Device for high-pressure gas liquefaction-evaporation circulation and energy storage and release method

Abstract

The invention relates to a device for high-pressure gas liquefaction-evaporation circulation and an energy storage and release method, and belongs to the technical field of energy storage. According to the device, a gas circulation loop comprises a compression side passage, an expansion side passage and a connecting passage, one end of the connecting passage is connected with the compression side passage, the other end of the connecting passage is connected with the expansion side passage, a first heat exchanger is arranged on the connecting passage, and the compression side passage communicates with the expansion side passage through the first heat exchanger; a compression cooling module and a heat pump evaporator are sequentially arranged on the compression side passage, the compression cooling module is communicated with the third liquid loop and the compression side passage, and the heat pump evaporator is communicated with the first liquid loop and the compression side passage; a second heat exchanger and a heating expansion module are sequentially arranged on the expansion side passage, and the second heat exchanger communicates with the third liquid loop and the expansion side passage. Through the arrangement of the first liquid loop and the third liquid loop, heat transfer and storage between the energy storage process and the energy release process are completed, and a cold accumulator in the traditional gas evaporation and condensation process is replaced.

Description

Technical Field

[0001] The present invention belongs to the field of energy storage technology, and in particular relates to a device for high-pressure gas liquefaction-evaporation cycle and an energy storage and release method. Background Art

[0002] At present, compressed CO2 energy storage can be divided into liquid-liquid-compressed CO2 energy storage, gas-liquid-compressed CO2 energy storage, and gas-gas-compressed CO2 energy storage according to the storage method of CO2. Gas-gas-compressed CO2 energy storage occupies a large space and it is difficult to achieve a good balance between thermodynamic performance and economic performance. For liquid-liquid-compressed CO2 energy storage, the liquid storage of CO2 can greatly reduce the volume of the gas tank, but it involves the evaporation and condensation process of CO2. However, due to the physical constraints of CO2, the liquid storage temperature of CO2 on the low-pressure side is relatively low, which may form dry ice and block the pipeline. At the same time, it is limited by the critical point of CO2, and the pressure of the liquid-liquid-compressed CO2 energy storage system is relatively low, which reduces the work capacity per unit mass of CO2.

[0003] Compared with the above two types of energy storage systems, gas-liquid-compressed CO2 energy storage has been widely used in practical engineering. The low-pressure side of this type of system adopts normal pressure flexible storage to significantly reduce the unit volume cost of the gas storage, while significantly increasing the pressure ratio of the system, greatly improving the work capacity of high-pressure CO2. On the high-pressure side, in order to reduce the volume of the storage tank, CO2 liquid storage is adopted. In order to realize the gas-liquid conversion process of CO2 on the high-pressure side, the existing solution usually installs a cold storage device in the system, that is, a certain amount of cold is collected during the expansion process for the liquefaction of CO2 during the compression process. However, the cold storage device is unstable in operation, bulky, and expensive. At the same time, in order to meet the heat transfer of the cold storage device, the high-pressure liquid CO2 must be throttled during the energy release process. Therefore, how to store CO2 phase change energy efficiently and at low cost needs to be solved urgently. Summary of the Invention

[0004] In response to the above problems, the present invention provides a device for high-pressure gas liquefaction-evaporation cycle and an energy storage and release method.

[0005] A first object of the present invention is to provide an apparatus for a high-pressure gas liquefaction-evaporation cycle, comprising: a gas circulation loop, a first liquid loop, and a third liquid loop; The gas circulation circuit includes a compression side passage, an expansion side passage, and a connecting passage, one end of the connecting passage is connected to the compression side passage, and the other end is connected to the expansion side passage. A first heat exchanger is provided on the connecting passage, and the compression side passage and the expansion side passage are connected through the first heat exchanger; The compression side passage is provided with a compression cooling module and a heat pump evaporator in sequence, the compression cooling module is connected to the third liquid circuit and the compression side passage, and the heat pump evaporator is connected to the first liquid circuit and the compression side passage; The expansion side passage is provided with a second heat exchanger and a heating and expansion module in sequence, and the second heat exchanger is connected with the third liquid circuit and the expansion side passage; The first liquid circuit is a circulation circuit for liquid evaporation, pressurized cooling and throttling; The third liquid loop is a circulation loop for liquid heating and cooling.

