Method for selecting condenser for gas condensation in gas-liquid phase change carbon dioxide energy storage system

Abstract

The present disclosure relates to the technical field of gas-liquid phase-change carbon dioxide energy storage; specifically, to a method for selecting a condenser for gas condensation in a gas-liquid phase-change carbon dioxide energy storage system. The condenser has a condensation cavity and a condensation tube; the condensation cavity has a gaseous carbon dioxide inlet and a liquid carbon dioxide outlet; the gaseous carbon dioxide is passed into the condensation cavity from the gaseous carbon dioxide inlet, and the pressure of the gaseous carbon dioxide passed into the condensation cavity is 3MPa~10MPa; a plurality of condensation tubes parallel to each other are arranged in the condensation cavity; when the flow direction of the condensed water in each condensation tube is the same, the number of liquid carbon dioxide outlets is one; when the flow direction of the condensed water in half of the condensation tubes is opposite to the flow direction of the condensed water in the other half of the condensation tubes, the number of liquid carbon dioxide outlets is two and they are arranged in sequence along the extension direction of the condensation tubes. The method for selecting the condenser can improve the condensation effect, improve the efficiency of the condenser, reduce the gas plug phenomenon inside the condenser, and maintain the pressure balance inside the condenser.

Description

Technical Field

[0001] The present disclosure relates to the technical field of gas-liquid phase change carbon dioxide energy storage, and in particular to a method for selecting a condenser for gas condensation in a gas-liquid phase change carbon dioxide energy storage system. Background Art

[0002] The carbon dioxide energy storage system uses a condenser in a cross-flow manner to condense the high-pressure, room-temperature gaseous carbon dioxide medium through condensing water.

[0003] In actual production, when the condenser is running, gaseous carbon dioxide enters the condenser for condensation. Due to the uneven temperature distribution in the condenser tube bundle of the condenser, the cooling rate in the condenser cavity is inconsistent, which in turn makes the pressure distribution in the condenser cavity uneven, causing uneven pressure and gas plugging when the liquid carbon dioxide flows out of the condenser outlet.

[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 invention is to overcome the deficiencies of the above-mentioned prior art and to provide a method for selecting a condenser for condensing gaseous carbon dioxide in a carbon dioxide energy storage system. The method for selecting a condenser can improve the condensation effect, increase the efficiency of the condenser, reduce the gas plugging phenomenon inside the condenser, and maintain the pressure balance inside the condenser.

[0006] According to one aspect of the present disclosure, a method for selecting a condenser for gas condensation in a gas-liquid phase-change carbon dioxide energy storage system is provided, wherein the condenser has a condensation cavity and a condensation tube;

[0007] The condensation cavity has a gaseous carbon dioxide inlet and a liquid carbon dioxide outlet; the gaseous carbon dioxide is passed into the condensation cavity from the gaseous carbon dioxide inlet, and the pressure of the gaseous carbon dioxide passed into the condensation cavity is 3MPa~10MPa;

[0008] A plurality of condensation tubes parallel to each other are arranged in the condensation cavity; the condensation tubes are used to circulate condensed water;

[0009] When the condensed water in each of the condensing pipes flows in the same direction and the carbon dioxide flow rate in the gas-liquid phase change carbon dioxide energy storage system is less than the flow rate of a 50MW grade compressor, the number of the liquid carbon dioxide outlets is one;

[0010] When the flow direction of the condensed water in half of the condenser tubes is opposite to the flow direction of the condensed water in the other half of the condenser tubes and the carbon dioxide flow rate in the gas-liquid phase change carbon dioxide energy storage system exceeds the 50MW grade compressor flow rate, the number of the liquid carbon dioxide outlets is multiple and they are arranged in sequence along the extension direction of the condenser tubes.

[0011] In one embodiment of the present disclosure, the gaseous carbon dioxide inlet is located at the upper end of the condensation cavity, and the liquid carbon dioxide outlet is located at the lower end of the condensation cavity; and the condensation tube is arranged horizontally.

[0012] In one embodiment of the present disclosure, the condenser further comprises a water separation structure and a water collection structure;

[0013] The condenser has a plurality of tube groups, each of which includes at least one condensing tube;

[0014] When the tube group includes one condenser tube, the water distribution structure is connected to the inlet of each condenser tube, and the water collection structure is connected to the outlet of each condenser tube;

[0015] When the tube group includes at least two condensing tubes, the at least two condensing tubes are connected in sequence to form a medium tube, the water distribution structure is connected to the inlet of each medium tube, and the water collection structure is connected to the outlet of each medium tube;

[0016] The water distribution structure and the water collection structure are distributed on both sides of the condensation cavity.

[0017] In one embodiment of the present disclosure, the water diversion structure and the water collection structure are distributed on the same side of the condensation cavity.

[0018] In one embodiment of the present disclosure, the condenser has multiple tube groups, each tube group includes two condenser tubes; the two condenser tubes are connected end to end to form a medium tube, and the flow direction of condensed water in half of the medium tubes is opposite to the flow direction of condensed water in the other half of the medium tubes.

[0019] In one embodiment of the present disclosure, the flow directions of condensed water in two adjacent medium pipes are opposite.

