Operation method of compressed air energy storage system with interstage waste heat circulation

Abstract

The invention relates to the technical field of new energy, in particular to an operation method of a compressed air energy storage system with interstage waste heat circulation.The method comprises the steps that to-be-compressed air is input into a first-stage compression side structure to be subjected to gas compression; the first steam generator is controlled to conduct heat exchange treatment on gas waste heat compressed by the first-stage compression side structure, and the operation is conducted circularly in sequence till the last evaporator conducts heat exchange on gas waste heat compressed by the last-stage compression side structure, the gas waste heat is fed into the gas cooler to be cooled and then stored in the gas storage chamber; and gas coming out of the gas storage chamber is reheated through the last-stage steam generator, the reheated gas enters the first-stage turbine side structure for turbine power generation, and the operation is cycled in sequence until the exhausted gas is reheated by the first evaporator and then is introduced into the last-stage turbine side structure of the expansion machine for turbine power generation. Therefore, the problems that in the related technology, the recovery rate of part of waste heat recovered through a heat exchanger is low, and the energy conversion efficiency is low are solved.

Description

Technical Field

[0001] The present application relates to the field of new energy technology, and in particular to an operation method of a compressed air energy storage system with an inter-stage waste heat cycle. Background Art

[0002] With the development of energy storage technology, advanced adiabatic compressed air energy storage has attracted extensive attention from relevant scholars and research institutions at home and abroad due to its long service life, cleanliness and environmental protection. Single-stage compressors have the disadvantages of high outlet gas temperature and high power consumption. Therefore, multi-stage compressors are generally used, and the compressed gas between stages is cooled. The heat released by the inter-stage cooling of the compressor has a low temperature and belongs to low-grade thermal energy, and the emission volume is also relatively large. If all of it is taken away by cooling water, it will cause energy waste. Therefore, it is considered to recycle the waste heat of the inter-stage cooling of the compressor to achieve energy saving and emission reduction.

[0003] In the related art, for the recovery of waste heat from inter-stage cooling of compressors, hot water required by the factory or employees is mostly prepared through a heat exchanger. This method recovers the waste heat of the compressor and avoids energy waste, but the recovery rate is low and the quality of the converted energy is also low, and the energy conversion efficiency is low. Summary of the invention

[0004] The present application provides an operating method of a compressed air energy storage system with an inter-stage waste heat cycle to solve the problems of low recovery rate and low energy conversion efficiency of recovering part of the waste heat using a heat exchanger in the related art.

[0005] The first aspect of the present application provides an operating method of a compressed air energy storage system with an inter-stage waste heat cycle, wherein the compressed air energy storage system comprises: an air storage chamber, a generator, a multi-stage compression side structure and a multi-stage turbine side structure; each stage of the compression side structure and each stage of the turbine side structure share a steam generator, wherein the steam generator exchanges waste heat of the gas of the compression side structure and the turbine side structure and provides heat to the outside, and the last stage of the turbine side structure is connected to the generator; a gas cooler of each stage of the compression side structure is arranged behind the steam generator, wherein the gas cooler is used to cool the gas after heat exchange, and the gas cooler is connected to the next stage of the compression side structure, and the gas cooler of the last stage of the compression side structure is connected to the air storage chamber, wherein the method comprises the following steps: After the gas is input into the first-stage compression side structure for compression, the first steam generator is controlled to perform heat exchange treatment on the residual heat of the gas compressed by the first-stage compression side structure; the gas after heat exchange is passed into the second-stage compressor structure for compression and work again and then input into the second steam generator, and the operation is cyclically performed in sequence until the last evaporator performs heat exchange on the residual heat of the gas compressed by the last-stage compression side structure and sends it to the gas cooler for cooling and then stores it in the gas storage chamber; the gas coming out of the gas storage chamber is reheated by the last-stage steam generator, and the reheated gas enters the first-stage turbine side structure for turbine power generation, and then the gas discharged from the first-stage turbine side structure enters the penultimate steam generator again for reheating, and the operation is cyclically performed in sequence until the first evaporator reheats the discharged gas and then passes it into the last-stage turbine side structure of the expander for turbine power generation.

