Carbon capture system and method for cryogenic fueled device

Abstract

A carbon capture system for an LNG fueled power plant (1) and method for LNG combustion and carbon capture, wherein the method comprises - gasifying the LNG stream by heating to obtain a gasified NG stream - combusting the gasified NG stream to obtain exhaust gas stream- separating water from the cooled exhaust gas stream to obtain a dry exhaust gas stream - adsorbing CO2 from the dry exhaust gas stream to obtain a CO2 depleted exhaust gas stream - desorbing CO2, pressurizing it and cooling it with the cold from the gasification of the LNG - separating CO2 from the desorbing stream.

Description

[0001] Carbon capture system and method for cryogenic fueled device

[0002] The present disclosure relates to a carbon capture system, more particularly to a hybrid carbon capture system for cryogenic fueled device combining the handling of the cryogenic fuel with a post combustion carbon capture system. The present disclosure also relates to a method for LNG combustion and carbon capture.

[0003] Background

[0004] Current systems for carbon capture being used and developed by the industry employs solutions for carbon capture that require significant parasitic energy. Carbon capture systems including amine carbon capture, cryogenic carbon capture or membrane carbon capture are resulting in a significant parasitic energy loss which reduces or even avoid economic feasibility of carbon capture projects. The term “parasitic energy loss” is used herein to refer to the supplemental energy required to capture, compress, carbon dioxide (CO2) emissions from a source. This auxiliary energy demand is considered parasitic because it diverts energy from the primary function of the system, typically associated with but not limited to electricity generation.

[0005] A typical carbon capture system for a power system uses an amine loop system and is completely independent of the regasification unit required to vaporize an LNG that is used as a fuel. Amine system have a large footprint and, due to the amount of equipment required and the geometry of the equipment, it’s not feasible for smaller application. The use of amine system is an energy intensive process. Therefore, to implement a post combustion carbon capture with amine system requires a high capex and high opex, leading to problems with economic feasibility of the carbon capture process.

[0006] Conventional post combustion carbon capture systems have limited efficiency and it is not uncommon that 10% of the carbon still go to atmosphere and all the CO2 is not captured from the exhaust gas. This is due to the unfeasible size of equipment required to remove more CO2 in case of amines or the unfeasible number of membrane stages required in a membrane-based capture system. In most of present CO2 captured systems CO2 is often obtained in gaseous phase. It is generally not economically feasible to transport relevant amount of CO2 in gaseous phase (compressed) to a CO2 storage facility if it’s not connected through a pipeline. Most locations for CO2 storage are not connected with pipelines to the carbon capture plants. Prior art

[0007] Traditionally cryogenic carbon capture plants use an external fluid as a cold source to the cryogenic system. This external source is usually added as a cryogenic plant specifically for the carbon capture. These kinds of plants are expensive and requires a lot of energy to be operated.

[0008] EP2089138B1 discloses a system and method for absorbing CO2 then heating the absorbent to regenerate the absorbent.

[0009] CN109821341 discloses a method for LNG combustion and carbon capture, using the cold of the LNG to cool the flue gases from a natural gas turbine to separate the CO2.

[0010] WO20 13 / 062922 discloses systems and methods for integrated energy storage and cryogenic carbon capture. The systems and methods are focused of different functions during peak and off-peak periods.

[0011] The disclosed system requires an integrated refrigerant liquefaction plant attached to the carbon capture system. Refrigeration liquefaction plants are expensive.

[0012] WO20 13 / 062922 discloses that the liquified natural gas (LNG) used as refrigerant need to be processed from the compressed natural gas, therefore parasitic electricity is required to operate the liquefaction plant.

[0013] The disclosed system produces the refrigerant required for the carbon capture only during off peak energy times, therefore the carbon capture cannot be a continuous operation.

[0014] Objectives of the invention

[0015] An objective of the present disclosure is to provide a cost-efficient post combustion carbon capture system having liquified CO2 as a product.

[0016] Another aim is to provide for equipment that uses hybrid technology using molecular sieve technology and gasified cryogenic fuels, thereby resulting in low parasitic power consumption and high percentage CO2 removal efficiency.