[0020] In one embodiment of the present disclosure, in the tube group, two of the condensing tubes are connected end to end in sequence via a connecting tube;

[0021] The connecting pipe is placed inside the condensing cavity, or the connecting pipe is placed outside the condensing cavity.

[0022] In one embodiment of the present disclosure, when the flow direction of the condensed water in half of the condenser is opposite to the flow direction of the condensed water in the other half of the condenser and the carbon dioxide flow rate in the gas-liquid phase change carbon dioxide energy storage system exceeds the 50MW grade compressor flow rate, the number of the liquid carbon dioxide outlets is two, and they are arranged sequentially along the extension direction of the condenser.

[0023] In one embodiment of the present disclosure, the condenser has a plurality of tube groups, each tube group includes a plurality of condensing tubes; the plurality of condensing tubes are sequentially connected end to end to form a medium tube.

[0024] 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

[0025] 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.

[0026] Figure 1 This is a schematic diagram of the principle of a carbon dioxide energy storage system in one embodiment of the present disclosure.

[0027] Figure 2 This is a schematic diagram of the principle of a carbon dioxide energy storage system in one embodiment of the present disclosure.

[0028] Figure 3 This is a schematic diagram of the principle of a carbon dioxide energy storage system in one embodiment of the present disclosure.

[0029] Figure 4 This is a schematic diagram of the structure of a condenser in one embodiment of the present disclosure.

[0030] Figure 5 This is a schematic diagram of the structure of a condenser in one embodiment of the present disclosure.

[0031] Figure 6 This is a schematic diagram of the structure of a condenser in one embodiment of the present disclosure.

[0032] Figure 7 A schematic diagram of the structure of a condenser in one embodiment of the present disclosure.

[0033] Description of reference numerals:

[0034] 100. Gas storage container; 200. Energy storage component; 201. Compression energy storage unit; 21. Compressor; 22. Energy storage heat exchanger; 23. Condenser; 231. Condensation chamber; 232. Condenser pipe; 233. Water distribution structure; 234. Water collection structure; 235. Connecting pipe; 236. Flow guide pipe; 300. Liquid storage container; 400. Energy release component; 401. Expansion energy release unit; 41. Turbine; 42. Energy release heat exchanger; 43. Evaporator; A. Gaseous carbon dioxide inlet; B. Liquid carbon dioxide outlet. DETAILED DESCRIPTION

[0035] 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.

[0036] 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.

[0037] The terms "a", "an", "the", "said" and "at least two" are used to indicate the presence of one or more elements / components / 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", etc. are used merely as labels and are not intended to limit the quantity of their objects.

[0038] In this disclosure, a plurality refers to a number of three or more.

[0039] Cross-flow heat transfer refers to a method of improving heat exchange efficiency by making the hot and cold fluids flow in opposite directions.

[0040] The large-scale development of renewable energy represented by wind power and photovoltaics has become an inevitable trend in energy development. However, due to the intermittent, uncertain, and periodic characteristics of renewable energy, the current power system is facing severe problems such as increasing load fluctuations and increasing demand for regulation capabilities. Therefore, the consumption and grid connection of renewable energy is one of the main bottlenecks restricting sustainable development, and large-scale energy storage systems can effectively solve this problem.

[0041] As a large-scale energy storage system, carbon dioxide energy storage technology is widely used because of its low critical point parameters, stable chemical properties of the working fluid, high thermal stability, and the inability and non-support of combustion, and the system has no risk of explosion. For the relevant introduction of carbon dioxide energy storage technology, please refer to patents CN221858310U, CN118826303A, CN118687074A, etc.

[0042] An embodiment of the present disclosure provides a carbon dioxide energy storage system. Figure 1 , the carbon dioxide energy storage system includes a gas storage container 100, an energy storage component 200, a liquid storage container 300 and an energy release component 400. In this example, the gas storage container 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 liquid storage container 300, the outlet of the liquid storage container 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 container 100. Among them, the gas storage container 100 can store gaseous carbon dioxide; the liquid storage container 300 can store liquid carbon dioxide.

[0043] The energy storage component 200 can use electricity to compress the gaseous carbon dioxide from the gas storage container 100 to achieve energy storage; the energy release component 400 can expand the liquid carbon dioxide from the liquid storage container 300 to generate electricity. The energy storage component 200 can also cool the compressed gaseous carbon dioxide, for example, cool the compressed gaseous carbon dioxide to condense it into liquid carbon dioxide, or allow the cooled gaseous carbon dioxide to enter the liquid storage container 300 and be condensed into liquid carbon dioxide. The energy release component 400 can also heat the liquid carbon dioxide, for example, evaporate the liquid carbon dioxide provided from the liquid storage container 300 into gaseous carbon dioxide, then heat it up, and expand the heated gaseous carbon dioxide to generate electricity, or heat the gaseous carbon dioxide provided by pre-evaporation in the energy release component 400, and expand the heated gaseous carbon dioxide to generate electricity.

[0044] For example, in the energy storage stage, the energy storage component 200 can compress and condense the gaseous carbon dioxide from the gas storage container 100, thereby causing the gaseous carbon dioxide to phase-change into liquid carbon dioxide and store it in the liquid storage container 300. In the energy release stage, the energy release component 400 can evaporate and expand the liquid carbon dioxide from the liquid storage container 300 to generate electricity, thereby causing the generated gaseous carbon dioxide to be stored in the gas storage container 100.

