Water-saving compressed air energy storage system

Abstract

The utility model discloses a water-saving compressed air energy storage system, which relates to the technical field of compressed air energy storage systems and comprises a to-be-cooled component heat exchanger and a cooling unit. The cooling unit comprises a dry cooling tower, a wet cooling tower, a first switch valve, a cooling liquid inlet pipe and a cooling liquid return pipe; a cooling medium circulates in the system, a high-temperature cooling medium is arranged in the cooling liquid return pipe, and a low-temperature cooling medium is arranged in the cooling liquid inlet pipe; the first switch valve is located on the second branch of the liquid return pipe. The water-saving compressed air energy storage system solves the technical problem that a compressed air energy storage system in the prior art is large in water consumption. Under the same cooling load, the scheme has the technical effect of small water consumption.

Description

Technical Field

[0001] The utility model relates to the technical field of compressed air energy storage systems, in particular to a water-saving compressed air energy storage system. Background Art

[0002] Compressed air energy storage technology is a technology that uses compressed air to store energy. It is currently considered by the industry to be one of the technologies suitable for GW-level large-scale power energy storage. Its main uses are power frequency regulation, voltage regulation, peak regulation, load balancing, static reserve and grid black start. The working principle of compressed air energy storage technology is that during the period of low electricity consumption, electric energy is used to compress air to high pressure and store it in a pressure vessel, that is, the electric energy is converted into the internal energy of the air and stored. During the peak period of electricity consumption, the high-pressure air is released from the air storage chamber and drives the expander to generate electricity.

[0003] In the process of implementing the utility model, the inventors found that there are at least the following problems in the prior art:

[0004] In order to ensure the efficient operation of the compressed air energy storage system, it is necessary to dissipate the low-grade waste heat in the system. Since the cooling tower has the advantage of large heat dissipation, the existing system uses a cooling tower to dissipate the heat of the system. In order to ensure the heat transfer efficiency of the compressed air energy storage, the system uses a wet cooling tower. In large-scale compressed air energy storage systems, due to the large demand for heat dissipation, the number of wet cooling towers has to be increased, which will lead to a significant increase in the water consumption of large-scale compressed air energy storage systems. In areas with water resource development and utilization control red lines, high water consumption will directly affect the promotion and application of compressed air energy storage technology in the area.

[0005] Based on this, how to reduce the water consumption of the system while ensuring the heat dissipation and heat transfer efficiency is a technical problem that needs to be solved urgently by technical personnel in this field. Utility Model Content

[0006] The utility model aims to provide a water-saving compressed air energy storage system with small water consumption.

[0007] To achieve this purpose, on the one hand, a water-saving compressed air energy storage system is provided, including a heat exchanger for a component to be cooled and a cooling unit; the cooling unit includes a dry cooling tower, a wet cooling tower, a first switch valve, a second switch valve, a cooling liquid inlet pipe, and a cooling liquid return pipe; a cooling medium circulates in the water-saving compressed air energy storage system, the cooling liquid return pipe contains the high-temperature cooling medium, and the cooling liquid inlet pipe contains the low-temperature cooling medium; the cooling liquid return pipe includes a first branch of the liquid return pipe and a second branch of the liquid return pipe; the cooling liquid inlet pipe includes a first branch of the liquid inlet pipe and a second branch of the liquid inlet pipe; a first switch valve is arranged on the second branch of the liquid return pipe; a second switch valve is arranged on the first branch of the liquid inlet pipe; when the outdoor dry-bulb temperature is lower than a predetermined value, the first switch valve is closed, and the second switch valve is opened The first switch valve is opened, the first branch of the return liquid pipe is connected to the liquid inlet of the dry cooling tower, the liquid outlet of the dry cooling tower is connected to the first branch of the liquid inlet pipe, and the cold side inlet of the heat exchanger of the component to be cooled is connected to the first branch of the liquid inlet pipe; when the outdoor dry-bulb temperature is higher than the predetermined value, the first switch valve is opened, the second switch valve is closed, the first branch of the return liquid pipe is connected to the liquid inlet of the dry cooling tower, and the liquid outlet of the dry cooling tower is connected to the first branch of the liquid inlet pipe; and the wet cooling tower provides cooling for the second branch of the return liquid pipe, and the low-temperature cooling medium after cooling enters the second branch of the liquid inlet pipe; the first branch of the liquid inlet pipe and the second branch of the liquid inlet pipe merge into the cooling liquid inlet pipe, and the cold side inlet of the heat exchanger of the component to be cooled is connected to the cooling liquid inlet pipe.

