Liquid air energy storage system

Abstract

The invention discloses a liquid air energy storage system, and particularly relates to the technical field of liquid air energy storage, the liquid air energy storage system comprises an integrated air compression assembly, the air inlet end of the integrated air compression assembly communicates with an air inlet pipe, and the liquid outlet end of the integrated air compression assembly communicates with a high-pressure storage tank; the two sides of the integrated air compression assembly are each provided with an integrated cover communicating with an inner cavity of the integrated air compression assembly, one integrated cover communicates with a recycling pipe, the top of the recycling pipe communicates with a nitrogen storage tank, a conveying pump at the bottom of the nitrogen storage tank communicates with a conveying pipe, and the conveying pipe communicates with the other integrated cover. The integrated air compression assembly comprises a first half shell and a second half shell which are spliced together to form a cylindrical shell, a plurality of air compression units connected end to end are arranged in the cylindrical shell, the air compression units communicate with one another through connecting pipes, and the air compression units are partially soaked in liquid nitrogen respectively. The liquid air energy storage system is few in overall components and convenient to install and arrange.

Description

Technical Field

[0001] The present invention belongs to the technical field of liquid air energy storage, and in particular relates to a liquid air energy storage system. Background Art

[0002] Liquid air energy storage is an emerging long-term energy storage technology that uses excess electricity to cool air into liquid form and then evaporates the liquid to drive turbines to generate electricity when needed. Liquid air energy storage systems can efficiently store and release energy, have a relatively low environmental impact, and do not rely on chemical batteries or fossil fuels to operate.

[0003] The existing liquid air energy storage system requires air to be compressed into liquid and multiple independent air compression devices are set up, which makes the device bulky and not conducive to installation, and is not conducive to heat preservation of low-temperature components, affecting the operation of the device. Therefore, a new type of liquid air energy storage system is needed. Summary of the invention

[0004] In order to solve the above problems, the present invention discloses a liquid air energy storage system.

[0005] To achieve the above object, the technical solution of the present invention is as follows:

[0006] A liquid air energy storage system comprises an integrated air compression component, wherein an air inlet end of the integrated air compression component is connected to an air inlet pipe, and a liquid outlet end of the integrated air compression component is connected to a high-pressure storage tank, and an integrated cover connected to its inner cavity is respectively arranged on both sides of the integrated air compression component, wherein one of the integrated covers is connected to a recovery pipe, and the top of the recovery pipe is connected to a nitrogen storage tank, and a bottom delivery pump of the nitrogen storage tank is connected to a delivery pipe, and the delivery pipe is connected to the other integrated cover; the integrated air compression component comprises: a first half shell and a second half shell spliced ​​together to form a cylindrical shell, wherein a plurality of air compression units connected end to end are arranged in the cylindrical shell, the plurality of air compression units are connected through a connecting pipe, and the plurality of air compression units are partially immersed in liquid nitrogen.

[0007] As a preferred technical solution of the present invention, each of the air compression units includes: a compressor for compressing air, a partition is fixedly mounted on both ends of the compressor, and the first half shell and the second half shell are provided with a groove for inserting the partition, the rotating shaft of the compressor is coaxially connected to the motor, a spiral tube is wound around the outside of the compressor, and the spiral tube body is arranged between the two partitions, one end of the spiral tube is connected to the inlet of the compressor, and the outlet of the compressor is connected to a discharge pipe.

[0008] As a preferred technical solution of the present invention, the outer surface of the compressor is extended with evenly distributed fins, and the fins are arranged between two partitions connected to the compressor, the annular space between the two partitions in the same air compression unit and outside the compressor is filled with liquid nitrogen, and the first half shell and the second half shell are both provided with through holes leading from the annular space to the integrated cover.

[0009] As a preferred technical solution of the present invention, a plurality of sealing protrusions adapted to a plurality of annular spaces are arranged at the opening of the first half shell, and a groove adapted to the sealing protrusions is provided in the second half shell.

