Systems and methods for water-sealed compressed air energy storage under conditions of salt cavern roof failure

Abstract

This invention proposes a system and method for water-sealed compressed air energy storage in the event of a broken salt cavern roof. The system includes: a water storage chamber, which is a perforated salt cavern; and a gas storage chamber, which is a non-perforated salt cavern. The lower ends of the gas storage chamber and the water storage chamber are connected. An air injection / exhaust pipe, connected to the ground, is installed at the upper part of the gas storage chamber, and an air compressor is connected to the air injection / exhaust pipe. An air injection / drainage pipe, also connected to the ground, is installed at the upper end of the water storage chamber, and a power generation system is installed at the upper end of the air injection / drainage pipe. The air compressor injects compressed air into the gas storage chamber through the air injection / exhaust pipe, causing water in the water storage chamber to be discharged through the air injection / drainage pipe to drive the power generation system. This system utilizes water-sealed compressed air technology to regulate the pressure in the gas storage chamber using the water pressure in the water storage chamber, achieving efficient energy storage and release.

Description

Technical Field

[0001] This invention relates to a system and method for water-sealed compressed air energy storage in the event of damage to the top plate of a salt cavern, and belongs to the field of compressed air energy storage. Background Technology

[0002] With the continuous growth of global energy demand and the rapid development of renewable energy, efficient energy storage and dispatch have become significant challenges for power systems. While renewable energy sources such as wind and solar power offer advantages such as cleanliness and renewability, their intermittency and instability necessitate reliable energy storage technologies to balance supply and demand fluctuations and ensure the stable operation of the power system. Compressed air energy storage, as a large-scale energy storage technology, works by using an electrically driven compressor to compress air and store it in specific geological conditions such as underground salt caverns, abandoned mines, or aquifers. During peak electricity demand periods, the compressed air is released, expanded by an expander, and used to drive a generator to produce electricity.

[0003] Salt layers possess natural high sealing properties and structural stability, effectively preventing gas leakage and making them an ideal gas storage medium. Salt cavern compressed air energy storage, after years of practice and research, has achieved a high level of technological maturity and feasibility, becoming an important form of compressed air energy storage systems. Typical examples include the Huntorf power plant in Germany and the McIntosh power plant in the United States. The former, the world's first commercial compressed air energy storage power plant, was built in 1978 with a capacity of 290MW. This power plant utilizes underground salt caverns to store compressed air and employs gas heating to improve the temperature and efficiency of the expanded air. The latter, built in 1991 with a capacity of 110MW, is the world's second commercial compressed air energy storage power plant. This power plant employs advanced adiabatic compression technology, significantly improving the overall system efficiency through heat recovery.

[0004] Existing compressed gas storage (CGS) technology for salt caverns relies on a complete salt cavern structure, requiring both the top and bottom of the cavern to be salt layers. Crucially, the top of the cavern must not dissolve into the caprock to ensure the airtightness and stability of the storage chamber. However, in areas rich in salt cavern resources but with complex geological conditions, the top of the cavern may be dissolved through due to long-term dissolution within the cavern. Furthermore, the caprock being mudstone rather than salt rock is also a common problem. Current technologies cannot provide effective solutions to these situations, leading to a waste of underground space resources, increased exploration and development costs for new salt caverns, and impacting the economic benefits of the project. Summary of the Invention

[0005] To address the aforementioned technical problems in existing technologies, this invention proposes a system for water-sealed compressed air energy storage in the event of damage to the roof of a salt cavern, enabling the effective reuse of abandoned salt caverns, further optimizing energy storage efficiency and system economy, and expanding the application scope of compressed air energy storage technology under complex geological conditions.

[0006] This invention proposes a system for water-sealed compressed gas energy storage in the event of salt cavern roof failure, comprising:

[0007] A water storage cavity, wherein the water storage cavity is a dissolved salt cavern;

[0008] A gas storage chamber, which is an un-dissolved salt cavern, and the lower ends of the gas storage chamber and the water storage chamber are connected;

[0009] The upper part of the gas storage chamber is provided with an air injection and exhaust pipe connected to the ground, and an air compressor is connected to the air injection and exhaust pipe. The upper end of the water storage chamber is provided with an air injection and drainage pipe connected to the ground, and a power generation system is provided at the upper end of the air injection and drainage pipe.