[0008] Furthermore, the wet cooling tower is an open wet cooling tower.

[0009] Furthermore, it also includes a cooling heat exchanger, wherein the hot side inlet of the cooling heat exchanger is connected to the second branch of the liquid return pipe, and the hot side outlet of the cooling heat exchanger is connected to the second branch of the liquid inlet pipe.

[0010] Furthermore, the wet cooling tower includes a sprayer and a cold water pool, the cold water pool is located at the bottom of the wet cooling tower, and the sprayer is located above the cold water pool; the cold side outlet of the cooling heat exchanger is connected to the inlet of the sprayer, and the cold side inlet of the cooling heat exchanger is connected to the cold water pool.

[0011] Furthermore, the cold side outlet of the cooling heat exchanger is connected to the cold water pool through a pipeline, and a spray water pump is arranged on the pipeline.

[0012] Furthermore, the heat exchanger of the component to be cooled includes a waste heat exchanger, the cold side inlet of the waste heat exchanger is connected to the cooling liquid inlet pipe through a bypass; the cold side outlet of the waste heat exchanger is connected to the cooling liquid return pipe; the hot side inlet of the waste heat exchanger is connected to the hot side outlet of the expander heat exchanger, and the hot side outlet of the waste heat exchanger is connected to the inlet of the cold storage tank.

[0013] Furthermore, a third switch valve is provided on the bypass between the cold side inlet of the waste heat exchanger and the cooling liquid inlet pipe.

[0014] Furthermore, the heat exchanger for the component to be cooled also includes an equipment cooling heat exchanger, and the cold side of the equipment cooling heat exchanger is used to provide cooling to the equipment in the system; the cold side inlet of the equipment cooling heat exchanger is connected to the cooling liquid inlet pipe, and the cold side outlet of the equipment cooling heat exchanger is connected to the cooling liquid return pipe.

[0015] Furthermore, the wet cooling tower is a closed wet cooling tower.

[0016] Furthermore, the closed wet cooling tower includes a sprayer, a coil heat exchanger and a cold water pool; the coil heat exchanger is located between the sprayer and the cold water pool, and the cold water pool is located at the bottom of the closed wet cooling tower; the inlet of the sprayer and the outlet of the cold water pool are connected through a cooling pipe, and a spray water pump is provided on the cooling pipe, and the spray water pump is located at the outlet of the cold water pool; the second branch of the return liquid pipe is connected to the liquid inlet of the coil heat exchanger, and the liquid outlet of the coil heat exchanger is connected to the second branch of the liquid inlet pipe.

[0017] One of the above technical solutions has the following advantages or beneficial effects:

[0018] The water-saving compressed air energy storage system includes a heat exchanger for a component to be cooled and a cooling unit. The cooling unit is used to provide cooling to the heat exchanger for the component to be cooled. A cooling medium circulates in the system. The cooling unit includes a dry cooling tower, a wet cooling tower, a first switch valve, a second switch valve, a cooling liquid inlet pipe, and a cooling liquid return pipe. Among them, the first switch valve is located on the second branch of the liquid return pipe, and the second switch valve is located on the first branch of the liquid inlet pipe. The opening and closing of the first switch valve and the second switch valve are determined by the outdoor dry bulb temperature, and the predetermined value of the system is determined according to the parameters of the dry cooling tower.

[0019] When the outdoor dry-bulb temperature is lower than the predetermined value, the first switch valve is closed and the second switch valve is opened. The high-temperature cooling medium is recooled through the dry cooling tower, flows out from the first branch of the liquid inlet pipe and enters the cold side of the heat exchanger of the component to be cooled. The hot side of the heat exchanger of the component to be cooled is connected to the component to be cooled, and the cooling medium recooled by the dry cooling tower cools the component to be cooled. When the outdoor dry-bulb temperature is higher than the predetermined value, the first switch valve is opened and the second switch valve is closed. At this time, the high-temperature cooling medium is first cooled by the dry cooling tower, then cooled by the wet cooling tower, and finally merged into the cooling liquid inlet pipe through the second branch of the liquid inlet pipe, and then enters the cold side of the heat exchanger of the component to be cooled, which is used to provide cooling for the component to be cooled. At this time, the cooling medium is recooled by the dry cooling tower and the wet cooling tower together.