[0010] As a preferred technical solution of the present invention, the first half shell and the second half shell are both semi-cylindrical, skirts extend from the openings of the first half shell and the second half shell, and the skirts are provided with through holes for bolt fixing.

[0011] As a preferred technical solution of the present invention, the other end of the spiral tube passes through the adjacent partition, and the discharge pipe passes through the adjacent partition, the spiral tube and the discharge pipe between adjacent air compression units are connected through a connecting pipe, and the spiral tube and the discharge pipe joint near the end of the integrated air compression assembly are respectively connected to the first extension pipe and the second extension pipe, and the side walls at both ends of the first half shell are respectively threadedly connected with an internal and external threaded pipe, and the two internal and external threaded pipes are respectively threadedly connected to the adjacent first extension pipe and the second extension pipe.

[0012] As a preferred technical solution of the present invention, the spiral tube and the discharge pipe joint arranged at the end of the first half shell are both sleeved with hexagonal sleeves, and two sockets respectively adapted for sliding insertion of the two hexagonal sleeves extend from the inner wall of the first half shell.

[0013] As a preferred technical solution of the present invention, each end of the internal and external threaded tube away from the first half shell is connected to a solenoid valve, one of the solenoid valves is connected to the air intake pipe, and the other solenoid valve is connected to the high-pressure storage tank.

[0014] As a preferred technical solution of the present invention, a replacement valve for replacing liquid nitrogen is installed on the top of the nitrogen storage tank.

[0015] The beneficial effects of the present invention are:

[0016] 1. The liquid air energy storage system is provided with an integrated air compression assembly, in which a plurality of air compression units are arranged for air compression, and the plurality of air compression units perform unified heat management. The integrated air compression assembly has a simple structure and is conducive to heat preservation treatment, which is convenient for the continuous operation of the system. Since the system has fewer overall components, its volume is small and it is easy to install and arrange;

[0017] 2. When the air is compressed, the motor acts as an electric motor to drive the compressor to operate and compress the air. The circulating liquid nitrogen in the system uniformly absorbs the heat released by the multi-stage compressed air. When releasing liquid air, the liquid gradually vaporizes and expands to drive the compressor to operate. The compressor drives the motor, and the motor acts as a generator. The circulating liquid nitrogen in the system releases heat to the multi-stage expanded air. Thanks to the absorption and release of heat by the entire liquid air energy storage system, the heat loss during the compression and expansion process is reduced, and the energy conversion efficiency of the energy storage system is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present invention;

[0019] Figure 2 It is a schematic diagram of the overall structure of another angle of an embodiment of the present invention;

[0020] Figure 3 A cross-sectional view of an integrated air compression assembly, a solenoid valve and an integrated cover according to an embodiment of the present invention;

[0021] Figure 4 This is a schematic diagram of the structure of the integrated air compression assembly and the solenoid valve without the first half shell and the second half shell according to an embodiment of the present invention;

[0022] Figure 5 An exploded view of an air compression unit, a connecting pipe, a first extension pipe, a connecting pipe, a holder, a hexagonal sleeve, and a solenoid valve according to an embodiment of the present invention;

[0023] Figure 6 An exploded view of an air compression unit, a second extension pipe, a connecting pipe, a holder, a hexagonal sleeve and a solenoid valve according to an embodiment of the present invention;

[0024] Figure 7 An exploded view of a first half shell and a second half shell of an embodiment of the present invention;

[0025] Figure 8 For the embodiment of the present invention Figure 7 Enlarged view of point A in the middle.

[0026] List of Figure Symbols:

[0027] 1. Integrated air compression assembly; 11. First half shell; 111. Sealing protrusion; 12. Second half shell; 13. Air compression unit; 131. Compressor; 132. Motor; 133. Baffle; 134. Spiral tube; 135. Discharge pipe; 14. Connecting pipe; 15. First extension pipe; 16. Internal and external threaded pipe; 17. Socket; 18. Hexagonal sleeve; 19. Second extension pipe;

[0028] 2. Integrated cover; 3. Delivery pipe; 4. Delivery pump; 5. Nitrogen storage tank; 6. Recovery pipe; 7. Replacement valve; 8. Solenoid valve; 9. Intake pipe; 10. High-pressure storage tank. DETAILED DESCRIPTION

