GB2573124A - Near zero emission exhaust system - Google Patents

Abstract

A method of producing carbon carbonate from the exhaust 2 of an engine 1 a vehicle (e.g. ship, train trucks) comprises treating the exhaust gas to remove particle matter, sulphur dioxide (SO2) and carbon monoxide (CO); passing the gas through a condenser to separate demineralised water from the gas that is stored in a reservoir 40. The nitrogen/carbon dioxide rich gas is cooled 13 and passed to a catalysed carbon capture system comprising a hydration tank 21 containing water and nickel nanoparticles through which the gas is bubbled and converted to carbonic acid (CO3H2); a separator 32 to remove the nanoparticles; a settling tank 41 where sodium hydroxide (NaOH) and calcium chloride (CaCl2) is added to the acid to produce carbon carbonate at a temperature below 1400 centigrade. The carbonate may be disposed of at sea. The reclaimed water may be used to emulsify the engine’s fuel 16, used as part of a humid air motor system; or used to supply the vehicles water supply e.g. drinking water. Alternatively reactors having microbes, enzymes or electro chemical synthesis of calcium carbonate may be used to capture carbon dioxide. The exhaust gas may also be purified with a CO2 scrubbing device.

Description

METHOD OF RECAIMING AND UTILIZING WATER AND CARBON DIOXIDE FROM THE EXHAUST TO CREATE NEAR ZERO GREENHOUSE GAS EMISSION EXHAUST SYSTEM.

BACKGROUND TO INVENTION

Carbon dioxide (CO2) is released into the atmosphere by the burning of fossil fuels. The preindustrial carbon dioxide level was around 278 ppm and had stayed fairly constant for several centuries. In the 20th century atmospheric carbon dioxide levels have increased from about 315 ppm in 1958 to 378 ppm at the end of 2004. Thus, since the beginning of the industrial revolution the concentration of carbon dioxide in the atmosphere has increased by around 36%. Carbon dioxide is a greenhouse gas, contributing to the increasing of the temperature of the earth. Carbon dioxide from the atmosphere is also absorbed by the oceans where it forms carbonic acid and increases the acidity of the water, impacting on populations of many life forms and threatening delicate ecosystems such as coral reefs.

One method of reducing the amount of carbon dioxide in the atmosphere is to capture and store it as it is produced rather than release it into the atmosphere.

Of the various approaches to the capture and storage of carbon dioxide, the one that has gained the interest of governments and industries is storage of carbon dioxide in geological forms. The geological storage of carbon dioxide can be achieved in two ways: a) separate the carbon dioxide and pump it into empty or depleted oil wells (both terrestrial and oceanic oil wells can be used); or b) to convert it into calcium carbonate and dispose of it as landfill. One limitation of method a) is that there has to be a continuous monitoring of the oil well for possible leaks (especially for oceanic storage). The conversion to calcium carbonate for use in landfill is considered to provide a more reliable solution to the problem of carbon dioxide storage.

Calcium carbonate is a thermodynamically stable material and is abundantly found on the earth's surface. The calcium carbonate present on the earth is estimated to be a carbon reservoir equivalent to 150,000 x 10 metric tons of carbon dioxide about 4% of the earths crust. It is the main component of shells of marine organisms, snails, pearls, and eggshells and is a completely stable mineral, widely used in the building industry to make cement and other materials and also in hospitals to make plaster casts.

With concerns about global warming caused by C02 emissions, research into zero emission engines has become a priority. With small land-based vehicles, electric engines are the preferred route. However at sea battery power is not an option. The best way forward for the marine industry is carbon capture and utilisation. Captured C02 and water can be used as feed-stocks for a carbon to calcium carbonate reactor. This invention proposes reclaiming water from a ship's exhaust and processing the C02/nitrogen residual gas stream into calcium carbonate which can then be disposed of at sea with the environmentally beneficial effect of reversing the acidification of the ocean which is itself caused by the growth of C02 in the atmosphere so this invention will not only remove C02 from the atmosphere it will help to reverse some of the acidification of the sea caused by the man made increase of C02 in the atmosphere. A win- win situation.

