some embodiments, both calcium and magnesium carbonate and/or bicarbotiate materials are f:,rlne.d.
In some embodiments.
carbonates and/or bicarbonates of both calcium and maanes um, e.g, dolomite, are formed.
[00222] In some embodiments presented herein, streams and/or droplets are formed from a sharry and then are contacted with a gas in the methods and apparatus. The slurry used to make liquid droplets and/or streams -63- Docket No. CLRA-026W0 can depend on what is available at the site where the gas-liquid contactor is located as well as the gas which will contact the droplets and the desired outcome from the interaction between the gas and liquid droplets.
Liquids that can make up the liquid component of the slurry include, but are not limited to: aqueous solutions containing divalent cations with a pH 10 or greater; sea water; brackish water; man-made liquid waste from desalination processes; naturally occurrin.g brines; industrial waste brines;
a synthetic brine; a solution augmented with cations; a solution augmented with silica; or any combination thereof. Compositions of the slurries used can include, but are not limited to, a liquid and industrial waste particulate, a liquid and mineral particulates, a liquid and a precipitate or'combinations thereof. As mentioned above herein, the solution chemistry may be tailored to increa.se the incorporation of gas i.nto the liquid or slurry. In some embodiments, liquid droplets and/or streams comprising an aqueous solution are provided. In some embodiments, liquid droplets and/or streams comprising an aqueous solution of pH between 4 and 11 are provided. Some embodiments provide for liquid droplets and/or streams comprising an aqueous solution comprising ions.
Some embodiments provide for liquid droplets and/or streams comprising an aqueous solution comprising divalent cations. Some embodiments provide for liquid droplets and/or streams comprising an aqueous solution comprising sea water, dissolved mineral solutions, brines or any combination thereof. In some embodiments, liquid droplets comprising a basic solution are provided. In.
some embodiments, liquid droplets and/or streams comprising an alkali metal hydroxide are provided. In some embodiments, liquid droplets and/or streams comprising NaOH or KOH or combinations thereof are provided.
Some embodiments provide liquid droplets and/or streams that comprise solid material. In some embodiments, the liquid droplets and/or streams comprise a precipitated Aaaterial resulting, from contacting the l.iquid droplets with the gas. In some embodiments, the liquid droplets and/or streams comprise particulates of an industrial waste such as, but not limited to, fly ash, slag, cement kiln dust, mining waste, or any combination thereof. In some embodiments, the liquid droplets and/or streams comprise a precipitated material and particulates of an industrial waste. In some embodiments, liquid droplets andlor streams comprising particulates of a mineral are provided. In some embodiments, liquid droplets and/or streams comprising particulates of a niineral and particulates of an industrial waste are provided. In some embodiments, liquid droplets and/or streams comprising particulates of a mineral, particulates of an industrial waste, and a precipitated material are provided.
[00223] There are many wavs to make liquid droplets. Very fine mists of d-roplets can be made using evaporation, such as evaporating water to humidify an area. Non-evaporative technologies for creating droplets include, but are not limited to: pressure atomizers (nozzles), rotary atomizers, air-assisted atomizers, airblast atomizers, ultrasonic atomizers, ink jet atomizers, MEMS atomizers, eductor-jet nozzles, and electrostatic spray atomizers. In embodiments describing liquid and/or slurry droplets, any nlethod of droplet formation may be used. In some embodiments, liquid droplets are made utilizing systems comprising ultrasonic transducers. In some embodiments, liquid droplets are made utilizing systems comprising pressure atomizers (nozzles), rotary atomizers, air-assisted atomizers, airblast atornizers or any combination thereof. In some embodiments, liquid droplet-pr.oducing systems or devices (i.e. liquid introduction units) are provided -64- Docket No. CLRA-026W0 that comprise ultrasonic transducers. In some embodiments, liquid droplet-producing systems or devices are provided that comprise nozzles. In some embodiments, liquid droplet-producing systems or devices are provided that comprise dual-fluid nozzles, eductor-jet nozzles, or both. In some embodiments, liquid droplet-producing systems and/or devices are provided with nozzles that have openings 5 micrometers or less. In some embodiments, liquid droplet-producing systems and/or devices are provided with nozzles that have openings 10 micrometers or less. In some embodiments, liquid droplet-producing systems and/or devices are provided with nozzles that have openings 10 micrometers or more. In some embodiments, liquid droplet-producing systems and/or devices are provided with nozzles that have openings 25 micrometers or more, such as 50 micrometers or more, 100 micrometers or more, 250 micrometers or more, 500 micrometers or more. In some embodiments, liquid droplet-producing systems and/or devices are provided with nozzles that have openings 1 millimeter or more. In some embodiments, liquid droplet-producing systems and/or devices are provided that comprise pressure atomizers (nozzles), rotary atomizers, air-assisted atomizers, airblast atomizers or any combination thereof. Some embodiments provide for systems and/or apparatus that are capable of accepting slurry to create droplets. In some embodiments, systems and/or apparatus that produce liquid droplets are provided, wherein the liquid droplets range from 50 to 1000 micrometers ( m) in diameter.
In some embodiments, systems and/or apparatus that produce liquid droplets are provided, wherein the liquid droplets are of average diameter greater than 1000 micrometers ( m). In some embodiments, systems and/or apparatus that produce liquid droplets are p.rovided, wherein the liquid droplets are of average diameter greater than 500 micrometers. In some embodiments, systems and/or apparatus that produce liquid droplets are provided, wherein the liquid droplets are of average diameter less than 1 micrometer. In some embodiments, systems and/or apparatus that produce liquid droplets are provided where the average diameter of the droplets is greater than 5 micrometers, such as greater than 10 niicrometers, greater than 20 micrometers, greater than 50 micrometers, greater than 100 micrometers, greater than 200 micrometers, greater than 300 micrometers, or greater than 400 micrometers. In some embodiments, systems and/or apparatus that produce liquid droplets are provided where the average diameter of the droplets ranges from 1 to 400 micrometers. in some embodiments, systems and/or apparatus that produce liquid droplets are provided where the average diameter of the droplets is greater ranges from 1 to 500 micrometers. In some embodiments, systems and/or apparatus that produce neutrally buoyant liquid droplets are provided.
Neutrally buoyant liquid droplets are liquid droplets which neither rise nor sink in the environment in which they are neutrally buoyant, e.g. the gas which surrounds the droplets.
[002241 It may be possible to optimize the area of a cross-section of the contacting chamber or column of an apparatus that is covered by droplets by varying the type of droplet pro(lucing technology used. In particular, it may be possible to optimize the area of a cross-section of the apparatus covered by droplets by utilizing sprays of differing angles. In some embodiments, sprays of 60' are used near the walls of the contacting chamber and sprays of 90' are used in the inner cross section of the contacting chamber.

-65- Docket No. CLRA-026W0 [00225] The surface area to volume ratio of a liquid in contact with a gas is one factor that dictates the efficiency of incorporation of the gas into the liquid. In some embodiments, droplets and/or liquid streams are provided that have surface area to volume ratios (SA:V) of 12 m2/liter or more. In some embodiments, droplets and/or liquid streams are provided that have surface area to volume ratios (SA:V) of 24 mz/liter or more, such as 60 m2/liter or more, 80 m2/liter or more, 120 m2/liter or more, 600 m2/liter or more, or 6000 m2/liter or more. In some embodiments, liquid droplets are provided of average diameter greater than 500 micrometers. In some embodiments, liquid droplets are provided of average diameter less than 1 micrometer.
In some embodiments, liquid droplets are provided of average diameter greater than 5 micrometers, such as greater than 10 micrometers, greater than 20 niicrometers, greater than 50 micrometers, greater than 100 micrometers, greater than 200 micrometers, greater than 300 micrometers, or greater than 400 micrometers.
In some embodiments, liquid droplets are provided of average diameter ranging from 1 to 400 micrometers.
In some embodiments, liquid droplets are provided of average diameter ranging from 1 to 500 micrometers.
In some embodiments, liquid droplets are provided of diameter rangin;; from 50 to 1000 micrometers (gm). In some embodiments, liquid droplets are previded of an average diameter of 100 micrometers (gm). In some embodiments, methods that produce and/or utilize neutrally buoyant liquid droplets are provided. Neutrally buoyant liquid droplets are liquid droplets which neither rise nor sink in the environment in which they are neutrally buoyant, e.g. the gas which surrounds the droplets.
[002261 In some embodiments of the ini/ention specific L/G ratios are indicated. The L/G ratio is a number that is the ratio of the flow rate of the liquid to the flow rate of the gas in an apparatus. Without being bound by theory, the absorption of the gas or components of the gas into the liquid are directly proportional to the L/G ratio. In some uses of the ratio, the L/G ratio is a dimensionless number, and as such will indicate a volume flow per unit tim.e relative to another volume flow per unit time or a mass flow per unit time relative to another mass flow per unit time. In some embodiments, the L/G ratio employed ranges from 3 to 50. In some embodiments, the L/G ratio employed ranges from 3 to 20. In some embodiments, the L/G ratio employed is 15. In some embodiments. the IJG ratio employed .ranges from 50 to 4000. In some embodiments, the L/G ratio employed rangt-,s from 100 to 1000. In some embodiments, the L/G ratio employed ranges from 200 to 400. In some embodime:nts, the L/G ratio employed is 300. In some embodiments, the apparatus and/or system is configured to employ a L/G ratio ranging from 3 to 50. In some embodiments, the apparatus and/or system is configured to employ a L/G ratio ranging from 3 to 20. In some embodiments, the apparatus and/or system is configured to employ a. L/G ratio of 15. In some embodiments, the apparatus and/or system is configured to employ a L/G ratio ranging from 50 to 4000. In some embodiments, the apparatus and/or system is, confi~-ured to employ a L/G ratio ranging from100 to 1000. In some embodiments, the apparatus andJor system is confivured to employ a L/G
ratio ranging from 200 to 400.
In some embodiments, the apparatus and/or system is configured to employ a L/G
ratio of 300. In some uses of the L/G ratio, units are cited to i.dent,ify that either volumes or mass are compared in the ratio. In some embodiments, the L/G ratio employed ranges from 0 to 10,00(1 gallons per minute/l 000 actual cubic feet. In -66- Docket No. CLRA-026W0 some embodiments, the L/G ratio employed ranges from 50 to 5,000 gallons per minute/1000 actual cubic feet. In some embodiments, the L/G ratio employed ranges from 100 to 500 gallons per minute/1000 actual cubic feet. In some embodiments, the apparatus and/or system is configured to operate at a liquid flow rate to gas flow rate ratio (L/G ratio) of between 0 and 10,000 gallons per minute/1000 actual cubic feet. In some embodiments, the apparatus and/or system is configured to operate at a liquid flow rate to gas flow rate ratio (L/G ratio) of between 50 and 5,000 gallons per minute/1000 actual cubic feet.
In some embodiments, the apparatus and/or system is configured to operate at a liquid flow rate to gas flow rate ratio (L/G ratio) of between 100 and 500 gallons per minute/1000 actual cubic feet.
[002271 There are structural features that may be added to a chamber in which liquids or slurries and gases are contacted that enhance the incorporation of a gas into a liquid or slurry.
Such structural feathires are meant to increase the interaction between a gas as it flows past a liquid or slurry either by: 1) providing an area or areas for the liquid/gas system to come to equilibrium or 2) allowing the liquid or slurry the opportunity to become entrained by the gas and to follow a more convoluted path as the liquid or slurry passes through the space of the chamber (e.g. as liquid or slurry droplets fall). In some embodiments either type of stnicttual feature is used to contact an absorbing solution, contacting mixture, or slurry with a gas. In some embodiments an apparatus or a system comorises either type of structural feature to contact absorbing solution, contacting mixture, or slurry with a gas. In some, embodiments, or a combination of both types of structural features are used to contact an absorbing solution, contacting mixture, or slurry with a gas. In sonie embodiments an apparatus or a system comprises both types of stnactural featuxe'.o contact absorbing solution, contacting mixture, or slurry with a gas.
[002281 Structural features that increase the probability of a liquid and gas coming to equilibrium within a confined space include packing materials and trays. Packing materials may be structured or not structured, may be ceramic, plastic, or metal spherical, honeycomb shaped, ribbon shaped, saddle shaped, ring shaped or randomly shaped forms. Trays are typically metal sheets with perforations or openings which allow the flow of gas and liquid through the trays. The materials from which packing materials and trays are made are selected based upon the chemistry of the gas, liquid, and products anticipated in the column or reactor as well as concerns such as physical wear. Columns or reactors which utilize packing material or trays can be thought of as a collection of stages (i.e. lengths of the column or reactor) in which the gas leaving the stage is in equilibrium with the liquid leaving the stage. A theoretical staQe describes a physical section of a column where the bulk vapor and bulk liquid phases can be approximated as being in equilibrium with respect to the concentration the species that are exchanged as the gas and liquid traverse the column. The efficiency of a volume can be adjusted by tailoring the packing materials or configuration of trays. Columns or reactors utilizing packing materials or trays are characterized by a high pressure drop across the overall length of the column or reactor due to the liquid head associated with trays or the bed drop associated with packing materials. Columns utilizing packing materials are penera.lly not well suited to contacting slurries with gas, but packing materials have been made commercially available to accommodate slurries. In some -67- Docket No. CLRA-026W0 embodiments, trays, packing material, or both are used to contact an absorbing solution, contacting mixture, or slurry with a gas. In some embodiments, an apparatus or system comprises packing materials, trays or a combination thereof to contact absorbing solution, contacting mixture, or slurry with a gas.
[00229] Membranes are another type of structural feature that may be included in a column or reactor to facilitate the interaction between a gas and a liquid. Membranes that are utilized in columns or reactors are used to increase the interfacial area between a liquid and gas so as to maximize the mass transfer rate.
Membranes may be composed of many hollow fibers. In such membranes, the gas-liquid interface occurs at the entrance to each hollow fiber pore. Thus, membranes of this type may be termed niicroporous membranes. In some embodiments, one or more membranes are used to contact an absorbing solution, contacting mixture, or slurry with ag.;as. In some embodiments, an apparatus or system comprises one or more membranes to contact absorbing solution, contacting mixture, or slurry with a gas. In some embodiments, one or more membranes in combination with packing material and/or trays are used to contact an absorbing solution, contacting mixture, or slurry with a gas. In some embodiments, an apparatus or system comprises one or more membranes in combination with packing material and/or trays to contact absorbing solution, contacting mixture, or slurry with a gas. In some embodiments, one or more microporous membranes are used to contact an absorbing solution, contacting mixture, or slurry with a gas. In some embodiments, an apparatus or system comprises one or more microp~-,irous membranes to contact absorbing solution, contacting mixture, or slurry with a gas. In some embodiments, one or more microporous membranes in combination with packing material and/or trays are used to contact an absorbing soltition, contacting mixture, or slurry with a gas. In some embodiments, an apparatus or system comprises ont-, or more microporous membranes in combination with packing material andlor trays to contact absorbing solution, contacting mixture, or slurry with a gas.
[00230] Structural features that allow liquid or slurry to become entrained within a gas as it is passing through a column or chamber while simultaneously encouraging both the gas and liquid to follow a more convoluted path include shed rows. Shed rows are arrays of sheets of material with a g-eater length than width, typically metal, bent in the middle to form an inverted. "v" shape that are supported by rings. Typically, shed rows are placed such that the location of the sheds alternates with each level ivithin the column or reactor. In this way, the mixture (e.g. a slurry) or liquid. falling from a shed will land near the apex of a shed below it, leading the mixture or liquid to follow a longer, more convoluted path down the length of the column or reactor than it would have in the absence of shed rows The shed rows also influence the flow of the gas through the column or reactor. In the space between the apex of a shed and the bottom of the shed above it is a one where entrainment of the falling inixture or liquid into th: gas may oc,cur. This entrainment increases the amount of time the mixture or liq:aid and gas have to interact within the columri or reactor. Shed rows are compatible with liquids and slurries. The angle of rcpose, which dictates how wide or narrow the sheds are, allows for the use of shed rows with a variety of solutions and to accommodate solid particulates. The steepness of the sheds can be adjusted to allow the liauids or slurries to roll down the tops of the shed at a rate that permits the -68- Docket No. CLRA-026W0 desired interaction with gas in the column or reactor. Shed rows also allow for a lower drop in gas pressure across the height of the column or reactor as compared to those filled with trays or packing material. In, some embodiments, shed rows are present in the apparatus or systems of the invention. In some embodiments, the chamber where absorbing solution and gas are contacted includes shed rows. In some embodiments, the chamber where contacting mixture and gas are contacted includes shed rows. In some embodiments, the apparatus includes a contacting chamber that includes shed rows. In some embodiments, the system includes an apparatus that includes shed rows. In some embodiments shed rows are comprised of concentric circles of sheds. In some embodiments, the cbamber includes protrusions along the walls of the chamber into the center of the chamber. In such embodiments the protnisi.ons resemble halves of sheds that are sloping downwards.
[002311 There are embodiments where it is desirable to condense or coalesce the liquid droplets or fine particulate material after contact with a gas. In such embodiments, various methods can be employed to cause coalescence of the liquid droplets, including but not limited to: variations in temperature, use of an element with additional surface area, the use of an electrostatic precipitator, or use of streams, sheets, or larger droplets of liquid to entrain the liquid droplets after contacting a gas. In some embodiments, a precipitate forms within the liquid droplets while the droplets are still in contact with the gas. In some embodiments where a precipitate is formed within the liquid droplet while still in contact with the gas, an electrostatic precipitator is used to collect and coalesce the liquid droplets based upon the charge on the precipitate within the droplets. In some embodiments, fine particulates are formed, and an electrostatic precipitator is used to collect these particulates.
[00232] In some embodiments, it is necessary to redirect falling liquid or slurry that descennds the height of an apparatus as droplets, streams, or sheets so that the liquid or slurry does not impart excessive energy into a reservoir of liquid or slurry and create a foam. In particular, it is desirable to avoid the creation of a stable foam layer in some embodiments where the stable foam layer may impair the ability of pumps to function optimally. Structural elements may be used to redirect falling liquid or shzrry. In some embodiments, an inverted cone is present within the apparatus to mitigate foaming. The classical method of removing a foam layer is to mechanically break the bubbles that make up the foam layer. In some embodiments, sprays are used in to mechanically break bubbles and mitigate foamin,. In some embodiments, an inverted cone and sprays are used to mitigate foaming.
[002331 In some embodiments, an apparatus of the invention for transferring (i.e. incorporating) a component of a gas into a liquid includes a gas inlet, a chambeY configured to contact t1?_e liquid and gas; a first liquid introduction unit at a first location within the chamber and a second liquid introduction unit at a second location within the chamber for contacting the gas; a reservoir conf.inzred to contain the liquid after it has contacted the gas; an outlet for the liquid after it ha.s contacted the gas, and at least one of the flowing features: i) a least one array of shed rows within the chamber; ii) an anti-foaming device; iii) at least one pump per liquid introduction unit for pumping the liquid through the introduction unit; iv) configuration of the liquid introduction units such that the direction of the flow of the liquid out of the first unit is different -69- Docket No. CLRA-026W0 than the direction of the liquid out of the second unit; v) one or more restriction orifice mechanism release valve) configured to direct liquid flow to at least one of the liquid introduction units, into the gas inlet, or a combination thereof; and vi) varying the area covered by the liquid introduction units. In such embodiments, the liquid introduction units may be sprays, columns of liquid, flat jets of liquid, or a combination thereof. In such embodiments, the shed rows may be configured to redistribute the flow of the gas as it enters the chamber such that the gas flows axially along the chamber to cover a greater area of the cross section of the chamber than the gas flow upon entering the chamber, prior to interacting with the shed rows. In some embodiments, the anti-foaming device may include a cone (e.g. inverted cone) situated over the reservoir. In such embodiments, sprays oriented towards the cone may also be used. In some embodiments, in which the area covered by liquid introduction units is varied, sprays of varying angles may be used. In some embodiments, the pumps used to piunp liquid through the liquid introduction u.~~its are variable frequency drive pumps.
[00234] An exemplary method and system for contacting a gaseous stream and water employs contacting the gaseous stream to a flat jet stream of the water. Thus in some embodiments the invention provides an apparatus for separating carbon dioxide from an industrial waste stream that comprises a gas-liquid contactor that is configured to contact a flat jet stream of a liquid, e.g., water, with all or a portion of the industrial waste stream to dissolve COZ and, in some embodiments, other constituents of the industrial waste stream, and further comprises a unit operably connected to the gas-liquid contactor for producing a solid conlposition that comprises all or a portion of the CO2 dissolved in the water in the contactor, e.g., through evaporation, precipitation, or the like. In some embodiments, the solid composition is a composition that comprises bicarbonates. In some embodiments, the solid composition is a composition that comprises carbonates. In some embodiments, the solid composition comprises carbonates and bicarbonates.
In some embodiments, the solid composition comprises carbonates and/or bicarbonates and also one or more further components of the industrial waste gas, e.g. SOx or a SOx derivative, NOx or a NOx derivative, a heavy metal or derivative thereof, particulates, VOCs or a VOC derivative, or a combination thereof.
[00235]U.S. Patent No. 7,379,487 describes an exemplary flat jet stream/gas contacting system, the disclosure of which is herein incorporated by reference. In some embodiments, contacting a gaseous stream comprising COZ comprises use of the two-phase reactor as described in U.S.
Patent No. 7,379,487. A brief description of the flat jet stream methods and system is provided below.
[00236) In many gas-liquid contacting systems the rate of gas transport to the liquid phase is controlled by the liquid phase mass transfer coefficient, k, the interfac,ial surface area. A, and the concentration gradient, OC, between the bulk fluid and the gas-liquid interface. A practical form for the rate of gas absorption into the liquid is then:

ID = qa = k(;a(p - p;) = ki_a(CL* - Ci ) [002371 where q) is the rate of gas a.bsorptio=l per unit volume of reactor (mole/cm3=s), a is the average rate of absorption per unit interfacial area (mole/cm2=s), a is the gas 1=quid interfacial area per unit volume (cm2/cm3, -70- Docket No. CLRA-026W0 or cm'), p and pi are the partial pressures (bar) of reagent gas in the bulk gas and at the interface, respectively, CL* is the liquid side concentration (mole/cm) that would be in equilibrium with the existing gas phase concentration, p;, and CL (mole/cm;)is the average concentration of dissolved gas in the bulk liquid. kG and kL
are gas side and liquid side mass transfer co;;fficients (cm/s), respeciively.
[00238] In many gas-liquid reaction systerris the solubility of the CL* is very low and control of the concentration gradient is therefore limited. Thus, the primary parameters to consider in designing an efficient gas-liquid flow reactor are mass transfer and the interfacial surface area to reactor volume ratio, which is also known as the specific surface area.
[00239] In certain embodiments, the flat jet gas-liquid contacting system of the invention is a. gas-liquid contacting system that uses the enhanced specific surface area of a flat jet to improve the interaction between the C02-containing gaseous stream witb. the water. e.g., alkaline earth metal ion-containing water. In certain embodiments, a rigid nozzle plate containing a plurality of orifices tha.t generate very thin flat jets is employed. The flat jet orifice has in one configuration a V-shaped chamber attached to the source of the water, e.g., alkaline earth metal ion-containing water. The flat jet orifice may have a pair of opposing planar walls attached to a vertex of the V-shaped chamber. The flat jet nozzle may have a conical nozzle attached to an opposite end of the opposing planar walls as the V-shaped chamber. In another configuration, the jet orifice may have a circular orifice attached to the liquid sour.ce chamber.
The flat jet nozzle may have a V-shaped groove intersecting the circular orifice to create an oval shaped orifice. The flat jet orifice may be oriented perpendicularly, opposed, or parallel to the inlet source of t'~e C02-containing gaseous stream. A
smallest passage of the flat jet nozzles may be larger than 600 microns. The nozzle may produce a liquid flat jet that has a width. that is at least ten times its thickness, or at least 8 times its thickness, or at least 6 times its thickness, or at least 4 times its thickness. The flat jets may be made as thin as 10 microns, e.g., 10-15 microns, 10-20 microns, or 10-40 m.i.crons,.and be separated by less than 1.1, 1.0, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, or 0.2 mm, e.g., less than 1 millimeter to generate high packing,jet densities ((3 = 0.01) and large specific surface areas, a = 10-20 czri'. The thin jet allows more of the water, e.g., alkaline earth metal ion-contai.ning water, to be exposed to the CO2-containing gaseous stream, generating a higher yield of reaction product per unit liquid mass flow than conventional contactors, e.g., greater transfer of COZ and/or other components of the gas stream, such as SOx, NOx, heavy metals, particulates, VOCS', and derivatives and combinations thereof, to the liquid, e.g., water.
[00240] One embodiment of the invention is to provide a gas li.T.xid solid contactor that includes a CO2 charging reactor having a plu.rality of thin flat jet streams, that are closely and uni{ormly spaced, that have high specific surface area, that have uniform jet velocity, that are aerodynamically shaped to minimize gas flow disruption of the liquid jets, orifices that are free from salt obstrurti.on and clogging and that are operated within co-flow, counter-flow and. parallel flow gaseous process :tre~ims. In one embodiment the jets are operated in a cross-flow configuration with the gas, e.g., the jets dron vertically from a nozzle and the gas flow horizontally or near-horizontally across the jets.

