WO2025066493A1 - Gas capture and storage system and method - Google Patents

Abstract

The present application discloses a gas capture and storage system and a method. The gas capture and storage system of the present application comprises: an absorption unit, a desorption unit, and a gas transfer unit. A carbon-containing flue gas is fed into the absorption unit, and comes into contact with an absorption liquid in the absorption unit to form a first solution, and the first solution is fed into the desorption unit. A desorption gas is fed into the desorption unit by means of the gas transfer unit, and comes into contact with the first solution to complete desorption of at least part of carbon dioxide to form a second solution, and the second solution is fed into the absorption unit.

Description

A gas capture storage system and method

This application claims the priority of the Chinese patent application filed with the China Patent Office on September 28, 2023, with application number 202311284358.7 and invention name “A Gas Capture and Storage System and Method”, the entire contents of which are incorporated by reference into this application.

Technical Field

The present application relates to but is not limited to the field of ship exhaust purification.

Background Art

Ship carbon capture and storage post-processing technology has become an important technical route for ship emissions due to its advantages such as large emission reduction capabilities, good matching with ship operating conditions, and economy.

Technical Solutions

In a first aspect, an embodiment of the present application provides a gas capture and storage system, comprising:

An absorption unit, wherein the absorption unit has a first inlet and a first outlet, the carbon-containing flue gas is fed into the absorption unit from the first inlet, the carbon-containing flue gas contains carbon dioxide, the carbon-containing flue gas contacts with the absorption liquid in the absorption unit to form a first solution, and the first solution is fed out from the first outlet;

A desorption unit, wherein the desorption unit has a second inlet, and the first solution delivered from the first outlet is delivered to the desorption unit from the second inlet;

A gas transfer unit, wherein the gas transfer unit is used to feed a desorption gas into the desorption unit, wherein the desorption gas contacts the first solution to complete the desorption of at least part of the carbon dioxide to form a second solution, and the second solution is fed from the desorption unit to the absorption unit.

Optionally, a circulation unit is further included, wherein the circulation unit includes a first circulation pump, wherein an inlet of the first circulation pump is connected to the first outlet, and an outlet of the first circulation pump is connected to the second inlet.

Optionally, the circulation unit includes a second circulation pump, the absorption unit has a third inlet, the desorption unit has a second outlet, the inlet of the second circulation pump is connected to the second outlet, and the outlet of the second circulation pump is connected to the third inlet.

Optionally, the circulation unit includes a heat exchanger, and the heat exchanger is connected to the outlet of the first circulation pump and the outlet of the second circulation pump respectively.

Optionally, the heat exchanger has a first heat exchange outlet, which is connected to the second inlet; the heat exchanger has a second heat exchange outlet, which is connected to the third inlet.

Optionally, the circulation unit includes a first heater, and the first heater is arranged between the first heat exchange outlet and the second inlet.

Optionally, the circulation unit includes a cooler, and the cooler is arranged between the second heat exchange outlet and the third inlet.

Optionally, the gas transfer unit comprises a membrane separator, the desorption unit has a third outlet, and the inlet of the membrane separator is connected to the third outlet.

Optionally, the gas transfer unit includes a condenser, which is arranged between the membrane separator and the third outlet.

Optionally, the gas transfer unit comprises a second heater, the desorption unit has a fourth inlet, and the second heater is arranged between the membrane separator and the fourth inlet.

Optionally, the gas delivery unit has a fifth inlet for introducing desorption gas.

In a second aspect, the present application also provides a gas capture method, comprising:

The carbon-containing flue gas is sent to an absorption unit, wherein the absorption unit contains an absorption liquid, the carbon-containing flue gas contains carbon dioxide, and the absorption liquid forms a first solution after contacting the carbon-containing flue gas;

The first solution is fed into a desorption unit, and a gas transmission unit feeds a desorption gas into the desorption unit to desorb carbon dioxide in the first solution;

The first solution after desorption forms a second solution, and the second solution is sent from the desorption unit to the absorption unit.

Optionally, the absorption unit has a first air pressure, and the pressure range of the first air pressure is 0.8 to 1.2 bar.

