Carbon dioxide capture, energy storage and power generation coupling system

Abstract

The utility model relates to the technical field of new energy, and provides a carbon dioxide capture, energy storage and power generation coupling system which comprises a carbon dioxide capture unit, a carbon dioxide energy storage unit, a first control valve, a power generation unit and a second control valve. The carbon dioxide energy storage unit is connected with the carbon dioxide capturing unit through a first control valve, the carbon dioxide energy storage unit is connected with the power generation unit, and the power generation unit is connected with the carbon dioxide capturing unit through a second control valve. Through the arrangement of the system structure, the carbon dioxide capturing unit, the carbon dioxide energy storage unit and the power generation unit are arranged in a coupled mode, and finished liquid carbon dioxide produced by the carbon dioxide capturing unit can be conveyed into the carbon dioxide energy storage unit by controlling the working states of the first control valve and the second control valve; the carbon dioxide energy storage unit can supply energy to the power generation unit, and carbon dioxide generated after power generation of the power generation unit can also be returned and collected to the carbon dioxide capture unit. Therefore, the energy efficiency and the economic performance of the whole system are greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of new energy, and in particular to a carbon dioxide capture, energy storage and power generation coupling system. Background Art

[0002] Carbon capture systems are usually installed in industrial plants such as thermal power plants, cement plants, and coal kilns. Conventional carbon capture systems are independent systems. Independent carbon capture systems require a large overall investment, and the sales revenue of the liquid carbon dioxide produced is low, and the energy efficiency is low and the economic efficiency is poor. Utility Model Content

[0003] The utility model provides a carbon dioxide capture, energy storage and power generation coupling system to solve the above technical problems.

[0004] According to the utility model, a carbon dioxide capture, energy storage and power generation coupling system is provided, comprising a carbon dioxide capture unit, a carbon dioxide energy storage unit, a first control valve, a power generation unit and a second control valve.

[0005] The carbon dioxide energy storage unit is connected to the carbon dioxide capture unit through the first control valve. The carbon dioxide energy storage unit is connected to the power generation unit. The power generation unit is connected to the carbon dioxide capture unit through the second control valve.

[0006] According to a carbon dioxide capture, energy storage and power generation coupling system provided by the utility model, the carbon dioxide capture unit includes a precooler, a first liquefaction booster compressor, a desulfurization tower, a drying adsorption tower, a distillation tower, a first refrigeration unit liquefier and a finished liquid carbon dioxide storage tank.

[0007] The precooler is connected to the first liquefaction booster compressor, which is connected to the desulfurization tower. The desulfurization tower is connected to the drying adsorption tower, which is connected to the distillation tower. The distillation tower is connected to the first refrigeration unit liquefier. The first refrigeration unit liquefier is connected to the finished liquid carbon dioxide storage tank.

[0008] According to a carbon dioxide capture, energy storage and power generation coupling system provided by the utility model, the carbon dioxide capture unit also includes a buffer tank. The inlet of the buffer tank is used to input the crude carbon dioxide gas after carbon capture absorption and regeneration. The outlet of the buffer tank is connected to the precooler.

[0009] According to a carbon dioxide capture, energy storage and power generation coupling system provided by the utility model, the carbon dioxide energy storage unit comprises a carbon dioxide energy storage tank, which is connected to the finished liquid carbon dioxide storage tank via the first control valve.

[0010] According to a carbon dioxide capture, energy storage and power generation coupling system provided by the utility model, a liquid booster pump is provided between the carbon dioxide energy storage tank and the first control valve.

[0011] According to a carbon dioxide capture, energy storage and power generation coupling system provided by the utility model, the power generation unit includes an evaporator, a primary heater and a primary expander.

[0012] Wherein, the carbon dioxide energy storage tank is connected to the evaporator, the evaporator is connected to the primary heater, and the primary heater is connected to the primary expander.

[0013] According to a carbon dioxide capture, energy storage and power generation coupling system provided by the utility model, the power generation unit also includes a secondary heater and a secondary expander.

[0014] Wherein, the first-stage expander is connected to the second-stage heater. The second-stage heater is connected to the second-stage expander.

[0015] According to a carbon dioxide capture, energy storage and power generation coupling system provided by the utility model, the heat exchange medium inlet of the first-stage heater and the heat exchange medium inlet of the second-stage heater are both connected to the supply end of the high-temperature steam heat source of the thermal power plant. The heat exchange medium outlet of the first-stage heater and the heat exchange medium outlet of the second-stage heater are both connected to the return air end of the high-temperature steam heat source of the thermal power plant.

