Air drying device system and method for compressed air energy storage

Abstract

This invention provides an air drying device system and method for compressed air energy storage. The air drying device system utilizes an adsorption-type air drying device to dry the air during the compressed air energy storage process, effectively avoiding corrosion of various equipment and pipelines in the device system. Moreover, it makes reasonable use of the exhaust gas at the end of the air turbine and the waste heat of the heat storage medium, reducing the power consumption of the heat dissipation device and improving the energy utilization rate, which has the prospect of large-scale industrial application.

Description

Technical Field

[0001] This invention relates to the field of energy technology, and in particular to an air drying device system and method for compressed air energy storage. Background Technology

[0002] Compressed air energy storage, as a new type of energy storage technology with long-term, large capacity, and low cost, has the advantages of flexible site selection, safety and environmental protection. It can realize the consumption of renewable energy, peak shaving and valley filling, support grid stability, and provide comprehensive energy such as cooling, heating, electricity and industrial gas. This technology is receiving widespread attention.

[0003] CN112648076A discloses a compressed air energy storage system, including a compressed air energy storage subsystem, a compressed heat recovery subsystem, a gas storage subsystem, a compressed heat release subsystem, and a compressed air energy release subsystem. The compressed air energy storage subsystem is connected to the compressed heat recovery subsystem via pipelines. The compressed heat recovery subsystem is connected to the gas storage subsystem via pipelines. The gas storage subsystem is connected to the compressed heat release subsystem via pipelines. The compressed heat release subsystem is connected to the compressed air energy release subsystem via pipelines. An air temperature raising device is installed between the compressed heat release subsystem and the compressed air energy release subsystem. The compressed air energy storage subsystem is connected to the compressed heat recovery subsystem, and the compressed heat release subsystem utilizes compressed heat. Before the air enters the compressed air energy release subsystem, the air temperature raising device raises the temperature of the air at the inlet of the compressed air energy release subsystem. The air temperature raising device utilizes waste heat resources from industrial enterprises, thereby ensuring higher power generation.

[0004] CN103644095A discloses a novel method and apparatus for compressed air energy storage. This method and apparatus divides the variable power range of the input electrical energy into several levels, each power level corresponding to a pressure level of the compressed air energy storage system. When the input electrical power varies significantly, variable operating conditions are achieved by changing the compressed air pressure level of the compressed air energy storage system, and electrical energy is stored. When the input electrical power varies only slightly, the compressed air pressure level remains constant, and variable operating conditions are achieved by adjusting the compressed air flow rate, while electrical energy is stored. Compressed air at different pressures is stored separately using a constant-pressure storage method. Using this apparatus for compressed air energy storage ensures that even with large and frequent changes in the input electrical power, the main equipment of the system always operates near its rated operating conditions, thus greatly improving the energy storage efficiency of the energy storage system.

[0005] CN112096470A discloses a liquid compressed air energy storage peak-shaving system and method coupled with a heating system, which recovers the heat of air compression from the liquid compressed air energy storage system through the heating system. During the heating season, the heat of air compression is used to preheat the circulating water of the heating network, reducing the steam extraction flow rate of the unit for heating; during the non-heating season, the heat of air compression is recovered and utilized through condensate, thereby reducing the unit's energy consumption. By coupling the coal-fired unit's heating system with the liquid compressed air energy storage system, the overall operating efficiency of the system is improved. Compared with conventional liquid compressed air energy storage peak-shaving systems with heat storage devices, this system uses an air cooler to recover the heat of air compression into the unit's thermal cycle, eliminating the need for a heat storage system. This effectively improves the overall system operating efficiency and reduces the overall project investment.

[0006] However, the above-mentioned compressed air energy storage system does not take into account that after the compressed air is cooled, the dew point will rise and moisture will be released, which is not conducive to the inlet conditions of the next stage compressor and will also cause corrosion to the system equipment and pipelines.

[0007] Therefore, developing an air drying device system and method for compressed air energy storage to treat the moisture in the air is an urgent problem to be solved in compressed air energy storage systems. Summary of the Invention

[0008] In view of the problems existing in the prior art, the present invention provides an air drying device system and method for compressed air energy storage. By rationally arranging adsorption-type air drying devices in the compressed air energy storage system, it is possible to dry the air, avoid corrosion of equipment and pipelines, and utilize the waste heat of the medium in the compressed air energy storage system to regenerate the desiccant, thereby improving energy utilization efficiency.