At present the research into carbon capture and utilisation has concentrated on large industrial plants like power stations and cement works; but with land based system different prime considerations come to the fore. There is a patent (Hsu 2014, Zero emission power plant with C02 waste utilisation) which outlines the nature of the problem and claims a system for a zero emission plant in a land-based situation.

For example, at land-based industrial sites the best thing economically to do with the C02 that can be reclaimed from the flue gas is to store it on-site for future use in manufacturing or for transporting to long term storage, for example in underground worked-out oilfields. Water in a land-based industrial plant is normally available on-site more cheaply than via reclaiming it from the exhaust. The industrial process will be scaled up to make it as economic as possible and there will be no particular incentive to produce any specific carbon based product. They will produce the carbon-based product that is most economically advantageous for them, and that will be the one with the highest resale value. Also given the large scale of the operation a chemical process at high temperature and high energy use is likely to be used for the reactor. (e,g Fisher Trope or Sabatier reactors well known to those skilled in the art.)

Mobile systems have a different set of problems. A problem would arise with what to do with the carbon-based product that was produced. The logistics of on-board storage, land based offloading infrastructure and collecting and marketing of the carbon-based product that had been produced, given the relatively small scale of the operation, would not make it economically viable. The resulting carbon-based product, if it is to reduce C02 emissions as economically as possible, must be fed back to the ship's engine as fuel or turned into an environmentally friendly product for disposal at sea. With the current state of technology no low cost low energy method of converting the C02 in the exhaust to fuel (e.g. methanol) exists so conversion of the C02 into calcium carbonate for disposal at sea is the only current viable option.

Nitrogen oxides (Nox) act indirectly as greenhouse gasses by producing the tropospheric greenhouse gas ozone via photochemical reactions in the atmosphere. The best possible current technology for Nox reduction in VC engines is the on board production of emulsified fuel. It is another primary object of this invention to provide a source of water reclaimed from the exhaust for use in an on board fuel/water emulsification device. DNVKema had a project that found that on board carbon capture and storage was theoretically possible but that the practicalities involved in on shore handling and selling the C02 produced when the shipped docked and of building the onshore infrastructure involved stopped them pursuing the project beyond the theoretical stage. (lyttp://www.ship-technology7, com/features/featureonboard-carbon-capture-dream-or-reality/')

This invention proposes that rather then produce C02 the exhaust stream is cooled to below lOOdegrees centigrade thus separating the water from the gas stream then further cooling the nitrogen/C02 gas steam to below 50degrees centigrade before passing it to to to a calcium carbonate reactor.

This invention proposes that the C02 gas stream can be processed into calcium carbonate that can be disposed of at sea thus avoiding the need for on shore infrastructure or massive storage tanks on board ship or energy intensive conversion of C02 to fuel. The nitrogen is inert and can pass through the calcium carbonate reactor and be vented to air.

It is the object of this invention to take known technologies and put them together in a viable, low cost but unique way to function on a mobile platform. As technologies improve it is probable that the system described could be used on larger scale land based vehicles,

SUMMARY OF THE INVENTION

The object of this invention is to have an exhaust system that down stream of the pollution control devices ( Selective catalytic reduction unit, Sox scrubbers) uses cold seawater to reduce the temperature of the exhaust stream to below 100 degrees centigrade this would have the effect of dividing the exhaust stream into a stream of water and a stream of carbon dioxide / nitrogen. Nitrogen is inert so this gas stream who’s temperature must be reduced to below 50 degrees centigrade can be passed directly to a C02 to calcium carbonate reactor the product of which can safely disposed of at sea. The remaining exhaust consists of nitrogen and oxygen, which are not greenhouse gases these can be vented to atmosphere.. The invention has five parts; 1. The use of the C02/nitrogen gas stream from the exhaust. 2. The reclamation and use of water from cooled exhaust gas 3. The conversion of the reclaimed C02 and into calcium carbonate for disposal at sea. 4. The utilisation of reclaimed water for returning to the combustion chamber to enhance combustion. 5. The possible utilisation of some of the calcium carbonate produced to be processed into calcium oxide for use in a dry Sox scrubber (A possible secondary objective).

WATER RECLAMATION

It has been known for many years that water-vapour was a large part of the exhaust gas of an internal combustion engine and from time to time there have been patents for processes that attempt to reclaim this water (e.g. Bradley 2011) With the help of modern technology carbon monoxide, sulphur dioxide and particulate matter can be removed and then water produced by passing the exhaust stream through a condensing or membrane device.