[0010] The air compressor injects compressed air into the air storage chamber through the air intake and exhaust pipes, and discharges water from the water storage chamber through the water intake and exhaust pipes to drive the power generation system to generate electricity.

[0011] A further improvement of the present invention is that the power generation system includes a water turbine located at the outlet of the injection and drainage pipe, the water turbine being connected to a generator, and the water discharged through the injection and drainage pipe driving the water turbine to rotate, thereby driving the generator to generate electricity.

[0012] A further improvement of the present invention is that a water storage device is provided at the upper end of the injection and drainage pipe, and the water discharged from the salt cavern is stored in the water storage device.

[0013] A further improvement of the present invention is that the outlet of the injection and drainage pipe is provided with a main pipeline and a branch pipeline connected in parallel, the main pipeline being connected to the power generation system and the branch pipeline being connected to the water storage device.

[0014] A further improvement of the present invention is that a water pump is installed on the branch pipeline.

[0015] A further improvement of the present invention is that the system further includes a monitoring system, which includes a control system and a monitoring device, the monitoring device including a pressure sensor and a flow meter.

[0016] A further improvement of the present invention is that the air injection pipe and the water injection pipe are equipped with valves controlled by the control system.

[0017] According to another aspect of the invention, an energy storage method is also proposed, which provides a system for water-sealed compressed gas energy storage in the event of damage to the top plate of the salt cavern.

[0018] A further improvement of the present invention is that the method includes: modifying the salt cavern cavity with a damaged top plate, modifying the top plate of the salt cavern according to the location of the dissolution, and using it as a water storage cavity; and using the salt cavern cavity with an intact top plate and bottom plate that has not been dissoluted as a gas storage cavity.

[0019] A further improvement of the present invention is that the method includes:

[0020] During the energy storage phase, a high-pressure gas is injected into the gas storage chamber using an air compressor, while water is injected into the water storage chamber at the same time.

[0021] During the power generation phase, high-pressure gas is discharged through the air injection and exhaust pipes, while water is discharged through the water injection and drainage pipes, and the discharged water flow is used to generate electricity.

[0022] Compared with the prior art, the advantages of the present invention are as follows:

[0023] The system for water-sealed compressed gas energy storage in the event of salt cavern top plate failure according to the present invention utilizes the dual-cavity structure of the salt cavern. The dissolved salt cavern is used for water storage, while the undissolved salt cavern is used for gas storage. The system of the present invention achieves efficient energy storage and release by using water-sealed compressed gas technology to regulate the pressure in the gas storage cavity using the water pressure in the water storage cavity.

[0024] The water-sealed compressed air energy storage system according to the present invention, operating under conditions of salt cavern roof failure, achieves efficient resource reuse and avoids resource waste. Furthermore, the present invention also enables efficient energy storage; by combining compressed air energy storage and water-sealing technology, the overall efficiency of the energy storage system is improved.

[0025] The water-sealed compressed air energy storage system according to the present invention, operating under conditions of salt cavern roof failure, reduces system operating costs through efficient energy conversion and utilization. Utilizing natural salt caverns and water resources minimizes environmental damage and resource waste. The water turbine's high energy conversion capability ensures the system's power generation efficiency and stability. Attached Figure Description

[0026] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, in which:

[0027] Figure 1 The diagram shown is a structural schematic of a water-sealed compressed gas energy storage system in the event of damage to the top plate of a salt cavern, according to an embodiment of the present invention.

[0028] Figure 2 The diagram shown illustrates the relationship between different wellhead pressures and power generation in an energy storage method according to an embodiment of the present invention.

[0029] The accompanying drawings are not necessarily drawn to scale.

