Carbon dioxide energy storage system, storage device thereof and working method of storage device

Abstract

The invention provides a carbon dioxide energy storage system, a storage device thereof and a working method of the storage device. Relates to the technical field of carbon dioxide energy storage. The storage device comprises a liquid storage container, a heat exchange module and a spraying structure. An inner cavity of the liquid storage container comprises a spraying area located on the upper portion and a liquid storage area located on the lower portion. The liquid storage container is provided with at least one gaseous carbon dioxide interface in the spraying area; the heat exchange module is located in the liquid storage area. An inlet and an outlet of the heat exchange module extend out of the liquid storage container; the heat exchange module is at least used for enabling a heat supply medium to flow in in an energy release stage to evaporate liquid carbon dioxide; the spraying structure comprises a spraying head; the spraying head is used for spraying liquid supercooled carbon dioxide to the spraying area in the energy storage stage, and the liquid supercooled carbon dioxide is liquid carbon dioxide with the temperature lower than the dew point of the gaseous carbon dioxide in the spraying area. The storage device can reduce the number of equipment and improve the condensation efficiency and the condensation conversion rate.

Description

Technical Field

[0001] The present disclosure relates to the technical field of carbon dioxide energy storage, and in particular to a carbon dioxide energy storage system and a storage device thereof, and a working method of the storage device. Background Art

[0002] The working process of the carbon dioxide gas-liquid phase change energy storage system includes the energy storage stage and the energy release stage. The specific operation method is to add a condenser on the energy storage side, complete the liquefaction process in the condenser, further cool the high-pressure gaseous carbon dioxide at the compressor outlet and condense it into liquid and store it in the liquid storage tank. On the energy release side, an evaporator is added at the outlet of the liquid storage tank, and the vaporization process is completed in the evaporator to make the carbon dioxide at the inlet of the expander reach a gas state.

[0003] In the related technology, the carbon dioxide gas-liquid phase change energy storage system needs to be equipped with a condenser, a liquid storage tank and an evaporator respectively, and the process pipelines of the liquefaction process and the vaporization process are long, the equipment foundation investment is large, the system process is complex, and the operation is difficult.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] The purpose of the present disclosure is to overcome the deficiencies of the above-mentioned prior art and to provide a carbon dioxide energy storage system and a storage device thereof, and a working method of the storage device, which can reduce the number of equipment and improve the condensation efficiency and condensation conversion rate.

[0006] According to one aspect of the present disclosure, a storage device of a carbon dioxide energy storage system is provided, comprising: A liquid storage container, wherein the internal cavity of the liquid storage container comprises a spraying area at the upper part and a liquid storage area at the lower part; the liquid storage container has at least one gaseous carbon dioxide interface in the spraying area; A heat exchange module is located in the liquid storage area; the inlet and outlet of the heat exchange module both extend outside the liquid storage container; the heat exchange module is at least used to flow in a heat supply medium to evaporate liquid carbon dioxide during the energy release stage; The spray structure comprises a spray head; the spray head is used to spray liquid supercooled carbon dioxide to the spray area during the energy storage stage, wherein the liquid supercooled carbon dioxide is liquid carbon dioxide having a temperature lower than the dew point of the gaseous carbon dioxide in the spray area.

[0007] In one embodiment of the present disclosure, the spray structure further includes a spray pipe, a spray liquid pump and a supercooler; The liquid storage area of ​​the liquid storage container is connected to the spray head through the spray pipe, the spray liquid pump and the supercooler are both arranged on the spray pipe, and the supercooler is configured to reduce the temperature of the liquid carbon dioxide flowing therethrough.

[0008] In one embodiment of the present disclosure, the heat exchange module is also used to flow a heat absorbing medium to cool the liquid carbon dioxide during the energy storage stage; The spray structure also includes a spray pipe and a spray liquid pump; The liquid storage area of ​​the liquid storage container is connected with the spray head through the spray pipe, and the spray liquid pump is arranged on the spray pipe.

[0009] In one embodiment of the present disclosure, the storage device further includes a fluid infusion tank; the fluid infusion tank is connected to the fluid storage container via a fluid infusion tube; The liquid replenishing tank is used to replenish liquid carbon dioxide to the liquid storage container.

[0010] In one embodiment of the present disclosure, the position of the fluid infusion tank is higher than the position of the fluid storage container, and the end of the fluid infusion tube connected to the fluid infusion tank is not lower than the end of the fluid infusion tube connected to the fluid storage container.

[0011] In one embodiment of the present disclosure, a driving pump is provided on the fluid infusion tube; The driving pump is at least configured to transfer at least a portion of the liquid carbon dioxide in the liquid storage container to the liquid replacement tank.

[0012] In one embodiment of the present disclosure, the storage device further includes an auxiliary liquid storage structure; The auxiliary liquid storage structure includes an auxiliary liquid storage tank; the inlet of the auxiliary liquid storage tank is connected to the liquid outlet of the liquid storage container through a first liquid storage tube, and the outlet of the auxiliary liquid storage tank is connected to the liquid inlet of the liquid storage container through a second liquid storage tube, and at least one of the first liquid storage tube and the second liquid storage tube is provided with a liquid storage pump.

[0013] In one embodiment of the present disclosure, the heat exchange module is a heat exchange tube.

[0014] According to another aspect provided by the present disclosure, a carbon dioxide energy storage system is provided, comprising the above storage device.

[0015] According to another aspect provided by the present disclosure, a working method of a storage device is provided, comprising: In the energy storage stage, liquid supercooled carbon dioxide is sprayed to condense gaseous carbon dioxide; During the energy release phase, a heat supply medium flows in to evaporate the liquid carbon dioxide.

[0016] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0018] Figure 1 This is a schematic diagram of a carbon dioxide energy storage system in one embodiment of the present disclosure.

[0019] Figure 2 This is a schematic diagram of a carbon dioxide energy storage system in one embodiment of the present disclosure.

[0020] Figure 3 This is a schematic diagram of a carbon dioxide energy storage system in one embodiment of the present disclosure.

[0021] Figure 4 This is a schematic diagram of a storage device in one embodiment of the present disclosure.

[0022] Figure 5 This is a schematic diagram of a storage device in one embodiment of the present disclosure.

[0023] Figure 6 This is a schematic diagram of a carbon dioxide energy storage system in one embodiment of the present disclosure.

[0024] Figure 7 This is a schematic diagram of a carbon dioxide energy storage system in one embodiment of the present disclosure.

[0025] Figure 8 This is a schematic diagram of a carbon dioxide energy storage system in one embodiment of the present disclosure.

[0026] Fig. 9 This is a schematic diagram of a carbon dioxide energy storage system in one embodiment of the present disclosure.

[0027] Fig.10 This is a schematic diagram of a carbon dioxide energy storage system in one embodiment of the present disclosure. DETAILED DESCRIPTION

[0028] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present disclosure will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their detailed description will be omitted. In addition, the drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale.

[0029] Although relative terms such as "upper" and "lower" are used in this specification to describe the relative relationship of one component of the illustration to another component, these terms are used in this specification only for convenience, such as according to the orientation of the examples described in the drawings. It is understood that if the device of the illustration is turned upside down, the component described as "upper" will become the component "lower". When a structure is "on" other structures, it may mean that the structure is formed integrally on the other structure, or that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure through another structure.

[0030] The terms "a", "an", "the", and "said" are used to indicate the presence of one element / component / etc.; the terms "including" and "having" are used to express an open-ended inclusion and mean that additional elements / components / etc. may exist in addition to the listed elements / components / etc.; the terms "first", "second", and "third", etc. are used merely as labels and are not intended to limit the quantity of their objects.

