Geothermal energy anti-freezing system for indirect air cooling tower of compressed air energy storage project and operation method
By using a geothermal energy antifreeze system, which combines a circulating water system with a geothermal heat exchange system, the problem of freezing damage to the indirect air-cooled tower of the compressed air energy storage power station in low-temperature environments has been solved, achieving stable heating and efficient operation.
Patent Information
- Application Number
- CN202511222534.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-29
- Publication Date
- 2025-11-21
AI Technical Summary
Indirect air-cooled towers in compressed air energy storage power stations are prone to freezing damage in low-temperature environments. Traditional anti-freezing measures are difficult to adapt to their intermittent operation characteristics, and solar heating is unstable and cannot meet the anti-freezing requirements.
A geothermal energy antifreeze system is adopted, which combines the circulating water system with the geothermal heat exchange system to provide stable heat using geothermal energy. Combined with temperature control and valve management, it ensures that the circulating water temperature is within a suitable range to prevent freezing.
It achieves stable antifreeze during intermittent operation of compressed air energy storage power stations, reduces operational difficulty, improves the efficiency of circulating water systems, and is highly adaptable, economical, and environmentally friendly.
Smart Images
Figure CN120991620A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of compressed air energy storage, in particular to a geothermal energy anti-freezing system for an indirect air cooling tower of a compressed air energy storage project and an operation method. BACKGROUND
[0002] With the rapid development of China's economy and the continuous deepening of technology research and development, the efficiency of compressed air energy storage systems has steadily risen. Compressed air energy storage power stations, with their large capacity, short construction period, long service life, strong technology integration, flexible site selection, and safety and environmental protection, have been widely promoted in the energy storage field and have become an important force in building new power systems. As water-saving cooling facilities, indirect air cooling towers are in line with the reality of the relatively scarce water resources in the northwest region of China, so they have been effectively applied in compressed air energy storage power stations in this region, providing important support for the stable operation of the power station.
[0003] Unlike the continuous operation mode of thermal power plants, the operation of compressed air energy storage power stations is divided into two working conditions, energy storage and power generation, and is in an intermittent and alternating state. This unique operating characteristic makes the indirect air cooling tower prone to freezing problems in low-temperature environments. The heat flow changes during working condition switching can easily cause a sudden temperature drop in the equipment inside the tower, which can cause freezing damage. The traditional anti-freezing measures for indirect air cooling towers include frequency adjustment of the fan, installation of louvers at the air inlet, and setting up an emergency water drainage system. These measures can still play a certain role in continuous operation of thermal power plants, but due to the discontinuity and uncertainty of the operation period of compressed air energy storage power stations, conventional anti-freezing measures are difficult to accurately adapt to the changes in working conditions in low-temperature conditions, and the actual application effect is not ideal.
[0004] Among various auxiliary anti-freezing energy supply methods, solar energy is a clean energy, but it has obvious shortcomings and limitations. It is greatly affected by natural conditions, and the alternating day and night results in unstable energy supply at night. Energy supply also decreases significantly in bad weather such as rain and snow, which cannot meet the anti-freezing needs that may occur at any time during the intermittent operation of compressed air energy storage power stations. At the same time, solar energy equipment requires a large area, which is limited in applicability in some complex terrain areas in the northwest region, and the cost of energy conversion and storage is high, which is not economically efficient. SUMMARY
[0005] The technical problem to be solved by the present application is to provide a geothermal energy anti-freezing system for an indirect air cooling tower of a compressed air energy storage project and an operation method. The purpose is to solve the problem of water anti-freezing of the indirect air cooling tower during the intermittent operation of the compressed air energy storage power station, avoid frequent water filling and draining of the indirect air cooling tower, reduce the operation difficulty, and improve the operation efficiency of the circulating water system.
[0006] In order to solve the above technical problems, the technical scheme adopted by the present application is: a geothermal energy anti-freezing system for an indirect air cooling tower of a compressed air energy storage project, comprising an indirect air cooling tower, a circulating water system and a venting system connected to the indirect air cooling tower, and a geothermal heat exchange system connected to the circulating water system.