[0017] These and other objectives are obtained by the system according to claim 1 and the method according to claim 13.

[0018] A carbon capture system for an LNG fueled power plant comprising a LNG tank, a LNG gasification system, a gas engine, a CO2 adsorber, wherein: the LNG tank comprises a LNG outlet in fluid communication with a LNG main inlet of the LNG gasification system, the LNG gasification system comprises a main NG outlet in fluid communication with a NG inlet to the gas engine which comprises an exhaust gas outlet that is in fluid communication with a CO2 adsorber inlet of the CO2 adsorber in adsorption mode which has a CO2 depleted exhaust outlet, the CO2 adsorber in desorption mode comprises an CO2 desorber inlet in fluid communication with a NG outlet of the LNG gasification system, and a CO2 desorber outlet, the CO2 desorber outlet is in fluid communication with a first heat exchanger of the LNG gasification system for cooling by heat exchange with the LNG, the LNG tank is via the LNG gasification system in pressure communication with the CO2 desorber outlet such that CO2 desorbed from the CO2 adsorber in desorption mode is pressurized by the pressure of the LNG tank.

[0019] The carbon capture system is designed to cool and pressurize the captured CO2 using the cold of the LNG and the pressure stored LNG, to obtain liquified CO2. Further, the system is designed to form an integrated part of the LNG gasification system and a gas engine.

[0020] In one aspect of the carbon capture system the LNG tank is equipped with a pressurization loop comprising a heater. Here the system may comprise a LNG tank with a tank outlet in fluid communication with the LNG main inlet and with a pressure build up loop, to control the pressure of the tank, comprising a loop inlet in fluid communication with the tank outlet a vaporizer and a loop outlet in fluid communication with the LNG tank. Alternatively, the pressure of the LNG tank is controlled by an external system.

[0021] The operational pressure of the LNG tank may be above 5 bar, from 8 bar to 24 bar, from 10-20 bar in most cases.

[0022] In one aspect of the carbon capture system the system comprises at least two CO2 adsorbers, one CO2 adsorber in adsorption mode and one CO2 adsorber in desorption mode.

[0023] In a further embodiment of the carbon capture system

[0024] - the LNG main inlet is in fluid communication with an LNG inlet of a LNG evaporator which comprises the NG outlet,

[0025] - the NG outlet is in fluid communication with the NG inlet,

[0026] - the gas engine comprises an oxygen source inlet, - the exhaust gas outlet is in fluid communication with a separator inlet of a water separator comprising a water outlet and a dry exhaust gas outlet in fluid communication with the CO2 adsorber inlet to the CO2 adsorber in adsorption mode.

[0027] In a further aspect of the carbon capture system the system comprises

[0028] - an air cooler downstream the gas engine and upstream the water separator and the CO2 adsorber in adsorption mode.

[0029] In another aspect of the carbon capture system the system comprises,

[0030] - a second heat exchanger for cooling the exhaust gas with a second heat exchanger first inlet in fluid communication with the exhaust gas outlet and a second heat exchanger first outlet in fluid communication with the separator inlet, a second heat exchanger second inlet in fluid communication with the NG outlet and a second heat exchanger second outlet in fluid communication with the NG inlet, such that the exhaust gas from the gas engine is cooled by heat exchange with the NG stream.

[0031] Further, in one aspect the CO2 adsorber inlet of the CO2 adsorber in desorption mode is in fluid communication with the second heat exchanger second outlet of the second heat exchanger. Thereby, the NG that has been heated through heat exchange with the exhaust is fed into the CO2 adsorber in desorption mode to desorb the adsorbed CO2 into the NG stream.

[0032] In yet another aspect of the carbon capture system

[0033] - the first heat exchanger for cooling the desorbed CO2 comprises a first heat exchanger first inlet in fluid communication with the CO2 adsorber outlet and a first heat exchanger first outlet, a first heat exchanger second inlet in fluid communication with the LNG main inlet and a first heat exchanger second outlet in fluid communication with the LNG inlet. Thereby, the desorbed CO2 can be cooled by heat exchange with the LNG utilizing the available cryogenic source.