Downstream of the dry SOx scrubber and selective catalytic reduction device, the exhaust stream consists of largely C02, nitrogen and water vapour.

The present invention also relates to utilising some of the water reclaimed from the exhaust to enhance combustion, using methods well known to those skilled in the art, specifically fuel-emulsification systems but also water-injection systems (Donahue 2006), humid air motors, steam-injection systems and any other systems like oxy/fuel combustion systems that supply water to the combustion chamber of an engine.

The effects of steam and water on combustion in I/C engines have been well known for many years. They are used to lower in-cylinder temperature and burn the air/fuel mixture more efficiently, thus helping to avoid detonation, and results in a power boost and/or fuel saving. They also allow for the use of poorer quality lower-octane fuel, as is common in ships, and have a cleaning (de-carbonising) effect on the engine and head. The more efficient bum also reduces NOX and CO emissions.

In the present invention, the cold water used to cool the exhaust gas stream can be provided by sea water. Because this water will be heated by contact with the hot exhaust stream, the heated water could become available as a energy source to power the C02 to calcium carbonate reaction. A ship is currently best suited to spare the space required for this exhaust cooling technology but large land based vehicles ( e.g.Trains) could alsouse itas the technology improves.

An alternative to a seawater based condenser is a membrane based condenser. A membrane condenser as a novel heat exchanger can overcome the weaknesses of conventional technologies in residual heat and water recovery. Actually, water vapour transport across membranes has a wide and important utilization in many industrial processes, such as desalinization of sea water, drying of natural gas, and flue gas dehydration. Membrane technology is an attractive, energy efficient alternative for molecular separations because of its high efficiency, reliability, and compact volume. It allows the selective removal of water vapour from mixture and can produce water with high purities. In addition, the membrane heat exchanger may have higher heat recovery efficiency than the conventional one because simultaneous mass and heat transfer occurs in the membrane heat exchanger.

With this invention particularly with a membrane condenser the ships water supply could be reclaimed from the exhaust.

The water reclaimed can be passed to a device for mixing with fuel by an emulsification process before passing the emulsified fuel to the combustion chamber. Fuel emulsification systems on board ships are well known to those skilled in the art (e.g. Nonox Ltd. Cottel.E 2011 or Donahue et al 2006 or Ex omission) but these are cited as non- limiting examples of adding water to the combustion process

It is a principal object of the current invention to provide a source of water for these systems by reclaiming water from the exhaust downstream of the dry SOx scrubber and selective catalytic reduction unit.

CARBON DIOXIDE RECLAMATION

According to basic chemistry principles it is possible to neutralize increased ocean acidity by adding a base, limestone. To do so it has been proposed ( Danny Harvey. University of Toronto 2008) dumping huge quantities of powdered limestone — around 4b tons every year — into the oceans A self-regulating carbonate buffering system normally helps keep the ocean's pH constant at around 8.1 — by maintaining an equilibrium between the four forms of dissolved carbon dioxide: the gas itself, carbonate ions, bicarbonate ions and carbonic acid. This delicate balance allows the oceans to absorb large amounts of carbon dioxide without much variation in seawater chemistry.

However, the rapid build-up in carbon dioxide levels over the last few decades now threatens to overwhelm the system, with some scientists projecting that pH levels could drop 0.5 units by 2100 — wiping out most of the world's coral reefs and adversely affecting the majority of marine organisms.

Adding limestone (or calcium carbonate) would have the dual effect of mitigating the process of ocean acidification and increasing carbon sequestration, though the latter would predominate. The reason is that the limestone, by bolstering the carbonate buffering system, allows the surface waters to take up more carbon dioxide. As more is drawn down, however, the neutralizing effect of the calcium carbonate begins to diminish — resulting in an overall slight decrease in acidity.

This process would take a long time, it could take several decades (and many hundreds of billions of tons of limestone) before the limestone accomplishes its objective — and that's assuming everything goes according to predictions. Adding the limestone to regions of active upwelling could eventually lead to the sequestration of an additional 0.3b tons of carbon a year. A primary objective of this invention is the utilisation of the carbon dioxide separated from the exhaust of a marine diesel engine to use as feedstock for a C02 to calcium carbonate reactor.