[0006] In a specific embodiment of the present invention, the device further comprises a second liquid circuit, wherein the second liquid circuit is a circulation circuit for liquid heating and cooling; The expansion side passage is further provided with a third heat exchanger, and heat is exchanged with the second liquid circuit through the third heat exchanger; In the flow direction of the high-pressure liquid gas, the third heat exchanger is located before the heating and expansion module.

[0007] In a specific embodiment of the present invention, a heat pump condenser is provided on the first liquid circuit, and is connected to the second liquid circuit through the heat pump condenser.

[0008] In a specific embodiment of the present invention, the second liquid circuit is further provided with a second cold liquid tank and a second hot liquid tank; The second cold liquid tank and the second hot liquid tank are respectively arranged on two communication lines between the third heat exchanger and the heat pump condenser.

[0009] In a specific embodiment of the present invention, a water pump is further provided on the two communication lines between the third heat exchanger and the heat pump condenser.

[0010] In a specific embodiment of the present invention, a compressor is further provided on the first liquid circuit, and the compressor is arranged between the heat pump evaporator and the heat pump condenser.

[0011] In a specific embodiment of the present invention, a throttle valve is provided between the compressor and the heat pump condenser.

[0012] In a specific embodiment of the present invention, the third liquid circuit is formed by a first passage, a second passage, and a third passage that are interconnected, and a second heat exchanger is further provided on the expansion side passage; The first passage is connected to the second passage through the compression and cooling module, the first passage is connected to the third passage through the heating and expansion module, and the second passage is connected to the third passage through the second heat exchanger; In the flow direction of the high-pressure liquid gas, the second heat exchanger is located before the heating and expansion module.

[0013] In a specific embodiment of the present invention, a first hot liquid tank is provided on the first passage; The second passage is provided with a first cold liquid tank and a cooler, and the cooler is close to the compression cooling module.

[0014] In a specific embodiment of the present invention, water pumps are provided on both the first passage and the second passage.

[0015] A second object of the present invention is to provide an energy storage and release method for a high-pressure gas liquefaction-evaporation cycle device based on the above, including an energy storage method, the energy storage method comprising: The low-pressure gas circulates in the compression side passage of the gas circulation loop, passing through the compression cooling module and the heat pump evaporator in turn. The gas is compressed and cooled by the compression cooling module, and the gas is liquefied by the heat pump evaporator to obtain high-pressure liquid and store it to achieve energy storage.

[0016] In a specific embodiment of the present invention, during the energy storage process: The third liquid circuit provides the cooling liquid required for cooling the compression cooling module, and at the same time absorbs and stores the heat generated by the compression cooling module; The first liquid loop provides the heat pump evaporator with the low-temperature liquid required for liquefaction and evaporates the low-temperature liquid into gas. At the same time, the evaporated gas completes the cycle of compression, cooling, liquefaction and evaporation in the first loop.

[0017] In a specific embodiment of the present invention, during the energy storage process: The second liquid circuit absorbs and stores heat generated during liquefaction in the first liquid circuit.

[0018] In a specific embodiment of the present invention, the energy storage and release method further includes an energy release method, and the energy release method includes: High-pressure liquid gas circulates in the expansion side passage of the gas circulation loop, passes through the first heat exchanger and the heating expansion module, and is preheated by the first heat exchanger. The liquid gas is heated and expanded by the heating expansion module to obtain low-pressure gas, and returns to the compression side passage through the connecting passage to release energy.

[0019] In a specific embodiment of the present invention, during the energy release process: The third liquid loop provides the heat required for the thermal expansion module to heat and expand; The second liquid loop provides the heat required for preheating the first heat exchanger.

[0020] In a specific embodiment of the present invention, during the energy release process: The high-pressure liquid gas is preheated multiple times while circulating in the expansion side passage; The primary preheating is achieved by the second heat exchanger, and the heat required for heating by the second heat exchanger is provided by the third liquid path; The primary preheating is achieved by the third heat exchanger, and the heat required for heating the third heat exchanger is provided by the second liquid circuit.