[0029] The present invention will be further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0030] See also Figure 1-8 , a liquid air energy storage system, including an integrated air compression component 1. The air inlet end of the integrated air compression component 1 is connected to an air inlet pipe 9, and the liquid outlet end of the integrated air compression component 1 is connected to a high-pressure storage tank 10. The air sucked into the air inlet pipe 9 is filtered to remove solid particles, dehumidified, and carbon dioxide is removed by molecular sieve. An integrated cover 2 connected to its inner cavity is provided on both sides of the integrated air compression component 1, one of the integrated covers 2 is connected to a recovery pipe 6, and the top of the recovery pipe 6 is connected to a nitrogen storage tank 5. The bottom delivery pump 4 of the nitrogen storage tank 5 is connected to a delivery pipe 3, and the delivery pipe 3 is connected to another integrated cover 2. When the integrated air compression component 1 is running, the delivery pump 4 continues to work to deliver the liquid nitrogen in the nitrogen storage tank 5 to the integrated air compression component 1 through the delivery pipe 3, and then the liquid nitrogen in the integrated air compression component 1 is circulated back to the nitrogen storage tank 5 through the recovery pipe 6, so as to absorb or release heat inside the integrated air compression component 1. A displacement valve 7 for replacing liquid nitrogen is installed on the top of the nitrogen storage tank 5. The displacement valve 7 is used to displace the heated liquid nitrogen in the nitrogen storage tank 5 out of the nitrogen storage tank 5 and replenish the cooled liquid nitrogen so that the liquid nitrogen in the nitrogen storage tank 5 always remains in liquid state. The components in the drawings of the liquid air energy storage system are all buried underground, and all components need to be wrapped with insulation materials.

[0031] The integrated air compression assembly 1 comprises: a first half shell 11 and a second half shell 12 which are spliced ​​together to form a cylindrical shell. A plurality of air compression units 13 connected end to end are arranged in the cylindrical shell, and the plurality of air compression units 13 are connected through a connecting pipe 14, and the plurality of air compression units 13 are partially immersed in liquid nitrogen. Specifically, in the embodiment of the attached drawings, three air compression units 13 are arranged in the integrated air compression assembly 1, and the three air compression units 13 cool and compress the inhaled air in turn, and repeat three times until the main components in the air are compressed into liquid.

[0032] Each air compression unit 13 includes: a compressor 131 for compressing air. The compressor 131 adopts an impeller compressor, such as a centrifugal type, an axial flow type, etc. A partition 133 is fixedly sleeved at both ends of the compressor 131, and the first half shell 11 and the second half shell 12 are provided with a groove for inserting the partition 133. The rotating shaft of the compressor 131 is coaxially connected with a motor 132, and the motor 132 can act as a motor or a generator. A spiral tube 134 is wound around the outside of the compressor 131, and the main body of the spiral tube 134 is arranged between the two partitions 133. One end of the spiral tube 134 is connected to the inlet of the compressor 131, and the outlet of the compressor 131 is connected to a discharge pipe 135. The main body of the spiral tube 134 is immersed in liquid nitrogen, which is conducive to sufficient heat conduction.

[0033] The outer surface of the compressor 131 is extended with uniformly distributed fins, and the fins are arranged between two partitions 133 connected to the compressor 131. The fins of the compressor 131 are immersed in liquid nitrogen, which is conducive to sufficient heat conduction. The annular space between the two partitions 133 in the same air compression unit 13 and outside the compressor 131 is filled with liquid nitrogen, and the first half shell 11 and the second half shell 12 are both provided with through holes leading from the annular space to the integrated cover 2.

[0034] The opening of the first half shell 11 is provided with a plurality of sealing protrusions 111 adapted to the plurality of annular spaces, and the second half shell 12 is provided with a groove adapted to the sealing protrusions 111. The first half shell 11 and the second half shell 12 are both semi-cylindrical, and the openings of the first half shell 11 and the second half shell 12 are extended with skirts, and the skirts are provided with through holes for bolt fixing. The connecting bolts between the first half shell 11 and the second half shell 12 are not drawn in the drawings.