[0016] According to a carbon dioxide capture, energy storage and power generation coupling system provided by the utility model, the carbon dioxide capture, energy storage and power generation coupling system also includes a radiator, a second liquefaction booster compressor and a second refrigeration unit liquefier.

[0017] The secondary expander is connected to the radiator. The radiator is connected to the second liquefaction booster compressor. The second liquefaction booster compressor is connected to the second refrigeration unit liquefier. The second refrigeration unit liquefier is connected to the finished liquid carbon dioxide storage tank through the second control valve.

[0018] According to a carbon dioxide capture, energy storage and power generation coupling system provided by the utility model, the first liquefaction booster compressor and the second liquefaction booster compressor both include a scroll compressor, a piston compressor, a screw compressor or a centrifugal compressor.

[0019] The carbon dioxide capture, energy storage and power generation coupling system provided by the utility model includes a carbon dioxide capture unit, a carbon dioxide energy storage unit, a first control valve, a power generation unit and a second control valve. Among them, the carbon dioxide energy storage unit is connected to the carbon dioxide capture unit, and a first control valve is arranged between the two. The carbon dioxide energy storage unit is connected to the power generation unit, and the power generation unit is connected to the carbon dioxide capture unit, and a second control valve is arranged between the two. During operation, the carbon dioxide capture unit can produce finished liquid carbon dioxide. By controlling the working state of the first control valve, the finished liquid carbon dioxide produced by the carbon dioxide capture unit can be transported to the carbon dioxide energy storage unit for storage, and the carbon dioxide energy storage unit can supply energy to the power generation unit. By controlling the working state of the second control valve, the carbon dioxide generated by the power generation unit after power generation can be returned and collected in the carbon dioxide capture unit.

[0020] Through this system structure setting, the carbon dioxide capture unit, the carbon dioxide energy storage unit and the power generation unit are coupled, and by controlling the working states of the first control valve and the second control valve, the finished liquid carbon dioxide produced by the carbon dioxide capture unit can be transported to the carbon dioxide energy storage unit, and the carbon dioxide energy storage unit can supply energy to the power generation unit. The carbon dioxide generated by the power generation unit after power generation can also be returned to the carbon dioxide capture unit for collection. As a result, the energy efficiency and economic performance of the entire system are greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 It is a schematic diagram of the system structure of the carbon dioxide capture, energy storage and power generation coupling system provided by the utility model;

[0023] Reference numerals:

[0024] 110. First control valve; 120. Second control valve; 210. Precooler; 220. First liquefaction booster compressor; 230. Desulfurization tower; 240. Drying adsorption tower; 250. Distillation tower; 260. First refrigeration unit liquefier; 270. Finished liquid carbon dioxide storage tank; 280. Buffer tank; 310. Carbon dioxide energy storage tank; 320. Liquid booster pump; 410. Evaporator; 420. Primary heater; 430. Primary expander; 440. Secondary heater; 450. Secondary expander; 510. Radiator; 520. Second liquefaction booster compressor; 530. Second refrigeration unit liquefier. DETAILED DESCRIPTION

[0025] The following is a further detailed description of the implementation of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0026] In the description of the embodiments of the present utility model, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present utility model. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0027] In the description of the embodiments of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to specific circumstances.

[0028] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0029] In the description of this specification, the description of reference terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model embodiment. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, in the absence of contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples to make the purpose, technical solutions and advantages of the utility model embodiment clearer. The technical solutions in the utility model embodiment will be clearly and completely described below in conjunction with the drawings in the utility model embodiment. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in the field without creative work belong to the scope of protection of the utility model.

[0030] Combine the following Figure 1 A carbon dioxide capture, energy storage and power generation coupling system provided in an embodiment of the utility model is described. It should be understood that the following description is only an illustrative embodiment of the utility model and does not constitute any particular limitation to the utility model.

[0031] The embodiment of the utility model provides a carbon dioxide capture, energy storage and power generation coupling system, such as Figure 1 As shown, the carbon dioxide capture, energy storage and power generation coupling system includes a carbon dioxide capture unit, a carbon dioxide energy storage unit, a first control valve 110 , a power generation unit and a second control valve 120 .