-71- Docket No. CLRA-026W0 [00241] The flat jet gas-liquid contacting system of the invention is employed to contact the C02-containing gaseous stream with the liquid, e.g. water, such as alkaline earth metal ion-containing water. The charging reactor includes a chamber with an inlet source for the C02-containing gaseous stream and a flat jet nozzle for a source of liquid, e.g., water such as alkaline earth metal ion-contain:ing water. The nozzle may have a multitude of orifices that have a minimurn dimension that is greater than 200, 300, 400, 500, or 600 microns in length, e.g., greater than 600 microns In length and generate thin flat jets of high specific surface area. The nozzle may have a pair of parallel opposing plates having a second end attached to a conical nozzle. The nozzle may have a pair of V-shaped plates coupled to a first end of the pair of parallel opposing plates. The liquid, e.g., water such as alkaline earth metal-containing water, orifice may produce a flat jet of water that has a width that is at least 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 times its thickness, e.g., at least 10 times its thickness. The source of liquid, e.g. water such as alkaline earth metal-containing water, may be any convenient source (as described above). In certain embodiments., the water source includes a reservoir having an input for water, e.g., alkaline earth metal ion-containing water, such as a pipe or conduit from an ocean.
Where the liquid, e.g., water such as alkaline earth metal ion-containing water, source is seawater, the input is in fluid conununication with a source of seawater, e.g., such as where the input is a pipe line or feed from ocean water to a land based system.
[00242] The gas-liquid contacting system may include a small segment of orifice arrays. The orifices may be staggered such that the jet orifices are seaarated by 1.5-2.5 cm, e.g., 1.7-2.3 cm, e.g. 1.9-2.1 cm, or 2 cm in one direction, 1.5-2.5 mm, e.g., 1.7-2.3 mm, e.g. 1.9-2.1 mm., or 2 mm in another direction and 0.5-1.5 mm, e.g., 0.7-1.3 mm, e.g. 0.9-1.1. mm, or 1 mm diagonally. The orifice has a V-shaped entrance and conical exit channels for jet development. The intersection of the entrance and exit channels creates the orifice. The jet length to jet width ratio may be 5: ]. to 20:1, or 7:1 to 15: 1, or 8:1 to 12:1, or 9:1 to 11:1, or 10:1 with a thickness of 10-100 microns, e.g., 10-20 microns.
[00243] The charging reactor of the invention may include a flat jet gas-liquid contacting system to create a large specific area of water (e.g., alkaline eartb metal ion-containing water). The charging reactor has a C02-containing gaseous stream source (gas reactant) attached to the manifold of the reactor. In certain embodiments, the manifold has a number of holes (openings) that allow the C0,,-gaseous stream jets to enter the charging reactor. The charging reactor also m2.y have an inlet for the water (e.g., water such as alkaline earth metal ion-containing water) ("liquid reactant") that is coupled by a piping to a plurality of flat jet nozzles, which create a flat stream of the water. The flat streams of the water (e.g., alkaline earth metal ion-containing water) interact with the CO,-containing gaseous stream to produce the CQ,-charged water composition, which will be subjected to precipitation conditions.
[00244] In some embodiments, the nozzle of the flat jet gas liquid contacting system of the charging reactor may have a V-shaped chamber that attaches at the vertex to a first end of a pair of opposing plates. A second end of the opposing plates is attached to a conical nozzle. The water (e.g., alkaline earth metal ion-containing water) flows into the V-shaped c?hambers and is forced through the passage between the opposing plates and -72- Docket No. CLRA-026W0 out the nozzle and creates a flat jet. Depending on the nozzle area, jet flow rate and velocity, the jet thickness is on the order of 5 to 100 microns and the width is on the order of 1 to 5 centimeters. As a result, the width to thickness may be significantly greater than a factor of ten. For jet velocities of approximately 10 m/s, the length of the flat jet stream may be fifteen or more centimeters. The narrowest passage vvhere the conical nozzle meets the opposing planar plates is greater than 600 microns. 'This nozzle allows for larger surface area of water (e.g., alkaline earth metal ion-containing water), which significantly increases the efficiency of the transfer of CO2 and other components (e.g., SOx, NOx, particulates, heavy metals, and/or VOCs) between the C02-containing gaseous stream and the liquid sheet. Further, due to large jet surface area and small jet thickness this nozzle produces a very large specific surface area, 10-20 cm-l, which enables a higher volume of contacting between the water and t.h(_ gaseous stream. In addition to increasing the surface area of the water (e.g., alkaline earth metal ion--containing water), the flat jets llave a throat size of 600 microns or larger.
The large throat size of the fl.a.t jets makes it unlikely that they will clog. In some embodiments where clogging is not as much of an issue, the throat size may be small,-,r, .,.g., 50 niicrons or larger, 100 microns or larger, 200 microns or larger, 300 microns or larger, 400 microns or larger, or 500 n:ucrons or larger. The system may also include a component for collecting the water (e.g., alkaline earth metal ion-containing water) and CO?-depleted gaseous stream for :-eiise.
[00245] The CO2-conta.ining gaseous stream is contacted with the water (e.g., alkaline earth metal ion-containing water) by d.irectina, the gas to rontact the flat jet st eam of water. The CO2-containin.g gaseous stream may be flowed in virtually any direction with respect to the flat jet stream, including orthogonal to the flat jet stream, parallel to the flat jet stream, anti-parallel to the flat jet stream, or at an angle to the flat jet stream.
[00246] As reviewed above, the gas from the industrial plant 30 may be processed before being used to charge the water. For example, the gas may be subjected to oxidation conditions to improve solubility of the components of the gaseous stream (e.~;., to convert CO to COZ. NO to NO2, and SOn to SO:., etc.).
[00247] Fig. 11 shows an embodiment of the apparatus of the invention. A
slurry comprising a liquid and a solid component enters the contacting chamber through an inlet conduit [100]
to a reservoir [ 1051 which also contains the slurry that has contacted the gas. In some embodiments, a screw conveyor provides comminution and mixing of the slurry with a gas as it enters the cliamber [110]. In some embodiments, a gas enters the chamber through an inlet [110]. In some embodiments there are at least two levels, or sections, of droplet or stream production [150 and 1551 with conduits for the gas to travel upwards in the chamber [160]
within the arrays of droblet or stream producing systems. A slurry conveyance system [115, 120, 135, 125, 140, 130] moves the slurry from the reservoirs to the droplet or stream producing systems as well as recirculates the slurry within the disti.nc` levels of <iroplet or stream production. Comminution systems [120, 125, 130] provide particle size reduction for th,.~ soli_d. component of the sl.u.rry, thereby improvizig the participation of the solid in the incorporation of the gas into the liquid In some embodiments, the comminution systenis are screw conveyors in the conduits of the slurry conveyance sys, em [115, 145]. In 73- Docket No. CLRA-026W0 some embodiments, a high-efficiency gas-liquid contactor is employed to reniove more of the desired component from the gas stream. Clear liquid, without solids, is provided to the high-efficiency gas-liquid contactor [165] and either very fine droplets or thin sheets of liquid or other high surface area to volume means are used to contact the liquid and the gas. In some embodiments, condensers [170] are needed to have the droplets and/or particulates produced by the high-efficiency gas-liquid contactor fall to the reservoir. The gas after contacting the liquid leaves the chamber [175] and is either passed through another system or released to the air. The liquid after contacting, including precipitate material from the contact between the gas and liquid as well as a minimal amount of the solid component of the slurry leaves the reservoir [180] and is passed to other systems [1851 such as a precipitating tank, dewatering systems, and building fabrication system.
[002481 Fig. 12 shows a flow diagram of an embodiment of a method of the invention. In most embodiments, a slurry comprising a liqtiid and a solid component is provided [200]. The slurry undergoes comminution to reduce the particle size of the solid component as well mix the slurry [205]. Droplets or streams are formed from the slurry [210], and the liquid as drotil_ets or streams, are introduced [215] to the chamber for contacting [220]. Gas is introduced to the contacting chamber [225]. The source of the gas can be an industrial flue gas, such as that from bsarning fossil fuels, such as coal. After the contact, a contacted slurry is formed and is collected in a reservoir in the contacting chamber [230] and part of this contacted slurry is recirculated after c,omminution [235] and part is pumped off for separation of the solids and liquids [240]. The solids are removed and can be used in many applications, including, but not limited to, building materials, as soil stabilization, paint fabrication, and lubricant fabrication. The effluent liquid [245] can have a solution chemistry favorable for use in a high-efficiency gas-liquid contactor [255] which is located in the apparatus to maximize contact with the gas [250] as it moves through the larger droplets and streams to the fmal stage of contacting. The effluent liquid can also be processed using nanofiltration and reverse osmosis [260] to provide mineral and chemical recovery as well as water that niight be suitable as a feed water for desalination or suitable for release into the environment [265]..
[002491 Fig. 13 shows a horizontally configured embodiment of the apparatus of the invention. A gas enters the chamber through an inlet [300]. A slurry comprising a liquid and a solid component is conveyed from a reservoir where the slurry is subjected to comminution [330] and enters the contacting chamber [310] through an array of droplet producing devices [350] to produce sprays of droplets [320] which fill the chamber. In some embodiments there are at least two sections of droplet nroduct.ion that are operably connected such that the gas travels the length of the sections and becomes depleted in a component of the gas over the length of the contacting chaniber. A slurry conveyance system [340, 350, 360, 370] moves the slurry from the contacting chamber to the droplet producing systems as well as recirculates the slurry within the distinct sections of droplet or stream production. A cornm.itnution system within the slurry reservoir [330] provides particle size reduction for the solid component of the slurryõ thereby improving the participation of the solid in the incorporation of the gas into the liquid. The gas after contacting the liquid leaves the chamber and is -74- Docket No. CLRA-026W0 either passed through another system or released to the air. The liquid after contacting, including precipitate material from the contact between the gas and liquid as well as a minimal amount of the solid component of the slurry leaves the contacting chamber [370] and is passed to other systems [380] such as a precipitating tank, dewatering systems, and building fabrication system.
[00250] Fig. 14 shows a horizontally configured embodiment of the apparatus of the invention from an end-on view. A slurry comprising a liquid and a solid component is conveyed from a reservoir where the slurry is subjected to comminution [400] and enters the contacting chamber [410] through an array of droplet producing devices [430] to produce sprays of droplets [440] which fill the chamber. A gas enters the chamber through an inlet and moves through the chamber [450]. In some embodiments there are at least two sections of droplet production that are operably connected such that the gas travels the length of the sections and becomes depleted in a component of the gas over the length of the contacting chamber. A slurry conveyance system [420, 460, 470] nloves the slurry from the contactin,g chamber to the droplet producing systems as well as recirculates the slurry within the distinct sections of droplet or stream production. A comminution system within the slurry conveyance system [460] provides particle size reduction for the solid component of the slurry, thereby improving the participation of the solid in the incorporation of the gas into the liquid. The gas after contacting the liquid leaves the chamber atad, is either passed through another system or released to the air. The liquid after contacting, including precipitate ma`erial from the contact between the gas and liquid as well as a minimal amount of tlle sol.i_d. component of the sluiry leaves the contacting chamber and is passed to other systems [480] such as a precipitating tank, dewatering systems, and building fabrication system.
[00251IFig. 15 shows an embodiment of the invention which includes a gas distribution section, a variable number of contacting sections, and a de-misting or final gas absorption section that is always located at the top of the apparatus. Gas enters the apparatus at the lower-most section, the gas distribution section, above the collected solution. The gas flows up through the apparatus and exits the top of the apparatus. The contacting sections may number from 1 to more tha.n. one, such as two or three or more. The number of contacting sections will be determined based upon the type of final product desired, the absorbing solution or contacting mixture used, the sprays (or other forrn of liquid stream), and optionally, shed rows used. The section just before the gas exits the apparatus is the demisting sectior..
That section. may include a high-efficiency gas absorbing system that uses, for examnle., flat sheets of clear liquid. or very fine droplets, on the order of less than 100gm, such as less than 50 m diameter droplets. In the final section, solution free of particulates will be used to maximize absorption and/or droplet collection.
The chemistry of the solution used in the demisting and final gas absorption section may be different from the solution used in any of the contacting sections. Recirculation of the solution collected at the bottom of the apparatus may include commintition of any solids that may be in the soluticn. Recirculation may also include separating any solids that may exist from the solution and nassina the effluent back to the apparatus, with or without treatment to make up any chemical deficiencies in the solution. The apparatus may be portable in nature, such that the entire apparatus is contained within a shipping container that xnay be shipped via rail. (train), waterways -75- Dor,'cet No. CLRA-026W0 (barge), and/or road (truck). The apparatus may also be modular, such that the different sections may each be contained within a shipping container and stacked or otherwise operably connected to one another.
[00252] Figs. 16 and 17 are schematics of an embodiment of the apparatus of the invention in which shed rows are used. Fig. 16 shows the overall apparatus, with the gas inlet above the lower portion of the apparatus where collected solution will be stored then removed to further processing.
The center section is comprised of shed rows, the configuration for which is indicated in Fig. 17. The upper section of the apparatus shown in Fig. 16 includes a spray to introduce the absorbing solution or contacting mixture to the apparatus and the gas outlet.
1002531 Fig. 18 are schematics of an embodiment of the invention in which the apparatus comprises an array of sprays. Shown are 4 sprays; the sprays are all directed downwards in the vertically oriented apparatus.
The sprays may be made in any convenAent manner including using eductor or eductor -jet nozzles, dual fluid nozzles, a pressure atomizer, a rotary atomizer, an air-assist atomizer, an airblast atomizer, or an ultrasonic atomizer or anv combination thereof. The flow of the gas in the apparatus is upwards, so that all of the sprays encounter the gas flow in a counter-cl,arrer.t fashion. The gas enters t.hti apparatus at the bottom and flows up the length of the apparatus. The apparatus may include a demisting section positioned before the gas outlet (not shown). The absorbinQ solution or contacting -nixture may be clear liquid or it may be a slurry that contains a solid component such as a mineral, industrial waste (e.g. fly ash, cement kiln dust), and/or a precipitated material if recirculation is eniployed.. In the case that recuculation is employed, comminution of any solids in the absorbing solution may occur. The absorbing solution or contacting mixture may include industrial waste brine, naturally occurring alkaline brine, seawater, an artificially composed or synthetic brine, or any combination thereof.
[00254] Fig. 19 is a schematic of an embodiment of the invention in which the apparatus comprises an array of sprays. Shown are 4 sprays, the two center sprays are optional. The topmost spray is oriented such that the liquid (i.e. absorbing solution or contacting mixt.iue) flows counter-c .urent to the flow of the gas. The bottom-most spray is oriented such that the liquid flows cocur-*-ent with the flow of the gas (up the center of the apparatus that is vertically oriented). The gas enters the apparatus at the bottom and flows up the length of the apparatus. The apparatus may include shed rows in nlace of the two aptional sprays in the center of the apparatus. The apparatus may include a demisting section positioned before the gas outlet (not shown). The absorbing solution may be clear liquid or it may be a slurtS, that contains a solid component such as a mineral, industrial waste (e.g. fly ash, cement kiln dust), and/or a precipitated material if recirculation is employed. In the case that recirculation is employed, comminution of any solids in the absorbing solution may occur.
[00255] Fig. 20 shows representations of shed row configurations. On the left hand side are shown top-down, or plan, views of configurations. On the right hand side are show side sections of shed row configurations.
The top-most configuration is the standard configuration of sliec? rows within a cylindrical chamber or column supported by a rin.g. The sheds are staggered such that liquid fa.lling from the upper sheds will arrive near the apex of the sheds below. On the sides where a complete shed woiild not occ.ur, a downward sloping insert is -76- Docnet No. CLRA-026W0 indicated. The middle configuration is that of sheds that are made into ri.ngs that are concentric. These rings of sheds are supported by wires beneath the sheds going from one side of the chamber or column to the other.
The sheds are staggered, again such that lic-uid falling from the upper sheds will arrive near the apex of the sheds below. The bottom-most configuration of shed rows are confgured such that instead of all of the sheds being aligned parallel to each other through the entire height of the chamber or column, every other level of sheds are oriented 90 to the row above and below.
[00256] Another aspect of highly-efficient gas-liquid contacting is the time that the liquid and gas are in contact so that the gas can incorporate into the liquid. In the case of gas bubbles in a liquid column or liquid droplets surrounded by gas, this contact time can also be called residence time. The residence time of liquid droplets in gas can be increased by creating neutrally buoyant liquid droplets, as described above. The residence time of liquid droplets in gas can also be increased by increasing the path length that the droplets follow while in contact with the gas. In some embodiments, the path length is provided by the configuration of the apparatus. Some embodiments utilize convection or movement of the liquid droplets within the contacting compartment to increase the path length, and thus the residence time, of the droplets in contact with the gas. In some embodiments, the path length i.s provided by a conduit joining a compartment where liquid tlroplets are generated with a compartment where liquid droplets are coalesced. Some embodiments provide for liquid droplets to contact a gas along a lor,g path. In some, embodiments, the long path is a helical path, as in Figs. 21A-22B]]. In some embodiments, the gas is introduced into an apparatus with an involuted feed [Fig. 21A: 400, Fig. 2' B: 500, Fig. 22A: 600, Fig. 22B: 7001, such that the gas and the liquid droplets in contact with the gas follow a helical path within. the contacting compartment of the apparatus [Fig.
21A: 410, Fig. 21B: 510, Fig. 22A: 610, Fig. 228: 710]. Some embodiments utilize arrays of gas-inlets [Fig.
21A: 470, Fig. 21B: 540, Fig. 22A: 670, Fig. 22B: 7401 to increase the residence time of liquid droplets in the gas, e.g. in the main contacting compartment.
[00257] A divalent cation-containing solution source and a CO2 -containing gas source may be operably connected to an absorber (e.g., gas-liquid contactor) of a CO2 ! absorber as described herein. The absorber may include any of a number of different designs, including, for example, gas-liquid contactor 321 of Figs. 23A
and 23B. As shown in Fig. 23B, the gas-liquid contactor may be configured with an inlet (310) in the bottom, through which an aqueous solution of divalent cations may be introduced to the gas-liquid contactor. The gas-liquid contactor m.ay also comprise a lieader or manifold 320 (Fig. 23A, Fig.
23B)., into which C02-containing gas (330i) may be introduced. Fig. 23B provides an illustration of a vortex (i.e., turbulent mixing) that may be created in the divalent cation-containing solution when the CO,-containing gas is passed through nozzles 322 (e.g., adjustable nozzles). Although it is not illustrated, the gas-liqljid contactor may comprise a number of additional adjustable nozzles along the length of the gas liquid contactor.
Additional adiustable nozzles may serve to maintain the vortex, especially in systems such as thai illustrated Fig. 23A. The gas-liquid contactor may also be configured to have a conical shape, which shape helps ta maintain and/or enhance the vortex -77- Docket No, CLRA-026W0 created in the header or manifold 320. In such einbodiments, additional adjustable nozzles may be still be desired, especially when enhanced mixing is desired.
[002581 A gas liquid-contactor inay comprise a chamber comprising a plurality of adjustable nozzles, wherein the nozzles are configured to inject an aqueous solution comprising divalent cations into a chamber comprising an atmosphere of C02-containing gas (e.g., flue gas from a coal-fired power plant). As shown in Fig. 24, the nozzle 410 (e.g., plain orifice pressure atomizer, or the like) is configured to direct the divalent cation-containing aqueous solution against jagged surface 420 (i.e., a surface comprising numerous projections) such that the divalent caticn-containin8 solution is dispersed into fine droplets of aqueous solution, effectively increasing the surface area of the incoming divalent cation-containing solution and optimizing the interaction of the divalent ct!tion-containing solution with.
the C02-containing gas. In such embodiments, the nozzles are configfared to operate at low pressure, which low-pressure operation minimizes energy demands of the process. In some embodiments, the nozzle operate at a pressure of less than 15 psi, 50 psi, 100 psi, 200 psi, 400 psi, 800 psi, or 1000 psi. In some embodiments, the nozzles are configured to.have an orifice size of at least 100 microns, ?00 microns, 300 microns, 400 microns, 500 microns, 750 microns, or 1000 microns. At such pressures, the nozzles, together with the jagged surfaceõ are able to produce droplets of divalent cation-containing solution, wherein the d.roplets have an average diameter of less than 0.5 microns, 1 micron, 10 microns, 15 microns, 30 niicrons. 60 ini.crons, 125 m.icrons, 250 microns, 500 microns, 1000 microns, 2000 microns, or 4000 microns.
[002591 Another way in which the contact time between a gas and liauid can be effectively increased is to recirculate one within the other. In some embodimenrs, liquid droplets that have contacted a gas are coalesced into a liquid solution from which droplets are created and contacted with the gas again. In some embodiments, gas that has been contacted with liquid droplets is passed through an arrav of gas-inlets back into the contacting compartment or apparatus [Fig. 21 A: 470, Fig. 21B: 540, Fig. 22A: 670, Fig. 22B: 740].
In some embodiments, both the gas and the liquid are recirculated. In embodiments where methods and = apparatus are provided to increase the contact time between the gas and liquid by increasing the path length of the liquid droplets in the gas, the size of the liquid droplets can vary from an average diameter of 100 micrometers to 1 millimeter or more, such as from a.r. average diameter of 200 micrometers to 1 millimeter, from an average diameter of 300 micrometers to 900 rnicrometers, from an average diameter of 400 micrometers to 900 micrometers, from an average diameter of 400 micro;-teters to 800 micrometers, from an average diameter of 500 micrometers to 900 micrometers, from an average diameter of 500 micrometers to 800 micrometers, from an average diameter of 500 micrometers to 700 macrometers, or from an average diameter of 400 micrometers to 700 micrometers. In some embocliments, liqu,id droplets of average diameter ranging from 500 nvcrometers to greater than l millimeter are provided_ [002601 Some embodiments utilize extended path length, reci.rculation, an.d bigh-surface area techniques in one contacting compartment. In some embodiments, the liquid used. to make the liquid droplets is a slurry and contains solid material. In such embodiments, comminution, mirin2T of plases with size reduction of the solid -78- Docket No. CLRA-026W0 component, is used with recirculation. In some embodiments, the apparatus comprises multiple droplet formation stages, some of which utilize coinminution with recirculation and some of which utilize high-surface area techniques with a liquid that is does not contain solid material before exposure to gas. In some embodiments, the method comprises mixing a solid with a liquid in a manner utilizing comminution;
contacting the solid and liquid mixture, or slurry, with a gas; and separating out the solids from the liquid after contact with the gas. In some embodiments, the slurry is recirculated and contacted with the gas multiple times. In some embodiments, the liquid that has been separated from the solids after the slurry has contacted the gas is recirculated.
[00261] In some embodiments, the apparatus and systems of the invention are configured to incorporate more than 20 tons/hour of carbon dioxide into an absorbing solution as a.veraged over 72 hours of continuous operation. In some embodiments, the apparatus and systemr, of the invention are configured to incorporate more than 40 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the apparatus and systems of the invention are configured to incorporate more than 60 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the apparatus and systems of the invention are configured to incorporate more than 70 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the apparatus and systems of the invent%osi axe configured to incorporate more than 80 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the apparatus and systeins of the invention are configured to incorporate more than 90 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the apparatus and systems of the invention are configured to incorporate more than 100 tons/hour of carbon dioxide into an absorbing solution. In sor:ie embodiments, the apparatus and systems of the invention are configured to incorporate more than 110 tons/hour of carbon dioxide into an absorbing solution. In some embodiments, the apparatus anci systems of the invention are configured to incorporate more than 120 tons/hour of carbon dioxide into an absorbing solution. T.n some embodiments, the apparatus and systems of the invention are configured to incorporate more than. 130 tons/hour of carbon dioxide into an absorbing solution. In some embodiments the apparatus and systems of the invention are configured to incorporate more than 140 ton.s/hour of carbon dioxide into an absorbing solution. In some embodiments, the apparatus and systems of the invention are configured to incorporatc mor.e than 150 tons/hour of carbon dioxide into an absorbing solution. Ln some embodiments the apparatus and systeins of the invention are configured to incorporate more than 160 tons/honr of carbon dioxide into an absorbing solution. In some embodiments, the apparatus and systems of the invention are configared to incorporate more than 170 tons/hour of carbon dioxide into an absorbing solution. Tn some embodiments, the apparatus and systems of the invention are configured to incornorate more than 180 tons/h.our of carbon dioxide into an absorbing solution. In some embodiments, the appara'xic and systems of the invention are configured to incorporate more than 190 tons/hour of carbon dioxide into an absorbing solut.ion. In some embodiments, the apparatus and systems of the invention are configured to ~ncorporate 1nore than. 200 tons/hour of carbon dioxide into an absorbing solution.

-79- Docket No. CLRA-026W0 [002621 In some embodiments, the apparatus and systelns of the invention include a apparatus and systems for removing CO2 from a gaseous source, e.g., an industrial gaseous source of COz such as flue gas from a power plant, or such as exhaust gas from a cement plant, in which the apparatus and systems are configured to subject a water (e.g. a sea water, a brine, an absorbing solution) into which CO, has been dissolved from the gaseous source of CO2 (e.g. an industrial source of carbon dioxide) to precipitation conditions, where the precipitation conditions provide precipitate in an amount of 2.6 grams of precipitate per liter of absorbing solution to 26.11 grams of precipitate per liter of absorbing solution averaged over a period of 72 hours of continuous application of the precipitation conditions. In some embodiments, the apparatus and systems are configured to provide precipitation conditions tha.t provide precipitare in an amount of 5.2 grams of precipitate per liter of absorbing solution to 26.11 grams of precipitate per liter of absorbing solution averaged over a period of 72 hours of continuous application of the precipitation.
conditions. In some embodiments, the apparatus and systenis are configured to provide precipitation conditions that provide precipitate in an amount of 7.83 grams of precipitate per liter of absorbing solution to 26.11 grams of precipitate per liter of absorbing solution averaged over a period of 72 hours of continuous application of the precipitation conditions, such as 9.14 to 26.11, such as 10.44 to 26.11, such as 11 75 to 26.11, such as 13.05 to 26.11, such as 14.36 to 26.11, such as 15.66 to 26.11, su.ch as 16.97 to 26.11, such as 18.27 to 26.11., such as 19.58 to 26.1.1, such as 20.88 to 26.11, such as 22.19 to 2.6.11., such as 23.5 to 26.11, such as 24.8 to 26.11 grams of precipitate per liter of absorbing solution.
[002631 The carbonate mineral precipitation station 20 (i.e., reactor) may include any of a number of different components, such as temperature control components (e.g., configured to heat the water to a desired temperature), chemical additive components, e.g.., for introducing chemical pH
elevating agents (such as KOH, NaOH) into the water, electrolysis components, e.g., cathodes/anodes, etc, gas charging components, pressurization components (for exaniple where operating the protocol under pressurized conditions, such as from 50-800 psi, or 100-800 psi, or 400 to 800 psi, or any other s~aitable pressure range, is desire(t) etc, mechanical agitation and physical stirring components and components to re-circulate industrial plant flue gas through the precipitation plant.
[002641 The carbonate mineral precipitation station. 20 ma.y incllade any of a number of different components that allow for the monitoring (e.g., inline monitoring) of one or more parameters such as internal reactor pressure, pH, precipitate particle size, metal-ion concentration, conductivity of the aqueous solution, alkalinity of the aqueous solution, and pCO2. Monitoring cnnd~tions durin' f2 the carbonate precipitation process may allow for corrective adjustments to be made during the precipitation process.
For exampie, corrective adjustments may be made to increase or decrease carbonate compound precipitation prodl.iction. In some embodiments, the carbonate precipitation process is monitored with an. inline monitoring apparatus operably connected to the carbonate mineral precipitation station, the inline monitoring apparatus comprising a dilution manifold, an ion selective electrode, a voltmeter, a controller, and a, source of diluent. Fia. 25 illustrates one possible inline monitor 1600. Operationally, a controller (1660) controls a variable flow control valve (1621), -80- Docket No. CLRA-026W0 the controller-operated variable flow control valve allowing precipitation station effluent to enter a dilution manifold (1630), typically afler passing through a filter (not shown in Fig.
25) to remove carboiiate mineral precipitate. Undiluted precipitation station effluent is then rneasured for ion concentration. To effect an ion concentration measurement, a voltmeter (1650) coupled to one or more electrodes (1640) selective for a particular ion (e.g., Ca2+ or Mg2+), for example, is employed. Should a measured voltage be outside an accepted voltage range (e.g., outside the linear portion of a plot of voltage vs. ion concentration), the precipitation station effluent in the dilution manifold is diluted with diluent (1610). The controller, operably connected to both the voltmetc-,r and the diluent, tnonditors and logs diluent delivery through a controller-operated variable control valve (1.610). Controlled diluent delivery .is slowed or stopped when voltage readings fall within the accepted range. Depending upon controller-de.termined ion concentration for the ion of interest in the original precipitatior,. station effluer_`, diluent may be added to the precipitation station via variable flow control valve 1612 (e.g., if ion concentra.tion is righ) or precipitation station effluent may be drained from the precipitation station -0a valve 1622 (e.g., if ion concentration is low) occur with concomitant delivery of a more concentrated ion solution through a.n inlet to the precipitation staticn.
[002651 It may be desirable to incorporate one or more components from a gaseous s.tream into an absorbing solution, such as removing carbon dioxide and optionally SOx, IelOx, and other non-CO:.> acid gases from an industrial flue gas, without tLe formation of solid precipitates. In sucb cases, the controllers, monitoring apparatus, and precipitation conditions described in more detail elsf.where herein may be used to optimize incorporation of at least one component from a gas into an absor'oinÃr solution and continue the prevention of the release of the one or more comnonen.ts to the Earth's atniosphere. In cases where incorporation of components of a gaseous stream into an absorbing solution does not lead to precipitation, the resulting solution may be further processed by a system to recover a tiseable absorbing solution or to recover water that is potable or suitable for irrigation pijrposes. Alternatively, in cases where incorporation of components of a gaseous stream into an absorbing solution does not lead to precipitation, the resulting solution may be sent to a retention facility, such as, but not limited to, 2 subterranean ]ocation, including a geological formation such as an aquifer. Such solutions resulting from the inaorporaticn. of components of a, gaseous stream into an absorbing solution may be transported to a retention facility using any convenient method, including, but not limited to, conduits such as pipes or trenc:hes, tanker tmcks, pumps, tanks transported via rail or barge, or a combination thereof.

[002661 As illustrated in Fig. 6A. the precipitati.on prodirct res lti rg from precipitation at step 20 may be separated from the precipitation station effluent at step 40 to produce separated precipitation product. As a freshly separated precipitation product may be dried in a later step, the separated precipitation product may also be a "wet dewatered precipitate." Separation, of the precipitation product from the precipitation station effluent is achieved using any of. a nuinber of convenient approaches, including draining (e.g., gravitational sedimentation of the precipitation product followed by draining), decanting, filtering (e.g., gravity filtration, vacuum filtration, filtration using forced air), centrifuging, pressing, or any combination thereof In some -R 1- Docket No. CLRA-026W0 embodiments, precipitation product is separated from precipitation station effluent by flowing precipitation station effluent against a baffle, against which supematant deflects and separates from particles of precipitation product, which is collected in a collector. In some embodiments, precipitation product is separated from precipitation station effluent by flowing precipitation station effluent in a spiral channel separating particles of precipitation product and collecting the precipitation product in from an array of spiral channel outlets. Mechanically, at least one liquid-solid separation apparatus is operably connected to the precipitation station such that precipitation station effluent may flow from the precipitation station to the liquid-solid separation apparatus (e.g., liquid-solid separation apparatus comprising either a baffle or a spiral channel). The precipitation station effluent may flow directly to the liquid-solid separation apparatus, or the effluent may be pre-treated as described in more detail below.
[00267] Energy requirements for any of the foregoing separation approaches may be fulfilled by adapting the approach to utilize any of a number of e.nergy-containing waste streams (e.g., waste heat or waste gas streams) provided by industrial plants; however, it will be appreciated by a person having ordinary skill in the art that separation approaches requiring less energy are desirable in terms of lessening the carbon footprint of the invention.
[00268] Concentration and separat.ion. of the precipitation product from the precipitation station effluent may be achieved continuously or batch wise with methods and liquid-solid separation apparatus described in WO
2007/051640 and CA 02628270, the disclosures of wbich are incorporated herein by reference. In some embodiments, the liquid-solid separation apparatus comprises a container having a fixnnel shaped section, a precipitation station effluent pipe arran?ed in the container to extend in a longitudinal direction and opening into the container through an inlet opening for introducing t:he precipitation station effluent flow falling through the precipitation station effluent pipe, and a removal opening formed at the lower end of the funnel-shaped section for removing separated precipitation product from the container characterized by a baffle arranged in the region of the inl.et opening bywhich the precipitation station effluent flow is deflected.
Liquid-solid separators such as Epuramat's Extrem-Separator ("ExSep") liquid-solid separator, or a modification thereof, are useful in sof.n.e embodirnents for separation of the precipitation product from precipitation station effluent.
[00269] To separate precipitation product from the water, the precipitation station effluent is introduced in the direction of gravity into a bath, in which precipitation product particles descend under the action of gravity and are removed from the lower region thereof. This removal of the precipitation product particles may be performed continuously or batch-wise. Precipitation station effluent, upon its ir_troduc.tion into the bath, is flowed against a baffle, by which the flow in the bath is deflected. By this process control a hydraulic-physical reaction zone is generated in the region of the inlet opening, in which at least the predominant flow energy of the precipitation station effluent flowing in the direction of gravity is destroyed. Deflecting the precipitation station effluent flow flowing into the precipitation station effluent pipe in a vertical direction favors the separation of the precipitation product particles due to the density differences over the water. On -82- Docket No. CLRA-026W0 deflecting the precipitation station effluent, the heavier precipitation product particles have a greater tendency to continue their path of motion in the direction of the precipitation statioti effluent pipe (i.e., in the downward direction, while the water is deflected and, separated from the heavy precipitation product particles, ascends.
The destruction of the flow energy is substantially caused by the deflection losses when flowing against the baffle (i.e., in the flow direction of precipitation station effluent flowing tlirough the precipitation station effluent pipe on and predominantly after exiting the precipitation station effluent pipe downstream of the baffle. Precipitation station effluent is particularly deflected in such a way that precipitation product particles (i.e., particles having a higher density than the water, which, generally, are to descend with the container continue their descending motion initiated bv the precipitation station effluent pipe during the introduction in to the bath in a substantially undisturbed manner. The deflection should not have the result that the precipitation product particles having high.er density, that is, the p.-ecipitation product particles have an upwardly directed speed compound imposed on. them during the deflection. Such speed component should solely be imposed on the light water during t:he deflection so that as a result of the deflection at the baffle, the water receives the desired speed component for ascending in the bath.
[00270] Alternatively, concentration. and separation of the precipitation product from the precipitation station effluent may be achieved conti.nuously or batch wise with methods and liquid-solid separation apparatus described in US 2008/018331, the disclosure of which is incorporated herein by reference. In some embodiments, the liquid-solid separation apparatus cornprises an inlet operative to receive precipitation station effluent; a channel operative to allow flow of the precipitatio-l st.atior. effluent, the channel being in a spiral configuration; a separating means for separating precipitation product frorn precipitation station effluent; and at least one outlet for precipitation product-depleted supernatant. Liquid-solid separators such as Xerox PARC's spiral concentrator, or a modification th.ereof ar.e usefizl ir_ some embodiments for separation of the precipitation product from precipitation station efflueTlt.
[00271] Precipitation prodi.ict is separated from the nrecipitation station effluent based on size and mass separation of precipitation product particles, which are made to flow in a spiral channel. On the spiral sections, the inward directed transverse pressure field from fluid shear competes with the outward directed centrifugal force to allow for separation of precipitation product particles.
At high velocity, centrifugal force dominates and precipitation product particles move outward. At low velocities, transverse pressure dominates and the precipitation product narticles move inward. The magnitudes of the two opposing forces depend on flow velocity, particle size, radius of curvature of the spiral sec;tion, channel dimensions, and viscosity of the precipitation station effluent. At the end of the spiral channel, a. parallel array of ontlets collects separated particles of precipitation product. For any particle size, the required channel dimension is determined by estimating the transit time to reach the side-wall. THs time is a function of flow veloeity, channel width, viscosity, and radius of curvature. Larger particles of precin itation product may reach the channel wall earlier than the smaller particles which need more time to reach the side wall. Thus, a spiral channel may have -83- Docket No. CLRA-026W0 multiple outlets along the channel. This technique is inherently scalable over a large size range from sub-millimeter down to 1 micron.
[0027211t may be desirable to pre-treat (e.g., coarse filtration) the precipitation station effluent to remove large-sized particles of precipitation product from the effluent prior to providing the effluent to the liquid-solid separation apparatus as large-sized particles may interfere with the liquid-solid separation apparatus or process. Separation of the precipitation product from the precipitation station effluent may be achieved with a single liquid-solid separation apparatus. In some embodiments, a combination of two, three, four, five, or more than five liquid-solid separation apparatus may be used to separate the precipitation product from the precipitation station effluent. Combinations of liquid-solid separators may be used in series, parallel, or in combination of series and parallel depending on desired throughput. In some embodiments, liquid-solid separation apparatus or combinations thereof are capable of processi.ng precipitation station effluent at 100 L/min to 2,000,000 L/min, 100 L/min to 1,000.,000 L.!min, 100 L%inin to 500,000 L/min, 100 L/min to 250,000 L/min, 100 L/min to 100,000 Lhnin, 100 I./min to 50,000 L/min.. 100 L/mi.n to 25,000 L/min, and 100 L/min to 20,000 L/min. In some embodiments, liquid-solid separation apparatus or combinations thereof are capable of processing precipitation station effluent at 1000 L/min. to 2,000,000 Lhnin, 5000 L/min to 2,000,000 L/min, 10,0000 L/min to 2,000,000 L/mir_. 20.,000 L./min to 2,000..000 L/min., 25,000 L/min to 2,000,000 L/min, 50,000 L/min to 2,000,000 L/niin, 100,000 L/min to 2,000,000 L/min, 250,000 L/min to 2,000,000 LJmin, 500,000 L/min to 2,000.000 I./m;r)., and 1,000,000 L/min to 2,000,000 L/min. In some embodiments, liquid-solid separation apparatus or combina:ions thereof are capable of processing precipitation station effluent at 1000 L/min to 20,000 L./min, 5000 L/min to 20,000 L/min, 10,000 L/min to 20,000 L/min, 1000 L/min to 10,000 L/min, 2000 L/min to 10.000 L/min. 3000 L/rnin to 10,000 L/min, 4000 IJmin to 10,000 L/min, 5000 L/min to 10,000 Lhnin, 6000 L=/min to 10,000 L/min, 7000 L/min to 10,000 L/min, 8000 L/min to 10,000 L/min, 9000 Limin to 10,000 .L/min., or 9500 I,/min to 1.0,000 L,/min.
[002731 Combinations of liquid-solid senarators in series, parallel, or in combination of series and parallel may also be used to increase separation efficiencies. In addition, t?ie supernatant resulting from one or more liquid-solid separation apparatus may he recirculated tlhrough the liqui.d-solid separation apparatus to increase separation efficiency. In some embodiments, 30% to 100%, 40% to 100%. 50% to 100%, 60% to 100%, 70%
to 100%, 75% to 100%, 80% to 100%,, 85% to 100%, 90% to 100%., 95% to 100%, 96% to 100%, 97% to 100%, 98% to 100%, 99% to 100% of precipitation product is collected from the precipitation station effluent. Depending on the amount of precipitation product removed from the precipitation station effluent, the supematant may be delivered back to tr.e precipitation station or provided to an electrolytic cell of the invention. In some embodiments, sunernz.tant with. a-elatively hi~.h concentration. of precipitation product is delivered back to the precipitation station for arglnmeration of nreGipitation prnduct nartieles. In some embodiments, supernatant with a. relativel.v high concontration of clissolved dii/alent cations (e.g., Ca2+ or Mg2+) is delivered back to the precipitation station as a source of divalent cations. In some embodiments, supernatant with a relatively low concentration of nrecir.i.ta.tion procluct and dissolved divalent cations is -84- DcH;ket No. CLRA-026W0 filtered to remove a substantial amount of the rernainiitg divalent czitions and provided to an electrolytic cell of the invention.
[00274] This removal of the precipitation product particles may be per::ornied continuously or batch-wise.
[00275] In some embodiments the precipitation product is not sep~trated, or is only pai-tially separated, from the precipitation station effluent. In such embodiments, the effluent, including sanie (e.g., after passing through a liquid-solid separation apparatus) or all of thr; preeipitation product, may be disposed of in any of a number of different ways. In some embodiments, the effluent from the precipitation station, including some or all of the precipitation product, is transported to a land or water location and deposited at the location, Transportation to the ocean is especially useful in embodiments wherein the source of water is seawater. It will be appreciated that the carbon footprint, amount of energy us~,d. a:idJer amount of CO2 produced for sequestering a given amount of CO12 from an indiastrial exbaust gas is miniinizQd in a nrocess where no further processing beyond disposal occurs with the p:-ecipitate.
[00276] In the embodiment illustrated in Fi;;. 6A, the TMesultant deviate.red precioitate is then dri,ed to produce a product, as illustrated at step 60 of Fig. 6A. Drying can be achieved by air drying the filtrate. Where the filtrate is air dried, air drying may be at room or elevated temperature. In certa.in embodiments, the elevated temperature is provided by the industrial plant gaseous waste stream, as illustrated at step 70 of Fig. 7. In these embodiments, the gaseous waste stream (e.g., flue gas) from the power plant may be first used in the drying step, where the gaseous waste stream may have a tcmnerature ranging from 30 to 700 C., such as 75 to 300 C. The gaseous waste stream may be contacted directly with the wet precipitate in the drying stage, or used to indirectly heat gases (such as air) in the dr},ing stage. The desired temperature may be provided in the gaseous waste stream by having the gas cowieyer, e.g., duct, from the industrial plant originate at a suitable location, e.g., at a location a certain distance in the HRSG or up the flue, as determined based on the specifics of the exhaust gas and configuration of the industrial plant. In yet another embodiment, the precipitate is spray dried to dry the precipitate, where the liquid containing the precipitate is dried by feeding it through a hot gas (such as the gaseous waste stream from the indust--ia1 plant), e.g., where the liquid feed is pumped through an atomizer into a main drying chamber and hot gas is passed as a co -current or counter-current to the atomizer direction. In certain embodiments, drying is achieved by freeze-drying (i.e.,, lyophilization), where the precipitate is frozen, the surrounding press,a.re is reduced and enough hea' is added to allow the frozen water in the material to sublime directly from the frozen precipitate phase to gas.
Depending on the particular drying protocol of the systenl, the dryina statiori may include afiltr.ation element, freeze drying structure, spray drying structure, etc.
[00277] Where desired, the dewatered precipitate product from the separation.
reactor 40 may be washed before drying, as illustrated at optional step 50 of Fi g. 6A. `I'he precipitate zr..ay be washed with freshwater, e.g., to remove salts (such as NaCI) frotn the dewatered precipitate tTsed wasli water rnay be disposed of as convenient, e.g., disposing of it in a tailings pond, etc.

