Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
  • B01D61/58—Multistep processes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2311/00—Details relating to membrane separation process operations and control
  • B01D2311/26—Further operations combined with membrane separation processes
  • B01D2311/2623—Ion-Exchange
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2311/00—Details relating to membrane separation process operations and control
  • B01D2311/26—Further operations combined with membrane separation processes
  • B01D2311/2642—Aggregation, sedimentation, flocculation, precipitation or coagulation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2311/00—Details relating to membrane separation process operations and control
  • B01D2311/26—Further operations combined with membrane separation processes
  • B01D2311/2673—Evaporation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2311/00—Details relating to membrane separation process operations and control
  • B01D2311/26—Further operations combined with membrane separation processes
  • B01D2311/268—Water softening
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
  • B01D61/02—Reverse osmosis; Hyperfiltration ; Nanofiltration
  • B01D61/025—Reverse osmosis; Hyperfiltration
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
  • B01D61/02—Reverse osmosis; Hyperfiltration ; Nanofiltration
  • B01D61/027—Nanofiltration
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
  • B01D61/14—Ultrafiltration; Microfiltration
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F1/00—Treatment of water, waste water, or sewage
  • C02F1/42—Treatment of water, waste water, or sewage by ion-exchange
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F1/00—Treatment of water, waste water, or sewage
  • C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F2201/00—Apparatus for treatment of water, waste water or sewage
  • C02F2201/008—Mobile apparatus and plants, e.g. mounted on a vehicle

Definitions

• This disclosure relates generally to the manipulation of ion concentration to dynamically manage performance of ion exchange systems and processes
• the system may be highly adaptable to differing remediation requirements, scalable to maximize efficiency, and modular to perform all remediation needs including outputting water within safety standards as well as processing the removed contaminants to final disposition standards.
• noun, term, or phrase is intended to be further characterized, specified, or narrowed in some way, then such noun, term, or phrase will expressly include additional adjectives, descriptive terms, or other modifiers in accordance with the normal precepts of English grammar. Absent the use of suc adjectives, descriptive terms, or modifiers, it is the intent that such nouns, terms, or phrases be given their plain, and ordinary English meaning to those skilled in the applicable arts as set forth above.
• Figure 1 depicts a typical breakthrough curve .
• Figure 2 is a graph depicting the relationship between the concentrations of influent ions to the capacity of the media without a concentration step.
• Figure 3A depicts the concentration of influent ions and the capacity of the media with and without a concentration step when all ions in the liquid are concentrated equally.
• Figure 3B is a graph showing a comparison between the concentrations of influent ions to the capacity of the media with and without a concentration step wherein the concentration step results in higher concentration of one ion with respect to the other ions in the liquid.
• Figure 3C is the graph of Figure 3B wherein the concentration step also increases the capacity of the media.
• Figure 4 depicts the mo vement of the curve to achie ve maximum capacity as the concentration step increases the ion to the ion exchange (IX) media.
• Figure 5 depicts an exemplary nanofilter.
• FIG 6 is an isometric view of an example embodiment Mobile Processing System (MPS) comprising five separate skids.
• MPS Mobile Processing System
• Figure 7 is a top view of the example embodiment of Figure 6.
• Figure 8 depicts an example configuration of MPS skids.
• Figure 9 depicts the MPS configuration of Figure 8 with the addition of a Nanofiltration skid.
• Figure 10 depicts the MPS configuration of Figure 9 with the addition of an ISM skid for processing of the permeate stream ,
• Figure 11 depicts two possible storage configurations comprising of a Permeate Collection Tank and a Concentrate Collection Tank.
• Figure 12A depicts an embodiment of a nanofiltration step.
• Figure 12B depicts the embodiment of Figure 12A with example flow rates and tank volumes.
• Figure 13 depicts an embodiment that includes a precipitation process.
• Figure 14 depicts an embodiment that includes a metal hydroxide precipitation process.
• Ion exchange (IX) materials operate on the conditions of equilibrium between ions in solution and ions in the media, such that if a particular ion in the solution is not in the media, there is a dynamic where a percentage of the ion will enter into the material creating equilibrium.
