Transcritical carbon dioxide energy storage system based on carbon dioxide capture and utilization

Abstract

The invention belongs to the technical field of carbon dioxide energy storage, and particularly relates to a transcritical carbon dioxide energy storage system based on carbon dioxide capture and utilization, which comprises a carbon dioxide capture system and a transcritical carbon dioxide energy storage system, the transcritical carbon dioxide energy storage system stores carbon dioxide captured by the carbon dioxide capturing system in the exhausted oil and gas reservoir, and cold / heat generated in the energy storage and release stage of the system is recycled through a waste heat utilization unit. The problems that in the prior art, a transcritical carbon dioxide energy storage system is high in carbon dioxide storage cost, large in volatility, low in system stability and low in efficiency are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of carbon dioxide energy storage, and in particular relates to a transcritical carbon dioxide energy storage system based on carbon dioxide capture and utilization. Background Art

[0002] Transcritical carbon dioxide energy storage technology is a large-scale energy storage technology that uses carbon dioxide as a circulating medium for energy storage and power generation. It is an important technical means to solve problems such as volatility and intermittency in renewable energy power generation.

[0003] In the prior art, a transcritical carbon dioxide energy storage system is usually configured as a closed-loop system, which requires two large-capacity gas storage reservoirs to store and utilize carbon dioxide. The gas storage cost is high, and as carbon dioxide is released from depleted oil and gas reservoirs, the gas storage pressure gradually decreases, which affects the stability of the system. At the same time, the existing transcritical carbon dioxide energy storage system has low efficiency. Summary of the invention

[0004] The purpose of the present invention is to provide a transcritical carbon dioxide energy storage system based on carbon dioxide capture and utilization to solve the above problems.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] A transcritical carbon dioxide energy storage system based on carbon dioxide capture and utilization, comprising:

[0007] CO2 capture system for capturing CO2;

[0008] A high-pressure gas chamber in a depleted oil and gas reservoir, used for storing high-pressure carbon dioxide, wherein the high-pressure gas chamber in the depleted oil and gas reservoir is connected to the carbon dioxide capture system via an energy replenishment compressor;

[0009] A low-pressure gas chamber in a depleted oil and gas reservoir, used for storing low-pressure carbon dioxide, wherein the low-pressure gas chamber in the depleted oil and gas reservoir is connected to the carbon dioxide capture system;

[0010] An energy release unit, used to release the energy in the carbon dioxide, wherein the air inlet of the energy release unit is connected to the high-pressure air chamber of the depleted oil and gas reservoir, and the air outlet of the energy release unit is connected to the low-pressure air chamber of the depleted oil and gas reservoir;

[0011] An energy storage unit, used to store energy in carbon dioxide, wherein an air inlet of the energy storage unit is connected to a low-pressure air chamber of the depleted oil and gas reservoir, and an air outlet of the energy storage unit is connected to a high-pressure air chamber of the depleted oil and gas reservoir;

[0012] An interstage cooling unit, arranged in the energy storage unit;

[0013] An interstage reheat unit, arranged in the energy release unit;

[0014] A waste heat utilization unit is used to utilize the cold / heat generated by the interstage cooling unit, the interstage reheat unit and the carbon dioxide capture system.

[0015] Preferably, the high-pressure gas chamber of the depleted oil and gas reservoir is connected to:

[0016] A high-pressure injection well, used for injecting high-pressure carbon dioxide into the high-pressure gas chamber of the depleted oil and gas reservoir, wherein the high-pressure injection well is connected to the energy replenishment compressor and the energy storage unit;

[0017] The high-pressure recovery well is used to release the high-pressure carbon dioxide in the high-pressure gas chamber of the depleted oil and gas reservoir, and the high-pressure recovery well is connected to the energy release unit.

[0018] Preferably, the low-pressure gas chamber of the depleted oil and gas reservoir is connected to:

[0019] A low-pressure injection well, used for injecting low-pressure carbon dioxide into the low-pressure gas chamber of the depleted oil and gas reservoir, wherein the low-pressure injection well is connected to the carbon dioxide capture system and the energy release unit;

[0020] A low-pressure recovery well is used to release the low-pressure carbon dioxide in the low-pressure gas chamber of the depleted oil and gas reservoir, and the low-pressure recovery well is connected to the energy storage unit.