[0020] In summary, this solution opens the dry cooling tower and the wet cooling tower at the same time when the outdoor dry bulb temperature is higher than the preset value, and closes the wet cooling tower and opens the dry cooling tower when the outdoor dry bulb temperature is lower than the preset value. Since the cooling process of the dry cooling tower itself is cooling through air flow without cooling water, under the same cooling load, the water consumption of the compressed air energy storage system of this solution will be greatly reduced, which has the effect of saving water and is a water-saving compressed air energy storage system. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural flow diagram of the water-saving compressed air energy storage system in Example 1;

[0022] Figure 2 It is a structural flow diagram of the water-saving compressed air energy storage system in Example 2.

[0023] In the figure: 11-dry cooling tower; 12-wet cooling tower; 121-sprayer; 122-spray water pump; 123-coil heat exchanger; 124-cooling pipe; 13-first switch valve; 14-cooling liquid inlet pipe; 141-first branch of liquid inlet pipe; 142-second branch of liquid inlet pipe; 15-cooling liquid return pipe; 151-first branch of liquid return pipe; 152-second branch of liquid return pipe; 16-cooling heat exchanger; 17 second switch valve; 18-third switch valve; 22-first compressor; 23-first compressor Heat exchanger; 24-secondary compressor; 25-secondary compressor heat exchanger; 26-gas storage device; 27-first-stage expander heat exchanger; 28-first-stage expander; 29-second-stage expander heat exchanger; 31-waste heat exchanger; 32-cold storage tank; 33-heat storage tank; 34-hot water pump; 35-cold water pump; 41-cooling pump; 42-expander oil station heat exchanger; 43-compressor oil station heat exchanger; 44-expander motor heat exchanger; 45-compressor motor heat exchanger; 46-heat exchanger for components to be cooled. DETAILED DESCRIPTION

[0024] In order to make the technical problems solved by the utility model, the technical solutions adopted and the technical effects achieved clearer, the technical solutions of the embodiments of the utility model will be further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the utility model. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0025] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0027] Embodiment 1:

[0028] like Figure 1 As shown, the water-saving compressed air energy storage system includes a heat exchanger 46 of the component to be cooled and a cooling unit, and the cooling unit is used to provide coldness to the heat exchanger 46 of the component to be cooled. The cooling unit includes a dry cooling tower 11, a wet cooling tower 12, a first switch valve 13, a first switch valve 17, a cooling liquid inlet pipe 14, and a cooling liquid return pipe 15. A cooling medium circulates in the water-saving compressed air energy storage system. The high-temperature cooling medium after one circulation of the system enters the cooling liquid return pipe 15, and the low-temperature cooling medium after recooling by the cooling unit enters the cooling liquid inlet pipe 14, and then enters the cold side inlet of the heat exchanger of the component to be cooled. The first switch valve 13 of the cooling unit is located on the second branch 152 of the liquid return pipe, and the second switch valve 17 is located on the first branch 141 of the liquid inlet pipe. The opening and closing of the first switch valve 13 and the second switch valve 17 are determined by the outdoor dry bulb temperature, which is measured by a temperature detector. The predetermined value of the system is determined according to the parameters of the dry cooling tower.

[0029] When the outdoor dry-bulb temperature is lower than the predetermined value, the first switch valve 13 is closed and the second switch valve 17 is opened. The first branch 151 of the liquid return pipe is connected to the liquid inlet of the dry cooling tower 11. Since the second switch valve 17 is opened, the liquid outlet of the dry cooling tower 11 is connected to the first branch 141 of the liquid inlet pipe. The low-temperature cooling medium flows out of the first branch 141 of the liquid inlet pipe. The cold side inlet of the heat exchanger 46 of the component to be cooled is connected to the first branch 141 of the liquid inlet pipe. The low-temperature cooling medium flowing out of the first branch 141 of the liquid inlet pipe enters the cold side inlet of the heat exchanger 46 of the component to be cooled. The hot side of the heat exchanger 46 of the component to be cooled is connected to the component to be cooled in the system, and the low-temperature cooling medium flowing out of the liquid outlet of the dry cooling tower 11 provides cooling for the component to be cooled in the system.