[0021] Beneficial effects of the present invention: The device for high-pressure gas liquefaction-evaporation cycle and the energy storage and release method of the present invention achieve energy storage and recycling through the provision of the first liquid circuit, reduce the problems of high-pressure liquid gas, avoid lowering the liquid gas temperature by throttling the high-pressure liquid gas, and avoid pressure loss. By setting up the first liquid circuit and the third liquid circuit, heat transfer and storage between the energy storage and energy release processes are completed. The combined use of the two replaces the cold storage device in the traditional gas evaporation and condensation process, ensuring the stability of the gas pressurization liquefaction and heating expansion process.

[0022] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces 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.

[0024] Figure 1 A flow chart of an apparatus for high-pressure gas liquefaction-evaporation cycle according to an embodiment of the present invention is shown; In the figure: 10, compression side passage; 11, low-pressure storage module; 12, first valve; 13, compression cooling module; 14, second valve; 15, third valve; 16, high-pressure liquid storage module; 17, fourth valve; 20. First passage; 21. Fifth valve; 22. First hot liquid tank; 23. Sixth valve; 24. First water pump; 25. Seventh valve; 30. Second passage; 31. Eighth valve; 32. Second water pump; 33. Ninth valve; 34. Cooler; 35. Tenth valve; 36. First cold liquid tank; 37. Eleventh valve; 40. Expansion side passage; 41. 12th valve; 42. 13th valve; 43. 14th valve; 44. Heating expansion module; 45. 15th valve; 50. First liquid circuit; 51. Throttle valve; 52. Sixteenth valve; 53. Seventeenth valve; 54. Compressor; 55. Eighteenth valve; 56. Nineteenth valve; 60, second liquid circuit; 61, third water pump; 62, 20th valve; 63, second cold liquid tank; 64, 21st valve; 65, 22nd valve; 66, fourth water pump; 67, 23rd valve; 68, second hot liquid tank; 69, 24th valve; 691, 25th valve; 70. Third passage; 71. Twenty-sixth valve; 80, fourth passage; 81, twenty-seventh valve; 90, Fifth Passage; 201. Heat pump evaporator; 202. First heat exchanger; 203. Second heat exchanger; 204. Third heat exchanger; 205. Heat pump condenser. DETAILED DESCRIPTION

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings 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 making creative efforts shall fall within the scope of protection of the present invention.

[0026] like Figure 1 As shown, a device for high-pressure gas liquefaction-evaporation cycle according to some embodiments of the present invention includes: a gas circulation loop, a first liquid loop 50 and a third liquid loop; The gas circulation loop includes a compression side passage 10, an expansion side passage 40, and a connecting passage. One end of the connecting passage is connected to the compression side passage 10, and the other end is connected to the expansion side passage 40. A first heat exchanger 202 is provided on the connecting passage. The compression side passage 10 and the expansion side passage 40 are connected via the first heat exchanger 202. The compression side passage 10 is provided with a compression cooling module 13 and a heat pump evaporator 201 in sequence. The compression cooling module 13 is connected to the third liquid circuit and the compression side passage 10. The heat pump evaporator 201 is connected to the first liquid circuit 50 and the compression side passage 10. The expansion side passage 40 is provided with a second heat exchanger 203 and a heating expansion module 44 in sequence, and the second heat exchanger 203 connects the third liquid circuit and the expansion side passage 40; The compression side passage 10 is used to pressurize, cool and liquefy the low-pressure gas, so that the low-pressure gas is converted into a high-pressure liquid; The expansion side passage 40 is used to preheat and heat the high-pressure liquid to expand it, so that the high-pressure liquid is converted into low-pressure gas. The low-pressure gas returns to the compression side passage 10 through the connecting passage, forming a gas circulation loop. The first liquid circuit 50 is a circulation circuit for liquid evaporation, pressurized cooling, and throttling. By configuring the first liquid circuit 50, the cooling liquid required for liquefaction in the compression side passage 10 (the cooling liquid required by the heat pump evaporator 201) is simultaneously evaporated by the heat pump evaporator 201, and then pressurized, cooled, and liquefied before being converted back into liquid for use by the heat pump evaporator 201. This achieves energy storage and recycling, reduces the problem of high-pressure liquid gas, avoids reducing the liquid gas temperature by throttling the high-pressure liquid gas, avoids pressure loss, and improves the stability of the pressurized liquefaction process. The third liquid circuit is a circulation circuit for liquid heating and cooling. By providing the third liquid, the third liquid circuit is used to provide the coolant required for pressurized cold water to the pressurized cooling and contraction module in the compression side passage 10. At the same time, the coolant absorbs heat and is converted into hot liquid. The hot liquid then provides heat for the heating and expansion in the expansion side passage 40 (that is, provides heat to the heating and expansion module 44). The hot liquid is further converted into liquid and used by the pressurized cooling and contraction module, thereby realizing energy storage and recycling, while ensuring the stability of energy conversion during the heating and expansion process of the compression side passage 10. In the embodiment of the present invention, the first liquid circuit 50 and the third liquid circuit replace the cold storage device in the traditional gas evaporation and condensation process, thereby ensuring the stability of the gas pressurization liquefaction and heating expansion process.