• Ion exchange materials have varying capacities for ions, meaning that there is limited space for a given ion in the material. This varying capacity in operation can be termed the "effective capacity" and should approach the theoretical capacity of the material.
• All IX media contain counter ions, such as (FT) or (OH " ) that are exchanged when the material comes in contact with other ions (such as Na ⁇ , Ca "1' , CT, etc.).
• the extent of the exchange is a function of the material itself, the physical conditions of the solution, and the concentration of ions in the solution.
• the equilibrium between an IX media and any given ion, X is dependent on the concentration of that ion (X) in solution and other ions that may compete with it for IX sites.
• concentration technologies such as nanofiltration, reverse osmosis, and evaporation the total concentration of the ion will increase. This increases the driving force forXto be sorbed by the IX material allowing the "effective capacity" of the media to more closely approach the theoretical capacity.
• the addition of a concentration step prior to ion exchange increases the rate of reaction in the ion exchange media thus increasing the operating efficiency of the media by reducing processing time.
• chemicals can be added such that the nanofllter selectively concentrates one ion (or group of ions) over another ion (or group of ions). For example, it can increase the strontium, concentration by four times in the concentrate stream while the sodium concentration remains the same, in some embodiments.
• the ratio of ion X to ion Y may be increased, such that the driving force to reach equilibrium is increased by reducing the relative competition from Y.
• concentration can be controlled using other methods, but in general, the concentrations of all ions may be increased at the same factor. This results not in a better ratio of to Y, but an overall ionic driving force in the equilibrium system by mass action. Evaporation methods work in a similar manner as reverse osmosis systems.
• This concept can be applied in any treatment of solutions containing ions, and in which a sorption materia] (IX, adsorption, or absorption material) is used.
• a sorption materia] IX, adsorption, or absorption material
• the adsorption or absorption materials may work in a similar manner, however in a different mechanism.
• This concept is primarily used to optimize loading of a target ion, or species, on a material and to reduce overall waste generation. In some embodiments the performance of the media is determined by the amount of waste produced wherein a smaller amount of waste is indicative of better performance.
• Figure 1 depicts a typical breakthrough curve that is plotted as final concentration (C) (effluent) divided by initial concentration (Co) (influent) with respect to time (t), as depicted, or volume (v). This represents a normalization of the ions with respect to concentration.
• the steepness of the breakthrough curve determines the extent to which the capacity of a sorbent bed can be utilized. Thus, the shape of the curve is instrumental in determining the length of the sorption bed.
• a steeper curve indicates a quicker reaction which is indicative of improved operating efficiency. Improving operating efficiency allows for a larger volume to be processed in a shorter amount of time.
• Figure 2 depicts the relationship between the ion concentration and the capacity of the media. The performance of ion exchange media in a column or batch mode is dependent on the total ion
• An ion exchange media also has a maximum theoretical capacity (defined in m eq /g or m eq /L), which can only be met under certain conditions. In normal operating conditions, this capacity is rarely met due to
• the concentrate stream is the portion of the liquid containing a greater concentration of ions after processing.
• the concentrate stream is the portion of the liquid that does not pass through the membrane.
• the concentrate stream is the portion of the liquid that is not evaporated.
• the penneate stream is the portion of the liquid containing a smaller concentration of ions after processing.
• the permeate stream is the portion of the liquid that passes through the membrane.
• the permeate stream is the portion of the liquid that is evaporated.
• FIGS. 3A through 3C graphically depict the capacity of the media in relation to the ion concentration and the difference between the use of a concentration step and without a concentration step.
• Figure 3A is a graph showing the concentration of influent ions to the capacity of the media with and without a concentration step when all ions in the liquid are concentrated equally.
• Figure 3B is a graph showing a com parison between the concentrations of influent ions to the capacity of the media with and without a concentration step wherein the concentration step results in higher
• FIG. 3C is the graph of Figure 3B wherein the concentration step also increases the capacity of the media.
• a first set of ions X is concentrated by a factor of A
• a second set of ions F is concentrated by a different set of factors B (wherein B is less than A) the effective capacity of the media to retain Xis increased.