Rti' Docket No. CLRA-026W0 [00278] In certain embodiments of the invention, the precipitate can be separated, washed, and dried in the same station for all processes, or in different staticns for all processes or any other possible combination. For example, in one embodiment, the precipitation and separation may occur in pr=ecipitation reactor 20, but drying and washing occur in different reactors. In yet another embodiment, precipitation, separation, and drying may occur all in the precipitation reactor 20 and washing occurring in a. different reactor.
[00279] Following separation of the precipitate from the, mother liquor, e.g., as described above, the separated precipitate may be further processed as desired. In certain embodiments, the precipitate may then be transported to a location for long terrn storaae, effectively sequesteri.llc_'CO2. For example, the precipitate may be transported and placed at long term storage sites. e.g., above ground, below ground, i..n the deep ocean, etc.
as desired.
1002801 The dried product may be disposed of in a nurn.ber of different ways.
In certain embodiments, the precipitate product is transported to a location for long term storage, effectively sequestering COZ in a stable precipitated product, e.t*., as a storage-stable above ,aroR.rnd CO,-seqnestering material. For example, the precipitate may be stored at a long term storage site adjacent to thi-industrial plant and precipitation system.
In yet other embodiments, the precipitate may be transported and placed at long term storage sites, e.g., above ground, below ground, etc. as desired, where the long term storage site is distal to the power plant (which may be desirable in embodiments where real estate is scarce in the vicinity of the power plant). In these embodiments where the precipitate is transported to a long term storage site, it may be transported in empty conveyance vehicles (e.g., barges, train cars, truck.s, etc.) that were employed to transport the fuel or other materials to the industrial plant and/or precipitation plant. In tris manner, conveyance vehicles used to bring fuel to the industrial plant, materials to the nrecipitatic-n plant (e.g., alkali sources) m.ay be employed to transport precipitated product, and therefore sequester COZ from the industrial plant.
[00281] In certain embodiments, the composition is disposed of in an underwater location. Underwater locations may vary depending on a particular application. While the underwater location may be an inland underwater location, e.g., in a lake, inclnding a fi=eshwater lake, or interest in certain embodiments are ocean or sea underwater locations. The com-nosition may be still in the mothPr ltquor. without seDaration or without complete separation, or the composition may have beer separated from the mother liquor. The underwater location may be shallow or deep. Shallow locations are locations whir,h are 200 feet or less, such as 1-50 feet or less, including 1000 feet or less. Deep lrxatior.s are those that are 200 feet or more, e.g., 500 feet or more, 1000 feet or more, 2000 feet or more, includ.ing, 5000feet or more.
[00282] Where desired, the compositions made un of the precipitate and the mother liquor may be stored for a period of time following precipitation and prior to eisposal, For example, the composition may be stored for a period of time ranging from 1 to 1000 davs or lon.Qer, such as I to 10 days or longer, at a temperature ranging from l C to 40 C, such as 20 C to 25 C.
[00283].Any convenient protocol foN transporting the composition to th; site of disposal may be employed, and will necessarilv vary depending on the locations of the nrecipitation reactor and. site of disposal relative to `h- Docket No. CLRA-026W0 each other, where the site of disposal is an above ground or below gound site disposal, etc. In certain embodiments, a pipeline or analogous slurry conveyance structure is einployed, where these approaches may include active pumping, gravitational niediated flow, etc., as desired.
1002841 While in certain embodiments the precipitate is directly disposed at the disposal site without further processing following precipitation, in yet other embodi_ments the composition may be further processed prior to disposal. For example, in certain embodiments solid physical shapes inay be produced from the composition, where the resultant shapes are then disposed of at the disposal site of interest. One example of this embodiment is where aztificia.l reef stnictures are produced from the carbonate compound eompositions, e.g., by placing the flowable composition in a suitable mold structure and allowing the composition to solidify over time into the desired shape. The resultant solid reef structures may then be deposited in a suitable ocean location, e.g., a shallow underwater locations, to -.-)roduce an artificial reef, as desired.
[00285] In certain embodiments, the precipitate produced by the methods of the invention is disposed of by employing it in an article of manufacture. In other words, the product is employed to make a man-made item, i.e., a manufactured item. The product may be em-oloyed by itself or combined with one or more additional materials, such that it is a corrponent of the r.*.manufactiired items.
Mam2far,tured items of interest may vary, where examples of manufactured items of interest incYtzde building materials a.nd non-biulding materials, such as non-cementitious manufactured items. Ruilding materials of interest include components of concrete, such as cement, aggregate (both fine and coarse), supplementary cementitious materials, etc. Building materials of interest also include pre-fornled building material.s.
[00286] Where the product is disposed of by incorporating the product in a building material, the CO2 from the gaseous waste stream of the industrial plant is effectively sequestered in the built environment. Examples of using the product in a building material include instances where the product is employed as a construction material for some type of manmade structure, e.g., buildings (both commercial and residential), roads, bridges, levees, dams, and other manmade structures etc. The building mab:rial may be employed as a structure or nonstructural component of such structures. In such embodiments, the precipitation plant may be co-located with a building products factory.
[00287] In certain embodiments, the precipitate product is refined (i.e., processed) in some manner prior to subsequent use. Refinement as illustrated in step 80 of Fig. 6A may include a variety of different protocols. In certain embodiments, the product is subjected to mechanical refinement, e.g., grinding, in order to obtain a product with desired phvsical properties, e.g., particle size, etc. In certain embodiments, the precipitate is combined with a hydraulic cement, e.g., as a supplemental cementitious material, as a sand, a gravel, as an aggregate, etc. In certain embodiments, one or more components may be added to the precipitate, e.g., where the precipitate is to be employed as a cement, e.g., one or more additives, sands, aggregates, supplemental cementitious materials, etc. to produce final product, e.g., concrete or mortar, 90.
[00288] In certain embodiments, the carbonate compou?id precipitate is utilized to produce aggregates. Such aggregates, methods for their manufacture, and use thereof are described in co-pendin¾ U.S. Patent -87- Docket No. CLRA-026W0 Application Publication No. US 2010-0024686 Al, published 4 February 201.0, which is incorporated herein by reference in its entirety.
[00289] In certain embodiments, the carbonate compound precipitate is employed as a component of hydraulic cement. The term "hydraulic cement" is employed in its conventional sense to refer to a composition that sets and hardens after combining with water. Setting and hardening of the product produced by combination of the cements of the invention with an aqueous fluid result from the production of hydrates that are formed from the cement upon reaction with water, where the hydrates are essentially insoluble in water. Such carbonate compound cotnpor_ent hydraulic cements, methods for their manufacture and use are described in co-pending U.S. Patent Application Publication No. US 2009-0020044 Al, published 22 January 2009, which is incorporated herein by reference in its entirety.
1002901 Also of interest are formed building materials. The formed building materials of the invention may vary greatly. By "formed" is meant shaped., e.g., molded, cast, cut or otherwise produced, into a man-made structure defined physical shape, i.e., configuration. Formed building materials are distinct from amorphous building materials, e.g., particulate (such as powder) compositions that do not have a defined and stable shape, but instead conform. to the container in which they are held, e.g., a bag or ot.her container. Illustrative formed building materials include, but ane not l.imite,d to: bricks; bo:irds;
conduits; beams; basins; columns;
drywalls; etc. Further examples and details regarding formed building materials include those described in U.S. Patent Application No. 12/571.398, filed 30 September 2009, which is incorporated herein by reference in its entirety.
[00291] Also of interest are non-cementitious manufactured items that include the product of the invention as a component. Non-cementitious manufactured items of the invent;on may vary greatly. By non-cementitious is meant that the compositions are not hydraulic cements. As such, the compositions are not dried compositions that, when combined with a setting fluid, such as water, set to produce a stable product.
Illustrative compositions include, but are not limited to: paper products:
polymeric preducts; lubricants;
asphalt products; paints; personal care products, s;ich as cosmetics, toothpastes, deodorants, soaps and shampoos; human ingestible products, including both liquids and solids;
agricultural products, such as soil amendment products and animal feeds; etc. Further examples and details non-cernentitious manu.factured items include those described in U.S. Patent Application No. 12!609,491, filed 30 October 2009, which is incorporated herein by reference in its entiretv.
[00292] The resultant mother liquor ma.,y a] so be processed as desired. For example. the inother liquor may be returned to the source of the water, e.g., ocean, or to another location. In certain embodinients, the mother liquor may be contacted with a source of CO2. e.g., as (lescribed abovo, to sequester fiirther CO2). For example, where the mother liquor is to be returncd to the ocean.'he mother liquor may be contacted with a gaseous source of COZ in a manner sufficient to increase the conc.cnt.ration of carbonate ion present in the mother liquor. Contact may be conducted. using any conv,,nient l;roi:oco], such as those described above. In certain embodiments, the lnother liquor has an alkaline pH, and contact with the CO2 source is carried out in a Q ~' I)oclcet No. CLRA-026W0 manner sufficient to reduce the pH to a range between 5 and 9, e.g., 6 and 8.5, including 7.5 to 8.2.
Accordingly, the resultant mother liquor of the reaction, e.g., mineral carbonate depleted water, may be disposed of using any convenient protocol. In certain embodiments, it may be sent to a tailings pond for disposal. In certain embodiments, it may be disposed of in a naturally occun-ing body of water, e.g., ocean, sea, lake, or river. In certain embodiments, it may be employed as a coolant for the industrial plant, e.g., by a line running between the precipitation system and the industrial plant. In certain embodiments, it may be employed as grey water, as water input for desalination and subsequent use as fresh water, e.g., in irrigation, for human and animal consumption, etc. Ac;cordingly, of interest are configurations lvhere the precipitation plant is co-located with a desalination plant, sucb that output water from the precipitation plant is employed as input water for the desalination plant.
1002931 As mentioned above, in certain em.bodimerts the mother ?.ic,uor produced. by the precipitation process may be employed to cool the power plant that supplies the source of C02, e.g., in a ona.,e through cooling system. In such embodiments, heat picked up in thF process may then be recycled back to precipitation plant for further use, as desired. In such embodiments, the initi.al water source may come from the industrial plant.
Such embodiments may be modified to employ pumping capacity provided by the industrial plant, e.g., to increase overall efficiencies.
[00294] Where desired and subsequent to the production of a CO.,-sequestering product, e.g., as described above, the amount of CO2 sequestered in the product is quantified. By "cluartified" is meant determining an amount, e.g., in the form of a numeric value, of CO, that has been stqnestered (i.e., fixed) in the CO?-sequestering product. The determination -nay be an absolute quantification of the produ.ct where desired, or it may be an approximate quantification, i.e., not exact. In some embodiments, the quantification is adequate to give a market-acceptable measure of the amount of COZ sequestered.
[002951 The amount of CO2 in the C02-sequestering product may be quantified using any convenient method.
In certain embodiments the quantification may be done by actual measurement of the composition. A variety of different methods may be employed in these embodiments. For example, the mass or volume of the composition is measured. In certain embodiments, such measurement ca.n. be taken while the nrecipitate is in the mother liquor. In these cases, additional methods such as x-ray diffraction rnay be used to auantifv the product. In other embodiments, the measurement is taken after the prr.cipitate has been waslied and/or dried.
The measurement is then used to quantify the amount of CO2 sequestered in the product, for example, by mathematical calculation. For example, a Coulometer ni.a,y be used to obtain a~eading of the amount of carbon in the precipitated sequestration product. This Coulometer reading may be used to determine the amount of carbonate in the precipitate, which may the~-:~ be converted into CO-7 sequestered by stoichiometry based on several factors, such as the initial metal ion content of ttie water, the limiting reagent of the chemical reaction, the theoretical vield of the starting materials of the reaction, water.s of hydration of the precipitated products, etc. In some embodiments, contaminants may be present in the product, and other determinations of -89- Docket No. CLRA-026W0 the purity of the product, e.g., elemental analysis, niay be necessary to determine the amount of CO2 sequestered.
[00296] In yet other embodiments, an isotopic method is employed to deterniine the carbon content of the product. The ratio of carbon isotopes in fossil fuels is substantially different than the ratio of such isotopes in geologic sources such as limestone. Accordingly, the source or ratio of sources of carbon in a sample is readily elucidated via mass spectrometry that quantitatively measures isotopic mass. So even if limestone aggregate is used in concrete (which will increase total carbon determined via coulometry), the utilization of mass spectrometry for isotopic analysis will allow e!uc'Edation of the amourt of the carbon attributable to captured CO2 from fossil fuel combustion. In this manner, the amount of carbon sequestered in the precipitate or even a downstream product that inconiorates the precioitate, e.g..
concrPte., may be determined, particularly where the COZ gas employed to make the precipitate is obtained from ::ombustion of fossil fuels, e.g., coal.
Benefits of this isotopic approach include the ability to determine carbon content of pure precipitate as well as precipitate that has been incorporated into another product, e.g., as an aggregate or sand in a concrete, etc.
[00297] In other embodiments, the quantification may be done by making a theoretical determination of the amount of CO, sequestered, such as by calculating t'ie ainount of CO2 sequestered. The amount of COZ
sequestered may be calculated by using a known yield of the above-described method, such as where the yield is known from previous experimentation. The known yield may liarv according to a number of factors, including one or more of the input of gas (e.v. CO7) and water, *he concentration of metal ions (e.g., alkaline earth metal ions), pH, salinity, temperat?ir.e, the rate of the gaseous stream, the embodiment of the method selected, etc., as reviewed above. Standard information, e.g., a predetermined amount of CO sequestered per amount of product produced by a given reference process, may be used to readily determine the quantity of CO2 sequestered in a given process that i.s the same or approximately sirnilar to the reference process, e.g., by determining the amount produced and then calculatinL the amount of CO, thE.t mLUt be sequestered therein.

1002981 Aspects of the invention further include systems, e.g., processing plants or factories, for sequestering C02, e.g., by practicing methods as described above. Systems of th., inveiition may have any configuration that enables practice of the particular production method of interest.
[00299] In some embodiments, the invention provides a system for processing carbon dioxide as shown in Fig. 1, wherein the system comprises a processor (1 10) configured for an aqueous-based process for processing carbon dioxide from a source of carbon dioxide (130) using a source of proton-renioving agents (140), and wherein the source of carbor dioxide comprises one or more additional components in addition to carbon dioxide. As shown in Fig. l, the system may fiirl:her com.pr=ise a source of divalent cations (150) operably connected to the pa=ocessor. The processor may comprise a contactor such as a gas-liquid or a gas-liquid-solid contactor, wherein the contactor is configured for charging an aqueous solution or slurry with carbon dioxide to produce a carbon dioxide-charged composition. which composition may be a solution or -90- Docket No. CLRA-026W0 slurry. In some embodiments, the contactor is configured to produce compositions from the carbon dioxide, such as from solvated or hydrated forms of carbon dioxide (e.g., carbonic acid, bicarbonates, carbonates), wherein the compositions comprise carbonates, bicarbonates, or carbonates and bicarbonates. In some embodiments, the processor may further comprise a reactor configured to produce compositions comprising carbonates, bicarbonates, or carbonates and bicarbonates from the carbon dioxide. In some embodiments, the processor may further comprise a settling tank configured for settling compositions comprising precipitation material comprising carbonates, bicarbonates, or carbonates and bicarbonates.
As shown in Fig. 2, the system may further comprise a treatment svstem (e.a., treatment system 120 of Fig. 2) configured to concentrate compositions comprising ca.rbonates, bicarbonates, or carbonates and bicarbonates and produce a supernatant;
however, in some embodiments the cotn.oositions are used without ftuther treatment. For example, systems of the invention may be configured to directly tise compositions from the processor (optionally with minimal post-processing) in the manufacture of building materials. 1n another non.-limiting exa.mple, systems of the invention may be configured to directly injec.~ comuositions from, the processor (optional.ly with minimal post-processing) into a subterranean site as described in U.S. Provisional Patent Application No. 61/232,401, filed 7 August 2009, which is incorporated herein by reference in its entirety. The source of carbon dioxide may be any of a variety of industrial sources of carbon dioxide, ir.clu.ding, hU.t not limited to coal-fired power plants and cement plants. The source of proton-removing agents may be any of a variety of sources of proton-removing agents, including, but not limited to, natural sources of proton-removin.e agents and industrial sources of proton-removing agents (includir.g industrial waste sour.ces). Th.e source of divalent cations may be from any of a variety of sources of divalent cations, including, but not limited to, seawater, brines, and freshwater with added minerals. In such embodiments, the source of divalent cations may be operably connected to the source of proton-removing agents or directlv to the procpssor. In some embodiments, the source of divalent cations comprises divalent cations of allcal.i .e earth metals (e.g., Ca2+, Ma2+).
[00300] Systems of Iffie invention such as that shown in Fig. 1 may forther comprise a treatment system. As such, in some embodiments, the invention provides a svstenl for processing carbon dioxide as shown in. Fig.
2, wherein the system comprises a proc,;s..or (110) and a treatment system (12.0) confgured for an aqueous-based process for processing carbon dioxide from a source of carbon d'oxide (130) u.si.nR a source of proton-removing agents (140), and wherein the source of carbon dioxide comorises one or more additional components in addition to carbon dioxide. As with Fi.g. 1, the system of Fig.
2 may fitrther cor.iprise a source of divalent cations (150) operably conr.ected to the processor. The nroces5or may coniprise a contactor such as a gas-liquid or a gas-liquid-solid contactor, wherein the contactor is confi.mired for charging an aqueous solution or slurry with carbon dioxide to produce a carbon dioxidP-c:harged comnosltzon, which composition may be a solution or slurry. In sorne embodiments, the contactor is configured to produce compositions from the carbon dioxide, such as from solvated or llvdrated farms of carbon dioxide (e.ff., carbonic acid, bicarbonates, carbonates), wherein the compositions comprise carbonates, bicarbonates, or carbonates and bicarbonates. In some embodiments, the processor may further comprise a reactor configured to produce -91- Docket No. CLRA-026W0 compositions comprising carbonates, bicarbonates, or carbonates and bicarbonates from the carbon dioxide.
In some embodiments, the processor may fui-ther comprise a settling tank configured for settling compositions comprising precipitation material comprising carbonates, bicarbonates, or carbonates and bicarbonates. The treatment system may comprise a dewatering system configured to concentrate compositions comprising carbonates, bicarbonates, or carbonates and bicarbonates. The treatment system may further comprise a filtration system, wherein the filtration system comprises at least one filtration unit configured for filtration of supernatant from the dewatering system, filtration of the composition from the processor, or a combination thereof. For example, in some embodiments, the filtration system comprises one or more filtration units selected from a microfiltration unit, an nltrafiltration >>nit., a nanofiltration unit, and a reverse osmosis unit. In some embodiments, the carbon dioxide processing system comprises a nanofiltrati.on unit configured to increase the concentration of divalent cations in the retentate and .r.educe the concentration of divalent cations in the retentate. In such embodiments, nanofiltration unit retentate may be recirculated to a processor of the system for producing compositions of the invention. As shown in Fig. 4, systems of the invention may be further configured to recirculate at least a porti.on of the supernatant from the treatment system.
[003011 Systems such as that shown in Fi.g, 3 may fiirther comprise a processor (I 10) comprising a contactor (112) (e.g., gas-liquid contactor, gas-liquid-solid contactor, etc.) and a reactor (114), wherein the processor is operably connected to each of a sotirce of M-containing gas (130), a sotirc of proton-removing agents (140), and a source of divalent cations (150). Such systems of the invention are con.figured for aqueous-based processing of carbon dioxide from the source of carbor dioxide using both the sottrce of proton-removing agents and the source of divalent cations, wherein the source of carbon dioxide comprises one or more additional components in addition to carbon dioxide. The contactor (112) may be operably connected to each of the source of carbon dioxide, (130) and the source of'proton-removin.g agents (140), and the contactor may be configured for charging an aqueous solution or slurry with carbon dioxide to produce a carbon dioxide-charged solution or slurry. In some embodiments, the contactor is configured to charge an aqueous solution with carbon dioxide to produce a substantially clear solution (i.e., substantially free of precipitation material, such as at least 95% or more free). As shown in. Fig. 3, the reactor (114) ma.v be oberably connected to the contactor (112) and the source of divalent cations (150), and the reactor may be configured to produce a composition of the invention. wherein the composition is a solution or shzrry comprising carbonates, bicarbonates, or carbonates and bicarbonates. In some embodiments, the reactor is configured to receive a substantially clear solution of carbonates, bicarbonates, or carbonates and bicarbonates from the processor and produce a composition comprising precipitation material (e.g., a slurry of carbonates, bicarbonates, or carbonates and bicarbop.ates of divalent cations). Systems such as the one shown. in Fig. 3 may optionally be operably connected to a treatment systetn, which treatment system niav comprise a liquid-solid separator (122) or some other dewatering system configured to treat processor-produced compositions to produce supernatant and concentrated compositions (e.g., concentrated with respect to carbonates and/or bicarbonates, and any other co-products resulting from process'tng, an industrial waste gas stream). The treatment system -92- Docket No. CLRA-026W0 may further comprise a filtration system, wherein the filtration system comprises at least one filtration unit configured for filtration of supematant from the dewatering system, filtration of the composition from the processor, or a combination thereof.
[00302] In sonie embodiments, the invention provides a system for processing carbon dioxide as shown in Fig. 4, wherein the system comprises a processor (110) and a treatment system (120) configured for an aqueous-based process for processing carbon dioxide fLom a source of carbon dioxide (130) using a source of proton-removing agents (140), wherein the source of carbon dioxide comprises one or more additional components in addition to carbon dioxide, and fizrther -uhereir_ the processor and the treatment system are operably connected for recirculating at least a portion of treatment system supernatant. The treatment system of such carbon dioxide-processing systems may com.prise a dewatering system and a filtration system. As such, the dewatering system, the filtration system, or a combination of the dewate. ing system and the filtration system may be configured to provide at least a portion o{'supernatant to the processor for processing carbon dioxide. Although not shown in Fig. 4, the treatment syst.em may also be con6gLzred to provide at least a portion of supernatant to a washing system configured to wash compositions of the ir_vention, wherein the compositions comprise precipitation material (e.g., Ca(703. MgCO~3, or combina*ions thereof), The processor of carbon dioxide-processing systems of the invention may be configured to receive treatment system supematant in a contactor (e.g., gas-liquid contactor, aas-liquid-soli(i contactor), a reactor, a combination of the contactor and the reactor, or in any other unit or combination of units in the processor. In some embodiments, the carbon dioxide-processing system is conf~gtjreci to provide at least a portion of the supernatant to a system or process external to the carbrn-dioxidP processing system. For example, a system of the invention may be operably connected to a desalination plant such that the system provides at least a portion of treatment system supernatant to the desalination plant for desalination.
[00303] In some embodiments, the invention provides a system for processing carbon dioxide as shown in Fig. 5, wherein the system comprises a processor (110) and a treatment system (120) configured for an aqueous-based process for processing carbon dioxide from a source of carbon dioxide (130) using a source of proton-removing agents (140), wherein the source of carbon dioxide comprises one or more additional components in addition to carbon dioxide, wherein the system fi;rther comprises an electrochemical system (160), and further wherein the processor, the treatment systetn, and t,he electrochemical system are operably connected for recirculating at least a portion of treatttient system supernatant, As described above in reference to the treatment system of Fig. 4, the dewatering system, the filtration system, or a corrbination of the dewatering system and the filtxation system may be configured to provide at lea.st a portion of treatment system supernatant to the processor for processina carbon dioxide. The treatment system may also be configured to provide at. least a portion of the treatment svstem supernatart to the electrochemical system, wherein the electrochemical system m.ay be configured to prod;.ace p.roton-re:moving agents or effect proton removal. As described in reference to Fig. 4, the treatment system may also be configtired to provide at least a portion of supematant to a washing system configured to wash composjtions of the invention, wherein the -~ 3- Docket No. CL,RA-026W0 compositions comprise precipitatiori material (e.g., CaCO3,, iYIgCO3, or combinations thereof). The processor of carbon dioxide-processing systems of the invention may be configured to receive treatment system supematant or an electrochemical systein streain in a contactor (e.g., gas-liquid contactor, gas-liquid-solid contactor), a reactor, a combination of the contactor and the reactor, or in any other unit or combination of units in the processor. In some emboditnents, the carbon dioxide-processing system may be configured to provide at least a portion of the supernatant to a system (e.g., desalination plant) or process (e.g., desalination) external to the carbon-dioxide processing system.
[00304] Recirculation of trea. ment system supernatt rt :'Ls advantaa;ous as recircul.ation provides efficient use of available resources; ininimal disturbance of surrotjnding environments; and t=educed energy requirements, which reduced energy requirements provide for lower (e. ;., small, neutral, or r.egati.ve) carbon footprints for systems and methods of the invention. When a carbon dioxide-processing system of the invention is operably connected to an industrial plant (e.g.. fossil fuel-fired rower plant such as coal-fired power plant) and utilizes power generated at the industrial plant, reduced energy requirements provided by recirculation of treatment system supernatant provide for a reduced parasitic load on the industrial plant. A carbon dioxide-processing system not configured for recirculation (i.e., a carbon--c'iox.idP processing system u-onfigured for a once-through process) such as that shown in Fig. 2, may have a parasitic load on the industrial plant of at least 10%
attributable to continuously pumping a fresh source of alkalinity (e.g., seawater, brine) into the system. In such an example, a 100 MW power plant (e.g.. a cc5a1-fired power plant) wou.td need to devote 10 MW of power to the carbon dioxide-processing system for continuously pizmpinf, a fre.sh source of alkalinity into the system. In contrast, a systetn configured for recirculation such as that shown in Fig. 4 or Fig. 5 may have a parasitic load on the i.ndustrial plant of less than 10%, wch as less than 8%, including less than 6%, for example, less than 4% or less than 2%, which parasitic load may be a+tributable to pzunping make-up water and recirculating supernatant. Carbon doxide-processin.g systPms configured for recirculation, may, when compared to systems designed for a once-through process, exhibit a reduction in parasitic load of at least 2%, such as at least 5%, including at least 10%. for example, at least 25% or at least 50%,. For example, if a carbon dioxide-processing system configured for recirculation consumes 9 MW of power for pumping make-up water and recirculating supernatant and a carbon dioxide-processing system.
designed. for a once-through process consumes 10 MW attributable to pumping, then the carbon dioxide-processing system configured for recirculation exhibits a 10% reduction in para.sitic lnad. For syste-nis sitch as those shown in Fis;s. 4 and 5 (i.e., carbon dioxide-processing systems coniaured for recirciaation). the re;ducticn in the parasitic load attributable to pumping and recirccilating may also provide a reduction in.
total parasitic load, especially when compared to carbon dioxide-processinv, systems conP;nired for once-through prccess. In some embodiments, recirculation provides a reduction in total parasitic loa.ca o.f. a carboa dioxide-processing system, wherein the reduction is at least 2%, such as at least 4%, including at least 6%, for example at least 8% or at least 10%
when compared to total parasitic load of a carbon dioxide==processint; system configured for once-through process. For example, if a carbon dioxide-processing system configured for recirculation has a 15% parasitic -04- Docket No. CLRA-026W0 load and a carbon dioxide-proces.,iz-,<, systein des.ignF,-d for a orice-thi-ough process has a 20% parasitic load, then the carbon dioxide-processing sy s+un configured for rec'rculat;_on exldbits a 5% reduction in total parasitic load. For example, a carbon dioxide-processing system corrfig4ired for recirculation, wherein recirculation comprises filtration through a filtration unit such as a.
nanofiltration imit (e.g., to concentrate divalent cations in the retentate and reduce divaleait cations in the penneate), inay have a reduction in total parasitic load of at least 2%, such as at least 4%, including at least 6%, for example at least 8% or at least 10% when compared to a carbon dioxide-processing system configured for once-through process.
[003051 Fig. 6B provides a schematic dia,7am of aCO.,-processint system according to an embodiment of the invention. As described herein, and nrcvided in Fio,zr<< 6B. systems of the tr:.vFntien may comprise a source of C02-containing gas (e.g., an indust.rial waste aas stream such as flue gas from a coal-fired power plant), a source of alkalinity (e.g., a source proto.n-reYmving agents), and a source of divalent cations. The source of C02-containing gas.. the source of alkalinity, and th.e source of divalent cations may each be operablv connected to a CO2 processor such as an absorber desc:=ibed herein, or, as shown in Fig. 6B, the source of C02-containing gas may be operably connected to a heat exchange (HX) dryer configured to dry precipitation material, which dryer, in turn, is operably connected to the CO2 processor.
The CO, processor may be configured for gas-liquid or gas-liquid-solid con*.a.cting ar.d comprise a Qas-liquid contactor, a gas-liquid-solid contactor, a reactor, a settling tank, or any combination thereof effectir,g absorption as described herein. The CO2 processor (e.g., absorber) may be configured to provide a composition (e.g., solution, slurrv, etc.) comprising carbonates, bicarbonates, or carbonates and bicarbonates to a treatment system of the invention, which, as shown in the embodiment provided. in Fig. 6B. comprises systems for dewatering, water treatment, chloride removal, drying, and lithification. The dewatering system may he configured to remove bulk water producing dewatered precipitation material, which., dependin; upon the source of divalent cations and/or the source of alkalinity, may comprise c!i'oride. Configured to use water provided by the water treatment system (e.g., one or more filtration units selected from the group of filtration.
units consisting of microfiltration, ultrafiltration, nanofiltration, reverse osmosis, forward ostr:osis filtration iulits), the chloride removal system may remove chloride, and depending upon the end prodtact, other salts from the precipitation material. The system as described in Fig. 6B may be further configured to nrovide precipitation material depleted in chloride to subsequent drying, in a SCM drying svstern to provide su.rnple.mentary cementitious material (SCM). Alternativelv, or in addition, the system may he configured to provide precipitation material depleted in chloride to a lithification system for nroduction oi'fi.n.e al;gregate coarse a;;r;renate. Fig. 6B also shows that the system is configured to provide clean exhauct C02-depleted waste ps stream comprising mostly N2), fresh water (e.g.., potable water), brine (e.g., N,:C'?(aq)i, and a concentrated source of divalent cations, which comprises divalent cations left over from C0., n~ oc;essira.
[003061 Fig. 6C provides a more detailed representation of a CO2 processor of the invention. For example, in some embodiments, Fig. 6C provi.des a more detailed representation of the CO.-processor of Fig. 6B. COZ
processors of the invention such as that shown in Fig. 6B ma.v comprise an induced drafl fan (ID fan) -)5- Docket No. CLRA-026W0 configured to provide an industrial source of COZ flue gas) to an absorber.
The absorber may further comprise surge tanks for the source of divalent cations and/or the source of alkalinity (e.g., source of proton-removing agents). Regarding the source of divalent cations, for example, the source of divalent cations may be operably connected to a surge tank configured to rel;nalate potentially discontinuous flow (e.g., a surge in flow), which surge tank may be operably connected to a feed pump configured to pump the source of divalent cations to an absorber. As shown in Fig. 6C, the CO2 processor miay further comprise a recirculation pump configured to recirculate solution or slurry from the bottom of the absorber to one or more upper stages of the absorber. Solution or sbarrv that is not recirculated iiiay be provided to a product surge tank, which, in conjunction with the operably connected product pump, is configurecl to provide a regulated flow of product to a dewatering system of the invention. T'ne systeni may be furtber configured to cease recirculation, divert all absorber solution of slurry to the product surge tank, 2,r.nd wash the absorber with wash water. As with the source of divalent cations anc'. the sot-ce of alkalinity (e.,r., source of protor-removing agents), the wash water may be provided to the absorbff frotn P. tank containing the wa~h. water through the intermediacy of a pump=
[00307] Fig. 7 provides a schematic of a s,ystenl accerdinf; to one embodimert of the invention. In Fig. 7, system 100 includes water source 110. lp, certain embodiments, water source 110 includes a structure having an input for water (e.g., alkaline earth metal ion-containing Nvater), such as a pipe or conduit from an ocean, etc. Where the water source that is processed by the syste.m to produce the precipitate is seawater, the input is in fluid communication with a source of sea water, e.g., such as where the inpu.t is a pipe line or feed from ocean water to a land based system or a inlet port in the hull of ship, e. ¾., where the system is part of a ship, e.g., in an ocean based system.

