Method and system for improving advanced adiabatic compressed air energy storage compression heat recovery rate

Abstract

The system comprises an air compression unit and an air turbine, an energy storage and release unit comprises heat exchanger tube pass inlets which are connected with the air compression unit through pipelines, and tube pass outlets of the heat exchangers are connected with an air storage device through pipelines; a shell pass inlet is connected with a low-temperature water storage tank through a pipeline and a low-temperature circulating water pump, and a tube pass outlet is connected with a high-temperature water storage tank through a pipeline; a primary flow-in port of the gas ejector is connected with the gas storage device through a pipeline, and a secondary flow-in port of the gas ejector is communicated with air; a gas inlet of the reheater is connected with a mixed flow outlet of the jet air extractor through a pipeline, a gas outlet of the reheater is connected with the air turbine through a pipeline, a liquid inlet of the reheater is connected with the high-temperature water storage tank through a pipeline and a high-temperature circulating water pump, and a liquid outlet of the reheater is connected with the low-temperature water storage tank through a pipeline. The invention further provides an advanced adiabatic compressed air energy storage compression heat recovery method, and the recovery rate of compression heat can be effectively increased.

Description

Technical Field

[0001] The present invention relates to the field of energy technology, and in particular to a method and system for improving the compression heat recovery rate of advanced adiabatic compressed air energy storage. Background Art

[0002] The large-capacity advanced adiabatic compressed air energy storage system has many advantages such as large energy storage capacity, long energy release time, high system efficiency, zero fuel consumption, zero pollution emissions, fast startup speed, and strong regulation ability. It can play a key role in alleviating the expansion of transmission lines, shaving peak power loads, and large-scale consumption of new energy electricity. It is an important supporting technology to ensure the safe and stable operation of the power grid and its realization as scheduled.

[0003] At present, the system efficiency (electric-to-electricity conversion efficiency) of the most advanced adiabatic compressed air energy storage power station can reach 70%, that is, for every 100 kWh of electricity consumed by the compressor, the stored compressed air can generate 70 kWh of electricity in the air turbine, with a loss of 30 kWh of electricity. The losses of advanced adiabatic compressed air energy storage systems are mainly concentrated in the compression, heat storage and expansion work links. Figure 1 It shows the energy conversion process and loss of each link. Among them, 1-2 represents the adiabatic compression process of air inside the compressor; 2-3 is the process of air being cooled by circulating water in the interstage heat exchanger, and the corresponding circulating water is heated in 5-6; 3-4 is the process of air being cooled in the open water cooler, and the corresponding open water is heated in 7-8; 6-5 represents the cooling process of circulating water in the reheat heat exchanger, and at the same time, the process of air being heated is 9-10; the work process of air inside the air turbine is 10-11.

[0004] There are irreversible losses in each link, which leads to a decrease in the system's ability to do work. These irreversible losses come from factors such as air friction during compression and expansion, end difference during heat exchange, etc. Figure 1 As shown in Q1 in . Domestic and foreign scholars have done a lot of research to reduce these losses. Due to the end difference in the heat exchange process, after two heat exchanges, the maximum air temperature in the turbine is about 20°C lower than the maximum air temperature in the compressor. For example, for the medium-temperature technology route, the maximum air temperature in the air turbine is 170°C, while the maximum air temperature in the compressor is 195°C. Since the total amount of air during the compression and expansion process remains unchanged, the compression heat is greater than the heat absorbed by the air reheating. The excess compression heat is taken away by open cooling water, such as Figure 1 The heat is finally discharged to the atmosphere, and the heat loss is Q2. For the medium temperature scheme with four-stage compression and three-stage expansion, Q2 is 16% of the total compression heat.

[0005] Reducing the heat exchange end difference can increase the utilization ratio of compression heat, increase the turbine inlet air temperature, and increase the turbine work capacity. The heat exchange end difference calculation formula is shown in (1).

[0006]

[0007] In the formula, δt is the end difference of the heat exchanger, ℃; Δt is the air temperature rise, ℃; k is the heat transfer coefficient, kW / m2; A is the heat exchange area, m2; C p is the specific heat capacity of air at constant pressure, kJ / (kg·℃); D is the air flow rate, kg / s.