Optionally, the absorption unit has a first temperature, and the first temperature ranges from 30 to 40°C.

Optionally, the desorption unit has a second gas pressure, and the pressure range of the second gas pressure is 0.8 to 1.2 bar.

Optionally, the desorption unit has a second temperature, and the second temperature ranges from 80 to 90°C.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

FIG1 is a schematic diagram of the gas stripping desorption principle of the double membrane theory;

FIG2 is a schematic diagram of the structure of a gas capture and storage system in an embodiment of the present application;

FIG3 is a schematic flow chart of a gas capture method in an embodiment of the present application.

DETAILED DESCRIPTION

The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the embodiments of the present application and the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application. In addition, in the description of the present application, the term "including" means "including but not limited to". The terms first, second, third, etc. are used only as markings, and no numerical requirements or order are imposed. Various embodiments of the present application may exist in the form of a range; it should be understood that the description in the form of a range is only for convenience and simplicity, and should not be understood as a hard limit to the scope of the present application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single values within the range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the numbered range, such as 1, 2, 3, 4, 5 and 6, which are applicable regardless of the range. Additionally, whenever a numerical range is indicated herein, it is meant to include any cited numeral (fractional or integral) within the indicated range.

Basic principle of gas stripping desorption of _CO2 Gas stripping desorption is based on the double membrane theory, as shown in Figure 1. The double membrane theory believes that there is a phase interface between the gas and liquid phases in contact with each other, with a gas film and a liquid film on both sides. During the desorption process, the concentration gradient between the gas film and the liquid film is the driving force for mass transfer of _CO2 between the gas phase and the liquid phase. Due to the different _CO2 partial pressures in the gas and liquid phases, under the impetus of the pressure difference, _CO2 reaches the liquid film by molecular diffusion, and then enters the gas film through the phase interface, thereby desorbing _CO2 from the absorbed rich liquid. Therefore, nitrogen or solvent vapor without solute is used as a carrier gas to blow _CO2 from the absorbed liquid. The gas phase _CO2 partial pressure is reduced, thereby increasing the mass transfer driving force of the desorption process, so that _CO2 can be continuously desorbed from the absorbent rich liquid. The advantage of gas lift desorption of _CO2 is that it requires low energy consumption, promotes the _CO2 desorption reaction rate, reduces the _CO2 desorption reaction temperature, thereby reducing the energy consumption of the _CO2 desorption process and reducing the system operation cost; and the greater the amount of gas introduced, the greater the amount of _CO2 desorbed. However, due to the limitations of the ship's operating environment, the captured and desorbed _CO2 needs to be stored in the ship's storage tank and subsequently transported and utilized. This process still has high requirements for the purity of _CO2 . Ship carbon capture and storage post-processing technology has become an important technical route for ship emissions due to its advantages such as large emission reduction, good matching with ship operating conditions, and economy. Although this technology can achieve large-scale carbon emission reduction, there is a problem of high system desorption energy consumption, which is difficult to meet the application needs of actual ships.

In order to solve the problems existing in the prior art, the present application provides a gas capture and storage system, as shown in Figure 2, comprising: an absorption unit 100, the absorption unit 100 has a first inlet 101 and a first outlet 102, the carbon-containing flue gas is fed into the absorption unit 100 from the first inlet 101, the carbon-containing flue gas contains carbon dioxide, the carbon-containing flue gas contacts with the absorption liquid in the absorption unit 100 to form a first solution, and the first solution is sent out from the first outlet 102; a desorption unit 200, the desorption unit 200 has a second inlet 201, the first solution sent out from the first outlet 102 is fed into the desorption unit 200 from the second inlet 201; a gas transfer unit 300, the gas transfer unit 300 is used to feed desorption gas into the desorption unit 200, the desorption gas contacts with the first solution, completes the desorption of at least part of the carbon dioxide, forms a second solution, and the second solution is fed from the desorption unit 200 into the absorption unit 100. The gas capture and storage system of the present application utilizes the desorption gas to reduce the partial pressure of carbon dioxide in the desorption system while ensuring the complete functionality of the ship power carbon capture system, thereby promoting the desorption reaction of carbon dioxide, reducing the regeneration energy consumption of the desorption system, and reducing the system operating costs, which can further promote the application of carbon capture technology in the field of ship carbon emission reduction.

