Compressed air energy storage power station circulating cooling water system and working method thereof

Abstract

According to the circulating cooling water system of the compressed air energy storage power station and the working method of the circulating cooling water system, waste heat of circulating water is utilized, freezing prevention in winter is achieved, and the purposes of saving energy and water are achieved. The main cooling tower is connected with the cooling tower water inlet main pipe and the pump set water inlet main pipe; the compression circulating pump, the expansion circulating pump and the idle circulating pump are all connected with the pump set water inlet main pipe and the circulating water supply main pipe. The circulating water supply mother pipe is connected with the compression energy storage equipment, and the circulating water return mother pipe is connected with the compression energy storage equipment; the circulating water supply main pipe and the circulating water return main pipe are both connected with the expansion energy release equipment; the circulating water supply main pipe and the idle water return pipe are both connected with the auxiliary machine equipment, and the idle water return pipe is connected with the cooling tower water inlet main pipe; the heat storage water tank is connected with the circulating water return main pipe and the cooling tower water inlet main pipe; the circulating water return branch pipe is connected with the circulating water return main pipe and the cooling tower water inlet main pipe; the anti-freezing circulating pump is connected with the pump set water inlet main pipe and the circulating water return main pipe; the auxiliary cooling tower is connected with the cooling tower water inlet main pipe and the pump set water inlet main pipe.

Description

Technical Field

[0001] The invention relates to a circulating cooling water system of a compressed air energy storage power station and a working method thereof. Background Art

[0002] In order to promote the realization of the goal, green, clean and renewable energy has been rapidly developed. By the end of 2023, the national installed power generation capacity will be 2.92 billion kilowatts, and non-fossil energy installed capacity will be about 1.57 billion kilowatts, accounting for 53.9%, historically exceeding thermal power installed capacity; among them, wind power and photovoltaic installed capacity will be 1.05 billion kilowatts, accounting for 85.3% of the total new installed capacity of non-fossil energy, and the proportion will continue to increase rapidly in the future. Renewable green electricity such as wind and light is intermittent and unstable, and energy storage technology can effectively solve the impact of large-scale access of intermittent renewable energy to the power grid on the safe and stable operation of the power system, and improve the flexibility and reliability of the power system. Among the many energy storage technologies, compressed air energy storage technology is considered to be one of the most promising large-scale new energy storage technologies. Its outstanding feature is that it can adapt to large-scale and long-term energy storage needs, and it has the advantages of relatively flexible site selection and short construction period. It has been rapidly developed in recent years and has become a project encouraged and supported by national policies.

[0003] At present, most compressed air energy storage power stations are distributed in the northwest of my country (such as Inner Mongolia, Xinjiang, etc.) where there are relatively rich wind and solar resources or salt caverns. However, these places are often water-scarce and cold in winter. The circulating water system of the power station requires not only water conservation, but also anti-freezing.

[0004] Due to its operating characteristics, the compressed air energy storage power station can be divided into the compression energy storage stage, the expansion energy release stage and the static idle stage. The amount of circulating water in each stage varies greatly, and the operating time varies. Take a 100MW / 400MW compressed air power station as an example: in the compression energy storage stage, in order to meet the compressor intake conditions and the temperature entering the cavitation, a large amount of circulating water is required, about 6000m 3 / h, and its running time is 6-8 hours; in the expansion and energy release stage, only the expander oil cooler and the generator air cooler are cooled, and the circulating water volume is ~1000m 3 / h, and its operating time is 3-4 hours; in the idle stage, only the cooling water of some small auxiliary equipment such as the compressor cranking cooler and the auxiliary equipment cooler of the whole plant that need to maintain the normal operation of the power station system is used. The circulating water volume is very low, only 200~300m 3 / h, and it runs continuously for 24 hours. Therefore, it is necessary to configure a suitable circulating water system to achieve energy-saving operation on the basis of meeting the system functions.

[0005] In addition, in order to meet the circulating water quality of the compressor and the heat exchange requirements with high-temperature compressed air (above 100°C) without scaling, the circulating water quality is required to be desalted water, and the system needs to adopt a closed circulation and closed cooling tower method, as shown in the Chinese patent with application number 201420217290.0 and the name of a water supply device in a compressed air energy storage system. This results in the cold winter in the north. If a conventional closed circulating water system is used, it is in a static idle stage, and the circulating water volume is low. During the standby period of the cooling tower, it is easy to cause the cooling tower coil system to freeze or block. In severe cases, the closed cooling tower is scrapped, causing the entire power station to be unable to operate. In order to achieve the antifreeze of the cooling tower, antifreeze is also added to the circulating water system, but the addition of this agent will significantly reduce the heat exchange effect of the circulating water. In order to achieve the purpose of heat exchange, it is necessary to increase the amount of cooling water, resulting in high operating costs of the circulating pump. In summer, it is necessary to vent the closed water with added agents, resulting in a large amount of water resources waste and processing fees.

[0006] Therefore, for compressed air energy storage power station equipment and closed cooling towers, in addition to ensuring the heat exchange efficiency of circulating water during high temperatures in summer, it is also necessary to ensure that the system can be antifreeze in winter. Summary of the invention

[0007] The purpose of the present invention is to overcome the above-mentioned deficiencies in the prior art and to provide a reasonably designed compressed air energy storage power station circulating cooling water system and its working method, which utilizes the waste heat of circulating water to achieve winter antifreeze and achieve the purpose of energy and water saving.

