Compressed air energy storage system and method for power plant

Abstract

The invention discloses a compressed air energy storage system and method for a power plant. An outlet of an air compressor is connected with a dryer, an outlet of the dryer is connected with air filtering equipment, and an outlet of the air filtering equipment communicates with a primary side inlet of a first air heat exchanger; a primary side outlet of the first air heat exchanger is communicated with an inlet of the gas storage pressure container, a secondary side inlet of the first air heat exchanger is communicated with the external environment, and a secondary side outlet of the first air heat exchanger is communicated with an inlet of the heat insulation storage negative pressure container. An outlet of the heat insulation storage negative pressure container is communicated with a secondary side inlet of the second air heat exchanger, an outlet of the gas storage pressure container is communicated with a primary side inlet of the second air heat exchanger, a primary side outlet of the second air heat exchanger is communicated with an inlet of the turbine, and the turbine is connected with the generator. The system and the method are low in compressed air storage cost.

Description

Technical Field

[0001] The present invention belongs to the technical field of compressed air energy storage, and relates to a compressed air energy storage system and method for a power plant. Background Art

[0002] A power plant is a power plant that converts some form of raw energy into electrical energy for fixed facilities or transportation, such as thermal, hydro, steam, diesel or nuclear power plants. The main function of compressed air energy storage technology in a power plant is to compress the air with the surplus electricity when the power grid load is low, and store it in a high-pressure sealed facility, and release it to drive the generator to generate electricity during peak hours. The stored compressed air usually needs to be heated in the combustion chamber to increase its temperature to improve the efficiency of the turbine, and then the generator converts the kinetic energy into electrical energy. However, the use of combustion chamber heating requires a large amount of fuel, which increases costs, and fuel combustion easily pollutes the environment, and the environmental protection is poor, which needs to be improved. Summary of the invention

[0003] The purpose of the present invention is to overcome the above-mentioned shortcomings of the prior art and to provide a compressed air energy storage system and method for a power plant, wherein the system and method have low cost when storing compressed air.

[0004] To achieve the above-mentioned purpose, the present invention discloses a compressed air energy storage system for a power plant, comprising an air compressor, a first air heat exchanger, a gas storage pressure vessel, an insulated storage negative pressure vessel, a second air heat exchanger, a turbine and a generator, the outlet of the air compressor is connected to a dryer, the outlet of the dryer is connected to an air filter, the outlet of the air filter is connected to the primary inlet of the first air heat exchanger, the primary outlet of the first air heat exchanger is connected to the inlet of the gas storage pressure vessel, the secondary inlet of the first air heat exchanger is connected to the external environment, the secondary outlet of the first air heat exchanger is connected to the inlet of the insulated storage negative pressure vessel, the outlet of the insulated storage negative pressure vessel is connected to the secondary inlet of the second air heat exchanger, the outlet of the gas storage pressure vessel is connected to the primary inlet of the second air heat exchanger, the primary outlet of the second air heat exchanger is connected to the inlet of the turbine, and the turbine is connected to the generator.

[0005] The further improvement of the compressed air energy storage system for power plants of the present invention is:

[0006] Furthermore, a high temperature resistant vacuum pump is installed on the pipeline between the insulated storage negative pressure container and the second air heat exchanger.

[0007] Furthermore, a gas isolation valve is provided at the primary inlet and the primary outlet of the gas storage pressure vessel.

[0008] Furthermore, a gas isolation valve is provided at the primary inlet and the primary outlet of the insulated storage negative pressure container.

[0009] Furthermore, the insulated storage negative pressure container adopts an inner and outer double-layer design.

[0010] Furthermore, the space between the outside and the inside of the insulated storage negative pressure container is evacuated into a vacuum state.