[0027] In some embodiments of the present invention, the compression side passage 10 is further provided with a low-pressure storage module 11 and a high-pressure liquid storage module 16; In the flow direction of the low-pressure gas, the low-pressure storage module 11, the compression cooling module 13, and the high-pressure liquid storage module 16 are connected in sequence; The low-pressure storage module 11 is used to store low-pressure gas, and the high-pressure liquid storage module 16 is used to store high-pressure liquid gas.

[0028] In certain embodiments of the present invention, the device further comprises a second liquid circuit 60, which is a circulation circuit for liquid heating and cooling; The first liquid circuit 50 is provided with a heat pump condenser 205 and is connected to the second liquid circuit 60 through the heat pump condenser 205. The heat pump condenser 205 is a heat exchanger between the first liquid circuit 50 and the second liquid circuit 60. Its functions are: first, to release heat and cool the gas obtained by evaporation in the first liquid circuit 50, so that the gas is cooled into liquid; second, to convert the heat generated in the heat release process of the gas obtained by evaporation into hot liquid in the second liquid circuit 60, that is, through the heat pump condenser 205, it is further facilitated to recover and store the heat generated during the liquefaction in the first liquid circuit.

[0029] In some embodiments of the present invention, a third heat exchanger 204 is further provided on the expansion side passage 40, and heat is exchanged with the second liquid circuit 60 through the third heat exchanger 204. In the flow direction of the high-pressure liquid gas, the third heat exchanger 204 is located before the heating and expansion module 44; By providing the third heat exchanger 204 , the heat absorbed by the second liquid circuit 60 from the first liquid circuit 50 is used as energy for preheating the high-pressure liquid gas.

[0030] In some embodiments of the present invention, the second liquid circuit 60 is further provided with a second cold liquid tank 63 and a second hot liquid tank 68 to facilitate storage of the hot liquid and the cold liquid formed in the second liquid circuit 60; The second cold liquid tank 63 and the second hot liquid tank 68 are respectively disposed on two communication lines between the third heat exchanger 204 and the heat pump condenser 205 .

[0031] In some embodiments of the present invention, a water pump is further provided on the two communication lines between the third heat exchanger 204 and the heat pump condenser 205 to facilitate the circulation of the liquid in the second liquid circuit 60; The water pumps on the two communication lines between the third heat exchanger 204 and the heat pump condenser 205 are illustratively a third water pump 61 and a fourth water pump 66 . The third water pump 61 is located on the cold liquid flow path, and the fourth water pump 66 is located on the hot liquid flow path.

[0032] In certain embodiments of the present invention, a compressor 54 is further provided on the first liquid circuit 50. The compressor 54 is disposed between the heat pump evaporator 201 and the heat pump condenser 205. The arrangement of the compressor 54 facilitates pressurization and cooling of the evaporated liquid.

[0033] In some embodiments of the present invention, a throttle valve 51 is provided between the compressor 54 and the heat pump condenser 205 to reduce the pressure of the pressurized and cooled liquid to facilitate subsequent evaporation of the liquid by the heat pump evaporator 201 .