[0034] In a further aspect the carbon capture system comprises:

[0035] - a third heat exchanger for further cooling the desorbed CO2 with a third heat exchanger first inlet in fluid communication with the first heat exchanger first outlet and a third heat exchanger first outlet, a third heat exchanger second inlet and a third heat exchanger second outlet in fluid communication with the main NG outlet,

[0036] - a first liquid CO2 separator with an first CO2 separator inlet in fluid communication with the third heat exchanger first outlet, a first CO2 separator gas outlet in fluid communication with the third heat exchanger second inlet and a first CO2 separator liquid outlet in fluid communication with a liquid CO2 storage tank inlet of

[0037] - a liquid CO2 storage tank with a liquid CO2 outlet and a liquid CO2 storage tank gas outlet in fluid communication with the main NG outlet, - a second air cooler arranged between the CO2 desorber outlet and the first heat exchanger first inlet.

[0038] In the third heat exchanger the combined CO2 and NG stream from first heat exchanger is further cooled by heat exchange with the separated NG stream obtained by separation by liquification of the CO2.

[0039] In yet another aspect of the carbon capture system the CO2 adsorber in adsorption mode and the CO2 adsorber in desorption mode comprise an adsorber selected from molecular sieves, zeolites, activated alumina, silica gel, polymeric adsorbents or other kind of adsorbents, preferably molecular sieves that can adsorb and desorb CO2.

[0040] In one aspect of the carbon capture system the position of the CO2 adsorber in adsorption mode and the CO2 adsorber in desorption mode are interchangeable such that the CO2 adsorber that was in adsorption mode is in desorption mode and the CO2 adsorber that was in desorption mode is in adsorption mode.

[0041] The term “position” is used here to refer to the position in terms of fluid connections to other elements of the system.

[0042] In a further aspect of the carbon capture system an additional water removal unit is arranged in the gas stream between the water separator, and the CO2 adsorber in adsorption mode.

[0043] Removing water from the exhaust gas upstream the adsorber in adsorption mode is beneficial for the efficiency of the adsorption.

[0044] In yet another aspect of the carbon capture system, the system further comprises compressor arranged to compress the desorbed gas.

[0045] In another aspect the present solution discloses a method for LNG combustion and carbon capture, wherein the method comprises

[0046] - providing a LNG stream

[0047] - gasifying the LNG stream by heating to obtain a gasified NG stream

[0048] - combusting the gasified NG stream to obtain exhaust gas stream

[0049] - adsorbing CO2 from the exhaust gas stream to obtain a CO2 depleted exhaust gas stream

[0050] - desorbing CO2 with a pressurized and heated gasified NG stream to obtain a combined NG and CO2 stream

[0051] - cooling the combined NG and CO2 stream by heat exchange with the LNG stream to obtain a cooled combined NG and CO2 stream

[0052] - separating liquid CO2 from the cooled combined NG and CO2 stream. In one aspect of the method, the method further comprises

[0053] - cooling the exhaust gas stream by heat exchange with the gasified NG stream to obtain a cooled exhaust gas stream;

[0054] - separating water from the cooled exhaust gas stream to obtain a dry exhaust gas stream, and wherein the step of

[0055] - adsorbing CO2 from the exhaust gas stream to obtain a CO2 depleted exhaust gas stream, is performed on the dry exhaust gas stream.

[0056] In another aspect of the method separating liquid CO2 from the cooled combined NG and CO2 stream provides a CO2 depleted NG stream and the method comprises combusting the CO2 depleted NG stream.

[0057] In a further aspect the method comprises heating the CO2 depleted NG stream by heat exchange with the cooled combined NG and CO2 stream.

[0058] In yet another aspect of the method CO2 in the CO2 depleted NG stream after the combustion is adsorbed when adsorbing CO2 from the exhaust gas stream. Thereby, any CO2 remaining in the CO2 depleted gas does not combustion but is recircled to the absorption step.

[0059] In a further aspect of the method the adsorption and desorption are performed using molecular sieves.

[0060] In another aspect of the method it comprises pressurizing the cooled combined NG and CO2 stream by communicating with a LNG tank at higher pressure before separating liquid CO2 from the cooled combined NG and CO2 stream. Alternatively, the method may comprise pressurizing the cooled combined NG and CO2 stream by a compressor before separating liquid CO2 from the cooled combined NG and CO2 stream.