[00308] Also shown in Fig. 7, is CO, source 130. This system also includes a pipe., duct, or cond.uit, which directs CO2 to system 100. The gaseous waste stream employed in methods of the invention may be provided from the industrial plant to the site of precipitation in any convenient manner that conveys the gaseous waste stream from the industrial plant to the precipitation plant. In certain embodimen.ts, the waste stream is provided with a gas conveyer, e.g., a duct, which ruris from a site of the industrial plant, e.g., a flue of the industrial plant, to one or more locations of the precipitation site. The source of the l;aseous waste stream may be a distal location relative to the site of precipitation, such that the source of the gaseous waste stream is a location that is 1 mile or more, such as 10 nules or more, including 100 miles or more, from the precipitation location. For example, the gaseous waste stream may have been transported to the site of precipitation from a remote industrial plant via a CO., gas conveyance system, e.g., a pipeline. The industrial plant generated COZ containing gas may or may not be pro~.essedõ e.g., remove other components, etc., before it reaches the precipitation site (i.e., a carbonate cornpound precirita.ti-n p2ant). In yet other instances, source of the gaseous waste stream is proximal to the preci.p:it. tion sitc,, m;hcre such i.nstaaces may include instances where the precipitation site is integra.ted with the source of the gaseous waste strea,n., such as a power plant that integrates a carbonate compound precipitatiori reactor.

"96' Docket No. CLRA-026WO

[00309] Where desired, a portion of but less than the entire gaseous waste stream from the industrial plant may be employed in precipitation reaction. In these embodiments, the portion of the gaseous waste stream that is employed in precipitation may be 75% or less, such as 60% or less and including 50% and less. In yet other embodiments, substantially the entire gaseous waste stream produced by the industrial plant, e.g., substantially all of the flue gas produced by the industrial plant, is employed in precipitation. In these embodiments, 80% or more, such as 90% or more, including 95% or more, up to 100% of the gaseous waste stream (e.g., flue gas) generated by the source may be employed during precipitation.
[00310] As indicated above, the gaseous waste stream may be one that is obtained from a flue or analogous structure of an industrial plant. In these embodiments, a line, e.g., duct, is connected to the flue so that gas leaves the flue through the line and is conveyed to the appropriate location(s) of a precipitation system (described in greater detail below). Depending on the particular configuration of the portion of the precipitation system at which the gaseous waste stream is employed, the location of the source from which the gaseous waste stream is obtained may vary, e.g., to provide a waste stream that has the appropriate or desired temperature. As such, in certain embodiments where a gaseous waste stream having a temperature ranging for 0 C to 1800 C, such as 60 C to 700 C is desired, the flue gas may be obtained at the exit point of the boiler or gas turbine, the kiln, or at any point through the power plant or stack, that provides the desired temperature. Where desired, the flue gas is maintained at a temperature above the dew point, e.g., 125 C, in order to avoid condensation and related complications. Where such is not possible, steps may be taken to reduce the adverse impact of condensation, e.g., employing ducting that is stainless steel, fluorocarbon (such as poly(tetrafluoroethylene)) lined, diluted with water and pH controlled, etc., so the duct does not rapidly deteriorate.
[00311] To provide for efficiencies, the industrial plant that generates the gaseous waste stream may be co-located with the precipitation system. By "co-located" is meant that the distances between the industrial plant and precipitation system range from 10 to 500 yards, such as 25 to 400 yards, including 30 to 350 yards.
Where desired, the precipitation and industrial plants may be configured relative to each other to minimize temperature loss and avoid condensation, as well as minimize ducting costs, e.g., where the precipitation plant is located within 40 yards of the industrial plant.
[00312] Also of interest in certain embodiments is a fully integrated plant that includes an industrial function (such as power generation, cement production, etc.) and a precipitation system of the invention. In such integrated plants, conventional industrial plants and precipitation system, such as described below, are modified to provide for the desired integrated plant. Modifications include, but are not limited to:
coordination of stacks, pumping, controls, instrumentation, monitoring, use of plant energy, e.g., steam turbine energy to run portions of the precipitation component, e.g., mechanical press, pumps, compressors, use of heat from cement and/or power plant obtained from steam or heat from air to air heat exchanger, etc.
[00313] In certain embodiments, the C02-containing gaseous stream may be pretreated or preprocessed (e.g., treated with H202) prior to contacting it with water, e.g., alkaline earth metal-containing water (e.g., in a -97- Docket No. CLRA-026W0 charging reactor). Illustrative pretreatment or preprocessing steps may include: temperature modulation (e.g., heating or cooling), decompression, compression, incorporation of additional components (e.g., hydrate promoter gases), oxidation of various components to convert them to forms more amenable to sequestration in a stable form, and the like. In certain embodiments, pretreatment of the gaseous waste stream improves the absorption of components of the C02-containing gaseous stream into water, e.g., alkaline earth metal-containing water. An exemplary pretreatment for improving absorption includes subjecting the C02-containing gaseous stream to oxidizing conditions.
[00314] The water source 110 of Fig. 7 and the CO7 gaseous stream source 130 are connected to a CO2 charger in precipitation reactor 120. The precipitation reactor 120 may include any of a number of different design features, such as temperature regulators (e.g., configured to heat the water to a desired temperature), chemical additive components, e.g., for introducing chemical pH elevating agents (such as hydroxides, metal oxides, or fly ash) into the water, electrochemical components, e.g., cathodes/anodes, mechanical agitation and physical stirring mechanisms and components to re-circulate industrial plant flue gas through the precipitation plant. Precipitation reactor 120 may also contain design features that allow for the monitoring of one or more parameters such as internal reactor pressure, pH, precipitate particle size, metal-ion concentration, conductivity and alkalinity of the aqueous solution, and pCO2.
This reactor 120 may operate as a batch process or a continuous process.
[00315] In some embodiments, the contacting apparatus (e.g. gas-liquid or gas-liquid-solid contactor) is apart of a system. In such a system, the absorbing solution after contacting the gas is sent to a processing station. In some embodiments, the absorbing solution after contacting the gas and any products of the contact of the absorbing solution with the gas, is passed to other systems (i.e. a processing station), including but not limited to, a precipitating tank, dewatering systems, and building fabrication system.
In some embodiments, the contacting mixture after contacting the gas, comprising a liquid component, any products of the contact of the contacting mixture with the gas, and a optionally a solid component that is not a precipitate, is passed to other systems including, but not limited to, a precipitating tank, dewatering systems, and building fabrication system. In some embodiments, the slurry after contacting the gas, comprising a liquid component, a solid component, and any products of the contact of the slurry with the gas, is passed to other systems including, but not limited to, a precipitating tank, dewatering systems, and building fabrication system. In some embodiments, the solid component (if any) of the absorbing solution. and the products of contacting the absorbing solution with the gas are separated from the absorbing solution that has been contacted with the gas. In some embodiments, the solid component (if any) of the contacting mixture and the products of contacting the contacting mixture with the gas are separated from the contacting mixture that has been contacted with the gas. In some embodiments, the solid component (if any) of the slurry and the products of contacting the slurry with the gas are separated from the slurry that has been contacted with the gas. In some embodiments, the separation of solids from the absorbing solution, contacting mixture, or slurry that has contacted the gas is accomplished by a sieve, a. press, a centrifuge, a spray dryer, an air assisted method, a -9$- Docket No. CLRA-026W0 heated method of dewatering or any combination thereof. In some embodiments, the effluent liquid remaining after separation of the solids from the absorbing solution, contacting mixture, or slurry that has contacted the gas is treated by a system that includes, but is not limited to, nanofiltration, reverse-osmosis, chemical recovery, desalination, adjustment in solution chemistry for recirculation, pH adjustment for release or any combination thereof. In some embodiments, the solids separated from the absorbing solution, contacting mixture, or slurry that has contacted the gas is passed to a building materials producing system. In some embodiments, the apparatus is a portable apparatus that is contained within a shipping container such that it is capable of being transported via rail (train), waterways (barge), road (truck), or any combination thereof to any desired location. In some embodiments, the portable apparatus is apart of a system. In some embodiments, the entire system is a portable system that is contained within one or more shipping containers that are capable of being tran.sported via rail (train), wate.rways (barge), road (truck), or any combination thereof to any desired location.
[00316] At times, to affect the amount of incorporation of a component of a gas into a liquid or slurry, the gas needs to be contacted with a liquid or slurry for more time than is possible with one pass through an apparatus of the invention. In some embodiments, the gas is recirculated to affect the amount of incorporation of a component of a component of a gas into a liquid or sluny. Multiple apparatus may be used to effect the incorporation of a component of a gas into a liquid or slurry, such that the gas is passed from one apparatus to one or more subsequent apparatus. The subsequent apparatus may utilize different: liquid or slurries;
structural features inside the column, chamber, or reactor of the apparatus;
droplet producing systems or apparatus; or have a differeiit overall orientation from the first apparatus.
In some embodiments, the system of the invention includes an array of the apparatus of the invention. Ln such embodiments, the array may include apparatus through which the gas passes serially, one apparatus after the other, or the array may include apparatus through which the gas passes simultaneously, such that the apparatus are used in parallel. In some embodiments, the array includes rows of multiple apparatus. In some embodiments, the gas enters the first apparatus of the rows of multiple apparatus simultaneously, then flows into th.e subsequent apparatus, such that effectively the series of apparatus are working in parallel.
[00317] In some embodiments, systems of the invention seek to optimize the horsepower needed to accomplish the absorption and the physical footprint of the apparatus. In such embodiments, the system comprises at least two apparatus of the invention for contacting a mixture (e.g. a slurry or contacting liquid) with a gas to remove one or more component gas (e.g. C02, SOx). The first apparatu.s is oriented such that its long axis is horizontal and such that it is placed low to the ground. The purpose of this orientation is that this portion of the absorber will have a low liquid head requirement, thus niaking it easier to pump the contacting mixture (i.e. absorbing solution) to the top of the contacting chamber of the apparatus, i.e. require less energy.
The contacting mixture in the horizontal portion of the apparatus may be different along the length of that portion, or it may be the same mixture. The contacting mixture in the horizontal portion of the apparatus may be clear solution or a slurry, and it may or may not be recirculated. The flow of the inlet gas and the flow of -99- Docket No. CLRA-026W0 the contacting mixture may be co-current or counter current, or the flow of the gas and solution may vary in stages within the horizontal length of the apparatus. The contacting mixture in the horizontally oriented apparatus may be recirculated within the apparatus to in effect cause countercurrent flow of the contacting mixture with respect to the flow of the inlet gas. T'he second apparatus in system is oriented vertically, such that the length of it is perpendicular to the ground. The vertically oriented apparatus could be staged (is more often than not staged) and the contacting mixture flow could be cocurrent or countercurrent to the flow of the inlet gas. The vertical section of the absorber would have a demister prior to the gas outlet. This section could also recirculate the contacting mixture either to various stages within the vertically oriented apparatus or to the horizontally oriented apparatus. The contacting mixture could also be in some of the lower stages either clear solution or slurry. The slurry includes a solid component that may be a mineral, an industrial waste (e.g. fly ash, cement kiln dust), and/or solid precipitate from the process in the case where recirculation is employed. Comminution may be apart of the recirculation system, if the contacting mixture includes slurry.
The clear solution or liquid component of the slurry may be seawater, a naturally occtirring alkaline brine, an industrial waste brine, a desalination effluent brine, a synthetic brine, freshwater, a solution augmented with additional divalent cations, a solution a.ugmented with additional alkalinity, or a combination thereof.
[00318] Fig. 26 is a schematic of an embodiment of the invention in which the system comprises two apparatus, one horizontallv oriented, low to the ground, and the second apparatus, vertically oriented. The configuration shown in Fig. 26 (and simi.larly, Figs. 27 and 28) minimizes both the horsepower requirement and the physical footprint requirements of the system. The lower, hori.zontally oriented apparatus requires less liquid pressure head, and thus less horsepower to operate. The taller, vertically oriented apparatus requires less area for its physical footprint. The solution in the vertically oriented apparatus may be recirculated to the horizontally oriented apparatus, recirculated solely within the vertically oriented apparatus, recirculated partially within the vert ically oriented apparatus and partially within the horizontally oriented apparatus, or not recirculated. The vertically oriented appa-ratus may have a demisting section just prior to the gas outlet with accepts clear liquid (i.e. without solid particulates) as its intake. The vertically oriented apparatus may accept clear liquid or a sltirry as its intake for the main portion of the apparatus, shown as three sprays in the figure. The system that includes the two apparatus may be a portable system, such that the system is contained in a shipping container that may be shipped via rail, waterways andlor road.
[00319] Fig. 27 is a schematic of an embodiment of the invention, similar to that shown in Fig. 26 in that the system comprises two apparatus, one horizontally oriented, low to the ground, and the second apparatus, vertically oriented. In the embodiment shown in Fig. 27, the flow of the gas in the first apparatus (that which is horizontally oriented, low to the ground) is forced to follow a convoluted path. The nature of the path that the gas follows creates areas of countercurrent and cocurrent contact between the gas and the solution in the first (i.e., lower) apparatus. As in Fig. 26, the solution in the vertically oriented apparatus may be recirculated to the horizontally oriented apparatus, recirculated solely within the vertically oriented apparatus, recirculated partially within the vertically orien.ted apparatus and partially within the horizontally oriented apparatus, or -100- Docket No. CLRA-026W0 not recirculated. T'he vertically oriented apparatus may have a dernisting section just prior to the gas outlet with accepts clear liquid (i.e. without solid particulates) as its intake. The vcrticalty oriented apparatus may accept clear liquid or a slurry as its intake for the inain portion of the apparatus, shown as three sprays in the figure. The system that includes the two apparatus may be a portable system, such that the system is contained in a shipping container that may be shipped via rail, waterways and/or road.
[00320] Fig. 28 is a schematic of an embodiment of the invention, similar to those shown in Figs. 26 and 27 in that the system comprises two apparatus, one horizontally oriented, low to the ground, and the second apparatus, vertically oriented. In the embodiment shown in Fig. 28, the solution (e.g. absorbing solution, contacting mixture) in the horizontally oriented apparatus is recirculated within that apparatus such that solution enters the apparatus initially at the point in the apparatus ffirthest away from the gas inlet. The solution is then recirculated using pL~mps closer to the gas inlet area. This recirculation in effect creates a countercurrent flow between the overall fluid flow ard ~a.s flow in the apparatus, though the construction of -the apparatus may convolute the flow of the gas so tt,_a relative to the solution falling from the sprays, the gas is locally flowing alternately cocurrently and countercurrently. As in Figs.
26 and 27, the solution in the vertically oriented apparatus mav be recirculated to the horizontally oriented apparatus, recirculated solely within the verticallv oriented apparatus, recirculated portially within the ve.rtically oriented apparatus and partially within the horizontally oriented apparatus. or not recirculated. The vertically oriented apparatus may have a demisting section just prior to the gas outlet with accents clear liquid (i.e. without solid particulates) as its intake. The vertically oriented apnaratus may accept clear liqui.d or a slurry as its intake for the main portion of the apparatus, shown as three sprays in the figure. The system that includes the two apparatus may be a portable system, such that the system is contained in a shipping container that may be shipped via rail, waterways and/or road.
[00321] Fig. 29 is a schematic of an embodiment of the invention in which different types of apparatus are used in series. The apparatus are ones that employ arrays of sprays or sprays and shed rows combined. The apparatus also have fluid (i.e. absorbing solution or contacting mixture) flovving cocurrent and countercurrent with respect to the gas flow. The fluid (i.e. absorbing solution or contacting mixture) in each apparatus may be the same or different, and it maybe recirculated within each apparatus or from one apparatus to another to cause the desired gas incorporation (i.e. absorption), aid in some cases, precipitation.
[00322] Figs. 30 and 31 are schematics of embodiments of the invention showing systems of the invention in which apparatus are arranged in rows and the gas flows into the apparatus both in parallel and in series. Fig.
30 shows a configuration where the Qas flows into more than one apparatus, and in these first apparatus, the gas and liquid (e.g. absorbing solution, contacting mixture) flows are cocurrent, then the gas flows into more than one subsequent appara_tus where the flows are counterctirrent. Fig. 31 shows a configuration where gas flows into more than one apparatus, where in the first of the multiple apparatus, the gas and liquid flows are countercurrent, then in the subsequent multiple apparatus, the flows are cocurrent. In each apparatus, the -101- Docket No. CLRA-026W0 solution or contacting mixture may be recirculated within the apparatus or from one apparatus to another to obtain the desired removal of a component of the gas (e.g. C02, SOx) or precipitate.
[00323] Precipitation reactor 120, further includes an output conveyance for mother liquor. In some embodiments, the output conveyance may be configured to transport the mother liquor to a tailings pond for disposal or in a naturally occurring body of water, e.g., ocean, sea, lake, or river. In other embodiments, the systems may be configured to allow for the mother liquor to be employed as a coolant for an industrial plant by a line running between the precipitation system and the industrial plant.
In certain embodiments, the precipitation plant may be co-located with a desalination plant, such that output water from the precipitation plant is employed as input water for the desalination plant. The systems may include a conveyance (i.e., duct) where the output water (e.g., mother liquor) may be directly pumped into the desalination plant.
[00324] Fig. 32 shows a piping and instrument diagram for an embodiment of the invention. The diagram shows two possible flue gas sources coming from a power plant. The flue gas is shown entering the bottom of a contacting chamber (i.e. the item labeled absorber). The contacting chamber has at the bottom an exit conduit as well as a connection to a recirculation system, including pumps and switching valves. In the center of the contacting chamber are sprays, and at the top of the chamber is a demisting section (i.e. mist eliminator) before the gas outlet. Shown is a source of spray water for the demister section that is separate from the source of water for the center section. of the chamber. The source of solution for the center of the chamber also has connections to at least one source of sodium hydroxide (e.g.
an electrochemical process, alkaline brine). A slurry mill is also showrt in Fig. 32. This mill may be a location for comminution of the solid component of a slurry, in which the solid component may be precipitate material, mineral or industrial waste (e.g. fly ash, cement kiln dust). In some embodiments, the contacting chamber, or absorber, shown in Fig. 32 may be portable, such that it fits within a standard shipping container and may be shipped via train, barge and/or truck to any facility where desired.
[00325] The system illustrated in Fig. 7 further includes a liquid-solid separation apparatus 140 for separating a precipitated carbonate mineral composition from the precipitation system effluent. The liquid-solid separation apparatus may achieve separation of a precipitation product from precipitation system effluent by draining (e.g., gravitational sedimentation of the precipitation product followed by draining), decanting, filtering (e.g., gravity filtration, vacuum filtration, filtration using forced air), centrifuging, pressing, or any combination thereof. In som.e embodiments, the liquid-solid separation apparatus comprises a baffle, against which precipitation station effluent is flowed to effect precipitation product and supernatant separation. In such embodiments, the liquid-solid separation apparatus may further comprise a collector for collecting precipitation product. A source of liquid-solid separators useful in some embodiments is Epuramat's Extrem-Separator ("ExSep") liquid-solid separator, or a modification thereof. In some embodiments, the liquid-solid separation apparatus comprises a spiral charnel, into which precipitation station effluent is flowed to effect precipitation product and supernatant separation. In such embodiments, the liquid-solid separation apparatus may further comprise an array of spiral channel outlets for c,ollecting, precibitation product. A source of -102- Docket No. CLRA-026W0 liquid-solid separators usefixl in some embodiments is Xerox PARC's spiral concentrator, or a modification thereof. At least one liquid-solid separation apparatus is operably connec-ted to the precipitation station such that precipitation station effluent may flow froin the precipitation station to the liquid-solid separation apparatus (e.g., liquid-solid separation apparatus comprising either a baffle or a spiral channel). As detailed above, any of a number of different liquid-solid apparatus rnay be used in combination, in any arrangement (e.g., parallel, series, or combinations thereof), and the precipitation station effluent may flow directly to the liquid-solid separation apparatus, or the effluent may be pre-treated.
[00326] The system also includes a washing station, 150, where bulk dewatered precipitate from separation station, 140 is washed, e.g., to remove salts and other solutes from the precipitate, prior to drying at the drying station.
[00327] The system fiarther includes a drying station 160 for drying the precipitated carbonate mineral composition produced by the carbonate mineral precipitation station. Depending on the particular drying protocol of the system, the drying station may incLaee a filtration element, freeze drying structure, spray drying structure, etc as described more fully above. The system may include a conveyer, e.g., duct, from the industrial plant that is connected to the dryer so that a gaseous waste stream (i.e., in.dustrial plant flue gas) may be contacted directly with the wet precipitate in the drying stage.
1003281 The dried precipitate may undergo further processing, e.g., grinding, milling, in refining station, 180, in order to obtain desired physical properties. One or more components may be added to the precipitate where the precipitate is used as a building material.
[00329] The system further includes outlet conveyerr;, e.g., conveyer belt, slurry pump, that allow for the removal of precipitate from one or more of the following: the reactor, drying station, washing station or from the refining station. The product of the precipitation reaction may be disposed of in a number of different ways. The precipitate may be transported to a long term storage site in empty conveyance vehicles, e.g., barges, train cars, trucks, etc., that may include both above ground and underground storage facilities. In other embodiments, the precipitate may be disposed of in an underwater location. Any convenient protocol for transporting the composition to the site of disposal may be employed. In certain embodiments, a pipeline or analogous slurry conveyance structure may be empl_oyed, where these approaches may include active pumping, gravitational mediated flow, etc.
[00330] In certain embodiments, the system will fiirther include a station for preparing a building material, such as cement, from the precipitate. This station can be configured to produce a variety of cements, aggregates, or cementitious materials from the precipitate, e.g., as described in co-pending U.S. Patent Application Publication No. 2009/0020044, pub'ished 25 November 2008, which is incorporated herein by reference in its entirety.
[00331] As indicated above, the system may be present on land or sea. For example, the system may be a land based system that is in a coastal region, e.g., close to a source of seawater, or even an interior location, where water is piped into the system from a salt water source, e.g., ocean.
Alternatively, the system may be a water--1 03- Docket No. CLRA-026WO

based system, i.e., a system that is present on or in water. Such a system may be present on a boat, ocean based platform etc., as desired. In certain embodiments, the system may be co-located with an industrial plant at any convenient location. The precipitation plant may be a land-based plant that is co-located with the land-based industrial plant, e.g., in a coastal region, such as close to a source of water (e.g., seawater). Also of interest are interior locations, where water is piped into the system directly from a water source (e.g., an industrial plant, a distal lake, a distal ocean). Alternatively, the precipitation plant may be present on water, e.g., on a barge, boat, ocean based platform etc., as desired, for example where real-estate next to a industrial plant is scarce. In certain embodiments, the precipitation plant may be a mobile plant, such that it is readily co-located with an industrial plan.t.
[00332] Systems of the invention that are co-located with an industrial plant, such as a power plant, may be configured to allow for synchronizing the activities of the industrial. plant and precipitation plant. In certain instances, the activity of one plant may not be match e.d to the activity of the other. For example, the precipitation plant may need to reduce or stop its acceptance of the gaseous waste stream but the industrial plant may need to keep operating. Conversely, situations may arise where the industrial plant reduces or ceases operation and the precipitation plant does not. To address situati.on.s where either the precipitation plant or industrial plant may need to reduce or stop its activities, design features that provide for continued operation of one of the co-located plants while the other reduces or ceases operation may be employed, as described in detail above. For example, the systems of the invention may include in certain embodiments, blowers, fans, and/or compressors at various points alcng the connecting line between. the industrial plant and the precipitation plant in order to control the occurrence of backpressure in the ducts that connect the industrial plant to the precipitation plant. In certain embodiments, a gas storage facility may be present between the industrial plant and the precipitation plant, Where desired, the precipitation plant may include emissions monitors to evaluate any gaseous emissions produced by the precipitation plant as required by Air Quality Agencies.
[00333] Aspects of the invention include the use of a CO2 containing industrial plant gaseous waste stream, e.g., an industrial plant flue gas, at one or more stages of a process in which a storage-stable COz containing product is precipitated. As such, the CO ! containing industrial plant gaseous waste stream is employed in a precipitation process. In embodiments of the invention, the gaseous waste stream is employed at one or more steps of the precipitation process, such as in a precipitation step, e.g..
where it is emploved to charge water with C02, or during a precipitate drying step, e.g., where precipitated carbonate compound is dried, etc.
[00334] Where desired, the flue gas from the industrial plant can be re-circulated through the precipitation plant until total adsorption of the remnant. CO? approaches 100%. or a point of diminishing returns is achieved such that the remaining flue gas can be processe.d using alternative protocols and/or released into the atmosphere.
[00335] In some embodiments, the apparatus and systems of the invention my be operably connected to a power plant that produces nower and an industrial waste gas (i.e. flue gas).
In such embodiments, the -J 04- Docket No. CLRA-026W0 apparatus and systems of the invention may be considered an emissions control system that removes certain constituents from the industrial waste gas. In some embodiments, the industrial waste gas comprises carbon dioxide, SOx, NOx, heavy metals, non-CO2 acid gas, and fly ash. In some etnbodiments, the apparatus and systems of the invention may act as an emissions control system that is configured to remove carbon dioxide from an industrial waste gas. In some embodiments, the apparatus and systems of the invention may act as an emission control system that i s configured to remove at least carbon dioxide from an industrial waste gas and additionally remove SOx from the industrial waste gas. In some embodiments, carbon dioxide and optionally SOx are removed by an emissions control system c.omprising apparatus and/or systems of the invention, while utilizing an minimized a-nount of the power produced by the power plant, such as less than 30% of the power produced by the power plant. In some embodiments, the emissions control systera of the invention may achieve utilizing less than 30% of the power produced by the power plant by employing or accepting an alkaline solution from an electrochemical svstem conf ,ured to produce a caustic solution, particularly of the type of the low-voltage electrochemical system described further herein. In some embodiments, the emissions control system of the invention is connected to a. power plant and configured to absorb at least 50%
of the carbon dioxide from the waste gas and use less than 30% of the energy generated by the power plant. In some embodiments, the emissions control system of the invention is connected to a power plant and configured to absorb at least 90% of the oxides of sulfiir (SOx) from the waste gas and use less than 30% of the energy generated bv the power plant. In some embodiments, the emissions control system of the invention is connected to a power plant and configured to absorb at least 50% of the carbon dioxide and at least 80% of the sulfur oxide (SOx) from the waste gas and use less than 30% of the energy generated by the power plant.
In some embodiments, the apparatus and systems of the invention may be used in conjunction with existing emissions control system in place at a plant that combU.sts fossil fuel. In some embodiments, the existing emissions control system may include or utilize: an electrostatic precipitator to coll.ect particulates, SOx control technology, NOx control technology, physical filtering technology to collect particulates, mercury control technology, among other control measures.
[003361 As reviewed above, precipitation systems of the invention may be co-located with an industrial plant.
An example of such a system is illustrated in Fig. 7. In Fig. 7, flue gas outlet 170 from power plant 200 is used in both the precipitation reactor 1.20 as the source Qf COz 130 and the dryer 160 and the source of heat.
Where desired, backpressure controls are employed to at least reduce, if not eliminate, the occurrence of backpressure which could arise from directing a portion of, if not all of, the industrial plant gaseous waste stream to the precipitation plant 100. An.y convenient manner of controlling backpressure occurrence may be employed. In certain embodiments, blowers, fans, and/or compressors are provided at some point along the connecting line between the industrial plant and precipitation plant. Tn certain embodiments, the blowers are installed to pull the flue gas into ducts that pozt the flue gas to the precipitati.on plant. The blowers employed in these embodiments may be electrically or meehanically dri.ven blowers. In these embodiments, if present at all, backpressure is reduced to a level of 5 inches or less, siach as one inch or less. In certain embodiments, a -105- Docket No. CLRA-026W0 gas storage facility may be present between the industrial plant and the precipitation plant. When present, the gas storage facility may be employed as a surge, shutdown and smoothing systern so that there is an even flow of flue gases to the precipitation plant.
[00337] Aspects of the invention include synchronizing the activities of the industrial plant and precipitation plant. In certain instances, the activity of one plant niay not be matched to the activity of the other. For example, the precipitation plant may need to reduce or stop its acceptance of the gaseous waste stream but the industrial plant may need to keep operating. Conversely, situations may arise where the industrial plant reduces or ceases operation and yet the precipitatien plant does not. To address such situations, the plants may be configured to provide for continued operation of one of the co-?_ocated plants while the other reduces or ceases operation may be employed. For example, to address the situation where the precipitation plant has to reduce or eliminate the amount of gaseous waste strea.m it accepts from the industrial plant, the system may be configured so that the blowers and ducts conveying waste stream to the precipitation plant shut off in a controlled sequence to minimize pressure swings and the industrial plant flue acts as a bypass stack for discharge of the gaseous waste stream. Similarly, if the industrial plant reduces or eliminates its production of gaseous waste stream, e.g., the indus*rial plar.t is dispatched whollv or partially down, or there is curtailment of industrial plant output under some pre-agreed level the system may be conflgured to allow the precipitation plant to continue operation, e.g.., by providing an alternate source of CO,, by providing for alternate heating protocols in the dryer., etc.
[00338] Where desired, the precipitation plant may inchide emissions monitors to evaluate any gaseous emissions produced by the precipitation plant and to make required reports to regulatory agencies, both electronic (typically every 15 minutes), daily, weekly, monthly, quarterly, and. annually. In certain embodiments, gaseous handling at the precipitation plant is sufficiently closed that exhaust air from the precipitation plant which contains essentialiv all of the unused flue gas from the ind~.~.strial plant is directed to a. stack so that required Continuous Emissions Monitoring Systems can be installed in accordance with the statutory and regulatory requirements of the Country, province, state city or other political jurisdiction.
[00339] In certain embodiments, the gaseous waste stream generated by the industrial plant and conveyed to the precipitation plant has been treated as required by A'r Quality Agencies, so the flue gas delivered to the precipitation plan already meets Air Quality requirements. In these embodiments, the precipitation plant may or may not have alternative treatment systems in place in the event of a shutdow*i of the precipitation plant.
However, if the flue gas delivered to has been only c~artially treated or not treated at all, the precipitation plant may include air pollution control devices to meet regulatory requirements, or seek regulatory authority to emit partially-treated flue gas for short periods of time. In yet other embodiments, the flue gas is delivered to precipitation plant for all processing. In such embodiments, the syst.ern may include a safeguard for the situation where the precipitation plant cannot accept th , waste stream, e.g., by ensuring that the pollution controls installed in the industrial plar.t t.urn on and. cor.trol emissions as required by the Air Quality Agencies.