[0030] When the outdoor dry bulb temperature is higher than the predetermined value, the first switch valve 13 is opened and the second switch valve 17 is closed. The first branch 151 of the return liquid pipe is connected to the liquid inlet of the dry cooling tower 11. Due to the opening of the first switch valve 13, the liquid outlet of the dry cooling tower 11 is connected to the second branch 152 of the return liquid pipe. At this time, the high-temperature cooling medium is first cooled by the dry cooling tower, then cooled by the wet cooling tower, and finally enters the cooling liquid inlet pipe 14 through the second branch 142 of the liquid inlet pipe, and then enters the cold side of the heat exchanger of the component to be cooled, which is used to provide cooling for the component to be cooled. At this time, the cooling medium is recooled by the dry cooling tower and the wet cooling tower.

[0031] It should be noted that the dry cooling tower 11 refers to an existing dry cooling tower, which generates air flow through the air density difference inside and outside the tower of the dry cooling tower 11, and takes away the heat of the cooling medium through the air flow, thereby recooling the cooling medium of the compressed air energy storage system. The wet cooling tower 12 is a device that directly contacts the cooling water through air, reduces the temperature through the flow and evaporation of the cooling water, and then cools the cooling medium of the system.

[0032] Taking the preset value of 20°C as an example, the principle of the water-saving compressed air energy storage system of this embodiment is explained: when the outdoor dry-bulb temperature is higher than 20°C, the first switch valve 13 is opened and the second switch valve 17 is closed. The high-temperature cooling medium used in the system enters the liquid inlet of the dry cooling tower 11 through the first branch 151 of the return liquid pipe, and is cooled in the dry cooling tower 11 by the air density difference inside and outside the tower, becoming a medium-temperature cooling medium, and flows out from the liquid outlet of the dry cooling tower 11. Since the first switch valve 13 is opened, the medium-temperature cooling medium flowing out of the liquid outlet of the dry cooling tower 11 enters the wet cooling tower 12 again, and after passing through the wet cooling tower 12, it is reduced to a low-temperature cooling medium and enters the cooling liquid inlet pipe 14 through the second branch 142 of the liquid inlet pipe. When the outdoor dry-bulb temperature is lower than 20°C, the first switch valve 13 is closed and the second switch valve 17 is opened. The high-temperature cooling medium after use in the system enters the liquid path of the dry cooling tower 11 through the first branch 151 of the liquid return pipe, and is cooled in the dry cooling tower 11 by the air density difference inside and outside the tower, and becomes a low-temperature cooling medium. Since the second switch valve 17 is opened, the low-temperature cooling medium enters the cooling liquid inlet pipe 14 through the first branch 141 of the liquid inlet pipe. The cooling liquid inlet pipe is connected to the cold side inlet of the heat exchanger of the component to be cooled, and the heat exchanger of the component to be cooled is used to provide cooling for the system.

[0033] In the cooling system of the present embodiment, the wet cooling tower 12 is turned on only when the outdoor temperature is higher than the set temperature, and thus the opening time of the wet cooling tower 12 is limited in a year. Therefore, it is more water-saving than the compressed air energy storage system in the prior art. This effect will be more obvious in areas where the dry-bulb temperature is below the system's preset value for most of the year, and the system's preset value is determined by the parameters of the dry cooling tower 11. Therefore, after reasonably selecting the parameters of the dry cooling tower 11, the water consumption of the water-saving compressed air energy storage system of the present embodiment will be further reduced, and the water-saving effect will be more obvious under the same cooling load.

[0034] Furthermore, the wet cooling tower is an open wet cooling tower.

[0035] The cooling water in the existing open wet cooling tower 12 is easily contaminated. If the contaminated cooling water enters the system, it will cause the pipes in the system to be blocked. Furthermore, the present embodiment also provides a cooling heat exchanger 16, the hot side inlet of the cooling heat exchanger 16 is connected to the second branch 152 of the return pipe, and the hot side outlet of the cooling heat exchanger 16 is connected to the second branch 142 of the liquid inlet pipe. Cooling water circulates in the open wet cooling tower 12 of the present embodiment, and the circulation of the cooling water and the cooling medium of the system are respectively in two circulation loops. The cooling water only circulates inside the open wet cooling tower 12, and the cooling medium circulates inside the water-saving compressed air energy storage system. The cooling medium of the system circulates in the hot side of the cooling heat exchanger 16, and the cold side of the cooling heat exchanger 16 provides cooling through the open wet cooling tower 12. In this embodiment, since the cooling heat exchanger 16 is provided to separate the circulation of cooling water in the open wet cooling tower 12 from the circulation of the cooling medium in the system, the diameter of the circulation pipeline of the cooling medium in the system remains unchanged. By increasing the pipeline diameter of the cold circuit of the cooling heat exchanger 16, blockage of the pipeline in the system can be avoided.