[0032] The carbon dioxide energy storage unit is connected to the carbon dioxide capture unit through a first control valve 110 , the carbon dioxide energy storage unit is connected to the power generation unit, and the power generation unit is connected to the carbon dioxide capture unit through a second control valve 120 .

[0033] The carbon dioxide capture, energy storage and power generation coupling system provided by the utility model includes a carbon dioxide capture unit, a carbon dioxide energy storage unit, a first control valve 110, a power generation unit and a second control valve 120. Among them, the carbon dioxide energy storage unit is connected to the carbon dioxide capture unit, and a first control valve 110 is arranged between the two. The carbon dioxide energy storage unit is connected to the power generation unit, and the power generation unit is connected to the carbon dioxide capture unit, and a second control valve 120 is arranged between the two. During operation, the carbon dioxide capture unit can produce finished liquid carbon dioxide. By controlling the working state of the first control valve 110, the finished liquid carbon dioxide produced by the carbon dioxide capture unit can be transported to the carbon dioxide energy storage unit for storage, and the carbon dioxide energy storage unit can supply energy to the power generation unit. By controlling the working state of the second control valve 120, the carbon dioxide generated by the power generation unit after power generation can be returned and collected in the carbon dioxide capture unit.

[0034] Through this system structure setting, the carbon dioxide capture unit, the carbon dioxide energy storage unit and the power generation unit are coupled, and by controlling the working states of the first control valve 110 and the second control valve 120, the finished liquid carbon dioxide produced by the carbon dioxide capture unit can be transported to the carbon dioxide energy storage unit, the carbon dioxide energy storage unit can supply energy to the power generation unit, and the carbon dioxide generated by the power generation unit after power generation can also be returned to the carbon dioxide capture unit for collection. As a result, the energy efficiency and economic performance of the entire system are greatly improved.

[0035] In one embodiment of the present invention, the carbon dioxide capture unit includes a precooler 210, a first liquefaction booster compressor 220, a desulfurization tower 230, a drying adsorption tower 240, a distillation tower 250, a first refrigeration unit liquefier 260 and a finished liquid carbon dioxide storage tank 270.

[0036] Among them, the precooler 210 is connected to the first liquefaction booster compressor 220, the first liquefaction booster compressor 220 is connected to the desulfurization tower 230, the desulfurization tower 230 is connected to the drying adsorption tower 240, the drying adsorption tower 240 is connected to the distillation tower 250, the distillation tower 250 is connected to the first refrigeration unit liquefier 260, and the first refrigeration unit liquefier 260 is connected to the finished liquid carbon dioxide storage tank 270.

[0037] Furthermore, in one embodiment of the present invention, the carbon dioxide capture unit further comprises a buffer tank 280 . The inlet of the buffer tank 280 is used to input the raw carbon dioxide gas after carbon capture absorption and regeneration. The outlet of the buffer tank 280 is connected to the precooler 210 .

[0038] Specifically, the buffer tank 280 is used to receive the crude carbon dioxide after adsorption and regeneration at the front end of the carbon capture process. The crude carbon dioxide in the buffer tank 280 is mainly composed of a mixture of carbon dioxide, water vapor, sulfur dioxide, etc., with a temperature of 30-40°C, and the carbon dioxide component accounts for 90%-95%. The precooler 210 is used to adjust the temperature of the gas entering the first liquefied compressor at any time. The temperature of the gas after precooling by the precooler 210 is usually 25-35°C.

[0039] During the carbon capture process, the gas after precooling by the precooler 210 first enters the first liquefied compressor for compression and supercharging. Under normal circumstances, the first liquefied compressor can compress the crude carbon dioxide gas to about 2.5MPa. The compressed and supercharged crude carbon dioxide gas enters the desulfurization tower 230 and the drying adsorption tower 240 in turn. The desulfurization tower 230 is used to remove sulfides in carbon dioxide, such as hydrogen sulfide and mercaptan. The drying adsorption tower 240 is used to remove moisture from carbon dioxide to prevent water vapor from condensing into liquid water at low temperatures, causing corrosion and blockage to equipment and pipelines. The carbon dioxide after desulfurization and dry adsorption enters the distillation tower 250 for further purification to remove other impurities and impurities, such as oxygen, nitrogen, argon, etc. Among them, the distillation tower 250 is a new type of composite packing tower, cylindrical. A condenser is set at the top of the distillation tower 250, two sections of stainless steel wire mesh structured packing are set in the middle section of the tower, and the lower part is a liquid storage area. At the same time, a reboiler is set at the bottom of the tower. The reboiler heat source can come from high-temperature heat sources in industrial plants such as thermal power plant steam. A tower top heat exchange separator is set on the top of the tower, which is used to cool the carbon dioxide steam coming out of the tower top and further remove a small amount of impurities in the carbon dioxide gas. The purified carbon dioxide enters the first refrigeration unit liquefier 260 to cool to -20°C for liquefaction. Finally, the finished liquid carbon dioxide enters the finished liquid carbon dioxide storage tank 270.