[0021] Preferably, the energy release unit comprises:

[0022] A high-pressure expander, a medium-pressure expander, and a low-pressure expander are sequentially connected, the high-pressure expander is connected to the high-pressure recovery well, the low-pressure expander is connected to the low-pressure injection well, high-pressure carbon dioxide sequentially passes through the high-pressure expander, the medium-pressure expander, and the low-pressure expander to perform work and generate electricity, and the expanded low-pressure carbon dioxide passes through the low-pressure injection well into the low-pressure gas chamber of the depleted oil and gas reservoir for storage, the interstage reheat unit is arranged between the high-pressure expander, the medium-pressure expander, and the low-pressure expander, the interstage reheat unit heats the expanded carbon dioxide through the waste heat utilization unit, and at the same time stores the cold energy generated during the expansion of carbon dioxide in the waste heat utilization unit.

[0023] Preferably, the energy storage unit comprises:

[0024] A low-pressure compressor, a medium-pressure compressor, and a high-pressure compressor are sequentially connected, the low-pressure compressor is connected to the low-pressure recovery well, and the high-pressure compressor is connected to the high-pressure injection well. Low-pressure carbon dioxide is compressed and stored in sequence by the low-pressure compressor, the medium-pressure compressor, and the high-pressure compressor, and then injected into the high-pressure gas chamber of the depleted oil and gas reservoir through the high-pressure injection well for storage. The interstage cooling unit is arranged between the low-pressure compressor, the medium-pressure compressor, and the high-pressure compressor. The interstage cooling unit cools the compressed carbon dioxide gas through the waste heat utilization unit, and at the same time stores the heat generated during the compression of carbon dioxide in the waste heat utilization unit.

[0025] Preferably, the interstage reheat unit comprises:

[0026] a first interstage reheater, disposed between the high-pressure expander and the medium-pressure expander;

[0027] a second interstage reheater, disposed between the intermediate pressure expander and the low pressure expander;

[0028] The first inter-stage reheater and the second inter-stage reheater are both connected to the waste heat utilization unit for heat exchange.

[0029] Preferably, the interstage cooling unit comprises:

[0030] A first interstage cooler is arranged between the low-pressure compressor and the medium-pressure compressor;

[0031] A second interstage cooler is arranged between the intermediate pressure compressor and the high pressure compressor;

[0032] The first interstage cooler and the second interstage cooler are both connected to the waste heat utilization unit for heat exchange.

[0033] Preferably, the waste heat utilization unit comprises:

[0034] A cold storage tank, wherein the cold storage end is connected to the first interstage reheater, the second interstage reheater and the hot user by heat exchange, and the cold discharge end is connected to the first interstage cooler, the second interstage cooler and the cold user by heat exchange;

[0035] A heat storage tank, wherein a heat storage end is connected to the first interstage cooler, the second interstage cooler and the cold user for heat exchange, and a heat release end is connected to the first interstage reheater, the second interstage reheater and the hot user for heat exchange.

[0036] Preferably, the carbon dioxide capture system comprises:

[0037] Carbon dioxide absorption tower;

[0038] An alcoholamine solution storage tank is connected to the top liquid inlet of the carbon dioxide absorption tower, and the alcoholamine solution storage tank sends the alcoholamine lean liquid into the carbon dioxide absorption tower to absorb carbon dioxide;

[0039] A desorption tower, wherein the top inlet is connected to the bottom liquid outlet of the carbon dioxide absorption tower, and the top outlet of the desorption tower is connected to the energy replenishment compressor and the low-pressure injection well;

[0040] A reboiler, connected to the bottom outlet and the bottom inlet of the desorption tower;

[0041] A lean-rich liquid heat exchanger, wherein the cold source side inlet is connected to the carbon dioxide absorption tower, the cold source side outlet is connected to the desorption tower, and the heat source side inlet is connected to the reboiler;

[0042] A high-temperature waste heat exchanger, wherein the heat source side inlet is connected to the heat source side outlet of the lean-rich liquid heat exchanger, the heat source side outlet of the high-temperature waste heat exchanger is connected to the alcoholamine solution storage tank, the cold source side inlet of the high-temperature waste heat exchanger is connected to the cold storage tank for heat exchange, and the cold source side outlet is connected to the heat storage tank for heat exchange.

