CN116952046B - Energy storage system based on working medium gas-liquid phase change - Google Patents
Energy storage system based on working medium gas-liquid phase change Download PDFInfo
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Abstract
The embodiment of the invention relates to an energy storage system based on gas-liquid phase change of working medium, which comprises a gas storage, an energy storage component, a liquid storage tank and an ejector. The energy storage assembly comprises a compression energy storage part and a working medium condenser, the gas storage is connected with a working medium inlet of the compression energy storage part, a working medium outlet of the compression energy storage part is connected with a first inlet of the ejector, the gas storage is connected with a second inlet of the ejector through a first pipeline, an outlet of the ejector is connected with an inlet of the working medium condenser, an outlet of the working medium condenser is connected with an inlet of the liquid storage tank, the ejector mixes low-pressure working medium from the gas storage with high-pressure working medium compressed by the compression energy storage part to generate a working medium with adjustable pressure, and the working medium is condensed into liquid through the working medium condenser and is conveyed to the liquid storage tank. The working medium with adjustable pressure is generated by mixing high-pressure working medium and low-pressure working medium through the ejector, so that the pressure of mixed fluid at the outlet of the ejector can be controlled, the different energy storage pressure requirements of the system are met, and the application range of the system is enlarged.
Description
Technical Field
The invention relates to the technical field of energy storage, in particular to an energy storage system based on gas-liquid phase of working medium.
Background
The application of the energy storage technology can solve the defects of fluctuation, intermittence and the like of new energy power generation to a great extent, effectively solve the difficult problem of peak shifting and valley filling, and receive more and more attention in recent years. Among them, energy storage technologies based on gas-liquid phase transition of working media, such as carbon dioxide energy storage technologies, gradually draw attention due to advantages of simple structure, flexible arrangement, higher energy storage efficiency and the like. Chinese patent publication nos. CN112985143B, CN112985144B, CN112985145B and CN114109549B both disclose energy storage systems based on gas-liquid phase change of a working medium, and use carbon dioxide as the working medium, and the entire disclosures of which are incorporated herein by reference as part of the specification of the present patent application.
The variable energy storage pressure is a common operation mode of the energy storage system, but the traditional energy storage system based on the working medium gas-liquid phase change, such as a carbon dioxide energy storage system, can only enable the compressor to operate under variable working conditions, so that the compressor deviates from a working point of a performance curve, and the efficiency of the compressor is obviously reduced.
Disclosure of Invention
In order to overcome the technical defects in the prior art, the embodiment of the invention provides an energy storage system based on working medium gas-liquid phase combined with an ejector, the energy storage pressure of the energy storage system is variable, different energy storage pressure requirements can be met, and the application range of the system is further improved.
Specifically, the embodiment of the invention provides an energy storage system based on working medium gas-liquid phase, which comprises a gas storage warehouse, an energy storage component, an ejector and a liquid storage tank; the energy storage assembly comprises a compression energy storage part and a working medium condenser, wherein the gas storage is connected with a working medium inlet of the compression energy storage part, a working medium outlet of the compression energy storage part is connected with a first inlet of the ejector, the gas storage is connected with a second inlet of the ejector through a first pipeline, an outlet of the ejector is connected with an inlet of the working medium condenser, an outlet of the working medium condenser is connected with an inlet of the liquid storage tank, and the ejector mixes low-pressure working medium from the gas storage with high-pressure working medium compressed by the compression energy storage part to generate a working medium with adjustable pressure, and the working medium is condensed into liquid by the working medium condenser and conveyed to the liquid storage tank.
In one embodiment of the invention, the working medium outlet of the compression energy storage part is connected with the inlet of the working medium condenser through a second pipeline.
In one embodiment of the invention, the first conduit is provided with a first control valve and/or the second conduit is provided with a second control valve and/or a connecting conduit between the working medium outlet of the compression accumulator and the first inlet of the ejector is provided with a third control valve.
In one embodiment of the present invention, the energy storage system further includes an energy release assembly, the energy release assembly includes a working medium evaporator and an expansion energy release portion, an inlet of the working medium evaporator is connected to the outlet of the liquid storage tank, an outlet of the working medium evaporator is connected to a working medium inlet of the expansion energy release portion, and a working medium outlet of the expansion energy release portion is connected to the inlet of the liquid storage tank; the energy storage system further comprises a heat exchange assembly, the heat exchange assembly comprises a cold storage tank and a heat storage tank, the cold storage tank and the heat storage tank are used for containing heat storage media, and the cold storage tank and the heat storage tank are arranged between the compression energy storage part and the expansion energy release part so as to form a heat exchange loop between the compression energy storage part and the expansion energy release part.
In one embodiment of the invention, the energy storage system further comprises an organic rankine cycle subsystem, the organic rankine cycle subsystem comprises an inlet and an outlet, the inlet of the organic rankine cycle subsystem is connected with the working medium outlet of the expansion energy release portion, and the outlet of the organic rankine cycle subsystem is connected with the inlet of the gas storage.
In one embodiment of the invention, the energy storage system further comprises an organic rankine cycle subsystem comprising an inlet and an outlet, the inlet of the organic rankine cycle subsystem being connected to the expansion energy release portion and the outlet of the organic rankine cycle subsystem being connected to the inlet of the cold storage tank of the heat exchange assembly.
In one embodiment of the invention, the organic rankine cycle subsystem comprises an organic working medium expander, an organic working medium condenser, an organic working medium pump and an organic working medium evaporator, wherein the outlet of the organic working medium condenser is connected with the inlet of the organic working medium pump, the outlet of the organic working medium pump is connected with the first inlet of the organic working medium evaporator, the first outlet of the organic working medium evaporator is connected with the inlet of the organic working medium expander, the outlet of the organic working medium expander is connected with the inlet of the organic working medium condenser, the second inlet of the organic working medium evaporator is the inlet of the organic rankine cycle subsystem, and the second outlet of the organic working medium evaporator is the outlet of the organic rankine cycle subsystem.
In an embodiment of the present invention, the energy storage system further includes an organic rankine cycle subsystem, where the organic rankine cycle subsystem includes a first organic working medium expander, a second organic working medium expander, an organic working medium condenser, a first organic working medium pump, a first organic working medium evaporator, a second organic working medium pump and a second organic working medium evaporator, an outlet of the organic working medium condenser is connected to the inlet of the first organic working medium pump, an outlet of the first organic working medium pump is connected to a first inlet of the first organic working medium evaporator and an inlet of the second organic working medium pump, an outlet of the second organic working medium pump is connected to a first inlet of the second organic working medium evaporator, a first outlet of the second organic working medium evaporator is connected to the inlet of the second organic working medium expander, a first outlet of the first organic working medium evaporator is connected to an outlet of the second organic working medium evaporator, and an outlet of the second organic working medium evaporator is connected to the inlet of the second working medium evaporator.
In one embodiment of the invention, the expansion energy release part comprises at least one expansion energy release unit, each expansion energy release unit in the at least one energy release expansion unit comprises an energy release heat exchanger and a turbine, and a cold side inlet of the energy release heat exchanger is used as the working medium inlet of the expansion energy release part or is connected with an outlet of the turbine of the last expansion energy release unit; the cold side outlet of the energy release heat exchanger is connected with the inlet of the turbine; the outlet of the turbine is connected with the cold side inlet of an energy release heat exchanger of the next expansion energy release unit or the working medium outlet serving as the expansion energy release part; the hot side of the energy release heat exchanger is connected between the heat storage tank and the cold storage tank, and the hot side inlet of the energy release heat exchanger is connected with the outlet of the heat storage tank; the inlet of the organic Rankine cycle subsystem is connected with a hot side outlet of the energy release heat exchanger in at least one expansion energy release unit; and/or the compressed energy storage part comprises at least one compressed energy storage unit, each compressed energy storage unit in the at least one compressed energy storage unit comprises an energy storage heat exchanger and a compressor, and an inlet of the compressor is used as the working medium inlet of the compressed energy storage part or is connected with a hot side outlet of the energy storage heat exchanger of the last compressed energy storage unit; the outlet of the compressor is connected with the hot side inlet of the energy storage heat exchanger, and the hot side outlet of the energy storage heat exchanger is connected with the inlet of the compressor of the next compression energy storage unit or is used as the working medium outlet of the compression energy storage part; and a cold side inlet and a cold side outlet of the energy storage heat exchanger are respectively connected with the outlet of the cold storage tank and the inlet of the heat storage tank.