[0006] Optionally, one end of the first steam generator is connected to the first-stage compression side structure, the last-stage turbine side structure and the additional turbine, and the other end is connected to the gas cooler, the last-stage turbine side structure and the booster pump; one end of the second evaporator is connected to the second-stage compressor structure, the last-stage turbine side structure and the additional turbine, and the other end is connected to the gas cooler, the third-to-last turbine side structure and the booster pump, which are connected in sequence; one end of the last evaporator is connected to the last-stage compression side structure, the first-stage turbine side structure and the additional turbine, and the other end is connected to the gas cooler, the booster pump and the air storage chamber.

[0007] Optionally, one end of the additional turbine is connected to each steam generator, and the other end is connected to the condenser.

[0008] Optionally, the compressed air energy storage system further includes: an additional turbine, wherein one end of the additional turbine is connected to each steam generator, and the other end is connected to the condenser.

[0009] Optionally, the reheated gas from each steam generator is used to generate residual heat energy for turbine power generation.

[0010] Optionally, the compressed air energy storage system further includes: a condenser, wherein one end of the condenser is connected to the last-stage turbine side structure and the additional turbine, and the other end is connected to the boost pump.

[0011] Optionally, a condenser is used to cool the exhaust gas from the last stage turbine side structure and the additional turbine.

[0012] Optionally, it further includes: a booster pump, wherein one end of the booster pump is connected to the condenser, and the other end of the booster pump is connected to each steam generator.

[0013] Optionally, the condenser exhaust gas is re-pressurized and sent back to the steam generator.

[0014] Optionally, the compressed air energy storage system further includes: the compressed air energy storage system further includes: a heat storage tank and a target reheat device, wherein one end of the heat storage tank is connected to each steam generator, and the other end is connected to the target reheat device.

[0015] Optionally, it also includes: a target reheat device, wherein the target reheat device includes: a photothermal collector device and an electric heating device, the photothermal collector device is used to collect solar energy to supplement heat to the heat storage tank, and the electric heating device is used to heat the heat storage tank.

[0016] Therefore, this application has at least the following beneficial effects:

[0017] In the embodiment of the present application, each stage of the compression side structure and each stage of the turbine side structure share a steam generator, and heat is exchanged for the gas waste heat of the compression side structure and the turbine side structure, and heat is provided to the outside. The gas cooler of each stage of the compression side structure is arranged behind the steam generator, and is used to cool the gas after heat exchange coming out of the steam generator. The gas can be cooled to a suitable cooling temperature suitable for passing into the inlet of the next stage compressor, and the temperature of the gas to be passed into the next stage compressor can be stabilized, thereby replacing multiple traditional heat exchangers, avoiding energy waste, and improving energy recovery efficiency and energy conversion efficiency, so that the inter-stage waste heat can be fully utilized for re-compression and expansion with the turbine side structure to generate electricity. In addition, the hot working fluid in the heat storage tank can supplement the heat required for the steam generator to reheat the turbine side gas, thereby increasing the gas temperature at the inlet of the two-stage turbine passing into the turbine side, improving the system's electric-electric conversion efficiency, and thereby improving the power generation efficiency of the entire system.

[0018] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0020] Figure 1 A block diagram of a compressed air energy storage system with an inter-stage waste heat recovery cycle provided according to an embodiment of the present application;

[0021] Figure 2 A schematic diagram of an operation method of a compressed air energy storage system with an inter-stage waste heat recovery cycle provided according to an embodiment of the present application;

[0022] Figure 3 The present invention provides a specific flow chart of a steam generator according to an embodiment of the present application.