[0031] The present disclosure provides a carbon dioxide energy storage system. Figure 1The carbon dioxide energy storage system includes a gas storage device 100, and an energy storage component 200, a storage device 300 and an energy release component 400 connected in sequence. The gas storage device 100 is connected to the inlet of the energy storage component 200, the outlet of the energy storage component 200 is connected to the inlet of the storage device 300, the outlet of the storage device 300 is connected to the inlet of the energy release component 400, and the outlet of the energy release component 400 is connected to the gas storage device 100. The gas storage device 100 can store gaseous carbon dioxide, for example, low-temperature and low-pressure gaseous carbon dioxide; the storage device 300 can condense gaseous carbon dioxide, store and evaporate liquid carbon dioxide. The energy storage component 200 can use electricity to compress the gaseous carbon dioxide from the gas storage device 100 to achieve energy storage; the storage device 300 can cool the compressed gaseous carbon dioxide, for example, cool the compressed gaseous carbon dioxide to condense into liquid carbon dioxide and store it, or allow the cooled gaseous carbon dioxide to enter the storage device 300 to be condensed into liquid carbon dioxide and store it. The storage device 300 can also heat the stored liquid carbon dioxide, for example, by evaporating the liquid carbon dioxide stored in the storage device 300 into gaseous carbon dioxide and then sending it to the energy release component 400. The energy release component 400 heats the gaseous carbon dioxide and causes the heated gaseous carbon dioxide to expand and generate electricity.

[0032] For example, in the energy storage stage, the energy storage component 200 can compress the gaseous carbon dioxide from the gas storage device 100, and the storage device 300 can condense the compressed gaseous carbon dioxide, thereby causing the gaseous carbon dioxide to phase-change into liquid carbon dioxide and store it in the storage device 300. In the energy release stage, the storage device 300 can evaporate the liquid carbon dioxide stored therein into gaseous carbon dioxide, and the energy release component 400 can expand the gaseous carbon dioxide from the storage device 300 to generate electricity, thereby causing the gaseous carbon dioxide that has completed expansion and power generation to be stored in the gas storage device 100.

[0033] In one embodiment of the present disclosure, the gas storage device 100 may be a gas storage bin.

[0034] In one embodiment of the present disclosure, see Figure 2The energy storage assembly 200 includes at least one compressed energy storage unit 201; the compressed energy storage unit 201 includes a compressor 21 and an energy storage heat exchanger 22, and each compressed energy storage unit 201 is connected to the gas storage device 100 and the storage device 300. Specifically, the inlet of each compressed energy storage unit 201 is connected to the gas storage device 100, and the outlet of each compressed energy storage unit 201 is connected to the storage device 300. The compressor 21 can compress the gaseous carbon dioxide from the gas storage device 100 under electric drive, and compress the low-temperature and low-pressure gaseous carbon dioxide into high-temperature and high-pressure gaseous carbon dioxide. The compressed carbon dioxide can be heat exchanged and cooled in the energy storage heat exchanger 22, and the high-temperature and high-pressure gaseous carbon dioxide is formed into low-temperature and high-pressure gaseous carbon dioxide after heat exchange and cooling in the energy storage heat exchanger 22.

[0035] exist Figure 2 In the example, the energy storage assembly 200 includes three compressed energy storage parts 201. It is understood that in other embodiments of the present disclosure, the number of compressed energy storage parts 201 in the energy storage assembly 200 is not limited to 3, for example, it can be 1, or a plurality of other numbers (for example, 2, 4, 5 or 6).

[0036] In one embodiment of the present disclosure, the compressed energy storage unit 201 includes a compressed energy storage unit or a plurality of compressed energy storage units cascaded in sequence. A compressed energy storage unit may include a compressor 21 and an energy storage heat exchanger 22; the outlet of the compressor 21 is connected to the carbon dioxide inlet of the energy storage heat exchanger 22; in this way, after the gaseous carbon dioxide is compressed in the compressor 21, it flows into the energy storage heat exchanger 22 for heat exchange and cooling. When the compressed energy storage unit 201 includes a plurality of compressed energy storage units cascaded in sequence, between two adjacent compressed energy storage units, the carbon dioxide outlet of the energy storage heat exchanger 22 of the upper-stage compressed energy storage unit is connected to the inlet of the compressor 21 of the lower-stage compressed energy storage unit. Figure 2 In the example, the compressed energy storage part 201 includes two compressed energy storage units. It can be understood that, according to needs, the compressed energy storage unit in the compressed energy storage part 201 can be one, or two or more.

[0037] exist Figure 2 In the example, the solid arrows indicate the flow direction of the carbon dioxide in the compressed energy storage unit 201, and the dotted arrows indicate the flow direction of the cooling medium flowing through the energy storage heat exchanger 22. In the energy storage heat exchanger 22, the compressed carbon dioxide with a higher temperature exchanges heat with the cooling medium with a lower temperature, so that the carbon dioxide is cooled and thus facilitates condensation into liquid carbon dioxide, and the cooling medium absorbs heat and heats up to recover the heat generated during the compression of the carbon dioxide.

[0038] In one embodiment of the present disclosure, the inlet of the first-stage compressor 21 of the compressed energy storage unit 201 is connected to the gas storage device 100. It is understandable that when the compressed energy storage unit 201 has only one compressed energy storage unit, the inlet of the compressor 21 of the compressed energy storage unit 201 is connected to the gas storage device 100. Furthermore, a second valve 11 may be provided between the inlet of the first-stage compressor 21 and the gas storage device 100, and the second valve 11 is used to adjust and control the flow of gaseous carbon dioxide flowing therethrough. Figure 6~Figure 10 In the illustrated carbon dioxide energy storage system, only the first-stage compressor 21 of the compression energy storage unit 201 is shown, and each compressor 21 indicates that there is a corresponding compression energy storage unit 201 in the carbon dioxide energy storage system.

[0039] In one embodiment of the present disclosure, see Figure 3 The energy release assembly 400 includes at least one expansion energy release part 401; the expansion energy release part 401 includes a turbine 41 and an energy release heat exchanger 42, and each expansion energy release part 401 is connected to the gas storage device 100 and the storage device 300. Specifically, the inlet of each expansion energy release part 401 is connected to the storage device 300, and the outlet of each expansion energy release part 401 is connected to the gas storage device 100. The carbon dioxide from the storage device 300 can enter the turbine 41 after absorbing heat in the energy release heat exchanger 42, and then drive the generator G to generate electricity.

[0040] exist Figure 3 In the example, the energy release component 400 includes three expansion energy release parts 401. It is understandable that in other embodiments of the present disclosure, the number of expansion energy release parts 401 in the energy release component 400 is not limited to 3, for example, it can be 1, or other numbers (for example, 2, 4, 5 or 6).

[0041] In one embodiment of the present disclosure, the expansion energy release section 401 includes one expansion energy release unit or multiple expansion energy release units cascaded in sequence. One expansion energy release unit may include a turbine 41 and an energy release heat exchanger 42; the carbon dioxide outlet of the energy release heat exchanger 42 is connected to the inlet of the turbine 41; in this way, after carbon dioxide absorbs heat in the energy release heat exchanger 42, it flows into the turbine 41 to expand and generate electricity. When the expansion energy release section 401 includes multiple expansion energy release units cascaded in sequence, between two adjacent expansion energy release units, the outlet of the turbine 41 of the upper-stage expansion energy release unit is connected to the carbon dioxide inlet of the energy release heat exchanger 42 of the lower-stage expansion energy release unit. Figure 3 In the example of , the expansion energy release part 401 includes two expansion energy release units. It can be understood that, according to needs, the expansion energy release unit in the expansion energy release part 401 can be one, or two or more.