[0045] exist Figure 1~Figure 3 In the example, the number of liquid storage containers 300 is one. It is understandable that in the embodiment of the present disclosure, the number of liquid storage containers 300 may also be multiple. When the number of liquid storage containers 300 is multiple, these liquid storage containers 300 may be connected in series, or in parallel, or may be connected in a mixed manner of series and parallel.

[0046] In one embodiment of the present disclosure, see Figure 2 The energy release assembly 400 includes at least one expansion energy release part 401, and each expansion energy release part 401 is connected to the gas storage container 100 and the liquid storage container 300. Specifically, the inlet of each expansion energy release part 401 is connected to the liquid storage container 300, and the outlet of each expansion energy release part 401 is connected to the gas storage container 100.

[0047] exist Figure 2 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).

[0048] 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 2 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 three or more.

[0049] exist Figure 2In 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 liquid storage container 300 and expands and cools down exchanges heat with the heating medium with a higher temperature, thereby heating the carbon dioxide and raising its temperature, which can recover the cold energy generated by the expansion of the gaseous carbon dioxide.

[0050] In one embodiment of the present disclosure, see Figure 2 , the outlet of the last stage turbine 41 of the expansion energy release part 401 is connected to the gas storage container 100. It can be understood that when the expansion energy release part 401 has only one expansion energy release unit, the outlet of the turbine 41 of the expansion energy release part 401 is connected to the gas storage container 100. Optionally, a valve is provided between the outlet of the last stage turbine 41 of the expansion energy release part 401 and the gas storage container 100.

[0051] In one embodiment of the present disclosure, see Figure 2 , the expansion energy release part 401 may also have an evaporator 43, which is disposed between the first-stage expansion energy release unit and the liquid storage container 300. In other words, the carbon dioxide inlet of the first-stage energy release heat exchanger 42 may be connected to the carbon dioxide outlet of the evaporator 43, and the carbon dioxide inlet of the evaporator 43 may be connected to the outlet of the liquid storage container 300. The evaporator 43 may heat the liquid carbon dioxide from the liquid storage container 300, so that the liquid carbon dioxide from the liquid storage container 300 evaporates into gaseous carbon dioxide and flows into the energy release heat exchanger 42.

[0052] In one embodiment of the present disclosure, see Figure 3 The energy storage assembly 200 includes at least one compressed energy storage unit 201; each compressed energy storage unit 201 is connected to the gas storage container 100 and the liquid storage container 300. Specifically, the inlet of each compressed energy storage unit 201 is connected to the gas storage container 100, and the outlet of each compressed energy storage unit 201 is connected to the liquid storage container 300.

[0053] exist Figure 3 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 one, for example, it can be one, or a plurality of other numbers (for example, 2, 4, 5 or 6).

[0054] 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. Figure 3, a compression 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 compression energy storage part 201 includes a plurality of compression energy storage units cascaded in sequence, between two adjacent compression energy storage units, the carbon dioxide outlet of the energy storage heat exchanger 22 of the upper compression energy storage unit is connected to the inlet of the compressor 21 of the lower compression energy storage unit. Figure 3 In the example, the compressed energy storage unit 201 includes two compressed energy storage units. It is understandable that, according to needs, the compressed energy storage unit in the compressed energy storage unit 201 can be one, or two or more. The compressor 21 can compress the gaseous carbon dioxide from the gas storage container 100 under the power drive, and the compressed carbon dioxide can be heat exchanged and cooled in the energy storage heat exchanger 22.

[0055] exist Figure 3 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.

[0056] In one embodiment of the present disclosure, see Figure 3 , the inlet of the first-stage compressor 21 of the compression energy storage part 201 is connected to the gas storage container 100. It can be understood that when the compression energy storage part 201 has only one compression energy storage unit, the inlet of the compressor 21 of the compression energy storage part 201 is connected to the gas storage container 100. Further, a valve may be provided between the inlet of the first-stage compressor 21 and the gas storage container 100.

[0057] In one embodiment of the present disclosure, the compressed energy storage unit 201 may further include a condenser 23, which is disposed between the last stage compressed energy storage unit and the liquid storage container 300. In other words, the carbon dioxide outlet of the last stage energy storage heat exchanger 22 may be connected to the carbon dioxide inlet of the condenser 23, and the carbon dioxide outlet of the condenser 23 may be connected to the inlet of the liquid storage container 300. The condenser 23 may condense the carbon dioxide from the compressed energy storage unit, so that the carbon dioxide from the compressed energy storage unit is condensed into liquid carbon dioxide and stored in the liquid storage container 300.

