Sealing and reinforcing structure of compressed air energy storage underground gas storage

Abstract

The utility model relates to the field of transformation of underground compressed air storage reservoirs, in particular to a sealing and reinforcing structure of a compressed air energy storage underground air storage reservoir. A compressed air energy storage underground gas storage sealing and reinforcing structure comprises a bearing structure, a sealing structure and a reinforcing structure, the bearing structure is provided with preset bending radian and bearing force, and corresponding bearing and limiting supporting operation can be carried out; the movable slurry bearing bag structure is movably connected with the bearing structure, has preset deformation force and bearing space, and can carry out corresponding bearing and deformation matching operation; and the prefabricated anchor rod structure has preset operation length and supporting force and is connected with the movable slurry bearing bag structure, the side wall of the prefabricated anchor rod structure is hollow, and corresponding connection and positioning operation can be carried out. Gas leakage can be reduced through the movable slurry bearing bag structure, the sealing performance of the cavern is improved, the stability of the cavern can be effectively improved through the prefabricated anchor rod structure, and the service life of the cavern is prolonged.

Description

Technical Field

[0001] The utility model relates to the field of transformation of underground compressed air storage reservoirs, and in particular to a sealing and reinforcement structure of a compressed air energy storage underground storage reservoir. Background Art

[0002] Renewable energy generation is a key component of this, but its volatility and intermittent nature make new power generation systems unstable. To mitigate this, storing energy until needed and then releasing it to the grid has gained widespread attention. Currently, my country has listed compressed air energy storage as one of its key energy storage demonstration projects. Compressed air energy storage stores electricity during periods of low electricity demand and releases it during peak periods, addressing energy waste and shortages. Currently, the most mature methods are surface gas storage and salt cavern storage. However, surface gas storage can significantly waste surface resources, while salt cavern storage is difficult to implement on a large scale due to my country's rock formation distribution. Abandoned mines are increasing in my country, and most are regular in shape and relatively stable. The large number of abandoned mines provides a good underground space for compressed air storage. Underground compressed air energy storage offers large gas storage capacities, significantly conserves surface resources, and offers a high safety factor. Therefore, most compressed air storage facilities are currently underground.

[0003] The two most critical issues in underground gas storage are sealing and stability. Existing energy storage technologies require pressures exceeding 15-20 MPa. During the repeated inflation and deflation of compressed air, the surrounding rock will crack to varying degrees, causing instability in the cavern. Existing research indicates that during the repeated inflation and deflation of compressed air energy storage caverns, relatively large cracks often develop in the surrounding rock of underground gas storage caverns. Furthermore, under the cyclical loads of repeated gas storage and deflation, the concrete lining of the compressed air energy storage cavern is prone to cracking and repeated aggregation, which can easily lead to gas leakage and damage to the entire structure. Therefore, the sealing of the lining and the reinforcement of the surrounding rock are crucial to the stable operation of the entire compressed air energy storage facility. Utility Model Content

[0004] The purpose of the utility model is to provide a sealed and reinforced structure for a compressed air energy storage underground gas storage to solve the above-mentioned problems existing in the prior art.

[0005] Technical solution: A sealed reinforcement structure for a compressed air energy storage underground gas storage reservoir, comprising three components: a supporting structure, a movable slurry bag structure, and a prefabricated anchor rod structure. The supporting structure has a predetermined bending curvature and supporting force, and can perform corresponding supporting and limiting support operations. The movable slurry bag structure is movably connected to the supporting structure, has a predetermined deformation force and bearing space, and can perform corresponding bearing and deformation coordination operations. The prefabricated anchor rod structure has a predetermined operating length and supporting force, and is connected to the movable slurry bag structure, with a hollow side wall, and can perform corresponding connection and positioning operations.

[0006] In a further embodiment, the supporting structure includes an elastic pick and a first expansion bolt; the elastic pick has a predetermined bending curvature and operating length, and can perform corresponding supporting operations; the first expansion bolt is connected to the elastic pick, and there are multiple of them, which are used for mutual communication between the elastic pick and the concrete lining.

[0007] In a further embodiment, the movable slurry bag structure includes a slurry bag, a screw and a second expansion bolt; the slurry bag has a predetermined bearing space and deformation force, is attached to the elastic pick, and can perform corresponding bearing and limiting operations; the screw is connected to the slurry bag, and extends a predetermined distance outside the slurry bag, and is multiple, and can perform corresponding connection and positioning operations; the second expansion bolt is connected to the screw, has a predetermined operating length and supporting force, and is multiple, and can perform corresponding positioning operations.