[0061] In one aspect of the carbon capture system and the method the heat for the adsorption comes from the exhaust gas.

[0062] In an embodiment of the carbon capture system and method, the system comprises gas inlet to the CO2 adsorber in desorption mode. The gas can be provided as an external gas source and the gas can be nitrogen, hydrocarbon gases or inert gases The gas is supplied as an alternative stream for desorption of the adsorbed CO2.

[0063] In one aspect of the carbon capture system and method, wherein the cold source for the desorption could be provided by an external refrigeration system.

[0064] The term “LNG” is herein used to refer to liquid / liquefied natural gas. The term “NG” as used herein refers to natural gas in gas phase.

[0065] The term “gas engine” is used herein to refer to any type of equipment that combusts fuel including NG. Accordingly, the gas engine may include alone or in combination turbines, boilers, fired equipment or other equipment that burns fuel and generate heat.

[0066] Carbon capture system may be used with LNG as the only fuel source, but the system could also be used other fuels or mixtures of fuels, wherein at least one of the fuels is stored in a cryogenic tankers, such as, but not limited to, LNG, liquified biomethane, ethane, liquid hydrogen.

[0067] Here the LNG, or any other cryogenic fluid, could be mixed with other fuels such as, but not limited to, diesel, LGP, propane, ammonia, hydrogen, non-cryogenic natural gas, HFO, and / or bunker oil.

[0068] The disclosed system may include one or more heat exchangers, these heat exchangers can be direct heat exchangers wherein the two fluids via a heat exchanging barrier are brought in heat exchanging contact. The heat exchangers may also be indirect heat exchangers wherein the heat passes via an intermediate fluid between the two fluid streams being heat exchanged. Accordingly, the term “heat exchanger” is used herein to refer to both direct and indirect heat exchangers.

[0069] In a carbon capture system according to the present disclosure the CO2 adsorber in adsorption mode and the CO2 adsorber in desorption mode comprise a reversible CO2 adsorber, that adsorbs the CO2 and from which the adsorbed CO2 can be desorbed. Applicable adsorbers can be selected from molecular sieves, zeolites, activated alumina, silica gel, polymeric adsorbents or other kind of adsorbents. In one embodiment the absorber is molecular sieves that can adsorb and desorb CO2. The use of an adsorber such as molecular sieves allows for the use of the cold stream to exchange heat with a very concentrated CO2 stream (above 80 % CO2 such as about 90%, while the CO2 composition of a exhaust gas is about 5 to 10%), therefore optimizing the use of the cold.

[0070] Typically, in industrial processes, molecular sieves are employed for separation and purification tasks. Their unique ability to selectively adsorb molecules based on size and shape allows them to remove unwanted components from gases and liquids. This makes them valuable in various sectors, including petrochemical refining, natural gas processing, and air purification. They are also used for desiccation, removing moisture from products and processes to prevent corrosion, improve product quality, and extend shelf life. Molecular sieves designed for adsorption of CO2 are commercially available. By using a NG stream for the desorption of CO2, the separation of the CO2 from the NG by a cryogenic process is possible.

[0071] The method uses the LNG (or a cryogenic fuel) as a source of cold, since it needs to be gasified to be used as a fuel.

[0072] This design considers available fuel gas as the source of cold for the cryogenic carbon capture avoiding the use of any external system, avoiding equipment cost and relevant parasitic energy consumption.

[0073] The design uses LNG storage tank pressure to obtain captured CO2 in liquid phase.

[0074] The system design can provide for the pressurization of the CO2 before entering the cryogenic separator, so the captured CO2 can be in a liquid phase. Such pressurization is due to the piping communication between the LNG storage tank (that is on a pressure high enough to have the CO2 in liquid phase) and the adsorber that is in desorption mode, as well as the CO2 cryogenic separator and CO2 storage tank. The pressure in the LNG storage tank is controlled by a pressure build up unit that vaporizes a certain amount of LNG and send back to the tank to increase the pressure, whenever a low pressure setpoint is reached.