[0008] From formula (1), it can be seen that when the heat exchange end difference is reduced from 10℃ to 5℃, Q2 can be fully utilized. At this time, the heat exchange area needs to be increased by 25%, and the equipment investment will increase significantly. If the heat exchange end difference remains unchanged, the air flow rate to absorb Q2 needs to increase by 16%, while the heat exchange area only increases by 10%, thereby greatly reducing the equipment investment.

[0009] If the above objectives can be achieved, it is necessary to design a system and method that can effectively improve the compression heat recovery rate without significantly increasing the heat exchange area while keeping the heat exchanger end difference unchanged. This is an urgent problem to be solved. Summary of the invention

[0010] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method and system for improving the compression heat recovery rate of advanced adiabatic compressed air energy storage, aiming to solve the problems raised in the technical background, and can effectively improve the compression heat recovery rate under the premise of unchanged heat exchanger end difference and without significantly increasing the heat exchange area.

[0011] In order to solve the above technical problems, the first implementation scheme provided by the present invention is a system for improving the compression heat recovery rate of advanced adiabatic compressed air energy storage, including an air compression unit and an air turbine, wherein the air compression unit compresses low-temperature and low-pressure air and outputs high-temperature air for energy storage when valley electricity or wind and solar power generation resources are sufficient, and further includes:

[0012] The energy storage and release unit includes a heat exchanger, a gas storage device, an ejector, a reheater, a low-temperature water storage tank and a high-temperature water storage tank, wherein:

[0013] Each heat exchanger is used to exchange heat and store energy between the high-temperature air output by the air compression unit and the low-temperature liquid working medium. Its tube-side inlet is connected to the air compression unit through a pipeline, its tube-side outlet is connected to the air storage device through a pipeline, its shell-side inlet is connected to the low-temperature water storage tank through a pipeline and a low-temperature circulating water pump, and its tube-side outlet is connected to the high-temperature water storage tank through a pipeline;

[0014] The emanator is used to increase the air flow rate and improve the compression heat recovery ratio. The emanator has a primary flow inlet, a secondary flow inlet and a mixed flow outlet. The primary flow inlet is connected to the air storage device through a pipeline, and the secondary flow inlet is connected to the air, and is used to mix the low-temperature air sent in by the primary flow inlet with the air sent in by the secondary flow and flow out from the mixed flow outlet;

[0015] Each reheater is used to release energy by exchanging heat between the gas flowing out of each mixed flow outlet and the high-temperature liquid working medium. Its gas inlet is connected to the mixed flow outlet through a pipeline, its gas outlet is connected to the air turbine through a pipeline, its liquid inlet is connected to the high-temperature water storage tank through a pipeline and a high-temperature circulating water pump, and its liquid outlet is connected to the low-temperature water storage tank through a pipeline.

[0016] Preferably, there are multiple emanator vacuum pumps and multiple reheaters, and the multiple emanator vacuum pumps and the multiple reheaters correspond one to one and are connected in series through pipelines.

[0017] Preferably, there are multiple emanator vacuum pumps and multiple reheaters, and the mixed flow outlets of the multiple emanator vacuum pumps are connected to the same output pipeline, so that the multiple emanator vacuum pumps are connected in parallel, and the gas inlet of each reheater is connected to the output pipeline through a pipeline.

[0018] Preferably, the emanator is further provided with a controller, the secondary flow inlet is provided with a regulating valve, the mixed flow outlet of the emanator is provided with a pressure measuring element, and the controller is connected to the regulating valve and the pressure measuring element, and is used to adjust the opening of the regulating valve by the mixed flow outlet pressure obtained by the pressure measuring element;

[0019] When the measured value of the pressure measuring element at the mixed flow outlet of the ejector is lower than the target set value, the controller closes the regulating valve to reduce the air intake of the ejector, thereby increasing the mixed flow outlet pressure of the ejector; when the measured value of the pressure measuring element at the mixed flow outlet of the ejector is higher than the target set value, the controller opens the regulating valve to increase the air intake of the ejector, thereby reducing the mixed flow outlet pressure of the ejector.

[0020] Preferably, all the pipelines are provided with valves.

[0021] Preferably, all air compression units include multiple air compressors and multiple synchronous motors, the multiple air compressors and the multiple synchronous motors correspond one to one and are coaxially connected through a coupling.