[0008] In a further embodiment, the prefabricated anchor rod structure is a prefabricated anchor rod with a hollow side wall and a predetermined working length, and a plurality of through holes are provided on the surface of the side wall; the prefabricated anchor rod is threadedly connected to the movable grout bag structure.

[0009] Beneficial effects: A sealing and reinforcement structure for a compressed air energy storage cavern can effectively solve the safety problems of some gas storage caverns and has the following beneficial effects:

[0010] (1) Improved sealing performance of compressed air underground gas storage caverns: When the underground gas storage caverns are filled with gas and pressurized, the elastic paddle support structure is squeezed by the gas pressurization, causing the slurry bag device containing the plastic fluid to deform under the action of gas squeezing and squeeze into the cracks in the segmented lining caused by the increase in inflation pressure, thereby reducing gas leakage and improving the sealing performance of the caverns.

[0011] (2) Improvement of the stability of the surrounding rock of the underground gas storage cavern: Previous studies have shown that the surrounding rock of the compressed air energy storage cavern is prone to cracks during the long-term repeated loading process of inflation and release cycles. The device is equipped with a prefabricated anchor rod with a solid center, hollow side walls and holes, and a detachable grouting bag device at the end of the anchor rod. During the repeated inflation and pressurization of the gas inside the cavern, the surrounding rock will crack under the long-term action of the cyclic pressure. At this time, the high-ductility grouting bag can be removed and replaced with grouting material to reinforce the surrounding rock. Under the pressure of inflation, the slurry enters the cracks of the surrounding rock along the side wall of the anchor rod through the holes, and can be used to reinforce the surrounding rock, improve the stability of the cavern, and extend the service life of the cavern. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of an implementation method of an underground gas storage for compressed air energy storage.

[0013] Figure 2 This is a cross-sectional view of prefabricated anchor rods for compressed air energy storage underground gas storage.

[0014] Figure 3 yes Figure 2 Enlarged schematic diagram of the connection between the prefabricated anchor rod end and the grout bag in area A.

[0015] The reference numerals in the figure are: supporting structure 1, elastic pick 11, first expansion bolt 12, movable slurry bag structure 2, slurry bag 21, screw 22, second expansion bolt 23, prefabricated anchor rod structure 3, anchor rod side wall hole 31, prefabricated solid concrete 32, anchor rod top sealing structure 33, concrete segmented lining 4, flexible waterproof board 5, surrounding rock 6. DETAILED DESCRIPTION

[0016] In the following description, numerous specific details are provided to provide a more thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention can be practiced without one or more of these details. In other instances, certain technical features known in the art are not described to avoid confusion with the present invention.

[0017] The prefabricated anchor rod sealing reinforcement structure for the compressed air energy storage reservoir proposed in this embodiment mainly includes three parts: an elastic paddle 11 supporting structure 1, a detachable high-ductility movable slurry bag structure 2, and a hollow side wall prefabricated anchor rod structure 3 with holes.