[0008] The technical solution adopted by the present invention to solve the above problems is: a circulating cooling water system of a compressed air energy storage power station, including a closed circulation system, the closed circulation system includes a circulating water supply main pipe, a circulating water return main pipe, a cooling tower water inlet main pipe, a main cooling tower and a pump group water inlet main pipe; the inlet of the main cooling tower is connected to the cooling tower water inlet main pipe, and the outlet is connected to the pump group water inlet main pipe; it is characterized in that it also includes a compression water inlet valve, a compression water return valve, an expansion water inlet valve, an expansion water return valve, an idle water inlet valve, an idle water return ... Return pipe, heat storage tank, water tank inlet pipe, water tank outlet pipe and antifreeze circulation pump; the closed circulation system also includes compression circulation pump, expansion circulation pump, idle circulation pump, circulation return water branch pipe, return water regulating valve and auxiliary cooling tower; the inlet of compression circulation pump, expansion circulation pump and idle circulation pump are all connected to the pump group water inlet main pipe, and the outlet is connected to the circulation water supply main pipe; the circulation water supply main pipe is connected to the water inlet of the compressed energy storage equipment of the compressed air energy storage power station through the compression water inlet valve, and the circulation return water main pipe is connected to the compressed air energy storage equipment through the compression water return valve. The outlet of the compressed energy storage device is connected; the circulating water supply main pipe is connected to the water inlet of the expansion energy release device of the compressed air energy storage power station through the expansion water inlet valve, and the circulating water return main pipe is connected to the water outlet of the expansion energy release device through the expansion water return valve; the circulating water supply main pipe is connected to the water inlet of the auxiliary equipment of the compressed air energy storage power station through the idle water inlet valve, the idle water return pipe is connected to the water outlet of the auxiliary equipment through the idle water return valve, and the idle water return pipe is connected to the cooling tower water inlet main pipe; the inlet of the hot water storage tank is connected to the circulating water supply main pipe through the water tank inlet pipe The loop water main pipe is connected, and a water tank inlet valve is arranged on the water tank inlet pipe; the outlet of the heat storage tank is connected to the cooling tower water inlet main pipe through the water tank outlet pipe, and a water tank outlet valve is arranged on the water tank outlet pipe; the circulating return water branch pipe is connected to the circulating return water main pipe and the cooling tower water inlet main pipe, and a return water regulating valve is arranged on the circulating return water branch pipe; the inlet of the antifreeze circulating pump is connected to the pump group water inlet main pipe, and the outlet is connected to the circulating return water main pipe; the inlet of the auxiliary cooling tower is connected to the cooling tower water inlet main pipe, and the outlet is connected to the pump group water inlet main pipe.

[0009] The main cooling tower described in the present invention is a dry-wet combined cooling tower; a wet section water inlet valve is arranged on the wet section inlet of the main cooling tower, and a wet section water outlet valve is arranged on the wet section outlet, the wet section inlet and the wet section outlet are both connected to the cooling tower water inlet mother pipe, the cooling tower water inlet mother pipe is connected to the dry section inlet of the main cooling tower, and the dry section outlet of the main cooling tower is the outlet of the main cooling tower; an intermediate isolation valve is arranged on the cooling tower water inlet mother pipe, and the intermediate isolation valve is located between the connection points of the wet section inlet and the wet section outlet and the cooling tower water inlet mother pipe.

[0010] The present invention is provided with upper air inlet louvers below the dry section of the main cooling tower, lower air inlet louvers below the wet section, an insulation chamber is provided at the fan platform at the top of the cooling tower, and an electric roller shutter is provided at the top air outlet.

[0011] The compression circulation pump described in the present invention is provided with a compression circulation pump water inlet valve on the inlet, and a compression circulation pump water outlet valve on the outlet; the expansion circulation pump is provided with an expansion circulation pump water inlet valve on the inlet, and an expansion circulation pump water outlet valve on the outlet; the idle circulation pump is provided with an idle circulation pump water inlet valve on the inlet, and an idle circulation pump water outlet valve on the outlet; the antifreeze circulation pump is provided with an antifreeze circulation pump inlet valve on the inlet, and an antifreeze circulation pump outlet valve on the outlet.

[0012] The hot water storage tank of the present invention is provided with a hot water storage tank electric heater.

[0013] The circulating water supply main pipe described in the present invention is provided with a water supply main pipe thermometer and a water supply main pipe flowmeter; the circulating water return main pipe is provided with a return water main pipe thermometer; a hot water storage tank thermometer; the cooling tower water inlet main pipe is provided with a cooling tower water inlet main pipe flowmeter and a cooling tower water inlet main pipe thermometer; and an outlet flowmeter is provided at the outlet of the antifreeze circulation pump.

[0014] The outlet of the main cooling tower of the present invention is provided with a main cooling tower water outlet valve and a cooling tower water outlet thermometer; the inlet of the auxiliary cooling tower is provided with an auxiliary cooling tower inlet valve, and the outlet is provided with an auxiliary cooling tower outlet valve.

[0015] The closed circulation system described in the present invention also includes a closed expansion water tank and a water supply pipeline, and the closed expansion water tank is connected to the water inlet main pipe of the pump group through the water supply pipeline.