[0043] Compared with the prior art, the present invention has the following advantages and technical effects:

[0044] In the present invention, the captured carbon dioxide is stored in depleted oil and gas reservoirs, which can significantly reduce the storage cost of carbon dioxide, and the high-temperature geothermal energy in the depleted oil and gas reservoirs can be used to heat the carbon dioxide to increase the temperature of the carbon dioxide, avoid heating the carbon dioxide by fossil fuels, and reduce the number of heat exchangers in the system, thereby improving the system efficiency. The carbon dioxide capture system is coupled to the carbon dioxide energy storage system, and the carbon dioxide captured by the carbon dioxide capture system is directly injected into the low-pressure gas chamber of the depleted oil and gas reservoir or injected into the high-pressure gas chamber of the depleted oil and gas reservoir after being compressed by an energy replenishment compressor to replenish formation energy, maintain formation pressure stability during the energy storage and release stages, and improve system operation stability. At the same time, the degassing time in the energy release stage can be increased to improve system efficiency, and the cold / heat generated during the system operation process is recycled and reused through the waste heat utilization unit to further improve system performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor:

[0046] Figure 1 It is a schematic diagram of the system of the present invention;

[0047] Among them, 1. Carbon dioxide absorption tower; 2. Lean and rich liquid heat exchanger; 3. Desorption tower; 4. Reboiler; 5. High-temperature waste heat exchanger; 6. Amine solution storage tank; 7. Energy replenishment compressor; 8. Low-pressure compressor; 9. Medium-pressure compressor; 10. High-pressure compressor; 11. First interstage cooler; 12. Second interstage cooler; 13. High-pressure injection well; 14. High-pressure recovery well; 15. High-pressure throttle valve; 16. High-pressure expander; 17. Medium-pressure expander; 18. Low-pressure expander; 19. First interstage reheater; 20. Second interstage reheater; 21. Low-pressure injection well; 22. Low-pressure recovery well; 23. Low-pressure throttle valve; 24. Cooler; 25. Cold storage tank; 26. Heat storage tank. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0050] Reference Figure 1 The present invention discloses a transcritical carbon dioxide energy storage system based on carbon dioxide capture and utilization, comprising:

[0051] CO2 capture system for capturing CO2;

[0052] The high-pressure gas chamber of the depleted oil and gas reservoir is used to store high-pressure carbon dioxide. The high-pressure gas chamber of the depleted oil and gas reservoir is connected to the carbon dioxide capture system through the energy replenishment compressor 7;

[0053] A low-pressure gas chamber in a depleted oil and gas reservoir is used to store low-pressure carbon dioxide, and the low-pressure gas chamber in the depleted oil and gas reservoir is connected to a carbon dioxide capture system;

[0054] An energy release unit is used to release the energy in the carbon dioxide, the air inlet of the energy release unit is connected to the high-pressure air chamber of the depleted oil and gas reservoir, and the air outlet of the energy release unit is connected to the low-pressure air chamber of the depleted oil and gas reservoir;

[0055] An energy storage unit is used to store energy in carbon dioxide, wherein an air inlet of the energy storage unit is connected to a low-pressure air chamber of a depleted oil and gas reservoir, and an air outlet of the energy storage unit is connected to a high-pressure air chamber of the depleted oil and gas reservoir;

[0056] An interstage cooling unit is arranged in the energy storage unit;

[0057] An interstage reheat unit is arranged in the energy release unit;

[0058] The waste heat utilization unit is used to utilize the cold / heat generated by the interstage cooling unit, interstage reheat unit and carbon dioxide capture system.