In one embodiment of the present invention, the working fluid is carbon dioxide.
In summary, the energy storage system based on the gas-liquid phase change of the working medium according to the embodiments of the present invention is provided with the first inlet of the ejector connected with the working medium outlet of the compressed energy storage portion, and the second inlet of the ejector connected with the gas storage reservoir, which can mix the high-pressure working medium and the low-pressure working medium (such as carbon dioxide) by using the ejector to generate the working medium with adjustable energy storage pressure, so that the magnitude of the energy storage pressure can be adjusted by the mass flow of the low-pressure fluid, which can ensure that the compressor always operates under the design working condition, provide the high-pressure working medium, and improve the safety and stability of the unit.
Secondly, through setting up control valve (first control valve, second control valve, third control valve) accessible regulation control valve's aperture control high, low pressure fluid proportion on corresponding pipeline, realize the accurate control to the mixed fluid pressure of sprayer export, satisfy energy storage system's different energy storage pressure demands, increased energy storage system's application scope.
Furthermore, the embodiment of the invention introduces the heat storage medium (such as carbon dioxide) at the working medium outlet of the heat exchange and/or expansion energy release part in the energy release process into the organic Rankine cycle subsystem, so that the gradient and high-efficiency utilization of the waste heat of the heat storage medium and/or working medium (such as carbon dioxide) in the energy release process can be realized, the output work of the energy release process of the system is effectively improved, and the energy storage efficiency is improved.
In addition, the embodiment of the invention controls the proportion of the organic working medium flowing into the first and second organic working medium evaporators by adjusting the opening degree of the fourth control valve, so that the full utilization of the heat storage medium and/or the working medium (such as carbon dioxide) waste heat of the energy storage system is realized, the low-grade heat utilization rate of the energy storage system is effectively improved, and the energy storage efficiency is further improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below; it is evident that the drawings in the following description are only some embodiments of the present invention and that other drawings may be obtained from these drawings without inventive effort for a person of ordinary skill in the art.
Fig. 1 is a schematic structural diagram of an energy storage system based on a working medium gas-liquid phase according to an embodiment of the present invention.
Fig. 2 is a schematic diagram of another structure of an energy storage system based on a gas-liquid phase of a working medium according to an embodiment of the present invention.
Fig. 3 is a schematic structural diagram of an energy storage system based on gas-liquid phase transition of a working medium according to an embodiment of the present invention.
Fig. 4 is a schematic structural diagram of an embodiment of the energy storage system based on the phase change of the working medium gas and liquid shown in fig. 3.
Fig. 5 is a schematic structural diagram of another embodiment of the energy storage system shown in fig. 3 based on a working medium gas-liquid phase.
Fig. 6 is a schematic diagram of another structure of an energy storage system based on a working medium gas-liquid phase according to an embodiment of the present invention.
Fig. 7 is a schematic diagram of another structure of an energy storage system based on a gas-liquid phase of a working medium according to an embodiment of the present invention.
Fig. 8 is a schematic diagram of another structure of an energy storage system based on a working medium gas-liquid phase according to an embodiment of the present invention.
Fig. 9 is a schematic diagram of another structure of an energy storage system based on a working medium gas-liquid phase according to an embodiment of the present invention.
Fig. 10 is a schematic structural diagram of an organic rankine cycle subsystem in an energy storage system based on a gas-liquid phase transition of a working medium according to an embodiment of the present invention.
Fig. 11 is a schematic structural diagram of another specific embodiment of an energy storage system based on a working medium gas-liquid phase according to an embodiment of the present invention.
The main reference symbols of the drawings indicate:
11. The gas storage, 12a, the compression energy storage part, 12b, the working medium condenser, 1201, the working medium inlet, 1202, the working medium outlet, 120a, the second control valve, 120b, the third control valve, 121, the compressor, 122, the energy storage heat exchanger, 123, the compressor, 124, the energy storage heat exchanger, 13, the liquid storage tank, 14, the energy release component, 14b, the working medium evaporator, 14a, the expansion energy release part, 1401, the working medium inlet, 1402, the working medium outlet, 140, the fifth control valve, 141, the energy release heat exchanger, 142, the turbine, 143, the energy release heat exchanger, 144, the turbine, 15, the ejector, 16, the first control valve, 17, the heat exchange component, 171, the cold storage tank, 172, the sixth control valve, 173, the heat storage tank, 174, the seventh control valve, 18, the organic Rankine cycle subsystem, 1801, the working medium inlet, 1802, the working medium outlet, 1803, the heat storage medium inlet, 1804, the heat storage medium outlet, 181': organic working medium expander 181, first organic working medium expander 182, second organic working medium expander 183, organic working medium condenser 184': organic working fluid pump 184, first organic working fluid pump 185': an organic working medium evaporator; 185. the first organic working medium evaporator, 186, the second organic working medium pump, 187, the second organic working medium evaporator, 188, the fourth control valve, 19, the preheater, 20 and the eighth control valve.
Detailed Description
In order that the above objects, features and advantages of the invention will be readily understood, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit of the invention, whereby the invention is not limited to the specific embodiments disclosed below.
In the description of the embodiments of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the embodiments of the present invention and simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.
Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.
In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.
In the present invention, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.
It will be understood that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.
Referring to fig. 1, an energy storage system 10, for example, a carbon dioxide energy storage system, based on a gas-liquid phase change of a working medium according to an embodiment of the present invention includes: a gas reservoir 11, a storage assembly, a reservoir 13 and an eductor 15. The energy storage component comprises a compression energy storage part 12a and a working medium condenser 12b, an outlet of the gas storage 11 is connected with a working medium inlet 1201 of the compression energy storage part 12a, a working medium outlet 1202 of the compression energy storage part 12a is connected with a first inlet (or called working fluid inlet) of the ejector 15, the gas storage 11 is connected with a second inlet (or called injection fluid inlet) of the ejector 15 through a first pipeline, an outlet of the ejector 15 is connected with an inlet of the working medium condenser 12b, and an outlet of the working medium condenser 12b is connected with an inlet of the liquid storage tank 13.
In some possible implementations, the gas reservoir 11 is a double-layered membrane structure including a mulching film, an inner membrane, and an outer membrane; the outer membrane is used for resisting wind and snow, an interlayer cavity is arranged between the inner membrane and the outer membrane, the outer membrane is upwards supported by gas in the interlayer cavity to keep the appearance, the gas storage 11 is not easy to collapse, the inner membrane and the mulching film form a containing cavity for storing gaseous carbon dioxide, and the pressure and the temperature in the inner membrane can be maintained within a certain range to meet the energy storage requirement. Illustratively, the pressure of the gaseous carbon dioxide within the gas reservoir 11 may be near ambient pressure, i.e., the surrounding atmospheric pressure. In some embodiments, the temperature within the gas reservoir 11 is in the range of-40 ℃ to 70 ℃, illustratively-40 ℃,0 ℃, 15 ℃, 20 ℃, 25 ℃, 30 ℃, 35 ℃, 40 ℃, 50 ℃, 60 ℃, 70 ℃, etc., and the pressure difference between the gas pressure within the gas reservoir 11 and the outside atmosphere is less than 1000Pa.
The pressure of the liquid carbon dioxide in the liquid storage tank 13 is between 2MPa and 10MPa, and is exemplified as 2MPa, 5MPa, 6MPa, 7MPa, 7.2MPa, 7.5MPa, 8MPa, 10MPa, etc. are optional.
Alternatively, the liquid carbon dioxide in the reservoir 13 may not exceed 50 ℃, in particular not exceed 30 ℃, for example between 20 ℃ and 30 ℃. Illustratively, the temperature of the liquid carbon dioxide flowing into the liquid storage tank 13 is 20-30 ℃ such that the temperature of the liquid carbon dioxide in the liquid storage tank 13 does not exceed 30 ℃.