-106- Docket No. CLRA-026W0 [00340] The precipitation plant that is co-located with the industrial plant may be present at any convenient location, be that on land or water. For example, the precipitation plant may be a land-based plant that is co-located with the land-based industrial plant, e.g., in a coastal region, such as close to a source of sea water.
Also of interest are interior locations, where water is piped into the system directly from a water source (e.g., an industrial plant, a distal lake, a distal ocean). Alternatively, the precipitation plant may be present on water, e.g., on a barge, boat, ocean based platform etc., as desired, for example where real-estate next to a industrial plant is scarce. In certain embodiments, the precipitation plant may be a mobile plant, such that it is readily co-located with a industrial pl.ant, [00341] As indicated above, of interest in certain embodiments are waste streams produced by integrated gasification combined cycle (IGCC) plants. In these types of plants, the initial fuel, e.g., coal, biomass, etc., is first subjected to a gasification process to produce syngas., which may be shifted, generating amounts of C02, CO and H2. The product of the gasification protoõol may be conveyed to the precipitation plant to first remove C02, with the resultant COZ scrubbed product bein.g returned to a power plant for use as fuel. In such embodiments, a line from the gasification unit of a power plant may be present between a power plant and precipitation plant, and a second return line may be present between the precipitation plant and a power plant to convey scrubbed syngas back to a power plant.
[00342] In certain embodiments, the co-located industrial plant and precipitation plant (or integrated plant) is operated with additional CO2 emission reduction approaches. For example, m.aterial handling, vehicles and earthmoving equipment, locomotives, may be configured to use biofuels in lieu of fossil fuels. In such embodiments, the site may include fizel tanks to store the biofuels.
[00343] In addition to sequestering CO2, embodiments of the invention also sequester other components of industrial plant generated gaseous waste streams. For example, embodiments of the invention results in sequestration of at least a portion of one or more of NOx, SOx, VOC, Mercury and particulates that may be present in the waste stream, snch that one or more of these nroducts are fixed in the solid precipitate product.
[003441 In Fig. 7, precipitation system 100 is co-located with industrial plant 200. However, precipitation system 100 is not integrated with the industrial plant 200. Of fizrther interest in certain embodiments therefore is an integrated facility, which, in addition to an industrial plant, includes power generation, water treatment (seawater desalinization or mineral rich freshwater treatment) and precipitation components' as described in U.S. Patent Application Publication No. 2009/0001020, published l January 2009, which is incorporated herein by reference in its entirety. The water source for the precipitation plant may be derived from the waste streams of the water treatment plant. The resultant mother liquor from the carbonate precipitation plant may be used as the feedstock for the water treatment plant. The resultant integrated facility essentially uses fuel, minerals and untreated water as inputs, and outputs energy, a processed industrial product, e.g., cement, clean water, clean air and carbon-sequestering building materials.
[00345] Fig. 33 provides an example of where a precipitation system 100 is integrated with an industrial plant, in this case a coal fired powei- plant 100. In. power plant 300, coal 310 fuels stsam boiler 315 to produce l 0", - Docket No. CLRA-026W0 steam, which, in turn, runs a turbine (not shown) to produce power. Steam boiler 315 also produces bottom ash or boiler slag 325 and flue gas 320. Flue gas 320 contains fly ash, C02, and sulfates. Flue gas 320 and bottom ash 325 are combined with water from water source 330 in reactor 340 and subjected to precipitation reactions, as described above. Pump 350 facilitates transport of precipitated product from reactor 340 to spray dryer 360, which employs flue gas 320 to spray dry the precipitated product for subsequent disposal, e.g., by placement in a landfill or use in a building product. Treated flue gas 370 exits spray dryer 360 and is then discharged to the atmosphere in stack 380. Treated flue gas 370 is gas in which the fly ash, sulfur, and CO2 content has been substantially reduced, if not completely removed, as cornpared to flue gas 320. As an example of the system shown in Fig. 33, the CO2 source may be flue gas from coal or other fuel combustion, which is contacted with the volunie of saltwater with little or no pretreatment of the flue gas. In these embodiments, the use of fiiels such as high-sulfur coal, sub-bituminous coal, lignite and the like, which are often inexpensive and considered low quality, is practical due to the ability of the process to remove the SOx and other pollutants as well. as removing CO2. These fiiels may also provide higher levels of co-reactants such as alumina and silica in fly ash carried by the flue gas, producing modified carbonate mineral precipitates with beneficial properties.
[00346] When co-located with a power plant, methods of the invention provide sequestration of substantial amounts of CO2 from the gaseous waste stream procluced by the power plant with a limited energy demand. In some instances, the methods provide for removal of 5% or more, 10% or more.
25% or more, 50% or more, 75% or more of the CO, from the gaseous waste strea.in with an energy demand of 50% or less, such as 30%
or less, including 25% or less. The energy demand is the amount 0- f energy generated by the power plant that is required to operate th.e carbon dioxide sequestration process. In some instances the above levels of CO2 removal are achieve with an energy demand of 20% or less, 15% or less, 10% or less.
[00347] Another type of industrial plant that may be co-located with a precipitation plant of the invention is a cement plant, such as a Portland cement production plant. Fig. 34 provides a schematic of an exemplary Portland cement production fa.cility. In Fig. 34, limestone 400 along with shales and other additives 410 are milled to appropriate size and moved through precalciri.er 500, whi.ch uses waste heat from flue gas 430 to preheat the mixture, utilizing waste heat from kiln 510 to improve onerational efficiency. The preheated mixture enters kiln 510 where it is further heated by burning coal 420. The resultant clinker 480 is collected and stored in silos 570, where it is blended with additives 571 such as ;aypsum, limestone, etc. and ground to desired size in ball mi11580. The product that exits the hall nnill is Portland cement 490, which is stored in cement silo 590 prior to shipment to customers.
[00348] The flue gas 430 that comes from ki'r. 510 conrains both gasPous and parkiculate contaminants. The particulate contaminants are known as kiln dust 440. and are removed from the flue gas via electrostatic precipitators or baghouses 520. The kiln dust so removed is commonly sent to landfill 600, though occasionally kiln dust is recvcled into the kiln, or sold as .a supplementarvi cementitious material. The flue gas is then pulled by fan 540 into wet senabber 550, where the sulfur oxides in the flia.e gas are removed by _1 flQ- Docket No. CLRA-026W0 reaction with a calcined lime slurry, producing a calcium sulfite (e.g., gypsum) slurry 480 which is normally dewatered in reclaim tank 572 and disposed of in laridfill 600. The flue gas 430 exits wet scrubber 430 and is released to the atmosphere via stack 560. T'he flue gas so released. has a high concentration of C02, which is released both by the burning of coal and via the calcination required to oxidize limestone to Portland cement.
[00349] Fig. 35 shows a schematic of an exeniplary co-located cement plant and precipitation plant according to one embodiment of the invention. The process in this example is the same as that in Fig. 34, except that a carbonate precipitation plant replaces the flue gas treatment system of Fig.
34. Once the flue gas exits the precalciner 500, it is pulled by fan 540 tc reactor 630., `;,herein a precipitatiaii_ reaction is initiated utilizing seawater 620 and alkali 625. The resultant slurry 631. i~ pumped via pump 640 to drying station 650, where water 651 is discharged and dried cem.entitious material. 660 is stored for sh:pment to customers. Flue gas 430 is emitted from stack 670 with a portion if not n?.l of the contaminants removed, including mercury, SOx, particulates, and CO2.
[00350] Fig. 35 shows a schematic of an exemplarvi cement plant that does not require a limestone quarry, according to one embodiment of the invention. In this embodiment, the product of reactor 630 may take the form of a relatively pure calcium carbonate durinQ ;lort ions of time during its opPration., and other forms of building materials during other portions of time. In `his example, rather than mined limestone, the precalciner 500 and kiln 510 is charged with a mixture of shale and other ingredients 410 blended with a relatively pure precipitated calcium carbonate 670. Previously mentioned and incorporated by reference T-J.S. Patent Application Publication No. 2009/0020044, published 25 November 2008 details protocols of precipitating an aragonite calcium carbonate from seawater using flue gas. By using the product of the flue gas treatment reactor as a feedstock, the cement plant draws its calcium ion from the sea via the precipitated product, and only requires mined limestone in the first short period of operation until sufficient precipitated calcium carbonate is generated to charge the kiln.
[00351] In some embodiments of the invention, an absorbing solution i.s ccntacted with a gaseous source of carbon dioxide to incorporate carbon dioxide and possibly one or more other component from the gaseous source of carbon dioxide within one apparatus or systetn, such that P.
separate emissions control system or apparatus is not needed. In some embodiments, an absorbing solution is contaeted with a gaseous source of carbon dioxide to incorporate carbon dioxide and possibly one or more other component from the gaseous source of carbon dioxide and the resulting contacted absorbing solution is disposed of without exposing the solution to precipitation conditions.
[00352] In embodiments of the invention, the carbonate precipitation is performed in two stages. The first stage selectively precipitates calcium carbonate, which can then be used as a feedstock for the cement plant as illustrated in Fig. 36. The second precipitation stage can produce a number of dif.ferent materials, including cements, aggregates, above ground carbon, sequestering r;.iateri.als, and the ]ike.
[00353] Portland cement is 60-70% by mass CaO, which is produced by heating CaCO3, requiring heat, and releasing one molecule of COz for every molecule of Ca0 release(l. Because of the additional COZ released -109- Docket No. CLRA-026W0 from the burning of fuel, the output of precipitated CaCO3 from the precipitation plant will exceed the amount required to provide feedstock for the cement plant. In, thi s instance a portion of the time of operation of the precipitation plant may he devoted to production of other cementi*ious materials 660 such as those described in U.S. Patent Application Publication No. 2009/0020044, published 25 November 2008, which is incorporated herein by reference in its entirety.
[00354] The Portland cement 490 produced as shown in Fig. 36 is carbon neutral as the CO2 from its manufacture is sequestered into precipitated carbonate minera1670 and cementitious materials 660. The Portland cement 490 may be sold as is, or blended or intergroimd with cementitious material 660 to produce a blended cement.
[00355] An example of a continuous feed svstem of irtterest is depicted in Fig, 37. In Fig. 37, system 1100 includes water source (e.g., pipe from ocean to provide seawater) 110? ,vfhicb is in fluid communication with reactor 1 I 10. Also present in reactor 1110 is Ca/Mg/OH ion sources and catalysts 1111, which have been added in amounts sufficient to raise the Mg~Ca ion ratio in water present in reactor 1110 to 3 or more. Reactor 1110 may configured as a packed bed colurin, and. configured from bicarbon.ate charging, if desired. CO2 containing gas, e.g., flue gas 1112 is combined with water in reactor 1110 by sparger/bubbler 11.13. The Mg ion source and COZ are combined with the water in reactor 1110 to produce CO2 charged acidic water, which flows out of reactor l 110 at a pH of between 4.8 and 7.5. Next, the CO2 charged acidi c water flows through conduit 1120 where it is cycled with mixing through different levels of alkalinity, e.g., 8.5 and 9.8, with the use of various COZ gas injectors 1121, OH- modulators 1123 (such as introduces of pH elevating agents, electrodes, etc.) and static mixers 1122 positioned at various locations along conduit 1120. The flow rate through conduit 1120 may be controlled as desired, e.¾., to be between 1 GPM
and 1,000,000 GPM, such as 30 GPM and 100,000 GPM and including 4,000 GPM rand 60,000 GPM. The length of conduit 1120 may vary, ranging from 100 ft to 20,000 ft, such as 1000 ft to 7000 ft. At. the end of conduit 1120, as slurry product 1130 is obtained, which slurry product incltides the precipitated CO,-sPquestering product and mother liquor.
The resulting slurry is then forwarded to a liquid-solic? separation apparatus or settling tank, as illustrated at 1140.
[00356] In certain embodiments, two or more reactors m_av be used to carry out the methods described herein.
A schematic of an embodiment usint; two reactors is sholvnl in Figs. 38, 39, and 40. In this embodiment, the method may include a first reactor 1210 and a secon] reactor 1210. In these cases, the first reactor 1210 is used for contacting the initial water, e.g fresh sea.S Nater 1230, with a magnesii.im ion source 1240 and for charging the initial water with CO2 containin;y gas, e g. flue gas 1250 (where this step is also referred to as bicarbonate charging). The flue gas 1250 ma.y be contacted with the water in the first reactor 1210 through a sparger/bubbler 1280. The water is agitated with agitator 1260 to facilitate the dissolution of the magnesium ion source and to facilitate contact of the initial water vnith the CO:, containing gas. In some cases, before the CO2 charged acidic water is transferred to the second reactor 1220, agitation of the CO2 charged acidic water i 1 n Docket No. CLRA-026W0 is stopped, such that undissolved solids may settle by gravity. The CO2 cllarged acidic water is then transferred through conduit 1270 from the first reactor 1210 to the second reactor 1220.
[00357] After transferring the CO2 charged acidic water to the second reactor 1220, the step of carbonate precipitation may be performed. In some cases, a pH raising agent 1290 is contacted with the water in the second reactor 1220 to facilitate formation of the carbonate containing precipitate. The contents of the second reactor 1220 may be agitated with agitator 1295. In certain embodiments, one or more additional steps of CO2 charging and subsequent carbonate precipitation may be performed in the second reactor, as described above.
In these cases, additional CO2 containing gas. e.g. flue gas 1255, is contacted with the water in the second reactor 520 through sparger/bubbler 1285. The resulting slurry product includes the precipitated CO2-sequestering product and mother liquor, which is then forwarded to a water/solids separator or settling tank, as described above.

COMPOSITIONS
[00358] Compositions of the invention may be solutions, solids, or multiphasic materials (e.g., slurries) comprising carbonates, bicarbonates. or carbonates and bicarbonates, optionally of divalent cations such as Ca2+, Mg2+, or combination thereof. The amount of carbon in such compos-itions (e.g., storage-stable carbon dioxide sequestering products such as precipitation ma`.erial) produced by methods of the invention may vary.
In some embodiments, compositions comprise an amount of carbon (as detennined by using protocols described in greater detail below, such as isotopic analysis, e.g.,'3C
isotopic analysis) ranging from 1% to 15% (w/w), such as 5 to 15% (w/w), including 5 to 14% (w/w), 5 to 13% (w/w), 6 to 14% (w/w), 6 to 12%
(w/w), and 7 to 12% (w/w), wherein a substantial a.mei.lnt of the carbon may be carbon that originated (as determined by protocols described in "eater detail below) in the source of CO2. In such embodiments, 10 to 100%, such as 50 to 100%, including 90 to 100% of tho carbon present in composition (e.g., storage-stable carbon dioxide sequestering products such as precipitation material) is from the source of CO2 (e.g., industrial waste gas stream comprising carbon dioxide). In some instances, the arnount of carbon present in the composition that is traceable to the carbon dioxide source is 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, 95% or more, 99% or mcre, including 100%.
[003591 Compositions of the invention (e.g., precipitation material comprising carbonates, bicarbonates, or carbonates and bicarbonates) may store 50 tors or mo-e of C02, su<=h as 100 tons or more of CO;,, including 150 tons or more of CO2, for instance 200 tons or more of COz, such as 250 tons or m_ore of CO2, including 300 tons or more of CO2, such as 350 tons or more of C02, includi.ng 400 tons or more of C02, for instance 450 tons or more of CO2, such as 500 tons or more nf COz, includi.ng 550 tons or more of C02, such as 600 tons or more of CO2, inchzding 650 tons or more of CO,, for instance 700 tons or more of COz, for every 1000 tons of the composition. Thus, in some ernbodimerts, the compositic,i;s of the invention (e.g., precipitation material comprising carbonates, bicarbonates, or carbonates and hicarbonates) coniprise 5% or niore of C02, such as 10% or more of COZ, includin.g 25% or n?ore of CO2, for instance 50%
or more of C02, such as 75%

Docket No. CLRA-026W0 or more of C02, including 90% or more of CO2. Sucli coar.npositions, particularly precipitation material of the invention may be used in the built environment. In sorne einbodiments, the coinposition may be employed as a component of a manufactured item, such as a building material (e.g., component of a cement, aggregate, concrete, or a combination thereof). The composition remains a storage-stable C02-sequestering product, as use of the composition in a manufactured item (such as building material) does not result in re-release of sequestered COZ. In some embodiments, compositions of the invention (e.g., precipitation material comprising carbonates, bicarbonates, or carbonates and bicarbonates), when combined with Portland cement, may dissolve and combine with compounds of the Portland cemer_t without releasing COZ.
[00360] Conditions employed to convert CO2 into car=bonates, bicr.rbonates, or carbonates and bicarbonates may result in one or more additional components a:.icUor co-products (i.e., products produced from the one or more additional components) thereof, wherein. such additional components include sulfur oxides (SOx);
nitrogen oxides (NOx); carbon monoxide (CO); nietals such as anlimony (Sb), arsenic (As), barium (Ba), beryllium (Be), boron (B), cadmium (Cd), chromiutn. (Cr), cobalt (Co), copper (Cu), lead (Pb), manganese (Mn), mercury (Hg), molybdenum (Mo). nickel (Ni), radium (Ra), selenium (Se), silver (Ag), strontium (Sr), thallium (Tl), vanadium (V), and zinc (Zn); partioukit.e rnatter; halides;
orQanics; toxic substances; radioactive isotopes, and the like. In som:, embodiments, such one or more additional components and/or co-products may be part of a solution comprising carbonates, bicarbonates, or carbonates and bicarbonates. In some embodiments, such one or more additional components and/or co-products may be part of precipitation material of the invention by precipitating the one or more additional components and/or co-products along with carbonates, bicarbonates, or carbonates and bi.carbonates, by trapping the one or more additional components and/or co-products in precipitation material comp-ising carbonates, bicarbonates, or carbonates and bicarbonates, or by some combination thereof. Ir some embo(liments, such one or more additional components and/or co-products may be part of a slurry comprising any combination of the foregoing solutions with precipitation materia.l.
[00361] Compositions of the invention may comprise sulfates, sulfites. or the like in addition to carbonate and/or bicarbonates. In some embodiments. compositior_s comprise 70-99.9%
carbonates and/or bicarbonates along with 0.05-30% sulfates and/or sulfites. For examnle, compositions may comprise at least 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%. 95%, or 99.9 i, carbonates and/or bicarbonates. Such compositions may further comprise at least 0.05%, 0.1 %, 0.5%, 1.0%, 5.0%, 10%, 15%, 20 %, 25%, or 30% sulfates and/or sulfites. In some embodiments, compositions of the inveniion comprise sulflar-based compounds of calcium, magnesium, or combinations thereof, optionally precipitated or trapped in precipitation material produced from waste gas streams comprising SOx (e.g., SO2, SO3, etc.). For example, ma.gnesilun and calcium may react to form MgSO4 and CaSO4, respectively, as well as other magnesium- and calcium-containing compounds (e.g., sulfites), effectively removing sulfur from the waste gas stream (e.g., flue gas stream) without a desulfurization step such as flue gas desulfizrization ("FGD"). In addition, coinpositions comprising CaSO4, MgSO4, and related compounds may be fornied without additional releasc of CO2. In instances where Docket No. CLRA-026W0 ,.. , ., . , a . _, ,. ... . _ .. ~ , _ high levels of sulfur-based compounds (e.g., sulfate) are present, the aqueous solution may be enriched with calcium and/or magnesium so that calcium and./or mag~.-tesium are available to form carbonate compounds before, during, or after formation of CaSO4, MgSO.4, and;'or relatec3 compounds. In some embodiments, multiple reaction products (e.g., MgC'O;, CaCOI, CaSO4, rnixtures of the foregoing, and the like) are collected at different stages, while in other embodinlents a single reaction product (e.g., precipitation material comprising carbonates, sulfates, etc.) is collected.
[003621 Compositions of the invention may comprise nitrates, nitrites, and/or the like. In some embodiments, compositions of the invention comprise such nitrogen-based compounds of calcium, magnesium, or combinations thereof, optionally precipitated or t..rapped in precipitation.
materia] produced from waste gas streams comprising NOx (e.t;., NO2, NO;, etc.). For e:carnple, magnesilirn.
and calcium may react to form Mg(NO3)Z and Ca(N03)2, respectively, as well as othc~:~ rn< iesium- and calcium-containin,g compounds (e.g., nitrates), effectively removing nitrogen from the w:?4tp gas stream (e.g., flue gas stream) without a selective catalytic reduction ("SCR") step or non-selective catalytic reduction ("NSCR") step. In addition, compositions comprising Ca(NO3)2, Mg(N03)2, and related compounds may be formed without additional release of CO2.
Compositions of the invention may fizrther comprise other components, such as trace metals (e.g., mercury).
Using mercury as a non-limiting exaniple of a trace metal, compositions of the invention may comprise elemental mercury (H,g ), mercury salts comprisina Hg`'+ (e.g., 1-1gCI2, HgCO;, etc.), mercury salts comprising Hg{ (e.g., Hg,Clz, Hg2CO,, etc.), mercury compotinir e.:omprising Hg2~ (e.g., H~:O, orga.nomercury compounds, etc.), mercury cnmpounds comprising 1HR1 (e.g., Hg2C), organomercury compounds, etc.), particulate mercury (Hg(p)), and the like. In some embodiments, compositions of the invention comprise such mercury-based compounds, optionally precipitated or trapped in p-ecipitation material produced from waste gas streams comprising trace m_etals such as mercury. ?n some embodiments, compositions comprise mercury (or another metal) in a concentration of at least 0.1, 0.5. 1, 5, 10. 50, 100, 500, 1,000, 5,000, 10,000 ppb.
Mercury may react to form HgCO3 or Hg2CO3 as well as other mercury-containing compounds (e.g., chlorides, oxides), effectively removing mercury from the waste gas stream (e.g., flue gas stream) without a specific or non-specific mercury, removal technology. In addition, compositions comprising mercury and and/or other trace metals may be formed without additional release of CO2.
[00363] Precipitation material of the invention may comnrise seve-raJ.
carbonates and!or several carbonate mineral phases resulting from co-precipitation, wherei~-) the nrecipitation material may comprise, for example, calcium carbonate (e.g., calcite) together with magn:sium carbonate (e.g., nesquehonite).. Precipitation material may also comprise a. single carbonate in a si~:.gle mineral phase including, but not limited to, calcium carbonate (e.g., calcite), magnesium carbonate necquchonite), calcium magnz~sium carbonate (e.g., dolomite), or a ferro-carbo-aluminosilicate. As different carbonatcs mr;v he precipitated in sequence, the precipitation material may be, dependint; upon the conditions t.ander whictii it was obtained, relatively rich (e.g., 90% to 95%) or substantially ricb_ (e.g., 95%-99.90//,)) in one carbonate and/or one mineral phase, or the precipitation material may comprise an. amount of other carhonates and/or other mineral phase (or phases), -1 13- Docket No. CLRA-026W0 wherein the desired mineral phase is 50-90% of the precipitation material. It will be appreciated that, in some embodiments, the precipitation material may comprise one or more hydroxides (e.g., Ca(OH)2, Mg(OH)2) in addition to the carbonates. It will also be appreciated that any of the carbonates or hydroxides present in the precipitation material may be wholly or partially amorphous. In some embodinients, the carbonates and/or hydroxides are wholly amorphous. It will also be appreciated that anv of the carbonates or hydroxides present in the precipitation material may be wholly or partially crystalline. In some enibodiments, the carbonates and/or hydroxides are wholly crystalline.
[00364] While many different carbon:j e-containing sali s and compounds are possible due to variability of starting materials, precipitation material comprising magnesium carbonate, calcium carbonate, or combinations thereof is particularly useful. T'recipitation material niay comprise two or more different carbonate compounds, three or more different carbonate compounds, four or ?.nore different carbonate compounds, five or more diff rent carbonate compounds, etc., including non-distinct, amorphous carbonate compounds. Precipitation material of the invention mav comprise compounds having a molecular formulation X,,,(CO3),2f wherein X is any element or combination of elements that can chemically bond with a carbonate group or its multiple and m and n are stoichiometric positive integers. In some embodiments, X
may be an alkaline earth metal (elements found in co'umn TIA of the periodic table of elements) or an alkali metal (elements found in column IA. of the periodic tahle of elernents), or some combin.ation thereof. In some embodiments, the precipitation material comprises doloinite (CaM,',)7(C03)2), protodolomite, huntite (CaMg3(C03)4), and/or sergeevite (C'a,Mg1 i(C03)13=H10), which are carbonate minerals comprising both calcium and magnesium. In some embodiments, the precipitation material comprises calcii.un carbonate in one or more phases selected from calcite, arat;onite., vaterite, or a combination the.reof. In some embodiments, the precipitation material comprises hydrated forms of calcium carbonate (e.g., Ca(COz)=nH,O) where there are one or more structural waters :in the molecular formula.) selected from ikaite (CaCO3=6H20), amorphous calcium carbonate (CaCO3=nH)O), monohydroca?.cite (CaCO3=H2O), or combinations thereof. In some embodiments, the preci?aitation material comprises r_aagnesium carbona.te., wherein. tl-~e maenesium carbonate does not have any waters of hydration. In some embod;r.,ents, the precipitation material comprises magnesium carbonate, wherein the magnesium carbonate may have any of a nur,lber of different waters of hydration (e.g., Mg(CO,)=nH?O) selected from 1. 2, 3, =1, or more than 4 waters of hydration. In some embodiments, the precipitation material comprises 1, 2, 3, 4, or more than 4 different magnesium carbonate phases, wherein the magnesium carbonate phases differ in the number of waters of hydration. For example, precipitation material mav c.omprise magnesite (MgCO1;). barring'onite (MaCO,=2H,O), nesquehonite (MgCO3=3H20), lansfordite (MgCO=5112O), and amortihous mag!iesium carhonat,:.
In same embodiments, precipitation material comprises magnesium carbonatcs that include hydroxide and waters of hydration such as artinite (MgCO3=Mg(OH)2=31-.Iz0). hydroma.gnesite ('Vip5(CO3)1,(OT-T)2=3H1O1, or combinations thereof. As such, precipitation material may comprise earhonates o'' calcium, ma<_?nesiuni, or combinat.ion.s thereof in all or some of the various states of hydration listed herein Precipitation rat.e may also influence the nature of the ~ ~ ~' Docket No. CLRA-026W0 precipitation material with the most rapid precipitation rate achieved by seedi.ng the solution with a desired phase. Without seeding, rapid precipitation rna.y be achieved by, For example, rapidly increasing the pH of the precipitation reaction mixture, which results in more arriorphous constituents. Furthermore, the higher the pH, the more rapid the precipitation, which precipitation results in a more amorphous precipitation material.
[00365] In some instances, the amount by weight of calciuin carbonate compounds in the precipitation material may exceed the amount by weight of magnesium carbonate compounds in the precipitation material.
For example, the amount by weight of calcium carbonate compounds in the precipitation material may exceed the amount by weight magn:.sium carhonate compounds in the precipitation material by 5% or more, such as 10% or more, 15% or more, 20% or m.ore, 25% or niore, 30% or more. In some instances, the weight ratio of calcium carbonate compounds to magnesium carbonate compounds in the precipitation material ranges from 1.5-5 to 1, such as 2-4 to 1, including 2-3 to 1. In some instances, the amount by weight of magnesium carbonate compounds in the precipitation material m:a.y exceed the arlount by weight of calcium carbonate compounds in the precipitatior. m.ater?al. For example, the amount by weight of magnesium carbonate compounds in the precipitation material r_1,qy exceed the amount by weight calcium carbonate compounds in the precipitation material by 5% or more, such as 10% or more, 15% or more, 20% or more, 25% or more, 30% or more. In some instances, the weight ratio of magnesium carbonate compounds to calcium carbonate compounds in the precipitation material ranges from 1.5-5 to 1, such as 2-4 to 1, including 2-3 to 1.
[00366] Precipitation material produced by methods of the invention may comprise carbonate compounds that, upon combination with. fresh water. dissolve the initial precipitation material to produce a fresh water precipitation material comprising carbonate compounds that are more stable in the fresh water than the carbonate compounds of the initial precipitation material. (Although the carbonate compounds of the initial precipitation material may dissolve upon combination with fresh water, a new composition is produced. Thus, CO2 gas is not liberated in significant amounts, or in some cases, at all, in any such reaction.) The carbonate compounds of the initial precipitation material m.ay be compounds that are more stable in salt water than they are in fresh water, such that the carbonate compounds may be viewed as metastable in salt water. The amount of carbonate in precipitation material, as determined by coulometric titration, m.ay be 4001'o or higher, such as 70% or higher, including 80% or higher.
[00367] Adjusting major ion ratios during r,recipitation may influence the nature of the precipitation material.
Major ion ratios have considerable influence on polymorph formation. For example, as the magnesium:calcium ratio in the water increases, aragonite becomes the maior polymorph of calcium carbonate in the precipitation material over low-mah;nesium calcite. At low magnesium:calci.um ratios, low-magnesium calcite becomes the major polymorah. In some embodiments, where Ca2`
and Mg2+ are both present in the water, the ratio of Ca 24 to Mg2+ (i.e., Ca`:Mg2) in the water is between 500:1 and 1:500, such as between 100:1 and 1:100, such as between 50:1 and 1:50, such as between 20:1 and 1:20, such as between 10:1 and 1:10. In some embodiments, where CaZ'- and %'Ig2} are both present in the water, the ratio of Ca2+ to Mg2+ (i.e., Ca2+:Mg2+) in the water is between 5:1 and 1:1. In some embodiments, where Ca2+ and Mg2+ are -115- Docket No. CLRA-026W0 both present in the water, the ratio of Ca2T to l`/Ig2} (i.e,, CaZ+:Mg2r) in the water is 4:1. In some embodiments, where Ca2+ and Mg2+ are both present in the water, the ratio of Ca:" to Mgz }(i.e., Caz+:Mg2T) in the water is between 1:1 and 1:10. In sorrie embodiments, where Ca2+ and Mg2-' are both present in the water, the ratio of to Ca2+ (i.e., Mg2+:Ca2+, which is the reverse of Caz+:Mg2+) in the water is between 10:1 and 1:1, such as Mgz+
between 5:1 and 2:1. In some embodiments, where CF" '+ and Mg2- are bot:h present in the water, the ratio of Mg2+ to Caz+ (i.e., MgZ+:Ca` , which is the reverse of Ca'+:Mg`+) i;i the water is 4:1. In some embodiments, where Ca2+ and Mg2+ are both present, the ratio of Ca`1 to Mg2+ (i.e., Ca21:MgZY) in the precipitation material is between 10:1 and 1:1; 1:1 and 1:2.5; 1:2.5 and 1:5; 1:5 and 1:10; 1:10 and.
1:25; 1:25 and 1:50; 1:50 and 1:100; 1:100 and 1:150; 1:150 and 1:200; 1:200 and 1:250; 1:250 _-und 1:500;
1:500 and 1:1000, or a range thereof. For example, in some embodinlents, the ratio of Ca2+ to T,Ig'+ in the precipitation. material is between 1:1 and 1:10; 1:5 and 1:25; 1:10 an;l 1:50; 1:25 and 1: i00; 1:50 and 1:500;
or 1:100 and 1:1000. In some embodiments, the ratio of Mg'+ to C:3 2` (i.e., Mg2 :Ca2 in the precipitation material is between 1:1 and 1:2.5;
1:2.5 and 1:5; 1:5 and 1:10; 1:10 and 1:25; 1:25 and 1:50; 1:50 and 1:100;
1:100 and 1:150; 1:150 and 1:200;
1:200 and 1:250; 1:250 and 1:500; 1:500 and 1:1000, or a range thereof. For exam_ple, in some embodiments, the ratio of MgZ+ to Ca2+ in the precipitation material. is between 1. - 1 and l: 10; 1:5 and 1:25; 1:10 and 1:50;
1:25 and 1:100; 1:50 and 1:500; or 1:100 and 1:1000 [00368] Due to variability of starting materials, carbonate-containing salts and cotnr)ounds comprising counterions other than calcinin or magnesium are tossible. For example, in some embodiments, compositions of the invention (e.g., prec=pitation material) ; ompris.e calcium carbonate in the form of aragonite. In such embodiments, calcium may he replaced by a number o' different -r.ietals including, but not limited to strontium, lead, and zinc, each of which, in cne fornl or another, may be fou.n.d in one or more starting materials (e.g., waste gas stream. source of proton-removing agents, source of divalent cations, etc.) of the invention. Compositions may comprise, for example, mossottite, which is aragonite rich in strontium, or compositions may comprise a mixture of aragonite and stroritianits (e.g., (Ca,Sr)COI). Compositions may comprise, for example, tarnowitzite., which is aragonite rich in lea(l.., or compositions may comprise a mixture of aragonite and cerussite (e.g., (Ca,Pb)CO3). Compositions may comnrise, for example, nicholsonite, which is aragonite rich in Zn, or compositions may comprise a mixture of aragonite a1id smithsonite (e.g., (Ca,Zn)C03). In view of the foregoing exemplarv embodiments, compositions (e.g., precipitation material) may comprise carbonates, bicarbonates, or carbonates and bicarbonates of As, Ag, Ba. Be, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Se, Sb, Ti, V, or Zn. By way of examp'le, composition.s of the invPntio i 1-nay comprise carbonates of Ag, Ba, Be, Cd, Co, Cu, Ni, Pb, Tl, Zn, or combinations thereoi:
Carbonates, bicarbonates, or carbonates and bicarbonates of the foregoing metals m_ay be independently forrned. (e.g., strontianite) or exist in a magnesium and/or calcium matrix (e, g., mossottite). Metals sucii as As, Ag, Ba, Be, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Se, Sb, TI, V, and Zn may be provided by a waste gas stream, a source of proton-removing agents, a source of divalent cations, or a combination thereof. Meta?.s and other components found in such source (e.g., waste gas stre,ar%s, sources of proton-r,moving agents. sources of divalent cations) that do not -1 1 6- Docket No. CLRA-026W0 form carbonates, bicarbonates, or carbonates and bicarbonates may be trapped in or adsorbed on precipitation material.
[00369] Precipitation material, which comprises one or more synthetic carbonates derived from industrial C02, reflects the relative carbon isotope composition (513C) of the fossil fuel (e.g., coal, oil, natural gas, or flue gas) from which the industrial CO2 (from combustion of the fossil fuel) was derived. The relative carbon isotope composition (S' 3C) value with units of %o (per mille) is a measure of the ratio of the concentration of two stable isotopes of carbon, namely 12C and13C, relative to a standard of fossilized belemnite (the PDB
standard).