[0042] exist Figure 3In the example, the solid arrows indicate the flow direction of the carbon dioxide in the expansion energy release part 401, and the dotted arrows indicate the flow direction of the heating medium flowing through the energy release heat exchanger 42. In the energy release heat exchanger 42, the carbon dioxide that flows out of the storage device 300 and expands and cools down exchanges heat with the heating medium with a higher temperature, thereby heating the carbon dioxide, which can recover the cold energy generated by the expansion of the gaseous carbon dioxide.

[0043] In one embodiment of the present disclosure, the outlet of the last stage turbine 41 of the expansion energy release section 401 is connected to the gas storage device 100. It is understandable that when the expansion energy release section 401 has only one expansion energy release unit, the outlet of the turbine 41 of the expansion energy release section 401 is connected to the gas storage device 100. Optionally, a sixth valve 15 is provided between the outlet of the last stage turbine 41 of the expansion energy release section 401 and the gas storage device 100, wherein the sixth valve 15 serves as a switch valve, which is closed in the energy storage stage and opened in the energy release stage. Figure 6~Figure 10 In the illustrated carbon dioxide energy storage system, only the last stage turbine 41 of the expansion energy release part 401 is shown, and each turbine 41 indicates the existence of a corresponding expansion energy release part 401 .

[0044] It is understood that in other embodiments of the present disclosure, the carbon dioxide energy storage system may be further provided with other components. In one example, the carbon dioxide energy storage system may also be provided with a heat recovery component, which includes a heat storage tank 24 and a cold storage tank 23. In the energy storage stage, the energy storage heat exchanger 22 may exchange heat with the low-temperature medium from the cold storage tank 23 (i.e., the cooling medium flowing into the energy storage heat exchanger 22), so that the carbon dioxide in the energy storage heat exchanger 22 is cooled down, and the low-temperature medium is heated to a high-temperature medium and then stored in the heat storage tank 24. In the energy release stage, the energy release heat exchanger 42 may exchange heat with the high-temperature medium from the heat storage tank 24 (i.e., the heating medium flowing into the energy release heat exchanger 42), so that the carbon dioxide in the energy release heat exchanger 42 is heated up, and the high-temperature medium is cooled down to a low-temperature medium and then stored in the cold storage tank 23. In this example, the heating medium and the cooling medium are heat exchange media circulating between the heat storage tank 24 and the cold storage tank 23, and the temperature states of the two are different.

[0045] In one embodiment of the present disclosure, the compression energy storage part 201 includes a compression energy storage unit, and the expansion energy release part 401 includes an expansion energy release unit. Figure 6-Figure 10 The inlet of the compressor 21 is connected to the outlet of the gas storage device 100 through the third pipeline 8, the inlet of the energy storage heat exchanger 22 is connected to the outlet of the compressor 21 through the fourth pipeline 9, and the outlet of the energy storage heat exchanger 22 is connected to the storage device 300 through the fifth pipeline 20. In this example, the second valve 11 is arranged on the third pipeline 8.

[0046] In one embodiment of the present disclosure, see Figure 6-Figure 10 The energy storage heat exchanger 22 has a gaseous carbon dioxide outlet and a gaseous carbon dioxide inlet, the outlet of the compressor 21 is connected to the gaseous carbon dioxide inlet of the energy storage heat exchanger 22 through the fourth pipeline 9, and the gaseous carbon dioxide outlet of the energy storage heat exchanger 22 is connected to the storage device 300 through the fifth pipeline 20. The energy storage heat exchanger 22 also has a first medium inlet and a first medium outlet, the cold storage tank 23 is connected to the first medium inlet through the first pipeline 6, and the first medium outlet is connected to the heat storage tank 24 through the second pipeline 7. The first circulation pump 25 is arranged on the first pipeline 6, and the first valve 10 is arranged between the first circulation pump 25 and the first medium inlet. In this example, the heat storage tank 24 is used to store high-temperature medium after absorbing the heat of gaseous carbon dioxide, the cold storage tank 23 is used to store low-temperature medium after releasing the heat of carbon dioxide, and the first circulation pump 25 is used to transport the low-temperature medium to the energy storage heat exchanger 22; the first valve 10 is used to adjust and control the flow of the low-temperature medium in the cold storage tank 23 entering the energy storage heat exchanger 22.

[0047] In one embodiment of the present disclosure, the low temperature medium and the high temperature medium may be water, heat transfer oil, molten salt, etc. Of course, in other examples, the low temperature medium and the high temperature medium may also be other components not shown.

[0048] In one embodiment of the present disclosure, the inlet of the energy-releasing heat exchanger 42 is connected to the storage device 300 through the sixth pipeline 1. The outlet of the energy-releasing heat exchanger 42 is connected to the inlet of the turbine 41 through the seventh pipeline 2. The turbine 41 is equipped with a generator G, which is used to convert the mechanical energy of the high-temperature and high-pressure gaseous carbon dioxide expanding in the turbine 41 into electrical energy. The outlet of the turbine 41 is connected to the inlet of the gas storage device 100 through the eighth pipeline 3, and the sixth valve 15 is arranged on the eighth pipeline 3.

[0049] In one embodiment of the present disclosure, the turbine 41 is used to expand the high-temperature and high-pressure gaseous carbon dioxide to convert it into low-temperature and low-pressure gaseous carbon dioxide, and the generator G is used to convert the mechanical energy of the high-temperature and high-pressure gaseous carbon dioxide expanding in the turbine into electrical energy.

[0050] In one embodiment of the present disclosure, see Figure 6-Figure 10The energy-releasing heat exchanger 42 has a gaseous carbon dioxide outlet and a gaseous carbon dioxide inlet. The outlet of the storage device 300 is connected to the gaseous carbon dioxide inlet of the energy-releasing heat exchanger 42 through the sixth pipeline 1, and the gaseous carbon dioxide outlet of the energy-releasing heat exchanger 42 is connected to the turbine 41 through the seventh pipeline 2. The energy-releasing heat exchanger 42 also has a second medium inlet and a second medium outlet. The heat storage tank 24 is connected to the second medium inlet through the ninth pipeline 4, and the second medium outlet is connected to the cold storage tank 23 through the tenth pipeline 5. The second circulation pump 13 is provided on the ninth pipeline 4, and the fourth valve 14 is provided between the second circulation pump 13 and the second medium inlet. In this example, the second circulation pump 13 is used to transport high-temperature medium to the energy-releasing heat exchanger 42; the fourth valve 14 is used to adjust and control the flow of the high-temperature medium in the heat storage tank 24 into the energy-releasing heat exchanger 42; the energy-releasing heat exchanger 42 is used to transfer the heat of the high-temperature medium in the heat storage tank 24 to the low-temperature and high-pressure gaseous carbon dioxide, so that it becomes high-temperature and high-pressure gaseous carbon dioxide; after the high-temperature medium releases heat, the temperature decreases to form a low-temperature medium stored in the cold storage tank 23. In the present disclosure, the same group of cold storage tanks 23 and heat storage tanks 24 are used to realize the recycling of heat between the energy storage heat exchanger 22 and the energy-releasing heat exchanger 42, which not only improves energy utilization, but also reduces the number of equipment, simplifies the process and operation method, and reduces costs.

[0051] exist Figure 1 to Figure 10 In the example, the number of storage devices 300 is one. It is understandable that in the embodiment of the present disclosure, the number of storage devices 300 may also be multiple. When the number of storage devices 300 is multiple, these storage devices 300 may be connected in series, or in parallel, or may be connected in a mixed manner of series and parallel.