[0016] A working method of a circulating cooling water system of a compressed air energy storage power station, characterized in that it comprises the following steps: (1) During the compression energy storage stage, the compression water inlet valve and the compression water return valve are opened, the circulation water inlet valve and the expansion water return valve are closed, and the compression circulation pump and the main cooling tower are started; the compression circulation pump sends the circulating water cooled by the main cooling tower to the compression energy storage equipment through the circulation water supply main pipe, and the heated circulating water returns to the main cooling tower through the circulation return water main pipe, the circulation return water branch pipe, and the cooling tower water inlet main pipe for cooling, and the cycle continues; at the same time, the water tank inlet valve and the water tank outlet valve are opened, the return water regulating valve is adjusted, and the circulation water supply main pipe injects high-temperature return water into the hot water storage tank; (2) During the expansion energy release stage, the compression circulation pump, compression water inlet valve and compression return valve are closed, the expansion stage circulation water inlet valve and expansion return valve are opened, the expansion circulation pump and the main cooling tower are started, and the expansion circulation pump sends the circulating water cooled by the main cooling tower to the expansion energy release equipment through the circulating water supply main pipe. The heated circulating water returns to the main cooling tower through the circulating return water main pipe, the circulating return water branch pipe and the cooling tower inlet water main pipe for cooling, and the cycle continues; at the same time, the water tank inlet valve is closed; (3) During the idle phase, the idle circulation pump and auxiliary cooling tower are turned on. The idle circulation pump delivers the circulating water cooled by the auxiliary cooling tower to the auxiliary equipment through the circulating water supply main pipe. The heated circulating water returns to the auxiliary cooling tower through the idle return pipe and the cooling tower inlet main pipe for cooling, and the cycle repeats. (4) In winter, when the outdoor temperature is below zero or the system needs antifreeze, the antifreeze circulation pump and the water tank outlet valve are turned on, and the hot water in the hot water storage tank enters the cooling tower water inlet main pipe to provide heat supplement to the closed circulation system; (5) In summer, by adjusting the water tank inlet valve and the water tank outlet valve, part of the waste heat of the circulating return water is stored in the heat storage tank; at the same time, during the static idle stage, the antifreeze circulation pump is turned on to send cooled circulating water into the circulating return water main pipe to cool the circulating return water.

[0017] The main cooling tower described in the present invention is a dry-wet combined cooling tower; a wet section water inlet valve is arranged on the wet section inlet of the main cooling tower, and a wet section water outlet valve is arranged on the wet section outlet, the wet section inlet and the wet section outlet are both connected to the cooling tower water inlet mother pipe, the cooling tower water inlet mother pipe is connected to the dry section inlet of the main cooling tower, and the dry section outlet of the main cooling tower is the outlet of the main cooling tower; an intermediate isolation valve is arranged on the cooling tower water inlet mother pipe, and the intermediate isolation valve is located between the connection points of the wet section inlet and the wet section outlet and the cooling tower water inlet mother pipe; and an upper air inlet louver is arranged below the dry section of the main cooling tower, and a lower air inlet louver is arranged below the wet section, an insulation chamber is arranged at the fan platform at the top of the cooling tower, and an electric roller shutter is arranged at the top air outlet; In the high temperature weather in summer, open the wet section water inlet valve and wet section water outlet valve, close the intermediate isolation valve, and realize the full load operation of the dry-wet combined cooling tower; In winter, as the outdoor temperature gradually decreases, in order to save water, the wet section of the dry-wet combined cooling tower is closed, that is, the wet section water inlet valve and wet section water outlet valve of the dry-wet combined cooling tower are closed, the middle isolation valve is opened, and only the dry type is operated. At the same time, in order to prevent freezing, the lower air inlet shutters are closed, the wet section coil is emptied, the heat taken away by the wet section coil is reduced, and the accidents of freezing and cracking are avoided; When anti-freezing is required during the idle stage, close the lower air inlet louvers and the top electric roller shutters to reduce the air cooling in the cooling tower.

[0018] When the present invention enters the compression energy storage stage or the expansion energy release stage, the idle circulation pump and the auxiliary cooling tower are shut down, but the idle water inlet valve and the idle water return valve are kept open.

[0019] Compared with the prior art, the present invention has the following advantages and effects: 1) Integrate the operating characteristics and circulating water volume differences of compressed air energy storage power stations at different stages, configure different circulating water supply and cooling modes, and reduce operating energy consumption while ensuring cooling functions. 2) By setting up antifreeze circulating pumps and hot water storage tanks, the waste heat of the closed circulating water system is fully utilized to supplement the system and achieve the purpose of energy saving and antifreeze of the system. The hot water storage tank can also play a role in preserving heat and balancing the system capacity. 3) Set up a separate auxiliary cooling tower and an idle circulating pump to meet the requirements of separate low-energy operation in summer and meet the requirements of circulating heat supply to the system in winter. 4) On the main cooling tower, a switching valve is set to achieve a multi-purpose function of one tower, achieve the effect of dry operation water saving and joint operation maximum capacity, and can also reduce heat loss and avoid freezing cracking in the bottom wet area of ​​the tower in winter. 5) Set an insulation room at the fan platform at the top of the cooling tower, and set an electric roller shutter at the top air outlet. Open the roller shutter during operation, and close the roller shutter and air inlet shutters during antifreeze and heat preservation to reduce the convective heat loss of the cooling tower and achieve self-insulation. 6) By adjusting the inlet valve and return regulating valve of the heat storage tank, the volume of the heat storage tank can be reasonably configured to reduce the amount of high-temperature circulating return water in the compression stage, thereby achieving the purpose of peak shaving and valley filling. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic structural diagram of an embodiment of the present invention.