S13C %o =[(13C/12C sample -"C/"C PDB standard) /("C/12C PDB standard)1 x 1000 [003701 As such, the S13C value of the synthetic carrona.te-containin, precipitat.ion material serves as a fingerprint for a CO2 gas source. The 813C value may vary from source to source (i.e., fossil fuel source), but the S13C value for composition of the invention l;enerally, but not necessarily, ranges between -9%o to -35%0.
In some embodiments, the 8 13C value for the synthetic carbonate-containing precipitation material is between -1%o and -50%o, between -5%o and -40%o, between -5%õ and -35%o, between -7%o and -40%o, between -796o and -3596o, between -9%o and -40 %o, or between -9%o and -35%o. In snme e.nlbodiments, the 8'3C value for the synthetic carbonate-containing precipitation material is less than (i.e., more negative than) -3%o, -5%0, -6%o, -7%o, -8%o, -9%o, -10%0, -11%0, -12%o, -13%o; -14%o, -1 S%o, -16%o, -17%o, -18%0, -19%0, -20%o, -21%o, -22 io, -23%o, -2496o, -25%o, -26% , -27 io, -28%o, -29%o, -30%0, -31%o, -32%0, -33%0, -3496o, -35%0, -36%w, -37%o, -389'.o, -39%o, -40%o, -41%0, -42%o, -43%o, -44%0, or -45%o, whereir. the more negative the S"C value, the more rich the synthetic carbonate-containing conlposition is in12C. t~ny suitable method may be used for measuring the S13C value, methods including, but no limited to, mass spectrometry or off-axis integrated-cavity output spectroscopy (off-axis ICOS).
[00371] In addition to magnesium- and calcium-containing products of the precibitation reaction, compounds and materials comprising silicon, aluminum, iror., and others may also be prepared and incorporated within precipitation material with methods and systems of the invention.
Precipitation of such compounds in precipitation material or addition of such compounds tc the precipitation material may he desired to alter the reactivity of cements comprising the precipitation material resulting from the process, or to chazige the properties of cured cements and concretes made from them. Material comprising inetal silicates may be added to the precipitation reaction mixture as one source of these components, to produce carbonate-containing precipitation material which contaans one or more components, such as amorphous silica, amorphous aluminosilicates, crystalline, silica, calc]uri silicates, calcium ahtmin.a silicates, etc. In some embodiments, the precipitation material comprises carbonates (e.g., cal.eium carbonate, magnesium carbonate) and silica in a carbonate:silica ratio between 1:1 and l:1.5; 1:1 _5 an.d 1:2;
1:2 and 1:2.5; 1':2.5 and 1:3; 1:3 and 1:3.5; 1:3.5 and 1:4; 1:4 and 1:4.5; 1:4.5 and 1:5; 1:5 and 1:7.5; 1:7.5 and 1:10; 1:1.0 and 1:15; 1:15 and 1:20, Docket No. CLRA-026W0 ._ .t=

or a range thereof For exantple, in sorne ;r7bodimeTi+s, the precip;tati.on material comp.rises carbonates and silica in a carbonate:silica ratio between 1- 1 and 1:5, 1:5 atid 1:10, ;,r 1:5 and 1:20. In some embodiments, the precipitation material comprises silica and carbonates (e.g., calcium carbonate, magnesium carbonate) in a silica:carbonate ratio between 1:1 and 1:1.5; 1:1.5 and 1:2; 1:2 and 1:2.5;
1:2,5 and 1:3; 1:3 and 1:3.5; 1:3.5 and1:4; 1:4and1:4.5; 1:4.5and1:5; 1:5and1:7.5; 1.:7.5and1:10; 1:10and1:15; 1:
15 and 1: 20, or a range thereof. For example, in some embodiments, the precipitation material comprises silica and carbonates in a silica:carbonate ratio between 1:1 and 1:5, 1:5 and 1:10, or 1:5 and 1:20. In general, precipitation material produced by methods of the invention comprises mixtures of silicon-based ..m.aterial an.d at least one carbonate phase. In general, the more rapid the reaction rate, the more silica is incorporated with the carbonate-containing precipitation material, provided silica is nresent in the preciaitation. reaction mixture (i.e., provided silica was not removed after digestion of material comprising metal silicates).
[00372) Precipitation material may be in a storage-stable form (wl ich may sii:nply be air-dried precipitation material), and may be stored above ground under exnu;:.ed conditions (i.e., open to the atmosphere) without significant, if any, degradation (or loss of C02) for extended duration.s. In some embodiments, the precipitation material may be stable under exposed conditions for 1 year or lor..ger. 5 years or longer, 10 years or longer, 25 years or longer. 50 years or longer, 100 years or longer,, 250 years or longer, 1000 years or longer, 10,000 years or longer. 1,000,000 years or lonuer, or even 100,000,000 vea.rs or longer. A storage-stable form of the precipitation materi.al may be stable under a variety of different environment conditions, for example, from temperatures ranging from -100 C to 600 C and humidity ranging froni 0 to 100%, where the conditions may be calm., windy, or storm,y_ As the storzge-stable form of the precipitation material undergoes little if any degradation while stored above ground under normal rainwater pH, the amoiuit of degradation, if any, as measured in ternis of CO2 aas release from the product, does not exceed 5% per ,year, and in certain embodiments will not exceed 1% per year or 0.001 % per year. Indeed, precipitation material provided by the invention does not release more than 1%, 5%, or 10% of its total CO;, whem exposed to normal conditions of temperature and moisture, including rainfall of nonnal pH for at least 1, 2, 5, 1.0, or 20 years, or for more than 20 years, for example, for more than 100 years. In some embodim,;nts, the precipitation material does not release more than 1% of its total CO, when exposed to normal conditions of temperature and moisture, including rainfall of normal pH for at least 1 year. In some embod iments, the prtxipitation material does not release more than 5% of its total CO_ when exposed to normal conditions of temperature and moisture, including rainfall of nornial pIi for at least 1 yeag=. In soine emboclit.ne,nts, the precinitation material does not release more than 10% of its total CQ> wheai exposed to normal conditions of temperature and moisture, including rainfall of normal pH for at least 1 year. ln some embodiments, the precipitation material does not release more than 1% of its total COZ wben exposed to nortnal conditions of temperature and moisture, including rainfall of normal pH for at least 10 years. Tn some em'noriiments, the precipitation niaterial does not release more than 1% of its tot-al CO2 , when exposed to normal conditions ryf temperature and moisture including rainfall of normal pH for at least 100 years. In some em??odiments, the precipitation mate.rial does Docket No. CLt2A-026W0 -Ai not release more than 1% of its total CO2 when exposed to normal conditions of temperature and moisture, including rainfall of normal pH for at least 1000 years.
[00373] Any suitable surrogate marker or test that is reasonably able to predict such stability may be used. For example, an accelerated test comprising conditions of elevated ternperature ar~d/or moderate to more extreme pH conditions is reasonably able to indicate stability over extended periods of time. For example, depending on the intended use and environment of the precipitation material, a sample of the precipitation material may be exposed to 50, 75, 90, 100, 120, or 150 C for 1, 2, 5, 25, 50, 100, 200, or 500 days at between 10% and 50% relative humidity., and a loss less than 1%, 2%, 39/o, 4%, 5%, 10%, 20%, 30%, or 50% of its carbon may be considered sufficient evidence of stability of precipitation material of the invention for a given period (e.g., 1, 10, 100, 1000, or more than 1000 years).
[00374] Any of a number of suitable methods nlay be used to test the stability of the precipitation material including physical test methods and chemi.cal test methods, wherein the methods are suitable for determining that the compounds in the precipitation material are similar to or the same as naturally occurring compounds known to have the above specified stabili.ty (e.g., liinestone). COZ ^ontent of the precipitation material may be monitored by any suitable -nethod, one such non-limiting example being coulometry. Other conditions may be adjusted as appropriate, including pH, pressure, T;JV radiation, arld the li.ke, again depending on the intended or likely environraen.t. It will be appreciated that any suitable conditions may be used that one of skill in the art would reasonably conclude indicate the requisite stability over the indicated time period. In addition, if accepted chemical knowledge indicates that the precipitat.ion material would have the requisite stability for the indicated period this may be used as wel.;, i.n. addition to or in place of actual measurements.
For example, some carbonatF compound.s that may be part of a precipitation nlaterial of the invention (e.g., in a given polymorphic form) may be well-known geologically and known to have withstood normal weather for decades, centuries, or even millennia, without appreciable br.eakdown. and so have the ?-equisite stability.
[00375] The carbonate-containing precipitation materiGi., which serv.s to sequester CM: in a form that is stable over extended periods of time (e.g., geologic time scales), may be stored for extended durations, as described above. The precipitation material, if needed to achieve a certain ratio of carbonat;,s to silica, may also be mixed with silicon-based material (e.g., from separated ,ilicon.-based material after material com.prising metal silicates digestion; commercially available SiO~: etc:.) to form nozzolanic mat.~..~rial. Pozzolanic materials of the invention are siliceous or aluminosiliceous materials which, wher_: combin.ed with ar alkali such as calcium hydroxide (Ca(OH)2), exhibit cementitinus propert:es hy i:orming calcium sil'acates and other cementitious materials. Si02-containing materials such as volcanic ash, fly ash. silica fizme, high reactivity metakaolin, and ground granulated blast fizrnace slat*, and the like may be 11sed t:o fortifv compositions of the invention producing pozzolanic materials. In some embodiments. pozzolanic materials of the inve,ntion are fortified with 0.5% to 1.0%, 1.0% to 2.0%; 2.0% to 4.0 ./0, 4.0`,o to 6.0%, fi.Mo to 8.0 ~, 8.0% to 10.0%, 10.0% to 15.0%, 15.0% to 20.0%, 20.0% to 30.0%. 30.0% to 40.0 io, 40,0% to 50.0%, or an overlapping range thereof, ' ' 9 Dccket No. CLRA-026W0 an Si02-containing material. Such Si02-containing material may be obtained from, for example, an electrostatic precipitator or fabric filter of the in.vention.
[003761 As indicated above, in some embodiments, precipitation material comprises metastable carbonate compounds that are more stable in salt water than in fresh water, such that upon contact with fresh water of any pH they dissolve and re-precipitate into other fresh water stable minerals. In certain embodiments, the carbonate compounds are present as small particles, for= example, with particle sizes ranging from 0.1 gm to 100 gm, 1 to 100 gm, 10 to 100 m, 50 to 100 gm as determined by scanning electron microscopy (SEM). In some embodiments, particle sizes of the carbonate compounds range from 0.5 to 10 fim as determined by SEM. In some embodiments, the particles size exhibit a single modal distribution. In some embodiments, the particle sizes exhibit a bimodal or multi-modal distribution. In certain embodiments, the particles have a high surface are ranging from, for example, 0.5 to 100 m2/gm, 0.5 to 50 m2/gm, or 0.5 to 2.0 m2/gm as determined by Brauner, Emmit, & Teller (BET) Surface Area Analysi.s. In so_ne embodim nts, precipitation material may comprise rod-shaped cr,,stals and/or amorphous solids. T'he rod-shaned crystals may vary in structure, and in certain embodiments :have a length to diameter ratio ranging fi=om 500 to 1, 250 to 1, or 10 to 1. In certain embodiments, the length of the crystals ranltes from 0.5 gni to 500 m, I an to 250 gm, or 5 gm to 100 pm. In yet other embodiments, subst.antially completely amorphous solids are produced. [003771 Spray-dried material (e.g., precinitation material, silicon-based material, pozzolanic material, etc.), by virtue of being spray dried. may have a consistent particle size (i.e., the spray-dried material may have a relatively narrow particle size distribution). As su.ch, in some embodiments, at least 50%, 60%, 70%, 80%, 90%, 95%, 97%, or 99% of the spray-dried material faJls within. fl 0 microns, +20 microns, 30 microns, 40 microns, 50 microns, 75 microns, f 100 microns, or 250 microns of a given mean particle diameter. In some embodiments, the given mean. particle diameter is between 5 and 500 microns. In some embodiments, the given mean particle is between 5 and 250 microns. In some embodimen*s, the given mean particle diameter is between 5 and 100 microns. In some embodiments, the given mean particle diameter is between 5 and 50 microns. In some embodiments, the given mean particle diameter is between 5 and 25 microns. For example, in some embodiments, at 1Past 70% of the, spray-dried material falls within 50 microns of a given mean particle diameter, wherein the given mean particle diameter is between 50 and 500 microns, such as between 50 and 250 microns, or between 100 and. 200 microns. Such spray-dried material may be used to manufacture cement, fine aggregate, mortar, coarse aggregate; coiicrete, and/or pozzolans of the invention;
however, one of skill in the art will recognize that manufacture of c?.m.ent, fine aggregate, mortar, coarse aggregate, concrete, and/or pozzolans does not requi-e spray-dried precipitation material. Air-dried precipitation material, for example, may also be used to inanufactZ ire cement, fine aggregate, mortar, coarse aggregate, concrete, and/or pozzolans of the invention.

EXAMPLES

-1 ~n Docket No. CLRA-026W0 [00378] In combination witli the above descri.ptiorr, the following e~s:amples provide those of ordinary skill in the art with a complete disclosure and description of how to make and use the invention. The examples are presented to provide what is believed to be the most useful and readily understood procedural and conceptual description of certain embodinients of the invention. As sz zch, the examples are not intended to limit the scope of what the inventors regard as their invention, nor do the exainples represent all of the experiments or the only experiments performed. Efforts have been made to ensure accuracy with respect to numbers used (e.g., amounts, temperature, etc.), but some exper-imental errors and deviations sliould be accounted for. Unless indicated otherwise, parts are parts by weight, moler,ular v,reight is weight avera.ge molecular weight, temperature is in degrees Centigrade, and pressure is at or near atrlospheric;.

[00379] Example I. Precipitation of P00099 [00380] A. P00099 Precipitation process [00381] The following protocol was used to produce the P00099 precipita.te.
380 T. of filtered seawater was pumped into a cylindrical polyethylene 60J -cone bottom graduated tanlc. This reaction tank was an open system, left exposed to the ambient atmosphere. The reaction tank was constantly stirred using an overhead mixer. pH, room temperature, and water temperature were constantly monitored throughout the reaction.
[00382] 25 g of granulated (Ca,Mg)O (a.k.a., dolime or calcined dolomite) was mixed into the seawater.
Dolime that settled to the bottom of the tank was manually re-circulated from the bottom of the tank through the top again, in order to facilitate adequate mixing and dissolution of reactants. A second addition of 25 g of dolime was performed in an identical manner, inclu.diIQ a manual recirculation of settled reactant. When the pH of the water reached 9.2, a gas mix.tttre of 10% CO, (and 90% compressed air) was slowly diffused through a ceramic airstone into solution. When the pH of the solution fell to 9Ø, another 25 g addition of dolime was added to the reaction tank, which caused tlle pH to rise again. The additions of dolime were repeated whenever the pH of the solutior.~ dropped to 9.0 (or below), until a total of 225 g were added.. A
manual recirculation of settled reactant was performed in between each dolime addition.
[00383] After the final addition of dolime, the continuous diffizsio.n of Qas through the solution was stopped.
The reaction was stirred for ar additional 2 hours. r1,,,.ring this time, the pH contirued to rise. To maintain a pH between 9.0 and 9.2, additional gas was diffused through tlie; roaction when !a?e pH rose above 9.2 until it reached 9Ø Manual re-circulations of settled reactart were also perforrned 4 ti.mes throu.ghout this 2 hour period.
[00384] 2 hours after the final. addition of dolime, stir! ing, gas dif.fasion and recirculation of settled reactant was stopped. The reaction tanlc was left i.tndistit:bcO for 15 hours (open to the atmosphere).
[00385] After the 15 hour period., super.natan.t was rf.mnvFd through the top of the reaction tank using a submersible pump. The remaininry mixture was removed through the bottom of the tank. The collected ' ~ ~ - Dockel No. CLRA-026W0 mixture was allowed to settle for 2 hours. After settling, the supernatant was decanted. The remaining slurry was vacuum filtered through 11 m pore size filter paper, in a Buchner funnel.
The collected filter cake was placed into a Pyrex dish and baked at 110 C for 24 hours.
[00386] The dried product was ground in a ball mix and fractioned by size through a series of sieves to produce the P00099 precipitate.

[00387] B. Materials analysis [00388] Of the different sieve fractions collected, only the fraction.containing particles retained on the 38 m-opening sieve and passing through the 75gm-opening sieve was used.

[0038911. Chemical characteristics 1003901 The P00099 precipitate used for the blend was analyzed for elemental composition using XRF.
Results for the main elements are reported for the QUIKRETETM type I/II
Portland cement used in this blend as well as for the P00099 precipitate in Table 4. below.

Table 4. XRF analysis of the type UII Portland cement and P00099-002 used in this blend.
Sample Na.,O MgO Alz0; Si02 PZO5 SO3 Cl K20 CaO Fe203 Sr CO3 (%) (%) (%) (%) (ppm) N (%) (%) (%) (%) (ppm) ( fo diff OPC1 2.15 1.95 4.32 20.31 2336 2.54 0.072 0.36 62.88 3.88 1099 0.002 P00099 1.36 3.44 0.14 0.083 462 0.65 1.123 0.04 45.75 0.12 3589 46.82 [00391) The XRD analysis of this precipitate indicates the presence of aragonite and maganesium calcite (composition close to Mgo 1Ca0 ,.9CO3) and in ininor atnoa.nts, brucite aald halite (Table 5). The FT-IR analysis of the P00099 precipitate confrmed the presence of' Eragonite, calcite, and brucit.e.

Table 5. XRD analysis of this precipitate.

Sample Aragonite Magnt=-si xrn Calcite Bnicite Halite P00099 79.9 17.1 2.8 0.2 [00392] The total in.organic carbon content measltrea by c,oulometry ;.s in fa:r agree:,ment with the same value derived from the XRD Rietveld estimated compositio~.~ coupled w;th XRT
elcmcrital composition. Table 6 provides a coulometric analysis of P00099 compared to % C derived from XRD/XRF data -122- Docket No. CLRA-026W0 Table 6. Coulometric analysis of P00099 compared to % C'derived from XRD/XRF
data.
Total C from coulometry Total C derived from other analytical data 10.93f0.16% 11.5%
[0039312. Physical characteristics [00394] SEM observations on the precipitate confinned the dominance of aragonite (needle-like) as well as the size of the particle agg?omerates. The detern;ined BE'T' specific surface areas ("SSA") of the Portland cement and the P00099 precipitate are given in Table 7.

Table 7. BET specific surface areas ("SSA") of the Portland cement and the P00099 precipitate.
Type UIl Quikrete Portland cement P00099 1.18f0.04m/g 8.31 0.04m/g [00395] The particle si7e distribution ivas detetrninv.xl after 2 mirl of pre-son'cat.ion to dissociate the agglomerated particles.

[00396] Example II. Use of Fly Ash as an A'kali. So:rc,-, [00397] A. Methods [00398] 500 mol of seawater (initial pH = 8,01) was continuously stirred in a glass beaker using a magnetic stir bar. The pH and temperature of the reaction was continuously monitored.
Class F fly ash (- 10% CaO) was incrementally added as a powder, allowing the pH to equilibrate in between additions.

[00399] B. Results and Observations:

[00400] After the additions of 5.00 g of fly ash the pI-I i eached 9.00.
[00401] 34.14 g --> pH 9.50 [00402] 168.89 g --> pH 9.76 [00403] 219.47 g --> pH 10.94 [00404] 254.13 g --> pH 11.20 1004051300.87 g --> pH 11.28 [00406] (Amounts of fly ash listed are the cumulative totals, i.e. the total amount added at that point in the experiment.) -123- Docket No. C.LRA-026W0 _ .. .... .. _.. _ , .. . ~.>. ,._r _ [00407] Much more fly ash was needed to raise the pH of the seawater than distilled water. The initial pH
raise (8 to 9) required much less fly ash than the further raises. The pH
remained fairly stable around 9.7 for much of the reaction. The rate of rate of pH increase went up after - 10. Also of note was an initial drop in pH
when the fly ash was added. This drop in pH is quickly overcome by the effects of the calcium hydroxide.
SEM images of vacuum dried slurry from the reaction showed some spheres of the fly ash that had partially dissolved. The remaining spheres also seemed to be embedded in a possibly cementitious material.

[00408] C. Conclusions [00409] In fresh (distilled) water, it was founc3 that small amounts of class F fly ash (< 1 g / L) immediately raised the pH from 7 (neutral) to - 11. The small amount necessary to raise the pH is most likely due to the unbuffered nature of nature of distilled water. Seawater is highly buffered by the carbonate system, and thus it took much more fly ash to raise the pH to similar levels.

[00410] Example III. Production of High Yields [00411] A. Process 1 [00412] A 20% CO2 / 80% Air gas mixture was sparged into 11, of seawa`er until a pH <5 was reached. Once reached, 1.0 g of Mg(OH)2 was added to the 11, of car'~-~onic acid/seawater solution. The 20/80 gas mixture continued to be sparged for 20 minutes to ensure maximal dissolution of the Mg(OH)2 and gases. After dissolution, sparging was stopped and 2M NaOH was added until a pH of 9.8 was reached. Sparging of the 20/80 gas was resumed until a pH of 8.5 was reached. 2M NaOH and counter-additions of the 20/80 gas were continued maintaining a pH range between 8.5 and 9.8 until a total of 200ml of 2M NaOH was added. A
yield of 6.91 g was observed having a Coulometer reading of 10.6% carbon (-80%
carbonate).

[00413] B. Process 2 [00414] A 20% CO2 / 80% Air gas mixture wac sparged into 1 L of seawater until a pH <5 was reached. Once reached, 2.69g of Mg(OH)2 was added to the 1 L of carbonic acid/seawater solution. The 20/80 gas mixture continued to be sparged for 20 minutes to ensure maximal dissolution of the Mg(OH)~ ar_d gases. After dissolution, sparging was stopped and 2M NaOH was added until a pH of 9.8 was reached. Sparging of the 20/80 gas was resumed until a pH of 8.5 was reached. 2M NaOH and counter-additions of the 20/80 gas were continued maintaining a pH range between 8.5 and 9.8 until a total of 200m1 of 2M NaOH was added. A
yield of 10.24g was observed having a Coulometer reading of 9.7% carbon (-75%
carbonate).

1 ~4- Docket No. CL=RA-026W0 [00415] SEM, EDS, and X-Ray Diffraction of the precipitated carbonates showed amorphous and crystalline Ca and Mg carbonates, and also the presence of Ca/Mg carbonates. Pictures of the precipitates are provided in Figs. 41 and 42.

[004161 C. Process 3 [00417] CO2 was sparged into 1 L seawater until a pH 7 or lower was reached. 0 to 5.Og Mg ion supplement referred to as "Moss Mag" and obtained from Calera Corporation's Moss Landing site (which is the former site of the Kaiser Aluminum & Chemical Corporation and National Refractorie in Moss Landing California, where the supplement is Mg rich waste product found in tailings ponds of the site) was added while mixing and continuing to sparge COZ. 0.1 75ppm A12(SO4); was added. CO2 was continued to be sparged and base was added while maintaining a pH between 7 and 8 ending at a pH of 7. Sparging of COZ was stopped and base was added until a pH between 9.0 and 10.4 was reached. As shown in Fig.
43, the above reaction conditions favor the formation of amorphous carbonate compound precipitates.
The resultant amorphous precipitate product is readilv spray dried to produce a dry product.