[0040] In one embodiment of the present invention, Figure 1 As shown, the carbon dioxide energy storage unit includes a carbon dioxide energy storage tank 310. The carbon dioxide energy storage tank 310 is connected to the finished liquid carbon dioxide storage tank 270 through a first control valve 110.

[0041] In another embodiment of the present invention, Figure 1 As shown, a liquid booster pump 320 is provided between the carbon dioxide energy storage tank 310 and the first control valve 110 .

[0042] For example, during the carbon dioxide energy storage process, the liquid booster pump 320 can pressurize the finished liquid carbon dioxide in the finished liquid carbon dioxide storage tank 270 from 2.5MPa to 7MPa, so that the finished liquid carbon dioxide meets the pressure requirements during energy release and discharge. Subsequently, the high-pressure liquid carbon dioxide can be stored in the carbon dioxide energy storage tank 310, which can also adjust the pressure fluctuations in the system to balance the supply and demand of carbon dioxide.

[0043] In one embodiment of the present invention, the power generation unit includes an evaporator 410 , a primary heater 420 , and a primary expander 430 .

[0044] The carbon dioxide energy storage tank 310 is connected to the evaporator 410 , the evaporator 410 is connected to the primary heater 420 , and the primary heater 420 is connected to the primary expander 430 .

[0045] In one embodiment of the present invention, the power generation unit further includes a secondary heater 440 and a secondary expander 450 .

[0046] The first-stage expander 430 is connected to the second-stage heater 440 , and the second-stage heater 440 is connected to the second-stage expander 450 .

[0047] During the power generation process, the high-pressure liquid carbon dioxide in the carbon dioxide energy storage tank 310 enters the evaporator 410 to gasify the liquid carbon dioxide. The gasified carbon dioxide enters the primary heater 420, the primary expander 430, the secondary heater 440 and the secondary expander 450 in sequence. Among them, the primary expander 430 and the secondary expander 450 are connected to the generator for power output. When releasing energy, the reheated gaseous carbon dioxide enters the primary expander 430 and the secondary expander 450 to drive the impellers of the primary expander 430 and the secondary expander 450 to do work.

[0048] In one embodiment of the utility model, the heat exchange medium inlet of the first heater 420 and the heat exchange medium inlet of the second heater 440 are both connected to the supply end of the high-temperature steam heat source of the thermal power plant. The heat exchange medium outlet of the first heater 420 and the heat exchange medium outlet of the second heater 440 are both connected to the return air end of the high-temperature steam heat source of the thermal power plant. The heat source of this part utilizes the high-temperature steam heat source such as the thermal power plant to realize the graded utilization of heat.

[0049] In one embodiment of the present invention, the carbon dioxide capture, energy storage and power generation coupling system further includes a radiator 510 , a second liquefaction booster compressor 520 and a second refrigeration unit liquefier 530 .

[0050] Among them, the secondary expansion machine 450 is connected to the radiator 510, the radiator 510 is connected to the second liquefaction booster compressor 520, the second liquefaction booster compressor 520 is connected to the second refrigeration unit liquefier 530, and the second refrigeration unit liquefier 530 is connected to the finished liquid carbon dioxide storage tank 270 through the second control valve 120.

[0051] During the working process, the purity of carbon dioxide in the gas passing through the carbon dioxide energy storage unit and the power generation unit is further improved. This part of carbon dioxide first enters the radiator 510, which is used to regulate the temperature of the gas entering the second liquefied booster compressor 520 through the secondary expander 450, so that the gas temperature is stabilized at 25-35°C. Then it enters the second liquefied booster compressor 520 to compress the atmospheric pressure carbon dioxide gas at the expansion outlet to 2.5MPa. Then it enters the second refrigeration unit liquefier 530 to cool the carbon dioxide to -20°C for liquefaction, and finally enters the finished liquid carbon dioxide storage tank 270 through the second control valve 120.