[0030] The meanings of the reference numerals in the attached figures are as follows:

[0031] 1. Air storage chamber; 2. Water storage chamber; 3. Air inlet and outlet pipes; 4. Water inlet and outlet pipes; 5. Air compressor; 6. Water turbine; 7. Generator; 8. Water pump; 9. Water storage device; 10. Power system. Detailed Implementation

[0032] To make the technical solutions and advantages of the present invention clearer, exemplary embodiments of the present invention will be described in further detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not an exhaustive list of all embodiments. Furthermore, without conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0033] With the continuous growth of global energy demand and the rapid development of renewable energy, efficient energy storage and dispatch have become significant challenges for power systems. While renewable energy sources such as wind and solar power offer advantages such as cleanliness and renewability, their intermittency and instability necessitate reliable energy storage technologies to balance supply and demand fluctuations and ensure the stable operation of the power system. Compressed air energy storage, as a large-scale energy storage technology, works by using an electrically driven compressor to compress air and store it in specific geological conditions such as underground salt caverns, abandoned mines, or aquifers. During peak electricity demand periods, the compressed air is released, expanded by an expander, and used to drive a generator to produce electricity.

[0034] Salt layers possess natural high sealing properties and structural stability, effectively preventing gas leakage and making them an ideal gas storage medium. Salt cavern compressed air energy storage, after years of practice and research, has achieved a high level of technological maturity and feasibility, becoming an important form of compressed air energy storage systems. Typical examples include the Huntorf power plant in Germany and the McIntosh power plant in the United States. The former, the world's first commercial compressed air energy storage power plant, was built in 1978 with a capacity of 290MW. This power plant utilizes underground salt caverns to store compressed air and employs gas heating to improve the temperature and efficiency of the expanded air. The latter, built in 1991 with a capacity of 110MW, is the world's second commercial compressed air energy storage power plant. This power plant employs advanced adiabatic compression technology, significantly improving the overall system efficiency through heat recovery.

[0035] Existing compressed gas storage (CGS) technology for salt caverns relies on a complete salt cavern structure, requiring both the top and bottom of the cavern to be salt layers. Crucially, the top of the cavern must not dissolve into the caprock to ensure the airtightness and stability of the storage chamber. However, in areas rich in salt cavern resources but with complex geological conditions, the top of the cavern may be dissolved through due to long-term dissolution within the cavern. Furthermore, the caprock being mudstone rather than salt rock is also a common problem. Current technologies cannot provide effective solutions to these situations, leading to a waste of underground space resources, increased exploration and development costs for new salt caverns, and impacting the economic benefits of the project.

[0036] To address the aforementioned issues, this invention proposes a system for water-sealed compressed air energy storage in the event of roof damage in salt caverns. This system enables the effective reuse of abandoned salt caverns, further optimizes energy storage efficiency and system economy, and expands the application scope of compressed air energy storage technology under complex geological conditions.

[0037] In such Figure 1 In the illustrated embodiment, a system and method for water-sealed compressed gas energy storage in the event of salt cavern roof failure includes:

[0038] Water storage cavity 2, which is a salt cavern cavity that has been dissolved and penetrated. The top plate of the salt cavern is modified according to the location of the dissolution and penetration so that it can store water, and reinforcement is carried out if necessary.

[0039] The gas storage chamber 1 is a salt cavern with an intact top plate and bottom that has not been dissolved through. To ensure the airtightness of the gas storage chamber 1, its airtightness needs to be verified through an air injection test.

[0040] The bottoms of water storage chamber 2 and air storage chamber 1 are connected.

[0041] In the system according to this embodiment, an air injection / exhaust pipe 3 connected to the ground is provided at the upper part of the air storage chamber 1, and an air injection / drainage pipe 4 connected to the ground is provided at the upper part of the water storage chamber 2.

[0042] The air compressor 5 is installed at the ground inlet of the air injection / exhaust pipe 3, and the air compressor 5 injects compressed air into the air storage chamber 1 through the air injection / exhaust pipe 3. A power generation facility is installed at the upper end of the air injection / exhaust pipe 4.