• Figure 4 show s the upw ard movement of the curve to achiev e maximum capacity of the media and a concentration step increases the ion to ion exchange (IX) media.
• a nanofilter conditioning step is used to increase the concentration of one or more select target species (e.g. magnesium, calcium, and strontium, among others) and improve the utilization of the ion exchange media.
• Figure 5 shows an isometric view of an exemplary nanofilter. Nanofiltration is a separation process that utilizes diffusion through a membrane with a typical pore size between 0.1 to 10 nanometers. Unlike reverse osmosis membranes, nanofilter membranes operate at lower pressure and offer selective solute rejection based on size. The pressure differential between the two sides of the membrane facilitates the nanofiltration process.
• Application of a nanofilter creates a concentrate stream with greater concentration of target species (e.g., magnesium, calcium, and strontium) while allowing monovalent species to pass to the permeate stream.
• target species e.g., magnesium, calcium, and strontium
• the media loading capacity increases as the concentration of the select target species increases. Preliminary testing of the concentrate stream composition did not show significant difference in loading capacity from the reduced ratio of multivalent to monovalent ions.
• Table 1 shows preliminary analyses that illustrate an example embodiment wherein the ion exchange media loading capacity is a function of magnesium concentration. As magnesium concentration increases, so does the loading capacity. A similar effect can be achieved for other target species such as calcium and strontium, among others.
• the nanofilter is a 5:3:2 tube array.
• the nanofilter elements are eight inches in diameter and forty inches in length. In some embodiments there are six elements per tube. In some embodiments, the tubes may be twenty-one feet long.
• the Nanofilter skid comprises a three stage array and associated equipment and may be contained within a single enclosure. Other configurations are possible and considered.
• more than one nanofilter, or array of nanofilters may be used where each nanofilter, or array of nanofilters, is implemented to concentrate a specific target species in the liquid.
• one or more nanofilters or nanofilter arrays may be mounted in one or more mobile skids.
• one or more Nanofilter skids may be used wherein each skid may contain one or more nanofilters and wherein each skid is operable to concentrate a specific target species in the liquid.
• one Nanofilter skid may be used wherein the Nanofilter skid comprises one or more nanofilters each operable to concentrate a different target species in the liquid.
• Solids Removal skids 220 comprising one or more solids removal filters (SRF) may be used to reduce, or remove, the suspended solids in the process liquid.
• SRF solids removal filters
• a reverse osmosis conditioning step is used to increase the concentration of one or more select target species (e.g. magnesium, calcium, and strontium, among others) and improve the utilization of the ion exchange media.
• Reverse osmosis is capable of separating granular particulate such as sand, sediment, or other suspended solids, as well as molecular compounds and ions provided their physical size is larger than that of the solvent.
• Application of reverse osmosis creates a concentrate stream with greater concentration of ions (e.g., magnesium, calcium, and strontium) while allowing water to pass to the permeate stream.
• the media loading capacity increases as the concentration of the ions in the process liquid increases.
• Osmosis is the spontaneous tendency for water to move concentrations across a pressure gradient of high to low. For example, if one gallon of saline water is connected to one gallon of distilled water and allowed to sit, after a period of time both gallons would contain an equal concentration of saline. The dissolved molecules will balance out across the concentration gradient of high to low, resulting in two equal midpoint concentrations.
• Reverse osmosis is a forcibly applied inverse of natural osmosis in which a single volume of concentrated liquid is separated into solute and solvent. The process is typically employed for the desalinization and filtering of drinking water, but can be applied to most any liquid processing operation.
• the process may be accomplished by employing an outside force such as a pump, gravity, moving plate, or any other means of applying a force, to the solvent, and forcing it through a semi -permeable membrane.
• the semi -permeable membrane contains holes or gaps large enough for the solvent to pass through while leaving the solute behind.
• a high saline concentration solvent is forced through a semi -permeable membrane comprised of holes large enough for I Q molecules, but small enough to prevent Na + or (X ions from passing through. These ions are both larger than an H 2 0 molecule, so any amount can be filtered out of the solvent regardless of ion concentration or mass of solute present.