[0035] The other end of the spiral tube 134 passes through the adjacent partition 133, and the discharge pipe 135 passes through the adjacent partition 133. The spiral tubes 134 and the discharge pipes 135 between adjacent air compression units 13 are connected through the connecting pipe 14. The joints of the spiral tube 134 and the discharge pipe 135 near the end of the integrated air compression assembly 1 are respectively connected to the first extension pipe 15 and the second extension pipe 19. The side walls at both ends of the first half shell 11 are respectively threadedly connected with an internal and external threaded pipe 16, and the two internal and external threaded pipes 16 are respectively threadedly connected to the adjacent first extension pipe 15 and the second extension pipe 19.

[0036] The joints of the spiral tube 134 and the discharge tube 135 disposed at the end of the first half shell 11 are both sleeved with a hexagonal sleeve 18, and two clamping seats 17 are extended from the inner wall of the first half shell 11 to respectively fit the two hexagonal sleeves 18 to slide into. After the first half shell 11 and the second half shell 12 are put together, the two hexagonal sleeves 18 are respectively slidably inserted into the two clamping seats 17, so that the two internal and external threaded tubes 16 are respectively rotated and screwed into the first extension tube 15 and the second extension tube 19.

[0037] The end of each internal and external threaded tube 16 away from the first half shell 11 is connected to a solenoid valve 8, one of the solenoid valves 8 is connected to the air intake pipe 9, and the other solenoid valve 8 is connected to the high-pressure storage tank 10 for assisting in controlling air compression and release.

[0038] Working principle:

[0039] During air compression, the delivery pump 4 continuously works to deliver the liquid nitrogen in the nitrogen storage tank 5 to the integrated air compression assembly 1 through the delivery pipe 3, and then the liquid nitrogen in the integrated air compression assembly 1 is circulated back to the nitrogen storage tank 5 through the recovery pipe 6, and then the two solenoid valves 8 are opened, and the plurality of air compression units 13 are opened, and the integrated air compression assembly 1 inhales air from the air intake pipe 9, wherein the motor 132 acts as a motor to drive the compressor 131 to operate compressed air, and the air entering the compressor 131 first enters the spiral tube 134 immersed in liquid nitrogen to cool down, and is repeatedly cooled and then compressed several times, so that the main components in the air are compressed into liquid, and then the liquid is delivered to the high-pressure storage tank 10 for storage, and at the same time, the liquid nitrogen absorbs the heat released by the compressed air (through the outer shell of the compressor 131 and the extended fins) and the heat of the input air (through the spiral tube 134), and the temperature and pressure of the circulating liquid nitrogen rise;

[0040] When releasing liquid air, the delivery pump 4 continues to work to deliver the liquid nitrogen in the nitrogen storage tank 5 to the integrated air compression assembly 1 through the delivery pipe 3, and then the liquid nitrogen in the integrated air compression assembly 1 is circulated back to the nitrogen storage tank 5 through the recovery pipe 6, and then the two solenoid valves 8 are opened, and then the high-pressure liquid passes through a plurality of air compression units 13 from the high-pressure storage tank 10 in sequence, and finally the heat-absorbing and expanded air is discharged from the intake pipe 9, wherein the liquid gradually vaporizes and expands to drive the compressor 131 to operate, and the compressor 131 drives the motor 132. At this time, the motor 132 acts as a generator, and the generated gas absorbs heat from the liquid nitrogen through the spiral tube 134 and the outer shell of the compressor 131 and the extended fins, so that the circulating liquid nitrogen is cooled as a whole, and the entire liquid air energy storage reduces the heat loss during the compression and expansion process while completing the energy storage and energy release.

[0041] It should be noted that the above content only illustrates the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications all fall within the protection scope of the claims of the present invention.