[0022] Preferably, the air turbine is coaxially connected to the generator for releasing energy during peak power consumption periods to ensure power supply during peak power consumption periods.

[0023] Preferably, pipelines connected to gas outlets of a plurality of reheaters are connected in parallel and then fed into an air turbine.

[0024] The second technical solution provided by the present invention is: a method for improving the compression heat recovery rate of advanced adiabatic compressed air energy storage, comprising the following steps:

[0025] When storing energy: the air compressor is driven by a synchronous motor to compress the low-temperature and low-pressure air from the atmosphere, and the output high-temperature and high-pressure air is sent to the tube side of the heat exchanger through a pipeline. The high-pressure cold water in the low-temperature water storage tank is sent to the shell side of the heat exchanger through a pipeline and a low-temperature circulating water pump. In the heat exchanger, the high-temperature and high-pressure air and the high-pressure cold water exchange heat and store energy. After the heat exchange, the high-temperature air becomes low-temperature and high-pressure air and is stored in the air storage device. After the heat exchange, the high-pressure cold water a becomes high-pressure hot water a and is sent to the high-temperature water storage tank.

[0026] When releasing energy: the low-temperature and high-pressure air in the gas storage device is sent into the ejector through the primary inlet, and the external air is sucked in through the secondary inlet, and the air is mixed in the ejector and sent to the gas inlet of the reheater through the mixed outlet of the ejector. The high-pressure hot water b in the high-temperature water storage tank is sent into the reheater through the high-temperature circulating water pump and pipeline, and the high-pressure hot water b exchanges heat with the mixed gas sent into the reheater to release energy;

[0027] When the measured value of the mixed flow outlet of the emanator is lower than the target set value, the controller closes the regulating valve to reduce the air intake of the emanator, thereby increasing the mixed flow outlet pressure of the emanator; when the measured value of the mixed flow outlet of the emanator is higher than the target set value, the controller opens the regulating valve to increase the air intake of the emanator, thereby decreasing the mixed flow outlet pressure of the emanator;

[0028] The high-pressure and low-temperature mixed gas is converted into high-temperature and high-pressure gas and then sent into the air turbine to drive the generator to rotate, which is used to output electrical energy during peak electricity consumption hours.

[0029] Preferably, the multiple synchronous motors compress air to store energy during off-peak hours or when wind and solar power generation resources are sufficient, and the air turbine releases energy and performs work to generate electricity during peak hours.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The system and method for improving the compression heat recovery rate of advanced adiabatic compressed air energy storage proposed in the present invention can effectively improve the compression heat recovery rate under the premise that the end difference of the heat exchanger remains unchanged and the heat exchange area is not significantly increased. The reason for this problem is that because the air flow rate in the compression and expansion processes of traditional compressed air energy storage is equal, due to the existence of the heat exchange end difference, the compression heat generated in the compression process cannot be fully utilized in the expansion process. For example: the heat absorption of air from 35°C to 170°C before expansion is less than the heat release of air from 195°C to 40°C after compression - the compression heat. The excess compression heat cannot be used and can only be taken away by open cooling water, resulting in reduced system efficiency. In order to avoid this, the present invention uses the entrainment effect of the ejector in the process of energy release and heat exchange to increase the air flow entering the air turbine, and improves the utilization ratio of compression heat while keeping the air temperature rise before expansion unchanged, thereby improving system efficiency. In addition, for heat exchange on the compression side, the air temperature drop remains unchanged, so the total area of ​​the heat exchanger and the cooler remains basically unchanged; for heat exchange on the expansion side, the air temperature rise remains unchanged, and the heat exchange end difference of the cold and hot fluids remains unchanged, so the area of ​​the heat exchanger on the expansion side is only slightly increased. Therefore, the present invention can effectively improve the recovery rate of compression heat and improve system efficiency, that is, the electric-to-electric conversion efficiency, under the premise that the heat exchange end difference remains unchanged and the heat exchange area is not significantly increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Schematic diagram of the energy conversion process and loss links of the advanced adiabatic compressed air energy storage system.

[0033] Figure 2 It is a schematic diagram of the structure of the gas ejector and the airflow suction process of the present invention.