[0009] To achieve this objective, the present invention adopts the following technical solution:

[0010] In a first aspect, the present invention provides an air drying device system for compressed air energy storage, the air drying device system comprising an air compressor, a cooling device, an air storage device, a heating device and an air turbine connected in sequence;

[0011] The air drying device system also includes an adsorption-type air drying device and a heat dissipation device; the adsorption-type air drying device includes an air intake pipe for the air to be dried, an exhaust pipe for the dried air, a first medium pipe, and a second medium pipe.

[0012] The adsorption-type air drying device is connected to an air compression device via a dry air exhaust pipe and to an air turbine via a first medium pipe.

[0013] Alternatively, the adsorption-type air drying device may be connected to the heating device via a first medium pipeline and to the heat dissipation device via a regeneration gas exhaust pipeline.

[0014] The air drying device system for compressed air energy storage described in this invention utilizes an adsorption-type air dryer to dry the air during the compressed air energy storage process, effectively preventing corrosion of various equipment and pipelines within the system. Furthermore, the adsorption-type air dryer employs physical adsorption, allowing for regeneration by heating the desiccant and releasing the adsorbed moisture. In this invention, an air turbine is connected to the adsorption-type air dryer via a first medium pipeline, utilizing the exhaust gas from the air turbine to regenerate the desiccant. Alternatively, a heating device is connected to the adsorption-type air dryer via the first medium pipeline, utilizing the high-temperature medium within the heating device to regenerate the desiccant. This air drying device system rationally utilizes the exhaust gas from the air turbine and the waste heat from the heat storage medium, reducing the power consumption of the heat dissipation device and improving energy efficiency, demonstrating promising prospects for large-scale industrial application.

[0015] The medium flowing in the first and second medium pipelines of the present invention includes gas discharged from an air turbine or heat storage medium discharged from a heating device.

[0016] Preferably, the number of air compressors is two or more, such as two, three, four or five.

[0017] Preferably, the number of cooling devices is the same as the number of air compression devices.

[0018] Preferably, an air handling unit consisting of an air compressor and a cooling unit connected in sequence is used as a group of air handling units, and the adsorption-type air drying unit is also disposed between the previous group of air handling units and the next group of air handling units along the airflow direction.

[0019] This invention fully considers the working pressure and temperature requirements of the adsorption air dryer. It uses an air compressor and a cooling device connected in sequence as a group of air handling devices. The adsorption air dryer is also set between the previous group of air handling devices and the next group of air handling devices along the air flow direction, so as to better utilize the adsorption air dryer to dry the air.

[0020] Preferably, the number of heating devices is the same as the number of air turbines.

[0021] Preferably, the number of air turbines is two or more, for example, two, three, four or five.

[0022] Preferably, the number of air turbines is the same as the number of air compressors.

[0023] Preferably, the air drying device system further includes a first heat storage medium storage device and a second heat storage medium storage device.

[0024] Preferably, the first thermal storage medium storage device is connected in sequence to the cooling device and the second thermal storage medium storage device.

[0025] Preferably, the second heat storage medium storage device is connected in sequence with the heating device, the heat dissipation device and the first heat storage medium storage device.

[0026] In a second aspect, the present invention also provides an air drying method for compressed air energy storage, wherein the air drying method employs the air drying device system for compressed air energy storage described in the first aspect; the air drying method includes:

[0027] When compressed air is stored, the air enters the adsorption-type air drying device through the air intake pipe to be dried, and after being dried, it passes through the air compression device and the cooling device in sequence before entering the air storage device for storage.

[0028] The heat generated during air compression is stored by the heat storage medium, which flows from the first heat storage medium storage device through the cooling device into the second heat storage medium storage device, storing the heat of compression during air compression.

[0029] Preferably, the air drying method further includes:

[0030] When compressed air releases energy, the compressed air in the air storage device is heated by the heating device and then enters the air turbine to do work and generate electricity. The exhaust gas from the air turbine enters the adsorption air dryer, and the waste heat of the exhaust gas is used to regenerate the desiccant.

[0031] The heat storage medium in the second heat storage medium storage device flows through the heating device and the heat dissipation device, and after releasing the stored compressed heat, it enters the first heat storage medium storage device.

[0032] Preferably, the air drying method further includes:

[0033] When compressed air is used for energy storage, the air is processed by the air compression and cooling devices connected in sequence before entering the adsorption air drying device for drying. After being processed by the air compression and cooling devices connected in sequence, it enters the air storage device for storage.

[0034] Preferably, the air drying method further includes:

[0035] When compressed air releases energy, the heat storage medium in the second heat storage medium storage device flows through the heating device and the adsorption air drying device, and the desiccant is regenerated by utilizing the residual heat of the heat storage medium; after the heat storage medium flows into the heat dissipation device through the second medium pipeline to release the stored compressed heat, it enters the first heat storage medium storage device.