In some embodiments, the gas capture storage system further comprises a circulation unit 400 , wherein the circulation unit 400 comprises a first circulation pump 401 , wherein an inlet of the first circulation pump 401 is connected to the first outlet 102 and the second inlet 201 .

In some embodiments, the main structure of the absorption unit 100 is an absorption tower, which has a first inlet 101 for introducing carbon-containing flue gas. In some embodiments, the first inlet 101 is located below the absorption tower, and the carbon-containing flue gas is introduced into the bottom of the absorption tower from the first inlet 101, and the carbon-containing flue gas flows from bottom to top in the absorption tower.

In some implementations, the absorption unit 100 has a third inlet 103. In some embodiments, the third The inlet is located above the absorption tower, and the absorption liquid is sprayed from the absorption tower from top to bottom. The carbon-containing flue gas enters from the bottom of the absorption tower and flows upward to complete the adsorption of the carbon-containing flue gas by the absorption liquid, wherein the carbon dioxide in the carbon-containing flue gas is adsorbed by the absorption liquid to form a first solution (rich liquid).

In some implementations, fillers may be arranged in the absorption tower to increase the contact area between the absorption liquid and the carbon-containing flue gas and the adsorption efficiency. In some specific embodiments, the fillers may be selected from one or more of corrugated plates, ceramic fillers, and metal fillers. The fillers may be bulk or structured fillers.

In some embodiments, the form, size, model and specification of the filler can be selected based on parameters such as the actual _CO2 removal efficiency, pressure drop requirements in the absorption tower, liquid flooding rate requirements and operating conditions.

In some embodiments, the absorption liquid includes an organic amine solution, and single or mixed organic amine solutions such as MEA (ethanolamine), MDEA (2-methyl-diethylaminoethanolamine), and DEA (diethanolamine) may be used.

In some embodiments, after the carbon-containing flue gas is adsorbed by the absorption liquid, the clean flue gas is discharged from the top of the absorption tower.

In some embodiments, the main structure of the desorption unit 200 is a desorption tower 210, and the first solution (rich liquid, absorption liquid that has absorbed _CO2 ) in the desorption tower 210 is sent into the desorption tower 210 under the action of a pump group.

In some embodiments, a second inlet 201 is provided on the desorption tower 210, and the first solution is fed into the desorption tower from the second inlet 201. In some embodiments, the second inlet 201 is located above the desorption tower 210, and the first solution is fed into the desorption tower 210 from the top of the desorption tower 210.

In some embodiments, a desorption gas is simultaneously introduced into the desorption tower 210, and the desorption gas may be nitrogen or solvent vapor without solute. In some embodiments, the desorption tower 210 has a fourth inlet 204, and the desorption gas is introduced into the desorption tower 210 through the fourth inlet 204. In some specific embodiments, the fourth inlet 204 is disposed inside the desorption tower 210. The rich liquid is desorbed in the desorption tower 210, and CO ₂ is released again to form a second solution (lean liquid).

In some embodiments, the desorption tower 210 has a second outlet 202 . In some embodiments, the second outlet 202 is located at the bottom of the desorption tower 210 , and the second solution is fed into the absorption tower 110 through the second outlet 202 .

In some embodiments, the desorption tower 210 has a third outlet 203. In some embodiments, the third outlet 203 is located at the top of the desorption tower 210. The third outlet 203 is used to send out the product gas located in the desorption tower 210. In some specific application examples, the product gas of the third outlet 203 at the top of the desorption tower 210 includes CO ₂ , N 2 and a small amount of water vapor are fed into the gas transfer unit 300 .