[0034] Figure 3 This is a schematic diagram of a system for improving the compression heat recovery rate of advanced adiabatic compressed air energy storage provided by the present invention.

[0035] Figure 4 The schematic diagram of the connection between the radiator and the first stage reheater in the present invention is shown in FIG. Figure 1 .

[0036] Figure 5 The schematic diagram of the connection between the radiator and the first stage reheater in the present invention is shown in FIG. Figure 2 .

[0037] Description of reference numerals:

[0038] 1. Low-temperature and low-pressure air; 2. Air compressor; 3. Synchronous motor; 4. High-temperature and high-pressure air; 5. Heat exchanger; 6. High-pressure and low-temperature air; 7. Air injection valve; 8. High-pressure air main pipe; 9. Air storage device; 10. Air release valve; 11. Air ejector; 12. Pressure measuring element; 13. Regulating valve; 14. Reheater; 15. High-temperature and high-pressure mixed gas transmission pipe; 16. Main gas regulating combined valve; 17. Air turbine; 18. Generator; 19. Low-temperature water storage tank; 20. High-pressure cold water main pipe; 21. Low-temperature circulating water pump; 22. High-pressure cold water a; 23. High-pressure hot water a; 24. High-pressure hot water main pipe; 25. High-temperature water storage tank; 26. High-temperature circulating water pump; 27. High-pressure hot water b; 28. High-pressure cold water b. DETAILED DESCRIPTION

[0039] In order to make the above-mentioned purposes, features and advantages of the embodiments of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention. All other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] The inventors found that the air ejector can use high-pressure air to suck low-pressure air, thereby increasing the air flow. Figure 2 As shown, the high-pressure air stored in the air storage chamber is used as the primary flow, and the air in the atmosphere (secondary flow) is sucked in through the suction effect, and finally a mixed flow is formed to increase the air flow entering the air turbine. At present, the ejector is widely used in the scientific research field of improving the efficiency of compressed air energy storage systems, and many patents and papers have been formed, such as being used at the outlet of the final compressor to increase the injection flow of the air storage chamber, and being used at the turbine inlet to maintain a constant turbine inlet pressure. However, in this study, increasing the turbine inlet air flow by using an ejector to increase the utilization rate of compression heat has not been studied. If the goal of this patent can be achieved, the efficiency of the compressed air energy storage system can be greatly improved while the end difference of the heat exchanger remains unchanged.

[0041] In view of this, the present invention provides a method and system for improving the compression heat recovery rate of advanced adiabatic compressed air energy storage, aiming to solve the problems raised in the technical background, and can effectively improve the compression heat recovery rate without significantly increasing the heat exchange area while keeping the heat exchanger end difference unchanged.

[0042] like Figure 2 to Figure 5 As shown, the present invention provides a system for improving the compression heat recovery rate of advanced adiabatic compressed air energy storage, including an air compression unit and an air turbine 17. The air compression unit compresses low-temperature and low-pressure air 1 to output high-temperature air for energy storage when valley power or wind and solar power generation resources are sufficient. The system also includes:

[0043] The energy storage and release unit includes a heat exchanger 5, a gas storage device 9, an ejector 11, a reheater 14, a low-temperature water storage tank 19 and a high-temperature water storage tank 25, wherein:

[0044] Each heat exchanger 5 is used for heat exchange and energy storage between the high-temperature air output by the air compression unit and the low-temperature liquid working medium. Its tube-side inlet is connected to the air compression unit through a pipeline, its tube-side outlet is connected to the air storage device 9 through a pipeline, its shell-side inlet is connected to the low-temperature water storage tank 19 through a pipeline and a low-temperature circulating water pump 21, and its tube-side outlet is connected to the high-temperature water storage tank 25 through a pipeline;

[0045] The emanator 11 is used to increase the air flow rate and improve the compression heat recovery ratio. The emanator 11 has a primary flow inlet, a secondary flow inlet and a mixed flow outlet. The primary flow inlet is connected to the air storage device 9 through a pipeline, and the secondary flow inlet is connected to the air, and is used to mix the low-temperature air sent in by the primary flow inlet with the air sent in by the secondary flow and flow out from the mixed flow outlet;

[0046] Each reheater 14 is used to release energy by exchanging heat between the gas flowing out of each mixed flow outlet and the high-temperature liquid working medium. Its gas inlet is connected to the mixed flow outlet through a pipeline, its gas outlet is connected to the air turbine 17 through a pipeline, its liquid inlet is connected to the high-temperature water storage tank 25 through a pipeline and a high-temperature circulating water pump 26, and its liquid outlet is connected to the low-temperature water storage tank 19 through a pipeline.