[0036] The air drying method for compressed air energy storage described in this invention utilizes an adsorption-type air drying device to dry the air during the compressed air energy storage process. When the compressed air releases energy, the residual heat of the medium is discharged using the exhaust or heating device of the air turbine to regenerate the desiccant. By rationally allocating the adsorption and regeneration time periods of the desiccant, the circulation of the desiccant can be ensured to be consistent with the circulation of the compressed air energy storage system.

[0037] Preferably, the pressure dew point of the adsorption air drying device is -70 to -30°C, for example, it can be -70°C, -60°C, -50°C, -40°C or -30°C, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0038] The pressure dew point of the adsorption-type air drying device of the present invention is preferably -70 to -30°C, which ensures the safe operation of the compressed air energy storage system and is beneficial to the corrosion prevention of equipment and pipeline valves in the entire device system.

[0039] Preferably, the temperature for generating waste heat to regenerate the desiccant is 60–85°C, for example, 60°C, 65°C, 70°C, 75°C, 80°C, or 85°C, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0040] The preferred temperature for achieving desiccant regeneration in this invention is 60–85°C. If the temperature is too high, it will cause changes in the pore structure of the desiccant, significantly reducing its adsorption effect and affecting its usability; if the temperature is too low, the moisture adsorbed by the desiccant cannot be removed well, resulting in poor desiccant regeneration effect.

[0041] As a preferred embodiment of the present invention, the air drying method includes:

[0042] When compressed air is used for energy storage, the air enters an adsorption-type air dryer with a pressure dew point of -70 to -30°C through the air intake pipe to be dried. After being dried, the air then passes through an air compressor and a cooling unit in sequence before entering the air storage unit for storage. Alternatively, the air is processed by the preceding set of sequentially connected air compressors and cooling units before entering an adsorption-type air dryer with a pressure dew point of -70 to -30°C for drying. After being processed by the following set of sequentially connected air compressors and cooling units, the air then enters the air storage unit for storage.

[0043] The heat generated during air compression is stored by the heat storage medium, which flows from the first heat storage medium storage device through the cooling device into the second heat storage medium storage device, storing the heat of compression during air compression.

[0044] When compressed air releases energy, the compressed air in the air storage device is heated by the heating device and then enters the air turbine to do work and generate electricity. The exhaust gas from the air turbine enters the adsorption air drying device, and the waste heat of the exhaust gas temperature of 60-85℃ is used to regenerate the desiccant.

[0045] The heat storage medium in the second heat storage medium storage device flows through the heating device and the heat dissipation device, and after releasing the stored compressed heat, it enters the first heat storage medium storage device; or the heat storage medium in the second heat storage medium storage device flows through the heating device and the adsorption-type air drying device, and uses the residual heat of the heat storage medium at a temperature of 60-85°C to regenerate the desiccant; the heat storage medium flows through the second medium pipeline into the heat dissipation device to release the stored compressed heat, and then enters the first heat storage medium storage device.

[0046] Compared with the prior art, the present invention has at least the following beneficial effects:

[0047] (1) The air drying device system for compressed air energy storage provided by the present invention adsorbs moisture in the air when storing compressed air energy, and uses waste heat to regenerate the desiccant when releasing compressed air energy.

[0048] (2) The air drying device system for compressed air energy storage provided by the present invention makes reasonable use of the exhaust gas of the air turbine and the waste heat of the heat storage medium, reduces the power consumption of the heat dissipation device, and improves the energy utilization rate. Attached Figure Description

[0049] Figure 1 This is a schematic diagram of the air drying device system for compressed air energy storage provided in Example 1.

[0050] Figure 2 This is a schematic diagram of the air drying device system for compressed air energy storage provided in Example 2.

[0051] In the figure: 1-First air compression device; 2-First cooling device; 3-Second air compression device; 4-Second cooling device; 5-Air storage device; 6-First heating device; 7-First air turbine; 8-Second heating device; 9-Second air turbine; 10-First heat storage medium storage device; 11-Second heat storage medium storage device; 12-Heat dissipation device; 13-Adsorption type air drying device. Detailed Implementation

[0052] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0053] The present invention will now be described in further detail. However, the examples described below are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims.

[0054] It should be understood that in the description of this invention, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0055] It should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0056] Those skilled in the art should understand that the present invention necessarily includes the necessary pipelines, conventional valves and general pump equipment for achieving complete process, but the above content is not the main inventive point of the present invention. Those skilled in the art can add layouts based on process flow and equipment structure selection, and the present invention does not make any special requirements or specific limitations in this regard.