[0052] It should be noted here that the present invention does not impose any limitation on the specific types of the first liquefaction booster compressor 220 and the second liquefaction booster compressor 520. For example, the first liquefaction booster compressor 220 and the second liquefaction booster compressor 520 may both include a scroll compressor, a piston compressor, a screw compressor, or a centrifugal compressor.

[0053] Generally speaking, during the carbon dioxide capture process, the crude carbon dioxide gas (0.1-0.2MPa, 40-50°C) generated by the regeneration device at the front end of the carbon capture process enters the precooler 210 and is cooled to a suitable compressor inlet temperature (25-35°C); it is then compressed to about 2.5MPa by the first liquefaction booster compressor 220; it then enters the desulfurization tower 230 and the drying adsorption tower 240 in turn to remove sulfur-containing gases, organic matter and other impurity gases, and is deeply dehumidified by molecular sieves; it then enters the distillation tower 250 for distillation purification and gas-liquid separation; it flows out from the top of the tower after the heat exchange and cooling action of the heat exchange separator at the top of the tower; it then enters the first refrigeration unit liquefier 260 to be cooled again to about -20°C to achieve a certain supercooling state, and after meeting the requirements for the finished product of liquefied carbon dioxide, it is filled into the finished liquid carbon dioxide storage tank 270 for subsequent storage, utilization and loading and transportation.

[0054] In the process of carbon dioxide energy storage and power generation, when the external energy storage system is needed for peak and valley regulation, the first control valve 110 and the second control valve 120 are opened. The liquid carbon dioxide (2.5MPa, -20°C) stored in the finished liquid carbon dioxide storage tank 270 is pressurized to 7MPa by the liquid booster pump 320 and then enters the carbon dioxide energy storage tank 310 for temporary storage to balance the pressure before and after. Then it is heated and gasified by the high-temperature steam heat source such as the thermal power plant in the evaporator 410, and then the gaseous carbon dioxide is further heated to the intake temperature of the first expander 430 and the second expander 450 in the first heater 420 and the second heater 440 in turn. The heat of this process also comes from the high-temperature steam heat source such as the thermal power plant. The high-temperature carbon dioxide enters the first expander 430 and the second expander 450 in turn to expand and work, driving the generator to output electrical energy. Then, the carbon dioxide expanded and worked in the secondary expansion machine 450 is cooled to a suitable compressor inlet temperature (25-35°C) in the radiator 510, and then enters the second liquefaction booster compressor 520 to be compressed to about 2.5MPa. It is cooled again to about -20°C through the second refrigeration unit liquefier 530 to reach a certain supercooling state, meeting the requirements for liquefied CO2 productization, and finally refilled into the finished liquid carbon dioxide storage tank 270 for storage, utilization and loading and transportation.

[0055] According to the embodiments described above, the carbon dioxide capture, energy storage and power generation coupling system can not only improve the energy utilization efficiency, but also combine carbon dioxide capture, storage and power generation. In the energy release power generation stage, the high-pressure liquid carbon dioxide generated in the carbon dioxide capture and storage stages can be used as the working medium, reducing the installation of additional energy storage equipment. At the same time, the supercooled water of the system refrigeration unit can be used during liquefaction, and the high-temperature steam heat source such as the thermal power plant can be used during power generation, thereby improving the energy utilization efficiency of the entire system. It can also achieve cost reduction and efficiency improvement. By coupling the carbon dioxide capture and energy storage systems, infrastructure and operating resources can be shared, thereby reducing the investment and operating costs required for the separate deployment of each system, thereby reducing the unit energy cost and achieving scaled cost-effectiveness. The coupling system can save the related costs and floor space of additional equipment deployment in the carbon dioxide energy storage stage, and add additional energy storage benefits to the carbon dioxide capture industry, enhancing the economic feasibility of the industrial model. At the same time, it can also enhance system flexibility. The coupled system provides more operational flexibility. It can capture and store carbon dioxide when electricity demand is low, and release the captured carbon dioxide for power generation or other purposes when electricity demand is peak, and perform peak-valley regulation, load balancing, phase adjustment and other power auxiliary services. In addition, it can provide new strategies for industrial carbon reduction, new ways to utilize greenhouse gas carbon dioxide, and new scenarios for the promotion of carbon dioxide capture and energy storage technology. It also provides new ideas for reducing carbon and increasing efficiency in high-energy-consuming industries such as thermal power and improving the overall efficiency of energy utilization.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A carbon dioxide capture, energy storage and power generation coupling system, characterized in that: It comprises a carbon dioxide capture unit, a carbon dioxide energy storage unit, a first control valve (110), a power generation unit and a second control valve (120), The carbon dioxide energy storage unit is connected to the carbon dioxide capture unit via the first control valve (110), the carbon dioxide energy storage unit is connected to the power generation unit, and the power generation unit is connected to the carbon dioxide capture unit via the second control valve (120).