[0023] Description of reference numerals: gas storage chamber 100 , generator 200 , compression side structure 300 , turbine side structure 400 , steam generator 500 and gas cooler 600 . DETAILED DESCRIPTION

[0024] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0025] The following describes the operating method of the compressed air energy storage system with an interstage waste heat recovery cycle of the embodiment of the present application with reference to the accompanying drawings. In view of the problem that the recovery rate of part of the waste heat recovered by the heat exchanger in the related technology mentioned in the background technology center is low and the energy conversion efficiency is low, the present application provides an operating method of a compressed air energy storage system with an interstage waste heat recovery cycle, in which each stage of the compression side structure and each stage of the turbine side structure share a steam generator, and the gas waste heat of the compression side structure and the turbine side structure are heat exchanged and provided to the outside, and the gas cooler of each stage of the compression side structure is arranged behind the steam generator, which is used to cool the gas after heat exchange, replacing the traditional multiple heat exchangers, avoiding energy waste, and improving energy recovery efficiency and energy conversion efficiency, so that the interstage waste heat can be fully utilized for re-compression and expansion power generation with the turbine side structure, thereby improving the power generation efficiency of the entire system. As a result, the problems of low recovery rate and low energy conversion efficiency of part of the waste heat recovered by the heat exchanger in the related technology are solved.

[0026] Specifically, Figure 1 A block diagram of a compressed air energy storage system with an inter-stage waste heat recovery cycle provided in an embodiment of the present application.

[0027] like Figure 1As shown, the compressed air energy storage system 10 with an inter-stage waste heat recovery cycle includes: an air storage chamber 100, a generator 200, a compression side structure 300, a turbine side structure 400, a steam generator 500 and a gas cooler 600.

[0028] Among them, each stage of compression side structure 300 and each stage of turbine side structure 400 share a steam generator 500, wherein the steam generator 500 exchanges waste heat of the gas of the compression side structure 300 and the turbine side structure 400 and provides heat to the outside, and the last stage of turbine side structure 400 is connected to the generator; the gas cooler of each stage of compression side structure 300 is arranged after the steam generator 500, wherein the gas cooler 600 is used to cool the gas after heat exchange, and the gas cooler 600 is connected to the next stage of compression side structure 300, and the gas cooler 600 of the last stage of compression side structure 300 is connected to the gas storage chamber 100.

[0029] Among them, each stage of the compression mechanism 300 is a compressor, and each stage of the turbine side structure 400 is a turbine.

[0030] It can be understood that in the embodiment of the present application, each stage of the compression side structure and each stage of the turbine side structure share a steam generator, and heat is exchanged for the gas waste heat of the compression side structure and the turbine side structure, and heat is provided to the outside. The gas cooler of each stage of the compression side structure is arranged behind the steam generator, and is used to cool the gas after heat exchange, and cool the gas to a suitable stable temperature suitable for passing into the inlet of the next stage compressor, replacing the traditional multiple heat exchangers, avoiding energy waste, and improving energy recovery efficiency and energy conversion efficiency, so that the inter-stage waste heat can be fully utilized for re-compression and expansion with the turbine side structure to generate electricity. The hot working medium in the heat storage tank can supplement the heat required for the steam generator to reheat the turbine side gas, which can increase the turbine inlet gas temperature on the turbine side, thereby improving the power generation efficiency of the entire system.

[0031] Specifically, the steam generator is a key part of the compressed air energy storage system with an interstage waste heat recovery cycle; the models of the compressor and turbine are as follows:

[0032]

[0033] W c =C p,a m a (T out -T in )(1.1b)

[0034]

[0035] W t =C p,a m a (Tin -T out )(1.1d)

[0036] Wherein, formula (1.1a) is the temperature change model in the compressor unit, T out is the outlet air temperature; T in is the intake air temperature; c is the compression ratio; n is the adiabatic index; (1.1b) is the output power model of the compressor, W c is the power consumption of the compressor unit; C p,a is the specific heat capacity of air; m a is the air mass; (1.1c) is the outlet temperature model of the turbine, T out is the outlet air temperature; T in is the intake air temperature; t is the expansion ratio; (1.1d) is the output power model of the turbine, W t is the output work of the expansion unit; C p,a is the specific heat capacity of air; m a is the air quality; T out is the outlet air temperature; T in is the intake air temperature.

[0037] The heat exchanged between the air in the air storage chamber and the inner wall of the air storage chamber is:

[0038] Q=U cv +h out m out -h in m in +W(1.2a)

[0039] Among them, U cv is the change in thermodynamic energy of air; W is the work exchanged between air and the environment; h is the convection heat transfer coefficient; and m is the air mass.