[0057] Example 1

[0058] This embodiment provides an air drying device system for compressed air energy storage, the structural schematic diagram of which is shown below. Figure 1 As shown.

[0059] The air drying device system has two air compressors, including a first air compressor 1 and a second air compressor 3.

[0060] The number of cooling devices is the same as the number of air compression devices, including a first cooling device 2 and a second cooling device 4.

[0061] The number of heating devices is the same as the number of air turbines, including a first heating device 6 and a second heating device 8.

[0062] The number of air turbines is the same as the number of air compression devices, and there are two air turbines, including a first air turbine 7 and a second air turbine 9.

[0063] The air drying device system includes a first air compressor 1, a first cooling device 2, a second air compressor 3, a second cooling device 4, an air storage device 5, a first heating device 6, a first air turbine 7, a second heating device 8, and a second air turbine 9 connected in sequence.

[0064] The air drying device system also includes an adsorption-type air drying device 13 and a heat dissipation device 12; the adsorption-type air drying device 13 includes an air intake pipe for the air to be dried, an exhaust pipe for the dried air, a first medium pipe, and a second medium pipe.

[0065] The adsorption-type air drying device 13 is connected to the first air compression device 1 via a dry air exhaust pipe and to the second air turbine 9 via a first medium pipe.

[0066] The air drying device system also includes a first heat storage medium storage device 10 and a second heat storage medium storage device 11;

[0067] The first heat storage medium storage device 10 is sequentially connected to the second cooling device 4, the first cooling device 2, and the second heat storage medium storage device 11.

[0068] The second heat storage medium storage device 11 is sequentially connected to the second heating device 8, the first heating device 6, the heat dissipation device 12, and the first heat storage medium storage device 10.

[0069] This embodiment also provides an air drying method for compressed air energy storage, wherein the air drying method employs the aforementioned air drying device system for compressed air energy storage; the air drying method includes:

[0070] When compressed air is stored, the air enters the adsorption-type air drying device 13 with a pressure dew point of -40℃ through the air intake pipe to be dried. After being dried, the air passes through the first air compression device 1, the first cooling device 2, the second air compression device 3, and the second cooling device 4 in sequence, and then enters the air storage device 5 for storage.

[0071] The heat generated during air compression is stored by the heat storage medium flowing from the first heat storage medium storage device 10 through the second cooling device 4 and the first cooling device 8 into the second heat storage medium storage device 11, storing the heat of compression during air compression.

[0072] When compressed air releases energy, the compressed air in the air storage device 5 passes through the first heating device 6, the first air turbine 7, the second heating device 8, and the second air turbine 9 in sequence to generate electricity. The exhaust gas from the second air turbine 9 enters the adsorption air drying device 13, and the desiccant is regenerated by utilizing the residual heat of the exhaust gas temperature of 70°C.

[0073] The heat storage medium in the second heat storage medium storage device 11 flows through the second heating device 8, the first heating device 6 and the heat dissipation device 12, and after releasing the stored compressed heat, it enters the first heat storage medium storage device 10.

[0074] Example 2

[0075] This embodiment provides an air drying device system for compressed air energy storage, the structural schematic diagram of which is shown below. Figure 2 As shown.

[0076] The air drying device system has two air compressors, including a first air compressor 1 and a second air compressor 3.

[0077] The number of cooling devices is the same as the number of air compression devices, including a first cooling device 2 and a second cooling device 4.

[0078] The number of heating devices is the same as the number of air turbines, including a first heating device 6 and a second heating device 8.

[0079] The number of air turbines is the same as the number of air compression devices, and there are two air turbines, including a first air turbine 7 and a second air turbine 9.

[0080] The air drying device system includes a first air compressor 1, a first cooling device 2, an adsorption air dryer 13, a second air compressor 3, a second cooling device 4, an air storage device 5, a first heating device 6, a first air turbine 7, a second heating device 8, and a second air turbine 9 connected in sequence.

[0081] The adsorption-type air drying device 13 includes an air intake pipe for the air to be dried, an exhaust pipe for the dried air, a first medium pipe, and a second medium pipe.

[0082] The air drying device system also includes a heat dissipation device 12.

[0083] The air drying device system also includes a first heat storage medium storage device 10 and a second heat storage medium storage device 11;

[0084] The first heat storage medium storage device 10 is sequentially connected to the second cooling device 4, the first cooling device 2, and the second heat storage medium storage device 11.