[0047] Specifically, there are multiple emanator extractors 11 and multiple reheaters 14, and the multiple emanator extractors 11 correspond to the multiple reheaters 14 one by one and are connected in series through pipelines. The multiple emanator extractors 11 correspond to the multiple reheaters 14 one by one and are connected in series through pipelines to increase the air flow rate at the air turbine inlet. Under the condition that the heat exchange end difference remains unchanged, more air can be recycled and more compression heat can be utilized.

[0048] Specifically, there are multiple emanators 11 and multiple reheaters 14, and the mixed flow outlets of multiple emanators 11 are connected to the same output pipeline, so that multiple emanators 11 are connected in parallel, and the gas inlet of each reheater 14 is connected to the output pipeline through a pipeline. Multiple emanators 11 are connected in parallel and then connected to each reheater 14 to increase the air flow rate at the air turbine inlet. Under the condition that the heat exchange end difference remains unchanged, more air can be recycled and more compression heat can be utilized.

[0049] Specifically, the emanator 11 is also provided with a controller, the secondary flow inlet is provided with a regulating valve 13, the mixed flow outlet of the emanator 11 is provided with a pressure measuring element 12, the controller is connected with the regulating valve 13 and the pressure measuring element 12, and is used to adjust the opening of the regulating valve 13 by the mixed flow outlet pressure obtained by the pressure measuring element 12;

[0050] When the measured value of the pressure measuring element 12 at the mixed flow outlet of the ejector 11 is lower than the target set value, the controller closes the regulating valve 13 to reduce the air intake of the ejector 11, thereby increasing the mixed flow outlet pressure of the ejector 11; when the measured value of the pressure measuring element 12 at the mixed flow outlet of the ejector 11 is higher than the target set value, the controller opens the regulating valve 13 to increase the air intake of the ejector 11, thereby reducing the mixed flow outlet pressure of the ejector 11.

[0051] By setting the pressure setting value of the controller and comparing the setting value with the value measured by the pressure measuring element 12, the opening of the valve 13 is controlled so that the ejector 11 can suck in an appropriate amount of air. Otherwise, the amount of sucked air may be inappropriate, resulting in too low turbine inlet pressure or too little sucked air.

[0052] Specifically, valves are provided on all pipelines; the pipelines serve to collect and distribute the working fluid (air / water), and the valves serve to transport the working fluid to the pipelines and distribute the working fluid to the outside.

[0053] Specifically, all air compression units include multiple air compressors 2 and multiple synchronous motors 3. The multiple air compressors 2 and the multiple synchronous motors 3 correspond to each other one by one and are coaxially connected through a coupling.

[0054] Specifically, the air turbine 17 is coaxially connected to the generator 18 for releasing energy during peak hours of electricity consumption to ensure the supply of electricity during peak hours of electricity consumption.

[0055] Specifically, the pipelines connected to the gas outlets of multiple reheaters 14 are connected in parallel and then fed into the air turbine 7. The purpose of this is that usually, both sides of the air turbine are evenly fed with air. If the number of reheaters is not equal to 2, it needs to be distributed into 2 routes before entering the air turbine.

[0056] The present invention provides a method for improving the compression heat recovery rate of advanced adiabatic compressed air energy storage. The method is based on a system for improving the compression heat recovery rate of advanced adiabatic compressed air energy storage, and comprises the following steps:

[0057] During energy storage: start the synchronous motor 3, and the air compressor 2, driven by the synchronous motor 3, compresses the low-temperature and low-pressure air 1 from the atmosphere, and the output high-temperature and high-pressure air is sent to the pipe side of the heat exchanger 5 through the pipeline. The high-pressure cold water in the low-temperature water storage tank 19 is sent to the shell side of the heat exchanger 5 through the pipeline and the low-temperature circulating water pump 21. In the heat exchanger 5, the high-temperature and high-pressure air and the high-pressure cold water a22 are exchanged for heat and energy storage. After the heat exchange, the high-temperature air becomes low-temperature and high-pressure air 6 and is stored in the air storage device 9. After the heat exchange, the high-pressure cold water 22 becomes high-pressure hot water a23 and is sent to the high-temperature water storage tank 11.