[0011] The present invention discloses a compressed air energy storage method for a power plant, comprising the following steps:

[0012] The air is compressed by an air compressor and then pressed into a dryer. The dryer is used to dry the compressed air. The compressed air is then filtered by an air filter to remove impurities in the compressed air. The compressed air and normal air are then exchanged with each other through a first air heat exchanger to reduce the temperature of the compressed air and heat the normal air at the same time. The compressed air and the heated air are then stored in a gas storage pressure vessel and an insulated storage negative pressure vessel respectively. The compressed air and the heated air are then exchanged with each other through a second air heat exchanger to increase the temperature of the compressed air. Finally, the compressed air is sent to a turbine, which drives a generator to convert kinetic energy into electrical energy.

[0013] The further improvement of the compressed air energy storage method for power plants of the present invention is:

[0014] Furthermore, gas isolation valves are provided at the primary inlet and the primary outlet of the gas storage pressure vessel and the primary inlet and the primary outlet of the insulated storage negative pressure vessel.

[0015] Furthermore, the insulated storage negative pressure container adopts an inner and outer double-layer design.

[0016] Furthermore, the space between the outside and the inside of the insulated storage negative pressure container is evacuated into a vacuum state.

[0017] The present invention has the following beneficial effects:

[0018] During specific operation of the compressed air energy storage system and method for power plants described in the present invention, when an air compressor is used to compress air, the air will generate high temperature, and heat exchange operation is performed through a first air heat exchanger, and then the low-temperature compressed air is stored in a gas storage pressure vessel, and the heat-exchanged high-temperature air is stored in an insulated storage negative pressure container. When the air is released during peak power consumption to drive the generator to generate electricity, the gas storage pressure vessel and the insulated storage negative pressure container simultaneously discharge the air into the second air heat exchanger, and heat exchange the air again to heat the compressed air and increase the temperature of the air entering the turbine to improve the efficiency of the turbine. In this process, there is no need to use fuel to heat the compressed air, which saves fuel and has good environmental protection.

[0019] Furthermore, the air compressed by the air compressor is dried and impurities in the compressed air are removed by a dryer and an air filter, so as to keep the compressed air dry and clean.

[0020] Furthermore, the insulated storage negative pressure container adopts an inner and outer double-layer design to facilitate thermal insulation and effectively prevent the transfer of heat. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0022] Figure 1 It is the principle diagram of the present invention;

[0023] Figure 2 It is a structural diagram of the present invention.

[0024] Among them, 1 is an air compressor, 2 is a dryer, 3 is an air filtering device, 4 is a first air heat exchanger, 5 is a gas storage pressure vessel, 6 is a second air heat exchanger, 7 is a turbine, 8 is a generator, and 9 is an insulated storage negative pressure container. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] In the description of the present invention, it should be understood that the terms “include” and “comprises” indicate the presence of described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or collections thereof.

[0027] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0028] It should be further understood that the term "and / or" used in the present specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes these combinations. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in the present invention generally indicates that the associated objects are in an "or" relationship.

[0029] It should be understood that, although the terms first, second, third, etc. may be used to describe preset ranges, etc. in the embodiments of the present invention, these preset ranges should not be limited to these terms. These terms are only used to distinguish preset ranges from each other. For example, without departing from the scope of the embodiments of the present invention, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0030] The word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0031] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can usually be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0032] Various structural schematic diagrams of the embodiments disclosed in the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0033] Embodiment 1

[0034] refer to Figure 1 The compressed air energy storage system for power plants described in the present invention comprises an air compression unit, a compressed air storage unit, an air energy release unit and an air energy conversion unit. The air compression unit comprises an air compressor 1 and an air processing module. The air compressor 1 is used to compress air. The air processing module is used to process compressed air. The air processing module comprises a dryer 2, an air filter 3, a first air heat exchanger 4 and an insulated storage negative pressure container 9. The compressed air storage unit is a gas storage pressure container 5. The air energy release unit comprises a heat exchange module and an energy release module. The heat exchange module is a second air heat exchanger 6. The energy release module is a turbine 7. The air energy conversion unit is a generator 8. The dryer 2 and the air filter 3 are used to The compressed air is dried and filtered to keep it dry and clean. The first air heat exchanger 4 is used for heat exchange of the compressed air and for cooling the compressed air. The gas storage pressure vessel 5 is used to store compressed air. The insulated storage negative pressure vessel 9 is used to store hot air generated after heat exchange by the first air heat exchanger 4. The second air heat exchanger 6 is used to perform heat exchange on the gas released from the gas storage pressure vessel 5 and the insulated storage negative pressure vessel 9 to heat up the compressed air and increase the temperature of the air entering the turbine 7 to improve the efficiency of the turbine 7. The turbine 7 is used to reduce the pressure and temperature of the high-pressure and high-temperature air to convert the internal energy into kinetic energy, which is then converted into electrical energy by the generator 8.