[0052] In the related art, the storage device includes a condenser, a liquid storage container and an evaporator, and the condenser is arranged between the last stage compression energy storage unit and the liquid storage container. In other words, the carbon dioxide outlet of the last stage energy storage heat exchanger can be connected to the carbon dioxide inlet of the condenser, and the carbon dioxide outlet of the condenser can be connected to the inlet of the liquid storage container. The condenser can condense the gaseous carbon dioxide from the compression energy storage unit so that the low-temperature and high-pressure gaseous carbon dioxide from the compression energy storage unit is condensed into low-temperature and high-pressure liquid carbon dioxide and stored in the liquid storage container. The evaporator is arranged between the first stage expansion energy release unit and the liquid storage container. In other words, the carbon dioxide inlet of the first stage energy release heat exchanger can be connected to the carbon dioxide outlet of the evaporator, and the carbon dioxide inlet of the evaporator can be connected to the outlet of the liquid storage container. The evaporator can heat the low-temperature and high-pressure liquid carbon dioxide from the liquid storage container, so that the low-temperature and high-pressure liquid carbon dioxide from the liquid storage container evaporates into low-temperature and high-pressure gaseous carbon dioxide and flows into the energy release heat exchanger.

[0053] In the related art, the condenser, liquid storage container and evaporator in the storage device are independently arranged, which makes the process pipelines of the liquefaction process and the vaporization process longer, the equipment foundation investment larger, the system process complex and the operation difficult.

[0054] To solve the above problems, see Figure 4-Figure 10 The present disclosure provides a storage device 300. The storage device 300 realizes the integration of condensation, storage and evaporation, reduces the process pipelines of the liquefaction process and the vaporization process, reduces the cost and is simple to operate.

[0055] In one example, see Figure 4-Figure 10 The storage device 300 includes a liquid storage container 31, a heat exchange module 32 and a spray structure.

[0056] In this example, see Figure 4-Figure 10 The liquid storage container 31 has a cavity, the interior of the cavity is used to provide space for the condensation phase change and evaporation phase change of carbon dioxide, as well as for providing space for storing liquid carbon dioxide, and for providing space for setting the heat exchange module 32 and setting the spray structure. The cavity is divided into a spray area RP and a liquid storage area RC from top to bottom (in other words, the cavity includes a spray area RP located at the upper part and a liquid storage area RC located at the lower part), and at least one gaseous carbon dioxide interface VO is provided on the liquid storage container 31. In one example, the spray area RP and the liquid storage area RC can be dynamically adjusted based on the stock of liquid carbon dioxide in the liquid storage container 31.

[0057] In one example of the present disclosure, see Figure 4 , a gaseous carbon dioxide interface VO is provided on the liquid storage container 31. At this time, the gaseous carbon dioxide interface VO serves as both a gaseous carbon dioxide outlet and a gaseous carbon dioxide inlet, and a T-shaped pipe is connected to the gaseous carbon dioxide interface VO. In one example, see Figure 4 , the first end of the T-shaped pipe is connected to the gaseous carbon dioxide interface VO, the second end of the T-shaped pipe is used to connect the fifth pipe 20, the third end of the T-shaped pipe is used to connect the sixth pipe 1, and the second end of the T-shaped pipe is provided with a third valve 12, and the third valve 12 is used as a switch valve, which is configured to open in the energy storage stage and close in the energy release stage. The third end of the T-shaped pipe is provided with a fifth valve 16, wherein the fifth valve 16 is used to adjust and control the flow rate of the gaseous carbon dioxide outlet in the storage device 300. In another example, the T-shaped pipe can be formed by connecting three pipes through a three-way valve. The third valve 12 and the fifth valve 16 can control the flow direction of the gaseous carbon dioxide (for example, when the third valve 12 is closed and the fifth valve 16 is opened, the gaseous carbon dioxide flows out from the sixth pipe 1, and vice versa, when the third valve 12 is opened and the fifth valve 16 is closed, the gaseous carbon dioxide flows from the fifth pipe 20 into the liquid storage container 31).

[0058] In another example of the present disclosure, see Figure 5-Figure 10 , two gaseous carbon dioxide interfaces VO are provided on the liquid storage container 31, one of which is a gaseous carbon dioxide outlet, and the other is a gaseous carbon dioxide inlet. The gaseous carbon dioxide outlet is connected to an outlet pipe 17, and a fifth valve 16 is provided on the outlet pipe 17, and the gaseous carbon dioxide inlet is connected to an inlet pipe 18, and a third valve 12 is provided on the inlet pipe 18. In this example, the fifth pipe 20 is connected to the inlet pipe 18, and the sixth pipe 1 is connected to the outlet pipe 17. In one example, the gaseous carbon dioxide inlet and the gaseous carbon dioxide outlet can be located at the same height of the liquid storage container 31. In other examples, the gaseous carbon dioxide inlet and the gaseous carbon dioxide outlet can be staggered along the vertical direction of the liquid storage container 31 (that is, the gaseous carbon dioxide inlet and the gaseous carbon dioxide outlet are not at the same height). For example, the height of the gaseous carbon dioxide inlet on the liquid storage container 31 is higher than the height of the gaseous carbon dioxide outlet on the liquid storage container 31.

[0059] In one embodiment of the present disclosure, the gaseous carbon dioxide interface VO on the liquid storage container 31 can be located in the spraying area RP. In this way, the time for the gaseous carbon dioxide to directly mix and contact with the liquid supercooled carbon dioxide can be extended, so that the gaseous carbon dioxide and the liquid supercooled carbon dioxide can be fully contacted, thereby improving the condensation efficiency of the gaseous carbon dioxide. In one example, the gaseous carbon dioxide inlet is higher than the gaseous carbon dioxide outlet, which can also extend the contact time between the low-temperature and high-pressure gaseous carbon dioxide entering the liquid storage container 31 and the liquid supercooled carbon dioxide, thereby improving the condensation efficiency of the gaseous carbon dioxide.

[0060] In one embodiment of the present disclosure, see Figure 4-Figure 10 , a heat exchange medium flows in the heat exchange module 32 for heat exchange with carbon dioxide, thereby causing the carbon dioxide to change phase. In this example, the heat exchange module 32 is arranged in the cavity and located in the liquid storage area RC, and the inlet and outlet of the heat exchange module 32 both extend outside the liquid storage container 31. It can be understood that the heat exchange module 32 has a first end and a second end, wherein the first end can be used as the inlet of the heat exchange module 32, and the second end can be used as the outlet of the heat exchange module 32, and the inlet and outlet of the heat exchange module 32 pass through the liquid storage container 31 and are placed outside the liquid storage container 31.

[0061] In one embodiment of the present disclosure, the heat exchange module 32 may be a heat exchange tube. In other examples, the heat exchange module 32 may be a heat exchange plate. Of course, it is understood that the heat exchange module 32 may also be other structures not shown.

[0062] In one embodiment of the present disclosure, a plurality of heat exchange teeth may be provided on the circumference of the heat exchange module 32, so that the heat transfer may be accelerated.

[0063] In one embodiment of the present disclosure, the number of heat exchange modules 32 may be one. In other embodiments, the number of heat exchange modules 32 may be multiple, so that the phase change conversion efficiency of carbon dioxide can be accelerated by increasing the contact area between carbon dioxide and the heat exchange module 32; and the phase change conversion efficiency of carbon dioxide can be accelerated by increasing the total flow rate of the heat exchange medium entering the liquid storage area RC.