[0034] In some embodiments of the present invention, the third liquid circuit is formed by a first passage 20, a second passage 30, and a third passage 70 that are interconnected, and a second heat exchanger 203 is further provided on the expansion side passage 40; The first passage 20 is connected to the second passage 30 through the compression cooling module 13 , the first passage 20 is connected to the third passage 70 through the heating and expansion module 44 , and the second passage 30 is connected to the third passage 70 through the second heat exchanger 203 ; In the flow direction of the high-pressure liquid gas, the second heat exchanger 203 is located before the heating and expansion module 44; The arrangement of the second heat exchanger 203 further utilizes the heat generated during the conversion of hot liquid into cold liquid in the third liquid loop, and uses the heat as energy for preheating the high-pressure liquid gas.

[0035] In some embodiments of the present invention, a first hot liquid tank 22 is provided on the first passage 20 for storing hot liquid generated by the third liquid circuit absorbing heat from the compression cooling module 13; The second passage 30 is provided with a first cold liquid tank 36 and a cooler 34 , and the cooler 34 is close to the compression cooling module 13 ; The first cold liquid tank 36 is used to store the cold liquid generated after the hot liquid passes through the heating expansion module 44; The cooler 34 is used to further cool the cold liquid, thereby improving the cooling effect of the liquid entering the compression cooling module 13 .

[0036] In some embodiments of the present invention, a water pump is provided on each of the first passage 20 and the second passage 30 to facilitate the flow of liquid in the third liquid circuit; The water pump on the first passage 20 is exemplarily a first water pump 24 , and the water pump on the second passage 30 is exemplarily a second water pump 32 ; In the direction of liquid circulation, the first water pump 24 is located behind the first hot liquid tank 22 ; in the direction of cold liquid circulation, the second water pump 32 is located behind the cooler 34 .

[0037] In certain embodiments of the present invention, the connecting passage is composed of a fourth passage 80 and a fifth passage 90, the fourth passage 80 and the fifth passage 90 are connected through the first heat exchanger 202, the fifth passage 90 is connected to the expansion side passage 40, and the fourth passage 80 is connected to the compression side passage 10.

[0038] In certain embodiments of the present invention, valves are provided between the above components, for example: A first valve 12 is provided between the low-pressure storage module 11 and the compression cooling module 13; A second valve 14 is provided between the compression cooling module 13 and the heat pump evaporator 201; A third valve 15 is provided between the compression cooling module 13 and the high-pressure liquid storage module 16; a fourth valve 17 provided between the high-pressure liquid storage module 16 and the first heat exchanger 202; A fifth valve 21 is provided between the compression cooling module 13 and the first hot liquid tank 22; a sixth valve 23 provided between the first hot liquid tank 22 and the first water pump 24; a seventh valve 25 provided between the first water pump 24 and the heating and expansion module 44; An eighth valve 31 is provided between the compression cooling module 13 and the second water pump 32; a ninth valve 33 provided between the second water pump 32 and the cooler 34; A tenth valve 35 is provided between the cooler 34 and the first cold liquid tank 36; an eleventh valve 37 provided between the first cold liquid tank 36 and the second heat exchanger 203; a twelfth valve 41 provided between the first heat exchanger 202 and the second heat exchanger 203; a thirteenth valve 42 provided between the second heat exchanger 203 and the third heat exchanger 204; a fourteenth valve 43 provided between the third heat exchanger 204 and the heating and expansion module 44; A fifteenth valve 45 is provided between the heating and expansion module 44 and the first heat exchanger 202. For example, in some examples of the present invention, the fifteenth valve 45 is provided on the expansion-side passage 40. The fifteenth valve 45 may also be provided on the fifth passage 90. a sixteenth valve 52 provided between the throttle valve 51 and the heat pump condenser 205; a seventeenth valve 53 provided between the heat pump condenser 205 and the compressor 54; an eighteenth valve 55 provided between the compressor 54 and the heat pump evaporator 201; a nineteenth valve 56 provided between the heat pump evaporator 201 and the throttle valve 51; a twentieth valve 62 provided between the third water pump 61 and the second cold liquid tank 63; a twenty-first valve 64 provided between the second cold liquid tank 63 and the third heat exchanger 204; A twenty-second valve 65 provided between the third heat exchanger 204 and the fourth water pump 66; A twenty-third valve 67 is provided between the fourth water pump 66 and the second hot water tank; A twenty-fourth valve 69 provided between the second hot water tank and the heat pump condenser 205; A twenty-fifth valve 691 provided between the heat pump condenser 205 and the third water pump 61 provided therebetween; a twenty-sixth valve 71 provided between the heating and expansion module 44 and the third heat exchanger 204; The twenty-seventh valve 81 is arranged between the first heat exchanger 202 and the low-pressure storage module 11. For example, in some examples of the present invention, the twenty-seventh valve 81 is arranged on the fourth passage 80, and the twenty-seventh valve 81 can also be arranged on the compression side passage 10.