[0021] Figure 2 for Figure 1 Schematic diagram of the structure of part A.

[0022] Figure 3 for Figure 1 Schematic diagram of the structure of part B.

[0023] Figure 4 for Figure 1 Schematic diagram of the structure of part C.

[0024] Figure 5 It is a structural schematic diagram of the main cooling tower of an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The present invention will be further described in detail below with reference to the accompanying drawings and by way of examples. The following examples are intended to explain the present invention but the present invention is not limited to the following examples.

[0026] 1. The embodiment of the present invention includes a closed circulation system, a compression stage valve group, an expansion stage valve group, a static idle stage cooling system and an antifreeze heat storage system.

[0027] The closed circulation system includes a compression circulation pump 1, a compression circulation pump inlet valve 1-1, a compression circulation pump outlet valve 1-2, an expansion circulation pump 2, an expansion circulation pump inlet valve 2-1, an expansion circulation pump outlet valve 2-2, an idle circulation pump 3, an idle circulation pump inlet valve 3-1, an idle circulation pump outlet valve 3-2, a circulation water supply main pipe 4, a water supply main pipe thermometer 5, a water supply main pipe flowmeter 6, a circulation return water main pipe 21, a return water main pipe thermometer 22, a circulation return water branch pipe 23, a return water regulating valve 24, a cooling tower inlet main pipe 28, a cooling tower inlet main pipe flowmeter 29, a cooling tower inlet main pipe thermometer 30, a main cooling tower 31, an auxiliary cooling tower 32, an auxiliary cooling tower inlet valve 32-1, an auxiliary cooling tower outlet valve 32-2, a pump group inlet main pipe 34, a cooling tower outlet water thermometer 33, a closed expansion water tank 35, a water supply pipeline 36 and a DCS centralized control system 37.

[0028] The compression stage valve group includes a compression water inlet valve 10 and a compression water return valve 11. The expansion stage valve group includes an expansion water inlet valve 14 and an expansion water return valve 15. The stationary idle stage cooling system includes an idle water inlet valve 18, an idle water return valve 19 and an idle water return pipe 20.

[0029] The antifreeze heat storage system includes a hot water storage tank 25, a water tank water inlet pipe 25-1, a water tank water inlet valve 25-2, a water tank water outlet valve 25-3, a water outlet pipe thermometer 25-4, a hot water storage tank electric heater 25-5, a hot water storage tank thermometer 25-6, a water tank water outlet pipe 25-7, an antifreeze circulation pump 26, an antifreeze circulation pump inlet valve 26-1, an antifreeze circulation pump outlet valve 26-2 and an outlet flow meter 27.

[0030] The inlet of the compression circulation pump 1 is provided with a compression circulation pump water inlet valve 1-1, and the outlet is provided with a compression circulation pump water outlet valve 1-2; the inlet of the compression circulation pump 1 is connected to the pump group water inlet main pipe 34, and the outlet is connected to the circulating water supply main pipe 4. The inlet of the expansion circulation pump 2 is provided with an expansion circulation pump water inlet valve 2-1, and the outlet is provided with an expansion circulation pump water outlet valve 2-2; the inlet of the expansion circulation pump 2 is connected to the pump group water inlet main pipe 34, and the outlet is connected to the circulating water supply main pipe 4. The inlet of the idle circulation pump 3 is provided with an idle circulation pump water inlet valve 3-1, and the outlet is provided with an idle circulation pump water outlet valve 3-2; the inlet of the idle circulation pump 3 is connected to the pump group water inlet main pipe 34, and the outlet is connected to the circulating water supply main pipe 4. The circulating water supply main pipe 4 is provided with a water supply main pipe thermometer 5 and a water supply main pipe flowmeter 6. The compression circulation pump 1 and the expansion circulation pump 2 should be equipped with at least one frequency converter, and multiple compression circulation pumps 1 should be installed. When the external weather temperature becomes lower and the circulating water volume decreases, energy saving can be achieved by frequency conversion or reducing the number of circulating water pumps.

[0031] The compressed energy storage equipment of the compressed air energy storage power station includes two compressors 7, an air-water cooler 8, and a compressor body oil station cooler 9. The inlet of the compressed water inlet valve 10 is connected to the circulating water supply main pipe 4, and the outlet is connected to the water inlet of the compressed energy storage equipment of the compressed air energy storage power station. The outlet of the compressed water return valve 11 is connected to the circulating water return main pipe 21, and the inlet is connected to the water outlet of the compressed energy storage equipment of the compressed air energy storage power station.

[0032] The expansion energy release equipment of the compressed air energy storage power station includes an expander oil cooler 12 and a generator air cooler 13. The inlet of the expansion water inlet valve 14 is connected to the circulating water supply main pipe 4, and the outlet is connected to the water inlet of the expansion energy release equipment of the compressed air energy storage power station. The outlet of the expansion return water valve 15 is connected to the circulating return water main pipe 21, and the inlet is connected to the water outlet of the expansion energy release equipment of the compressed air energy storage power station.