[0059] To further optimize the scheme, the high pressure gas chamber of the depleted oil and gas reservoir is connected with:

[0060] A high-pressure injection well 13, used to inject high-pressure carbon dioxide into the high-pressure gas chamber of the depleted oil and gas reservoir, and the high-pressure injection well 13 is connected to the energy replenishment compressor 7 and the energy storage unit;

[0061] The high-pressure recovery well 14 is used to release the high-pressure carbon dioxide in the high-pressure gas chamber of the depleted oil and gas reservoir. The high-pressure recovery well 14 is connected to the energy release unit.

[0062] To further optimize the scheme, the low-pressure gas chambers of the depleted oil and gas reservoirs are connected to:

[0063] A low-pressure injection well 21, used to inject low-pressure carbon dioxide into the low-pressure gas chamber of the depleted oil and gas reservoir, and the low-pressure injection well 21 is connected to the carbon dioxide capture system and the energy release unit;

[0064] The low-pressure recovery well 22 is used to release the low-pressure carbon dioxide in the low-pressure gas chamber of the depleted oil and gas reservoir. The low-pressure recovery well 22 is connected to the energy storage unit.

[0065] To further optimize the solution, the energy release unit includes:

[0066] The high-pressure expander 16, the medium-pressure expander 17, and the low-pressure expander 18 are connected in sequence. The high-pressure expander 16 is connected to the high-pressure recovery well 14, and the low-pressure expander 18 is connected to the low-pressure injection well 21. The high-pressure carbon dioxide passes through the high-pressure expander 16, the medium-pressure expander 17, and the low-pressure expander 18 in sequence to perform work and generate electricity. The expanded low-pressure carbon dioxide enters the low-pressure gas chamber of the depleted oil and gas reservoir through the low-pressure injection well 21 for storage. The interstage reheat unit is arranged between the high-pressure expander 16, the medium-pressure expander 17, and the low-pressure expander 18. The interstage reheat unit heats the expanded carbon dioxide through the waste heat utilization unit, and at the same time stores the cold energy generated during the expansion of the carbon dioxide in the waste heat utilization unit.

[0067] A high-pressure throttle valve 15 is provided between the high-pressure expander 16 and the high-pressure recovery well 14. The function of the high-pressure throttle valve 15 is to maintain the stability of the carbon dioxide gas pressure.

[0068] To further optimize the solution, the energy storage unit includes:

[0069] A low-pressure compressor 8, a medium-pressure compressor 9, and a high-pressure compressor 10 are connected in sequence. The low-pressure compressor 8 is connected to a low-pressure recovery well 22, and the high-pressure compressor 10 is connected to a high-pressure injection well 13. Low-pressure carbon dioxide is compressed and stored in sequence by the low-pressure compressor 8, the medium-pressure compressor 9, and the high-pressure compressor 10, and then injected into the high-pressure gas chamber of the depleted oil and gas reservoir through the high-pressure injection well 13 for storage. An interstage cooling unit is arranged between the low-pressure compressor 8, the medium-pressure compressor 9, and the high-pressure compressor 10. The interstage cooling unit cools the compressed carbon dioxide gas through a waste heat utilization unit, and at the same time stores the heat generated during the compression of carbon dioxide in the waste heat utilization unit.

[0070] Among them, a low-pressure throttle valve 23 and a cooler 24 are sequentially arranged between the low-pressure recovery well 22 and the low-pressure compressor 8. The function of the low-pressure throttle valve 23 and the cooler 24 is to maintain the pressure and stability of the carbon dioxide gas.

[0071] Further optimization scheme, the interstage reheat unit includes:

[0072] The first interstage reheater 19 is arranged between the high-pressure expander 16 and the medium-pressure expander 17;

[0073] The second interstage reheater 20 is arranged between the intermediate pressure expander 17 and the low pressure expander 18;

[0074] The first inter-stage reheater 19 and the second inter-stage reheater 20 are both connected to the waste heat utilization unit for heat exchange.