[0036] Furthermore, the open wet cooling tower 12 includes a sprayer 121 and a cold water pool. The cold water pool is located at the bottom of the open wet cooling tower 12, and the sprayer 121 is located above the cold water pool. The cold side inlet of the cooling heat exchanger 16 is connected to the inlet of the sprayer 121, and the cold side outlet of the cooling heat exchanger 16 is connected to the cold water pool. The cold side of the cooling heat exchanger 16 exchanges heat with the hot side of the cooling heat exchanger 16, so that the cooling medium of the internal system at the hot side outlet of the cooling heat exchanger 16 is recooled. The coolant at the cold side outlet of the cooling heat exchanger 16 is connected to the inlet of the sprayer 121, enters the open wet cooling tower 12 through the sprayer 121, and cools the coolant in the open wet cooling tower 12 through evaporative heat transfer with the air. The cooled cooling water is collected in the cold water pool for circulation in the open wet cooling tower 12.

[0037] Furthermore, the cooling medium uses water, preferably desalted water or purified water, which has low impurity content, is not prone to rust, and has low operating costs.

[0038] Furthermore, the cold side outlet of the cooling heat exchanger 16 is connected to the cold water pool through a pipeline, and a spray water pump 122 is provided on the pipeline to provide power for the circulation of the open wet cooling tower 12 .

[0039] The water-saving compressed air energy storage system in this embodiment includes a compressor, a compressor heat exchanger, an air storage device 26, an expander heat exchanger, a stage expander, a cold storage tank 32 and a heat storage tank 33. The energy storage process is as follows: the outside air enters the inlet of the first-stage compressor 22, generates compression heat after being compressed, and the compressed air flowing out of the outlet of the first-stage compressor 22 enters the hot side of the first-stage compressor heat exchanger 23. In the first-stage compressor heat exchanger 23, the heat storage medium on the cold side of the first-stage compressor heat exchanger 23 is cooled down, and the compression heat is temporarily stored in the heat storage medium. The heat storage medium on the cold side of the first-stage compressor heat exchanger 23 is provided by the cold storage tank 32. The heat storage medium flowing out of the cold storage tank 32 enters the cold side of the first-stage compressor heat exchanger 23 through the first pipeline. The outlet of the cold side of the first-stage compressor heat exchanger 23 is connected to the heat storage tank 33, and the heat storage medium after recovering the compression heat enters the heat storage tank 33 for temporary storage. The compressed air flowing out of the hot side outlet of the first-stage compressor heat exchanger 23 continues to enter the second-stage compressor 24, and the compressed air flowing out of the second-stage compressor 24 enters the hot path inlet of the second-stage compressor heat exchanger 25. The heat storage medium flowing out of the cold storage tank 32 enters the cold side inlet of the second-stage compressor heat exchanger 25 through the second pipeline, and the compression heat is recovered again through the second-stage compressor heat exchanger 25. The number of compressor stages and the number of compressor heat exchangers are determined by the requirements of the compressed air energy storage system. The compressed air on the hot side of the last-stage compressor heat exchanger enters the air storage device 26 for storage, and the compression heat at the cold side outlet of the last-stage compressor heat exchanger 23 is temporarily stored in the heat storage tank 33.

[0040] The energy release process of the water-saving compressed air energy storage system in this embodiment is as follows: the compressed air at room temperature or low temperature in the air storage device 26 enters the cold side of the first-stage expander heat exchanger 27, and the hot side inlet of the first-stage expander heat exchanger 27 is connected to the heat storage tank 33. The compressed air on its cold side is heated by the high-temperature heat storage medium in the heat storage tank 33, and the heated compressed air enters the inlet of the first-stage expander 28, flows out from the outlet of the first-stage expander 28 after expansion, and then enters the cold side of the second-stage expander heat exchanger 29, and is heated by the hot side of the second-stage expander heat exchanger 29.