• Evaporation/crystallization is a treatment option that removes liquid from dissolved solids (as opposed to other options where the dissolved solids are removed from liquid).
• the overall ion concentration increases because the amount of ions in the liquid remains the same while the volume of the liquid decreases.
• evaporation/crystallization systems are implemented to completely remove the liquid from the solids in solution; however, for the systems and methods disclosed herein it is beneficial to use evaporation/crystallization systems to reduce the volume of the liquid resulting in a solution having a greater concentration of ions.
• increasing the concentration of ions in solution increases the performance of ion exchange media.
• An embodiment utilizes an evaporation/crystallization system to reduce volume of source liquid thus increasing ion concentration in the liquid. This approach does not add chemicals to precipitate solids.
• the first step in the process may be pH adjustment and de-gassing of the liquid stream to remove bicarbonate alkalinity. This operating step may be done in three stages (acidification, de-aeration, re-alkalinization), in some embodiments, and results in a liquid stream that protects the downstream evaporator/crystallizer components from scaling.
• the recirculating concentrated slurry may be taken off as a slip stream to a dewatering system to produce a 90wt% suspended solids stream, in some embodiments.
• the liquid recovered from dewatering the solids may be recycled through the evaporator/crystallizer and/ or one or more additional evaporators and/or crystaliizers, in some embodiments.
• processing equipment may be modular.
• the processing equipment may be contained within a modular enclosure, or skid, much like the MPS skids.
• water treatment flow capacity is 400 m'/ ' day (16.7 nr'/ ' hr).
• Other flow rate capacities and processing equipment are considered.
• Processing equipment for any flow rate capacity may be modular in design.
• power consumption for the facility, with equipment is estimated to be about 1 100 kW. The power consumption is predominantly for the evaporation process and thus a function of the flow rate and not the dissolved solids content.
• the equipment may include one or more auxiliary boiler to produce steam for startup purposes to operate the crystallizer heater until the vapor generation is sufficient to drive the crystallizer heater.
• the processing options discussed above, and others not expressly described herein, may be mobile or modular in design.
• the systems and methods disclosed herein may be included in mobile modules such as those disclosed in co-pending application entitled Mobile Processing System (MPS) for Hazardous and Radioactive isotope Removal, Ser. No. 14/748,535 filed June 24, 2015, with a priority date of June 24, 2 14, which is herein incorporated by reference in its entirety .
• MPS Mobile Processing System
• the Mobile Processing System is designed to be both transported and operated from standard sized intermodai containers or custom designed enclosures, referred to herein as skids or modules, for increased mobility between sites and on-site, further increasing the speed and ease with which the system may be deployed.
• the system may be completely modular wherein different modules perform different operations in a modular liquid remediation process.
• the skids may be connected in parallel and/or in series in order to perform all of the process requirements for any given site.
• a further advantage of the MPS is the availability of additional modules for further processing of the contaminants removed from contaminated liquids such that the contaminants do not need to be transported from the site for further processing prior to final disposition,
• the MPS may comprise one or more forms of liquid processing. Depending on the needs of the particular site, one or more different processes may be used. In some embodiments, one or more of the same modules may be used in the same operation. For instance, two or more separate ion specific media (ISM) modules may be used in series and/or in parallel. In some embodiments one or more ISM modules in a series may each be operable to remove a specific ion from the waste stream. Another example is placing two or more of the same module in parallel to handle an increased flow capacity or to bring one or more modules online while one or more others are brought offline for maintenance. For processes that take more time, such as feed/blend in some embodiments, it may be advantageous to place one or more modules in parallel to reduce overall processing time. Other configuration variations not expressly- disclosed herein may be implemented.
• FIG. 6 is an isometric view of an embodiment of a MPS comprising five separate skids: a Control and Solids Feed skid 140, a Feed/Blend skid 30, a Solids Removal Filter skid 120, an Ultra Filter skid 110, and an Ion Specific Media (ISM) skid 100.
• the five skids depicted in Figure 6 can be arranged in different operation modes that allow for flexibility in accommodating specific processing needs.