[0075] The design uses exhaust gas heat for regeneration of molecular sieve, therefore there is no parasite energy consumption. The use of exhaust gas heat allows fast cycle of molecular sieve, therefore increases the capacity of the equipment, make it feasible to remove more CO2 from the natural gas than solutions of carbon capture using amines or membranes.

[0076] The system uses a combination of adsorption and cryogenic technologies for post combustion carbon capture, considering that the cold source for the cryogenic part comes from the vaporization of a cryogenic fuel, such as LNG, ensuring that there’s no relevant parasitic energy in the carbon capture process and that there’s no refrigerant that is not required to typical vaporization systems.

[0077] The system uses the vaporized fuel gas to regenerate the molecular sieves, therefore any CO2 not separated by the cryogenic section loops back into the fuel consumer (i.e. engine) improving the percentage of CO2 captured.

[0078] The system can pressurize the regenerated CO2, using the pressure from the fuel, ensuring that the CO2 resulting from the cryogenic carbon capture is on liquid phase, facilitating its logistics.

[0079] The fact that the captured CO2 is in liquid phase not only improve the logistics, but also reduce significantly (up to 70%) the energy required to pressurize it to be injected into reservoirs for carbon capture storage / sequestration or for enhanced oil recovery (EOR), for instance. Brief description of the drawings

[0080] The present invention will be described in further detail with reference to the drawings that illustrate embodiments of thereof.

[0081] Figure 1 shows a schematic representation of a system comprising the inventive system.

[0082] Figure 2 illustrates schematically the steps of the method according to the invention.

[0083] Principal description of the invention

[0084] Figure 1 illustrates schematically the system 1 and the method. The Figure includes optional features and embodiments of the present invention may not include all the illustrated features, in Figure 1 a main LNG stream 11 is partly obtained directly from an LNG tank 10. A mechanism to increase and control the pressure in the LNG tank 10 uses a vaporization loop 13, 14,15 through which LNG is passed from the tank 10 through a vaporization heater 14 and back into the tank 10. Additionally, the tank will have a refilling inlet (not shown).

[0085] A part of the LNG stream from the LNG tank 10 is passed as stream 105 via a heat exchanger 100 before as a return stream 107 of LNG being combined with the main LNG stream 11. The stream 105 is being used as a cooling fluid in a heat exchanger 100 for cooling desorbed CO2. The heat exchanger 100 is run counter-current.

[0086] The combined LNG stream enters the inlet 21 of a NG heater 20 wherein the LNG is heated and transformed to NG that leaves through the heater outlet 23. The obtained NG stream can be directly transported to the inlet 31 of the gas engine 30 via direct NG conduit 25 or may be used for cooling the exhaust or desorbing the CO2 before forming part of a main NG stream 37. In the gas engine 30 the NG is combusted through reaction with an oxygen containing stream added through inlet 35 creating an exhaust stream that leaves the engine through outlet 33. The combustion results in a heated exhaust gas stream.

[0087] The hot exhaust gas is fed through exhaust air cooler inlet 41 to exhaust air cooler 40 to be cooled down. The air cooled exhaust passes via air cooler outlet 43 to water separator inlet 51. The cooled exhaust gas is dehydrated in the water separator 50. The water separated out is removed through water outlet 57 and dry cooled exhaust is passed through dry exhaust gas outlet 53. The dry exhaust gas enters into the adsorber 60 through absorber inlet 61. In the absorber CO2 will be adsorbed and the exhaust CO2 depleted stream leaves the system through outlet 63.

[0088] For the regeneration of the adsorber 260, part of the NG stream, passed via 85 is heated with part of the hot exhaust gas fed via 81, in the exhaust heat exchanger 80. A NG control valve 88 and an exhaust control valve 82 control the amount of heat that is exchanged in the exhaust heat exchanger 80. After having passed through the exhaust heat exchanger the cooled exhaust is via outlet 83 returned to the exhaust stream. In the illustrated embodiment it is returned upstream the exhaust air cooler. The figure illustrates that the heat exchanger 80 is run co-currently however other configurations like counter-current may be applied.