[0075] The high-pressure expander 16 is connected to the cold source side inlet of the first interstage reheater 19, the medium-pressure expander 17 is connected to the cold source side outlet of the first interstage reheater 19, the medium-pressure expander 17 is connected to the cold source side inlet of the second interstage reheater 20, the low-pressure expander 18 is connected to the cold source side outlet of the second interstage reheater 20, the heat source side inlet of the first interstage reheater 19 and the second interstage reheater 20 is connected to the heat storage tank 26, and the heat source side outlet of the first interstage reheater 19 and the second interstage reheater 20 is connected to the cold storage tank 25.

[0076] To further optimize the solution, the interstage cooling unit includes:

[0077] A first interstage cooler 11 is provided between the low-pressure compressor 8 and the medium-pressure compressor 9;

[0078] A second interstage cooler 12 is provided between the intermediate pressure compressor 9 and the high pressure compressor 10;

[0079] The first interstage cooler 11 and the second interstage cooler 12 are both connected to the waste heat utilization unit for heat exchange.

[0080] The outlet of the low-pressure compressor 8 is connected to the heat source side inlet of the first interstage cooler 11, the outlet of the medium-pressure compressor 9 is connected to the heat source side inlet of the second interstage cooler 12, the heat source side outlet of the first interstage cooler 11 is connected to the inlet of the medium-pressure compressor 9, the heat source side outlet of the second interstage cooler 12 is connected to the inlet of the high-pressure compressor 10, the cold source side inlets of the first interstage cooler 11 and the second interstage cooler 12 are connected to the cold storage tank 25, and the cold source side outlets of the first interstage cooler 11 and the second interstage cooler 12 are connected to the heat storage tank 26.

[0081] To further optimize the solution, the waste heat utilization unit includes:

[0082] The cold storage tank 25 has a cold storage end connected to the first interstage reheater 19, the second interstage reheater 20 and the hot user for heat exchange, and a cold discharge end connected to the first interstage cooler 11, the second interstage cooler 12 and the cold user for heat exchange;

[0083] The heat storage tank 26 has a heat storage end connected to the first interstage cooler 11, the second interstage cooler 12 and the cold user for heat exchange, and a heat release end connected to the first interstage reheater 19, the second interstage reheater 20 and the hot user for heat exchange.

[0084] Further optimizing the scheme, the CO2 capture system includes:

[0085] Carbon dioxide absorption tower 1;

[0086] The alcoholamine solution storage tank 6 is connected to the top liquid inlet of the carbon dioxide absorption tower 1, and the alcoholamine solution storage tank 6 sends the alcoholamine lean liquid into the carbon dioxide absorption tower 1 to absorb carbon dioxide;

[0087] The top inlet of the desorption tower 3 is connected to the bottom liquid outlet of the carbon dioxide absorption tower 1, and the top outlet of the desorption tower 3 is connected to the energy replenishment compressor 7 and the low-pressure injection well 21;

[0088] A reboiler 4 is connected to the bottom outlet and the bottom inlet of the desorption tower 3;

[0089] The lean-rich liquid heat exchanger 2 has a cold source side inlet connected to the carbon dioxide absorption tower 1, a cold source side outlet connected to the desorption tower 3, and a heat source side inlet connected to the reboiler 4;

[0090] The heat source side inlet of the high-temperature waste heat exchanger 5 is connected to the heat source side outlet of the lean-rich liquid heat exchanger 2, the heat source side outlet of the high-temperature waste heat exchanger 5 is connected to the amine solution storage tank 6, the cold source side inlet of the high-temperature waste heat exchanger 5 is connected to the cold storage tank 25 for heat exchange, and the cold source side outlet is connected to the heat storage tank 26 for heat exchange.