Illustratively, the temperature of the liquid carbon dioxide in the liquid storage tank 13 is 20-30 ℃ and the pressure is between 7-7.5 MPa. In this way, potential safety hazards caused by accidental rising and pressure increase of liquid carbon dioxide in the liquid storage tank 13 can be avoided, so that the carbon dioxide energy storage system disclosed by the invention is more suitable for being deployed in places with dense personnel, such as residential areas, schools, hospitals, stations, commercial centers and the like.
The liquid storage tank 13 is used, for example, to store a liquid working medium or a gas-liquid mixed working medium such as liquid carbon dioxide or gas-liquid mixed carbon dioxide in a high-pressure state. The gas storage 11 is for example used for storing gaseous working medium such as gaseous carbon dioxide in a normal pressure state, and may be a gas film gas storage, the volume of which can be changed, when carbon dioxide is filled, the volume of the gas film gas storage increases, and when carbon dioxide flows out, the volume of the gas film gas storage decreases, so as to realize the constant pressure in the gas film gas storage. The gaseous working medium flowing out of the gas storage 11 is converted into a liquid working medium with pressure through the energy storage component, and finally flows into the liquid storage tank 13, and energy storage is completed in the process. The compression energy storage part 12a is used for compressing the low-pressure working medium of the gas storage 11 into a high-pressure working medium. Here, "low pressure" and "high pressure" are in a state opposite to each other, that is, the pressure of the working medium compressed by the compression accumulator 12a is higher than the pressure of the working medium stored in the gas reservoir 11. The ejector 15 mixes the low-pressure working medium from the gas storage 11 and the high-pressure working medium compressed by the compression energy storage 12a to generate a working medium with adjustable energy storage pressure, and the working medium is condensed into a liquid state by the working medium condenser 12b and is delivered to the liquid storage tank 13.
According to the energy storage system 10 based on the working medium gas-liquid phase change, the ejector 15 is arranged, high-pressure working medium (such as carbon dioxide) and low-pressure working medium (such as carbon dioxide) can be mixed by the ejector 15, the compressor in the compression energy storage part always operates under the design working condition, the mass flow of the output high-pressure fluid is kept unchanged, the energy storage pressure can be regulated through the mass flow of the low-pressure fluid, the compressor in the compression energy storage part can be ensured to always operate under the design working condition, and the safety and stability of the unit are improved.
Referring to fig. 2, in some embodiments, working substance outlet 1202 of compression accumulator 12a is connected to the inlet of working substance condenser 12b by a second conduit. By arranging the second pipeline, the requirement that the energy storage pressure required by a user is equal to the design energy storage pressure can be met, so that working media from the gas storage can be mixed without the ejector 15 in the energy storage process, are compressed into high-pressure working media by the compressed energy storage part 12a, and the pressure loss caused by the ejector 15 can be reduced, so that the higher energy storage pressure of the energy storage system 10 can be reserved.
With continued reference to fig. 2, control valves may be provided on the respective lines to effect adjustment of the mixing ratio of the working medium. For example, a first control valve 16 is provided on the first conduit. The magnitude of the flow rate of the low-pressure working medium sucked by the ejector 15 can be controlled by adjusting the opening degree of the first control valve 16. The opening degree of the first control valve 16 becomes large, the flow amount of the low-pressure working medium inhalable by the ejector 15 becomes large, and the achievable storage pressure becomes small. The opening degree of the first control valve 16 becomes smaller, the flow rate of the low-pressure working medium sucked by the ejector 15 becomes smaller, and the achievable storage pressure becomes larger. Therefore, the first control valve 16 can control the ratio of high-pressure fluid to low-pressure fluid, so that the control of the pressure of the mixed fluid at the outlet of the ejector 15 is realized, the different energy storage pressure requirements of the system are met, and the application range of the system is enlarged.
For example, a third control valve 120b is disposed on a connecting pipeline between the working medium outlet 1202 of the energy storage compression portion 12a and the first inlet of the ejector 15, so as to control the flow rate of the high-pressure working medium flowing through the ejector 15 within a design flow rate range, and ensure that the mass flow rate of the high-pressure fluid output by the energy storage compression portion 12a is kept unchanged, so that the compressor always operates under the design working condition. When the second pipeline is provided, the third control valve 120b and the first control valve 16 can be completely closed, so that the high-pressure working medium can flow to the working medium condenser 12b through the second pipeline completely, the low-pressure working medium is not mixed, and the available energy storage pressure reaches the design energy storage pressure.
For example, a second control valve 120a is provided in the second pipe. The second control valve 120a is opened (the third control valve 120b and the first control valve 16 are closed), and the flow rate of the working medium flowing through the compression energy storage portion 12a is controlled within the design flow rate range, so that the working medium entering the working medium condenser 12b is the high-pressure working medium compressed by the compression energy storage portion 12a, and the available energy storage pressure at this time is the design pressure. Closing the second control valve 120a (opening the third control valve 120b and adjusting the first control valve 16), the working fluid entering the working fluid condenser 12b is the working fluid with adjustable pressure after being mixed by the ejector 15, and the available storage pressure is lower than the design pressure. The stored energy pressure may be selected between a design pressure and below the design pressure.
In some embodiments, one or more of the first control valve 16, the second control valve 120a, and the third control valve 120b may be selectively set according to actual requirements, for example, when the second pipe is provided, the stored energy pressure may be selected to be the design pressure or lower than the design pressure by opening and closing the second control valve 120a, for example, when the second pipe is not provided, and no second control valve 120a is provided, and the available stored energy pressure is lower than the design pressure. The opening degree of the first control valve 16 is adjustable. For example, when the stored energy pressure required by the user is lower than the design stored energy pressure, the second control valve 120a may be closed and the third control valve 120b may be opened; the high-low pressure fluid mixing ratio is adjusted by adjusting the opening degree of the first control valve 16. Conversely, when the desired accumulator pressure is equal to the design accumulator pressure, the first control valve 16, the third control valve 120b, and the second control valve 120a may be closed.
In some embodiments, fig. 3 further includes an energy release assembly 14, where the liquid working medium flowing from the liquid storage tank 13 is converted into gaseous expansion to perform work or generate electricity by the energy release assembly 14, and flows into the gas storage 11, and during this process, the energy stored in the energy storage process is released. The energy release assembly 14 includes a working substance evaporator 14b and an expansion energy release portion 14a. An inlet of the working medium evaporator 14b is connected with the outlet of the liquid storage tank 13, an outlet of the working medium evaporator 14b is connected with a working medium inlet 1401 of the expansion energy release part 14a, and a working medium outlet 1402 of the expansion energy release part 14a is connected with the inlet of the gas storage 11. Furthermore, the energy storage system 10 further comprises a heat exchange assembly 17, and the heat exchange assembly 17 comprises a cold storage tank 171 and a heat storage tank 173. The heat storage tanks 171 and 173 are used for containing a heat storage medium, such as heat transfer oil, molten salt, or saturated water. The working substance evaporator 14a is used for evaporating the liquid working substance and converting the liquid working substance into a gaseous working substance. The expansion energy release part 14a utilizes high-temperature gaseous working medium to expand to do work or generate electricity to realize energy output.
Referring to fig. 4 and 5, a cold storage tank 171 and a heat storage tank 173 are disposed between the compression energy storage portion 12a and the expansion energy release portion 14a to form a heat exchange circuit between the compression energy storage portion 12a and the expansion energy release portion 14 a. During the process of energy storage and release, the heat storage medium circularly flows between the energy storage cold tank 171 and the heat storage tank 173, so that temporary storage and release of energy are realized. Specifically, the energy is temporarily stored in the heat storage medium in the form of heat. During the energy storage process, the low-temperature heat storage medium flows from the cold storage tank 171 to the compression energy storage portion 12a, and absorbs heat in the compressed high-temperature working medium to raise the temperature of the heat storage medium. The warmed high-temperature heat storage medium flows to the heat storage tank 173, and the heat is temporarily stored in the heat storage tank 173. When energy is released, the high-temperature heat storage medium flows from the heat storage tank 173 to the expansion energy release portion 14a, and transfers heat to the working medium flowing through the expansion energy release portion 14a, so that the temperature thereof is increased. After the heat exchange is completed, the temperature of the heat storage medium is lowered, and the cooled heat storage medium flows to the cold storage tank 171.