• Some embodiments may comprise one or more types of skids not depicted in Figure 6 such as one or more Nanofiltration skids 250 (FIG. 9), Reverse Osmosis skids (not shown), and
• FIG. 7 is a top view of the system of Figure 6.
• the five skids of Figure 6 are depicted side by side but do not necessarily have to be in this configuration on site.
• the skids may be positioned as required by the topography of the site,
• the equipment may be configured to use six or more ISM vessels in series, or parallel, by connection of two or more ISM modules.
• the determination of the number of ISM vessels required is dependent on the loading capacity of the media, the target species, and the size of the vessels.
• the loading capacity of the media is a function of the concentration of the target species. Preliminary testing indicates higher loading capacity for higher magnesium concentration, for instance.
• Figure 8 depicts an example configuration of four MPS skids: a Powder Feed/Controls skid 240, a Feed Blend skid 230, a Solids Removal skid 220, and an ISM skid 200.
• the Solids Removal skid 220 with the solid removal filters may be used to protect the ion exchange columns with the aim of accounting for the potential presence of suspended solids.
• the ISM skid 200 may be configured to utilize one or more ISM vessels in series and/or in parallel. Some embodiments utilize more than one ISM skid 200 in series and/or in parallel. The configuration, type, and number of skids may vary between embodiments. Processing may continue until a target residual ion concentration is attained for one or more target species.
• the selected endpoint is magnesium removal until the residual magnesium concentration is 200 ppm or less, which may then be treated by other treatment systems, if necessary to meet certain regulations, standards, and/or requirements.
• the amount of media required is based on the desired end concentrations of one or more target species.
• the process liquid may be continuously cycled through the system until it meets process or other requirements.
• the process liquid may proceed to secondary processing where it may be treated by other low conceniraiion treatment systems, if necessary to meet certain regulations, standards, and/or requirements.
• the system may incorporate a number of valves.
• the valves may be of one or more different types.
• Check valves may be used through the system to prevent flow from flowing backwards.
• Many of the valves may be motor operated to allow for quick shutoff or open as necessary to prevent leaks or reduce pressure.
• Pressure relief valves may be used to automatically release pressure when the system pressure exceeds a predetermined value.
• Motor operated valves may be designed to fail as-is, open, or closed depending on their location in the system to minimize damage and environmental hazards in the event of failure. Redundant valves may be used throughout the system to provide additional control and increase the factor of safety of the system, reducing the possibility of leakage to the environment in the event of a failure.
• Valves are disclosed in more detail in co-pending application entitled Mobile
• the concentrate stream may be processed using a Mobile Processing System (MPS).
• MPS Mobile Processing System
• Figure 9 depicts an embodiment utilizing a Nanofilter skid 250 as a form of a conditioning step that is incorporated into the MPS configuration of Figure 8.
• Some embodiments may comprise one or more Reverse Osmosis skids, Evaporation/Crystallization skids, and/or Nanofilter skids 250 for ion concentration.
• the configuration, type, and number of skids may vary between embodiments.
• the Nanofilter skid 250 is used for further embodiment descriptions as the example concentration method; however it should be noted that other concentration methods may be used.
• the Nanofilter skid 250 separates the source liquid into a permeate stream and a concentrate stream.
• the concentrate stream containing the greater concentration of multivalent species is sent to MPS, in the depicted embodiment.
• the permeate stream may be processed, stored, reused, or released to the environment depending on the types and concentrations of contaminants remaining in the liquid.
• the permeate stream may be processed by MPS.
• one or more Solids Removal skids 220 may be used at one or more points in the system to reduce the possibility of any potential solids from fouling the systems.
• the number and location(s) of Solids Removal skids 220 required for a given embodiment is dependent on the suspended solids content in the process liquid.
• the level of suspended solids may be small in some embodiments because the inlet may be filled by decanting liquid from an evaporator collection tank.
• the number of Solids Removal skids 220 may be as low as one or two when the MPS process does not include powder addition.
• FIG 10 depicts the embodiment of Figure 9 wherein both the concentrate stream and permeate stream from the Nanofilter skid 250 proceed to an ISM skid (200a and 200b, respectively).