[0033] The auxiliary equipment of the compressed air energy storage power station includes a compressor crank cooler 16 and a whole plant auxiliary equipment cooler 17. The inlet of the idle water inlet valve 18 is connected to the circulating water supply main pipe 4, and the outlet is connected to the water inlet of the auxiliary equipment of the compressed air energy storage power station. The outlet of the idle return water valve 19 is connected to the idle return water pipe 20, and the inlet is connected to the water outlet of the auxiliary equipment of the compressed air energy storage power station. The idle return water pipe 20 is connected to the cooling tower water inlet main pipe 28.

[0034] A water return main pipe thermometer 22 is provided on the circulating water return main pipe 21 .

[0035] The hot water storage tank 25 is provided with a hot water storage tank electric heater 25-5 and a hot water storage tank thermometer 25-6. The inlet of the hot water storage tank 25 is connected to the circulating water return main pipe 21 through the water tank inlet pipe 25-1, and a water tank inlet valve 25-2 is provided on the water tank inlet pipe 25-1. The outlet of the hot water storage tank 25 is connected to the cooling tower inlet main pipe 28 through the water tank outlet pipe 25-7, and a water tank outlet valve 25-3 and an outlet pipe thermometer 25-4 are provided on the water tank outlet pipe 25-7. The water tank inlet pipe 25-1 is arranged at a high position of the water tank, and the water tank outlet pipe 25-7 is arranged at a low position of the water tank. At the same time, an insulation layer needs to be provided on the outside of the water tank to achieve effective replacement and insulation of high-temperature water in winter. The water tank inlet valve 25-2 is a regulating valve, which adjusts the water volume according to the system operation requirements. The capacity of the hot water storage tank 25 needs to be calculated to store an appropriate volume of hot water to ensure that the system does not freeze in winter.

[0036] One end of the circulating water return branch pipe 23 is connected to the circulating water return main pipe 21, and the other end is connected to the cooling tower water inlet main pipe 28. A water return regulating valve 24 is provided on the circulating water return branch pipe 23. By adjusting the opening of the water tank water inlet valve 25-2 and the water return regulating valve 24, the circulating water volume in the energy storage stage is diverted and compressed, the load of the main cooling tower 31 is reduced, and the system plays a role in peak shaving and valley filling.

[0037] A cooling tower water inlet main pipe flowmeter 29 and a cooling tower water inlet main pipe thermometer 30 are provided on the cooling tower water inlet main pipe 28 .

[0038] The inlet of the antifreeze circulation pump 26 is provided with an antifreeze circulation pump inlet valve 26-1, and the outlet is provided with an antifreeze circulation pump outlet valve 26-2; the inlet of the antifreeze circulation pump 26 is connected to the pump group water inlet main pipe 34, and the outlet is connected to the circulation return water main pipe 21. An outlet flow meter 27 is provided at the outlet of the antifreeze circulation pump 26. The antifreeze circulation pump 26 should adopt variable frequency operation to adapt to different outdoor weather conditions, and adjust the water replenishment amount of antifreeze water in combination with the temperature detected by the cooling tower outlet water thermometer 33.

[0039] The closed expansion water tank 35 is connected to the pump group water inlet main pipe 34 through the water supply pipe 36 to replenish water and maintain constant pressure in the system.

[0040] The outlet of the main cooling tower 31 is provided with a main cooling tower outlet valve 31 - 2 and a cooling tower outlet water thermometer 33 ; the inlet of the main cooling tower 31 is connected to the cooling tower water inlet main pipe 28 , and the outlet is connected to the pump group water inlet main pipe 34 .

[0041] The inlet of the auxiliary cooling tower 32 is provided with an auxiliary cooling tower inlet valve 32-1, and the outlet is provided with an auxiliary cooling tower outlet valve 32-2; the inlet of the auxiliary cooling tower 32 is connected to the cooling tower water inlet main pipe 28, and the outlet is connected to the pump group water inlet main pipe 34.

[0042] In order to save water, the main cooling tower 31 is a dry-wet combined cooling tower, and is composed of multiple groups. As the outdoor temperature changes, the cooling tower is opened or gradually closed. A wet section water inlet valve 31-1 is provided on the wet section inlet of the main cooling tower 31, and a wet section water outlet valve 31-4 is provided on the wet section outlet. The wet section inlet and the wet section outlet are both connected to the cooling tower water inlet main pipe 28. The cooling tower water inlet main pipe 28 is connected to the dry section inlet of the main cooling tower 31, and the dry section outlet of the main cooling tower 31 is the outlet of the main cooling tower 31. An intermediate isolation valve 31-3 is provided on the cooling tower water inlet main pipe 28, and the intermediate isolation valve 31-3 is located between the connection points of the wet section inlet and the wet section outlet and the cooling tower water inlet main pipe 28. A spray pump 31-5 is provided on the main cooling tower 31, and an upper air inlet louver 31-7 is provided below the dry section of the main cooling tower 31, and a lower air inlet louver 31-8 is provided below the wet section. An insulation room is provided at the fan platform at the top of the cooling tower, and an electric roller shutter 31-6 is provided at the top air outlet. When the equipment needs to be operated, the electric roller shutter 31-6 is opened. When anti-freezing is required in the static idle stage, the air inlet louver and the electric roller shutter 31-6 are closed to reduce the cooling of the incoming air in the cooling tower and realize the isolation and insulation of the tower.

[0043] For the auxiliary cooling tower 32, due to the small water volume, an ordinary wet closed cooling tower is selected. In the summer, when the high-temperature power station is in a static idle period, it is operated separately to save operating energy consumption; in winter, the auxiliary cooling tower 32 is shut down and emptied for anti-freezing.