[0058] In actual production, when the condenser is running, gaseous carbon dioxide enters the condenser for condensation. Due to the uneven temperature distribution in the condenser tube bundle of the condenser, the cooling rate in the condenser cavity is inconsistent, which in turn causes uneven pressure distribution in the condenser cavity, causing uneven pressure and gas plugging when the liquid carbon dioxide flows out of the condenser outlet. Specifically:

[0059] In the related art, the condensing chamber of the condenser is provided with a gaseous carbon dioxide inlet and two liquid carbon dioxide outlets, and the two liquid carbon dioxide outlets are connected to the same main pipe through a guide tube. A plurality of parallel condensing tubes are arranged in the condensing chamber, and the water flow direction of the condensed water in the plurality of condensing tubes is the same, and the two liquid carbon dioxide outlets are arranged along the extension direction of the condensing tubes. During the condensation process of the condenser, as the heat exchange between the gaseous carbon dioxide and the condensed water proceeds, the temperature of the condensed water at the rear end of the condensing chamber is higher than the temperature of the condensed water at the front end of the condensing chamber (the end where the condensed water flows into the condensing chamber is the front end, and the end where the condensed water flows out of the condensing chamber is the rear end). In this way, the gaseous carbon dioxide flowing through the front end of the condensing chamber can be completely phase-changed into liquid carbon dioxide, and discharged from the guide tube connected to the liquid carbon dioxide outlet at the front end of the condensing chamber, while the gaseous carbon dioxide flowing through the rear end of the condensing chamber is partially phase-changed into liquid carbon dioxide or does not phase-changed into liquid carbon dioxide at all, and continues to remain in a gaseous state. When high-pressure gaseous carbon dioxide is continuously introduced into the gaseous carbon dioxide inlet, most of the gaseous carbon dioxide remaining after phase change in the condensation chamber will be discharged from the guide tube connected to the liquid carbon dioxide outlet at the rear end of the condensation chamber. When the guide tubes connected to the two liquid carbon dioxide outlets discharge carbon dioxide at the same time, the guide tube at the rear end of the condensation chamber is prone to uneven pressure and air blockage.

[0060] In order to solve at least one of the above problems, the structure of the condenser is optimized in the present disclosure to overcome the above defects.

[0061] In the first embodiment of the present disclosure, the structure of the condenser 23 is optimized, and the number of the liquid carbon dioxide outlet B is set to one.

[0062] In one embodiment of the present disclosure, see Figure 4The condenser 23 has a condensation cavity 231 and a condensation tube 232. The condensation cavity 231 has a gaseous carbon dioxide inlet A and a liquid carbon dioxide outlet B. The gaseous carbon dioxide inlet A is used to introduce gaseous carbon dioxide into the condensation cavity 231, and the liquid carbon dioxide outlet B is used to flow out the liquid carbon dioxide that has undergone condensation phase change in the condensation cavity 231. In this example, the condenser 23 has a plurality of tube groups, and each tube group has a condensation tube 232. It can be understood that the number of condensation tubes 232 is multiple, and the multiple condensation tubes 232 are arranged in parallel with each other. Condensed water is circulated in the condensation tube 232, and the flow direction of the condensed water intersects with the flow direction of the carbon dioxide, thereby forming cross-flow heat conduction, which can accelerate the condensation efficiency.

[0063] In one embodiment of the present disclosure, the pressure of the gaseous carbon dioxide introduced into the condensation chamber 231 is between 3 MPa and 10 MPa. In this way, it can be ensured that the condenser 23 using condensed water for condensation has a good condensation effect on the gaseous carbon dioxide.

[0064] In one embodiment of the present disclosure, see Figure 4 The gaseous carbon dioxide inlet A is located at the upper end of the condensation cavity 231, and the liquid carbon dioxide outlet B is located at the lower end of the condensation cavity 231; the condensation tube 232 is arranged horizontally. In this way, the flow direction of the condensed water in the condensation tube 232 and the flow direction of the carbon dioxide can be perpendicularly intersected to achieve a better condensation effect, and it is also beneficial to the extraction of liquid carbon dioxide.

[0065] In this example, see Figure 4 , the number of liquid carbon dioxide outlets B is one. Thus, when there is only one liquid carbon dioxide outlet B, the liquid carbon dioxide formed by condensation phase change is led out from the same liquid carbon dioxide outlet guide pipe 236 to the main pipeline, or the liquid carbon dioxide and gaseous carbon dioxide mixture is led out from the same liquid carbon dioxide outlet guide pipe 236 to the main pipeline, thereby reducing the possibility of gas blockage.

[0066] In one embodiment of the present disclosure, see Figure 4 , the water flow direction of the condensed water in the condenser tube 232 is the same. The condenser 23 also has a water distribution structure 233 and a water collection structure 234. In this example, the water flow direction of the condensed water in the condenser tube 232 is the same, and the water distribution structure 233 is located on one side of the condenser 23, and is connected to the inlet of each condenser tube 232. The water collection structure 234 is located on the other side of the condenser tube 232, and is connected to the outlet of each condenser tube 232. The water distribution structure 233 passes the condensed water into each condenser tube 232, and after passing through the condenser tube 232 (after completing heat exchange with carbon dioxide), it flows out to the water collection structure 234 for the next step of processing.

[0067] In one embodiment of the present disclosure, the condensation pipe 232 extends from the front end of the condensation chamber 231 (at Figure 4 The left side is the front end of the condensation chamber 231) extending to the rear end of the condensation chamber 231 (in Figure 4 In the figure, the right side is the rear end of the condensation chamber 231). The present disclosure does not limit the shape of the condensation tube 232. The cross section of the condensation tube 232 along the direction perpendicular to its extension (perpendicular to the paper surface) can be circular, quadrilateral, pentagonal, etc., and the condensation tube 232 along the direction of its extension (parallel to the paper surface) can be a straight tube, a V-shaped tube, a serpentine tube, an arc tube, etc.