[0091] Specific workflow:

[0092] Carbon dioxide capture: The industrially emitted carbon dioxide flue gas is transported to the bottom entrance of the carbon dioxide absorption tower 1 after denitration and desulfurization. The flue gas at the bottom of the carbon dioxide absorption tower 1 is countercurrently contacted with the lean alcoholamine solution (the alcoholamine solution that has not absorbed carbon dioxide is called lean liquid) flowing down from the top of the tower to absorb carbon dioxide. Among them, the flue gas with carbon dioxide removed is discharged from the top of the carbon dioxide absorption tower 1; the alcoholamine rich liquid is sent to the desorption tower 3 for desorption and regeneration after heat exchange treatment in the lean-rich liquid heat exchanger 2 (the operating temperature of the carbon dioxide absorption tower 1 is lower than that of the desorption tower 3, so it needs to be heated by the lean-rich liquid heat exchanger 2). In the desorption process, the rich liquid is decomposed by steam heating in the desorption tower 3, and the alcoholamine and carbon dioxide are regenerated. At this time, part of the alcohol amine solution that has not absorbed carbon dioxide is discharged through the bottom of the desorption tower 3, enters the reboiler 4 for heating again to completely desorb carbon dioxide, and the desorbed carbon dioxide enters the desorption tower 3 and is discharged from the top of the desorption tower 3, and is directly injected into the low-pressure gas chamber of the depleted oil and gas reservoir through the low-pressure injection well 21 or is injected into the high-pressure gas chamber of the depleted oil and gas reservoir after being pressurized by the energy replenishment compressor 7; the desorbed alcohol amine solution is again passed into the lean-rich liquid heat exchanger 2 and the high-temperature waste heat exchanger 5 to be cooled to a temperature equivalent to that of the flue gas, and then stored in the alcohol amine solution storage tank 6 for recovery, to be reused when the capture system is operated next time.

[0093] Energy storage: During the low electricity consumption period, the carbon dioxide in the low-pressure recovery well 22 is released, and the temperature and pressure of the carbon dioxide gas are maintained stable through the low-pressure throttle valve 23 and the cooler 24. After that, the carbon dioxide is compressed to a high temperature and high pressure state through the low-pressure compressor 8, the medium-pressure compressor 9 and the high-pressure compressor 10 in sequence. During this period, the cold storage tank 25 releases the cooling medium, and the heat generated by the compressed carbon dioxide gas is recovered and stored in the heat storage tank 26 through the first interstage cooler 11 and the second interstage cooler 12. The high-pressure carbon dioxide gas is injected into the high-pressure gas chamber of the depleted oil and gas reservoir from the high-pressure injection well 13. This is the energy storage process of the carbon dioxide energy storage system. While the energy storage process is in progress, the carbon dioxide captured in the carbon dioxide capture system is injected into the low-pressure gas chamber of the depleted oil and gas reservoir from the low-pressure injection well to ensure that the outlet pressure of the low-pressure recovery well 22 is constant and improve the system performance.

[0094] Energy release: During the peak period of electricity consumption, the high-pressure recovery well 14 releases high-temperature and high-pressure carbon dioxide. After the pressure is stabilized by the high-pressure throttle valve 15, it passes through the high-pressure expander 16, the medium-pressure expander 17 and the low-pressure expander 18 in sequence to generate power. During this period, the first inter-stage reheater 19 and the second inter-stage reheater 20 use the compression heat stored in the heat storage tank 26 to further heat the carbon dioxide, thereby improving the work capacity of the carbon dioxide and thus improving the system efficiency. The carbon dioxide that has done work is injected into the low-pressure gas chamber of the depleted oil and gas reservoir by the low-pressure injection well 21. While the energy release process is in progress, the carbon dioxide captured by the carbon dioxide capture system is compressed by the energy supplement compressor 7 and then injected into the high-pressure gas chamber of the depleted oil and gas reservoir by the high-pressure injection well 13 to ensure that the outlet pressure of the high-pressure recovery well 14 is constant and improve the system performance.

[0095] At the same time, the transcritical carbon dioxide energy storage system of the present invention uses depleted oil and gas reservoirs as gas storage reservoirs to store carbon dioxide, and can use geothermal energy to heat carbon dioxide. The system can use more thermal energy, and can achieve trigeneration of cooling, heat and electricity. Therefore, the heat energy in the heat storage tank 26 can be supplied to heat users, and the cold energy can be recovered and stored in the cold storage tank 25. The cold energy in the cold storage tank 25 can be supplied to cold users, and the heat energy can be recovered and stored in the heat storage tank 26.