[00418] D. Process 4 [00419] As shown in Figs. 38, 39, and 40, in certain ernbodiments, a multi-step, multi-reactor process is used to carry out the methods disclosed herein. In the first reactor, a magnesium ion. source obtained from a Moss Landing, California site (hereinafter referred to as Mo-ss Mag), was put into solution using carbonic acid and agitation. The pH of the seawater ir,. the first reactor was maintained a pH
of 7.0 or less during Moss Mag dissolution. In certain embodiments, 1.0 gram of 50-150 m Moss Mag was dissolved into solution per 1L of seawater. A pH of 6.2-6.6 or a hardness reading >0.08 grams/liter indicated that the appropriate amount of Moss Mag was dissolved in solution. A.source of CO2, e.g. flue gas, was sparged into the water in the first reactor. About 40-50% of the total flue gas consumed during the entire reaction is dissolved into the seawater in this step. Flue gas was sparged until the pH no longer responded to flue gas dissolution, which took approximately 30-60 minutes. Agitation was stopped to allow unreacted Moss Mag, sand or other large particles to gravity settle before transferring the CO2 c.haraed acidic water from the first reactor to the second reactor.
[00420] The CO2 charged acidic water was then transferred from the first reactor to the second reactor. The second reactor was used for both nucleation site generation and crystal growth. After transferring the solution from the first reactor to the second reactor, the foll.ow-!n7 steps were performed:
[00421] 1. 50% NaOH was added until a pH of 9.5 was reached. For example, .for a 1000 gallon reaction, 20-25kg of 50% NaOH was added using a dosing numn capable of pum.ping 5-25m]!sec of 50% NaOH. After reaching a pH of 9.5, the addition of 50% NaOH was s!opped.

- 125 Docket No. CLRA-026WO

[0042212. A CO2 source including a mixture of 20% C02/80% compressed air was sparged into the second reactor until a pH of 8.5 was reached. After reaching a pH of 8.5, the sparging of the CO2 was stopped.
[0042313. Alternating steps of adding 50% NaOH into the reactor to raise the pH and sparging CO2 to lower the pH were performed. The pH was maintained between 8.5-9.8 during the alternate addition of the 50%
NaOH and sparging of CO2. Alternate dosing of 50% NaOH and sparging of CO2 was continued until a total of 90kg (i.e., 65-70kg in this step + 20-25kg from the first step) of 50% NaOH
was added to the reactor.
[0042414. The final pH after the last addition of 50% NaOH was between 9.6-9.8.
[0042515. Agitation was stopped and the precipitate was allowed to gravity settle overnight and then water/solids separation was performed. Alternatively, after agitation was stopped, the precipitate was allowed to gravity settle for 15 minutes and then accelerated wat r/solids senaration was performed. Precipitate was maintained at a temperatur;, below 50 C.
[004261 Resulting yields ranged from 30-50lbs of precipitate per 1000 gallon reactor and depended on Mg ion dissolution and total hardness prior to precipitation.

[004271 Example IV. COz Absorption [004281 A. Process I

[00429] In this example, absorption of carbon dioxi.de or?. the laboratory-scale is described. 4.00 L of seawater was magnetically stirred while 100% CO2 was heavily sparged through the solution for 19 minutes where the pH reached a minimum of 4.89. To this solution, 32.00 g ofjet milled Mg(OH)2 was added over a period of 2 minutes. Simultaneously, CO2 was continuously added for a total of 18 minutes to maintain a pH between 7.90 and 8.00 as Mg(OH)2 dissolved. Next, 100.00 mL of 2 M NaOH was added over a period of 5 minutes while the pH was maintained between 8.00 and 8.10 by addition of COz. To facilitate precipitation, 275 mL of 2 M NaOH was added over a period of 5 minutes and the resultant solution was stirred for an additional 52 minutes. The slurry was vacuum filtered and dried in a.i oven at .50 C for 22 hou;:-s to recover 19.5 g of calcium and magnesium carbonates (primarily aragonite and nesquehonite, respectively) per 1 L of initial seawater sohition.

[004301 B. Process 2 [004311 In this example, absorption of carbon dioxide on the laboratory-scale is described. A 100-gallon cone-bottomed plastic reaction vessel was filled with 100 gallons (380 L) of seawater, which was stirred throughout the entire process with an overhead stirrer (Portable Mixer w/Shaft, 2-4" SS Propeller Blades (1-push, 1-pull), and Mounting Frame). The first step was to sparge the solution with COz concentrated at 20%
CO2 and 80% Compressed Air, with a flow rate of 25scfh. Equilibrium was determined by the stabilization of - 1 26- Docket No. CLRA-026W0 the solution pH. The second step was to add 2.70 g/L of Mg(OH)2 (1.02 kg) with heavy mixing. To further facilitate the dissolution of Mg(OH)2, COz was sparged through the solution.
The third step was to add a solution of 50 wt% NaOH until a pH of 9.8 was reached, followed by additional CO2 sparging to lower the pH to 8Ø These last two steps of an addition of 50wt % NaOH to a pH of 9.8 and CO2 sparging to a pH of 8.0 was repeated until a total of 16.0 kg of 50wt% NaOH had been added to the solution, where the final addition of NaOH was used to reach a pH of 10Ø The precipitate was separated and collected from the solution in a yield of 10.24 g/L of calcium carbonate and magnesium carbonate hydrates.

[00432] C. Process 3 [00433] In this example, absorption of carbon dioxide on the laboratory-scale is described. A 100-gallon cone-bottomed plastic reaction vessel was filled with 100 gallons (380 L) of seawater, which was stirred throughout the entire process with ar. overhead. stirrer. The first step was to sparge the solution with CO2 concentrated at 20% by volume at a flow rate of 100 scfm (standard cubic feet per minute). Equilibrium was determined when the concentration of CO2 in the vessel headspace approached that of the inlet gas. The calculated absorption of CO2 during this step was understandably low. The second step was to slowly add 379 g of Mg(OH)2 to avoid a sharp increase in pH, which would favor the undesired carbonate precipitation. To further facilitate the dissolution of Mg(OH)2, CO? was sparged. through the solution to an end pH of 6.3. The fmal step was to continuously capture CO2 in the solution. Over the course of 3.5 hours, 4.9 kg of NaOH was added to balance the pH at 7.9 while CO2 was sparged and reacted to form bicarbonate ions. The calculated absorption of CO2 during this step was between 68% ar_d 70%. Results are provided in Fig. 44, which shows the evolution of pH and CO2 absorption (instantaneous and cumulative).
Artifacts at point l in the pH plot were from removal of the pH probe to add Mg(OH)2.

[00434] D. Process 4 [004351 In this example, absoiption of carbon dioxide on the industrial-scale is described. A 1000-.gallon reaction vessel was filled with 900 gallons (3400 L) of seawater, which was stirred th,.roughout the entire process. The first step was to load the solution with 3.3 kg Mg(OH)2, which increases both the pH and the magnesium content. Next, 10% by volume COZ Was sparged and the pH of 7.9 was maintained by a continuous addition of NaOH up to 30 kg. The total duration of these steps was 5--- 6 hours. A final charge of 38 kg NaOH was added to increase the pH so that carbonates would form and precipitate. The duration of this step was 10-20 minutes. The solution was stirred for l hour more to allow further precipitation. The reaction was allowed to settle over.night. The solution was deranted and the solid product was recovered by either filter press or vacuum filtration. Additionally, the solution could be rinsed after the decant process; whereby water was added and the sample was filter pressed. Alternatively, water was added after initial vacuum -127- Docket No. CLRA-026W0 filtration, stirred, and filtered again. Finally, the product was spray dried.
The overall yield was 5-7 g/L of the original solution.

[00436] Example V. High yield dissolution of mafic mineral in HCI

[00437] In this example, the dissolution of olivine and subsequent use to precipitate COZ is described. A
solution of 10% HCl (475.66 g) was used to dissolve olivine (10.01 g, particle size -5.8 m) at 50 C. After the solution was stirred for 1.0 hours and allowed to sit for 9 hours to provide a. Mg2+ (aq) concentration of 0.2491 mol/L, it was vacuum filtered hot to recover 404.52 g filtrate. Over the period of 1 hour, 15.01 g NaOH(s) and 5.23 g NaOH(aq) (in a 50wt% solution) were used to neutralize the solution. Simultaneously, 100% CO2 was heavily sparged through the mixture to provide a final pH of 8.9 where precipitate formed.
The slurry was vacuum filtered and dried at 50 C for 17 hours to yield 19.26 g which contained MgCO3-H2O, NaCl, an Fe-based compound and a Si-based conlpolxnd.

(00438] Example VI. Electrochemistry [00439] Exemplary results achieved i.n. accordance witli the present bi-electrode system are summarized in Table 8 below.

Table 8. Low energy electr.ochernical bi-electrode method and sys~em..

V Across Time (min) Tnitial p-H t End pH at Initial pH at End pH at Electrodes Anode Anode Cathode Cathode 0.45 V 30 4.994 5.204 7.801 7.431 0.30 V in the 1 st, and 0.15 V
in the 2nd compartment [00440] In this example, an electrochemistry system foi- de-protonating seawater that has been charged with COz is described. The cell that was used consisted of t.tiro 1-liter compartnient.s separated by a palladium foil.
The first compartment was charged with CO2 until a pIl of 4.994 was achieved.
A sacrificial tin anode was placed into the first compartment, and the tin electrode and palladium membrane were held under galvanostatic control at 100nA,/cm2, which represented a voltage of 0.30V. The second compartment consisted o.f a tin electrode and SnCl2 dissolved in seawater. The r)alladium membrane and tin electrode in the second compartment where held at 0.15V. The sy-s~:em was run for 30 ininutes and as set forth in Table 8, the system showed an increase in pH in the first electrolyte, and a decrease in pH in the second electrolyte.

-128- Docket No. CLRA-026W0 [00441] Exemplary results achieved in accordance with the ionic membrane system are summarized in Table 9 below.

Table 9. Low energy electrochemical ion exchange system and method.
V Across Time (min) 1 Initial pH at End pH at Initial pH at End pH at Electrodes Anode Anode Cathode Cathode 0.6 2000 6.7 3.8 6.8 10.8 1.0 2000 6.6 3.5 6.8 11.1 [00442] In this example, an electrocheinical cell for producing NaOH and HCI
at a low operating voltage utilizing an ion exchaxige rnexnbrane posztioned betwc,en. ~.n anode and a cathode is described. The cell that was used consisted of two 250 mL compartments that wer, sel+arated by an anionic t;xchange membrane (PC-SA-250-250 (PCT GmbH of Germany)). In both compartments 0.5M NaCI in a I SM92 aqueous solution was used. Both the anode and cathode were constructed fro: n a 10 cm x 5 cm, 45 mesh Pt gauze. The anode compartment had H2 gas sparged under the Pt electrode, and the two electrodes were held at a bias of 0.6 V
and 1.0 V for 2000 seconds. As set forth in Table 9, the two tests achieved a significant increase in the pH in the cathode compartment, and a decrease pH in the a.node compartment.

[00443] Example VII. I,iquid-Solid Separation [00444] A. Process 1 [00445] In this prophetic example, separation of precip:atation product from precipitation station effluent on the laboratory-scale is described. Precipitation product slurry is prt,nared as described above for Example IV.
[00446] Slurry comprising the precipitation product is produced in a reaction vessel (see Example IV), which, for the purpose of this example, is referred to as a precipitation station.
Following formation of precipitation product sluny, the slurry is provided to a liquid-solid separation apparatus as precipitation station effluent. A
precipitation station effluent pipe is used to provide the slurry to the liquid-solid separation apparatus and to direct slurry flow against a baffle, by which precipitation station effluent flow is deflected. Heavier precipitation product particles continue their path of motion down (i_.e., in the direction of gravity) th.e precipitation station effluent pipe to a collector while supernatant deflects, separates from precipitation product particles, and exits through the upper portion of the liquid-solid separation apparatus. The resulting precipitation product is removed from the collectoir and dried to yield of calcium carbonate and magnesium carbonate hydrates.

[00447] B. Process 2 1 29- Docket No. CLRA-026W0 [00448] In this prophetic example, separation of precipitation product from precipitation station effluent on the laboratory-scale is described. Precipitation product slurry is prepared as described above for Example IV.
[00449] Slurry comprising the precipitation product is produced in a reaction vessel (see Example IV), which, for the purpose of this example, is referred to as a precipitation station.
Following formation of precipitation product slurry, the slurry is provided as precipitation station effluent to a liquid-solid separation apparatus, wherein the slurry is made to flow in a spiral channel. At the end of the spiral channel, a parallel array of outlets collects separated particles of precipitation product. The resulting precipitation product is removed from the collector and dried to yield calcium carbonate and magnesium carbonate hydrates.

[00450] Example 1. This example shows the use of an ultrasonic atomizer to create liquid droplets of high surface area to volume ratio in one compartment, whi& are then contacted with carbon dioxide in another compartment. The system of this example resembles that of Fig. 45.
[00451] This first system used a commercial ultrasonic atomizer [Fig. 45:
200], consisting of 10 transducers, which is capable of atomizing water at approximately 4 liters per liour. A 4 inch (10.16 cm.) inline fan [located at 220] was used to move the mist of li_quid droplets [215] into a mixing compartment [245]. The gas was then recirculated from the niixing compartment [240] and back to the transducer compartment [220], while pure CO2 flowed through the system continuously [225]. Sodium bicarbonate saturated. solution that was reconstituted with 108 grams of dry NaOH pellets was used as the caustic source that was atomized.
This solution was poured into the compartment housing the transducers [205].
The pH of the mist collected in the mixing chamber [245] was taken at several tirne intervals (fini.n, l0min. 20min). It was found that the pH of the mist was always below 8, where the initial pH of the solution was above 13.5. After 20 minutes with the transducers, fan, and CO2 gas running, a precinitate of sodium bicarbonate and sodium carbonate filled the transducer chamber.

[00452] Example 2. This example employed one compartrnent for droplet generation, contacting droplets with gas, and precipitation of solid material. The apparatus of this example resembles that of Fig. 46.
[00453] This apparatus was made up of box that was 6 feet (1 F2.88 cm.) tall, 4 (121.92 cm.) feet wide, and 6 inches (15.24 cm.) deep. There was a shelf two feet (60.96 cm.) frnm the top which hous~ d a commercial 10 transducer ultrasonic unit [Fig. 46: 3001 and a fan that r;irculated g'as in a circular pattern.. The bottom of the tank was conical that allowed a precipitated slurry [350 J to flow to a storage tank [360]. The shelf [310] was filled with a 2.7N sodium hydroxide solution and was continuously filled by a recirculation pump from the storage tank [340]. Pure CO7 [370] was pumped throus;h the chamber and after several hours a sodium bicarbonate and carbonate precipitate formed on the walls of the chamber.

-13~ Docket No. CLRA-026W0 1004541 Example 3. This example demonstrates the use of recirculation and a solution of alkaline chemistry to absorb carbon dioxide gas.
[00455] This apparatus used pure COZ as the gas and consisted of a 6 inch (15.24 cm.) diameter horizontal tube that was 1.5 (45.72 cm.) feet long. A low pressure pump recirculated solution to spray nozzles which produced liquid droplets that of a much larger droplet size when compared to the droplets produced by the ultrasonic atomizer. The tube was filled with. 2.75N sodium hydroxide (NaOH), the pump was turned on atomizing the sodium hydroxide into a CO2 rich compartment. After 1 hour and 40 minutes the resulting solution contained a large a.aY?ount of precipitate Gt a r,H of 8.2, indicating sodiura bicarbonate and sodium carbonate had precipitated due to supersaturation of the solution with CO2.

[004561 Exam le 4. This ex.ample demonstrates the use of hurface area to volume ratio dro lets of tap p high _ p water to incorporate carbon dioxide gas into the clronle?s cuch.
that the droplets are nearly fully saturated with CO2 within the first 5 minutes of contact with the gas.
[00457] This apparatus consisted of an eight inch (2032 cm.) diameter tube that was forty eight inches (121.92 cm.) long with four ultrasor..ic, transducers eRurtlly spaced across the bottom. The absorber was tested using plain tap water with a starting pH of 7.8. The rii st generated by the transducers was collected after 5 minutes and tested. The pH of the bulk tap water was 6.3, and the pH of the collected mist was 5.44. The collected mist was then sparged with more CO, in a separate spart;ing system for 30 minutes and it was found that the minimum pH achievable was 5.39, so close to fizll satuxation was achieved in the first 5 minutes.
[00458] Example 5. To treat the flue gas from a 200 mega-watt power plant, it takes in 100 million gallons per day (MGD) of brines, of which 75 MGD is alkaline brine with 500 mF,q of alkalinity and 25 MGD is hard brine with a calcium concentration of 25,000 ppm. The power plant produces 200 tons/hour of carbon dioxide emission when using coal from the United States of America (i.e. the coal is not brown coal). The carbon dioxide capture rate is 90%. indicatina that 180 tons/hr of carbon dioxide is incor-oorated into the absorbing solution that is comprised of the brines listec', above. 408.6 tons of calciiun carbonate are formed per hour, which equates to about 9800 tons of product per day, once the calcium carbonate is separated from the brine and dried, and assuming continuous operatinn. of the treatment facility (i.e. emissions control system). This indicates that 0.196 pounds of procluct per gallon of brine iq produced, which equate.3 to 23.5 grams of product per liter of brine. M'hen the capture is reduced, -for example to 45% from 90%, 90 tons/hour of carbon dioxide is captured and thus 204.3 tons/hour of calcium. carbonate is formed, which equates to 0.0981b/gallon (11.75g/1). When the size of the power plant is i.ncreased, for ex.ainple from 200 mega-watts to 400 mega-watts, at 90% canture, the amount of carbon dioxide -apkured is 360 tons/hour, and thus 817.2 tons of calcium carbonate are formed per hour, corr0ating to aboiit 19,600 tons of product per day (24 hours), assuming continuous operation at stead,y-state.

"1 ~ 1 Doci<et No. CLRA-026W0 [004591 Example 6. As described herein technology has been developed for the capture of carbon dioxide and sulfur oxides from power plant flue gas. The technology is a two-part process that uses a source of base/high alkalinity material plus calcium and/or other divalent cations to capture and convert the carbon dioxide and sulfur oxides into solid carbonates and. sulfates. These solids may then be converted into end products for sale or disposal. This approach eliminates the need to separate and compress the captured carbon dioxide for geological sequestration. A demonstration plant is being used to determine the commercial-scale processing and energy requirements to remove carbon dioxide from power plant flue gas.
The demonstration plant removes carbon dioxide from a slip stream of the flue gas produced by an adjacent natural gas-fired combined-cycle power plant. The design rate of flue gas low that can be processed in the demonstration plant, approximately 20,000 standard cubic feet per miarrte ("scfm"), is equivalent to that produced. within the natural gas-fired combined-cycle power plant in generating approximately 4.0 megawatts ("MW") of power.
This flue gas flow rate is equivalent te the flue gas flm*, rate from approximately 10 MW of power from a coal-fired plant. Absorption studies have also been ccndLz.cted on coal flue gas at smaller scale in a pilot plant with the intention of blzilding another demonstration facility adjacent to a coal-fired power plant to evaluate recovery and conversion of the higher concentrations of carbon dioxide and sulfur oxides present in coal-fired flue gas. Some highlights include:
= In a test rur_, lasting a. typical two-hour steady state period with caustic and calcium chloride as the materials simulating brines with a flue gas flow rate of 12.000 scfm, a minimum of 80 percent carbon dioxide removal was achieved. Carbon dioxide removal was approximately 86 percent. Power cons.umption was 521 kilowatts ("kVV"), which is equivalent to 8.6 percent of the power produced while gPnerating thc, flue gas flow rate processed (based.
on the power generated from the equivalent coal-fired flue gas flow).
= The demonstration plant instruments and controls allow for obtaining data needed to quantify the amun.t of carbon dioxide removal obtained and intern.al power consumption required for the absorber configurations and operating conditions being tested in pursuit of goals for carbon dioxide removal and power cor_sumption.
= It should be easier to remove 80 percent of the carbon dioxide from a coal-fired flue gas initially with 15 percent carbon dioYidc (going dowrr_ to 3 perc(,.nt carbon dioxide) than it is to remove 80 nercent of the carbon dioxide from the natural gas-fired combustion turbine flue gas that initially has 4 Dercent carbon dioxide (goin? down to less than one percent).
= The demonstration plant and the sup;norting equinrnent has been. designed with sufficient flexibility in testing equipment comnrnents and operatinl; co-nditinns to allow for selecting and then cenfirming or subsecluentlv modifying promising internal configurations and operating conditions that ultimately lead to produ::in,Q the best results.
= The scale of the r.lemnstration p?ant is si~,ffciently large that any issues specifc to large'scale can be observed and connected. The demt?n.st.rati,en plant also has sufficient flexibility in the -132- Docket No. CLRA-026W0 scrubber liquid prepa.ration area to allow for testing synthe.+- c versions of the brines and base s;)urces intended to be used comir.orcially.

[00460] Demonstration Plant Process Description and Desigr~
[00461] The following is a description of the process design for the demonstration plant that is currently installed and operating. The site on which the dernonstration pla.nt is located includes facilities used in the 1940s to recover magnesium from seawater, and the demonstration site uses some of the existing large in-ground tankage on the site for the demonstration plant. A large component of the process is the absorber column ("absorber") that scrubs the flue gas to remove carbon dioxide from the flue gas by absorbing it into the scrubbing liquid slurry. The scrubbing liquid contains one or more divalent cation metals such as calcium, either dissolved or as a finely divided suspended solid. The scrubbing liquid also contains a base source of high pH such as sodium hydroxide. The flue gas leaves the natural gas-fired power plap.t at approximately 175 to 200 degrees Fahrenheit (" F"). The flue gas is transported from the natural gas-fired power plant to the demonstration plant through a 36-inch, uninsulated carbon steel pipe. Two natural gas-fired power plant flue stacks are tapped such that flue gas flow can be take.r. froni either flue stack or both simultaneously. The natural gas-fired power plant allows for the demonstration plant to take up to 24,000 scfm of flue gas with only 12 hours or less notice. This is equivalent to the flue gas produced by generating approximately 4.6 MW
of power at the natural gas-fired power plant. The flue gas enters the absorber at approximately 70 to 110 F, depending on the ambient temperature, and the flow rate of flue gas through the pipe. The flue gas pipe passes underground from the natural gas-fired power plant to the demonstration plant.
Provisions are made to collect any condensate from the cooling of the flue gas in the pipe on both. sides (i.e., both the natural gas-fired power plant side and the demonstration plant side). Condensate collected on the r:.atu.ral gas-fired power plant side is sent back to the natural gas-fired power plant. Condensate colJected on the demonstration plant's side is sent to freshwater storage for the demonstration plant.
[00462] The demonstration plant has been designed to achieve (as a goal for commercial operation) 80 percent removal of the carbon di.oxide in the flue gas taken from the natural gas-fired power plant while limiting the required power consumption to no more than 8 percent of t?ie power output represented by the production of the processed flue gas volume. Due to excess air reduiremer.ts, natural_ gas-fired combustion turbines such as those used at the natural gas-fired power plant produce more flue gas per ijnit of power production than coal-fired steam power generation. Consequently, for flue Qas aarbon dioxide rPr.aoval fo!- coal-fired utility-scale power generation, the amount of flue gas that must be processed per MW of power production may typically be less than for natural gas-fired combined-cycle power generation. Because coal contains more carbon per unit weight of fuel than nabaral gas and less flue gas is produced per unit of power output, the flue gas concentration of carbon dioxide at the absorber inlet for coal-fired power t?eneration would be higher than the carbon dioxide concentration for the natural gas-fired poix, er plant flue gas. I-Iit;her absorber inlet carbon dioxide concentration will facilitate the removal of any set percentave of carbon clioxide from flue gas.

`' 33- DooktrtNo. CLRA-026W0 [004631 The natural gas-fired power plant flue gas typically contains 3.9 to 4.2 percent by volume carbon dioxide and essentially no su]:~u oxides. A"car.bon iritensity" is assumed for a coal-fired power plant of 0.9 metric tons of carbon dioxide produced per megawatt hour ("MWh") of power production and a flue gas composition that has 15 percent by volume carbon dioxide (at approximately 6 percent excess air and saturated with respect to water at 90 F). Requirements for sulfur dioxide removal are not considered in the calculation, since none is required for the natural gas-fired power plant flue gas. The total amount of flue gas produced for the theoretical coal-fired plant while generating 10 MW was calculated. This amount of flue gas was 20,000 scfm, thus, the demonstration plant was desipi, ed to process 20,000 sefxn. The demonstration plant power consuinption goal is then to stay below 800 kW (8 percent of 10 MW) when processing 20,000 scfin.
[00464] A forced draft centrifugal fan is used to pull fllie,ga.s from t:he natural gas-fired power plant and push it through the demonstration plant. The fan uses a variable frequency drive ("VFD") to control the flue gas flow rate. A vent is provided upstream of the fan to gradually provide suction on the pipe from the natural gas-fired power plant. As flow in the pipe from. the no,irai Qas-fi.=ed power plant is established, the vent is closed. The length of pipe from the natural gas-fired power plant fluP stacks to the upstream vent is approximately 2,400 feet. There is approximately an additional 300 feet of pipe between the fan and the absorber for a total pipe run of 2,718 feet. Since most cornmercial absorbers are to be as closely coupled to the flue gas stack as possible, the fan power that is im-luded in power consumption for the demonstration plant to move the flue gas through most of this line is not counted as part of the power consumption for other facilities. The power requirement for just the absorber can also be calculated from the pressure drop across the absorber and the flue gas flow rate. The pressure drop across the ab:>orber is measured by a manometer on the flue gas inlet (the absorber exhausts to the atmosphere). The flue L~as flows to the absorber and from the absorber are measured usin.g hot wire anemometers ins,-,! ed in the turbulent flow.
[00465] In the demonstration plant, it is intended to use rhemicals representative of naturally occurring hard and alkaline brines that are tn be used in commercial operations. These include, but are not limited to calcium chloride, calcium hydroxide, sodium hydroxide, sodiu-i1 chloride, sodium carbonate and sodium borate.
Power plant fly ash (that is both a source of cations and base) may also be used for part of'the scnibbing reagent requirement. Currentl.y, calcium hydroxide and/or calcium chloride is being used as the divalent cation source, sodium hydroxide and/or calcium hydroxide as the hase source, and either freshwater or seawater to form the absorbing liquid used in th.e demonstration nlart absorber. 'I'he calcium hydroxide is representative of hydrated calci.um oxi.de ("CaO") in f7v ash or cement kiln diast and has been used to start up and initially operate the demonstration plant. Calcium chloride is being used to model the calcium hardness in the brines expected to be used for conrmercial opervi-ion. It is intende:l to expand the chemicals used to include sodium carbonate and. other compounds found in subsurface water reservoirs. These chemicals will be tested to determine their ability to promote desired properties in the dewatered sotids (from the net slurry recovered from the absorber) for ma?cing byproducts.

-114- Docket No. CLRA-026W0 [00466] For the start up and commissioning of the ilemonstration plant, calcium hydroxide was used. Solid calcium hydroxide (93.5 percent purity with the balance being mainly calciuni carbonate) is delivered by truck to the demonstration plant site. The calcium h.rdr,)xide is niixed with fresh water and/or seawater in the 120,000 gallon capacity base mixing sump that is an existing outdoor open tank at the site. The capability to add supernatant (the water phase from the Epuramat solids-=water separator (the "l7puramat") that is described below) is to be installed at a later date. Seawater is stzpplied from an existing harbor pump that feeds the seawater storage tank with a capacity of approximately 1,000,000 gallons. The stored seawater is pumped through sand filters to remove particulate and organic soiids before use to reduce the risk of fouling. The liquid in the base mixing sump is ci..rculated through a. turbolizer that combines the solid calcium hydroxide with the slurry in the slimp. Agitators and pumps ar-. used to keep the slurry well mixed. The slurry is then pumped to the base mixing tank. The base mixing t!~nk is an existing outdoor open tank at the facility with a capacity of 140,000 gallons. Agitators are used to kceo the c,ontenis of the tar_k w2ll mixed. In the base mixing tank, liquid (currently filtered seawater, but also evr;ntually supernatant) can be added to maintain the weight content of the calcium hydroxide slurry at approximately 6 weight percent ealcii..im hydroxide solids.
The slurry solids content is monitored by taking grab samples f;om_ the tank and measuring for total solids.
Slurry is pumped frotn the base mixing tank to the 10,(00 aall.on capacity base surge tank.
[00467] When used, liquid cpAcium chloride solution is recPived by truck. The base preparation system is also used for this cation sot!rce processing. The calcium c'H:)ride solutior. is stored in the base mixing sump. It is then diluted in the base mixing tank. Calcium chl.ondea.rci wa Fr are simultaneously pumped into the base mixing tank. The diluted ca'ciurn chloride is then ~)urnpe!i to the base surge tank. The dilu.t,-d calcium chloride is pumped to the slurry feed pipe headers for the aprzro,,)riate/selected levels of the absorber.
[00468] Dilute sodium hydroxide is fed to the base surge tank from one of the two caustic dihition tanks to provide a source of base for the absorption of carbon &ox.ide. The dilute sodium hydroxide solution is made by combining 50 weight percent sodium hydroxide solu.tion (that is stored in two 10,000 gallon capacity tanks) with fresh water in one of the caustic dilution tanks. "The contents of the base surge tank are pumped through the absorber feed pump to the absorber. Dilute sodium hydroxide can also be pumned directly to any of the six pipe headers that feed slurn,l to the absorber.
[00469] Between operating runs the contents of the base tnixinc, su.m>> are seni to the base mixing tank, and the base mixing sump is flushed out with either fresh or sea water. The flushings are sent to the TI slurry storage tank that is currently being used to store the nF:t absorber product slurry. Because the contents of the base mixing tank can pick up carbon dioxide from snray contact with. air, the contents of the base mixing tank are also emptied between nzns into the Tl slurry stcra;=e tar~t, either directly or through the absorber.
[00470] The flue gas enters the absorber below tr.e scrubbia _? stage; and above the liquid collect:ion sump. The flue gases flow upward throul;h the absorber past six levels or stages in the absorber (numbered in ascending order from the bottom level) at which fresh and recit-ciilated scrubbing liquid can be injected and internals can be installed (using periphe.ral support rings attached to the absorber internal diameter). The scrubbing liquid - 135- Docket No. CLRA-026W0 flows down the absorber by gravity from its injection pont:(s). After passing upward through the scrubbing stages, the flue gas then passes through a liquid demister (a vapor-liquid separator that removes the entrained liquid by impingement) and out of the top of the absorber to the atmosphere.
No reheat of the flue gas is required. Exhaust of the flue gas to the environment is per-rnitted after :he absorber at the absorber outlet temperature. Gas sampling for the flue gas to measffe carbon dioxide concentration occurs above the demister and just before the entrance to the absorber. 'The standard method of carbon dioxide measurement is through the continuous emission monitoring system_ ("CEMS") that uses two different analytic devices. The Thermo Environmental Model 60i is used as the primarv measureinent with the Sen-omex 1440D Gas Analyzer used as backup and as a crosscheck. Gas saniples can als:~ be taken inanually for laboratory analysis.
[00471] Absorber internals comprise shedrows at the f.irst level. The shc.drow,: (inverted ar,gle iron) extend across the diameter of the absorber, perpendicular to the flue gas flow and attach to the support rings on the absorber shell. Each absorberr level has five headers that are perpPndicular to the flue gas flow that can be used to attach sprav nozzles. Pressure drop across tl-!e rozzles is ?r,easured. The linuid from the scrubbing accumulates in the liquid collection sump. Liquid is rcc;i~-culated from the bottom of the absorber to one or more stages through three parallel recirculation punws. To avoid butild-up of liquid in the absorber, a purge stream whose flow is controlled by the liquid sump lev~l is remo-r?4 from the recirculating scrubber liquid and is sent to the absorber product surge tank. Thc ~Absarb,;r pr3duct transfer pump is to be used to move the product slurry to the Fpurarnat vessel where the shirry is to he dewatered from approximately 5 to 7 weight percent solids to 20 to 40 weight percent solids, fnr-miniJ a. liquid supernatant and a tliickened slurry. The Epuramat is designed to receive input flows pumpei to the top of the vessel jvhere the slu.mr then flows under gravity down a central feed pipe and exits into the an.ri!lar region via an adiu,table diffixser/separator located towards the bottom of the unit. The diffuser is designed to indlace a.
transition from turbulent to laminar flow whereby the solid materia.l s~:parates under a shear gradient, resulting in the supernatant and thickened slurry streams.
[00472] The Epuramat is installed ard currently heing coanmiss.ored.
Currently, ~he contents of the absorber product surge tank are sent tn the outdoor TI slurrv opnn storage tank that has acapacity of 2,500,000 gallons and is used to separate the sl-.rrry solids from the liq(iid by gra-ity. Once the f;puramat is operating, the dewatered slurry from the Tntiramat is to be sent to the Ti sh:rry storage tank, and tiie liquid supernatant is to be sent to the supernatant st?rge tank. The supernatant i. " , to be pum.*)ed out of tl-ie cupernatant surge tank to the 2,500,000 gallon outdoor T4 open supernatant storage, `a k. The ri.ine;rnatant is to be rer,yclecl to the base mixing sump to reduce process water consumption and to utilize unreacted base and alkali.
[00473] Currently, to control the level in the Tl ;;lurry s.toratTe tank, the supernatant liquid in the top of the tank from the settled absorber slurry purge is ch(eked 1)r pH and is dis(.l).a.rged under permit. Recirculation of the liquids in the process may reduce or possibly eliminate the need to discharge any liquid from the process.
If the pH is too high and needs ad?ustment, carbon dioxi:A:tiis added bv bubbling it through the liquid to make the liquid less basic (lower pH) and suitable for dise:harge, Some of the solid.s accumulating in the T1 slurry ~ S~?- 'Pocket No. CLRA-026WO

storage tank are to be used for making and evaluating products from the dewatered solids in other equipment that is located on site. Once the Epuramat is operating, excess svipenaat,ant from the d.enionstration plant can be discharged from the T4 tank to the bay (with carbon dioxide addition as necessary for pH adjustment).
[00474] In addition to testing absorber slurry dewateri_ng with the Epuramat that is designed to take the full absorber purge flow, the intent is to test four to six other slurt}, dewatering systems on a smaller scale with vendor supplied pilot plants. The slurry flows to these pilot plants are to be provided from the absorber product surge tank.
[00475] After dewatering, the intent is to test equipment for additional d.ewatering and processing of the thickened slurry to evaluate what end products can be pi-oduced frDtn the absorber solids.
1004761 All of the major pum.ps in the demonstration plant use VFDs. The liquid flow rates are measured by the pump speed and by magnetic fl,-.)w meters. The flows to absorber levels 4.
5, anc16 are measured with magnetic flow meters. Current.l,v, there are no installed magnetic floixi meters for levels 1, 2, and 3; other level flow meters are repositioned from other levels when m~astuements from levels 1, 2, or 3 are needed. Flow meters for the flow to levels 1 through 3 will be installed over the next several weeks. The measured pressure drop across the nozzles and the theoretical flow rate(s) for the nozzle design is also used to monitor for nozzle plugging, by comparing the theoretical flow `vith the actual flows.
[00477] To shutdown the operation of the absorber (or to flush it "c?ean"), the flow of flne gas from the natural gas-fired power plant is halted, fresh scr bbint- solution flrnv is stopped, and scrubbing solution recycle is stopped, Then, fresh water from the spray water storage tank i.s pumped into the top of the absorber through nozzles located below the mist eliminator. `[7ie spray water can also be directed into nozzles above the mist eliminator, as required, to clean it.