[0043] In one embodiment, the power generation facility includes a water turbine 6 located at the outlet of the water inlet / outlet pipe 4, the water turbine 6 being connected to a generator 7 and driven to rotate by the water discharged from the water inlet / outlet pipe 4, thereby driving the generator 7 to generate electricity.

[0044] After generating electricity, generator 7 transmits the electricity to power system 10.

[0045] In one embodiment, the upper end of the injection and drainage pipe 4 is also provided with a water storage device 9, in which the water discharged from the salt cavern can be stored.

[0046] In the system according to this embodiment, a water storage device 9 is located at the outlet of the water turbine 6. Water discharged from the salt cavern passes through the water turbine 6 and is stored in the water storage device 9. The water in the water storage device 9 can flow back into the water storage chamber 2 for the next cycle.

[0047] In one embodiment, the outlet of the water injection / drainage pipe 4 is provided with a main pipeline and a branch pipeline connected in parallel. The main pipeline is connected to the power generation system, and the branch pipeline is connected to the water storage device 9.

[0048] When using the system according to this embodiment, compressed air is injected into the air intake and exhaust pipe 3 by the air compressor 5. The compressed air enters the air storage chamber 1 through the air intake and exhaust pipe 3. Due to the compressibility of air, high-pressure air is formed in the air storage chamber 1. At the same time, the water in the water storage device 9 flows back into the water storage chamber 2.

[0049] When energy needs to be released, the injection and drainage pipe 4 is opened. Water in the water storage chamber 2 is discharged through the injection and drainage pipe 4 under the drive of compressed air in the air storage chamber 1. The water discharged through the injection and drainage pipe 4 passes through the water turbine 6, causing the water turbine 6 to rotate, thereby driving the generator 7 to generate electricity. After generating electricity, the generator 7 transmits the electricity to the power system 10. The water that has passed through the water turbine 6 can be stored in the water storage device 9. At the same time, the air injection and exhaust pipe 3 is opened, and the gas in the air storage chamber 1 is discharged, preparing for the next cycle.

[0050] In one embodiment, a water pump 8 is installed on the branch pipeline to inject or discharge water in the water storage chamber 2 during energy storage and release processes, thereby regulating the system pressure.

[0051] In one embodiment, the system for water-sealed compressed air energy storage in the event of damage to the top plate of the salt cavern further includes a monitoring system. The monitoring system includes a control system and a monitoring device. The monitoring device includes a pressure sensor and a flow meter. The pressure sensor can be installed in the water storage chamber 2 or the gas storage chamber 1, or it can be installed on the air injection / exhaust pipe 3 and the water injection / drainage pipe 4. There can be one or more pressure sensors installed in different locations.

[0052] The flow meter is installed on the air injection / exhaust pipe 3 and the water injection / drainage pipe 4 to measure the flow rate of injected and discharged air and water.

[0053] The air injection / venting pipe 3 and the water injection / drainage pipe 4 are equipped with valves controlled by the control system. The valves can open or close the pipes and can also adjust the opening degree to regulate the flow rate.

[0054] The control system controls the valve status based on data such as pressure and flow monitored by the monitoring device, thereby controlling the normal operation of the entire system.

[0055] In the water-sealed compressed gas energy storage system described in this embodiment, under the condition of salt cavern roof failure, the monitoring system can monitor and control the entire system's operation process, ensuring the smooth progress of the energy storage and power generation processes.

[0056] According to another aspect of the present invention, an energy storage method is proposed, which utilizes the water-sealed compressed gas energy storage system described in the above embodiments for energy storage in the event of salt cavern roof failure.

[0057] The method includes establishing a system for water-sealed compressed gas energy storage in the event of damage to the top plate of a salt cavern: modifying the salt cavern cavity with damaged top plate, modifying the top plate of the salt cavern according to the location of the dissolution, and using it as a water storage cavity 2; using the intact and undissolved salt cavern cavity at the top and bottom as a gas storage cavity 1.