[0007] Further improvement of the technical scheme of the present application is that the circulating water system connected to the indirect air cooling tower is specifically: a circulating pipeline is connected to the water outlet of the indirect air cooling tower, a seventh valve and a first thermometer are connected to the main body section of the circulating pipeline, a high-level water tank is arranged at a high position, a water tank pipeline is arranged at the bottom of the high-level water tank and connected to the main body section of the circulating pipeline, a circulating water pump is arranged on the main body section, a fourth valve and a fifth valve are arranged before and after the circulating water pump respectively, and the back section of the main body section of the circulating pipeline is a circulating pipeline backwater section connected to the water inlet of the indirect air cooling tower.
[0008] Further improvement of the technical scheme of the present application is that the venting system connected to the indirect air cooling tower is specifically: a venting water tank is arranged underground, a venting pipeline is arranged on the main body section of the circulating pipeline, a twelfth valve serving as a venting valve is arranged on the venting pipeline, a venting pipeline is also arranged on the circulating pipeline backwater section, a thirteenth valve serving as a venting valve is arranged on the venting pipeline, and the venting pipelines are all connected to the venting water tank, a water filling pump is arranged in the venting water tank, a water filling pipeline is connected to the water filling pump, a sixteenth valve is arranged on the water filling pipeline, and the water filling pipeline is connected to the main body section and the backwater section of the circulating pipeline respectively.
[0009] Further improvement of the technical scheme of the present application is that the venting water tank is internally provided with a fourth thermometer and an electric heating system.
[0010] Further improvement of the technical scheme of the present application is that the geothermal heat exchange system connected to the circulating water system is specifically: an auxiliary heat exchanger and a second thermometer are connected to the main body section of the circulating pipeline, a plate heat exchanger is connected to the main body section of the circulating pipeline at the rear side of the second thermometer, a first valve is arranged at the water inlet of the plate heat exchanger, a third thermometer and a second valve are arranged at the water outlet of the plate heat exchanger, and the water outlet is connected to the circulating pipeline backwater section; a production well and a recharge well are connected to the heat energy supply end of the plate heat exchanger through a pipeline, a deep well pump is arranged in the production well, a sixth thermometer and a fifteenth valve are arranged on the pipeline of the production well, and a fifth thermometer and a fourteenth valve are arranged on the pipeline of the recharge well.
[0011] Further improvement of the technical scheme of the present application is that a non-heat exchange pipeline is further connected to the main body section of the circulating pipeline in parallel with the plate heat exchanger, backwater can be returned to the indirect air cooling tower directly without heat exchange through the non-heat exchange pipeline, and a third valve is arranged on the non-heat exchange pipeline.
[0012] The further improvement of the technical scheme of the present application is that the underground equipment room is arranged, and the plate heat exchanger, the first valve, the second valve, the fourteenth valve, the fifteenth valve, the third thermometer, the fifth thermometer and the sixth thermometer are arranged in the underground equipment room.
[0013] The further improvement of the technical scheme of the present application is that the data of the thermometers are received, and the opening and closing of the valves are controlled by the PLC.
[0014] The further improvement of the technical scheme of the present application is that the plate heat exchanger is selected according to the flow and temperature of the geothermal water, the temperature of the recharge water, the running flow of the circulating water pump, the temperature rise of the circulating water and the plate heat exchange efficiency; the number and parameters of the production well and the deep well pump and the recharge well are determined according to the single well heat load, the single well water yield, the circulating water heat load and the plate heat exchanger parameters; the circulating water pump is a variable frequency pump, and the number of the pump is not less than 2, and one standby pump is arranged; the number of the production well, the deep well pump and the recharge well is not less than 2, and one standby well is arranged.