[0040] The relationship between the total energy change in the gas storage chamber is:

[0041] Q S =m in H in -m out H out -hA(TT w )(1.2b)

[0042] Among them, Q S is the total energy; H is the air enthalpy; A is the heat exchange area; T is the air temperature; T W is the wall temperature of the air storage chamber.

[0043] The heat exchanged between the air in the air storage chamber and the inner wall of the air storage chamber is:

[0044]

[0045] Where ρ is air density; t is time; V is the volume of the air storage chamber; T is air temperature; T W is the wall temperature of the air storage chamber.

[0046] In an embodiment of the present application, one end of the first steam generator is connected to the first-stage compression side structure, the last-stage turbine side structure and the additional turbine, and the other end is connected to the gas cooler, the last-stage upper-stage turbine side structure and the booster pump. One end of the second evaporator is connected to the second-stage compressor structure, the last-stage upper-stage turbine side structure and the additional turbine, and the other end is connected to the gas cooler, the third-to-last turbine side structure and the booster pump, which are connected in sequence. One end of the last evaporator is connected to the last-stage compression side structure, the first-stage turbine side structure and the additional turbine, and the other end is connected to the gas cooler, the booster pump and the air storage chamber.

[0047] It should be noted that the high-temperature gas discharged from the compression side structure enters the steam generator for heat exchange, which can recover the heat generated during the compression process. The gas coming out of the gas storage chamber will pass through the steam generator for reheating before entering the turbine side structure. The previously stored compression side heat can be used to increase the inlet temperature of the gas entering the turbine, thereby increasing the working efficiency of the turbine and further improving the electric-electric conversion efficiency of the entire system. The steam generator can use the recovered heat to heat and generate steam, which can be further used to drive additional turbines or other thermal equipment to achieve efficient energy conversion. The steam generator can also transfer excess heat to the phase change material or hot water in the heat storage tank for subsequent use, which helps to improve the thermal efficiency of the entire system, reduce energy loss, and dynamically adjust heat distribution according to system needs.

[0048] Specifically, the energy conservation equation of the tube wall of the steam generator is:

[0049]

[0050] where c W is the specific heat capacity of the tube segment; ρ W is the metal tube wall density; A W is the heat transfer area of ​​the pipe wall; L is the pipe length; a0 is the convection heat transfer coefficient between the heat source and the pipe wall; T0 is the temperature of the heat source outside the pipe; T W is the tube wall temperature; a i , T i , A iThey are respectively the convection heat transfer coefficient between the other heat source fluid and the pipe wall, the temperature of the other heat source outside the pipe, and the heat transfer area between the other heat source and the pipe wall (calculated based on the incoming heat source);

[0051] The working fluid in the steam generator flows in the tube for heat exchange, and the single-phase countercurrent heat transfer coefficient of the liquid phase and the gas phase is:

[0052]

[0053] Where: h is the heat transfer coefficient; Re is the Reynolds number; Pr is the Prandtl number; d e is the hydraulic diameter; k is the coefficient constant for different working fluids.

[0054] In an embodiment of the present application, one end of the first gas cooler is connected to the first steam generator, and the other end is connected to the second-stage compression side structure; one end of the second gas cooler is connected to the second steam generator, and the other end is connected to the third-stage compression side structure, and the two are connected in sequence; one end of the last gas cooler is connected to the last steam generator, and the other end is connected to the gas storage chamber.

[0055] It should be noted that in the multi-stage compression process, the temperature of the air will increase significantly after each stage of compression. The gas cooler cools the high-temperature gas discharged from the steam generating area on the compression side to a suitable temperature by exchanging heat with the cooling medium, thereby reducing energy consumption in the subsequent compression process and preventing equipment from being damaged due to overheating. By lowering the gas temperature, the volume of the gas can be reduced, thereby improving the suction efficiency of the next stage compressor. Heat exchange media (such as thermal oil, etc.) can also be used to use excess heat in the steam generator for other purposes, such as user heating, thereby improving the overall energy utilization of the system.