• the concentrate stream and the permeate stream will contain differing target species and concentrations thereof.
• Each ISM skid 200a and 200b is operable to remove one or more target species present in the stream it receives for processing,
• Figure 11 depicts an embodiment that utilizes the Nanofilter skid 250 to process the source liquid into a Permeate Collection Tank 310 and Concentrate Collection Tank 320.
• the filtered liquid containing the monovalent species is sent to the Permeate Collection Tank 310 while the concentrate stream containing the multivalent species is sent to the Concentrate Collection Tank 320.
• one or both of the liquid streams exiting the Nanofilter skid 250 may be processed, stored, reused, or released to the environment depending on the types and concentrations of contaminants remaining in the liquid.
• the liquid in the Concentrate Collection Tank 320 may be higher in target species concentration (compared to the source liquid concentration), which may improve the effectiveness of the media.
• Recirculation through the MPS skids and back to the Concentrate Collection Tank 320 may allow for more complete use of the media capacity.
• the projected chemistry- for the Concentrate Collection Tank 320 in some embodiments, is not near the saturation point for one or more target species; therefore, solids are not expected from the concentration operation ,
• Figure 12A depicts an embodiment that utilizes an ISM skid 200 to capture one or more target species from the concentrate stream. Since the amount of liquid to be processed is directly proportional to the amount of ion exchange media needed in some embodiments, the use of the Nanofilter skid 250 aids in reducing the amount of the liquid to be treated by filtering out the permeate stream that is sent to the Permeate Collection Tank 310, in the depicted embodiment; hence, maximizing the use of the ion exchange media and reducing the amount of ISM vessels needed.
• the concentrate stream may pass directly from the Nanofilter skid 250 to the ISM skid 200.
• the permeate stream may pass directly from the Nanofilter skid 250 to a separate ISM skid 200.
• each skid may utilize one or more of each skid. In some embodiments more than one concentration skid may be used wherein each concentration skid is used to concentrate a different particular target species. In some embodiments the system may comprise more than one ISM skid 200 wherein each ISM skid 200 may be specific to different particular target species. In some embodiments both the concentrate stream and the permeate stream may proceed to separate ISM skids 200 wherein each ISM skid 200 is operable to remove one or more particular target species present in each stream.. [0074] In some embodiments the source liquid may have been previously processed. In some embodiments the source liquid may have been previously processed for a different target species prior to processing in the depicted systems. In some embodiments the source liquid is a concentrate stream.
• the source liquid is a permeate stream.
• Some embodiments may comprise a series of Nanofilter skid 250 and ISM skid 200 pairs wherein each pair is operable to process a particular target species.
• the processed liquid exiting the ISM skid 200 may proceed through one or more systems of Nanofilter skid 250 and ISM skid 200 pairs wherein each pair is operable to process a different target species.
• the permeate stream may be stored in a Penneate
• Collection Tank 310 proceed directly to other processing or storage systems, or be released if it meets release standards.
• Figure 12B depicts the embodiment of Figure 12A with example flow rates and tank volumes.
• a 7500 m 5 Permeate Collection Tank 310 is used for receiving the permeate stream from the Nanofilter skid 250 while a 2500 rn J Concentrate Collection Tank 320 is used for receiving the concentrate stream .
• a source liquid may be supplied to the Nanofiltration skid 250 at 220 gpm; the permeate stream may be delivered to the Permeate Collection Tank 310 at 165 gpm while the concentrate stream may be delivered to the Concentrate Collection Tank 320 at 55gpm.
• the same or similar flow rates may be applied to other configurations. Other embodiments may have different flow rates and tank volumes.
• Precipitation is different than nanofiltration, reverse osmosis, and evaporation/crystallization in that it results in a concentrate stream containing the target species and one or more precipitated solids instead of a permeate stream.
• a precipitation agent may be added to facilitate the extraction of one or more precipitants.
• Precipitation of one or more solids from solution increases the ratio of the remaining target species with respect to the precipitant species such that the driving force to reach equilibrium is increased by reducing the relative competition from the precipitant species. This increase in driving force results in more effective use of the ion exchange media thus increasing the capacity of the media.