[0039] In certain embodiments of the present invention, the valve is, for example, a plug valve.

[0040] In certain embodiments of the present invention, the process of converting low-pressure gas into high-pressure liquid gas in the compression side passage 10 is as follows: The low-pressure gas in the low-pressure storage module 11 enters the compression cooling module 13 , and after being pressurized and cooled, enters the heat pump evaporator 201 and is cooled and liquefied to form high-pressure liquid gas, which is finally stored in the high-pressure liquid storage module 16 .

[0041] During the process: The cooling capacity of the heat pump evaporator 201 comes from the first liquid circuit 50. The liquid in the heat pump evaporator 201 absorbs the condensation heat of the gas and evaporates into gas. The gas flows into the compressor 54 and is pressurized. The gas enters the heat pump condenser 205, where it releases heat and cools down. The gas flows through the throttle valve 51, where the pressure is reduced and the gas enters the heat pump evaporator 201 again to cool the gas. When the heat pump evaporator 201 is in operation, the cold liquid in the second liquid loop 60 flows through the heat pump condenser 205 , absorbs heat in the heat pump condenser 205 and becomes hot water, and then enters the second cold liquid tank 63 to be stored.

[0042] The cold liquid required by the compression-cooling module comes from the first cold liquid tank 36. The cold liquid in the first cold liquid tank 36 flows through the cooler 34 and the second water pump 32 in sequence, and becomes hot water after cooling the gas in the compression-cooling module, and then flows into the first hot liquid tank 22 to be stored.

[0043] In certain embodiments of the present invention, the process of converting high-pressure liquid gas into low-pressure gas in the expansion side passage 40 is as follows: The high-pressure liquid gas in the high-pressure liquid storage module 16 flows through the first heat exchanger 202, where it is preheated. After being heated by the waste heat from the preheated and expanded exhaust gas, the liquid in the first heat exchanger 202 enters the second heat exchanger 203, where it is further preheated. It then enters the third heat exchanger 204, where it is further preheated, completing the evaporation of the high-pressure liquid. The high-pressure gas then enters the heating-expansion module, where it undergoes heating and expansion. Once expansion is complete, the liquid in the expansion-side passage 40 is routed through the fourth passage 80 in the connecting passageway, recovered from the waste heat of the exhaust gas, and then returned to the low-pressure storage module 11 through the fourth and fifth passages 80 and 90 for storage.

[0044] In the above process: The heat required in the heating-expansion module comes from the first hot liquid tank 22. The hot water in the first hot liquid tank 22 passes through the first water pump 24 and enters the heating expansion module 44 to provide heat for gas heating and expansion. The hot water then turns into warm liquid, which enters the second heat exchanger 203 and then turns into cold water, enters the first cold liquid tank 36, and is stored.

[0045] The hot water in the second hot water tank of the second liquid loop 60 passes through the third water pump 61 and enters the third heat exchanger 204 to provide heat for preheating the high-pressure liquid gas. It then turns into cold water and enters the second cold water tank to be stored.

[0046] In some embodiments of the present invention, the gas is CO 2 , and the liquids in the first liquid loop 50 , the second liquid loop 60 , and the third liquid loop are all water.

[0047] According to certain embodiments of the present invention, an energy storage and release method for a device for a high-pressure gas liquefaction-evaporation cycle includes an energy storage method, the energy storage method comprising: The low-pressure gas circulates in the compression side passage 10 of the gas circulation loop, passes through the compression cooling module 13 and the heat pump evaporator 201 in sequence, and the gas is compressed and cooled by the compression cooling module 13. The gas is liquefied by the heat pump evaporator 201 to obtain high-pressure liquid and store it to achieve energy storage.