[0089] The NG regeneration stream from the outlet 87 of the exhaust heat exchanger 80 possibly combined with additional NG directly from the heater outlet 23, is fed via desorber inlet 265 into the absorber 260 in desorption mode for regeneration of the absorber. The NG gas adsorbs the CO2 and leaves the absorber 260 in desorption mode as a CO2 rich NG regeneration stream via desorber outlet 267. Via second air cooler inlet 91 the CO2 rich NG regeneration stream is fed to second air cooler 90. Here the stream is cooled down . From the second air cooler outlet 93 the stream is passed through the inlet 101 of the first heat exchanger where it is cooled down ever further. The cooled CO2 rich NG stream leaves through outlet 103 of the first heat exchanger 100 and is passed through inlet 111 into the third heat exchanger 110 for further cooling. The third heat exchanger is operated counter currently and the cooling is provided by a CO2 depleted gas stream from cryogenic CO2 separator 120 that passes in through inlet 115 and out through outlet 117. The CO2 depleted NG is joint with the other NG streams into the main NG stream 37. The further cooled CO2 rich NG stream leaves the third heat exchanger through outlet 113. Via separator inlet 121 the further cooled CO2 rich NG regeneration stream enters into the cryogenic separator 120, where the captured CO2 in liquid phase leaves through separator outlet 123 and goes to the liquid CO2 storage tank 130 via inlet 131. Eventual CO2 storage tank boil of gas (BOG) can be removed through outlet 135 joins the main NG stream 37 looping back again as fuel of the gas engine 30. Produced liquid CO2 can be removed through tank outlet 133. The gas phase from the cryogenic separator 120 is removed through outlet 125 and passes through the third heat exchanger 110.

[0090] Figure 2 illustrates the main steps of one embodiment of the method. Here the steps on the left-hand side are the LNG combustion and carbon adsorption steps the selected adsorber being molecular sieves. The steps on the right are the carbon desorption and separation steps. The arrows therebetween illustrate the exchange of heat / cold between the process steps in the sequences. In that heat for the gasification is provided from the hot exhaust and from the NG + CO2 stream from the desorber thereby cooling the exhaust and the NG + CO2 stream. The heated NG stream used in the desorption is obtain as part of the gasifying of LNG and the gas remaining when liquid CO2 is separated out is forwarded to the combusting. List of reference numbers:

[0091] 1 carbon capture system for an LNG fueled power plant

[0092] 10 LNG tank

[0093] 11 LNG main inlet

[0094] 13 LNG loop inlet

[0095] 14 vaporization heater

[0096] 15 LNG loop outlet

[0097] 17 LNG outlet

[0098] 20 NG heater

[0099] 21 NG heater inlet

[0100] 23 NG heater outlet

[0101] 25 direct NG conduit

[0102] 30 gas engine

[0103] 31 NG inlet

[0104] 33 exhaust gas outlet

[0105] 35 oxygen / air inlet

[0106] 37 main NG outlet

[0107] 40 exhaust air cooler / first air cooler

[0108] 41 exhaust air cooler inlet

[0109] 43 exhaust air cooler outlet

[0110] 50 water separator

[0111] 51 water separator inlet

[0112] 53 dry exhaust gas outlet

[0113] 57 water outlet

[0114] 60 CO2 adsorber in adsorption mode

[0115] 61 CO2 adsorber inlet

[0116] 63 CO2 depleted exhaust outlet

[0117] 80 exhaust heat exchanger / second heat exchanger

[0118] 81 second heat exchanger first inlet

[0119] 82 exhaust control valve

[0120] 83 second heat exchanger first outlet

[0121] 85 second heat exchanger second inlet

[0122] 87 second heat exchanger second outlet

[0123] 88 NG control valve

[0124] 90 second air cooler

[0125] 91 second air cooler inlet

[0126] 93 second air cooler outlet

[0127] 100 first heat exchanger

[0128] 101 first heat exchanger first inlet

[0129] 103 first heat exchanger first outlet

[0130] 105 first heat exchanger second inlet

[0131] 107 first heat exchanger second outlet 110 third heat exchanger

[0132] 111 third heat exchanger first inlet

[0133] 113 third heat exchanger first outlet

[0134] 115 third heat exchanger second inlet

[0135] 117 third heat exchanger second outlet

[0136] 120 first liquid CO2 separator

[0137] 121 first CO2 separator inlet

[0138] 123 first CO2 separator liquid outlet

[0139] 125 first CO2 separator gas outlet

[0140] 130 liquid CO2 storage tank

[0141] 131 liquid CO2 storage tank inlet

[0142] 133 liquid CO2 outlet

[0143] 135 liquid CO2 storage tank gas outlet

[0144] 260 CO2 adsorber in desorption mode

[0145] 265 CO2 desorber inlet

[0146] 267 CO2 desorber outlet

Claims

CLAIMS1. A carbon capture system for an LNG fueled power plant (1) comprising a LNG tank (10), a LNG gasification system (20,80,100,110,130), a gas engine (30), a CO2 adsorber (60,260), wherein:- the LNG tank (10) comprises a LNG outlet (17) in fluid communication with a LNG main inlet (11) of the LNG gasification system (20,80, 100,110,130),- the LNG gasification system (20,80,100,110,130) comprises a main NG outlet (37) in fluid communication with a NG inlet (31) to the gas engine (30) which comprises an exhaust gas outlet (33) that is in fluid communication with a CO2 adsorber inlet (61) of the CO2 adsorber (60) in adsorption mode which has a CO2 depleted exhaust outlet (63),- the CO2 adsorber (260) in desorption mode comprises an CO2 desorber inlet (265) in fluid communication with a NG outlet (23) of the LNG gasification system, and a CO2 desorber outlet (267),- the CO2 desorber outlet (267) is in fluid communication with a first heat exchanger (100) of the LNG gasification system for cooling by heat exchange with the LNG,- the LNG tank (10) is via the LNG gasification system in pressure communication with the CO2 desorber outlet (267) such that CO2 desorbed from the CO2 adsorber (260) in desorption mode is pressurized by the pressure of the LNG tank (10).

2. Carbon capture system according to claim 1, wherein the LNG tank (10) is equipped with a pressurization loop (13,15) comprising a heater (14).

3. Carbon capture system according to claim 1 or 2, wherein the system comprises at least two CO2 adsorbers (60, 260), one CO2 adsorber (60) in adsorption mode and one CO2 adsorber (260) in desorption mode.

4. Carbon capture system according to anyone of the preceding claims, wherein- the LNG main inlet (11) is in fluid communication with an LNG inlet (21) of a LNG evaporator (20) which comprises the NG outlet (23),- the NG outlet (23) is in fluid communication with the NG inlet (31)- the gas engine (30) comprises a oxygen source inlet (35),- the exhaust gas outlet (33) is in fluid communication with a separator inlet (51) of a water separator (50) comprising a water outlet (57) and an dry exhaust gas outlet (53) in fluid communication with the CO2 adsorber inlet (61) to theCO2adsorber (60) in adsorption mode.

5. Carbon capture system according to claim 4, wherein the system comprises- an air cooler (40) downstream the gas engine (30) and upstream the water separator (50) and the CO2adsorber (60) in adsorption mode.

6. Carbon capture system according to claim 4 or 5, wherein the system comprises,- a second heat exchanger (80) for cooling the exhaust gas with a second heat exchanger first inlet (81) in fluid communication with the exhaust gas outlet (33) and a second heat exchanger first outlet (83) in fluid communication with the separator inlet (51), a second heat exchanger second inlet (85) in fluid communication with the NG outlet (23) and a second heat exchanger second outlet (87) in fluid communication with the NG inlet (31),- the CO2 adsorber inlet (265) of the CO2 adsorber (260) in desorption mode is in fluid communication with the second heat exchanger second outlet (87) of the second heat exchanger (80), .

7. Carbon capture system according to claim 4, 5 or 6, wherein- the first heat exchanger (100) for cooling the desorbed CO2 comprises a first heat exchanger first inlet (101) in fluid communication with the CO2 adsorber outlet (267) and a first heat exchanger first outlet (103), a first heat exchanger second inlet (105) in fluid communication with the LNG main inlet (11) and a first heat exchanger second outlet (107) in fluid communication with the LNG inlet (21).