[0041] Furthermore, the heat exchanger 46 of the component to be cooled includes a waste heat exchanger 31, the cold side inlet of the waste heat exchanger 31 is connected to the cooling liquid inlet pipe 14 through a bypass; the hot side inlet of the waste heat exchanger 31 is connected to the hot side outlet of the expander heat exchanger, and the hot side outlet of the waste heat exchanger 31 is connected to the inlet of the cold storage tank 32. In the above energy release process, the low-temperature heat storage flowing out of the hot side outlet of the first-stage expander heat exchanger 27 and the low-temperature heat storage flowing out of the hot side outlet of the second-stage expander heat exchanger 29 enter the hot side inlet of the waste heat exchanger 31. The cold side inlet of the waste heat exchanger 31 is connected to the cooling liquid inlet pipe 14 of the cooling unit, and the cooling capacity of the cooling unit ensures that the temperature of the heat storage medium entering the cold storage tank 32 is low enough, so that the compression heat can be recovered more efficiently in the energy storage stage. The cold side outlet of the waste heat exchanger 31 is connected to the cooling return liquid pipe 15, and the cooling unit is used for recooling.

[0042] Furthermore, a cold water pump 35 is provided on the outlet pipeline of the cold storage tank 32, and a hot water pump 36 is provided on the outlet pipeline of the heat storage tank 33. The cold water pump 35 and the hot water pump 36 provide power for cold storage and heat storage of the system.

[0043] Furthermore, the heat storage medium of the system uses water, preferably desalted water, so that the pipes in the system are not easy to rust. At the same time, the heat storage medium can also use other sensible heat storage medium materials.

[0044] Furthermore, the heat exchanger for the component to be cooled also includes an equipment cooling heat exchanger, the cold side of the equipment cooling heat exchanger is used to provide cooling to the equipment in the system; the cold side inlet of the equipment cooling heat exchanger is connected to the cooling liquid inlet pipe, and the cold side outlet of the equipment cooling heat exchanger is connected to the cooling liquid return pipe.

[0045] Furthermore, the equipment cooling heat exchanger includes an oil station heat exchanger and / or a motor heat exchanger. The oil station heat exchanger includes an expander oil station heat exchanger 42, the cold side inlet of the expander oil station heat exchanger 42 is connected to the cold side outlet of the waste heat exchanger 31, the cold side inlet of the expander oil station heat exchanger 42 is a low-temperature cooling medium, the hot side of the expander oil station heat exchanger 42 is connected to the expander oil station, and the hot side of the expander oil station heat exchanger 42 is the lubricating oil used by the expander, and the high-temperature lubricating oil flows in from the hot side inlet of the expander oil station heat exchanger 42, and after being cooled by the cold side of the expander oil station heat exchanger 42, it becomes a low-temperature lubricating oil and flows out from the hot side outlet of the expander oil station heat exchanger 42. Therefore, the water-saving compressed air energy storage system of this embodiment cools the expander oil station through the cooling unit.

[0046] Furthermore, the oil station heat exchanger includes a compressor oil station heat exchanger, the cold side inlet of the compressor oil station heat exchanger 43 is connected to the cold side outlet of the waste heat exchanger 31, the cold side inlet of the compressor oil station heat exchanger 43 is a low-temperature cooling medium, the hot side of the compressor oil station heat exchanger 43 is connected to the compressor oil station, the hot side of the compressor oil station heat exchanger 43 is the lubricating oil used by the compressor, the high-temperature lubricating oil flows in from the hot side inlet of the compressor oil station heat exchanger 43, after being cooled by the cold side of the compressor oil station heat exchanger 43, it becomes a low-temperature lubricating oil and flows out from the hot side outlet of the compressor oil station heat exchanger 43. Therefore, the water-saving compressed air energy storage system of this embodiment cools the compressor oil station through the cooling unit.

[0047] Furthermore, the motor heat exchanger includes an expander motor heat exchanger 44, and the cold side inlet of the expander motor heat exchanger 44 is connected to the cold side outlet of the waste heat exchanger 31, and the cold side inlet of the expander motor heat exchanger 44 is a low-temperature cooling medium. The expander motor can be air-cooled or water-cooled. If the expander motor is air-cooled, the hot side of the expander motor heat exchanger 44 is connected to the air-cooling channel of the expander motor, and the temperature of the expander motor is reduced after the cold side of the expander motor heat exchanger 44 is cooled. If the expander motor is water-cooled, the hot side of the expander motor heat exchanger 44 is connected to the water-cooling channel of the expander motor, and the temperature of the expander motor is reduced after the cold side of the expander motor heat exchanger 44 is cooled. Therefore, the water-saving compressed air energy storage system of this embodiment can cool the expander motor through the cooling unit.