[0068] In one embodiment of the present disclosure, see Figure 3 , the area of ​​the gaseous carbon dioxide inlet A can be larger than the area of ​​the liquid carbon dioxide outlet B. In other words, the orthographic projection area of ​​the gaseous carbon dioxide inlet A in the column direction can be larger than the orthographic projection area of ​​the liquid carbon dioxide outlet B in the column direction. This is because the volume of high-pressure and room-temperature gaseous carbon dioxide decreases during the phase transition to low-pressure liquid carbon dioxide. Therefore, increasing the area of ​​the gaseous carbon dioxide inlet A can speed up the condensation efficiency, thereby improving the working efficiency of the carbon dioxide energy storage system.

[0069] When the structure of the condenser 23 in the first embodiment of the present disclosure is adopted, the carbon dioxide flow rate in the gas-liquid phase-change carbon dioxide energy storage system is less than the flow rate of the 50MW-class compressor, so that a better condensation effect and condensation efficiency can be ensured.

[0070] In the second embodiment of the present disclosure, the structure of the condenser 23 is optimized, and the number of the liquid carbon dioxide outlet B is set to one.

[0071] In one embodiment of the present disclosure, the condenser 23 has a condensation cavity 231 and a condensation tube 232. The condensation cavity 231 has a gaseous carbon dioxide inlet A and a liquid carbon dioxide outlet B. The gaseous carbon dioxide inlet A is used to introduce gaseous carbon dioxide into the condensation cavity 231, and the liquid carbon dioxide outlet B is used to flow out the liquid carbon dioxide that has undergone condensation phase change in the condensation cavity 231. In this example, the condenser 23 has a plurality of tube groups, each tube group has a condensation tube 232. It can be understood that the number of condensation tubes 232 is multiple, and the multiple condensation tubes 232 are arranged in parallel with each other. Condensed water is circulated in the condensation tube 232, and the flow direction of the condensed water intersects with the flow direction of the carbon dioxide, thereby forming cross-flow heat conduction, which can accelerate the condensation efficiency.

[0072] In one embodiment of the present disclosure, the pressure of the gaseous carbon dioxide introduced into the condensation chamber 231 is between 3 MPa and 10 MPa, so that the condenser 23 using condensed water for condensation can ensure a good condensation effect on the gaseous carbon dioxide.

[0073] In one embodiment of the present disclosure, the gaseous carbon dioxide inlet A is located at the upper end of the condensation chamber 231, and the liquid carbon dioxide outlet B is located at the lower end of the condensation chamber 231; the condensation tube 232 is arranged horizontally. In this way, it can ensure good condensation efficiency and facilitate the extraction of liquid carbon dioxide.

[0074] In this example, there is one liquid carbon dioxide outlet B. Thus, when there is only one liquid carbon dioxide outlet B, the liquid carbon dioxide formed by condensation phase change is led out from the same liquid carbon dioxide outlet flow guide pipe 236 to the main pipeline, or the liquid carbon dioxide and gaseous carbon dioxide mixture is led out from the same liquid carbon dioxide outlet flow guide pipe 236 to the main pipeline, thereby reducing the possibility of gas blockage.

[0075] In one embodiment of the present disclosure, the flow direction of the condensed water in a part of the condenser tube 232 is opposite to the flow direction of the condensed water in another part of the condenser tube 232. In this way, the condensed water in different flow directions in the condenser tube 232 intersects with the flow direction of the carbon dioxide, and both form cross-flow heat conduction; at the same time, the flow direction of the condensed water in a part of the condenser tube 232 is set to be opposite to the flow direction of the condensed water in another part of the condenser tube 232, so that the front end of the condensation cavity 231 and the rear end of the condensation cavity 231 are both injected with condensed water with lower temperature, which can balance the condensation effect in the condensation cavity 231 and reduce the pressure difference between the front end of the condensation cavity 231 and the rear end of the condensation cavity 231. In one example, the flow direction of the water in half of the condenser tube 232 is opposite to the flow direction of the water in the other half of the condenser tube 232. In this way, the condensation effect at the front end of the condensation cavity 231 and the rear end of the condensation cavity 231 is basically the same. For example, when a plurality of condenser tubes 232 are arranged in sequence along the Z axis, the flow directions of the condensed water in any two adjacent condenser tubes 232 are opposite. For another example, when multiple condensing tubes 232 are arranged in sequence along the Y axis, the flow directions of condensed water in any two adjacent condensing tubes 232 are opposite. For another example, when multiple condensing tubes 232 are arranged along the Y axis and along the Z axis at the same time, any two adjacent columns of condensing tubes 232 can be arranged staggered along the Y axis, and the flow directions of condensed water in adjacent columns of condensing tubes 232 can be opposite. The present disclosure does not limit the arrangement of the condensing tubes 232, and other arrangements may also be used in other examples.