[0085] The second heat storage medium storage device 11 is sequentially connected to the second heating device 8, the first heating device 6, the adsorption air drying device 13, the heat dissipation device 12, and the first heat storage medium storage device 10.

[0086] This embodiment also provides an air drying method for compressed air energy storage, wherein the air drying method employs the aforementioned air drying device system for compressed air energy storage; the air drying method includes:

[0087] When compressed air is used for energy storage, the air passes through the first air compression device 1 and the first cooling device 2 and then enters the adsorption-type air drying device 13 with a pressure dew point of -40℃ to be dried. After passing through the second air compression device 3 and the second cooling device 4 in sequence, it enters the air storage device 5 for storage.

[0088] The heat generated during air compression is stored by the heat storage medium flowing from the first heat storage medium storage device 10 through the second cooling device 4 and the first cooling device 8 into the second heat storage medium storage device 11, storing the heat of compression during air compression.

[0089] When compressed air releases energy, the compressed air in the air storage device 5 passes through the first heating device 6, the first air turbine 7, the second heating device 8, and the second air turbine 9 in sequence to generate electricity.

[0090] The heat storage medium in the second heat storage medium storage device flows through the second heating device 8, the first heating device 6 and the adsorption air drying device 13, and uses the residual heat of the heat storage medium at a temperature of 80°C to regenerate the desiccant; the heat storage medium flows into the heat dissipation device 12 through the second medium pipeline to release the stored compression heat, and then enters the first heat storage medium storage device 10.

[0091] In summary, the air drying device system for compressed air energy storage provided by the present invention adsorbs moisture in the air during compressed air energy storage and utilizes waste heat to regenerate the desiccant during compressed air energy release. The air drying device system makes reasonable use of the exhaust gas from the air turbine and the waste heat of the heat storage medium, reduces the power consumption of the heat dissipation device, and improves the energy utilization rate.

[0092] The applicant declares that the detailed structural features of the present invention are illustrated through the above embodiments, but the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must rely on the above detailed structural features to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions for the components selected in the present invention, additions of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0093] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

Claims

1. An air drying method for compressed air energy storage, characterized in that, The air drying method employs the following air drying device system for compressed air energy storage: The air drying device system includes an air compressor, a cooling device, an air storage device, a heating device, and an air turbine connected in sequence. The air drying device system also includes an adsorption-type air drying device and a heat dissipation device; the adsorption-type air drying device includes an air intake pipe for the air to be dried, an exhaust pipe for the dried air, a first medium pipe, and a second medium pipe. The adsorption-type air drying device is connected to the heating device via a first medium pipe and to the heat dissipation device via a second medium pipe. An air handling unit is formed by sequentially connecting an air compressor and a cooling unit. The adsorption-type air drying unit is also arranged between the previous group of air handling units and the next group of air handling units along the air flow direction. The air drying method further includes: When compressed air is used for energy storage, the air is processed by the air compression and cooling devices connected in sequence before entering the adsorption air drying device for drying. After being processed by the air compression and cooling devices connected in sequence, it enters the air storage device for storage. When compressed air releases energy, the heat storage medium in the second heat storage medium storage device flows through the heating device and the adsorption air drying device, and the desiccant is regenerated by utilizing the residual heat of the heat storage medium; after the heat storage medium flows into the heat dissipation device through the second medium pipeline to release the stored compressed heat, it enters the first heat storage medium storage device. The pressure dew point of the adsorption-type air dryer is -70~-30℃.

2. The air drying method according to claim 1, characterized in that, The number of air compression devices is two or more.

3. The air drying method according to claim 1, characterized in that, The number of cooling devices is the same as the number of air compression devices.

4. The air drying method according to claim 1, characterized in that, The number of heating devices is the same as the number of air turbines.

5. The air drying method according to claim 1, characterized in that, The number of air turbines is two or more.

6. The air drying method according to claim 1, characterized in that, The number of air turbines is the same as the number of air compressors.

7. The air drying method according to claim 1, characterized in that, The air drying device system also includes a first heat storage medium storage device and a second heat storage medium storage device.

8. The air drying method according to claim 7, characterized in that, The first thermal storage medium storage device is connected in sequence to the cooling device and the second thermal storage medium storage device.

9. The air drying method according to claim 7, characterized in that, The second heat storage medium storage device is connected in sequence with the heating device, the heat dissipation device and the first heat storage medium storage device.

10. The air drying method according to claim 1, characterized in that, The temperature at which the waste heat is used to regenerate the desiccant is 60~85℃.

Images