[0048] In certain embodiments of the present invention, during the energy storage process: The third liquid circuit provides the cooling liquid required for cooling the compression cooling module 13, and at the same time absorbs and stores the heat generated by the compression cooling module 13; The first liquid loop 50 provides the heat pump evaporator 201 with the cryogenic liquid required for liquefaction and evaporates the cryogenic liquid into gas. Meanwhile, the evaporated gas completes a cycle of compression, cooling, liquefaction and evaporation in the first loop.

[0049] In certain embodiments of the present invention, during the energy storage process: The second liquid circuit 60 absorbs and stores heat generated during liquefaction in the first liquid circuit 50 .

[0050] In some embodiments of the present invention, an energy release method is included, and the energy release method includes: High-pressure liquid gas circulates in the expansion-side passage 40 of the gas circulation loop, passing through the first heat exchanger 202 and the heating and expansion module 44. The liquid gas is preheated by the first heat exchanger 202 and then heated and expanded by the heating and expansion module 44 to produce low-pressure gas. The gas then returns to the compression-side passage 10 through the connecting passage, releasing energy. The heat required for heating the first heat exchanger 202 is provided by the low-pressure gas at the outlet of the heating and expansion module 44.

[0051] In certain embodiments of the present invention, during the energy release process: The third liquid loop provides the heat required for the thermal expansion module to heat and expand; The second liquid loop 60 provides heat required for preheating the first heat exchanger 204 .

[0052] In certain embodiments of the present invention, during the energy release process: The high-pressure liquid gas is preheated multiple times while circulating in the expansion side passage 40; The primary preheating is achieved by the second heat exchanger 203, and the heat required for heating by the second heat exchanger 203 is provided by the third liquid path; The primary preheating is achieved by the third heat exchanger 204 , and the heat required for heating the third heat exchanger 204 is provided by the second liquid loop 60 .

[0053] Although the present invention 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; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for high-pressure gas liquefaction-evaporation cycle, characterized in that: include: a gas circulation loop, a first liquid loop (50), and a third liquid loop; The gas circulation loop comprises a compression side passage (10), an expansion side passage (40), and a connecting passage, one end of the connecting passage being connected to the compression side passage (10), and the other end being connected to the expansion side passage (40), a first heat exchanger (202) being provided on the connecting passage, and the compression side passage (10) and the expansion side passage (40) being communicated with each other via the first heat exchanger (202); A compression cooling module (13) and a heat pump evaporator (201) are sequentially provided on the compression side passage (10); the compression cooling module (13) is connected to the third liquid circuit and the compression side passage (10); and the heat pump evaporator (201) is connected to the first liquid circuit (50) and the compression side passage (10); A second heat exchanger (203) and a heating expansion module (44) are sequentially provided on the expansion side passage (40), and the second heat exchanger (203) is connected to the third liquid circuit and the expansion side passage (40); The first liquid circuit (50) is a circulation circuit for liquid evaporation, pressurization, cooling and throttling; The third liquid loop is a circulation loop for liquid heating and cooling.

2. The device for high-pressure gas liquefaction-evaporation cycle according to claim 1, characterized in that: It also includes a second liquid circuit (60), which is a circulation circuit for liquid heating and cooling; The expansion side passage (40) is further provided with a third heat exchanger (204), and heat is exchanged with the second liquid circuit (60) through the third heat exchanger (204); In the flow direction of the high-pressure liquid gas, the third heat exchanger (204) is located before the heating and expansion module (44).

3. The device for high-pressure gas liquefaction-evaporation cycle according to claim 2, characterized in that: A heat pump condenser (205) is provided on the first liquid circuit (50), and is connected to the second liquid circuit (60) through the heat pump condenser (205).

4. The device for high-pressure gas liquefaction-evaporation cycle according to claim 3, characterized in that: The second liquid circuit (60) is further provided with a second cold liquid tank (63) and a second hot liquid tank (68); The second cold liquid tank (63) and the second hot liquid tank (68) are respectively arranged on two communication lines between the third heat exchanger (204) and the heat pump condenser (205).