[0058] The method includes:

[0059] During the energy storage phase, high-pressure gas is injected into the air storage chamber 1 using an air compressor 5, while water is injected into the water storage chamber 2 at the same time.

[0060] During the power generation stage, high-pressure gas is discharged through the air injection and exhaust pipe 3, and water is discharged through the water injection and drainage pipe 4. The discharged water flow is then used to generate electricity.

[0061] The system for water-sealed compressed gas energy storage under conditions of salt cavern top plate damage, as described in this embodiment, utilizes the dual-cavity structure of the salt cavern. The dissolved salt cavern is used for water storage, while the undissolved salt cavern is used for gas storage. The system of this invention uses water-sealed compressed gas technology to regulate the pressure in the gas storage cavity 1 using the water pressure in the water storage cavity 2, achieving efficient energy storage and release.

[0062] The water-sealed compressed air energy storage system described in this embodiment, operating under conditions of salt cavern roof failure, achieves efficient resource reuse and avoids resource waste. Furthermore, this invention enables high-efficiency energy storage; by combining compressed air energy storage and water-sealing technology, the overall efficiency of the energy storage system is improved.

[0063] The water-sealed compressed air energy storage system described in this embodiment, operating under conditions of salt cavern roof failure, reduces system operating costs through efficient energy conversion and utilization. Utilizing natural salt caverns and water resources minimizes environmental damage and resource waste. The water turbine 6 possesses highly efficient energy conversion capabilities, ensuring the system's power generation efficiency and stability.

[0064] The following description is based on a specific embodiment.

[0065] Example 1

[0066] When the top of a salt cavern is breached, a water-sealed compressed air energy storage system is established to store excess energy from unstable sources such as solar and wind power, and then use the stored energy to generate electricity.

[0067] First, site selection and evaluation are conducted: through detailed geological exploration, salt cavern modeling, environmental impact assessment, economic feasibility analysis, hydrogeological assessment, and safety assessment, the feasibility and safety of salt caverns as gas and water storage chambers are determined to ensure the successful implementation and long-term operation of the project.

[0068] System design and equipment selection.

[0069] In this embodiment, a suitable compressor model is selected to ensure that it can compress air to the target pressure range, and it is installed in the ground equipment area. In this embodiment, the compressor model is Atlas Copco ZR160VSD+, with the following technical parameters: Pressure range: maximum 10 bar (1 MPa), Flow rate range: 30-160 l / s (10⁸-576 m³ / s). 3 / h), Power: 75-160kW, Variable Speed ​​Drive: Yes (VSD+ technology), Cooling Method: Air cooling or water cooling, Noise Level: 63-69dB(A)

[0070] A high-efficiency water pump was selected to ensure that it could pump water from the storage tank into the dissolved salt cavern. In this embodiment, a Grundfos CR 90-9 pump with a maximum flow rate of 18 m³ / h was used. 3 / h, maximum head 90m, material: Grundfos CR series water pumps can be customized with duplex stainless steel and special seals, resistant to brine corrosion.

[0071] A high-efficiency turbine is selected and installed in the wellhead piping system to ensure efficient conversion of water potential energy into electrical energy. The model used in this embodiment is the GE Pelton Turbine 8000 (GE Renewable Energy–PeltonWheel), characterized by high head and high efficiency, suitable for head drops of over 250 meters and medium flow rates. It achieves high conversion efficiency, typically between 80% and 90%. Regarding materials, key components (impeller, guide vanes, bushings, etc.) are made of highly corrosion-resistant materials, such as duplex stainless steel (e.g., 2205 or 2507) or super austenitic stainless steel (e.g., 904L), suitable for resistance to brine corrosion.

[0072] Modify the gas storage chamber and water storage chamber to ensure the airtightness of the gas storage chamber, and verify its airtightness through gas injection test; modify the top plate of the salt cavern according to the location of the melt-through to enable it to store water, and reinforce it if necessary.