[0048] Further, the motor heat exchanger includes a compressor motor heat exchanger 45, the cold side inlet of the compressor motor heat exchanger 45 is connected to the cold side outlet of the waste heat exchanger 31, and the cold side inlet of the compressor motor heat exchanger 45 is a low-temperature cooling medium. The compressor motor can be air-cooled or water-cooled. If the compressor motor is air-cooled, the hot side of the compressor motor heat exchanger 45 is connected to the air-cooling channel of the compressor motor. After the cold side of the compressor motor heat exchanger 45 is cooled, the temperature of the compressor motor is reduced. If the compressor motor is water-cooled, the hot side of the compressor motor heat exchanger 45 is connected to the water-cooling channel of the compressor motor. After the cold side of the compressor motor heat exchanger 45 is cooled, the temperature of the compressor motor is reduced. Therefore, the water-saving compressed air energy storage system of this embodiment can cool the compressor motor through the cooling unit.

[0049] Furthermore, a cooling pump 41 is provided on the pipeline between the cooling liquid inlet pipe 14 and the cold side inlet of the equipment cooling heat exchanger to provide power for the circulation of the cooling medium in the cold side of the oil station motor heat exchanger.

[0050] Furthermore, the cold side outlet of the equipment cooling heat exchanger is connected to the cooling liquid return pipe 15. After the cooling medium uses up its cooling capacity in the cold side of the equipment cooling heat exchanger, it enters the cooling liquid return pipe 15 of the cooling unit and is recooled by the cooling unit.

[0051] Furthermore, a third switch valve 18 is provided on the pipeline connecting the cold side inlet of the waste heat exchanger 31 and the cooling liquid inlet pipe 14. When the third switch valve 18 is closed, the low-temperature cooling medium flowing out of the cooling liquid inlet pipe 14 of the cooling unit directly enters the cold side of the equipment cooling heat exchanger. At this time, the waste heat exchanger 31 does not use the cooling unit to provide cooling capacity. When the third switch valve 18 is opened, the low-temperature cooling medium flowing out of the cooling liquid inlet pipe 14 of the cooling unit enters the cold side of the waste heat exchanger 31 and the cold side of the equipment cooling heat exchanger respectively. The opening and closing of the third switch valve 18 is determined by the temperature of the cold storage tank and the heat dissipation requirements of the equipment.

[0052] Embodiment 2:

[0053] This embodiment further provides a water-saving compressed air energy storage system, and the same parts as those in the first embodiment are not described in detail. Figure 2 In the water-saving compressed air energy storage system of this embodiment, the wet cooling tower is a closed wet cooling tower. The closed wet cooling tower has the advantages of high cooling efficiency, energy saving and environmental protection, and easy maintenance.

[0054] Furthermore, the closed wet cooling tower includes a sprayer 121, a coil heat exchanger 123 and a cold water pool, wherein the coil heat exchanger 123 is located between the sprayer 121 and the cold water pool, and the cold water pool is located at the bottom of the closed wet cooling tower; the inlet of the sprayer 121 and the outlet of the cold water pool are connected through a cooling pipe 124, and a spray water pump 122 is provided on the cooling pipe 124, and the spray water pump 122 is located at the outlet of the cold water pool. The second branch 152 of the return liquid pipe is connected to the liquid inlet of the coil heat exchanger 123, and the liquid outlet of the coil heat exchanger 123 is connected to the second branch 142 of the liquid inlet pipe.

[0055] In summary, the water-saving compressed air energy storage system provided in the first and second embodiments of the present invention opens the dry cooling tower and the wet cooling tower at the same time when the outdoor dry-bulb temperature is higher than a predetermined value, and closes the wet cooling tower and opens the dry cooling tower when the outdoor dry-bulb temperature is lower than a predetermined value. Since the cooling process of the dry cooling tower itself is cooling by air flow without cooling water, under the same cooling load, the water consumption of the compressed air energy storage system of this scheme will be greatly reduced, which has the effect of saving water and is a water-saving compressed air energy storage system. After calculation, even if the heat storage medium and the cooling medium in the system use water, the water consumption of the water-saving compressed air energy storage system provided by this embodiment is greatly reduced compared with the prior art, which meets the control red line of water resource development and utilization in most parts of my country.