• Figure 13 depicts a generic embodiment of a precipitation process that involves the addition of a precipitation agent for the removal of one or more precipitant.
• a Precipitation skid 375 follows a Nanofilter skid 250 prior to an ISM skid 200.
• the permeate stream is routed to a Permeate Collection Tank 310.
• the permeate stream may be processed, stored, reused, or released to the environment depending on the types and
• the concentrations of one or more target species, such as magnesium, calcium, and strontium, in the concentrate stream can be significantly reduced with the use hydroxide precipitation.
• the difference in solubility and precipitation pH can be used to selectively extract and reduce the amount of one or more target species.
• Figure 14 depicts the precipitation process embodiment of Figure 13 where the precipitation agent is a hydroxide.
• hydroxide ions are introduced to the concentrate stream containing the metals to be extracted aiding in the precipitation of a target species such as magnesium, calcium, and/or strontium.
• Metals precipitate at various pH levels depending on the form of the metal, chemistry of the source liquid, and presence of other metals and chelates.
• the pH level can be adjusted to target specific species.
• the pH may need to be carefully controlled because some metals are amphoteric in nature and the presence of chelating agents can also interfere with the ability for metals to precipitate.
• magnesium hydroxide is the targeted prec itant though strontium hydroxide and calcium hydroxide may also form .
• Magnesium hydroxide is the more insoluble than strontium hydroxide and calcium hydroxide regardless of liquid temperature and has a lower precipitation pH of 9-10 so it is likely to precipitate first.
• Both strontium hydroxide and calcium hydroxide are slightly soluble in the same pH range as magnesium, but most likely will not precipitate. An increase of the pH may result in the precipitation of strontium hydroxide and calcium hydroxide, since both have a solubilit ' pH around 12.
• the difference in the solubility of strontium hydroxide and calcium hydroxide can be used to selectively extract one from the other. This means that the relationship between solubility and temperature may be used to precipitate one while the other remains the liquid.
• the solubility of strontium hydroxide is directly proportional to temperature; hence, lowering the temperature of the liquid would decrease the solubility of strontium hydroxide and increase its precipitation rate.
• the solubility of calcium hydroxide is inversely proportional to temperature; hence, increasing the temperature of the liquid would decrease the solubility of calcium hydroxide and increase its precipitation rate.
• Calcium hydroxide being more insoluble than strontium hydroxide would likely precipitate after magnesium hydroxide and before strontium hydroxide with an increase in pH of the stream to around 12, depending on temperature of the process liquid.
• An increase in temperature of the liquid may improve the efficiency of calcium hydroxide precipitation, while the strontium hydroxide becomes more soluble and remains in solution.
• the remaining strontium in solution may be concentrated in a nanofiltration step and removed in an ion exchange step.
• the concentrate stream may be cooled to facilitate the precipitation of the strontium hydroxide.
• the precipitation of strontium hydroxide occurs when the temperature of the solution is around 25°C to 30°C. If the strontium hydroxide precipitation upon cooling isn't sufficient, carbon dioxide gas can be introduced into the solution to increase the efficiency of the strontium hydroxide precipitation.
• the advantage of using sodium carbonate and/or sodium hydroxide in the removal of magnesium, calcium, and strontium is that the remaining sodium in the liquid may be crystallized with the chlorides (as shown on Table 2) to form sodium chloride salt.
• the precipitants can then be recovered with the use of conventional processes such as filtering.

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• Engineering & Computer Science (AREA)
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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Separation Using Semi-Permeable Membranes (AREA)
• Water Treatment By Sorption (AREA)
• Treatment Of Water By Ion Exchange (AREA)
• Heat Treatment Of Water, Waste Water Or Sewage (AREA)

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• 2017
  • 2017-01-24 CA CA3006319A patent/CA3006319A1/en not_active Abandoned
  • 2017-01-24 WO PCT/US2017/014750 patent/WO2017132151A1/en active Application Filing
  • 2017-01-24 EP EP17705211.5A patent/EP3408011A1/de not_active Withdrawn
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