[0076] In one embodiment of the present disclosure, the condenser 23 further has a water-dividing structure 233 and a water-collecting structure 234, wherein the water-dividing structure 233 is connected to the inlet of each condensing tube 232, and the water-collecting structure 234 is connected to the outlet of each condensing tube 232. In this example, the water flow direction of the condensed water in one half of the condensing tube 232 is opposite to the water flow direction of the condensed water in the other half of the condensing tube 232. Under this water flow direction, the water-dividing structure 233 and the water-collecting structure 234 are simultaneously arranged on the same side of the condensing cavity 231. It can be understood that the first side of the condenser 23 has the water-dividing structure 233 and the water-collecting structure 234, the water-dividing structure 233 on the first side is connected to the inlet of each condensing tube 232 on the first side, and the water-collecting structure 234 on the first side is connected to the outlet of each condensing tube 232 on the first side. At the same time, the second side of the condenser 23 also has a water distribution structure 233 and a water collection structure 234. The water distribution structure 233 on the second side is connected to the inlet of each condensation tube 232 on the second side, and the water collection structure 234 on the second side is connected to the outlet of each condensation tube 232 on the second side.

[0077] In one embodiment of the present disclosure, the condenser 232 extends from the front end of the condenser cavity 231 to the rear end of the condenser cavity 231. The present disclosure does not limit the shape of the condenser 232. The cross section of the condenser 232 perpendicular to its extension direction can be circular, quadrilateral, pentagonal, etc., and the condenser 232 can be a straight tube, a V-shaped tube, a serpentine tube, an arc tube, etc. along its extension direction.

[0078] In other examples of the present disclosure, the number of liquid carbon dioxide outlets B may be multiple, for example, two, three, four, etc., and the multiple liquid carbon dioxide outlets B are arranged in sequence along the extension direction of the condenser 232.

[0079] The structure of the condenser 23 in the second embodiment of the present disclosure can be applied to both the gas-liquid phase change carbon dioxide energy storage system in which the carbon dioxide flow rate is less than the 50MW level compressor flow rate, and the gas-liquid phase change carbon dioxide energy storage system in which the carbon dioxide flow rate exceeds the 50MW level compressor flow rate. Therefore, in actual application, it can be selected according to demand. Among them, in the present disclosure, the gas-liquid phase change carbon dioxide energy storage system in which the carbon dioxide flow rate exceeds the 50MW level compressor flow rate includes a gas-liquid phase change carbon dioxide energy storage system in which the carbon dioxide flow rate is equal to the 50MW level compressor flow rate and a gas-liquid phase change carbon dioxide energy storage system in which the carbon dioxide flow rate is greater than the 50MW level compressor flow rate.

[0080] In the third embodiment of the present disclosure, the structure of the condenser 23 is optimized, and the number of the liquid carbon dioxide outlet B is set to one.

[0081] In one embodiment of the present disclosure, see Figure 5 and Figure 6, the condenser 23 has a condensation cavity 231 and a condensation tube 232. Among them, the condensation cavity 231 has a gaseous carbon dioxide inlet A and a liquid carbon dioxide outlet B, the gaseous carbon dioxide inlet A is used to pass gaseous carbon dioxide into the condensation cavity 231, and the liquid carbon dioxide outlet B is used to flow out the liquid carbon dioxide formed by condensation phase change in the condensation cavity 231. In this example, the condenser 23 has a plurality of tube groups, each tube group has two condensation tubes 232, it can be understood that the number of condensation tubes 232 is multiple, the plurality of condensation tubes 232 are arranged in parallel with each other, the two condensation tubes 232 in the same tube group are connected end to end to form a medium tube, and the water flow direction of the condensed water in the two adjacent medium tubes is opposite. By setting the water flow direction of the condensed water to be opposite, the front end of the condensation cavity 231 and the rear end of the condensation cavity 231 are both injected with condensed water with a lower temperature, thereby making the condensation efficiency and condensation effect in the condensation cavity 231 more uniform, so that the pressure at the front end of the condensation cavity 231 and the rear end of the condensation cavity 231 are basically the same, reducing the occurrence of gas plugging.

[0082] In one example, the tube group includes two adjacent condensing tubes 232, and the water flow directions of the condensed water in the two condensing tubes 232 in each tube group are opposite, and the water flow directions of the condensed water in the two adjacent medium tubes are opposite. In this way, the condensation effect and condensation efficiency can be improved. For example, the two adjacent medium tubes can be arranged in sequence along the Z axis, and the two condensing tubes 232 in the medium tube are also arranged in sequence along the same Z axis. In the lower medium tube, the water flow direction of the condensed water in the condensing tube 232 located above is opposite to the water flow direction of the condensed water in the condensing tube 232 located below in the upper medium tube. For another example, the two adjacent medium tubes can be arranged in sequence along the Y axis, and the two condensing tubes 232 in the medium tube are also arranged in sequence along the same Y axis. In the medium tube on the left, the water flow direction of the condensed water in the condensing tube 232 located on the right is opposite to the water flow direction of the condensed water in the condensing tube 232 located on the left in the medium tube on the right. For another example, the two adjacent medium tubes can be nested. That is, one medium tube is located outside another medium tube, and the flow directions of condensed water in the two medium tubes are opposite. In other examples, the medium tubes may also be arranged in other ways, and the flow directions of condensed water in two adjacent condensing tubes are opposite in two adjacent medium tubes. In other examples, it can be set according to needs and the size of the condensing chamber 231.