The DNV project envisaged taking an existing onshore carbon capture unit design and adapting it for maritime use this involved a C02 absorber and amine regenerator.

Alternatively approaches being investigated for the capture and separation of carbon dioxide from flue gas streams include solvent, membrane, chemical looping, oxy combustion and biological fixation based approaches.

However with this system C02 separation and storage is not necessary by condensing the water the C02 /Nitrogen gas stream can be passed directly to the reactor without the need for a storage stage.

In the preferred embodiment downstream of the dry SOx scrubber and the selective catalytic reduction device (SCR) the exhaust gas stream is cooled using seawater to below 100 degrees centigrade. This cases a phase shift (gas to liquid) of the H20 in the gas stream and the condensed water can be past to a reservoir for utilisation. The C02/Nitrogen gas stream can then be cooled to below 50 degrees centigrade and passed to a C02 carbon reactor.

CARBON DIOXIDE TO CARBON BASED PRODUCT REACTORS

Given the current state of the technology, it is thought that the production of Calcium Carbonate from C02 in the exhaust should initially be used in large-scale marine engines, as they would not be subject to the physical constraints that small-scale mobile applications would present. Technology of the type is in an advanced stage of development for use with large scale industrial plants but the existence of an on-board water /C02 separation at low energy costs makes it practical for marine applications. This technology would offer the possibility of a near zero-greenhouse-gas exhaust

Land based reactors use sustainable sources like wind or solar to power them in order not to become an energy sink. At sea you cannot depend on wind or solar so the lowest temperature sustainable sources to power the reaction should be used if appropriate

The inventive step of this system is that its feed-stocks of C02 and water come from the exhaust.

The preferred embodiment for a Calcium carbonate reactor is US20150151248 A1 (Sillar)

This invention relates to the use of solid metal materials for catalysing the hydration of carbon dioxide. It also relates to methods of and apparatus for hydrating carbon dioxide and capturing carbon. The solid metal materials may be nickel nanoparticles.

This invention uses a solid metal as a catalyst for the hydration of carbon dioxide, where the solid metal is selected from Co, Ni, Cu and Zn.

It is a method of capturing carbon dioxide that comprises: reacting carbon dioxide with water in the presence of a solid metal catalyst selected from Co, Ni, Cu and Zn; adding a base and a M2+ solution to the product of the reaction between carbon dioxide and water, wherein M is selected from Ca and Mg, or a mixture of the two.

It provides for an apparatus for carbon capture; the apparatus comprising: a hydration tank containing a liquid comprising water and a solid metal selected from Co, Ni, Cu and Zn in contact with the liquid; a means for bubbling CO2 through the liquid. The nitrogen in the residual gas stream and will be vented to air after passing through the bubbler.

TECHNOLOGIES DEFINED

On board Emulsified Fuel

The most common type of type of water in in oil emulsion fuel used today is produced at the oil terminal using chemical emulsification/stabilization and delivered to the user as a fuel usually at cost greater than oil alone. Although effective for Nox reduction and removing other pollutants altering the surface tension of the fuel in order to chemically stabilize the mix inhibits the micro-explosion phenomenon and does not produce as much energy or give any of the fuel saving benefits of the un-stabilized emulsion fuel produced by on board emulsification units. Therefore use of water reclaimed from the exhaust is an essential part of this inventions claims to be a “ near zero green house gas exhaust system.” Nox gasses are an indirect greenhouse gas and emulsified fuel is the most efficient method of reducing them.

Sox Scrubbers

Particulate matter and sulphur dioxide are removed from the gas stream by scrubbers which, until recently, used water to wash the gas stream and in the process the gas stream is cooled. The wash water was then conditioned before discharge overboard. However, as the exhaust stream is cooled by the wash water it needs to be reheated before it can be passed through a selective catalytic reduction unit (SCR). More recently, dry scrubbing has been introduced: this requires an operating temperature of between 240 and 450 degrees centigrade and uses calcium oxide granules to react with sulphur dioxide to form gypsum. Gypsum is a product that has commercial value (eg. fertiliser. Gypsum from industrial exhaust systems has been cleared for agricultural use). Calcium oxide is formed by heating calcium carbonate so with this invention the calcium carbonate produced on board can be used.