In some embodiments, the gas transfer unit 300 includes a membrane separator 301, the inlet of the membrane separator 301 is connected to the third outlet 203, and the membrane separator 301 is a nitrogen membrane separator in some embodiments, which is used to separate nitrogen and carbon dioxide. The separated carbon dioxide is a high-purity gas and is sent to a storage tank for storage. The nitrogen separated by the membrane separator 301 is sent to the desorption tower 210 again for circulation. In some embodiments, the membrane separator 301 is equipped with a self-pressurizing device to increase the pressure of the product gas. After passing through the membrane separation device, if the requirements of the liquefaction module on the ship are met, the traditional compression module can be cancelled, and the product gas that meets the pressure can be directly liquefied and stored.

In order to purify the product gas, the gas transfer unit 300 also includes a condenser 302, which is arranged between the membrane separator 301 and the third outlet 203. The condenser 302 is used to separate water vapor in the product gas, and the separated condensed water vapor is sent to the desorption tower 210 for circulation to supplement the water vapor evaporation loss in the desorption tower 210.

In some embodiments, the gas transfer unit 300 includes a second heater 303, the desorption unit 200 has a fourth inlet 204, and the second heater 303 is arranged between the membrane separator 301 and the fourth inlet 204, and is used to heat the desorption gas sent into the desorption tower 210 to maintain the temperature in the desorption tower 210. In some specific embodiments, the second heater 303 is an electric heater. In some specific embodiments, the temperature of the desorption gas heated by the second heater 303 is between 85 and 95°C, such as 90°C.

In some embodiments, the gas transfer unit 300 has a fifth inlet 304, which is used to feed desorption gas. In some specific embodiments, the fifth inlet 304 is located between the second heater 303 and the membrane separator 301. For example, nitrogen can be fed into the fifth inlet 304, which enters the second heater 303 together with the nitrogen sent from the membrane separator 301 for heating, and then is sent into the desorption tower 210 to supplement or adjust the amount of desorption gas sent into the desorption tower 210.

In some embodiments, the capture storage system of the present application further includes a circulation unit 400, which includes a first circulation pump 401, the inlet of the first circulation pump 401 is connected to the first outlet 102, and the second inlet 201 is connected. In some embodiments, the first circulation pump 401 is a rich liquid circulation pump.

The circulation unit 400 includes a second circulation pump 402, the absorption unit 100 has a third inlet 103, the desorption unit 200 has a second outlet 202, the inlet of the second circulation pump 402 is connected to the second outlet 202, and the outlet of the second circulation pump 402 is connected to the third inlet 103. In some embodiments, the second circulation pump 402 is a lean liquid circulation pump.

In order to adjust the temperature of the lean/rich liquid sent into the absorption tower 110 and the desorption tower 210, the circulation unit 400 includes a heat exchanger 403, which is connected to the outlet of the first circulation pump 401 and the outlet of the second circulation pump 402 respectively, and the heat exchanger 403 has a first heat exchange outlet 4031, and the first heat exchange outlet 4031 is connected to the second inlet 201; the heat exchanger 403 has a second heat exchange outlet 4032, and the second heat exchange outlet 4032 is connected to the third inlet 103.

In some embodiments, the temperature range of the first solution sent from the outlet of the first circulation pump 401 to the heat exchanger 403 is 30-40°C. After heat exchange in the heat exchanger 403, the temperature of the rich liquid sent from the first heat exchange outlet 4031 of the heat exchanger 403 is about 75-85°C, such as 80°C.

In some embodiments, the temperature range of the second solution sent from the outlet of the second circulation pump 402 to the heat exchanger 403 is 85-95°C, such as 90°C. After heat exchange in the heat exchanger 403, the temperature of the lean liquid sent from the second heat exchange outlet 4032 of the heat exchanger 403 is about 45-55°C, such as 50°C.

In some embodiments, the circulation unit 400 includes a first heater 404 disposed between the first heat exchange outlet 4031 and the second inlet 201. The first heater 404 is used to heat the first solution sent from the heat exchanger 403 to a desired temperature, such as from 80°C to 90°C.

In some embodiments, the circulation unit 400 includes a cooler 405, which is disposed between the second heat exchange outlet 4032 and the third inlet 103. The cooler 405 is used to reduce the temperature of the second solution entering the absorption tower 110, such as reducing the temperature of the second solution from 50°C to 40°C.