[0083] In one embodiment of the present disclosure, see Figure 5 and Figure 6, one end of the two condensing tubes 232 in the tube group can be connected through the connecting tube 235. In this way, it is only necessary to directly connect the connecting tube 235 at one end of the two condensing tubes 232 to conduct, and there is no need to redesign and modify the condensing tubes 232. In addition, the provided connecting tube 235 can connect any two condensing tubes 232 as required, and has high flexibility. In one example, the connecting tube 235 is placed inside the condensing chamber 231, so that the condensed water flowing through the connecting tube 235 can participate in the condensation of carbon dioxide, which can improve the condensation effect and the efficiency of condensation. In another example, the connecting tube 235 is placed outside the condensing chamber 231. In this way, it can be adapted to various different condensation needs, that is, the connection position of the connecting tube 235 can be adjusted at any time according to the needs, which is more flexible and can reduce costs.

[0084] In other embodiments of the present disclosure, the tube group may include a plurality of condensing tubes 232, and the plurality of condensing tubes 232 are sequentially connected to form a serpentine tube. For example, the number of the condensing tubes 232 may be three, four, five, and so on.

[0085] In one embodiment of the present disclosure, the pressure of the gaseous carbon dioxide introduced into the condensation chamber 231 is between 3 MPa and 10 MPa, so that the condenser 23 using condensed water for condensation can ensure a good condensation effect on the gaseous carbon dioxide.

[0086] In one embodiment of the present disclosure, the gaseous carbon dioxide inlet A is located at the upper end of the condensation chamber 231, and the liquid carbon dioxide outlet B is located at the lower end of the condensation chamber 231; the condensation pipe 232 is arranged horizontally, which is conducive to the extraction of liquid carbon dioxide.

[0087] In this example, there is one liquid carbon dioxide outlet B. Thus, when there is only one liquid carbon dioxide outlet B, the liquid carbon dioxide formed by condensation phase change is led out from the same liquid carbon dioxide outlet flow guide pipe 236 to the main pipeline, or the liquid carbon dioxide and gaseous carbon dioxide mixture is led out from the same liquid carbon dioxide outlet flow guide pipe 236 to the main pipeline, thereby reducing the possibility of gas blockage.

[0088] In one embodiment of the present disclosure, the condenser 23 further comprises a water distribution structure 233 and a water collection structure 234, wherein the water distribution structure 233 is connected to the inlet of each medium pipe, and the water collection structure 234 is connected to the outlet of each medium pipe. Figure 5 , the water inlets and outlets of all medium pipes are located on the same side of the condensation chamber 231. In this structure, the water distribution structure 233 and the water collection structure 234 are simultaneously located on the same side of the condensation chamber 231. In another example, see Figure 6The water inlet and the water outlet of a part of the medium tubes are located on the first side of the condensation cavity 231 , and the water inlet and the water outlet of another part of the medium tubes are located on the second side of the condensation cavity 231 .

[0089] The structure of the condenser 23 in the third embodiment of the present disclosure can be applied to both the gas-liquid phase-change carbon dioxide energy storage system with a carbon dioxide flow rate less than the flow rate of a 50MW-class compressor and the gas-liquid phase-change carbon dioxide energy storage system with a carbon dioxide flow rate exceeding the flow rate of a 50MW-class compressor, but since there is only one liquid carbon dioxide outlet B. Therefore, the carbon dioxide flow rate of the carbon dioxide energy storage system cannot be too large, and in actual application, it can be selected according to demand.

[0090] In the fourth embodiment of the present disclosure, the structure of the condenser 23 in the fourth embodiment differs from the structure of the condenser 23 in the third embodiment in that:

[0091] See also Figure 7 , the number of liquid carbon dioxide outlets B is at least two, and the multiple liquid carbon dioxide outlets B are arranged in sequence along the extension direction of the condenser tube 232. In this way, the amount of liquid carbon dioxide discharged can be increased, and because the water flow directions of the condensed water are set in opposite directions, condensed water is injected into the front end of the condensation cavity 231 and the rear end of the condensation cavity 231, thereby making the condensation efficiency and condensation effect in the condensation cavity 231 more uniform, so that the pressure at the front end of the condensation cavity 231 and the rear end of the condensation cavity 231 are basically the same, and when the multiple liquid carbon dioxide outlets B are discharged to the main pipeline, the gas plug phenomenon at the rear end of the condensation cavity 231 can be reduced, or the gas plug phenomenon at the rear end of the condensation cavity 231 can be completely avoided.

[0092] The structure proposed in the fourth embodiment of the present disclosure is particularly suitable for the carbon dioxide energy storage system of a large unit (a gas-liquid phase change carbon dioxide energy storage system with a carbon dioxide flow exceeding a 50MW-level compressor flow).

[0093] In the present disclosure, the structures of the above-mentioned multiple condensers 23 proposed are simple in structure, improve the condensation efficiency and condensation effect, and reduce the occurrence of gas lock phenomenon.

[0094] In summary, the multiple solutions of the condenser 23 structure proposed in the present disclosure can be adjusted according to the energy release power of the carbon dioxide energy storage system to reduce the pressure imbalance and gas lock problems in the condenser 23.