[0064] In one embodiment of the present disclosure, taking the heat exchange module 32 as an example of a heat exchange tube, the heat exchange tube can be arranged in sequence along the first direction, so that the contact area between the carbon dioxide and the heat exchange tube can be increased, and the conversion efficiency of the carbon dioxide can be accelerated. In another embodiment, the heat exchange tube can be arranged in sequence along the second direction, so that the contact area between the carbon dioxide and the heat exchange tube can be increased, and the conversion efficiency of the carbon dioxide can be accelerated. In another embodiment, the heat exchange tube can be arranged in the first direction and the second direction at the same time, so that the heat exchange tube forms a multi-layer structure, which can further increase the contact area between the carbon dioxide and the heat exchange tube and accelerate the conversion efficiency of the carbon dioxide. Among them, the first direction intersects with the second direction. In one example, the second direction refers to the arrangement direction of the spray area RP and the liquid storage area RC, and the first direction is perpendicular to the second direction.

[0065] In this example, the inlet and outlet of the heat exchange module 32 are used to connect to a medium conveying device, which can allow the heat exchange medium to flow in through the inlet of the heat exchange module 32 and out through the outlet, so that the liquid carbon dioxide in the liquid storage area RC can transfer heat with the heat exchange medium, thereby realizing the function of evaporating the liquid carbon dioxide into gaseous carbon dioxide.

[0066] In one embodiment of the present disclosure, see Figure 6-Figure 10 The spray structure includes a spray pipe 33, a spray liquid pump 34 and a spray head 35; wherein, the first end of the spray pipe 33 is connected to the liquid storage area RC of the liquid storage container 31 (in other words, the liquid storage container 31 has a liquid carbon dioxide spray outlet in the liquid storage area RC, and the liquid carbon dioxide spray outlet is located at the bottom of the liquid storage container 31, and the first end of the spray pipe 33 is connected to the liquid carbon dioxide spray outlet), the second end of the spray pipe 33 is connected to the inlet of the spray head 35 (in this example, the first end of the spray pipe 33 serves as the inlet of the spray pipe 33, and the second end of the spray pipe 33 serves as the outlet of the spray pipe 33), the spraying end of the spray head 35 is located in the spray area RP inside the liquid storage container 31, and the spray liquid pump 34 is arranged on the spray pipe 33.

[0067] In the first embodiment of the present disclosure, see Figure 6In the energy release stage, the heat exchange medium is a heat supply medium. In other words, the heat exchange module 32 is used to flow into the heat supply medium in the energy release stage to evaporate the liquid carbon dioxide. In the energy storage stage, the heat exchange medium is a heat absorption medium. In other words, the heat exchange module 32 is used to flow into the heat absorption medium in the energy release stage to condense the gaseous carbon dioxide, so that the gaseous carbon dioxide changes into liquid supercooled carbon dioxide. It can be understood that the heat exchange module 32 can not only condense the gaseous carbon dioxide into liquid carbon dioxide, but also further convert the liquid carbon dioxide into liquid supercooled carbon dioxide in the energy storage stage.

[0068] In this example, when in the energy storage stage, a heat absorbing medium is injected into the heat exchange module 32, and the low-temperature and high-pressure gaseous carbon dioxide entering the liquid storage container 31 is condensed and phase-changed into liquid carbon dioxide under the action of the heat absorbing medium. The liquid carbon dioxide is transformed into liquid supercooled carbon dioxide in the continuous heat exchange with the heat absorbing medium. The spray liquid pump 34 of the spray structure extracts the liquid supercooled carbon dioxide and sprays it in the spray area RP through the spray head 35. The liquid supercooled carbon dioxide is directly contacted and mixed with the low-temperature and high-pressure gaseous carbon dioxide that continuously enters the liquid storage container 31, so as to achieve a rapid phase change from gaseous carbon dioxide to liquid carbon dioxide, that is, to complete the condensation process of carbon dioxide (it can be understood that the condensation process of carbon dioxide is that the liquid supercooled carbon dioxide sprayed by the spray structure is in direct contact with the gaseous carbon dioxide at the gaseous carbon dioxide inlet in the cavity of the liquid storage container 31, so that the gaseous carbon dioxide is condensed into liquid carbon dioxide and stored in the liquid storage area RC of the liquid storage container 31). The condensation efficiency of this condensation method is much higher than that of the existing partition wall condensation process. Alternatively, under the premise that there is liquid carbon dioxide in the liquid storage container 31, the liquid carbon dioxide is directly converted into liquid supercooled carbon dioxide during heat exchange with the heat absorbing medium. The spray structure extracts the liquid supercooled carbon dioxide and sprays it in the spray area RP, where it directly contacts and mixes with the low-temperature and high-pressure gaseous carbon dioxide entering the liquid storage container 31, thereby realizing the rapid conversion of gaseous carbon dioxide into liquid carbon dioxide, that is, completing the condensation process of carbon dioxide.

[0069] In this embodiment, the present disclosure provides a method for using a carbon dioxide energy storage system, comprising: In the first working mode (energy storage stage): The second valve 11, the first valve 10, the third valve 12 and the seventh valve 19 are opened, and the fifth valve 16, the fourth valve 14 and the sixth valve 15 are closed; the low-temperature and low-pressure gaseous carbon dioxide in the gas storage device 100 is compressed by the compressor 21, and becomes high-temperature and high-pressure gaseous carbon dioxide and then enters the energy storage heat exchanger 22, and the energy storage heat exchanger 22 exchanges heat with the low-temperature medium in the cold storage tank 23, and transfers the heat of the high-temperature and high-pressure gaseous carbon dioxide in the energy storage heat exchanger 22 to the low-temperature medium, so that the high-temperature and high-pressure gaseous carbon dioxide is converted into low-temperature and high-pressure gaseous carbon dioxide, and the low-temperature medium in the cold storage tank 23 is converted into a high-temperature medium and stored in the heat storage tank 24, and the low-temperature and high-pressure gaseous carbon dioxide enters the liquid storage container 31, and the heat absorbing medium is introduced into the heat exchange module 32. The heat absorbing medium exchanges heat with the liquid carbon dioxide in the liquid storage container 31, so that the liquid carbon dioxide forms liquid supercooled carbon dioxide (or, the heat absorbing medium exchanges heat with the gaseous carbon dioxide entering the liquid storage container 31, so that the gaseous carbon dioxide condenses and changes into liquid carbon dioxide, and the liquid carbon dioxide continues to exchange heat with the heat absorbing medium, so that the liquid carbon dioxide forms liquid supercooled carbon dioxide), the spray liquid pump 34 extracts the liquid supercooled carbon dioxide in the liquid storage container 31, and sprays it in the spray area RP of the liquid storage container 31 through the spray head 35, and the gaseous carbon dioxide entering the liquid storage container 31 directly mixes and contacts with the liquid supercooled carbon dioxide, so that the low-temperature and high-pressure gaseous carbon dioxide is condensed into low-temperature and high-pressure liquid carbon dioxide and stored in the liquid storage container 31. During the power off-peak period, the carbon dioxide energy storage system can be operated according to the first working mode, using the surplus power to drive the compressed gaseous carbon dioxide, condense it into liquid carbon dioxide and store it, and store the heat energy generated during the compression process.