As shown in FIG3 , a gas capture method using the gas capture storage system shown in FIG2 includes:

The carbon-containing flue gas is sent to the absorption unit 100, which contains an absorption liquid. The carbon-containing flue gas includes carbon dioxide. After the absorption liquid contacts the carbon-containing flue gas, a first solution is formed; the first solution is sent to the desorption unit 200, and the gas transfer unit 300 sends desorption gas to the desorption unit 200 to desorb the carbon dioxide in the first solution; the first solution after desorption forms a second solution, and the second solution is sent from the desorption unit 200 to the absorption unit 100.

In some specific application examples, the high-temperature ship exhaust gas containing CO ₂ first flows through the absorption tower 110, where the ship exhaust gas and the absorption liquid are subjected to countercurrent convection mass transfer, and then the clean exhaust gas is discharged from the top of the absorption tower 110. The rich liquid is heated by the heat exchanger 403 under the action of the pump group and enters the desorption tower 210 from the top. In the desorption tower 210, the rich liquid enters the tower from the top, and the nitrogen enters the tower from the bottom after being heated by the first heater 404. The rich liquid is desorbed under the action of the hot nitrogen and CO ₂ is released again. The product gas (CO ₂ +N2 + a small amount of water vapor) at the top outlet of the desorption tower passes through the condenser 302 and the membrane separator 301, The purified high-purity CO ₂ gas will be discharged from the system for the next step of storage. The separated nitrogen gas will then enter the desorption tower 210 from the lower part of the desorption tower 210 through the membrane separator 301 and the first heater 404 to continue the next cycle.

In some specific embodiments, the absorption liquid is an organic amine solution. The present application uses an organic amine solution to chemically absorb and desorb CO ₂ in carbon-containing flue gas. The desorption gas is nitrogen. Nitrogen stripping is used for desorption to reduce the CO ₂ partial pressure in the desorption tower 210 environment and promote the desorption reaction. The positive reaction (absorption) of this process occurs at room temperature 30-40°C and normal pressure, and the reverse reaction (desorption) occurs at a lower temperature 80-90°C and normal pressure.

In a specific application example, the absorption tower 110 has a first gas pressure, and the pressure range of the first gas pressure is 0.8 to 1.2 bar, such as the first gas pressure is 1 bar. The optimal gas pressure of the absorption tower 110 of the present application is 1 bar, and the entire system does not need to apply any pressure, which reduces the pressure on components such as the circulation pump in the circulation unit 400. In addition, nitrogen gas is used to reduce the _CO2 gas partial pressure in the desorption tower 210, promote the _CO2 desorption reaction, reduce the system regeneration energy consumption, and cut the system operating cost. In a specific application example, the absorption tower 110 has a first temperature, and the first temperature ranges from 30 to 40°C.

In a specific application example, the desorption tower 210 has a second air pressure, and the pressure range of the second air pressure is 0.8 to 1.2 bar, such as 1 bar. The optimal air pressure of the desorption tower 210 of the present application is 1 bar, and the entire system does not need to apply any pressure, which reduces the pressure of components such as the circulation pump in the circulation unit 400 and the amount of the pump group, and reduces the construction difficulty. In a specific application example, the desorption tower 210 has a second temperature, and the second temperature range is 80 to 90°C.

The present application adopts nitrogen stripping to desorb CO ₂ , and there is no need to heat the absorption liquid to the desorption temperature of 110-120° C., which reduces the energy consumption demand on the ship side and ensures the functional integrity of the system.

In some specific embodiments, carbon dioxide is captured by:

The carbon-containing flue gas is sent to the absorption unit 100. The absorption unit 100 contains an absorption liquid. The carbon-containing flue gas contains carbon dioxide. After the absorption liquid contacts the carbon-containing flue gas, a first solution is formed. The absorption liquid in the absorption tower 110 is an organic amine solution. The temperature in the absorption tower is 40° C. and the air pressure in the absorption tower 110 is 1 bar.

After the first solution is heat exchanged in the heat exchanger 403, it is sent to the desorption unit 200. The temperature of the first solution after heat exchange in the heat exchanger 403 rises from 40°C to 80°C. When the temperature in the desorption tower 210 is maintained at 80°C, the first heater 404 does not need to be heated. When the temperature in the desorption tower 210 is maintained at 90°C, the rich solution is heated to 90°C by the first heater 404 and sent to the desorption tower 210.