[0058] When releasing energy: the low-temperature and high-pressure air 6 in the gas storage device 9 is sent into the ejector 11 through the primary inlet, and the external air is sucked in through the secondary inlet, and the air is mixed in the ejector 11 and sent to the gas inlet of the reheater 14 through the mixed outlet of the ejector 11. The high-pressure hot water b in the high-temperature water storage tank 25 is sent into the reheater 14 through the high-temperature circulating water pump 26 and the pipeline, and the high-pressure hot water b exchanges heat with the mixed gas sent into the reheater 14 to release energy;

[0059] When the measured value of the mixed flow outlet of the emanator 11 is lower than the target set value, the controller 12 closes the regulating valve 13 to reduce the air intake of the emanator 11, thereby increasing the mixed flow outlet pressure of the emanator 11; when the measured value of the mixed flow outlet of the emanator 11 is higher than the target set value, the controller 12 opens the regulating valve 13 to increase the air intake of the emanator 11, thereby decreasing the mixed flow outlet pressure of the emanator 11;

[0060] The high-pressure and low-temperature mixed gas is converted into high-temperature and high-pressure gas and then fed into the air turbine 17 to drive the generator 18 to rotate, so as to output electric energy during peak hours of electricity consumption.

[0061] Specifically, the multiple synchronous motors 3 compress air to store energy during off-peak hours or when wind and solar power generation resources are sufficient, and the air turbine 17 releases energy and performs work to generate electricity during peak hours.

[0062] The present invention provides a specific embodiment, and the compressed air energy storage system provided in this embodiment has two independent processes when working. Based on a 300MW compressed air energy storage system, equipped with an emanator, the system process and the role of the emanator in improving compression heat recovery are explained.

[0063] (I) The first working process is energy storage during the period when valley electricity or “wind and solar” resources are sufficient.

[0064] During energy storage, low-temperature and low-pressure air 1 in the environment is sucked in by an air compressor 2, and the compressor is driven by a synchronous motor 3; the air becomes high-temperature and high-pressure air 4 after passing through the compressor, and is cooled by high-pressure cold water 22 in a heat exchanger 5 to form high-pressure and low-temperature air 6, which enters the high-pressure air main pipe 8 through an air injection valve 7 and is finally stored in an air storage device 9; the high-pressure cold water 22 comes from a low-temperature water storage tank 19, and the high-pressure cold water a22 in the low-temperature water storage tank 19 is pressurized and supplied to the heat exchanger 5 by a cold water circulation pump 21 through a high-pressure cold water main pipe 20; after heat exchange, the water temperature rises to become high-pressure hot water a23, which flows into a high-pressure hot water main pipe 24 and is stored in a high-temperature water storage tank 25, to be used to heat the low-temperature and high-pressure air from the air storage chamber during peak hours of electricity consumption. Unlike conventional compressed air energy storage, the present invention uses more high-pressure cold water in the heat exchange link to directly cool the high-temperature and high-pressure air 4 to the target value, thereby obtaining more high-pressure hot water 23 stored in the hot water tank, which can heat more air when the turbine is put into use; unlike traditional compressed air energy storage, it does not use too much open cooling water, resulting in a large amount of compression heat being forced to be discharged into the atmosphere and causing waste, thereby achieving the recovery of more compression heat.

[0065] (II) The second process is to release energy during peak hours of electricity consumption

[0066] This process uses an ejector 11 to increase the air flow rate and improve the compression heat recovery ratio.