[0095] Based on the above structure, the carbon dioxide energy storage system has the following two working modes:

[0096] See also Figure 3In the first working mode, the gaseous carbon dioxide in the gas storage container 100 passes through the compressor 21, the energy storage heat exchanger 22, and the condenser 23 in sequence, and then changes into high-pressure liquid carbon dioxide and is stored in the liquid storage container 300. During the power off period, the carbon dioxide energy storage system can operate according to the first working mode, using surplus power to drive the compression of gaseous carbon dioxide, condense it into liquid carbon dioxide and store it, and at the same time store the heat energy generated during the compression process.

[0097] See also Figure 2 In the second working mode, the liquid carbon dioxide in the liquid storage container 300 changes into gaseous carbon dioxide after passing through the evaporator 43, the energy-releasing heat exchanger 42 and the turbine 41, and is stored in the gas storage container 100. This mode is used to work during peak hours of electricity consumption, using low-grade heat to gasify the liquid carbon dioxide, and using the heat energy stored in the first working mode to promote the expansion of the gaseous carbon dioxide, drive the turbine 41 to generate electricity, and store the expanded gaseous carbon dioxide at normal temperature and pressure in the gas storage container 100 for the next cycle.

[0098] It is understood that in other embodiments of the present disclosure, the gas-liquid phase-change carbon dioxide energy storage system may also be provided with other components. In one example, the gas-liquid phase-change carbon dioxide energy storage system may also be provided with a heat recovery component, which includes a heat storage tank and a cold storage tank. In the energy storage stage, the energy storage heat exchanger 22 may exchange heat with the low-temperature medium from the cold storage tank (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 stored in the heat storage tank. In the energy release stage, the energy release heat exchanger 42 may exchange heat with the high-temperature medium from the heat storage tank (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 stored in the cold storage tank. In this example, the heating medium and the cooling medium are heat exchange media circulating between the heat storage tank and the cold storage tank, and the temperature states of the two are different.

[0099] 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 method for selecting a condenser for gas condensation in a gas-liquid phase change carbon dioxide energy storage system, characterized in that: The condenser comprises a condensation cavity and a condensation tube; The condensation cavity has a gaseous carbon dioxide inlet and a liquid carbon dioxide outlet; the gaseous carbon dioxide is passed into the condensation cavity from the gaseous carbon dioxide inlet, and the pressure of the gaseous carbon dioxide passed into the condensation cavity is 3MPa~10MPa; A plurality of condensation tubes parallel to each other are arranged in the condensation cavity; the condensation tubes are used to circulate condensed water; When the condensed water in each of the condensing pipes flows in the same direction and the carbon dioxide flow rate in the gas-liquid phase change carbon dioxide energy storage system is less than the flow rate of a 50MW grade compressor, the number of the liquid carbon dioxide outlets is one; When the flow direction of the condensed water in half of the condenser tubes is opposite to the flow direction of the condensed water in the other half of the condenser tubes and the carbon dioxide flow rate in the gas-liquid phase change carbon dioxide energy storage system exceeds the 50MW grade compressor flow rate, the number of the liquid carbon dioxide outlets is two, and they are arranged in sequence along the extension direction of the condenser tubes.

2. The method for selecting a condenser for gas condensation in the gas-liquid phase change carbon dioxide energy storage system according to claim 1, characterized in that: The gaseous carbon dioxide inlet is located at the upper end of the condensation cavity, and the liquid carbon dioxide outlet is located at the lower end of the condensation cavity; the condensation pipe is arranged horizontally.

3. The method for selecting a condenser for gas condensation in the gas-liquid phase change carbon dioxide energy storage system according to claim 1, characterized in that: The condenser also includes a water distribution structure and a water collection structure; The condenser has a plurality of tube groups, each of which includes at least one condensing tube; When the tube group includes one condenser tube, the water distribution structure is connected to the inlet of each condenser tube, and the water collection structure is connected to the outlet of each condenser tube; When the tube group includes two condensing tubes, the two condensing tubes are connected in sequence to form a medium tube, the water distribution structure is connected to the inlet of each medium tube, and the water collection structure is connected to the outlet of each medium tube; The water distribution structure and the water collection structure are distributed on both sides of the condensation cavity.

4. The method for selecting a condenser for gas condensation in the gas-liquid phase change carbon dioxide energy storage system according to claim 1, characterized in that: The condenser also includes a water distribution structure and a water collection structure; The condenser has a plurality of tube groups, each of which includes at least one condensing tube; When the tube group includes one condenser tube, the water distribution structure is connected to the inlet of each condenser tube, and the water collection structure is connected to the outlet of each condenser tube; When the tube group includes two condensing tubes, the two condensing tubes are connected in sequence to form a medium tube, the water distribution structure is connected to the inlet of each medium tube, and the water collection structure is connected to the outlet of each medium tube; The water distribution structure and the water collection structure are distributed on the same side of the condensation cavity.

5. The method for selecting a condenser for gas condensation in the gas-liquid phase change carbon dioxide energy storage system according to claim 3 or 4, characterized in that: In the tube group, two condensing tubes are connected end to end in sequence through a connecting tube; The connecting pipe is placed inside the condensing cavity, or the connecting pipe is placed outside the condensing cavity.

Images