The gas transfer unit 300 feeds desorption gas into the desorption unit 200. The desorption gas is nitrogen. The nitrogen is heated to 90° C. by the second heater 303 and fed to the desorption tower 210 from bottom to top for desorbing carbon dioxide in the first solution. The temperature of the desorption tower 210 is maintained at 80-90° C. and the pressure is 1 bar. In this embodiment, the temperature of the desorption tower 210 is maintained at 90° C.

The first solution after desorption forms a second solution. After the second solution passes through the heat exchanger 403 for heat exchange, the temperature of the second solution drops from 90°C to 50°C. Subsequently, the second solution is cooled to 40°C by a cooler arranged between the heat exchanger 403 and the third inlet 103 of the absorption tower 110 and is sent to the absorption tower 110.

The product gas sent out from the third outlet 203 of the desorption tower 210 is cooled to 30° C. by the condenser 302 and sent to the nitrogen membrane separator. The carbon dioxide separated by the nitrogen membrane separator is sent to the next process, and the separated nitrogen enters the cycle again.

Please refer to Table 1, which compares the energy consumption of carbon dioxide desorption in Table 1 with the energy consumption of the gas lift desorption method of the present application: the setting parameters of the absorption tower are the same, the difference between the carbon dioxide desorption and the present application is that no gas transfer unit is set, the temperature range of the desorption tower in the carbon dioxide desorption method is 110-120°C, and the pressure is 1.5bar, and the temperature range of the desorption tower of the present application is 80-90°C, and the pressure is 1bar.

Table 1 Comparison of energy consumption of different processes

Table 2 Energy consumption of gas stripping desorption in this application


Note 1: The energy consumption in Table 2 is calculated based on 150Nm ³ /h product gas; the sensible heat of 40 to 80 includes the total energy consumption of the first heater and the second heater;

It can be seen from the results of Table 1 and Table 2 that the present application captures carbon dioxide in carbon-containing flue gas by a gas stripping desorption method, which can greatly reduce the energy consumption of the system, reduce the temperature of the rich liquid sent into the desorption tower 210 by the circulation unit 400, and reduce the energy consumption of the entire system. In addition, the present application can not only separate carbon dioxide and desorption gas through a nitrogen membrane separator, but also the separated carbon dioxide can directly liquefy and store the product gas that meets the pressure without adding a separate pressurizing device. In addition, the present application reduces the desorption pressure of carbon dioxide by sending the desorption gas into the desorption tower 210.

In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

The above is a detailed introduction to a gas capture and storage system and method provided in the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for those skilled in the art, according to the idea of the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Reference numerals in the figure: 100-absorption unit, 110-absorption tower 101-first inlet, 102-first outlet, 103-third inlet, 200-desorption unit, 210-desorption tower, 201-second inlet, 202-second outlet, 203-third outlet, 204-fourth inlet, 300-gas transfer unit, 301-membrane separator, 302-condenser, 303-second heater, 304-fifth inlet, 400-circulation unit, 401-first circulation pump, 402-second circulation pump, 403-heat exchanger, 4031-first heat exchange outlet, 4032-second heat exchange outlet, 404-first heater, 405-cooler.

Claims (18)