[0056] In the embodiment of the present application, it also includes: an additional turbine.

[0057] One end of the additional turbine is connected to each steam generator, and the other end is connected to the condenser, so as to utilize the residual heat energy generated by the reheated gas of each steam generator to generate turbine power.

[0058] It can be understood that the additional turbine of the embodiment of the present application extracts the remaining energy by further expanding the reheated gas of each steam generator and converts it into electrical energy, thereby making full use of low-grade thermal energy that might otherwise be wasted and improving the overall power generation efficiency of the system.

[0059] In the embodiment of the present application, it also includes: a condenser.

[0060] One end of the condenser is connected to the last stage turbine side structure and the additional turbine, and the other end is connected to the booster pump for cooling the gas discharged from the last stage turbine side structure and the additional turbine.

[0061] It can be understood that the condenser of the embodiment of the present application can be responsible for cooling the gas exhausted from the turbine. Since the turbine releases a large amount of heat in the process of power generation, the temperature of the exhaust gas is relatively high. Therefore, the condenser reduces the temperature of this part of high-temperature gas by heat exchange with the cooling medium (such as cold water) for subsequent processing or recycling. At the same time, the heat in this part of the gas is recovered and used for the reheating process inside the system, thereby improving the overall thermal efficiency of the system.

[0062] Specifically, the heat transfer coefficient of the condenser is:

[0063]

[0064] Where: λ is the thermal conductivity; μ is the dynamic viscosity; T s is the temperature of the working fluid in the condenser; g and γ are coefficient constants; ρ L is the density of the cold working fluid; (ρ L -ρ V ) is the density difference between the cold and hot working fluids.

[0065] In the embodiment of the present application, it also includes: a booster pump.

[0066] One end of the booster pump is connected to the condenser, and the other end is connected to each steam generator, so as to re-pressurize the gas discharged from the condenser and send it back to the steam generator.

[0067] It can be understood that the booster pump of the embodiment of the present application ensures that the gas can smoothly re-enter the steam generator from the condenser, so that the gas pressure is restored to a sufficiently high level so that it can enter the system circulation again, so as to facilitate the subsequent effective reuse of the gas, thereby improving the overall energy utilization.

[0068] Specifically, the output work expression of the booster pump is:

[0069] W pump =m wf (h out -h in )(1.3a)

[0070] In formula (1.3a), m wf is the mass flow rate of the working fluid; h is the specific enthalpy of the working fluid;

[0071] The pump flow rate is:

[0072]

[0073] Where n is the pump speed; n0 is the initial speed; q0 is the initial flow rate.

[0074] In the embodiment of the present application, it also includes: a heat storage tank.

[0075] One end of the heat storage tank is connected to each steam generator, and the other end is connected to the target reheat device to store excess heat.

[0076] It can be understood that the heat storage tank in the embodiment of the present application is used to store excess heat generated in the system. This heat can be generated during the compression process or recovered from the gas discharged from the turbine. The heat supply can be dynamically adjusted according to the needs of the system. When the heat in the system is insufficient, the heat storage tank can release the previously stored heat to supplement the heat demand of the system, so as to maintain a stable operating state under different working conditions and avoid affecting the efficiency of the system due to insufficient heat.

[0077] In an embodiment of the present application, it also includes: a target reheat device, wherein the target reheat device includes: a photothermal collector and an electric heating device, wherein the target reheat device is connected to a heat storage tank, and is used to collect solar energy to supplement heat to the heat storage tank, and reheat the hot working medium in the heat storage tank.

[0078] It can be understood that the target reheat device of the embodiment of the present application can collect solar energy to supplement the missing heat when the heat in the steam generator is insufficient, provide additional thermal energy for the system, and thus improve the energy conversion efficiency of the entire system. In addition, the hot working fluid in the heat storage tank can supplement the heat required by the steam generator to reheat the turbine side gas, thereby increasing the gas temperature at the inlet of the two-stage turbine on the turbine side, improving the system's electric-electric conversion efficiency, and further improving the power generation efficiency of the entire system.