Further, in some embodiments, the energy storage system 10 based on a phase change of the working fluid gas-liquid further includes an organic rankine cycle subsystem 18. The orc subsystem 18 includes an inlet and an outlet.
Referring to fig. 6, in some embodiments, the inlet of the organic rankine cycle subsystem 18 is connected to the working medium outlet 1402 of the expansion energy release portion 14a, and the outlet of the organic rankine cycle subsystem 18 is connected to the inlet of the gas reservoir 11. The waste heat of the expanded working medium can be absorbed between the working medium outlet 1402 of the expansion energy release part 14a and the inlet of the gas storage 11 of the organic Rankine cycle subsystem 18, so that the full utilization of the waste heat of the carbon dioxide working medium is realized. Of course, in this embodiment, a directly connected pipeline may be further disposed between the working medium outlet 1402 of the expansion energy release portion 14a and the inlet of the gas storage 11, a control valve is disposed on the pipeline, and a control valve is disposed between the working medium outlet 1402 of the expansion energy release portion 14a and the inlet of the organic rankine cycle subsystem 18, so that the working medium outlet 1402 of the expansion energy release portion 14a can be selectively communicated with the organic rankine cycle subsystem 18 or the gas storage 11 through the two control valves, and whether the residual heat of the carbon dioxide working medium is utilized is selected through the two control valves, so that the operation of the energy storage system is more flexible.
Referring to fig. 7, in some embodiments, an inlet of the organic rankine cycle subsystem 18 is connected to the expansion energy release portion 14a, and an outlet of the organic rankine cycle subsystem 18 is connected to an inlet of the cold storage tank 171 of the heat exchange assembly 17. The waste heat of the heat storage medium in the energy release process can be absorbed through the organic Rankine cycle subsystem 18 connected between the expansion energy release part 14a and the inlet of the cold storage tank 171 of the gas storage 11, so that the full utilization of the waste heat of the heat storage medium is realized. Of course, in this embodiment, a directly connected pipe may be provided at the inlet of the expansion energy release portion 14a and the cold storage tank 171, and a control valve may be provided on the pipe, and a control valve may also be provided on the pipe between the expansion energy release portion 14a and the inlet of the organic rankine cycle subsystem 18, through which the heat storage medium of the expansion energy release portion 14a may be selectively connected to the cold storage tank 171 or the organic rankine cycle subsystem 18. And whether the waste heat of the heat storage medium is utilized or not is selected through the two control valves, so that the energy storage system is more flexible to operate.
In some embodiments, the outlet of the orc subsystem 18 is connected to a cooler to achieve further cooling of the thermal storage medium. The cooled heat storage medium flows to the energy storage component to absorb heat sufficiently to generate power by the next organic Rankine cycle. Further, the outlet of the orc subsystem 18 may also be re-connected to the inlet of the cold storage tank 171 through a chiller or directly connected to the inlet of the cold storage tank 171. The heat storage medium at the outlet of the organic Rankine cycle subsystem 18 is further cooled by a cooler and stored in the cold storage tank 171, so that the temperature requirement of the cold storage tank 171 is reduced, and the manufacturing cost of the cold storage tank 171 is reduced. For energy storage and energy release intermittent, the heat storage medium at the outlet of the organic Rankine cycle subsystem 18 can be stored after being buffered or temporarily stored in the cold storage tank 171, and when the energy storage component works, the heat storage medium flows to the energy storage component to perform the next organic Rankine cycle power generation.
In some embodiments, the outlet of the orc subsystem 18 is connected to the evaporator 14b. Further, the outlet of the orc subsystem 18 may be re-connected to the inlet of the cold storage tank 171 via the evaporator 14b. The heat storage medium is cooled further, the next organic Rankine cycle is facilitated, and the waste heat of the heat storage medium is used for the evaporator 14b. The heat storage medium exiting the orc subsystem 18 provides heat storage medium directly to the evaporator 14b to evaporate the liquid phase carbon dioxide flowing through the evaporator 14b. After the heat storage medium is cooled by the evaporator 14b, the heat storage medium can directly flow to the energy storage component to absorb heat for the next organic Rankine cycle power generation; the energy storage and energy release intermittent type formula can also store after the cold storage jar 171 buffering or temporary storage, and the energy storage subassembly during operation flows to the energy storage subassembly and carries out the organic Rankine cycle electricity generation next time.
Of course, in some embodiments, an organic Rankine cycle subsystem 18 may be alternatively or additionally disposed between the working fluid outlet 1402 of the expansion and energy release portion 14a and the inlet of the gas reservoir 11, and between the expansion and energy release portion 14a and the inlet of the cold storage tank 171.
Specifically, referring to fig. 8, one organic rankine cycle subsystem 18 is connected between the working medium outlet 1402 of the expansion energy release portion 14a and the inlet of the gas storage 11, and the other organic rankine cycle subsystem 18 is connected between the expansion energy release portion 14a and the inlet of the cold storage tank 171. Each organic rankine cycle subsystem 18, for example, includes an organic working medium expander 181', an organic working medium condenser 183, an organic working medium pump 184', and an organic working medium evaporator 185', wherein an outlet of the organic working medium condenser 183 is connected to an inlet of the organic working medium pump 184', an outlet of the organic working medium pump 184' is connected to a first inlet of the organic working medium evaporator 185', a first outlet of the organic working medium evaporator 185' is connected to an inlet of the organic working medium expander 181', an outlet of the organic working medium expander 181' is connected to an inlet of the organic working medium condenser 183, a second inlet of the organic working medium evaporator 185' is an inlet of the organic rankine cycle subsystem, and a second outlet of the organic working medium evaporator 185' is an outlet of the organic rankine cycle subsystem 18.
Namely, in the energy storage system shown in fig. 6, and in one organic rankine cycle subsystem 18 connected between the working medium outlet 1402 of the energy release expansion portion 14a and the inlet of the gas storage 11 in fig. 8, the second inlet of the organic working medium evaporator 185 'is connected to the working medium outlet 1402 of the expansion energy release portion 14a, and the second outlet of the organic working medium evaporator 185' is connected to the inlet of the gas storage 11.
In the energy storage system shown in fig. 7, and in the other organic rankine cycle subsystem 18 connected between the energy release expansion portion 14a and the cold storage tank 171 in fig. 8, the second inlet of the organic working fluid evaporator 185 'is connected to the expansion energy release portion 14a, and the second outlet of the organic working fluid evaporator 185' is connected to the outlet of the cold storage tank 171.
Or in some embodiments, the inlet of the organic rankine cycle subsystem 18 as shown in fig. 9 includes a working medium inlet 1801 and a heat storage medium inlet 1803, the outlet of the organic rankine cycle subsystem 18 includes a working medium outlet 1802 and a heat storage medium outlet 1804, the working medium inlet 1801 of the organic rankine cycle subsystem 18 is connected to the working medium outlet 1402 of the expansion energy release portion 14a, the working medium outlet 1802 of the organic rankine cycle subsystem 18 is connected to the inlet of the gas storage 11, the heat storage medium inlet 1803 of the organic rankine cycle subsystem 18 is connected to the expansion energy release portion 14a, and the heat storage medium outlet 1804 of the organic rankine cycle subsystem 18 is connected to the inlet of the cold storage tank 171 of the heat exchange assembly 17. By the arrangement of the organic Rankine cycle subsystem 18, the waste heat of the heat storage medium in the energy release process and the waste heat of the expanded working medium can be absorbed, so that the full utilization of the carbon dioxide working medium and the waste heat of the heat storage medium is realized.