[0035] In this embodiment, the air compression unit is provided to facilitate the compression of air. At the same time, the first air heat exchanger 4 is provided to perform heat exchange operations on high-temperature compressed air and normal air, which is convenient for heat recovery and utilization to avoid heat waste. The gas storage pressure container 5 and the insulated storage negative pressure container 9 are used to store compressed air and heated air. The second air heat exchanger 6 is provided to facilitate secondary heat exchange operations on the compressed air and heated air, thereby increasing the temperature of the compressed air. The high-temperature compressed air can improve the efficiency of the turbine 7.

[0036] refer to Figure 2 Specifically, the compressed air energy storage system for a power plant described in the present invention includes an air compressor 1, a dryer 2, an air filter 3, a first air heat exchanger 4, a gas storage pressure vessel 5, a second air heat exchanger 6, a turbine 7, a generator 8 and an insulated storage negative pressure container 9. The outlet of the air compressor 1 is connected to the dryer 2 through a pipeline, and the outlet of the dryer 2 is connected to the air filter 3 through a pipeline. The outlet of the air filter 3 is connected to the primary side inlet of the first air heat exchanger 4, the primary side outlet of the first air heat exchanger 4 is connected to the inlet of the gas storage pressure vessel 5, the secondary side inlet of the first air heat exchanger 4 is connected to the external environment, the secondary side outlet of the first air heat exchanger 4 is connected to the inlet of the insulated storage negative pressure container 9, the outlet of the insulated storage negative pressure container 9 is connected to the secondary side inlet of the second air heat exchanger 6, the outlet of the gas storage pressure vessel 5 is connected to the primary side inlet of the second air heat exchanger 6, the primary side outlet of the second air heat exchanger 6 is connected to the inlet of the turbine 7, and the turbine 7 is connected to the generator 8.

[0037] A high temperature resistant vacuum pump is installed on the pipeline between the heat-insulating storage negative pressure container 9 and the second air heat exchanger 6 .

[0038] Accordingly, reference Figure 2 This embodiment also discloses a compressed air energy storage method for a power plant. Based on the compressed air energy storage system for a power plant, the compressed air energy storage method for a power plant includes the following steps:

[0039] When the load of the power grid is low, the air is compressed by the air compressor 1 and pressed into the dryer 2. The high-temperature compressed air is dried by the dryer 2, and then the compressed air is filtered by the air filter 3 to remove impurities in the compressed air, thereby maintaining the dryness and cleanliness of the compressed air. The high-temperature compressed air and normal air are then exchanged with each other through the first air heat exchanger 4 to reduce the temperature of the compressed air and heat the normal air at the same time. The compressed air and the heated air are stored in the gas storage pressure container 5 and the insulated storage negative pressure container 9 respectively, and then the compressed air and the heated air are exchanged with each other by the second air heat exchanger 6 to increase the temperature of the compressed air. The high-temperature compressed air can improve the efficiency of the turbine 7. The high-pressure and high-temperature air is then depressurized and cooled by the turbine 7 to convert the internal energy into kinetic energy, and then the kinetic energy is converted into electrical energy by the generator 8.