[00478] Demonstration Plant Design and Operation [00479] To evaluate and optimize carbon dioxide absorption and power consumption, the following engineering design parameters are provided:
= Location and num.ber of liquid iniection points = L?'.quid spray patterns and droplet sizv range and nozzle pressure drop = Liquid spray rates relative to the gas flow rates = Internals for mixing and mass transfer = Gas residence tinle in the liquid srray [00480] The concentrations ef the base and alkali fcf;ds to 11ie N ~,~cess r.nay also be a,;ljt:sted by adding water at the caustic dilution tanks and feed liquid storage tanks, respectively.
Subject to any current design limits on pumping or flue gas fan capacity, the ability to e~;p;~rirr!er~t with and modify these parameters should allow for identifying the "best" eqtiiptnent arrangements an.d c;l~cratir:g c=-)-Oi*.ioi~s towards achieving carbon dioxide removal and power consumption goa's. The size (d'arc. ter) of the absorber is sufficient to avoid wall effects and to observe (and then resolve) any issues with poor distribution of the flue gas or scrubbing liquid that -137- Docket No. CLRA-026W0 might occur while testing int.ernals. Sonie of the valving (mainly used as on/off valves to set up and direct different configurations of scrubber ?;qu.id flow) is tna.nua'ly operatc,d as tests c,on+inue to improve operability and maintainability.
[00481] As described above, two continuous flue gas carbon dioxide and oxy~~en concentration monitoring devices are used in parallel to measure absorber carbon. dioxide removal as a function of the operating conditions and equipment configuration. These instruments can be checked on line by switching to an ambient atmosphere feed, and are calibrated at the start of the runs for each day against a gas standard.
[00482] In addition to the C EMS data, other recorded date includes, but is not limited to pH, gas flow rates, liquid flow rates, pressures, tPrnperatlires and percent solids. For n^1r_ual sampling, of gases, liquids, and slurries, a methodology for cliain of control and data handling is followed.
[00483] To monitor power consumption, VFD drive power inputs to all pumps and the flue gas fan are monitored. The electric meter reading that is used for the official power consumntion is also monitored. The difference between the sum of the VFD power usage anc! the electric meter reading is attributable to lights, agitators, instrumentation, control systems, and other demonstration plant loads. The magnitude of these loads would tend to decrease in a fiill==scale facility, relative to the major rnotor loads that are listed in Table 1.
Consequently, the electric meter reading is a conservativc, value to use. In.
addition, the power requirements attributable to the flue gas induce draft ("ID") fan. would be expected to decrease relatively proportionately in a full-scale facility assuming the absorption unit was close coupled to the plant flue gas stack.

Table 1. Demonstration Plant Major Power Loads Item Loa.d(lff) Flue gas ID fan 25 Recirc Pump A 192 Recirc Pump B 195 ~

Recirc Pump C '78 (c~'c.uiated) All Transfer Pumps 14 Total from VFDs 505 (ittcl Pump C) Other Loads (by difference) ! 6 Total from Meter Epuramat (not running) (estimated) Total Note: Loads froni Febzuary 23,2010 run at 12,000 scfr, arid fi ?; 1--A=
c>nrec:~.-:1e pumps [00484] After establishing flue gas flow rates and liqui<l dow rit:e~,, for a nva, tile demonstration plant is put into steady state operation (no fluctuation in liqtiid i7.ou, 2r3lloos per minute or flue gas acfm). Steady state is 1 ~- Docket No. C:LRA-026W0 usually established in less than an hour. Once steady state is obtained, a nin officially starts with respect to data collection. Typically, after obtaining data for an lamr or two, operating conditions are changed so that a different set of run condition can be tested. Testing per:odc~ encompassing several runs have typically been in the range of 12 to 20 hours duration.

[00485] Test Data [00486] Complete data on at least two runs has been collected. The differences between the two runs were the levels (flow rates) of fresh brine and sodium hydroxide (caustic) f: ec'..
Both n.,ns met a minimum 80 percent carbon dioxide removal. However, the run with the higher levels of fresh brine and caustic feed was above the goal of 8 percent power consum.ption. The run with the lower levels of fresh brine and caustic feed approached the goal of 8 percent power consumption (521 kW at the flue gas flow rate used that is equivalent to 8.6 percent). This run used calcium chloride as the cation material, sodium hydroxide as the base material and the flue gas flow rate was 12,000 scfm. The absorber recycle pumps were operating at full capacity.
Carbon dioxide removal was approximately 86 percent Riin. parameters are still being evaluated.
[00487] If one theoretically increases the flue gas flow to the design flow of 20,000 scfm while retaining the other specific run conditions, the overall power usage would be expected. to be slightly higher (approximately 44 kW) due to the increase in flue gas fan power required (about 175 percent more, because fan power is proportional to the square of the flue gas flow). but the power consumption value would be lower (dropping from 8.6 percent to approximately 5.6 percent) becausF the additional flue gas represents 67 percent more coal-fired power generation. Carbon dioxide removal is exoected to decrease due to the lower available unit of scrubbing liquid per unit of gas. The actual carbon dioxide removal would need to be determined experimentally.

[00488] Observations [00489] Foaming has been observed in the absorber. The foanming has been controlled by impingement plates installed in the liquid sump.

[00490] When calcium chloride ("CaCI,") is used as thc cation soti-rce to remove the carbon dioxide ("C02") and sodium hydroxide ("NaOH") is used as the high pI-[ base source, sodium chlo-ide (NaCI) is formed along with the water ("H20") and calcium carbonate ("CaCO,") that are formed:

[00491] CaC12 + CO2 + 2NaOH --> CaCO3 +2NaC1 + H2O

[00492] The calcium carbonate is removed as a solid by the mechanical dewatering of the scrubber liquid (i.e., in the Epuramat or other equipment). To avoid a build-up of sodium chloride from the recycling of the supematant, it must be purged from the system. Since so;liu.rn chlor%de is highly snluble, it can be removed with water during the mechanical dewatering step a: residiaal liquid with the dewatered solids. Consideration - 13y- Docket No. CLRA-026W0 is being given to add this process by the implementation of a rinsing step and/or by particle size separation during drying. It has been determined that the sodium chloride fonns very small evaporite crystals which can be removed from larger particles in the spray dryer.
[00493] Carbon dioxide removal is being performed at temperatures that are below typical power plant stack gas temperatures. The absorption of carbon dioxide is enhanced by lower temperatures. The lower temperature also reduces the volumetric gas flow that must be processed. It is intended to operate commercial absorbers within the approximate temperature range beirg tested in the demonstration plant. It is intended to use the sensible heat froni the cooling of the power plaTit stack gas to be processed in drying the dewatered solids. The processed flue gas may, in some embodiments, be rebeated to provide additional buoyancy to vertically disperse the flue gas (e.g., to avoid ground level fog formation from condensation). Reheat capability may be available at existing power plants in the sulfur oxides sr,nzbbing system.
[00494] The rate at which carbon dioxide can be absorbed into the scrubbing liquid is mass transfer limited.
Based on laboratory and pilot plant data, it has been concluded tha,t_ the major resistance is getting the carbon dioxide (from the flue gas) across the liquid side bounda.nj laver of the liquid droplet. Thus, the rate and amount of carbon dioxide that can be absorbed is proportional to the surface area of the liquid (or sh.ury) droplets. More surface area provides more avenues for ahsomtion, especially if the rate of absorption is constant. The amount of droplet stirfac.e area is a fi.inctaon of the droplet size (smaller droplets have more surface per unit volume) and the total number of droplets or liqtiid volume used. In practical terms, the amount of liquid used is exprcssed as apm (of slurry) per 1.000 scfzn of flue gas (the "L/G" ratio). A higher L/G will remove more carlion dioxide than a lower I,/G, õ if all other operating parameters are held constant.
The amount or percentage of carbon dioxide removed can also be increased by increasing the flue gas residence time (exposure time to liquid droplets) in the absorber. Each of these options has a related cost.
Increasing the L/G increases the amount of power nPede-A to pump the additional liquid slurry. Decreasing the slurry droplet size also increases the power consumption for the process because more energy is required to make smaller droplets (and to make smaller solid particles for the slurry).
Increasing absorber residence time increases the size (and cost) of the absorber. Diff.er?nt confiÃn.lrati.ons of r sidenee time, spraying designs, liquid flow rates, and internals will be tested to establish t~ze desi_gn nara.meters for the commercial scale absorber.
[00495] Mass transfer of carbon dioxide also depend,, on the relat-ve concentrations of carbon dioxide in the flue gas and in the liquid. Because the absorbed cnrbor d_ioxide gas reacts within. the scnibbing liquid to form calcium carbonate solid, one can assume that the carbon dioxide concentration in the liquici is always very low, approaching zero. Thus, higher concentrations of carbon dioxide in the flue gas will increase the rate of transfer of carbon dioxide into the liquid. Conseduently, :i+ Is easier to rem.ove 80 percent of the caxbon dioxide from a coat-,fired flue gas initially with 15 herc.ew carbon dioxide (coing down to 3 percent carbon dioxide) than it is to remove 80 percent of the carbon dioxide from a natural gas-fired combustion turbine flue gas that initially has 4 pereent carbon dioxide (goinl; dowz: to less than 1 percent). This phenomenon. validates 1 -40- Docket No. CLRA-026W0 the assumption that it should be possible to remove 80 nercent of Lhe carbon c:ioxl.de from the natural gas-fired power plant flue gas voltime equivalent to up to 10 i?,!1W of coal-fired power plant flue gas with less than the amount of power it would actually take to remove 80 percent of the carbon dioxide from the coal-fired flue gas.
1004961 Tests with the coal-fired pilot plant mentione; above have been continuously performed. Based on the multi-pollutant testing in the pilot plant absorption process on coal flue gas, the process:
= Removes most trace metal emissions to non-detect levels usirig US EPA
reference methods;
= Captures mercury at L-i-eate,r than Rt? p;rcent rQmova.l ef icie*.:.cy (deper.der..*. upon the coal type fr%x?);
= Captures hi ;:-r levels of acid gas by T; .e ob 3CrV::d rapture rate were >99 percent S02; >88 percent S03, and >81 percent HCI; and.
= All tra;:e , lu-zents assayed in the sz,;~_~ ~:r~rzt 11r-Ji7i dc:wateri:rt;
were beho~cv water discharge limits (US: Y'' DES) 1004971 These saine results can be realized as the prDcess is scau'nd up on coal-fired plants.
[00498) While the invention ha; beQn. described in tc3-ms cif various embodiments, and while these embodiments have been described in oonsidera.ble c?nt-~il, not the. intention of the inventors +.o restrict or in any way limit the scope of the invention to such detail. It should be apparent to those of ordinary skill in the art that various adaptations a,nd. modi.fications of the im,erqti.on n?ay be accomplished wit.hout departing from the spirit and the scope of the. inv ntion. The foregoin6 are merely examples of variations that may be ' employed, and additional advanta.ges and modifica.tions will readi!y appear to th.ose, af ordinary skill in the art.
Thus, the invention in its broader aspects is therefort-, not limited to the specific details, representative embodiments, and illustrative exanlples shown and described. Accordingly, depar-tures may be made from such details without departing from the spirit or- scope of t.he general inventive concept. Accordingly, it is to be understood that the detailed description and the accomranyin; draivings as set forth herein are not intended to limit the breadth of the invention. whi'ch sho>>l.d he inferred only from the following claims and their appropriately construed leQal equivalents.

-141- Docket No. CLRA-026w0

Claims (64)

1. An apparatus for transferring a component of a gas into a liquid, said apparatus comprising:
a gas inlet;
a chamber configured to contact the liquid and gas:
a first liquid introduction unit at a first location within the chamber and a second liquid introduction unit at a second location within the chamber, wherein the liquid introduction units are configured to introduce the liquid into the chamber for contact with the gas:
a reservoir configured to contain the liquid after it has contacted the gas;
an outlet for the liquid after it has contacted the gas, wherein the inlet, the chamber, the liquid introduction units, the reservoir, and the outlet are operably connected; and at least one of the following features:
i) at least one array of shed rows within the chamber, wherein the shed rows are configured to redistribute the flow of the gas as it enters the chamber such that the gas flows axially along the chamber over a greater area of the cross section of the chamber than the gas flow upon entering the chamber, prior to interacting with the shed rows;
ii) an anti-foaming device configured to reduce foaming in the reservoir;
iii) at least one pump per liquid introduction unit for pumping the liquid through the introduction unit;
iv) configuration of the liquid introduction units such that the direction of the flow of the liquid out of the first unit is different than the direction of flow of the liquid out of the second unit;
v) one or more restriction orifice mechanism (release valve) configured to direct liquid flow to at least one of the liquid introduction units, into the gas inlet, or a combination thereof; and vi) varying the area covered by the liquid introduction units, wherein the liquid introduction units comprise atomizing units that create sprays, wherein at least one atomizing unit is configured to create a spray of angle different from that of the other atomizing units.

2. The apparatus of claim 1 comprising at least two of the features.

3. The apparatus of claim 2 comprising at least three of the features.

4. The apparatus of claim 3 comprising at least four of the features.

5. The apparatus of claim 4 comprising at least five of the features.

6. The apparatus of claim 5 comprising all of the features.

7. The apparatus of any of claims 1-6, wherein the gas inlet is configured to accept industrial waste gas, compressed ambient air, compressed carbon dioxide, super critical carbon dioxide or any combination thereof.

8. The apparatus of any of claims 1-6, wherein the gas comprises an industrial waste gas, carbon dioxide that has been previously separated from an industrial waste gas, or any combination thereof.

9. The apparatus of claim 8, wherein the gas comprises one or more of carbon dioxide, nitrogen oxide, and sulfur oxide.

10. The apparatus of any of claims 1-9, wherein the first liquid introduction unit is located on the lowest level above the inlet of the gas and is oriented to direct the flow of liquid into the chamber in a direction substantially co-current to the direction of gas flow.

11. The apparatus of claim 10, wherein the second liquid introduction unit is oriented to direct the flow of liquid into the chamber in a direction substantially countercurrent to the direction of gas flow.

12. The apparatus of claim 11, wherein first liquid introduction unit, the second liquid introduction unit, or both comprise nozzles.

13. The apparatus of claim 12, wherein the nozzles comprise dual-fluid nozzles.

14. The apparatus of claim 12, wherein the nozzles comprise eductor jet nozzles.

15. The apparatus of claim any of claims 1-14, wherein at least one of the pumps is controlled with a variable frequency drive.

16. The apparatus of claim 10, wherein the anti-foaming device comprises a cone situated over the reservoir.

17. The apparatus of claim 10, wherein the anti-foaming device further comprises liquid sprays oriented towards the cone.

18. The apparatus of claim 10, further comprising a liquid recirculation circuit configured to direct the liquid from the reservoir to the one or more of the liquid introduction units.

19. The apparatus of either claim 10 or claim 18, further comprising a demisting level before the gas exits the contacting chamber.

20. The apparatus of claim 19, wherein the demisting level comprises a chevron demister, flat-jet sprays, a wet electrostatic precipitator, a packed bed, or any combination thereof.

21. The apparatus of claim 19, wherein the liquid provided to the demisting level comprises a different solution from the liquid provided to the liquid introduction units.

22. The apparatus of claim 21, wherein the liquid provided to each of the liquid introduction units comprises a different solution.

23. The apparatus of claim 21, wherein the liquid provided to the demisting level is a clear liquid.

24. The apparatus of claim 21. wherein the liquid provided to the liquid introduction units comprises a slurry.

25. The apparatus of claim 24, further comprising a comminution station configured to accept slurry from the reservoir and provide processed slurry to the liquid introduction units.

26. The apparatus of claim 25, wherein the recirculation circuit comprises the comminution station.

27. The apparatus of any of claims 1-26, wherein the reservoir is located below the nozzles at the bottom of the contacting chamber.

28. The apparatus of any of claims 1-26, further comprising a precipitation tank operably connected to the contacting chamber.

29. The apparatus of claim 28, wherein the precipitation tank comprises temperature controllers, inlets for addition of pH adjusting agents, agitators, inlets for crystal growth agents, inlets for crystal seeding agents, inlets for settling agents, inlets for flocculants, or any combination thereof.

30. The apparatus of claim 29, further comprising a precipitate outlet operably connected to the precipitation tank.

31. The apparatus of claim 30, wherein the precipitate outlet collects a solid precipitate and a supernatant solution.

32. The apparatus of claim 31, wherein the precipitate outlet separates solid precipitate from the supernatant solution.

33. The apparatus of claim 32, further comprising a conduit to provide the solid precipitate to a building materials fabrication station.

34. The apparatus of claim 33, wherein the gas inlet is configured to accept a waste gas from an industrial plant.

35. The apparatus of claim 34, wherein the gas inlet is configured to accept a flue gas from a plant that combusts fossil fuel.

36. The apparatus of claim 35, wherein the gas inlet is configured to accept a flue gas from a plant that combusts fossil fuel, further wherein the flue gas has passed through an emission control system prior to being provided to the gas inlet of said apparatus.

37. The apparatus of claim 36, wherein the emission control system comprises one or more of the following:
i) an electrostatic precipitator to collect particulates;
ii) SOx control technology;
iii)NOx control technology:
iv) physical filtering technology to collect particulates;
v) mercury control technology.

38. The apparatus of claim 7, wherein the sprays of the atomizing units comprise sprays of 60° near the walls of the contacting chamber and sprays of 90° in the inner cross section of the contacting chamber.

39. The apparatus of claim 7, wherein the flow of the gas across the shed rows is perpendicular.

40. The apparatus of claim 7, further comprising packing material, trays, a packed bed, or any combination thereof within said chamber.

41. The apparatus of claim 40, further comprising a at least one membrane or one microporous membrane within said chamber.

42. An apparatus comprising:
an absorber comprising a bubble column;
an inlet for an industrial gas, wherein the industrial gas comprises CO2, SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash in an amount equal to a time-averaged original composition, operably connected to the absorber;
an inlet for an absorbing solution, wherein the absorbing solution comprises an alkaline solution comprising a salt water, particulate material, or both in an absorbing slurry;
an outlet for an effluent gas, said gas characterized by being depleted in CO2 and at least one of SOx, NOx, heavy metal, non-CO, acid gas and/or fly ash relative to said original composition of said industrial gas, wherein the outlet is operably connected to said absorber;
an outlet for absorbing solution that has contacted the industrial gas operably connected to the absorber; and a processing station operably connected to the output, wherein the processing station is configured to obtain at least one of the following saleable products: a building material comprising a CO2 sequestering component, a desalinated water, a potable water, a slurry comprising a CO? sequestering component, or a solution comprising a CO2 sequestering component, wherein the bubble column is configured to produce bubbles of the industrial gas within the absorbing solution such that at least 10% by weight of the carbon dioxide in the industrial gas is transferred to the absorbing solution.

43. An apparatus comprising:
an absorber comprising a sparging vessel;
an inlet for an industrial gas, wherein the industrial gas comprises CO2, SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash in an amount equal to a time-averaged original composition, operably connected to the absorber;
an inlet for an absorbing solution, wherein the absorbing solution comprises an alkaline solution comprising a salt water, particulate material, or both in an absorbing slurry;
an outlet for an effluent gas, said gas characterized by being depleted in CO2 and at least one of SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash relative to said original composition of said industrial gas, wherein the outlet is operably connected to said absorber;

an outlet for absorbing solution that has contacted the industrial gas operably connected to the absorber; and a processing station operably connected to the output, wherein the processing station is configured to obtain at least one of the following saleable products: a building material comprising a CO2 sequestering component, a desalinated water, a potable water, a slurry comprising a CO2 sequestering component, or a solution comprising a CO2 sequestering component, wherein the sparging vessel is configured to produce bubbles of the industrial gas within the absorbing solution such that at least 10% by weight of the carbon dioxide in the industrial gas is transferred to the absorbing solution.

44. An apparatus comprising:
an absorber comprising a spray tower;
an inlet for an industrial gas, wherein the industrial gas comprises CO2, SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash in an amount equal to a time-averaged original composition, operably connected to the absorber;
an inlet for an absorbing solution, wherein the absorbing solution comprises an alkaline solution, particulate material, or both in an absorbing slurry;
an outlet for an effluent gas, said gas characterized by being depleted in CO2 and at least one of SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash relative to said original composition of said industrial gas, wherein the outlet is operably connected to said absorber;
an outlet for absorbing solution that has contacted the industrial gas operably connected to the absorber; and a processing station operably connected to the output, wherein the processing station is configured to obtain at least one of the following saleable products: a building material comprising a CO2 sequestering component, a desalinated water, a potable water, a slurry comprising a CO2 sequestering component, or a solution comprising a CO2 sequestering component, wherein the spray tower is configured to produce streams, droplets, or a combination thereof of the absorbing solution in the industrial gas such that at least 10% by weight of the carbon dioxide in the industrial gas is transferred to the absorbing solution, further wherein the spray tower is configured to operate at a liquid flow rate to gas flow rate ratio (L/G ratio) of between 50 and 5,000 gallons per minute/1000 actual cubic feet.

45. An apparatus comprising:
an absorber comprising a at least one of a spray tower, packing material, a packed bed, trays, shed rows, or a microporous membrane;

an inlet for an industrial gas, wherein the industrial gas comprises CO2, SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash in an amount equal to a time-averaged original composition, operably connected to the absorber;
an inlet for an absorbing solution, wherein the absorbing solution comprises an alkaline solution, particulate material, or both in an absorbing slurry;
an outlet for an effluent gas, said gas characterized by being depleted in CO2 and at least one of SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash relative to said orignal composition of said industrial gas, wherein the outlet is operably connected to said absorber;
an outlet for absorbing solution that has contacted the industrial gas operably connected to the absorber; and a processing station operably connected to the output, wherein the processing station is configured to obtain at least one of the following saleable products: a building material comprising a CO2 sequestering component, a desalinated water, a potable water, a slurry comprising a CO2 sequestering component, or a solution comprising a CO2 sequestering component, wherein the absorber is configured to produce streams, droplets, or a combination thereof of the absorbing solution in the industrial gas such that at least 10% by weight of the carbon dioxide in the industrial gas is transferred to the absorbing solution, and further wherein the absorber is configured to operate at a liquid flow rate to gas flow rate ratio (L/G ratio) of between 50 and 5,000 gallons per minute/1000 actual cubic feet

46. An apparatus comprising:
an absorber comprising a at least one of a spray tower, packing material, a packed bed, trays, shed rows, or a microporous membrane;
an inlet for an industrial gas, wherein the industrial gas comprises CO2, SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash in an amount equal to a time-averaged original composition, operably connected to the absorber;
an inlet for an absorbing solution, wherein the absorbing solution comprises an alkaline solution, particulate material, or both in an absorbing slurry, wherein said alkaline solution comprises a salt water, a clear solution, or any combination thereof:
an outlet for an effluent gas, said gas characterized by being depleted in CO2 and at least one of SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash relative to said original composition of said industrial gas, wherein the outlet is operably connected to said absorber;
an outlet for absorbing solution that has contacted the industrial gas operably connected to the absorber; and a processing station operably connected to the output, wherein the processing station is configured to obtain at least one of the following saleable products: a building material comprising a CO2 sequestering component, a desalinated water, a potable water, a slurry comprising a CO2 sequestering component, or a solution comprising a CO2 sequestering component, wherein the absorber is configured to produce streams, droplets, or a combination thereof of the absorbing solution in the industrial gas such that at least 10% by weight of the carbon dioxide in the industrial gas is transferred to the absorbing solution.

47. An apparatus comprising:
an absorber comprising a at least one of a spray tower, packing material, a packed bed, trays, shed rows, or a microporous membrane;
an inlet for an industrial gas, wherein the industrial gas comprises CO2, SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash in an amount equal to a time-averaged original composition, operably connected to the absorber;
an inlet for an absorbing solution, wherein the absorbing solution comprises an alkaline solution, particulate material, or both in an absorbing slurry, wherein said alkaline solution comprises a salt water;

an outlet for an effluent gas, said gas characterized by being depleted in CO2 and at least one of SOx, NOx, heavy metal, non-CO2 acid gas, and/or fly ash relative to said original composition of said industrial gas, wherein the outlet is operably connected to said absorber;
an outlet for absorbing solution that has contacted the industrial gas operably connected to the absorber; and a processing station operably connected to the output, wherein the processing station is configured to obtain a saleable product, wherein the absorber is configured to produce streams, droplets, or a combination thereof of the absorbing solution in the industrial gas such that at least 10% by weight of the carbon dioxide in the industrial gas is transferred to the absorbing solution.

48. The apparatus of any of claims 42-47, wherein the inlet for an industrial gas is configured to accept industrial waste gas, combustion flue gas, cement kiln flue gas, compressed carbon dioxide, super critical carbon dioxide, or any combination thereof.

49. The apparatus of any of claim 48, wherein the absorbing solution is contacted with the industrial gas such that the absorbing solution is present as droplets, rivulets, columns of liquid, jet sprays, liquid sheets, neutrally buoyant clouds of solution, or any combination thereof.

50. The apparatus of claim 49, further comprising atomizing components, comprising: pressure atomizers (nozzles), rotary atomizers, air-assisted atomizers, airblast atomizers, ultrasonic atomizers, ink jet atomizers, MEMS atomizers, electrostatic spray atomizers, dual fluid atomizers, eduction nozzles, or any combination thereof within the contacting chamber.

51. The apparatus of claim 48, wherein the salt water in absorbing solution comprises sea water, an alkaline brine, a cation rich brine, a synthetic brine, an industrial waste water, an industrial waste brine, or any combination thereof.

52. The apparatus of any of claims 42-51: further comprising a recirculation system.

53. The apparatus of claim 52, wherein the recirculation system comprises conduits and pumps to move absorbing solution that has contacted the industrial gas from the outlet for absorbing solution that has contacted the industrial gas, the processing station or both to the inlet for absorbing solution, the atomizing components, or any combination thereof.

54. The apparatus of claim 53, wherein the recirculation system comprises conduits and pumps to move gas reduced in CO2 from the outlet for effluent gas to the inlet for industrial gas, the bubble columns, sparging vessel, or any combination thereof.

55. An emissions control system operably connected to a power plant wherein the power plant produces energy and an industrial waste gas comprising carbon dioxide, wherein the emissions control system is configured to absorb at least 50% of the carbon dioxide from the waste gas and is configured to use less than 30% of the energy generated by the power plant.

56. An emissions control system operably connected to a power plant wherein the power plant produces energy and an industrial waste gas comprising oxides of sulfur, wherein the emissions control system is configured to absorb at least 90% of the oxides of sulfur from the waste gas and is configured to use less than 30% of the energy generated by the power plant.

57. An emissions control system operably connected to a power plant wherein the power plant produces energy and an industrial waste gas comprising carbon dioxide and sulfur oxide, wherein the emissions control system is configured to absorb at least 50% of the carbon dioxide and at least 80% of the sulfur oxide from the waste gas, and wherein said emissions control system is further configured to use less than 30% of the energy generated by the power plant.

58. The emissions control system of any of claims 55-57, wherein the emissions control system is configured to accept at least 10% of the industrial waste gas from the power plant.

59. The emissions control system of any of claims 55-58, wherein the emissions control system is configured to accept an alkaline solution from an electrochemical system configured to produce a caustic solution.

60. The emissions control system of claim 59, wherein the electrochemical system comprises an anode, a cathode, and at least one ion-selective membrane between the anode and cathode.

61. The emissions control system of claim 60, wherein the electrochemical system is configured to operate at a voltage of 2.8V or less applied across the anode and the cathode.

62. The emissions control system of any of claims 55-61, wherein the emissions control system is configured to accept a pH adjusting agent, wherein the pH adjusting agent comprises an industrial waste, a naturally occurring pH adjusting agent, a produced pH adjusting agent, or any combination thereof.

63. The emissions control system of any of claims 55-62, wherein the emissions control system is configured to operate at a liquid flow rate to gas flow rate ratio (L/G) ranging from 5 to 5,000 gallons per minute/1000 actual cubic feet per minute.

64. The emissions control system of claim 63, wherein the system is configured to operate at a liquid flow rate to gas flow rate ratio (L/G) ranging from 100 to 500 gallons per minute/1000 actual cubic feet per minute.