More specifically, referring to fig. 10 and 11, in some embodiments, the organic rankine cycle subsystem 18 is, for example, a dual-stage organic rankine cycle subsystem including, for example, a first organic working medium expander 181 and a second organic working medium expander 182, an organic working medium condenser 183, a first organic working medium pump 184 and a second organic working medium pump 186, and a first organic working medium evaporator 185 and a second organic working medium evaporator 187. An outlet of the organic working medium condenser 183 is connected with an inlet of the first organic working medium pump 184, an outlet of the first organic working medium pump 184 is connected with a first inlet of the first organic working medium evaporator 185 and an inlet of the second organic working medium pump 186, an outlet of the second organic working medium pump 186 is connected with a first inlet of the second organic working medium evaporator 187, a first outlet of the second organic working medium evaporator 187 is connected with an inlet of the second organic working medium expander 182, a first outlet of the first organic working medium evaporator 185 and an outlet of the second organic working medium expander 182 are jointly connected with an inlet of the first organic working medium expander 181, an outlet of the first organic working medium expander 181 is connected with an inlet of the organic working medium condenser 183, The second inlet of the first organic working medium evaporator 185 is a working medium inlet 1801 of the organic Rankine cycle subsystem 18 and is connected with a working medium outlet 1402 of the energy release expansion part 14 a; The second outlet of the first organic working medium evaporator 185 is a working medium outlet 1802 of the organic Rankine cycle subsystem 18 and is connected with the inlet of the gas storage 11; the second inlet of the second organic working medium evaporator 187 is a heat storage medium inlet 1803 of the organic Rankine cycle subsystem 18, and is connected with the energy release expansion part 14a; the second outlet of the second organic working medium evaporator 187 is the heat storage medium outlet 1804 of the organic rankine cycle subsystem 18, and is connected to the inlet of the cold storage tank 171. In this embodiment, by providing a two-stage organic rankine cycle subsystem as a specific way of the organic rankine cycle subsystem 18, more efficient and sufficient waste heat utilization can be achieved. in addition, as a specific embodiment of the organic rankine cycle subsystem 18, the two-stage organic rankine cycle subsystem uses an organic working medium selected from cyclopropane, butane, R152a (i.e., 1-difluoroethane) and the like, so as to meet the evaporation temperature requirement. Because the temperature of the heat source (heat storage medium) flowing into the second organic working medium evaporator 187 is higher than the temperature of the heat source (carbon dioxide) flowing into the first organic working medium evaporator 185, in order to improve the power generation efficiency of the organic rankine cycle power generation assembly, the liquid-phase organic working medium is pressurized by the first organic working medium pump 184, a part of the pressurized liquid-phase organic working medium flows into the first organic working medium evaporator 185 to evaporate, and the other part flows into the second organic working medium evaporator 187 to evaporate after being further pressurized by the second organic working medium pump 186, so that different evaporation pressures and different evaporation temperatures of the liquid-phase organic working medium in the second organic working medium evaporator 187 and the first organic working medium evaporator 185 are realized, The heat energy and the carbon dioxide heat energy of the heat storage media with different temperatures are converted into the pressure energy with different organic working media, so that the first organic working medium expander 181 and the second organic working medium expander 182 generate power, and the pressure energy with different organic working media is maximally converted into electric energy.
In some embodiments, such as shown in fig. 10, the organic rankine cycle subsystem 18 also includes a fourth control valve 188, such that the outlet of the first organic working fluid pump 184 is connected to the first inlet of the first organic working fluid evaporator 185 through the fourth control valve 188. Further, the opening degree of the fourth control valve 188 is adjustable. Therefore, the opening degree of the fourth control valve 188 can be controlled, the organic working medium ratio entering the first organic working medium evaporator 185 and the second organic working medium evaporator 187 can be adjusted, and the full utilization of the residual heat of the carbon dioxide working medium and the heat storage medium can be realized.
In some embodiments, the expansion energy releasing portion 14a includes at least one expansion energy releasing unit, and when the number of expansion energy releasing units is more than one, the more than one expansion energy releasing units are connected in sequence. Each of the at least one expansion energy releasing unit comprises an energy releasing heat exchanger and a turbine, wherein the cold side inlet of the energy releasing heat exchanger is used as a working medium inlet 1401 of the expansion energy releasing part 14a or is connected with the outlet of the turbine of the last expansion energy releasing unit. The cold side outlet of the energy release heat exchanger is connected with the inlet of the turbine. The outlet of the turbine is connected with the cold side inlet of the energy release heat exchanger of the next expansion energy release unit or used as a working medium outlet 1402 of the expansion energy release part 14 a. The hot side of the energy release heat exchanger is connected between the heat storage tank 173 and the cold storage tank 171, and the hot side inlet of the energy release heat exchanger is connected to the outlet of the heat storage tank 173. Referring to fig. 4 for example, the expansion energy releasing portion 14a has one expansion energy releasing unit (single stage) including an energy releasing heat exchanger 141 and a turbine 142. The cold side inlet of the energy release heat exchanger 141 is used as a working medium inlet 1401 of the expansion energy release part 14a, the inlet of the turbine 142 is connected with the cold side outlet of the energy release heat exchanger 141, the outlet of the turbine 142 is used as a working medium outlet 1402 of the expansion energy release part 14a, and the hot side inlet and the hot side outlet of the energy release heat exchanger 141 are respectively connected with the outlet of the heat storage tank 173 and the inlet of the cold storage tank 171. The turbine 142 is used for driving the generator to generate power, the liquid-phase working medium stored in the liquid storage tank 13 flows through the evaporator 14b to evaporate the working medium under the gas phase high-pressure state, such as high-pressure carbon dioxide, and expands in the corresponding turbine 142 after heat exchange and temperature rise of the high-pressure carbon dioxide through the energy release heat exchanger 141, so that the pressure energy and the heat energy are released together, and the mechanical energy is converted.
Alternatively, referring to fig. 5, the expansion energy releasing portion 14a has two expansion energy releasing units (multi-stage), one including an energy releasing heat exchanger 141 and a turbine 142, and the other including an energy releasing heat exchanger 143 and a turbine 144. The cold side inlet of the energy release heat exchanger 141 is used as a working medium inlet 1401 of the expansion energy release part 14a, the inlet of the turbine 142 is connected with the cold side outlet of the energy release heat exchanger 141, and the outlet of the turbine 142 is connected with the cold side inlet of the energy release heat exchanger 143. The cold side outlet of the energy release heat exchanger 143 is connected to the inlet of the turbine 144, and the outlet of the turbine 144 serves as the working medium outlet 1402 of the expansion energy release portion 14 a. The hot side inlet and hot side outlet of the energy release heat exchanger 141 are connected to the outlet of the heat storage tank 173 and the inlet of the cold storage tank 171, respectively. The hot side inlet and hot side outlet of the energy release heat exchanger 143 are connected to the outlet of the heat storage tank 173 and the inlet of the cold storage tank 171, respectively. The turbines 142 and 144 are respectively used for driving the generator to generate electricity, the liquid phase working medium stored in the liquid storage tank 13 flows through the gas phase evaporated by the evaporator 14b and is in a high pressure state, for example, high pressure carbon dioxide is subjected to heat exchange and temperature rise through the energy release heat exchanger 141 and the energy release heat exchanger 143, and then the corresponding turbines 142 and 144 are expanded to release the pressure energy and the heat energy together and convert the pressure energy and the heat energy into mechanical energy. Of course, the present embodiment does not limit the number of stages of the expansion energy releasing unit.
When the organic rankine cycle subsystem 18 is provided according to the foregoing embodiment, referring to fig. 6 and 8, the inlet of the organic rankine cycle subsystem 18 (which may also be the heat storage medium inlet 1803 of the organic rankine cycle subsystem 18 shown in fig. 9 to 11) connected between the energy release expansion portion 14a and the inlet of the accumulator 171 is connected to the hot side outlet of the energy release heat exchanger of at least one expansion energy release unit. For example, in fig. 11, the expansion energy release portion 14a includes a two-stage expansion energy release unit, and the heat storage medium inlet 1803 of the orc subsystem 18 may be connected to the hot side outlet of the energy release heat exchanger 143. Specifically, the heat storage medium flowing out of the hot side outlet of the energy release heat exchanger 143 flows through the second organic working medium evaporator 187 via the heat storage medium inlet 1803, and flows out of the heat storage medium outlet 1804 to the cold storage tank 171. Thus, the waste heat after the expansion of the energy release expansion part 14 can be fully recovered. Or the thermal storage medium inlet 1803 of the orc subsystem 18 may also be connected to the hot side outlet (not shown) of the energy release heat exchanger 141. In some embodiments, the heat storage medium inlet of the organic rankine cycle subsystem 18 and the hot side outlet of each energy release heat exchanger may be respectively connected (not shown), optionally, a control valve is disposed on each connecting pipeline, and the hot side outlet of the designated energy release heat exchanger is selectively connected with the organic rankine cycle subsystem 18 through opening and closing of the control valve. Wherein, a direct connection pipeline can be arranged between the hot side outlet of each energy release heat exchanger and the inlet of the cold storage tank 171, and the control valve is used for selecting whether the heat storage medium of the hot side outlet directly enters the cold storage tank 171 without passing through the organic Rankine cycle subsystem 18. The energy storage system is flexible and adjustable, and the selectivity is more.