[0079] It should be noted that the target reheating device can be any device suitable for reheating the hot working medium in the heat storage tank, including but not limited to an electric heating device.

[0080] Specifically, the heat generation power model of the thermal collector is:

[0081] Q sf =A sf DNI t I L I T η OPT,R η END η CLN σ(1.4)

[0082] Where: A sf DNI is the mirror area of ​​the solar thermal collector system; t is the direct solar radiation intensity at time t; I L and I T are the longitudinal and transverse components of the incident angle correction coefficient respectively; η OPT,R is the optical efficiency of the mirror field; η ENDis the terminal loss optical efficiency; η CLN is the cleanliness coefficient; σ is the heat transfer coefficient of the solar cooler.

[0083] According to the compressed air energy storage system with an inter-stage waste heat recovery cycle proposed in the embodiment of the present application, each stage of the compression side structure and each stage of the turbine side structure share a steam generator, and the gas waste heat of the compression side structure and the turbine side structure are both exchanged, and heat is provided to the outside. The gas cooler of each stage of the compression side structure is arranged behind the steam generator, and is used to cool the gas after heat exchange. The gas can be cooled to a suitable stable temperature suitable for passing into the inlet of the next stage compressor, replacing the traditional multiple heat exchangers, avoiding energy waste, and improving energy recovery efficiency and energy conversion efficiency, so that the inter-stage waste heat can be fully utilized for re-compression and expansion with the turbine side structure to generate electricity. The hot working medium in the heat storage tank can supplement the heat required for the steam generator to reheat the turbine side gas, which can increase the turbine inlet gas temperature on the turbine side, thereby improving the power generation efficiency of the entire system.

[0084] The following will be combined Figure 2 and Figure 3 The operation method of the compressed air energy storage system with interstage waste heat recovery cycle of the present application is described by using a specific embodiment, wherein the compressed air energy storage system with interstage waste heat recovery cycle of the present application adopts a first compressor C1, a second compressor C2, a first turbine T1, a second turbine T2, a first steam generator, a second steam generator, a first gas cooler, a second gas cooler, an air storage chamber, a condenser, a booster pump, a heat storage tank, a target reheat device and an additional turbine, as follows:

[0085] (1) Start the compression process and turbine process

[0086] Compression process: After the air (natural gas) is compressed by compressor C1, it enters the first channel of the steam generator for slight heat exchange (the temperature is slightly reduced). The gas coming out of the steam generator is then cooled by the gas cooler, and then enters compressor C2 for compression and work. After being compressed by C2, it is discharged and then enters the second steam generator for slight heat exchange, and then enters the gas cooler for cooling again. After that, it enters the gas storage chamber through the throttle valve to complete the energy storage process.

[0087] Turbine process: The gas coming out of the gas storage chamber passes through the second channel of the steam generator for reheating. The reheated gas enters the expander T1 for turbine power generation. Then the gas discharged from T1 enters the second channel of the first steam generator again for reheating, and finally enters the expander T2 for turbine power generation.

[0088] (2) Start the waste heat circulation process

[0089] After the gas discharged from turbine T2 is cooled by the condenser, it is pressurized by the booster pump and enters the steam generator again. Part of it is used to pass into T0 for turbine power generation again, and part of the gas and the gas discharged from the compressor enter the gas cooler again for the previous compression process. If there is not enough heat in the steam generator, the heat is supplemented by the solar collector, and the excess heat of the collector is used for heating the user. If there is excess heat in the steam generator, the excess heat can also be collected by the heat storage device for heating.

[0090] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0091] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0092] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one or a combination of multiple of the following technologies known in the art: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0093] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