[0073] Pipeline system construction: Connecting surface equipment to underground salt caverns to ensure unimpeded transmission of gas and water. System commissioning and optimization: Conducting overall system commissioning to ensure coordinated operation of all components, and making optimizations and adjustments based on actual operating conditions.

[0074] (1) Calculation of the upper limit of the gas storage chamber pressure.

[0075] Assuming the usable salt cavern burial depth is 500m, the pressure calculation formula is: P = ρgh, where ρ is the average density of the overlying rock strata (assumed to be 2200 kg / m³). 3 ), gravitational acceleration (9.81 m / s²) 2 ), where h is the depth (500m).

[0076] The upper limit safety factor for the gas storage pressure is set at 0.8.

[0077] Pressure of overlying strata: P top =ρ×g×h=2200×9.81×500=10.8MPa

[0078] Upper limit of gas storage pressure: P gas_max =80%×P top =8.64MPa.

[0079] (2) Calculate the wellhead water pressure.

[0080] Set the pipe flow pressure loss P pipeloss 0.3 MPa;

[0081] Maximum pressure difference ΔP in the water-air chamber water_gas 2MPa;

[0082] Water column pressure calculation P water =ρ water ×g×h=1000×9.81×550≈5.4MPa

[0083] Considering pipe flow pressure loss, the wellhead outlet pressure under energy storage conditions is:

[0084] P outlet,storage =P gas_max -P water -P pipeloss =8.64 - 5.4 - 0.3 ≈ 2.94 MPa

[0085] The calculation of wellhead water pressure under the released energy state needs to consider the changes in pressure inside the gas storage chamber and the changes in water column height:

[0086] P outlet,release =(P gas -ΔP water_gas )-Pwater_release -P pipeloss =8.64 - 2 - (5.4 + 0.7) - 0

[0087] 0.3 = 0.14 MPa

[0088] (3) Calculate the power generation

[0089] Assuming that in one cycle, the compressed air energy in the entire storage chamber is completely released:

[0090] Assume the net volume of the gas storage chamber is V. gas_net 250,000m 3 The volumetric porosity of the sediment is 25%, and the total gas storage chamber volume is:

[0091] V gas_total =V gas_net / 0.25=250,000 / 0.25=1,000,000m 3

[0092] Assuming constant temperature (isothermal process), the ideal gas law is:

[0093] PV = nRT

[0094] Where: P is the gas pressure, V is the gas volume, n is the number of moles of gas, R is the gas constant (8.314 J / (mol·K)), and T is the absolute temperature of the gas.

[0095] During energy storage and release, the gas undergoes volume changes under different pressures.

[0096] Initial state (in gas storage state): P initial = 8.64 MPa, V initial =1,000,000m 3

[0097] Final state (in the state of energy release): P final = 6.64 MPa (or pressure under other exothermic conditions)

[0098] Volume calculations can be obtained using the ideal gas law:

[0099]

[0100] Taking the pressure in the energy release state as an example:

[0101] V final =V initial ×P initial / P final =1,000,000×8.64 / 6.64≈1,300,000m 3

[0102] The energy released during the energy release process is calculated using the following formula:

[0103]

[0104] The calculation can be simplified by approximating the average pressure:

[0105]

[0106] Considering the turbine efficiency η turbine The actual power generation was 92%, and the actual power generation was:

[0107] E actual =E×η turbine =462,000 × 0.92 = 391,920 MJ

[0108] Converting Joules (MJ) to kilowatt-hours (kW·h):

[0109] 1 kWh = 3.6 × 10 6 J = 3.6 MJ

[0110] E actual =391,920 / 3.6≈118,066kW·h

[0111] The relationship between different wellhead pressures and power generation is as follows: Figure 2 As shown.