8. Carbon capture system according to claim 7, wherein the system comprises- a third heat exchanger (110) for further cooling the desorbed CO2 with a third heat exchanger first inlet (111) in fluid communication with the first heat exchanger first outlet (103) and a third heat exchanger first outlet (113), a third heat exchanger second inlet (115) and a third heat exchanger second outlet (117) in fluid communication with the main NG outlet (37),- a first liquid CO2 separator (120) with an first CO2 separator inlet (121) in fluid communication with the third heat exchanger first outlet (113), a first CO2 separator gas outlet (125) in fluid communication with the third heat exchanger second inlet (115) and a first CO2 separator liquid outlet (123) in fluid communication with a liquid CO2 storage tank inlet (131) of- a liquid CO2 storage tank (130) with a liquid CO2 outlet (133) and a liquid CO2 storage tank gas outlet (135) in fluid communication with the main NG outlet (37),- a second air cooler (90) arranged between the CO2 desorber outlet (267) and the first heat exchanger first inlet (101).

9. Carbon capture system according to any one of the preceding claims, wherein the CO2 adsorber (60) in adsorption mode and the CO2 adsorber (260) in desorption mode comprise an adsorber selected from molecular sieves, zeolites, activated alumina, silica gel, polymeric adsorbents or other kind of adsorbents, preferably molecular sieves that can adsorb and desorb CO2.

10. Carbon capture system according to any one of the preceding claims, wherein the position of the CO2 adsorber (60) in adsorption mode and the CO2 adsorber (260) in desorption mode are interchangeable such that the CO2 adsorber (60) that was in adsorption mode is in desorption mode and the CO2 adsorber (260) that was in desorption mode is in adsorption mode.

11. Carbon capture system according to any one of the preceding claims, wherein an additional water removal unit is arranged in the gas stream between the water separator (50), and the CO2 adsorber (60) in adsorption mode.

12. Carbon capture system according to any one of the preceding claims, wherein the system further comprises a compressor arranged to compress the desorbed gas.

13. Method for LNG combustion and carbon capture, wherein the method comprises- providing a LNG stream- gasifying the LNG stream by heating to obtain a gasified NG stream- combusting the gasified NG stream to obtain exhaust gas stream- adsorbing CO2 from the exhaust gas stream to obtain a CO2 depleted exhaust gas stream- desorbing CO2 with a pressurized and heated gasified NG stream to obtain a combined NG and CO2 stream- cooling the combined NG and CO2 stream by heat exchange with the LNG stream to obtain a cooled combined NG and CO2 stream- separating liquid CO2 from the cooled combined NG and CO2 stream.

14. Method according to claim 13, wherein the method further comprises- cooling the exhaust gas stream by heat exchange with the gasified NG stream to obtain a cooled exhaust gas stream;- separating water from the cooled exhaust gas stream to obtain a dry exhaust gas stream, and wherein the step of- adsorbing CO2 from the exhaust gas stream to obtain a CO2 depleted exhaust gas stream, is performed on the dry exhaust gas stream.

15. Method according to claim 13 or 14, wherein separating liquid CO2 from the cooled combined NG and CO2 stream provides a CO2 depleted NG stream and the method comprises combusting the CO2 depleted NG stream.

16. Method according to any one of the claims 13-15, wherein the method comprises heating the CO2 depleted NG stream by heat exchange with the cooled combined NG and CO2 stream.

17. Method according to any one of the claims 13-16, wherein CO2 in the CO2 depleted NG stream after the combustion is adsorbed when adsorbing CO2 from the exhaust gas stream.

18. Method according to any one of the claims 13 to 17, wherein the adsorption and desorption is performed using molecular sieves.

19. Method according to any one of the claims 13 to 18, wherein the method comprises pressurizing the cooled combined NG and CO2 stream by communicating with a LNG tank at higher pressure before separating liquid CO2 from the cooled combined NG and CO2 stream.

20. Method according to any one of the claims 13 to 18, wherein the method comprises pressurizing the cooled combined NG and CO2 stream by a compressor before separating liquid CO2 from the cooled combined NG and CO2 stream.

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