[0067] When releasing energy, the high-temperature and low-pressure air 6 in the air storage device 9 is evenly distributed to each emanator 11 by the high-pressure air main pipe 8; the air release valve 10 is opened, and the high-pressure and low-temperature air 6 enters the emanator 11, and sucks in the outdoor air when flowing through quickly, and enters through the regulating valve 13; the regulating valve 13 can adjust the amount of air inhaled, when the outlet pressure of the emanator is lower than the target value, the controller 12 closes the regulating valve 13 to reduce the amount of air inhaled, thereby increasing the mixed flow outlet pressure of the emanator 11, when the measured value of the mixed flow outlet of the emanator 11 is higher than the target set value, the controller 12 opens the regulating valve 13 to increase the amount of air inhaled by the emanator 11, thereby reducing the mixed flow outlet pressure of the emanator 11;

[0068] After passing through the ejector 11, more air flows into the first-stage reheater 14, is heated to a high-temperature state 15 by the high-pressure hot water b27, and then enters the high-pressure air turbine 17 through the main gas regulating combined valve 6 to expand and do work, driving the generator 18 to generate electricity, thereby ensuring the power supply during peak hours; the high-pressure hot water b27 originates from the high-temperature water storage tank 25, and is pressurized by the hot water circulation pump 26 after passing through the high-pressure hot water main pipe 24 and supplied to the reheater 14; after heat exchange, the high-pressure hot water b27 becomes high-pressure cold water b28 and is stored in the low-temperature water storage tank 19.

[0069] Different from conventional compressed air energy storage, the present invention delivers more high-temperature and high-pressure air to the air turbine 17, thereby improving the working capacity of the air turbine 17. The increased air volume is derived from the suction effect of the ejector, and the increased heat comes from the more recovered compression heat.

[0070] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A system for improving the compression heat recovery rate of an advanced adiabatic compressed air energy storage system, comprising an air compression unit and an air turbine (17), characterized in that: The air compression unit compresses low-temperature and low-pressure air (1) to output high-temperature air for energy storage when valley power or wind and solar power generation resources are sufficient, and further comprises: An energy storage and release unit comprises a heat exchanger (5), a gas storage device (9), an ejector (11), a reheater (14), a low-temperature water storage tank (19) and a high-temperature water storage tank (25), wherein: Each heat exchanger (5) is used to perform heat exchange and energy storage between high-temperature air output by the air compression unit and a low-temperature liquid working medium, wherein the tube side inlet is connected to the air compression unit via a pipeline, the tube side outlet is connected to the air storage device (9) via a pipeline, the shell side inlet is connected to the low-temperature water storage tank (19) via a pipeline and a low-temperature circulating water pump (21), and the tube side outlet is connected to the high-temperature water storage tank (25) via a pipeline; The emanator (11) is used to increase the air flow rate and improve the compression heat recovery ratio. The emanator (11) has a primary flow inlet, a secondary flow inlet and a mixed flow outlet. The primary flow inlet is connected to the air storage device (9) through a pipeline, and the secondary flow inlet is connected to the air and is used to mix the low-temperature air sent in by the primary flow inlet with the air sent in by the secondary flow and flow the mixed flow outlet out. Each reheater (14) is used to release energy by heat exchange between the gas flowing out of each mixed flow outlet and the high-temperature liquid working medium. Its gas inlet is connected to the mixed flow outlet through a pipeline, its gas outlet is connected to the air turbine (17) through a pipeline, its liquid inlet is connected to the high-temperature water storage tank (25) through a pipeline and a high-temperature circulating water pump (26), and its liquid outlet is connected to the low-temperature water storage tank (19) through a pipeline.

2. The system for improving compression heat recovery rate of advanced adiabatic compressed air energy storage according to claim 1, characterized in that: There are a plurality of the emanator vacuum pumps (11) and a plurality of the reheaters (14), and the plurality of the emanator vacuum pumps (11) and the plurality of the reheaters (14) correspond one to one and are connected in series via pipelines.

3. The system for improving compression heat recovery rate of advanced adiabatic compressed air energy storage according to claim 1, characterized in that: There are multiple emanators (11) and multiple reheaters (14), and the mixed flow outlets of the multiple emanators (11) are connected to the same output pipeline, so that the multiple emanators (11) are connected in parallel, and the gas inlet of each reheater (14) is connected to the output pipeline through a pipeline.