[0015] During the operation of the energy storage power station, the first valve, the second valve, the sixth valve, the seventh valve, the twelfth valve and the thirteenth valve are closed, the remaining valves are opened, the circulating water system is normally operated, and the production well, the deep well pump, the recharge well and the plate heat exchanger are not operated;
[0016] During the intermittent operation of the unit in winter, the third valve, the sixth valve, the seventh valve, the twelfth valve and the thirteenth valve are closed, the remaining valves are opened, the production well, the deep well pump, the recharge well and the plate heat exchanger are put into operation, at this time, the circulating water pump is operated at variable frequency, and the flow is 20% to 40% of the rated flow; the number of the deep well pump and the production well is adjusted, and the flow of the circulating pump is adjusted to control the circulating water temperature at the third thermometer in the range of 30 to 35 DEG C, and the circulating water temperature at the first thermometer in the range of 15 to 18 DEG C; when the geothermal heat exchange system fails, the twelfth valve and the thirteenth valve are opened to quickly discharge the water in the whole system to the underground emptying water tank, so that the whole system is not frozen;
[0017] During the winter maintenance, the twelfth valve and the thirteenth valve are opened to quickly discharge the water in the whole system to the underground emptying water tank; before the water filling after the winter maintenance, if the temperature at the fourth thermometer is higher than a certain temperature, the water filling pump is directly started, and the water in the underground emptying water tank directly enters the indirect air cooling tower; if the temperature at the fourth thermometer is lower than a certain temperature, the electric heating system of the emptying water tank is started to heat the water in the water tank to a certain temperature, and then the water filling pump is started.
[0018] The technical progress achieved by the application is that: the heat transfer and uniform distribution are realized through the heat exchange pipeline under the ground by introducing the ground heat exchange technology, the heat can be continuously and stably provided without being affected by the change of external weather, the anti-freezing heat demand during intermittent operation of the compressed air energy storage power station can be accurately matched, the ground heat exchange system is flexible to install and has strong adaptability to the terrain, a large area of space is not required, the energy consumption is low during operation, the maintenance cost is small, the operation characteristics of the power station are met, and the economy and environmental protection are considered. BRIEF DESCRIPTION OF DRAWINGS
[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.
[0020] Figure 1 is a structural schematic diagram of a geothermal energy anti-freezing system of the present application for an indirect air cooling tower of a compressed air energy storage project.
[0021] Among them, 1, first valve, 2, second valve, 3, third valve, 4, fourth valve, 5, fifth valve, 6, sixth valve, 7, seventh valve, 8, eighth valve, 9, ninth valve, 10, tenth valve, 11, eleventh valve, 12, twelfth valve, 13, thirteenth valve, 14, fourteenth valve, 15, fifteenth valve, 16, sixteenth valve, 17, first thermometer, 18, second thermometer, 19, third thermometer, 20, fourth thermometer, 21, fifth thermometer, 22, sixth thermometer, 23, indirect air cooling tower, 24, high water tank, 25, circulating water pump, 26, auxiliary machine heat exchanger, 27, plate heat exchanger, 28, recharge well, 29, production well, 30, emptying water tank, 31, water filling pump, 32, electric heating system. DETAILED DESCRIPTION
[0022] The present application will be further described in detail below in combination with embodiments:
[0023] As Figure 1As shown, it is a structural schematic diagram of a geothermal energy anti-freezing system for an indirect air cooling tower of a compressed air energy storage project, comprising a plurality of indirect air cooling towers 23, a circulating water system and a venting system are connected and arranged on the indirect air cooling tower 23, and a geothermal heat exchange system is connected and arranged on the circulating water system. In this embodiment, the number of indirect air cooling towers 23 is two, and the circulating water system connected and arranged on the indirect air cooling tower 23 is specifically: the outlet of the two indirect air cooling towers 23 is connected and arranged into a circulating pipeline through a pipeline, the pipeline at the outlet of the two indirect air cooling towers 23 is respectively provided with a ninth valve 9 and an eleventh valve 11, the circulating pipeline main body section is connected and arranged with a seventh valve 7 and a first thermometer 17, and a high-level water tank 24 is arranged at a high position. The bottom of the high-level water tank 24 is provided with a water tank pipeline connected into the circulating pipeline main body section, a circulating water pump 25 is arranged on the main body section, a fourth valve 4 and a fifth valve 5 are respectively arranged before and after the circulating water pump 25, and the rear section of the circulating pipeline main body section is a circulating pipeline backwater section connected into the water inlet of the indirect air cooling tower 23. In this embodiment, the circulating pipeline backwater section is divided into two sections connected into the two indirect air cooling towers 23, and an eighth valve 8 and a tenth valve 10 are respectively arranged on the two backwater sections.