[0096] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0097] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A transcritical carbon dioxide energy storage system based on carbon dioxide capture and utilization, characterized in that: include: CO2 capture system for capturing CO2; A high-pressure gas chamber of a depleted oil and gas reservoir, used for storing high-pressure carbon dioxide, wherein the high-pressure gas chamber of the depleted oil and gas reservoir is connected to the carbon dioxide capture system via an energy replenishment compressor (7); A low-pressure gas chamber in a depleted oil and gas reservoir, used for storing low-pressure carbon dioxide, wherein the low-pressure gas chamber in the depleted oil and gas reservoir is connected to the carbon dioxide capture system; An energy release unit, used to release the energy in the carbon dioxide, wherein the air inlet of the energy release unit is connected to the high-pressure air chamber of the depleted oil and gas reservoir, and the air outlet of the energy release unit is connected to the low-pressure air chamber of the depleted oil and gas reservoir; An energy storage unit, used to store energy in carbon dioxide, wherein an air inlet of the energy storage unit is connected to a low-pressure air chamber of the depleted oil and gas reservoir, and an air outlet of the energy storage unit is connected to a high-pressure air chamber of the depleted oil and gas reservoir; An interstage cooling unit, arranged in the energy storage unit; An interstage reheat unit, arranged in the energy release unit; A waste heat utilization unit is used to utilize the cold / heat generated by the interstage cooling unit, the interstage reheat unit and the carbon dioxide capture system.

2. A transcritical carbon dioxide energy storage system based on carbon dioxide capture and utilization according to claim 1, characterized in that: The high-pressure gas chamber of the depleted oil and gas reservoir is connected with: A high-pressure injection well (13), used for injecting high-pressure carbon dioxide into the high-pressure gas chamber of the depleted oil and gas reservoir, wherein the high-pressure injection well (13) is connected to the energy replenishment compressor (7) and the energy storage unit; The high-pressure recovery well (14) is used to release the high-pressure carbon dioxide in the high-pressure gas chamber of the depleted oil and gas reservoir, and the high-pressure recovery well (14) is connected to the energy release unit.

3. A transcritical carbon dioxide energy storage system based on carbon dioxide capture and utilization according to claim 2, characterized in that: The low-pressure gas chamber of the depleted oil and gas reservoir is connected with: A low-pressure injection well (21) is used to inject low-pressure carbon dioxide into the low-pressure gas chamber of the depleted oil and gas reservoir, and the low-pressure injection well (21) is connected to the carbon dioxide capture system and the energy release unit; A low-pressure recovery well (22) is used to release the low-pressure carbon dioxide in the low-pressure gas chamber of the depleted oil and gas reservoir, and the low-pressure recovery well (22) is connected to the energy storage unit.

4. A transcritical carbon dioxide energy storage system based on carbon dioxide capture and utilization according to claim 3, characterized in that: The energy release unit comprises: A high-pressure expander (16), a medium-pressure expander (17), and a low-pressure expander (18) are sequentially connected, the high-pressure expander (16) is connected to the high-pressure recovery well (14), and the low-pressure expander (18) is connected to the low-pressure injection well (21). High-pressure carbon dioxide sequentially passes through the high-pressure expander (16), the medium-pressure expander (17), and the low-pressure expander (18) to generate power, and the expanded low-pressure carbon dioxide passes through the low-pressure injection well (21) and enters the low-pressure gas chamber of the depleted oil and gas reservoir for storage. The interstage reheat unit is arranged between the high-pressure expander (16), the medium-pressure expander (17), and the low-pressure expander (18). The interstage reheat unit heats the expanded carbon dioxide through the waste heat utilization unit, and at the same time stores the cold energy generated during the expansion of the carbon dioxide in the waste heat utilization unit.