4. The system for improving compression heat recovery rate of advanced adiabatic compressed air energy storage according to claim 1, characterized in that: The emanator (11) is also provided with a controller, the secondary flow inlet is provided with a regulating valve (13), the mixed flow outlet of the emanator (11) is provided with a pressure measuring element (12), the controller is connected to the regulating valve (13) and the pressure measuring element (12), and is used to adjust the opening of the regulating valve (13) by the mixed flow outlet pressure obtained by the pressure measuring element (12); When the measured value of the pressure measuring element (12) at the mixed flow outlet of the emanator (11) is lower than the target set value, the controller closes the regulating valve (13) to reduce the air intake amount of the emanator (11), thereby increasing the mixed flow outlet pressure of the emanator (11); when the measured value of the pressure measuring element (12) at the mixed flow outlet of the emanator (11) is higher than the target set value, the controller opens the regulating valve (13) to increase the air intake amount of the emanator (11), thereby decreasing the mixed flow outlet pressure of the emanator (11).

5. The system for improving compression heat recovery rate of advanced adiabatic compressed air energy storage according to claim 1, characterized in that: All of the pipelines are provided with valves.

6. The system for improving compression heat recovery rate of advanced adiabatic compressed air energy storage according to claim 1, characterized in that: All air compression units include a plurality of air compressors (2) and a plurality of synchronous motors (3), the plurality of air compressors (2) and the plurality of synchronous motors (3) correspond to each other one by one and are coaxially connected via a coupling.

7. The system for improving compression heat recovery rate of advanced adiabatic compressed air energy storage according to claim 1, characterized in that: The air turbine (17) is coaxially connected to the generator (18) and is used to release energy during peak power consumption periods to ensure power supply during peak power consumption periods.

8. The system for improving compression heat recovery rate of advanced adiabatic compressed air energy storage according to claim 1, characterized in that: The pipelines connected to the gas outlets of the multiple reheaters (14) are connected in parallel and then fed into the air turbine (7).

9. A method for improving the compression heat recovery rate of advanced adiabatic compressed air energy storage, characterized in that: The method is based on the system for improving the compression heat recovery rate of advanced adiabatic compressed air energy storage according to any one of claims 1 to 8, and comprises the following steps: During energy storage: the air compressor (2) is driven by the synchronous motor (3) to compress the low-temperature and low-pressure air (1) from the atmosphere, and the output high-temperature and high-pressure air is sent to the tube side of the heat exchanger (5) through a pipeline. The high-pressure cold water in the low-temperature water storage tank (19) is sent to the shell side of the heat exchanger (5) through a pipeline and a low-temperature circulating water pump (21). In the heat exchanger (5), the high-temperature and high-pressure air and the high-pressure cold water (22) are heat exchanged and energy is stored. After the heat exchange, the high-temperature air becomes low-temperature and high-pressure air (6) and is stored in the air storage device (9). After the heat exchange, the high-pressure cold water a (22) becomes high-pressure hot water a (23) and is sent to the high-temperature water storage tank (11); When releasing energy: the low-temperature high-pressure air (6) in the gas storage device (9) is sent into the ejector (11) through the primary inlet, and the external air is sucked in through the secondary inlet. After being mixed in the ejector (11), the mixed air is sent into the gas inlet of the reheater (14) through the mixed outlet of the ejector (11). The high-pressure hot water b (27) in the high-temperature water storage tank (25) is sent into the reheater (14) through the high-temperature circulating water pump (26) and the pipeline. The high-pressure hot water b (27) exchanges heat with the mixed gas sent into the reheater (14) to release energy; When the measured value of the mixed flow outlet of the emanator (11) is lower than the target setting value, the controller (12) closes the regulating valve (13) to reduce the air intake of the emanator (11), thereby increasing the pressure of the mixed flow outlet of the emanator (11); when the measured value of the mixed flow outlet of the emanator (11) is higher than the target setting value, the controller (12) opens the regulating valve (13) to increase the air intake of the emanator (11), thereby decreasing the pressure of the mixed flow outlet of the emanator (11); The high-pressure and low-temperature mixed gas is converted into high-temperature and high-pressure gas and then fed into an air turbine (17) to drive a generator (18) to rotate, so as to output electric energy during peak hours of electricity consumption.

10. The method for improving compression heat recovery rate of advanced adiabatic compressed air energy storage according to claim 9, characterized in that: The plurality of synchronous motors (3) compress air to store energy during off-peak hours or when wind and solar power generation resources are sufficient, and the air turbine (17) releases energy and performs work to generate electricity during peak hours.

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