Humid Air Motors (HAM) A Humid Air Motor (HAM) system is a recent technology that uses combustion air almost entirely saturated with water-vapour (humid air) in a marine diesel engine. The charge air is humidified by water-vapour produced in a humidification vessel by evaporating water directly into the charge air, using the heat from the engine or its exhaust gases. It was developed because emulsified fuel and direct water injection use large quantities of fresh water, which until now has been a precious resource on board vessels. This system employs sea-water as the cooling and humidification medium. Given the current invention and its provision of fresh water, HAM is likely to be rendered obsolete, as it is unlikely to prove as cost effective as fuel emulsification. However if future developments prove it to be efficient/cheap enough in its own right, it could use water from the exhaust in the humidification process.

The various stages of this exhaust system are either: A available proprietary items ( selective catalytic reduction units, particulate traps, fuel/water emulsification devices) A or are in an advanced state of development and covered by other people's patents (C02 to calcium carbonate reactors)

As described above, the embodiments in this application utilise chemical principles for energy conversion and power generation. All embodiments eliminate the C02 emissions from the engine exhaust and produce calcium carbonate from this C02 and water reclaimed from the exhaust. All embodiments also use this reclaimed water to enhance combustion.

Since certain changes may be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense.

DESCRIPTION OF THE PREFERRED AND OTHER EMBODIMENTS

The term ship is used as a generic term for all mobile platforms (eg. Ships, trains, trucks) that use internal combustion engines.

Figure 1 refers to the preferred embodiment 1 Engine 2 Exhaust manifold 3 Dry SOx scrubber 4 Connecting pipe between Sox Scrubber and Selective catalytic reduction unit (SCR) 5 Selective catalytic reduction unit (SCR) 6 Connecting pipe between SCR and Compressor 7 Compressor 8 Pipe between Compressor and Condensing devise using sea water as coolant 9 Condensing devise using sea water as coolant 10 Water cooling of exhaust stream device using seawater (eg water jacket) 11 Sea water feed. In/out 12 C02/Hydrogen feed pipe to condensing device to lower temperature to below 50 degrees 13 Condensing device to lower temperature to below 50 degrees 14 C02/Hydrogen feed pipe to Hydration Tank 15 Water feed from condenser to reservoir (40) and to water/fuel emulsification device (16) 16 Water/fuel emulsification device 17 Emulsified fuel feed to engine 18 Fuel supply from fuel tank to emulsification device. 19 Fuel tank 20 Diesel fuel feed pipe to fuel tank 21 Ships clean water tank 22 Water feed from reservoir to NiNP mixer 23 NiNP Mixing chamber 24 C02 free gas/ nitrogen exhaust to atmosphere 25 Mixing motor and stirrer 26 NiNP , H20 feed pipe to hydration tank 27 Bubbler or sparger 28 Hydration Tank 29 Caustic Soda input pipe 30 Calcium Chloride input pipe 31 C03H2 solution plus NiNP feed to magnetic separator 32 Magnetic separator 33 C03H2 solution feed pipe to mechanical stirrer 34 Settling tank 35 Mechanical Stirrer and motor 36 Excess salt water outlets to sea 37 Screw conveyor 38 Screw conveyor motor 39 NiNP return to pipe to mixing chamber C02 Reclamation

In this embodiment of the invention, downstream of the dry SOx scrubber (3) and selective catalytic reduction unit (SRC) (4) the exhaust gas stream passes through a compressor (7) which forces the gas stream through a condenser (9). This device is cooled using sea water for example ,awaterjacket(10)By reducing the temperature below 100 degrees centigrade the gas stream is divided into it water and gas streams. The water can then be passed via pipe (15) back to the combustion chamber using methods like on board fuel emulsification or steam injection well known to those skilled in the art. The resulting hot C02/ nitrogen mix can then be passed via pipe (12) to a C02 cooling device(13) to cool the gas stream to below 50 degrees centigrade (eg. cold water injection device) then the cooled gas is passed via pipe (14) to the Hydration tank (28)

The C02 and nitrogen can then be passed to a Carbon capture by metal catalysed hydration of carbon dioxide device as outlined in UK patent GB2502085A 2013

The apparatus comprises a hydration tank 28 and a settling tank 34The hydration tank comprises a bubbler 27 (which may also be known as a sparger) which allows the gas containing CO2 to be bubbled through the hydration tank 28. The hydration tank also comprises a vent 24 situated towards the top of the hydration tank, through which any CO2 free gas can escape. In use the hydration tank will contain water and nickel nanoparticles and the CO2 gas which is bubbled through the tank will be converted to carbonic acid in solution.