[0070] In the second working mode (energy release stage): The fifth valve 16, the fourth valve 14, and the sixth valve 15 are opened, and the second valve 11, the first valve 10, the third valve 12, and the seventh valve 19 are closed, and the heat supply medium is injected into the heat exchange module 32. The low-temperature and high-pressure liquid carbon dioxide stored in the liquid storage container 31 exchanges heat with the heat supply medium in the heat exchange module 32, and the heat of the heat supply medium in the heat exchange module 32 is transferred to the low-temperature and high-pressure liquid carbon dioxide, completing the evaporation process of the liquid carbon dioxide, and becomes low-temperature and high-pressure gaseous carbon dioxide and enters the energy release heat exchanger 42, exchanges heat with the high-temperature medium in the heat storage tank 24, and transfers the heat of the high-temperature medium to the low-temperature and high-pressure gaseous carbon dioxide, so that the high-temperature medium in the heat storage tank 24 becomes a low-temperature medium and is stored in the cold storage tank 23, and the low-temperature and high-pressure gaseous carbon dioxide absorbs heat to become high-temperature and high-pressure gaseous carbon dioxide and enters the turbine 41 to expand and work, and the generator G converts the mechanical energy of the expansion work of the turbine 41 into electrical energy, and the low-temperature and low-pressure gaseous carbon dioxide after expansion and work returns to the gas storage device 100 for storage, completing the energy release stage. This mode is used to operate during peak electricity consumption periods, using low-grade heat to vaporize liquid carbon dioxide, and promoting the expansion of gaseous carbon dioxide through the heat energy stored in the first working mode, driving the turbine 41 to generate electricity, and storing the expanded low-temperature and low-pressure gaseous carbon dioxide in the gas storage device 100 for the next cycle.

[0071] In the present disclosure, by setting up a storage device 300 that integrates condensation, storage and evaporation, the liquid supercooled carbon dioxide is sprayed by the spray structure to directly contact and mix with the gaseous carbon dioxide entering the liquid storage container 31, so that the gaseous carbon dioxide is condensed and phase-changed into liquid carbon dioxide (liquid supercooled carbon dioxide), and the cycle of carbon dioxide phase change is realized (the liquid carbon dioxide formed by the condensation of gaseous carbon dioxide can be used for the condensation of gaseous carbon dioxide after being supercooled to form liquid supercooled carbon dioxide), and the heat supply medium circulating in the heat exchange module 32 is used to make the liquid carbon dioxide (liquid supercooled carbon dioxide) phase-changed into gaseous carbon dioxide, realizing the integration of condensation, storage and evaporation functions, which can reduce the number of equipment in the carbon dioxide energy storage system and the amount of pipeline design and construction. In addition, since the number of equipment in the carbon dioxide energy storage system is reduced (for example, the number of liquid pumps is reduced), the loss of pressure energy is reduced, the energy consumption of the carbon dioxide energy storage system is reduced, the equipment investment of the carbon dioxide energy storage system is reduced, the risk of equipment corrosion is reduced, the repair and maintenance cost is reduced, and the operation process is optimized.

[0072] The present disclosure provides a new method for the condensation phase change of gaseous carbon dioxide (using a condensation process in which liquid supercooled carbon dioxide is in direct contact with gaseous carbon dioxide to complete the condensation of gaseous carbon dioxide), and has a higher heat transfer efficiency and can condense more quickly. Under the same heat load, the required internal components of the equipment are simpler, which can significantly reduce equipment investment. Compared with the partition wall condensation in the related art, this high-efficiency mixed condensation method can significantly improve the heat transfer coefficient and make the condensation process faster and more efficient. In addition, the present disclosure optimizes the operating procedures of the carbon dioxide energy storage system during operation, which can improve the reliability of the operation of the carbon dioxide energy storage system, as well as improve the efficiency and energy utilization of the energy storage system; it can also reduce the floor space occupied by the equipment, reduce the equipment cost of the entire energy storage system, and facilitate the promotion and use of the gas-liquid phase change carbon dioxide energy storage system.

[0073] In the second embodiment of the present disclosure, see Figure 8 , the heat exchange medium is the heat supply medium. In other words, the heat exchange module 32 is only used to allow the heat supply medium to flow into the energy release stage to evaporate the liquid carbon dioxide.

[0074] In this example, the spray structure also includes a subcooler 44. The subcooler 44 is arranged on the spray pipe 33, and the subcooler 44 is located between the spray liquid pump 34 and the liquid outlet of the liquid storage container 31. The subcooler 44 is configured to reduce the temperature of the liquid carbon dioxide flowing through it. In other words, the subcooler 44 is configured to convert the liquid carbon dioxide flowing through it into liquid subcooled carbon dioxide. The spray liquid pump 34 is configured to deliver liquid subcooled carbon dioxide to the inlet of the spray head 35 through the spray pipe 33 (of course, in other examples, the subcooler 44 can also be located between the spray liquid pump 34 and the spray head 35, and the spray liquid pump 34 is configured to deliver liquid carbon dioxide to the inlet of the spray head 35 through the spray pipe 33, and then subcool the liquid carbon dioxide through the subcooler 44). The spray pipe 33 is provided with a seventh valve 19 between the spray liquid pump 34 and the subcooler 44, and the seventh valve 19 is used to adjust and control the flow of carbon dioxide flowing through it. The liquid supercooled carbon dioxide is liquid carbon dioxide having a temperature lower than the dew point of the gaseous carbon dioxide in the spraying area RP.

[0075] In this embodiment, the present disclosure provides a method for using a carbon dioxide energy storage system, comprising: In the first working mode (energy storage stage): The second valve 11, the first valve 10, the third valve 12 and the seventh valve 19 are opened, and the fifth valve 16, the fourth valve 14 and the sixth valve 15 are closed; the low-temperature and low-pressure gaseous carbon dioxide in the gas storage device 100 is compressed by the compressor 21, and becomes high-temperature and high-pressure gaseous carbon dioxide and then enters the energy storage heat exchanger 22. In the energy storage heat exchanger 22, the high-temperature and high-pressure gaseous carbon dioxide exchanges heat with the low-temperature medium in the cold storage tank 23, and the heat of the high-temperature and high-pressure gaseous carbon dioxide in the energy storage heat exchanger 22 is transferred to the low-temperature medium, so that the low-temperature medium in the cold storage tank 23 becomes a high-temperature medium and is stored in the heat storage tank 24. The high-temperature and high-pressure gaseous carbon dioxide is converted into low-temperature and high-pressure gaseous carbon dioxide and enters the liquid storage container 31. The spray liquid pump 34 extracts the liquid carbon dioxide in the liquid storage container 31 (the liquid carbon dioxide in the liquid storage container 31 may be the liquid carbon dioxide previously stored in the liquid storage container 31). After the liquid carbon dioxide is supercooled by the supercooler 44, it is sprayed in the spray area RP of the liquid storage container 31 by the spray head 35. The gaseous carbon dioxide entering the liquid storage container 31 is directly mixed and contacted with the liquid supercooled carbon dioxide, so that the low-temperature and high-pressure gaseous carbon dioxide is condensed into low-temperature and high-pressure liquid carbon dioxide and stored in the liquid storage container 31.

[0076] In the second working mode (energy release stage): The fifth valve 16, the fourth valve 14, and the sixth valve 15 are opened, and the second valve 11, the first valve 10, the third valve 12, and the seventh valve 19 are closed, and the heat supply medium is injected into the heat exchange module 32. The low-temperature and high-pressure liquid carbon dioxide stored in the liquid storage container 31 exchanges heat with the heat supply medium in the heat exchange module 32, and the heat of the heat supply medium in the heat exchange module 32 is transferred to the low-temperature and high-pressure liquid carbon dioxide, completing the evaporation process of the liquid carbon dioxide, and becomes low-temperature and high-pressure gaseous carbon dioxide and enters the energy release heat exchanger 42, exchanges heat with the high-temperature medium in the heat storage tank 24, and transfers the heat of the high-temperature medium to the low-temperature and high-pressure gaseous carbon dioxide, so that the high-temperature medium in the heat storage tank 24 becomes a low-temperature medium and is stored in the cold storage tank 23, and the low-temperature and high-pressure gaseous carbon dioxide absorbs heat to become high-temperature and high-pressure gaseous carbon dioxide and enters the turbine 41 to expand and work, and the generator G converts the mechanical energy of the expansion work of the turbine 41 into electrical energy, and the low-temperature and low-pressure gaseous carbon dioxide after expansion and work returns to the gas storage device 100 for storage, completing the energy release stage.