[0024] The venting system connected and arranged on the indirect air cooling tower 23 is specifically: a venting water tank 30 is arranged underground, a venting pipeline is arranged on the circulating pipeline main body section, a twelfth valve 12 serving as a venting valve is arranged on the venting pipeline, and a venting pipeline is also arranged on the circulating pipeline backwater section, a thirteenth valve 13 serving as a venting valve is arranged on the venting pipeline, and the venting pipelines are all connected into the venting water tank 30. A water filling pump 31 is arranged in the venting water tank 30, a water filling pipeline is connected and arranged on the water filling pump 31, a sixteenth valve 16 is arranged on the water filling pipeline, and the water filling pipeline is connected to the main body section and the backwater section of the circulating pipeline respectively. The sixth valve 6 is arranged on the connected backwater section pipeline. The venting water tank 30 is internally provided with a fourth thermometer 20 and an electric heating system 32.
[0025] The geothermal heat exchange system connected on the circulating water system is specifically: the auxiliary heat exchanger 26 and the second thermometer 18 are connected on the main body section of the circulating pipeline, the plate heat exchanger 27 is connected on the main body section of the circulating pipeline at the rear side of the second thermometer 18, the first valve 1 is arranged at the water inlet of the plate heat exchanger 27, the third thermometer 19 and the second valve 2 are arranged at the water outlet, and the water outlet is connected into the circulating pipeline backwater section; the production well 29 and the recharge well 28 are connected on the heat energy providing end of the plate heat exchanger 27 through the pipeline, the production well is a geothermal production well, and the production well has geothermal water; the deep well pump is arranged in the production well, the sixth thermometer 22 and the fifteenth valve 15 are arranged on the pipeline of the production well, and the fifth thermometer 21 and the fourteenth valve 14 are arranged on the pipeline of the recharge well 28. The non-heat exchange pipeline parallel to the plate heat exchanger 27 is also connected on the main body section of the circulating pipeline, and the backwater can directly return to the indirect air cooling tower through the non-heat exchange pipeline without heat exchange, and the third valve 3 is arranged on the non-heat exchange pipeline. Since the plate heat exchanger is directly installed on the circulating water pipeline instead of the bypass pipeline, an underground equipment room is needed, and the plate heat exchanger, the first valve 1, the second valve 2, the fourteenth valve 14, the fifteenth valve 15, the third thermometer 19, the fifth thermometer 21 and the sixth thermometer 22 matched with the plate heat exchanger are arranged in the underground equipment room. The opening and closing of the valves are controlled by the PLC according to the data of the thermometers. The plate heat exchanger 27 is selected according to the flow and temperature of the geothermal water, the temperature of the recharge water, the operating flow of the circulating water pump, the temperature rise of the circulating water and the plate heat exchange efficiency and other parameters; the number and parameters of the production well 29, the deep well pump and the recharge well 28 are determined according to the single well heat load, the single well water yield, the circulating water heat load, the parameters of the plate heat exchanger 27, the number of the circulating water pump 25 is not less than 2, and one standby is arranged; the number of the production well 29, the deep well pump and the recharge well 28 is not less than 2, and one standby is arranged.
[0026] According to the above system, an operation method of a geothermal energy anti-freezing system for an indirect air cooling tower of a compressed air energy storage project is realized, and the specific steps are:
[0027] During the operation of the energy storage power station, the first valve 1, the second valve 2, the sixth valve 6, the seventh valve 7, the twelfth valve 12 and the thirteenth valve 13 are closed, the remaining valves are opened, the circulating water system is normally operated, and the production well 29, the deep well pump, the recharge well 28 and the plate heat exchanger 27 are not operated.