In some embodiments, the compressed energy storage 12a includes at least one compressed energy storage unit, and when the compressed energy storage unit is more than one, the more than one compressed energy storage units are connected in sequence. Each of the at least one compressed energy storage unit includes an energy storage heat exchanger and a compressor. The inlet of the compressor serves as the working medium inlet 1201 of the compressed energy storage 12a or as the hot side outlet of the energy storage heat exchanger connected to the previous compressed energy storage unit. The outlet of the compressor is connected with the hot side inlet of the energy storage heat exchanger, and the hot side outlet of the energy storage heat exchanger is connected with the inlet of the compressor of the next compression energy storage unit or used as the working medium outlet 1202 of the compression energy storage part 12 a. The cold side inlet and the cold side outlet of the energy storage heat exchanger are connected to the outlet of the cold storage tank 171 and the inlet of the heat storage tank 173, respectively.
As shown in fig. 4 in particular, the compressed energy storage section 12a includes one compressed energy storage unit (single stage) including a compressor 121 and an energy storage heat exchanger 122. The inlet of the compressor 121 serves as a working medium inlet 1201 of the compressed energy storage 12a, the hot side inlet of the energy storage heat exchanger 122 is connected to the outlet of the compressor 121, and the hot side outlet of the energy storage heat exchanger 122 serves as a working medium outlet 1202 of the compressed energy storage 12 a. The cold side inlet and the cold side outlet of the energy storage heat exchanger 122 are connected to the outlet of the cold storage tank 171 and the inlet of the heat storage tank 173, respectively. The compressor 121 is driven by a motor, a part of the input electric energy is stored in a working medium under a high pressure state, such as high-pressure carbon dioxide, and enters the liquid storage tank 13, and a part of the electric energy is transferred and stored in a heat energy form to the heat storage tank 173 through the cold side of the energy storage heat exchanger 122; i.e. during the energy storage process, the input electrical energy is stored in the form of pressure energy and thermal energy.
Alternatively, referring to fig. 5, the compressed energy storage portion 12a includes two compressed energy storage units (multi-stages). One compression energy storage unit comprises a compressor 121 and an energy storage heat exchanger 122. The other compression energy storage unit comprises a compressor 123 and an energy storage heat exchanger 124. The inlet of the compressor 121 is used as a working medium inlet 1201 of the compressed energy storage part 12a, the hot side inlet and the hot side outlet of the energy storage heat exchanger 122 are respectively connected with the outlet of the compressor 121 and the inlet of the compressor 123, the outlet of the compressor 123 is connected with the hot side inlet of the energy storage heat exchanger 124, the hot side outlet of the energy storage heat exchanger 124 is used as a working medium outlet 1202 of the compressed energy storage part 12a, the cold side inlet and the cold side outlet of the energy storage heat exchanger 122 are respectively connected with the outlet of the cold storage tank 171 and the inlet of the heat storage tank 173, and the cold side inlet and the cold side outlet of the energy storage heat exchanger 124 are respectively connected with the outlet of the cold storage tank 171 and the inlet of the heat storage tank 173. The compressors 121 and 123 are driven by, for example, motors, and a part of the input electric energy is stored in a working medium such as high-pressure carbon dioxide in a high-pressure state in a pressure energy form and enters the liquid storage tank 13, and a part of the electric energy is transferred and stored in a heat energy form to the heat storage tank 173 through the cold sides of the energy storage heat exchanger 122 and the energy storage heat exchanger 124, respectively; i.e. during the energy storage process, the input electrical energy is stored in the form of pressure energy and thermal energy. Of course, the present embodiment does not limit the number of compressed energy storage units.
Referring to fig. 4 and 5, in some embodiments, the class of energy storage systems 10 based on a phase change of the working fluid gas-liquid further comprises a pre-heater 19, whereby the working fluid inlet 1201 of the compressed energy storage section 12a is connected to the outlet of the gas reservoir 11 via the pre-heater 19. In addition, a pipeline member such as a control valve 20 is provided between the preheater 19 and the air reservoir 11. The industrial cooling water is returned to the working medium evaporator 14b to provide heat for the evaporation of the carbon dioxide working medium.
In order to more clearly understand the working medium gas-liquid phase change based energy storage system 10 according to the embodiment of the present invention, an operation method of the working medium gas-liquid phase change based energy storage system 10 will be described in detail below with reference to fig. 11 by taking carbon dioxide as a gas-liquid phase change working medium (i.e. working medium), and specifically may include the following steps:
In the initial state, all eight control valves (an eighth control valve 20, a sixth control valve 172, a seventh control valve 174, a first control valve 16, a second control valve 120a, a third control valve 120b, a fifth control valve 140 and a fourth control valve 188) are closed, and the gas storage 11 stores normal-temperature and normal-pressure carbon dioxide gas as a working medium;
When the user is in the low electricity consumption range, if the energy storage pressure required by the user is equal to the design energy storage pressure, the first control valve 16, the third control valve 120b, the fifth control valve 140, the seventh control valve 174 and the fourth control valve 188 are closed, the eighth control valve 20, the sixth control valve 172 and the second control valve 120a are opened, and the energy storage part of the energy storage system 10 works. Specifically, carbon dioxide at normal temperature and normal pressure enters the compressor 121 after being heated by heat absorption of the preheater 19 from the gas storage 11, after the carbon dioxide is compressed by the compressor 121 driven by the electric motor, the carbon dioxide enters the energy storage heat exchanger 122 to exchange heat and cool, heat is transferred to a part of low-temperature heat storage medium flowing out of the cold storage tank 171, cooled medium-pressure carbon dioxide enters the compressor 123, the carbon dioxide is compressed to a given pressure by the electric motor driven by the compressor 123, high-temperature high-pressure carbon dioxide subsequently enters the energy storage heat exchanger 124 to exchange heat and cool, heat is transferred to the rest low-temperature heat storage medium flowing out of the cold storage tank 171, cooled high-pressure carbon dioxide enters the working medium condenser 12b to be condensed into a liquid state and then stored in the liquid storage tank 13. The heat storage mediums which are subjected to heat absorption and temperature rise through the two energy storage heat exchangers 122 and 124 are mixed and stored in the heat storage tank 173 together. The compression, storage and heat storage of the carbon dioxide working medium are completed.
When the stored energy pressure required by the user is lower than the designed stored energy pressure, the second control valve 120a, the fifth control valve 140, the seventh control valve 174 and the fourth control valve 188 are closed, the eighth control valve 20, the sixth control valve 172, the first control valve 16 and the third control valve 120b are opened, and the stored energy portion of the energy storage system 10 operates. Specifically, the normal temperature and pressure carbon dioxide flowing out of the gas storage 11 is divided into two paths, one path enters the ejector 15 through the first control valve 16, the other path enters the compressor 121 after absorbing heat and heating through the preheater 19, electric power drives the compressor 121 to compress the carbon dioxide through the motor, the carbon dioxide enters the energy storage heat exchanger 122 to exchange heat and cool down, heat is transferred to a part of low-temperature heat storage medium flowing out of the cold storage tank 171, cooled medium-pressure carbon dioxide enters the compressor 123, electric power drives the compressor 123 to compress the carbon dioxide to the designed energy storage pressure through the motor, high-temperature and high-pressure carbon dioxide subsequently enters the energy storage heat exchanger 124 to exchange heat and cool down, heat is transferred to the rest low-temperature heat storage medium flowing out of the cold storage tank 171, cooled high-pressure carbon dioxide enters the ejector 15 to be mixed with normal pressure carbon dioxide and then injected, all carbon dioxide flows into the working medium condenser 12b to be condensed into liquid state and then stored in the liquid storage tank 13. The heat storage mediums which are subjected to heat absorption and temperature rise through the two energy storage heat exchangers 122 and 124 are mixed and stored in the heat storage tank 173 together. Thus, the compression, storage and heat storage of the working medium are completed.