[0044] 2. A working method of a circulating cooling water system of a compressed air energy storage power station, comprising the following steps: (1) According to the operating characteristics of the compressed air energy storage power station, during the compression energy storage stage, the closed-loop circulating water volume is the largest. The compression circulation pump inlet valve 1-1, the compression circulation pump outlet valve 1-2, the compression inlet valve 10 and the compression return valve 11 are opened, the expansion stage circulation inlet valve 14 and the expansion return valve 15 are closed, and the compression circulation pump 1 and the main cooling tower 31 are started; the compression circulation pump 1 sends the circulating water cooled by the main cooling tower 31 to the compression energy storage equipment cooling equipment through the circulating water supply main pipe 4, and the heated circulating water returns to the main cooling tower 31 through the circulating return water main pipe 21, the circulating return water branch pipe 23, and the cooling tower inlet main pipe 28 to cool down, and the cycle continues. At the same time, the water tank inlet valve 25-2 and the water tank outlet valve 25-3 are opened, the return water regulating valve 24 is adjusted, and the circulating water supply main pipe 4 injects high-temperature return water into the hot water storage tank 25 to replace the cold and hot water in the hot water storage tank 25 and store the residual heat in the circulating return water. When the DCS centralized control system 37 detects that the temperature fed back by the return water main pipe thermometer 22 is consistent with the temperature on the outlet pipe thermometer 25-4, the water tank inlet valve 25-2 can be closed to preserve the high-temperature water in the hot water storage tank 25. During the non-antifreeze period, the water tank inlet valve 25-2 can also be closed to maintain the hot water storage tank 25.

[0045] (2) During the expansion energy release stage, the system closes the compression circulation pump 1, the compression circulation pump water inlet valve 1-1, the compression circulation pump water outlet valve 1-2, the compression water inlet valve 10 and the compression water return valve 11, opens the expansion circulation pump water inlet valve 2-1, the expansion circulation pump water outlet valve 2-2, the expansion stage circulation water inlet valve 14 and the expansion water return valve 15, starts the expansion circulation pump 2 and the part of the main cooling tower 31 that matches the water volume, and the expansion circulation pump 2 sends the circulating water cooled by the main cooling tower 31 to the expansion energy release equipment cooling equipment through the circulating water supply main pipe 4. The heated circulating water returns to the main cooling tower 31 through the circulating water return main pipe 21, the circulating water return branch pipe 23 and the cooling tower water inlet main pipe 28 to cool down, and the cycle continues. At the same time, make sure that the water tank water inlet valve 25-2 remains closed.

[0046] (3) In the static idle stage, the idle circulating pump 3, the idle circulating pump inlet and outlet valve 3-1, the idle circulating pump outlet valve 3-2 and the auxiliary cooling tower 32 are turned on. The idle circulating pump 3 delivers the circulating water cooled by the auxiliary cooling tower 32 to the auxiliary equipment cooling equipment through the circulating water supply main pipe 4. The heated circulating water returns to the auxiliary cooling tower 32 through the idle return pipe 20 and the cooling tower inlet main pipe 28 for cooling. This cycle is repeated to achieve the matching of the circulating water volume and power in each stage, saving energy. When the system enters the compression energy storage stage or the expansion energy release stage, the idle circulating pump 3 and the auxiliary cooling tower 25 are shut down, but the idle inlet valve 18 and the idle return valve 19 are kept open to ensure that the auxiliary equipment of the entire plant is always in cooling operation.

[0047] (4) In winter, when the outdoor temperature is below zero or the system needs antifreeze, the antifreeze circulation pump 26 is turned on, the water tank outlet valve 25-3 is opened, and the hot water in the hot water storage tank 25 enters the cooling tower water inlet main pipe 28 to supplement heat to the closed circulation system; under extreme working conditions or when the idle stage is particularly long, the hot water in the hot water storage tank 25 cannot meet the entire heating demand, and the hot water storage tank electric heater 25-5 is turned on for electric heating supplement.

[0048] (5) In summer, by adjusting the water tank inlet valve 25-2 and the water tank outlet valve 25-3, part of the waste heat of the circulating return water is stored in the hot water storage tank 25, thereby reducing the operating load of the cooling tower; at the same time, during the static idle period, the antifreeze circulation pump 26 is turned on to send cooled circulating water to the circulating return water main pipe 21 to cool the circulating return water, thereby realizing the peak shaving and valley filling function of the cooling tower load.

[0049] (6) For the dry-wet combined cooling tower, in the summer with high temperature, open the wet section water inlet valve 31-1 and the wet section water outlet valve 31-4, close the intermediate isolation valve 31-3, and realize the full load operation of the dry-wet combined cooling tower. In winter, as the outdoor temperature gradually decreases, in order to save water, close the wet sections of the dry-wet combined cooling tower one by one, that is, close the wet section water inlet valve 31-1 and the wet section water outlet valve 31-4 of a single dry-wet combined cooling tower one by one, open the intermediate isolation valve 31-3, stop the spray pump 31-5, and only operate the dry type; at the same time, in order to prevent freezing, vent the wet section coil, gradually close the lower air inlet louver 31-8, reduce the heat taken away by the wet section coil, and avoid freezing and cracking accidents. When the entire dry-wet combined cooling tower is finally closed, ensure that the dry section is the last to exit operation to achieve savings. When the weather is below zero and anti-freezing is required during the idle period, the lower air inlet shutters 31-8 and the top electric roller shutters 31-6 are closed to reduce the air cooling in the cooling tower and achieve the isolation and heat preservation of the tower.