A gas capture storage system, comprising: An absorption unit (100), the absorption unit (100) having a first inlet (101) and a first outlet (102), carbon-containing flue gas is fed into the absorption unit (100) from the first inlet (101), the carbon-containing flue gas contains carbon dioxide, the carbon-containing flue gas contacts with an absorption liquid in the absorption unit (100) to form a first solution, and the first solution is fed out from the first outlet (102); A desorption unit (200), wherein the desorption unit (200) has a second inlet (201), and the first solution delivered from the first outlet (102) is delivered to the desorption unit (200) from the second inlet (201); A gas transfer unit (300), wherein the gas transfer unit (300) is used to feed a desorption gas into the desorption unit (200), wherein the desorption gas contacts the first solution to complete the desorption of at least a portion of the carbon dioxide to form a second solution, and the second solution is fed from the desorption unit (200) into the absorption unit (100). The gas capture storage system according to claim 1, further comprising a circulation unit (400), wherein the circulation unit (400) comprises a first circulation pump (401), wherein the inlet of the first circulation pump (401) is connected to the first outlet (102), and the outlet of the first circulation pump (401) is connected to the second inlet (201). The gas capture storage system according to claim 2, wherein the circulation unit (400) comprises a second circulation pump (402), the absorption unit (100) has a third inlet (103), the desorption unit (200) has a second outlet (202), the inlet of the second circulation pump (402) is connected to the second outlet (202), and the outlet of the second circulation pump (402) is connected to the third inlet (103). The gas capture storage system according to claim 3, wherein the circulation unit (400) comprises a heat exchanger (403), and the heat exchanger (403) is respectively connected to the outlet of the first circulation pump (401) and the outlet of the second circulation pump (402). The gas capture storage system according to claim 4, wherein the heat exchanger (403) has a first heat exchange outlet (4031), and the first heat exchange outlet (4031) is connected to the second inlet (201); the heat exchanger (403) has a second heat exchange outlet (4032), and the second heat exchange outlet (4032) is connected to the third inlet (103). The gas capture storage system according to claim 5, wherein the circulation unit (400) It comprises a first heater (404), wherein the first heater (404) is arranged between the first heat exchange outlet (4031) and the second inlet (201). The gas capture storage system according to claim 5 or 6, wherein the circulation unit (400) comprises a cooler (405), and the cooler (405) is arranged between the second heat exchange outlet (4032) and the third inlet (103). The gas capture storage system according to any one of claims 5 to 7, wherein the gas transfer unit (300) comprises a membrane separator (301), the desorption unit (200) has a third outlet (203), and the inlet of the membrane separator (301) is connected to the third outlet (203). The gas capture storage system according to claim 8, wherein the gas transfer unit (300) comprises a condenser (302), and the condenser (302) is arranged between the membrane separator (301) and the third outlet (203). The gas capture storage system according to claim 8 or 9, wherein the gas transfer unit (300) comprises a second heater (303), the desorption unit (200) has a fourth inlet (204), and the second heater (303) is arranged between the membrane separator (301) and the fourth inlet (204). The gas capture storage system according to any one of claims 8 to 10, wherein the gas transfer unit (300) has a fifth inlet (304), and the fifth inlet (304) is used to feed the desorption gas. A gas capture method comprising: The carbon-containing flue gas is fed into an absorption unit (100), wherein the absorption unit (100) contains an absorption liquid, the carbon-containing flue gas contains carbon dioxide, and the absorption liquid forms a first solution after contacting the carbon-containing flue gas; The first solution is fed into a desorption unit (200), and a gas transmission unit (300) feeds a desorption gas into the desorption unit (200) for desorbing carbon dioxide in the first solution; The first solution after desorption forms a second solution, and the second solution is sent from the desorption unit (200) to the absorption unit (100). The gas capture method according to claim 12, wherein the absorption unit (100) has a first gas pressure, and the pressure range of the first gas pressure is 0.8 to 1.2 bar. The gas capture method according to claim 12, wherein the absorption unit (100) has There is a first temperature, and the first temperature ranges from 30 to 40°C. The gas capture method according to claim 12, wherein the absorption unit (100) has a first gas pressure, the pressure range of the first gas pressure is 0.8 to 1.2 bar, and the absorption unit (100) has a first temperature, the first temperature range is 30 to 40°C. The gas capture method according to any one of claims 12 to 15, wherein the desorption unit (200) has a second gas pressure, and the pressure range of the second gas pressure is 0.8 to 1.2 bar. The gas capture method according to any one of claims 12 to 15, wherein the desorption unit (200) has a second temperature, and the second temperature ranges from 80 to 90°C. The gas capture method according to any one of claims 12 to 15, wherein the desorption unit (200) has a second gas pressure, the pressure range of the second gas pressure is 0.8 to 1.2 bar, and the desorption unit (200) has a second temperature, the second temperature range is 80 to 90°C.