Preferably, the opening degree of the first control valve 16 can be adjusted to control the proportion of the high-pressure carbon dioxide fluid and the low-pressure carbon dioxide fluid, so that the flexible adjustment of the energy storage pressure of the system is realized.
When the user is at the peak of electricity consumption, the eighth control valve 20, the sixth control valve 172, the first control valve 16, the second control valve 120a and the third control valve 120b are closed, the fifth control valve 140, the seventh control valve 174 and the fourth control valve 188 are opened, and the energy release portion of the energy storage system 10 is operated. Specifically, the liquid carbon dioxide in the liquid storage tank 13 enters the working medium evaporator 14b to absorb heat and evaporate into saturated gas, then enters the energy release heat exchanger 141 to exchange heat with part of the heat storage medium flowing out of the heat storage tank 173, and the high-temperature and high-pressure carbon dioxide enters the turbine 142 to expand and do work and drive the generator to generate electricity. The expanded medium-temperature and medium-pressure carbon dioxide enters the energy release heat exchanger 143 to exchange heat with the rest part of heat storage medium flowing out of the heat storage tank 173, and the high-temperature and medium-pressure carbon dioxide enters the turbine 144 to continuously expand and work to normal pressure, and drives the generator to generate electricity. Finally, the atmospheric carbon dioxide enters the first organic working medium evaporator 185, exchanges heat and cools to normal temperature and pressure, and is stored in the gas storage 11. One path of heat storage medium flowing out of the heat storage tank 173 is subjected to heat release and temperature reduction through the energy release heat exchanger 143, enters the second organic working medium evaporator 187 to continuously release heat and temperature reduction, is mixed with the other path of heat storage medium subjected to heat release and temperature reduction through the energy release heat exchanger 141, and enters the cold storage tank 171 for storage. Thus, the expansion work of carbon dioxide and the heat release are completed. It can be understood that after the heat storage medium flowing out from the heat storage tank 173 is released and cooled by the energy release heat exchanger 141, the heat storage medium enters the second organic working medium evaporator 187 to continuously release and cool, and then is mixed with the heat storage medium released and cooled by the energy release heat exchanger 143, and enters the cold storage tank 171 for storage. Or the heat storage medium flowing out of the heat storage tank 173 is respectively discharged and cooled by the energy release heat exchanger 143, and then enters the second organic working medium evaporator 187 to continuously discharge heat and cool, and then enters the cold storage tank 171 for storage.
The two-stage organic Rankine cycle subsystem and the energy release part work simultaneously: after being compressed by a first organic working medium pump 184, part of the organic working medium enters a first organic working medium evaporator 185, absorbs the carbon dioxide heat at normal pressure and medium temperature to evaporate into a gaseous state, and after being recompressed by a second organic working medium pump 186, enters the second organic working medium evaporator 187, absorbs the heat of a medium temperature heat storage medium to evaporate into a gaseous state, and enters the second organic working medium expander 182 for expanding and working into a medium temperature and medium pressure gaseous state organic working medium to drive a generator to generate power, and then is mixed with the medium temperature and medium pressure gaseous state organic working medium at the outlet of the first organic working medium evaporator 185, and then enters the first organic working medium expander 181 together to continuously expand and work into a low temperature and low pressure organic working medium to drive the generator to generate power; finally, the low-temperature low-pressure gaseous organic working medium enters the organic working medium condenser 183 to be subjected to exothermic condensation into a liquid state, so that circulation and additional power output are completed. Because the temperature of the heat source (heat storage medium) flowing into the second organic working medium evaporator 187 is higher than the temperature of the heat source (carbon dioxide) flowing into the first organic working medium evaporator 185, the liquid organic working medium is converted into organic working medium with different pressure energy by the first organic working medium pump 184 and the second organic working medium pump 186 so as to absorb the heat of the heat storage medium and the carbon dioxide with different temperatures, and the first organic working medium expander 181 and the second organic working medium expander 182 expand and do work to generate electricity, so that the different pressure energy of the organic working medium is maximally converted into electric energy to be output.
Preferably, as shown in fig. 11, the opening of the fourth control valve 188 can be controlled according to the flow rate and the temperature of the carbon dioxide at the outlet of the turbine 144 and the flow rate and the temperature of the heat storage medium at the hot side outlet of the energy release heat exchanger 143, so as to adjust the proportion of the organic working medium entering the first organic working medium evaporator 185 and the second organic working medium evaporator 187, thereby realizing the full utilization of the waste heat of the carbon dioxide and the heat storage medium.
From the above, the control method of the embodiment of the present invention may be implemented: the energy is stored by using the low-valley power when the electricity is used in the low-valley, and the energy release is completed when the electricity is used in the peak, so that the energy storage efficiency is higher.
In summary, the energy storage system based on the working medium gas-liquid phase change and the operation method thereof provided by the embodiments of the invention can realize energy storage and release, and reduce the cost of user power; which may have in particular one or more of the following advantages:
(1) The high-pressure working medium such as high-pressure carbon dioxide is utilized to jet the low-pressure working medium such as low-pressure carbon dioxide, so that the mass flow of the low-pressure working medium can be regulated, the pressure of the mixed fluid at the outlet of the ejector 15 is regulated to the required energy storage pressure, the different energy storage pressure requirements of the system are met, meanwhile, the compressors 121 and 123 can be ensured to work under the design working condition, the applicability of the system is effectively increased, and the safety and stability of a unit are ensured;
(2) By introducing the organic Rankine cycle subsystem 18, low-temperature waste heat can be effectively utilized to generate power, and the energy storage efficiency and the energy utilization rate of the system are improved;
(3) The mass flow ratio of the high-pressure organic working medium and the low-pressure organic working medium is adjusted by controlling the opening degree of the fourth control valve 188, so that the waste heat of the carbon dioxide and the heat storage medium is fully utilized, the generated energy is increased, and the energy storage efficiency and the energy utilization rate of the system are further improved;
(4) Industrial cooling water is introduced into the working medium evaporator 14b, so that low-temperature waste heat of industrial production can be further utilized, and the efficiency and the energy utilization rate of the energy storage system are improved.
The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.
The above-described embodiments represent only a few embodiments of the present invention, which are described in more detail and are not to be construed as limiting the scope of the present invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the inventive concept, which fall within the scope of the present invention. Accordingly, the scope of the present application is to be determined by the following claims.
Claims (8)
1. The energy storage system based on the gas-liquid phase change of the working medium is characterized by comprising a gas storage, an energy storage assembly, an ejector and a liquid storage tank; the energy storage assembly comprises a compression energy storage part and a working medium condenser, the gas storage is connected with a working medium inlet of the compression energy storage part, a working medium outlet of the compression energy storage part is connected with a first inlet of the ejector, the gas storage is connected with a second inlet of the ejector through a first pipeline, an outlet of the ejector is connected with an inlet of the working medium condenser, and an outlet of the working medium condenser is connected with an inlet of the liquid storage tank; the ejector is used for mixing the low-pressure working medium from the gas storage and the high-pressure working medium compressed by the compression energy storage part to generate a working medium with adjustable pressure, the compressor in the compression energy storage part always operates under the design working condition, and the mass flow of the output high-pressure working medium is kept unchanged; the working medium is condensed into liquid by the working medium condenser and is conveyed to the liquid storage tank; the energy storage pressure of the energy storage system based on the gas-liquid phase change of the working medium is selected between a design energy storage pressure and a design energy storage pressure lower than the design energy storage pressure;
when the energy storage pressure is selected to be lower than the design energy storage pressure, the energy storage system based on the gas-liquid phase change of the working medium adjusts the energy storage pressure through the mass flow of the low-pressure working medium;
The working medium outlet of the compression energy storage part is connected with the inlet of the working medium condenser through a second pipeline; the first pipeline is provided with a first control valve, the second pipeline is provided with a second control valve, and a third control valve is arranged on a connecting pipeline between a working medium outlet of the compression energy storage part and a first inlet of the ejector; when the energy storage pressure is selected to be equal to the design energy storage pressure, the second control valve is opened, and the third control valve and the first control valve are closed; the high-pressure working medium output by the compression energy storage part is condensed into liquid state by the working medium condenser and is conveyed to the liquid storage tank; when the energy storage pressure is selected to be lower than the design energy storage pressure, the second control valve is closed, the third control valve is opened, the mass flow of the low-pressure working medium sucked by the ejector is adjusted through the first control valve by the energy storage system based on the gas-liquid phase change of the working medium so as to adjust the energy storage pressure, and the high-pressure working medium compressed by the compression energy storage part is the design energy storage pressure.