[0050] (7) During the antifreeze period, the high-temperature return water from the idle return pipe 20 is merged into the main cooling tower 31 system, and the auxiliary cooling tower 32 is shut down and emptied, waiting for the next non-antifreeze period to be replenished and started again. Of course, during the non-antifreeze period, the inlet and outlet valves of the hot water storage tank can also be closed, and the circulating return water can be directly fed into the cooling tower to maintain the hot water storage tank system.

[0051] In addition, it should be noted that the shapes and names of the parts and components of the specific embodiments described in this specification may be different, and the above content described in this specification is only an example of the structure of the present invention. All equivalent changes or simple changes made based on the structure, features and principles described in the patent concept of the present invention are included in the protection scope of the patent of the present invention. Technicians in the technical field of the present invention can make various modifications or supplements to the specific embodiments described or replace them in a similar manner, as long as they do not deviate from the structure of the present invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A circulating cooling water system for a compressed air energy storage power station, comprising a closed circulation system, wherein the closed circulation system comprises a circulating water supply main pipe, a circulating water return main pipe, a cooling tower water inlet main pipe, a main cooling tower and a pump group water inlet main pipe; the inlet of the main cooling tower is connected to the cooling tower water inlet main pipe, and the outlet is connected to the pump group water inlet main pipe; characterized in that: It also includes a compression inlet valve, a compression return valve, an expansion inlet valve, an expansion return valve, an idle inlet valve, an idle return valve, an idle return pipe, a heat storage tank, a water tank inlet pipe, a water tank outlet pipe and an antifreeze circulating pump; the closed circulation system also includes a compression circulating pump, an expansion circulating pump, an idle circulating pump, a circulating return branch pipe, a return regulating valve and an auxiliary cooling tower; the inlets of the compression circulating pump, the expansion circulating pump and the idle circulating pump are all connected to the pump group water inlet mother pipe, and the outlets are all connected to the circulating water supply mother pipe; the circulating water supply mother pipe is connected to the water inlet of the compressed energy storage equipment of the compressed air energy storage power station through the compression inlet valve, and the circulating return water mother pipe is connected to the water outlet of the compressed energy storage equipment through the compression return water valve; the circulating water supply mother pipe is connected to the water inlet of the expansion energy release equipment of the compressed air energy storage power station through the expansion inlet valve, and the circulating return water mother pipe is connected to the water outlet of the compressed energy storage equipment through the expansion return water valve It is connected to the water outlet of the expansion energy release device; the circulating water supply main pipe is connected to the water inlet of the auxiliary equipment of the compressed air energy storage power station through an idle water inlet valve, the idle return water pipe is connected to the water outlet of the auxiliary equipment through an idle return water valve, and the idle return water pipe is connected to the cooling tower water inlet main pipe; the inlet of the hot water storage tank is connected to the circulating return water main pipe through the water tank inlet pipe, and a water tank inlet valve is provided on the water tank inlet pipe; the outlet of the hot water storage tank is connected to the cooling tower water inlet main pipe through the water tank outlet pipe, and a water tank outlet valve is provided on the water tank outlet pipe; the circulating return water branch pipe is connected to the circulating return water main pipe and the cooling tower water inlet main pipe, and a return water regulating valve is provided on the circulating return water branch pipe; the inlet of the antifreeze circulating pump is connected to the pump group water inlet main pipe, and the outlet is connected to the circulating return water main pipe; the inlet of the auxiliary cooling tower is connected to the cooling tower water inlet main pipe, and the outlet is connected to the pump group water inlet main pipe.

2. The circulating cooling water system of the compressed air energy storage power station according to claim 1 is characterized in that: The main cooling tower is a dry-wet combined cooling tower; a wet section water inlet valve is arranged on the wet section inlet of the main cooling tower, and a wet section water outlet valve is arranged on the wet section outlet, the wet section inlet and the wet section outlet are both connected to the cooling tower water inlet mother pipe, the cooling tower water inlet mother pipe is connected to the dry section inlet of the main cooling tower, and the dry section outlet of the main cooling tower is the outlet of the main cooling tower; an intermediate isolation valve is arranged on the cooling tower water inlet mother pipe, and the intermediate isolation valve is located between the connection points of the wet section inlet and the wet section outlet and the cooling tower water inlet mother pipe.

3. The circulating cooling water system of the compressed air energy storage power station according to claim 1 is characterized in that: An upper air inlet louver is arranged below the dry section of the main cooling tower, a lower air inlet louver is arranged below the wet section, an insulation room is arranged at the fan platform at the top of the cooling tower, and an electric roller shutter is arranged at the top air outlet.

4. The circulating cooling water system of the compressed air energy storage power station according to claim 1 is characterized in that: The inlet of the compression circulation pump is provided with a compression circulation pump water inlet valve, and the outlet is provided with a compression circulation pump water outlet valve; the inlet of the expansion circulation pump is provided with an expansion circulation pump water inlet valve, and the outlet is provided with an expansion circulation pump water outlet valve; the inlet of the idle circulation pump is provided with an idle circulation pump water inlet valve, and the outlet is provided with an idle circulation pump water outlet valve; the inlet of the antifreeze circulation pump is provided with an antifreeze circulation pump inlet valve, and the outlet is provided with an antifreeze circulation pump outlet valve.