[0040] Embodiment 2

[0041] refer to Figure 2 In this embodiment, the air inlet and exhaust ends of the gas storage pressure container 5 and the insulated storage negative pressure container 9 are both equipped with gas isolation valves. The insulated storage negative pressure container 9 is a double-layer design with inner and outer layers, and the space between the outside and inside of the insulated storage negative pressure container 9 is in a vacuum state.

[0042] In this embodiment, a gas isolation valve is provided to protect the air inlet and exhaust ends of the gas storage pressure vessel 5 and the insulated storage negative pressure container 9. When the gas isolation valve is closed, the internal gas of the gas storage pressure vessel 5 and the insulated storage negative pressure container 9 can be prevented from leaking. The insulated storage negative pressure container 9 adopts an inner and outer double-layer design. The space between the outside and the inside of the insulated storage negative pressure container 9 is evacuated into a vacuum state. The reduction of gas molecules in the vacuum state is used to reduce heat conduction and convection, thereby achieving the purpose of insulation and effectively preventing the transfer of heat.

[0043] The air is compressed by the air compressor 1 and discharged into the dryer 2 for drying. The dried compressed air is then discharged into the air filter 3 to remove impurities in the compressed air, and then discharged into the first air heat exchanger 4. Normal air is introduced through the other air inlet end of the first air heat exchanger 4. At this time, the high-temperature air after compression and the normal air complete heat exchange in the first air heat exchanger 4, so that the compressed air is cooled and the normal air is heated. The first air heat exchanger 4 then discharges the compressed air into the gas storage pressure container 5 for storage, and at the same time, the gas isolation valve at the air inlet end of the heat-insulating storage negative pressure container 9 is opened, and the heated air is sucked into the heat-insulating storage negative pressure container 9. The high-temperature air is stored inside, and then the gas isolation valve at the air inlet end of the insulated storage negative pressure container 9 is closed after storing the high-temperature air. During the peak electricity consumption, the air is released to drive the generator 8 to generate electricity. The gas storage pressure container 5 discharges the compressed air into the second air heat exchanger 6. At the same time, the high-temperature air inside the insulated storage negative pressure container 9 is extracted by a high-temperature resistant vacuum pump, and the high-temperature air is discharged into the second air heat exchanger 6. The second air heat exchanger 6 is used to perform heat exchange operation on the air again to heat the compressed air. The high-temperature compressed air can improve the efficiency of the turbine 7. The heated compressed air is depressurized and cooled by the turbine 7, so that the internal energy is converted into kinetic energy, and then the generator 8 converts the kinetic energy into electrical energy.

[0044] The present invention has the following characteristics:

[0045] The present invention adopts the cooperation of an air compressor 1, a dryer 2, an air filtering device 3, a first air heat exchanger 4, a gas storage pressure vessel 5, a second air heat exchanger 6, a turbine 7, a generator 8 and an insulated storage negative pressure container 9. When the air compressor 1 is used to compress the air, the air will generate high temperature. The first air heat exchanger 4 performs heat exchange operation, and the low-temperature compressed air after heat exchange is stored in the gas storage pressure vessel 5, and the high-temperature air after heat exchange is stored in the insulated storage negative pressure container 9. When the air is released during the peak power consumption to drive the generator 8 to generate electricity, the gas storage pressure vessel 5 and the insulated storage negative pressure container 9 simultaneously discharge the air into the second air heat exchanger 6, and the air is heat exchanged again to heat the compressed air and increase the temperature of the air entering the turbine 7 to improve the efficiency of the turbine 7. The generator 8 is then used to convert kinetic energy into electrical energy. In this process, there is no need to use fuel to heat the compressed air, which saves fuel and has good environmental protection.

[0046] The present invention facilitates drying the air compressed by the air compressor 1 through the cooperation of the dryer 2 and the air filter device 3, and can remove impurities in the compressed air, so as to facilitate maintaining the dryness and cleanliness of the compressed air.