[0077] In the present disclosure, by setting up an integrated storage device 300, the liquid supercooled carbon dioxide is sprayed by the spray structure to directly contact and mix with the gaseous carbon dioxide entering the liquid storage container 31, so as to realize the condensation phase change of the gaseous carbon dioxide into liquid carbon dioxide (liquid supercooled carbon dioxide), and realize the cycle of carbon dioxide phase change (the spray head 35 sprays the liquid supercooled carbon dioxide in the spray area RP), and the liquid carbon dioxide (liquid supercooled carbon dioxide) is transformed into gaseous carbon dioxide by the heat supply medium circulating in the heat exchange module 32, realizing the integration of condensation, storage and evaporation functions, which can reduce the number of equipment and pipeline design and construction in the carbon dioxide energy storage system. Since the number of equipment in the energy storage system is reduced (for example, the number of liquid pumps is reduced), the loss of pressure energy is reduced, the energy consumption of the carbon dioxide energy storage system is reduced, the equipment investment of the carbon dioxide energy storage system is reduced, the risk of equipment corrosion is reduced, the repair and maintenance cost is reduced, and the operation process is optimized.

[0078] The present disclosure provides a new method for the condensation phase change of gaseous carbon dioxide (using a condensation process in which liquid supercooled carbon dioxide is in direct contact with gaseous carbon dioxide to complete the condensation of gaseous carbon dioxide), and has a higher heat transfer efficiency and can condense more quickly. Under the same heat load, the required internal components of the equipment are simpler, which can significantly reduce equipment investment. Compared with the partition wall condensation in the related art, this high-efficiency mixed condensation method can significantly improve the heat transfer coefficient and make the condensation process faster and more efficient. In addition, the present disclosure optimizes the operating procedures of the carbon dioxide energy storage system during operation, which can improve the reliability of the operation of the carbon dioxide energy storage system, as well as improve the efficiency and energy utilization of the energy storage system; it can also reduce the floor space occupied by the equipment, reduce the equipment cost of the entire energy storage system, and facilitate the promotion and use of the gas-liquid phase change carbon dioxide energy storage system.

[0079] In the third embodiment of the present disclosure, see Fig.10 In the energy release stage, the heat exchange medium is a heat supply medium. In other words, the heat exchange module 32 is used to flow into the heat supply medium in the energy release stage to evaporate the liquid carbon dioxide. In the energy storage stage, the heat exchange medium is a heat absorption medium. In other words, the heat exchange module 32 is used to flow into the heat absorption medium in the energy release stage to condense the gaseous carbon dioxide, so that the gaseous carbon dioxide changes into liquid supercooled carbon dioxide. It can be understood that the heat exchange module 32 can not only condense the gaseous carbon dioxide into liquid supercooled carbon dioxide, but also further convert the liquid carbon dioxide into liquid supercooled carbon dioxide in the energy storage stage.

[0080] In this example, the spray structure also includes a subcooler 44. The subcooler 44 is arranged on the spray pipe 33, and the subcooler 44 is located between the spray liquid pump 34 and the liquid outlet of the liquid storage container 31 (of course, in other examples, the subcooler 44 can also be located between the spray liquid pump 34 and the spray head 35), and the subcooler 44 is configured to further reduce the temperature of the liquid subcooled carbon dioxide flowing through it. In other words, the subcooler 44 is configured to subcool the liquid subcooled carbon dioxide that further flows through it. The spray liquid pump 34 is configured to deliver liquid subcooled carbon dioxide to the inlet of the spray head 35 through the spray pipe 33. The spray pipe 33 is provided with a seventh valve 19 between the spray liquid pump 34 and the subcooler 44, and the seventh valve 19 is used to adjust and control the flow rate of the liquid subcooled carbon dioxide flowing through it. Among them, the liquid subcooled carbon dioxide is liquid carbon dioxide whose temperature is lower than the dew point of the gaseous carbon dioxide in the spray area RP.

[0081] In this embodiment, during the energy storage stage of the carbon dioxide energy storage system in the present disclosure, the liquid supercooled carbon dioxide flowing through the spray pipe 33 is subjected to secondary supercooling by the supercooler, thereby further reducing the temperature of the liquid supercooled carbon dioxide and further improving the condensation efficiency.

[0082] In this embodiment, in the method for using the carbon dioxide energy storage system in the present disclosure, the process of the energy storage stage is as follows: The second valve 11, the first valve 10, the third valve 12 and the seventh valve 19 are opened, and the fifth valve 16, the fourth valve 14 and the sixth valve 15 are closed; the low-temperature and low-pressure gaseous carbon dioxide in the gas storage device 100 is compressed by the compressor 21, and becomes high-temperature and high-pressure gaseous carbon dioxide and then enters the energy storage heat exchanger 22, the energy storage heat exchanger 22 exchanges heat with the low-temperature medium in the cold storage tank 23, and transfers the heat of the high-temperature and high-pressure gaseous carbon dioxide in the energy storage heat exchanger 22 to the low-temperature medium, so that the high-temperature and high-pressure gaseous carbon dioxide is converted into low-temperature and high-pressure gaseous carbon dioxide, and the low-temperature medium in the cold storage tank 23 is converted into a high-temperature medium and stored in the heat storage tank 24, the low-temperature and high-pressure gaseous carbon dioxide enters the liquid storage container 31, and the heat absorbing medium is introduced into the heat exchange module 32, and the heat absorbing medium The spray liquid pump 34 extracts the liquid supercooled carbon dioxide from the liquid storage container 31, and after being supercooled again by the supercooler 44, it is sprayed in the spray area RP of the liquid storage container 31 through the spray head 35. The gaseous carbon dioxide entering the liquid storage container 31 is directly mixed and contacted with the liquid supercooled carbon dioxide, so that the low-temperature and high-pressure gaseous carbon dioxide is condensed into low-temperature and high-pressure liquid carbon dioxide and stored in the liquid storage container 31.

[0083] Based on the above three embodiments, see Figure 7-10 The storage device 300 also includes a liquid replenishing tank 36, in which liquid carbon dioxide is stored (the liquid carbon dioxide stored in the liquid replenishing tank 36 can be injected through other equipment, and a valve is provided at the injection port). In one example, the liquid replenishing tank 36 is connected to the liquid storage container 31, and the liquid replenishing tank 36 is used to replenish liquid carbon dioxide into the liquid storage container 31 during the energy storage stage. In one example, the liquid replenishing tank 36 is connected to the liquid storage container 31 through a liquid replenishing pipe 37, and liquid carbon dioxide can be replenished into the liquid storage container 31 through the liquid replenishing pipe 37. In this way, the conversion efficiency of gaseous carbon dioxide is improved by supercooling and spraying the replenished liquid carbon dioxide in the liquid storage container 31 in advance (at this time, there is no need to retain liquid carbon dioxide in the liquid storage container 31, and the storage space of subsequent liquid carbon dioxide can be increased). In this example, the liquid replenishing pipe 37 is connected to the lower end of the liquid storage container 31, and liquid carbon dioxide is replenished into the liquid storage container 31 from bottom to top, which can reduce the impact of vibration.