5. The circulating cooling water system of the compressed air energy storage power station according to claim 1 is characterized in that: The hot water storage tank is provided with a hot water storage tank electric heater.

6. The circulating cooling water system of the compressed air energy storage power station according to claim 1 is characterized in that: The circulating water supply main pipe is provided with a water supply main pipe thermometer and a water supply main pipe flowmeter; the circulating water return main pipe is provided with a return water main pipe thermometer; a hot water storage tank thermometer; the cooling tower water inlet main pipe is provided with a cooling tower water inlet main pipe flowmeter and a cooling tower water inlet main pipe thermometer; and an outlet flowmeter is provided at the outlet of the antifreeze circulation pump.

7. The circulating cooling water system of the compressed air energy storage power station according to claim 1 is characterized in that: The outlet of the main cooling tower is provided with a main cooling tower water outlet valve and a cooling tower water outlet thermometer; the inlet of the auxiliary cooling tower is provided with an auxiliary cooling tower inlet valve, and the outlet is provided with an auxiliary cooling tower outlet valve.

8. A working method of a circulating cooling water system of a compressed air energy storage power station according to any one of claims 1 to 7, characterized in that: The following steps are involved: (1) During the compression energy storage stage, the compression water inlet valve and the compression water return valve are opened, the circulation water inlet valve and the expansion water return valve are closed, and the compression circulation pump and the main cooling tower are started; the compression circulation pump sends the circulating water cooled by the main cooling tower to the compression energy storage equipment through the circulation water supply main pipe, and the heated circulating water returns to the main cooling tower through the circulation return water main pipe, the circulation return water branch pipe, and the cooling tower water inlet main pipe for cooling, and the cycle continues; at the same time, the water tank inlet valve and the water tank outlet valve are opened, the return water regulating valve is adjusted, and the circulation water supply main pipe injects high-temperature return water into the hot water storage tank; (2) During the expansion energy release stage, the compression circulation pump, compression water inlet valve and compression return valve are closed, the expansion stage circulation water inlet valve and expansion return valve are opened, the expansion circulation pump and the main cooling tower are started, and the expansion circulation pump sends the circulating water cooled by the main cooling tower to the expansion energy release equipment through the circulating water supply main pipe. The heated circulating water returns to the main cooling tower through the circulating return water main pipe, the circulating return water branch pipe and the cooling tower inlet water main pipe for cooling, and the cycle continues; at the same time, the water tank inlet valve is closed; (3) During the idle phase, the idle circulation pump and auxiliary cooling tower are turned on. The idle circulation pump delivers the circulating water cooled by the auxiliary cooling tower to the auxiliary equipment through the circulating water supply main pipe. The heated circulating water returns to the auxiliary cooling tower through the idle return pipe and the cooling tower inlet main pipe for cooling, and the cycle repeats. (4) In winter, when the outdoor temperature is below zero or the system needs antifreeze, the antifreeze circulation pump and the water tank outlet valve are turned on, and the hot water in the hot water storage tank enters the cooling tower water inlet main pipe to provide heat supplement to the closed circulation system; (5) In summer, by adjusting the water tank inlet valve and the water tank outlet valve, part of the waste heat of the circulating return water is stored in the heat storage tank; at the same time, during the static idle stage, the antifreeze circulation pump is turned on to send cooled circulating water into the circulating return water main pipe to cool the circulating return water.

9. The working method according to claim 8, characterized in that: The main cooling tower is a dry-wet combined cooling tower; a wet section water inlet valve is arranged on the wet section inlet of the main cooling tower, and a wet section water outlet valve is arranged on the wet section outlet, the wet section inlet and the wet section outlet are both connected to the cooling tower water inlet mother pipe, the cooling tower water inlet mother pipe is connected to the dry section inlet of the main cooling tower, and the dry section outlet of the main cooling tower is the outlet of the main cooling tower; an intermediate isolation valve is arranged on the cooling tower water inlet mother pipe, and the intermediate isolation valve is located between the connection points of the wet section inlet and the wet section outlet and the cooling tower water inlet mother pipe; and an upper air inlet louver is arranged below the dry section of the main cooling tower, and a lower air inlet louver is arranged below the wet section, an insulation chamber is arranged at the fan platform at the top of the cooling tower, and an electric roller shutter is arranged at the top air outlet; In the high temperature weather in summer, open the wet section water inlet valve and wet section water outlet valve, close the intermediate isolation valve, and realize the full load operation of the dry-wet combined cooling tower; In winter, as the outdoor temperature gradually decreases, in order to save water, the wet section of the dry-wet combined cooling tower is closed, that is, the wet section water inlet valve and wet section water outlet valve of the dry-wet combined cooling tower are closed, the middle isolation valve is opened, and only the dry type is operated. At the same time, in order to prevent freezing, the lower air inlet shutters are closed, the wet section coil is emptied, the heat taken away by the wet section coil is reduced, and the accidents of freezing and cracking are avoided; When anti-freezing is required during the idle stage, close the lower air inlet louvers and the top electric roller shutters to reduce the air cooling in the cooling tower.

10. The working method according to claim 8, characterized in that: When entering the compression energy storage stage or the expansion energy release stage, the idle circulation pump and the auxiliary cooling tower are shut down, but the idle water inlet valve and the idle water return valve remain open.

Images