Claims

1. A method for operating a compressed air energy storage system with an interstage waste heat cycle, characterized in that: The compressed air energy storage system comprises: an air storage chamber, a generator, a multi-stage compression side structure and a multi-stage turbine side structure, each stage of the compression side structure and each stage of the turbine side structure share a steam generator, wherein the steam generator exchanges heat with the gas waste heat of the compression side structure and the turbine side structure and provides heat to the outside, and the last stage of the turbine side structure is connected to the generator; the gas cooler of each stage of the compression side structure is arranged behind the steam generator, wherein the gas cooler is used to cool the gas after heat exchange, the gas cooler is connected to the next stage of the compression side structure, and the gas cooler of the last stage of the compression side structure is connected to the air storage chamber; wherein the method comprises the following steps: After the air to be compressed is input into the first-stage compression side structure for gas compression, the first steam generator is controlled to perform heat exchange treatment on the residual heat of the gas compressed by the first-stage compression side structure; the gas after heat exchange is passed into the second-stage compressor structure for re-compression and work, and then input into the second steam generator, and the operation is cyclically performed in sequence until the last evaporator performs heat exchange on the residual heat of the gas compressed by the last-stage compression side structure, and sends it to the gas cooler for cooling and then stores it in the gas storage chamber; The gas coming out of the gas storage chamber is reheated through the last stage steam generator, and the reheated gas enters the first stage turbine side structure for turbine power generation. Thereafter, the gas exhausted from the first stage turbine side structure enters the penultimate stage steam generator for reheating again, and the cycle is repeated in sequence until the first evaporator reheats the exhausted gas and then enters the last stage turbine side structure of the expander for turbine power generation.

2. The operating method of the compressed air energy storage system with interstage waste heat cycle according to claim 1, characterized in that: One end of the first steam generator is connected to the first-stage compression side structure, the last-stage turbine side structure and the additional turbine, and the other end is connected to the gas cooler, the turbine side structure of the last stage and the booster pump. One end of the second evaporator is connected to the second-stage compressor structure, the turbine side structure of the last stage and the additional turbine, and the other end is connected to the gas cooler, the third-to-last turbine side structure and the booster pump, which are connected in sequence. One end of the last evaporator is connected to the last-stage compression side structure, the first-stage turbine side structure and the additional turbine, and the other end is connected to the gas cooler, the booster pump and the air storage chamber. One end of the first gas cooler is connected to the first steam generator, and the other end is connected to the second-stage compression side structure. One end of the second gas cooler is connected to the second steam generator, and the other end is connected to the third-stage compression side structure, which are connected in sequence. One end of the last gas cooler is connected to the last steam generator, and the other end is connected to the air storage chamber.

3. The operating method of the compressed air energy storage system with interstage waste heat cycle according to claim 2, characterized in that: One end of the additional turbine is connected to each steam generator, and the other end is connected to the condenser.

4. The method for operating a compressed air energy storage system with an interstage waste heat cycle according to claim 3, characterized in that: The residual heat energy generated by the reheated gas of each steam generator is input into the additional turbine for turbine power generation.

5. The operating method of the compressed air energy storage system with interstage waste heat cycle according to claim 1, characterized in that: The compressed air energy storage system further includes: a condenser, wherein one end of the condenser is connected to the last stage turbine side structure and the additional turbine, and the other end is connected to the booster pump.

6. The operating method of the compressed air energy storage system with interstage waste heat cycle according to claim 5, characterized in that: The condenser is used to cool the gas discharged from the last stage turbine side structure and the additional turbine, so as to compress and store the excess gas and generate electricity for turbine respectively.

7. The operating method of the compressed air energy storage system with interstage waste heat cycle according to claim 6, characterized in that: The compressed air energy storage system further includes: a booster pump, wherein one end of the booster pump is connected to the condenser, and the other end of the booster pump is connected to each steam generator.

8. The method for operating a compressed air energy storage system with an interstage waste heat cycle according to claim 7, characterized in that: The condenser exhaust gas is repressurized and sent back to the steam generator.

9. The method for operating a compressed air energy storage system with an interstage waste heat cycle according to claim 1, characterized in that: The compressed air energy storage system further includes: a heat storage tank and a target reheat device, wherein one end of the heat storage tank is connected to each steam generator, and the other end is connected to the target reheat device.

10. The operating method of the compressed air energy storage system with interstage waste heat cycle according to claim 9, characterized in that: The target reheating device includes: a photothermal heat collecting device and an electric heating device. The photothermal heat collecting device is used to collect solar energy to supplement heat to the heat storage tank, and the electric heating device is used to heat the heat storage tank.

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