[0084] In this example, the position of the liquid infusion tank 36 can be higher than the position of the liquid storage container 31, so that the liquid carbon dioxide in the liquid infusion tank 36 can enter the liquid storage container 31 under the action of gravity. In this example, the end of the liquid infusion tube 37 connected to the liquid infusion tank 36 is not lower than the end of the liquid infusion tube 37 connected to the liquid storage container 31, and the eighth valve 26 is provided on the liquid infusion tube 37 (the eighth valve 26 is used to adjust and control the flow of liquid carbon dioxide entering the liquid storage container 31 from the liquid infusion tank 36). In this way, there is no need to set up a liquid pump, and the liquid carbon dioxide in the liquid infusion tank 36 can flow into the liquid storage container 31 under the action of gravity. In one example, the end of the liquid infusion tube 37 connected to the liquid infusion tank 36 is higher than the end of the liquid infusion tube 37 connected to the liquid storage container 31.

[0085] In one example, a driving pump (not shown in the figure) may be provided on the liquid infusion tube 37, and the driving pump may be used to transfer the liquid carbon dioxide (for example, to transfer the liquid carbon dioxide in the liquid infusion tank 36 to the liquid storage container 31. Another example is to transfer the liquid carbon dioxide in the liquid storage container 31 to the liquid infusion tank 36). In this way, the liquid infusion tank 36 may be reused as a liquid storage tank to store liquid carbon dioxide, thereby increasing the storage space for liquid carbon dioxide.

[0086] Based on the provided liquid replenishing tank 36 and liquid replenishing tube 37, in the first working mode (energy storage stage), the eighth valve 26 is opened, and the liquid carbon dioxide in the liquid replenishing tank 36 enters the liquid storage container 31 in advance to supercool the liquid carbon dioxide.

[0087] In another example, the liquid replenishing tank 36 may also be directly connected to the spray pipe 33 (not shown in the figure) to provide the liquid carbon dioxide required by the subcooler 44 of the spray structure.

[0088] Based on the above implementation, see Fig. 9 and Fig.10The storage device 300 further includes an auxiliary liquid storage structure; the auxiliary liquid storage structure includes an auxiliary liquid storage tank 38, a first liquid storage pipe 39, a second liquid storage pipe 40, and a liquid storage pump 43. In one example, the first end of the first liquid storage pipe 39 is connected to the liquid storage area RC of the liquid storage container 31, the second end of the first liquid storage pipe 39 is connected to the auxiliary liquid storage tank 38, the first liquid storage pipe 39 is provided with a ninth valve 27, the first end of the second liquid storage pipe 40 is connected to the auxiliary liquid storage tank 38, the second end of the second liquid storage pipe 40 is connected to the liquid storage container 31 (forming a closed loop structure), the liquid storage pump 43 is provided on the second liquid storage pipe 40, and the second liquid storage pipe 40 is provided with a tenth valve 28 between the liquid storage pump 43 and the auxiliary liquid storage tank 38. In this example, the position of the auxiliary liquid storage tank 38 is lower than the position of the liquid storage container 31 (the position of the auxiliary liquid storage tank 38 is set lower than the position of the liquid storage container 31, and it is not necessary to set a liquid pump on the first liquid storage pipe 39, and only gravity is used to realize the transfer of liquid carbon dioxide from the liquid storage container 31 to the auxiliary liquid storage tank 38). In this example, the first end of the first liquid storage pipe 39 is lower than the heat exchange module 32. In the present disclosure, the auxiliary liquid storage tank 38 is set to increase the storage capacity (increase the storage space of liquid carbon dioxide). When there is a lot of liquid carbon dioxide formed in the energy storage stage, the ninth valve 27 can be opened to transfer the liquid carbon dioxide in the liquid storage container 31 to the auxiliary liquid storage tank 38 for storage. In the energy release stage, the tenth valve 28 is opened, and the liquid storage pump 43 is used to extract the liquid carbon dioxide in the auxiliary liquid storage tank 38 into the liquid storage container 31. Of course, in other examples, liquid carbon dioxide can also not be stored in the liquid storage container 31, and liquid carbon dioxide can only be stored in the auxiliary liquid storage tank 38 (liquid carbon dioxide enters the auxiliary liquid storage tank 38 through the liquid storage container 31 for storage). In another example, the liquid storage pump 43 may also be disposed on the first liquid storage pipe 39 .

[0089] In one embodiment of the present disclosure, the heat supply medium may be heating water, and the heat absorption medium may be chilled water.

[0090] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.

Claims

1. A storage device for a carbon dioxide energy storage system, characterized in that: include: A liquid storage container, wherein the internal cavity of the liquid storage container comprises a spraying area at the upper part and a liquid storage area at the lower part; the liquid storage container has at least one gaseous carbon dioxide interface in the spraying area; A heat exchange module is located in the liquid storage area; the inlet and outlet of the heat exchange module both extend outside the liquid storage container; the heat exchange module is at least used to flow in a heat supply medium to evaporate liquid carbon dioxide during the energy release stage; The spray structure comprises a spray head; the spray head is used to spray liquid supercooled carbon dioxide to the spray area during the energy storage stage, wherein the liquid supercooled carbon dioxide is liquid carbon dioxide having a temperature lower than the dew point of the gaseous carbon dioxide in the spray area.

2. The storage device of the carbon dioxide energy storage system according to claim 1, characterized in that: The spray structure also includes a spray pipe, a spray liquid pump and a supercooler; The liquid storage area of ​​the liquid storage container is connected to the spray head through the spray pipe, the spray liquid pump and the supercooler are both arranged on the spray pipe, and the supercooler is configured to reduce the temperature of the liquid carbon dioxide flowing therethrough.

3. The storage device of the carbon dioxide energy storage system according to claim 1, characterized in that: The heat exchange module is also used to cool the liquid carbon dioxide by allowing the heat absorbing medium to flow in during the energy storage stage; The spray structure also includes a spray pipe and a spray liquid pump; The liquid storage area of ​​the liquid storage container is connected with the spray head through the spray pipe, and the spray liquid pump is arranged on the spray pipe.

4. The storage device of the carbon dioxide energy storage system according to claim 1, characterized in that: The storage device further comprises a liquid replenishing tank; the liquid replenishing tank is connected to the liquid storage container via a liquid replenishing pipe; The liquid replenishing tank is used to replenish liquid carbon dioxide to the liquid storage container.

5. The storage device of the carbon dioxide energy storage system according to claim 4, characterized in that: The position of the fluid infusion tank is higher than that of the fluid storage container, and the end of the fluid infusion tube connected to the fluid infusion tank is not lower than the end of the fluid infusion tube connected to the fluid storage container.

6. The storage device of the carbon dioxide energy storage system according to claim 4, characterized in that: The fluid infusion tube is provided with a driving pump; The driving pump is at least configured to transfer at least a portion of the liquid carbon dioxide in the liquid storage container to the liquid replacement tank.

7. The storage device of the carbon dioxide energy storage system according to any one of claims 1 to 6, characterized in that: The storage device also includes an auxiliary liquid storage structure; The auxiliary liquid storage structure includes an auxiliary liquid storage tank; the inlet of the auxiliary liquid storage tank is connected to the liquid outlet of the liquid storage container through a first liquid storage tube, and the outlet of the auxiliary liquid storage tank is connected to the liquid inlet of the liquid storage container through a second liquid storage tube, and at least one of the first liquid storage tube and the second liquid storage tube is provided with a liquid storage pump.

8. The storage device of the carbon dioxide energy storage system according to claim 1, characterized in that: The heat exchange module is a heat exchange tube.

9. A carbon dioxide energy storage system, characterized in that: A storage device comprising any one of claims 1 to 8.

10. A method for operating a storage device, characterized in that: include: In the energy storage stage, liquid supercooled carbon dioxide is sprayed to condense gaseous carbon dioxide; During the energy release phase, a heat supply medium flows in to evaporate the liquid carbon dioxide.

Images