[0056] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A water-saving compressed air energy storage system, characterized in that: It includes a heat exchanger for a component to be cooled and a cooling unit; the cooling unit includes a dry cooling tower, a wet cooling tower, a first switch valve, a second switch valve, a cooling liquid inlet pipe, and a cooling liquid return pipe; a cooling medium circulates in the water-saving compressed air energy storage system, the cooling liquid return pipe contains the high-temperature cooling medium, and the cooling liquid inlet pipe contains the low-temperature cooling medium; the cooling liquid return pipe includes a first branch of the liquid return pipe and a second branch of the liquid return pipe; the cooling liquid inlet pipe includes a first branch of the liquid inlet pipe and a second branch of the liquid inlet pipe; the second branch of the liquid return pipe is provided with a first switch valve; the first branch of the liquid inlet pipe is provided with a second switch valve; When the outdoor dry-bulb temperature is lower than a predetermined value, the first switch valve is closed, the second switch valve is opened, the first branch of the liquid return pipe is connected to the liquid inlet of the dry cooling tower, the liquid outlet of the dry cooling tower is connected to the first branch of the liquid inlet pipe, and the cold side inlet of the heat exchanger of the component to be cooled is connected to the first branch of the liquid inlet pipe; When the outdoor dry-bulb temperature is higher than a predetermined value, the first switch valve is opened, the second switch valve is closed, the first branch of the return liquid pipe is connected to the liquid inlet of the dry cooling tower, and the liquid outlet of the dry cooling tower is connected to the first branch of the liquid inlet pipe; and the wet cooling tower provides cooling for the second branch of the return liquid pipe, and the low-temperature cooling medium after cooling enters the second branch of the liquid inlet pipe; the first branch of the liquid inlet pipe and the second branch of the liquid inlet pipe merge into the cooling liquid inlet pipe, and the cold side inlet of the heat exchanger of the component to be cooled is connected to the cooling liquid inlet pipe.

2. The water-saving compressed air energy storage system according to claim 1, characterized in that: The wet cooling tower is an open wet cooling tower.

3. The water-saving compressed air energy storage system according to claim 2, characterized in that: It also includes a cooling heat exchanger, wherein the hot side inlet of the cooling heat exchanger is connected to the second branch of the liquid return pipe, and the hot side outlet of the cooling heat exchanger is connected to the second branch of the liquid inlet pipe.

4. The water-saving compressed air energy storage system according to claim 3, characterized in that: The wet cooling tower comprises a sprayer and a cold water pool, wherein the cold water pool is located at the bottom of the wet cooling tower, and the sprayer is located above the cold water pool; The cold side outlet of the cooling heat exchanger is communicated with the inlet of the sprayer, and the cold side inlet of the cooling heat exchanger is communicated with the cold water pool.

5. The water-saving compressed air energy storage system according to claim 4, characterized in that: The cold side outlet of the cooling heat exchanger is connected to the cold water pool through a pipeline, and a spray water pump is arranged on the pipeline.

6. The water-saving compressed air energy storage system according to claim 1, characterized in that: The heat exchanger for the component to be cooled comprises a waste heat exchanger, the cold side inlet of the waste heat exchanger is connected to the cooling liquid inlet pipe through a bypass; the cold side outlet of the waste heat exchanger is connected to the cooling liquid return pipe; The hot side inlet of the waste heat exchanger is communicated with the hot side outlet of the expander heat exchanger, and the hot side outlet of the waste heat exchanger is communicated with the inlet of the cold storage tank.

7. The water-saving compressed air energy storage system according to claim 6, characterized in that: A third switch valve is provided on the bypass between the cold side inlet of the waste heat exchanger and the cooling liquid inlet pipe.

8. The water-saving compressed air energy storage system according to claim 1, characterized in that: The heat exchanger for the component to be cooled also includes an equipment cooling heat exchanger, and the cold side of the equipment cooling heat exchanger is used to provide cooling to the equipment in the system; The cold side inlet of the equipment cooling heat exchanger is communicated with the cooling liquid inlet pipe, and the cold side outlet of the equipment cooling heat exchanger is communicated with the cooling liquid return pipe.

9. The water-saving compressed air energy storage system according to claim 1, characterized in that: The wet cooling tower is a closed wet cooling tower.

10. The water-saving compressed air energy storage system according to claim 9, characterized in that: The closed wet cooling tower includes a sprayer, a coil heat exchanger and a cold water pool; The coil heat exchanger is located between the sprayer and the cold water pool, and the cold water pool is located at the bottom of the closed wet cooling tower; the inlet of the sprayer and the outlet of the cold water pool are connected through a cooling pipe, and a spray water pump is provided on the cooling pipe, and the spray water pump is located at the outlet of the cold water pool; The second branch of the liquid return pipe is communicated with the liquid inlet of the coil heat exchange plate, and the liquid outlet of the coil heat exchange plate is communicated with the second branch of the liquid inlet pipe.

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