The apparatus also comprises a mixer chamber 23 in which the nickel nanoparticles are suspended in water. The mixer chamber 23 comprises a mechanical stirrer and motor 25, to drive the stirrer .

The carbonic acid solution, with the nickel nanoparticles in suspension is connected to a magnetic separator 32. This separates the ferromagnetic nickel nanoparticles from the carbonic acid solution. The nickel nanoparticles are then transferred back to into the mixer chamber 23 via pipe 39 and reused in the hydration reaction. The carbonic acid solution is transferred to the settling tank 34. A NaOH solution and a CaCU solution are added to the settling tank 34 via pipes 29 and 30 solid calcium carbonate is formed, along with NaCl is solution.

The settling tank 34 comprises a mechanical stirrer driven by a motor 35.

The settling tank 34 comprises one or more outlet pipes 36 through which excess liquid, which largely comprises an NaCl solution, flows. The settling tank is connected, towards the bottom, to a screw conveyor 37 which continuously removes the solid CaCC>3 from the settling tank. The screw conveyor is driven by a motor 38.

Figure 2 refers to an embodiment of the device using oxy-fuel combustion

An oxy-fuel combustion system uses oxygen-rich air in place of ambient air in the combustion process. This is achieved by replacing the nitrogen with reclaimed water and carbon dioxide in the combustion process. In this embodiment, ambient compressed air downstream of the air filter (1) is passed through a nitrogen separation membrane (3) using a compressor (2) before being passed via an oxygen pipe (4) to the inlet manifold (6). The separated nitrogen is then vented to air.(5) The exhaust gas downstream of the engine is passed through a dry SOx scrubber (9) and selective catalytic reduction unit (SRC) (11), and from there through an exhaust stream condensing device (13). Which separates the water from the gas stream.

Water reclaimed from the exhaust is passed to a reservoir (43) and from there a portion of the water is passed via a water pipe (19) to the water/fuel emulsification device (20), where it is mixed with fuel from the fuel tank (22) before being passed to the inlet manifold (6), where it is mixed with the oxygen-rich air before passing to the combustion chamber. In the combustion chamber the C02 and water are used to replace the nitrogen in the fuel-air mix, serving to cool the combustion temperature. The C02 reclaiming and conversion to calcium carbonate is the same in this embodiment as in Figure 1. 1 Air intake 2 Compressor 3 Separation membrane 4 Oxygen supply pipe 5 Nitrogen exhaust to atmosphere 6 Inlet manifold and injectors 7 Engine block 8 Exhaust manifold 9 Dry SOx scrubber 10 Exhaust pipe between Dry SOx scrubber and Selective catalytic reduction unit (SCR) 11 Selective catalytic reduction unit (SCR) 12 Exhaust pipe between Selective catalytic reduction unit (SCR) and Condensing devise using sea water as coolant (13) 13 Water cooling of exhaust device 14 Seawater jacket 15 Sea water pipe feed and supply pipes 16 C02/Hydrogen feed pipe to condensing device to lower temperature to below 50 degrees 17 Condensing device to lower temperature to below 50 degrees 18 C02/Hydrogen feed pipe to Hydration Tank 19 Water feed from condenser to reservoir (43) and to water/fuel emulsification device (20) 20 Water/fuel emulsification device 21 Emulsified fuel feed to engine 22 Fuel tank 23 Fuel feed pipe to water/fuel emulsification device. 24 Ships clean water tank 25 Water feed to from reservoir (24) to mixing tank for H20 and NiNP (26)