[0028] During the intermittent operation of the winter unit, the third valve 3, the sixth valve 6, the seventh valve 7, the twelfth valve 12 and the thirteenth valve 13 are closed, the remaining valves are opened, the production well 29, the deep well pump, the recharge well 28 and the plate heat exchanger 27 are put into operation, at this time the circulating water pump 25 is operated in frequency conversion, the flow rate is 20% to 40% of the rated flow rate; the circulating water temperature at the third thermometer 19 is controlled in the range of 30 to 35 DEG C by adjusting the operation number of the deep well pump and the production well 29 and the operation flow rate of the circulating pump 25, the circulating water temperature at the first thermometer 17 is controlled in the range of 15 to 18 DEG C, when the geothermal heat exchange system is in an accident, the twelfth valve 12 and the thirteenth valve 13 are opened to quickly discharge the water in the whole system to the underground blowoff tank 30, so that the whole system is not frozen;
[0029] During the winter maintenance, the twelfth valve 12 and the thirteenth valve 13 are opened to quickly discharge the water in the whole system to the underground blowoff tank 30; before the water filling after the winter maintenance, if the temperature at the fourth thermometer 20 is higher than a certain temperature, the water filling pump 31 is directly started, the water in the underground blowoff tank 30 directly enters the indirect air cooling tower 23; if the temperature at the fourth thermometer 20 is lower than a certain temperature, the electric heating system 32 of the blowoff tank 30 is started to heat the water in the tank to a certain temperature, and then the water filling pump 31 is started. In the embodiment, the certain temperature is designed as 18 DEG C.
[0030] The above-described embodiment is only used to describe the preferred embodiment of the present application, and does not limit the scope of the present application, under the premise of not departing from the design spirit of the present application, various modifications and improvements of the technical solution of the present application made by the ordinary skilled in the art should fall into the protection scope determined by the claims of the present application.
Claims
1. A geothermal energy antifreeze system for an indirect air-cooled tower in a compressed air energy storage project, characterized in that: It includes an indirect air-cooled tower (23), on which a circulating water system and an venting system are connected, and on which a geothermal heat exchange system is connected.
2. The geothermal energy antifreeze system for an indirect air-cooled tower in a compressed air energy storage project according to claim 1, characterized in that: The circulating water system connected to the indirect air-cooled tower (23) is as follows: a circulating pipe is connected to the outlet of the indirect air-cooled tower (23), a seventh valve (7) and a first thermometer (17) are connected to the main body of the circulating pipe, a high-level water tank (24) is set at a high position, a water tank pipe is set at the bottom of the high-level water tank (24), the water tank pipe is connected to the main body of the circulating pipe, a circulating water pump (25) is set on the main body, a fourth valve (4) and a fifth valve (5) are set before and after the circulating water pump (25), the rear section after the main body of the circulating pipe is the circulating pipe return section, and the circulating pipe return section is connected to the inlet of the indirect air-cooled tower (23).
3. A geothermal energy antifreeze system for an indirect air-cooled tower in a compressed air energy storage project according to claim 2, characterized in that: The venting system connected to the indirect air-cooled tower (23) is as follows: an venting water tank (30) is installed underground, an venting pipe is installed on the main section of the circulation pipe, and a twelfth valve (12) is installed on the venting pipe as a venting valve. Similarly, an venting pipe is installed on the return water section of the circulation pipe, and a thirteenth valve (13) is installed on the venting pipe as a venting valve. The venting pipes are all connected to the venting water tank (30). A water filling pump (31) is installed in the venting water tank (30). A water filling pipe is connected to the water filling pump (31), and a sixteenth valve (16) is installed on the water filling pipe. At the same time, the water filling pipe is connected to the main section and the return water section of the circulation pipe respectively.
4. A geothermal energy antifreeze system for an indirect air-cooled tower in a compressed air energy storage project according to claim 3, characterized in that: The emptied water tank (30) is equipped with a fourth thermometer (20) and an electric heating system (32).
5. A geothermal energy antifreeze system for an indirect air-cooled tower in a compressed air energy storage project according to claim 4, characterized in that: The geothermal heat exchange system connected to the circulating water system is as follows: an auxiliary heat exchanger (26) and a second thermometer (18) are connected to the main section of the circulating pipe. A plate heat exchanger (27) is connected to the main section of the circulating pipe behind the second thermometer (18). A first valve (1) is installed at the inlet of the plate heat exchanger (27), and a third thermometer (19) and a second valve (2) are installed at the outlet. The outlet is connected to the return water section of the circulating pipe. The heat supply end of the plate heat exchanger (27) is connected to a production well (29) and a reinjection well (28) through a pipeline. A deep well pump is installed in the production well. A sixth thermometer (22) and a fifteenth valve (15) are installed on the production well pipeline. A fifth thermometer (21) and a fourteenth valve (14) are installed on the reinjection well (28) pipeline.