5. The device for high-pressure gas liquefaction-evaporation cycle according to claim 3, characterized in that: Water pumps are also provided on the two communication lines between the third heat exchanger (204) and the heat pump condenser (205).

6. The device for high-pressure gas liquefaction-evaporation cycle according to claim 3, characterized in that: A compressor (54) is also provided on the first liquid circuit (50), and the compressor (54) is arranged between the heat pump evaporator (201) and the heat pump condenser (205).

7. The device for high-pressure gas liquefaction-evaporation cycle according to claim 6, characterized in that: A throttle valve (51) is provided between the compressor (54) and the heat pump condenser (205).

8. A device for high-pressure gas liquefaction-evaporation cycle according to any one of claims 1 to 7, characterized in that: The third liquid circuit is formed by a first passage (20), a second passage (30), and a third passage (70) that are interconnected, and a second heat exchanger (203) is further provided on the expansion side passage (40); The first passage (20) and the second passage (30) are in communication through the compression cooling module (13), the first passage (20) and the third passage (70) are in communication through the heating expansion module (44), and the second passage (30) and the third passage (70) are in communication through the second heat exchanger (203); In the flow direction of the high-pressure liquid gas, the second heat exchanger (203) is located before the heating and expansion module (44).

9. The device for high-pressure gas liquefaction-evaporation cycle according to claim 8, characterized in that: A first hot liquid tank (22) is provided on the first passage (20); A first cold liquid tank (36) and a cooler (34) are provided on the second passage (30), and the cooler (34) is close to the compression cooling module (13).

10. The device for high-pressure gas liquefaction-evaporation cycle according to claim 8, characterized in that: Water pumps are provided on both the first passage (20) and the second passage (30).

11. A method for storing and releasing energy, characterized in that: A high-pressure gas liquefaction-evaporation cycle device according to any one of claims 1 to 9 is implemented, including an energy storage method, the energy storage method comprising: The low-pressure gas circulates in the compression side passage (10) of the gas circulation loop, passes through the compression cooling module (13) and the heat pump evaporator (201) in sequence, and the gas is compressed and cooled by the compression cooling module (13). The gas is liquefied by the heat pump evaporator (201) to obtain high-pressure liquid and store it, thereby realizing energy storage.

12. The energy storage and release method according to claim 11, characterized in that: During the energy storage process: The third liquid circuit provides the cooling liquid required for cooling the compression cooling module (13), and simultaneously absorbs and stores the heat generated by compression of the compression cooling module (13); The first liquid circuit (50) provides the heat pump evaporator (201) with low-temperature liquid required for liquefaction and evaporates the low-temperature liquid into gas. At the same time, the evaporated gas completes a cycle of compression, cooling, liquefaction and evaporation in the first circuit.

13. The energy storage and release method according to claim 11, characterized in that: During the energy storage process: The second liquid circuit (60) absorbs and stores the heat generated during liquefaction in the first liquid circuit (50).

14. The energy storage and release method according to claim 11, characterized in that: Also included is an energy release method, the energy release method comprising: High-pressure liquid gas circulates in the expansion side passage (40) of the gas circulation loop, passes through the first heat exchanger (202) and the heating expansion module (44), the liquid gas is preheated by the first heat exchanger (202), and the liquid gas is heated and expanded by the heating expansion module (44) to obtain low-pressure gas, and returns to the compression side passage (10) through the connecting passage to achieve energy release.

15. The energy storage and release method according to claim 11, characterized in that: During the energy release process: The third liquid loop provides the heat required for the thermal expansion module to expand during heating; The second liquid loop (60) provides the heat required for preheating the third heat exchanger (204).

16. The energy storage and release method according to any one of claims 11 to 15, characterized in that: During the energy release process: The high-pressure liquid gas is preheated multiple times while circulating in the expansion side passage (40); The primary preheating is achieved by the second heat exchanger (203), and the heat required for heating the second heat exchanger (203) is provided by the third liquid path; The primary preheating is achieved by the third heat exchanger (204), and the heat required for heating the third heat exchanger (204) is provided by the second liquid circuit (60).

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