Claims

1. A liquid air energy storage system, comprising an integrated air compression assembly (1), characterized in that: The air inlet end of the integrated air compression component (1) is connected to an air inlet pipe (9), and the liquid outlet end of the integrated air compression component (1) is connected to a high-pressure storage tank (10). An integrated cover (2) connected to its inner cavity is respectively arranged on both sides of the integrated air compression component (1), one of the integrated covers (2) is connected to a recovery pipe (6), and the top of the recovery pipe (6) is connected to a nitrogen storage tank (5), and the bottom delivery pump (4) of the nitrogen storage tank (5) is connected to a delivery pipe (3), and the delivery pipe (3) is connected to the other integrated cover (2); the integrated air compression component (1) comprises: a first half shell (11) and a second half shell (12) spliced ​​together to form a cylindrical shell, wherein a plurality of air compression units (13) connected end to end are arranged in the cylindrical shell, the plurality of air compression units (13) are connected to each other through a connecting pipe (14), and the plurality of air compression units (13) are respectively partially immersed in liquid nitrogen.

2. A liquid air energy storage system according to claim 1, characterized in that: Each of the air compression units (13) comprises: a compressor (131) for compressing air; a partition (133) is fixedly sleeved on both ends of the compressor (131); a first half shell (11) and a second half shell (12) are provided with a groove for inserting the partition (133); a rotating shaft of the compressor (131) is coaxially connected to a motor (132); a spiral tube (134) is wound around the outside of the compressor (131); a main body of the spiral tube (134) is arranged between two partitions (133); one end of the spiral tube (134) is connected to an inlet of the compressor (131); and an outlet of the compressor (131) is connected to a discharge pipe (135).

3. A liquid air energy storage system according to claim 2, characterized in that: The outer surface of the compressor (131) is extended with evenly distributed fins, and the fins are arranged between two partitions (133) connected to the compressor (131); the annular space between the two partitions (133) in the same air compression unit (13) and outside the compressor (131) is filled with liquid nitrogen, and the first half shell (11) and the second half shell (12) are both provided with through holes leading from the annular space to the integrated cover (2).

4. A liquid air energy storage system according to claim 3, characterized in that: A plurality of sealing protrusions (111) adapted to a plurality of annular spaces are arranged at the opening of the first half shell (11), and a groove adapted to the sealing protrusions (111) is provided on the second half shell (12).

5. A liquid air energy storage system according to claim 3, characterized in that: The first half shell (11) and the second half shell (12) are both semi-cylindrical, and skirts extend from the openings of the first half shell (11) and the second half shell (12), and the skirts are provided with through holes for bolt fixing.

6. A liquid air energy storage system according to claim 2, characterized in that: The other end of the spiral tube (134) passes through the adjacent partition (133), and the discharge pipe (135) passes through the adjacent partition (133). The spiral tubes (134) and the discharge pipes (135) between adjacent air compression units (13) are connected via a connecting pipe (14). The joints of the spiral tube (134) and the discharge pipe (135) near the end of the integrated air compression assembly (1) are respectively connected to a first extension pipe (15) and a second extension pipe (19). The side walls at both ends of the first half shell (11) are respectively threadedly connected to an internal and external threaded tube (16), and the two internal and external threaded tubes (16) are respectively threadedly connected to the adjacent first extension pipe (15) and the second extension pipe (19).

7. A liquid air energy storage system according to claim 6, characterized in that: The spiral tube (134) and the discharge tube (135) joints arranged at the ends of the first half shell (11) are both sleeved with hexagonal sleeves (18), and the inner wall of the first half shell (11) is extended with two sockets (17) respectively adapted for sliding insertion of the two hexagonal sleeves (18).

8. A liquid air energy storage system according to claim 6, characterized in that: The end of each of the internal and external threaded tubes (16) away from the first half shell (11) is connected to a solenoid valve (8), one of the solenoid valves (8) is connected to the air intake pipe (9), and the other solenoid valve (8) is connected to the high-pressure storage tank (10).

9. A liquid air energy storage system according to claim 1, characterized in that: A displacement valve (7) for displacing liquid nitrogen is installed on the top of the nitrogen storage tank (5).

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