5. A transcritical carbon dioxide energy storage system based on carbon dioxide capture and utilization according to claim 4, characterized in that: The energy storage unit comprises: A low-pressure compressor (8), a medium-pressure compressor (9), and a high-pressure compressor (10) are sequentially connected, the low-pressure compressor (8) is connected to the low-pressure recovery well (22), and the high-pressure compressor (10) is connected to the high-pressure injection well (13). Low-pressure carbon dioxide is compressed and stored in sequence by the low-pressure compressor (8), the medium-pressure compressor (9), and the high-pressure compressor (10), and then injected into the high-pressure gas chamber of the depleted oil and gas reservoir through the high-pressure injection well (13) for storage. The interstage cooling unit is arranged between the low-pressure compressor (8), the medium-pressure compressor (9), and the high-pressure compressor (10). The interstage cooling unit cools the compressed carbon dioxide gas through the waste heat utilization unit, and at the same time stores the heat generated during the compression of the carbon dioxide in the waste heat utilization unit.

6. A transcritical carbon dioxide energy storage system based on carbon dioxide capture and utilization according to claim 5, characterized in that: The interstage reheat unit comprises: a first inter-stage reheater (19) disposed between the high-pressure expander (16) and the medium-pressure expander (17); a second interstage reheater (20) disposed between the intermediate pressure expander (17) and the low pressure expander (18); The first inter-stage reheater (19) and the second inter-stage reheater (20) are both connected to the waste heat utilization unit for heat exchange.

7. A transcritical carbon dioxide energy storage system based on carbon dioxide capture and utilization according to claim 6, characterized in that: The interstage cooling unit comprises: A first interstage cooler (11) is arranged between the low-pressure compressor (8) and the medium-pressure compressor (9); a second interstage cooler (12) disposed between the intermediate-pressure compressor (9) and the high-pressure compressor (10); The first interstage cooler (11) and the second interstage cooler (12) are both connected to the waste heat utilization unit for heat exchange.

8. A transcritical carbon dioxide energy storage system based on carbon dioxide capture and utilization according to claim 7, characterized in that: The waste heat utilization unit comprises: A cold storage tank (25), wherein a cold storage end is connected to the first interstage reheater (19), the second interstage reheater (20) and a hot user by heat exchange, and a cold discharge end is connected to the first interstage cooler (11), the second interstage cooler (12) and a cold user by heat exchange; A heat storage tank (26), wherein a heat storage end is connected to the first interstage cooler (11), the second interstage cooler (12) and the cold user for heat exchange, and a heat release end is connected to the first interstage reheater (19), the second interstage reheater (20) and the hot user for heat exchange.

9. A transcritical carbon dioxide energy storage system based on carbon dioxide capture and utilization according to claim 8, characterized in that: The carbon dioxide capture system comprises: Carbon dioxide absorption tower (1); The alcoholamine solution storage tank (6) is connected to the top liquid inlet of the carbon dioxide absorption tower (1), and the alcoholamine solution storage tank (6) sends the alcoholamine lean liquid into the carbon dioxide absorption tower (1) to absorb carbon dioxide; A desorption tower (3), the top inlet of which is connected to the bottom liquid outlet of the carbon dioxide absorption tower (1), and the top outlet of the desorption tower (3) is connected to the energy replenishment compressor (7) and the low-pressure injection well (21); A reboiler (4) is connected to the bottom outlet and the bottom inlet of the desorption tower (3); A lean-rich liquid heat exchanger (2), wherein the cold source side inlet is connected to the carbon dioxide absorption tower (1), the cold source side outlet is connected to the desorption tower (3), and the heat source side inlet is connected to the reboiler (4); The high-temperature waste heat exchanger (5) has a heat source side inlet connected to the heat source side outlet of the lean-rich liquid heat exchanger (2), the heat source side outlet of the high-temperature waste heat exchanger (5) is connected to the alcohol amine solution storage tank (6), the cold source side inlet of the high-temperature waste heat exchanger (5) is connected to the cold storage tank (25) for heat exchange, and the cold source side outlet is connected to the heat storage tank (26) for heat exchange.

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