[0047] The heat-insulating storage negative pressure container 9 of the present invention adopts an inner and outer double-layer design, and the space between the outer and inner parts of the heat-insulating storage negative pressure container 9 is evacuated into a vacuum state, which is convenient for heat insulation and effectively prevents heat transfer.

[0048] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and disclosure of the invention. This application is intended to cover any variations, uses or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not disclosed by the present invention. The specification and examples are to be considered exemplary only, and the true scope and spirit of the present invention are indicated by the following claims.

[0049] It should be understood that the present invention is not limited to the exact construction that has been described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

[0050] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural change made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A compressed air energy storage system for a power plant, characterized in that: The invention comprises an air compressor (1, a first air heat exchanger (4), a gas storage pressure container (5), an insulated storage negative pressure container (9), a second air heat exchanger (6), a turbine (7) and a generator (8), wherein the outlet of the air compressor (1) is connected to a dryer (2), the outlet of the dryer (2) is connected to an air filter (3), the outlet of the air filter (3) is connected to the primary side inlet of the first air heat exchanger (4), and the primary side outlet of the first air heat exchanger (4) is connected to the inlet of the gas storage pressure container (5). The secondary side inlet of the first air heat exchanger (4) is connected to the external environment, the secondary side outlet of the first air heat exchanger (4) is connected to the inlet of the insulated storage negative pressure container (9), the outlet of the insulated storage negative pressure container (9) is connected to the secondary side inlet of the second air heat exchanger (6), the outlet of the gas storage pressure container (5) is connected to the primary side inlet of the second air heat exchanger (6), the primary side outlet of the second air heat exchanger (6) is connected to the inlet of the turbine (7), and the turbine (7) is connected to the generator (8).

2. The compressed air energy storage system for power plants according to claim 1, characterized in that: A high temperature resistant vacuum pump is installed on the pipeline between the heat-insulating storage negative pressure container (9) and the second air heat exchanger (6).

3. The compressed air energy storage system for power plants according to claim 1, characterized in that: Gas isolation valves are provided at the primary inlet and the primary outlet of the gas storage pressure container (5).

4. The compressed air energy storage system for power plants according to claim 1, characterized in that: Gas isolation valves are provided at the primary inlet and the primary outlet of the heat-insulating storage negative pressure container (9).

5. The compressed air energy storage system for power plants according to claim 1, characterized in that: The heat-insulating storage negative pressure container (9) adopts an inner and outer double-layer design.

6. The compressed air energy storage system for power plants according to claim 5, characterized in that: The space between the outside and the inside of the heat-insulating storage negative pressure container (9) is evacuated into a vacuum state.

7. A compressed air energy storage method for a power plant, characterized in that: The compressed air energy storage system for a power plant according to claim 1 comprises the following steps: The air is compressed by an air compressor (1) and then pressed into a dryer (2). The dryer (2) is used to dry the compressed air. The compressed air is then filtered by an air filter (3) to remove impurities in the compressed air. The compressed air and normal air are then exchanged with each other through a first air heat exchanger (4) to reduce the temperature of the compressed air and simultaneously increase the temperature of the normal air. The compressed air and the heated air are then stored in a gas storage pressure container (5) and a heat-insulated storage negative pressure container (9) respectively. The compressed air and the heated air are then exchanged with each other through a second air heat exchanger (6) to increase the temperature of the compressed air. Finally, the compressed air is sent to a turbine (7). The turbine (7) drives a generator (8) to convert kinetic energy into electrical energy.

8. The compressed air energy storage method for power plants according to claim 7, characterized in that: Gas isolation valves are provided at the primary inlet and the primary outlet of the gas storage pressure container (5) and the primary inlet and the primary outlet of the heat-insulating storage negative pressure container (9).

9. The compressed air energy storage method for power plants according to claim 7, characterized in that: The heat-insulating storage negative pressure container (9) adopts an inner and outer double-layer design.

10. The compressed air energy storage method for power plants according to claim 8, characterized in that: The space between the outside and the inside of the heat-insulating storage negative pressure container (9) is evacuated into a vacuum state.

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