2. The carbon dioxide capture, energy storage and power generation coupling system according to claim 1, characterized in that: The carbon dioxide capture unit comprises a precooler (210), a first liquefaction booster compressor (220), a desulfurization tower (230), a drying adsorption tower (240), a rectification tower (250), a first refrigeration unit liquefier (260) and a finished liquid carbon dioxide storage tank (270). The precooler (210) is connected to the first liquefaction booster compressor (220), the first liquefaction booster compressor (220) is connected to the desulfurization tower (230), the desulfurization tower (230) is connected to the drying adsorption tower (240), the drying adsorption tower (240) is connected to the distillation tower (250), the distillation tower (250) is connected to the first refrigeration unit liquefier (260), and the first refrigeration unit liquefier (260) is connected to the finished liquid carbon dioxide storage tank (270).

3. The carbon dioxide capture, energy storage and power generation coupling system according to claim 2, characterized in that: The carbon dioxide capture unit further comprises a buffer tank (280), the inlet of the buffer tank (280) is used to input the raw carbon dioxide gas after carbon capture absorption and regeneration, and the outlet of the buffer tank (280) is connected to the precooler (210).

4. The carbon dioxide capture, energy storage and power generation coupling system according to claim 3, characterized in that: The carbon dioxide energy storage unit comprises a carbon dioxide energy storage tank (310), and the carbon dioxide energy storage tank (310) is connected to the finished liquid carbon dioxide storage tank (270) via the first control valve (110).

5. The carbon dioxide capture, energy storage and power generation coupling system according to claim 4, characterized in that: A liquid booster pump (320) is provided between the carbon dioxide energy storage tank (310) and the first control valve (110).

6. The carbon dioxide capture, energy storage and power generation coupling system according to claim 5, characterized in that: The power generation unit includes an evaporator (410), a primary heater (420) and a primary expander (430). The carbon dioxide energy storage tank (310) is connected to the evaporator (410), the evaporator (410) is connected to the primary heater (420), and the primary heater (420) is connected to the primary expander (430).

7. The carbon dioxide capture, energy storage and power generation coupling system according to claim 6, characterized in that: The power generation unit further includes a secondary heater (440) and a secondary expander (450). Wherein, the first-stage expander (430) is connected to the second-stage heater (440), and the second-stage heater (440) is connected to the second-stage expander (450).

8. The carbon dioxide capture, energy storage and power generation coupling system according to claim 7, characterized in that: The heat exchange medium inlet of the first heater (420) and the heat exchange medium inlet of the second heater (440) are both connected to the supply end of the high-temperature steam heat source of the thermal power plant, and the heat exchange medium outlet of the first heater (420) and the heat exchange medium outlet of the second heater (440) are both connected to the return air end of the high-temperature steam heat source of the thermal power plant.

9. The carbon dioxide capture, energy storage and power generation coupling system according to claim 8, characterized in that: The carbon dioxide capture, energy storage and power generation coupling system further includes a radiator (510), a second liquefaction booster compressor (520) and a second refrigeration unit liquefier (530). The secondary expansion machine (450) is connected to the radiator (510), the radiator (510) is connected to the second liquefaction booster compressor (520), the second liquefaction booster compressor (520) is connected to the second refrigeration unit liquefier (530), and the second refrigeration unit liquefier (530) is connected to the finished liquid carbon dioxide storage tank (270) via the second control valve (120).

10. The carbon dioxide capture, energy storage and power generation coupling system according to claim 9, characterized in that: The first liquefaction booster compressor (220) and the second liquefaction booster compressor (520) both include scroll compressors, piston compressors, screw compressors, or centrifugal compressors.

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