[0112] It should be understood that the embodiments disclosed herein are not limited to the specific structures, processing steps, or materials disclosed herein, but should be extended to equivalent substitutions of these features as understood by those skilled in the art. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

[0113] In the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0114] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "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. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0115] Certain terms are used throughout this application to refer to specific system components. As those skilled in the art will recognize, the same components may often be referred to by different names, and therefore this application is not intended to distinguish components that differ only in name and not in function. The terms "an embodiment" or "embodiment" used in the specification mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Therefore, the phrase "an embodiment" or "embodiment" appearing throughout the specification does not necessarily refer to the same embodiment.

[0116] The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and to design various embodiments with various modifications suitable for a particular purpose.

[0117] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and / or modifications falling within the scope of the invention, and all changes and / or modifications made according to embodiments of the invention should be covered within the protection scope of the invention.

Claims

1. A system for water-sealed compressed air energy storage in the event of damage to the top plate of a salt cavern, characterized in that, include: Water storage cavity (2), wherein the water storage cavity (2) is a dissolved salt cavern cavity; The gas storage chamber (1) is an un-dissolved salt cavern, and the lower ends of the gas storage chamber (1) and the water storage chamber (2) are connected. Among them, the upper part of the gas storage chamber (1) is provided with an air injection and exhaust pipe (3) connected to the ground, and an air compressor (5) is connected to the air injection and exhaust pipe (3). The upper end of the water storage chamber (2) is provided with an air injection and drainage pipe (4) connected to the ground, and a power generation system is provided at the upper end of the air injection and drainage pipe (4). The air compressor (5) injects compressed air into the air storage chamber (1) through the air intake and exhaust pipe (3), and discharges the water in the water storage chamber (2) through the water intake and exhaust pipe (4) to drive the power generation system to generate electricity.

2. The system for water-sealed compressed gas energy storage under the condition of salt cavern roof failure as described in claim 1, characterized in that, The power generation system includes a water turbine (6) installed at the outlet of the water inlet and outlet pipe (4). The water turbine (6) is connected to a generator (7). The water discharged through the water inlet and outlet pipe (4) drives the water turbine (6) to rotate, thereby driving the generator (7) to generate electricity.

3. The system for water-sealed compressed gas energy storage under the condition of salt cavern roof failure according to claim 2, characterized in that, The upper end of the water inlet and outlet pipe (4) is provided with a water storage device (9), and the water discharged from the salt cave is stored in the water storage device (9).

4. The system for water-sealed compressed gas energy storage under the condition of salt cavern roof failure according to claim 3, characterized in that, The outlet of the water injection and drainage pipe (4) is provided with a main pipeline and a branch pipeline connected in parallel. The main pipeline is connected to the power generation system, and the branch pipeline is connected to the water storage device (9).

5. The system for water-sealed compressed gas energy storage under the condition of salt cavern roof failure according to claim 4, characterized in that, A water pump (8) is installed on the branch pipeline.

6. The system for water-sealed compressed gas energy storage in the event of damage to the salt cavern roof as described in claim 5, characterized in that, It also includes a monitoring system, which comprises a control system and a monitoring device, the monitoring device including pressure sensors and flow meters.

7. The system for water-sealed compressed gas energy storage in the event of salt cavern roof failure according to claim 6, characterized in that, Valves controlled by the control system are installed on the air injection / venting pipe (3) and the water injection / drainage pipe (4).

8. An energy storage method, characterized in that, A system for water-sealed compressed gas energy storage is proposed in the event of damage to the top plate of a salt cavern according to any one of claims 1 to 7.

9. The method according to claim 8, characterized in that, include: The salt cavern cavity with the damaged top plate was modified, and the top plate of the salt cavern was modified according to the location of the dissolution and perforation to serve as a water storage cavity (2); The intact, un-melted salt caverns at the top and bottom are used as gas storage chambers (1).

10. The method according to claim 9, characterized in that, include: During the energy storage phase, high-pressure gas is injected into the gas storage chamber (1) using an air compressor (5), while water is injected into the water storage chamber (2). During the power generation stage, high-pressure gas is discharged through the air injection and exhaust pipe (3), and water is discharged through the water injection and drainage pipe (4). The discharged water flow is then used to generate electricity.

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