2. The energy storage system of claim 1, further comprising an energy release assembly comprising a working substance evaporator and an expansion energy release portion, wherein an inlet of the working substance evaporator is connected to an outlet of the liquid storage tank, an outlet of the working substance evaporator is connected to a working substance inlet of the expansion energy release portion, and a working substance outlet of the expansion energy release portion is connected to an inlet of the liquid storage tank; the energy storage system further comprises a heat exchange assembly, the heat exchange assembly comprises a cold storage tank and a heat storage tank, the cold storage tank and the heat storage tank are used for containing heat storage media, and the cold storage tank and the heat storage tank are arranged between the compression energy storage part and the expansion energy release part so as to form a heat exchange loop between the compression energy storage part and the expansion energy release part.
3. The energy storage system of claim 2, further comprising an organic rankine cycle subsystem, the organic rankine cycle subsystem comprising an inlet and an outlet, the inlet of the organic rankine cycle subsystem being connected to the working medium outlet of the expansion energy release portion and the outlet of the organic rankine cycle subsystem being connected to the inlet of the gas reservoir.
4. The energy storage system of claim 2, further comprising an organic rankine cycle subsystem, the organic rankine cycle subsystem comprising an inlet and an outlet, the inlet of the organic rankine cycle subsystem being connected to the expansion energy release portion and the outlet of the organic rankine cycle subsystem being connected to the inlet of the cold storage tank of the heat exchange assembly.
5. The energy storage system of claim 3 or 4, wherein the organic rankine cycle subsystem comprises an organic working medium expander, an organic working medium condenser, an organic working medium pump, and an organic working medium evaporator, wherein an outlet of the organic working medium condenser is connected with an inlet of the organic working medium pump, an outlet of the organic working medium pump is connected with a first inlet of the organic working medium evaporator, a first outlet of the organic working medium evaporator is connected with the inlet of the organic working medium expander, an outlet of the organic working medium expander is connected with the inlet of the organic working medium condenser, a second inlet of the organic working medium evaporator is the inlet of the organic rankine cycle subsystem, and a second outlet of the organic working medium evaporator is the outlet of the organic rankine cycle subsystem.
6. The energy storage system of claim 2, wherein the energy storage system further comprises an organic rankine cycle subsystem, the organic rankine cycle subsystem comprises a first organic working medium expander, a second organic working medium expander, an organic working medium condenser, a first organic working medium pump, a first organic working medium evaporator, a second organic working medium pump and a second organic working medium evaporator, an outlet of the organic working medium condenser is connected with an inlet of the first organic working medium pump, an outlet of the first organic working medium pump is connected with a first inlet of the first organic working medium evaporator and an inlet of the second organic working medium pump, an outlet of the second organic working medium pump is connected with a first inlet of the second organic working medium evaporator, a first outlet of the second organic working medium evaporator is connected with an inlet of the second organic working medium expander, a first outlet of the first organic working medium evaporator is connected with an outlet of the second organic working medium evaporator, an outlet of the second working medium evaporator is connected with an inlet of the second working medium evaporator, and an outlet of the second organic working medium evaporator is connected with an inlet of the second working medium evaporator.
7. The energy storage system of claim 4, wherein the expansion energy release section comprises at least one expansion energy release unit, each of the at least one expansion energy release unit comprising an energy release heat exchanger and a turbine, the cold side inlet of the energy release heat exchanger being the working medium inlet of the expansion energy release section or the outlet of the turbine connected to the last expansion energy release unit; the cold side outlet of the energy release heat exchanger is connected with the inlet of the turbine; the outlet of the turbine is connected with the cold side inlet of the energy release heat exchanger of the next expansion energy release unit or is used as a working medium outlet of the expansion energy release part; the hot side of the energy release heat exchanger is connected between the heat storage tank and the cold storage tank, and the hot side inlet of the energy release heat exchanger is connected with the outlet of the heat storage tank; an inlet of the organic Rankine cycle subsystem is connected with a hot side outlet of the energy release heat exchanger of at least one expansion energy release unit; and/or the number of the groups of groups,
The compression energy storage part comprises at least one compression energy storage unit, each compression energy storage unit in the at least one compression energy storage unit comprises an energy storage heat exchanger and a compressor, and an inlet of the compressor is used as a working medium inlet of the compression energy storage part or is connected with a hot side outlet of the energy storage heat exchanger of the last compression energy storage unit; the outlet of the compressor is connected with the hot side inlet of the energy storage heat exchanger, and the hot side outlet of the energy storage heat exchanger is connected with the inlet of the compressor of the next compression energy storage unit or is used as a working medium outlet of the compression energy storage part; and the cold side inlet and the cold side outlet of the energy storage heat exchanger are respectively connected with the outlet of the cold storage tank and the inlet of the heat storage tank.
8. The energy storage system of any of claims 1-4, 6-7, wherein the working fluid is carbon dioxide.
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| CN202311077489.8A CN116952046B (en) | 2023-08-24 | Energy storage system based on working medium gas-liquid phase change |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103244215A (en) * | 2013-05-08 | 2013-08-14 | 中国能源建设集团广东省电力设计研究院 | Method and device for improving energy conversion efficiency of compressed air energy storage technology |
| CN109826679A (en) * | 2019-01-17 | 2019-05-31 | 江苏大学 | A kind of tandem twin-stage evaporation organic rankine cycle system of mixing preheating |
| CN111075695A (en) * | 2019-12-25 | 2020-04-28 | 西安交通大学 | Compressed air energy storage system with ejector capable of enhancing air storage and air storage process of compressed air energy storage system |
| CN112985144A (en) * | 2021-02-07 | 2021-06-18 | 深圳市博德维环境技术股份有限公司 | Multistage compression energy storage device and method based on carbon dioxide gas-liquid phase change |
| CN114412749A (en) * | 2021-11-30 | 2022-04-29 | 西安交通大学 | Compressed air energy storage system and method for sliding pressure operation of ejector combined compressor unit |
| CN218669484U (en) * | 2022-10-09 | 2023-03-21 | 中国电力工程顾问集团中南电力设计院有限公司 | Non-afterburning type compressed air energy storage system coupled with organic Rankine cycle system |
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103244215A (en) * | 2013-05-08 | 2013-08-14 | 中国能源建设集团广东省电力设计研究院 | Method and device for improving energy conversion efficiency of compressed air energy storage technology |
| CN109826679A (en) * | 2019-01-17 | 2019-05-31 | 江苏大学 | A kind of tandem twin-stage evaporation organic rankine cycle system of mixing preheating |
| CN111075695A (en) * | 2019-12-25 | 2020-04-28 | 西安交通大学 | Compressed air energy storage system with ejector capable of enhancing air storage and air storage process of compressed air energy storage system |
| CN112985144A (en) * | 2021-02-07 | 2021-06-18 | 深圳市博德维环境技术股份有限公司 | Multistage compression energy storage device and method based on carbon dioxide gas-liquid phase change |
| CN114412749A (en) * | 2021-11-30 | 2022-04-29 | 西安交通大学 | Compressed air energy storage system and method for sliding pressure operation of ejector combined compressor unit |
| CN218669484U (en) * | 2022-10-09 | 2023-03-21 | 中国电力工程顾问集团中南电力设计院有限公司 | Non-afterburning type compressed air energy storage system coupled with organic Rankine cycle system |
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