26 Mixing tank for H20 and NiNP 27 C02 free gas to atmosphere pipe 28 Mixing motor and stirrer 29 NiNP, H20 feed pipe to hydration tank 30 Bubbler or sparger 31 Hydration tank 32 Caustic Soda input pipe 33 Calcium Chloride input pipe 34 C03H2 & NiNP feed to Magnetic separator 35 Magnetic separator 36 C03H2 solution feed pipe to mechanical stirrer 37 Settling tank 38 Mechanical Stirrer and motor 39 Excess salt water outlets to sea 40 Screw conveyor 41 Screw conveyor motor 42 NiNP return to pipe to mixing chamber 43 Water reservoir

The term ship is used as a generic term for all mobile platforms (eg. Ships, trains, trucks) that use internal combustion engines.

References cited :-

Hsu US0165569A1/2014

Cotell E US 7934474B2/2011

Bradley US 0168128A1/2011

Donahue et al. US 0225672A1 /2006

Sillar US20150151248 Al

Claims (1)

1. CLAIMS 1 A method for producing calcium carbonate from combustion exhaust gases, the method comprising: a) removing particulate matter and sulphur dioxide from the exhaust gases b) Treating the exhaust gas to remove carbon monoxide. c.) Condensing the filtered gas stream; the condensing cooling the filtered gas to a pre agreed temperature below 100 degrees centigrade d) Removing any water produced by the condensing process to a storage reservoir. e) Cooling the nitrogen/carbon dioxide rich exhaust gas stream to a pre-agreed temperature below 50 degrees centigrade. f) Passing the remaining exhaust gas through the bubbler of a Carbon capture by metal catalysed hydration of carbon dioxide device g) Adding controlled amounts of Caustic soda and Calcium chloride to the Carbon capture by metal catalysed hydration of carbon dioxide device and reacting the carbon dioxide together with the Caustic soda and Calcium chloride at a temperature below 140 degrees centigrade to produce pure calcium carbonate. 2 Alternatively to claim 1. A method of producing calcium carbonate from combustion exhaust gas of an internal combustion engine the method comprising a) Treating the exhaust gas to remove particulate matter and sulphur dioxide b) Treating the exhaust gas to remove carbon monoxide. c) Passing the exhaust gas through a C02 scrubbing device that will separate the gas stream into a C02 rich stream and a nitrogen/water vapour rich stream. These scrubbing methods may include utilising adsorbents that attract C02 to their surface, using selective permeable membranes that prevent C02 from passing,using selective permeable membranes that allow only C02 to pass, cooling the C02 to a temperature that forces the C02 to condense out of the solution for separation but no other C02 scrubbing technology is excluded. 3 A system according to claim lor 2 where at least some of the calcium carbonate produced is dumped at sea. 4 A system according to claim 1 where the condensing device in c) and e) uses sea water for cooling the gas stream. 5 A system in accordance with claim lor 2 where at least some of the water reclaimed from the exhaust is passed to the combustion chamber using on board fuel emulsification a system well known to those skilled in the art. 6 A system in accordance with claim lor 2 where at least some of the water reclaimed from the exhaust is passed to the combustion chamber, in order to enhance combustion by methods well-known to those skilled in the art, which may include direct water injection, steam injection, humid air motors, and replacing nitrogen with H20 and C02 in oxygen-enhanced combustion. 7 A system according to claim lor 2 where at least some of the water reclaimed from the exhaust is further purified and used for the ships drinking water supply. 8 A system according to claim 1 that passes at least some of the water from the reservoir of water that has been reclaimed from the exhaust into a humidification vessel where the water is evaporated directly into the charge air, using heat from the engine or the exhaust gases ( Humid Air Motor ). 9 A system according to claim 1 or2 where some of the calcium carbonate produced is heated to produce calcium oxide for use in a dry scrubber. 10 A system according to claims 1 Where the carbon dioxide rich gas stream and at least some of the potable/demineralised reclaimed water is passed to a reactor based in the principle direct biological conversion by microbes 11 A system according to claims 1 Where the carbon dioxide rich gas stream and at least some of the potable/demineralised reclaimed water is passed to a reactor based in the principle enzymes in bioreactors 12 A system according to claims 1 Where the carbon dioxide rich gas stream and at least some of the potable/demineralised reclaimed water is passed to a reactor electro chemical synthesis of calcium carbonate