6. A geothermal energy antifreeze system for an indirect air-cooled tower in a compressed air energy storage project according to claim 5, characterized in that: The main section of the circulating pipeline is also connected to a non-heat exchange pipeline that is in parallel with the plate heat exchanger (27). The return water can be returned directly to the indirect air-cooled tower through the non-heat exchange pipeline without heat exchange. A third valve (3) is connected to the non-heat exchange pipeline.
7. A geothermal energy antifreeze system for an indirect air-cooled tower in a compressed air energy storage project according to claim 6, characterized in that: An underground equipment room is provided, which contains a plate heat exchanger and a first valve (1), a second valve (2), a fourteenth valve (14), a fifteenth valve (15), a third thermometer (19), a fifth thermometer (21), and a sixth thermometer (22) that cooperate with the plate heat exchanger.
8. A geothermal energy antifreeze system for an indirect air-cooled tower in a compressed air energy storage project according to claim 7, characterized in that: It receives data from various thermometers and controls the opening and closing of various valves via PLC.
9. The geothermal energy antifreeze system for an indirect air-cooled tower in a compressed air energy storage project as described in claim 8 is characterized in that: the plate heat exchanger (27) is selected based on the geothermal water flow rate and temperature, the reinjection water temperature, the circulating water pump operating flow rate, the circulating water temperature rise and the plate heat exchange efficiency, etc., calculated and determined; the number and parameters of the production well (29), deep well pump and reinjection well (28) should be calculated and determined based on the single well heat load, single well water output, circulating water heat load and plate heat exchanger (27) parameters; the circulating water pump (25) is a variable frequency pump with no less than 2 units, and 1 unit is set as a spare; the number of production well (29), deep well pump and reinjection well (28) is no less than 2 units, and 1 unit is set as a spare.
10. A method for operating a geothermal energy antifreeze system for an indirect air-cooled tower in a compressed air energy storage project, used to drive the antifreeze system as described in any one of claims 1-9, characterized in that: Includes the following: During the operation of the energy storage power station, the first valve (1), the second valve (2), the sixth valve (6), the seventh valve (7), the twelfth valve (12) and the thirteenth valve (13) are closed, and the remaining valves are open. The circulating water system operates normally, and the production well (29), deep well pump, reinjection well (28) and plate heat exchanger (27) are not in operation. During the intermittent operation of the unit in winter, the third valve (3), the sixth valve (6), the seventh valve (7), the twelfth valve (12), and the thirteenth valve (13) are closed, and the remaining valves are opened. The production well (29), the deep well pump, the reinjection well (28), and the plate heat exchanger (27) are put into operation. At this time, the circulating water pump (25) is operated by frequency conversion, and the flow rate is 20% to 40% of the rated flow rate. By adjusting the number of deep well pumps and production wells (29) and the operating flow rate of the circulating water pump (25), the circulating water temperature at the third thermometer (19) is controlled within the range of 30 to 35°C, and the circulating water temperature at the first thermometer (17) is controlled within the range of 15 to 18°C. In the event of an accident in the geothermal heat exchange system, the twelfth valve (12) and the thirteenth valve (13) are opened to quickly drain the water in the entire system to the underground empty water tank (30) to ensure that the entire system does not freeze. During winter maintenance, the twelfth valve (12) and the thirteenth valve (13) are opened to quickly drain the water in the entire system to the underground venting tank (30). Before filling with water after the winter maintenance, if the temperature at the fourth thermometer (20) is higher than a certain temperature, the filling pump (31) is started directly, and the water in the underground venting tank (30) directly enters the indirect air-cooled tower (23). If the temperature at the fourth thermometer (20) is lower than a certain temperature, the electric heating system (32) of the venting tank (30) is started to heat the water in the tank to a certain temperature before the filling pump (31) is started.