[0018] Its two ends are fixed to two adjacent pieces of concrete using first expansion bolts 12, forming an upwardly arched elastic paddle 11 load-bearing structure. The first expansion bolts 12 are stainless steel countersunk expansion bolts, and the elastic paddle 11 is made of a material with high ductility and high deformation properties, in this case EPDM rubber. Its main function is to provide a certain amount of support to support the ductile slurry bag 21 containing the fluid, so that the ductile slurry bag 21 does not sag due to the fluid's own weight. When squeezed by the gas inside the underground gas storage cavern, the elastic paddle 11 acts as a force transmission medium to transmit the gas pressure to the ductile slurry bag 21, causing the ductile slurry bag 21 to be squeezed into different shapes. The elastic paddle 11 does not affect the deformation of the ductile bag containing slurry or plastic fluid. The movable slurry bag structure 2 mainly consists of the slurry bag 21, a screw 22 connecting the slurry bag 21, and a second expansion bolt 23 fixing it to the bottom of the screw 22. In a further preferred embodiment, the grouting bag 21 is a detachable ductile grouting bag 21. In addition, the end of the prefabricated anchor rod has a thread that matches the screw 22 connected to the grouting bag 21. The two can be engaged and tightened to form a detachable ductile grouting bag device. The grouting bag 21 is made of a material with high ductility and high deformation properties, and rubber is used here. Its main function is to carry the fluid plastic fluid material and grouting material. When the surrounding rock 6 does not produce cracks during the cavern gas storage period, it only needs to be filled with plastic fluid. As the gas is injected, the slicing lining opens cracks under the gas pressure during the pressurization process. The high-ductility grouting bag 21 filled with plastic fluid will be squeezed at the crack of the concrete lining under the action of pressure, playing a sealing role. When the gas is released, the high-ductility grouting bag 21 is squeezed to the outside of the lining. When the cavern is inflated and squeezed in the early stage, the surrounding rock 6 of the cavern does not produce cracks at this time. At this time, the surrounding rock 6 is relatively dense, and the loss of grout can be ignored. The second expansion bolt 23 is a stainless steel countersunk bolt. To reinforce the highly ductile grouting bag 21 and prevent it from loosening and dislodging from the base of the screw 22, a stainless steel flat bar is also installed at the base of the bolt in a further preferred embodiment. The hollow sidewall perforated prefabricated anchor rod structure 3 is a prefabricated anchor rod with a centrally poured precast concrete interior, a sealed top, and a hole in the sidewall extending into the surrounding rock 6. In a further preferred embodiment, the sealing structure 33 at the top of the prefabricated anchor rod can be a sealing plate. When the underground gas storage is subjected to repeated cyclic air pressure loads for many years, causing cracks to appear in the surrounding rock 6, the high-ductility grouting bag 21 can be removed and the internal slurry can be replaced with grouting material that can reinforce the surrounding rock 6. When subjected to air pressure boosting, due to the flow properties of the slurry, the slurry will be squeezed and flow along the prefabricated anchor rods in the hollow side walls, and flow into the surrounding rock 6 along the holes opened in the side walls of the anchor rods extending into the surrounding rock 6, to reinforce the surrounding rock 6, increase the stability of the cavern and extend the life of the cavern.The hollow precast anchor bolts in the sidewalls are cast solid in the middle with concrete, which increases the anchor bolt's inherent strength and, in turn, the ultimate strength of the surrounding rock 6. Furthermore, a lubricating layer is provided inside the precast anchor bolts to ensure smooth flow of slurry and prevent slurry accumulation within the bolts. A cylindrical flexible waterproof sheet 5, typically made of asphalt wood, is installed between the segmented concrete lining and the anchor bolts to prevent wear and damage to the segmented concrete lining and anchor bolts during gas pressurization and release.

[0019] The center of the precast anchor is a solid body formed by pouring concrete, which is used to strengthen the anchor and enhance the effect of reinforcing the surrounding rock 6. The sidewalls are hollow structures with holes in them, allowing slurry to flow into the surrounding rock 6 through the holes. The sidewalls are coated with a lubricating layer. In a further preferred embodiment, the lubricating layer can be any coating with lubricating properties known in the art, such as a solid lubricating layer of ferrous sulfide.

[0020] The top of the prefabricated anchor rod is closed, so that the slurry flowing into the surrounding rock 6 flows out from the side, and when the detachable high-ductility slurry bag 21 is used to improve the sealing performance, it ensures the loss and outflow of plastic fluid without affecting the sealing of the segmented lining seams by the slurry bag.

[0021] An anchor rod storage position is reserved in the surrounding rock 6 of the underground gas storage reservoir, and the prefabricated anchor rod is placed in the reserved diversion hole, and the hole wall just fits the outer wall of the anchor rod.

[0022] The bottom support at the bottom of the screw 22 will not affect the sealing of the cracks produced by the squeezing of the slurry-bearing cloth bag on the sliced ​​lining.

[0023] As described above, although the present invention has been shown and described with reference to specific preferred embodiments, it should not be interpreted as limiting the present invention itself. Various changes may be made to it in form and detail without departing from the spirit and scope of the present invention as defined in the appended claims.

Claims

1. A compressed air energy storage underground gas storage sealing reinforcement structure, characterized in that include: The supporting structure has a predetermined bending curvature and supporting force, and can perform corresponding supporting and limiting support operations; The movable slurry bag structure is movably connected to the supporting structure, has a predetermined deformation force and bearing space, and can perform corresponding bearing and deformation coordination operations; The prefabricated anchor rod structure has a predetermined operating length and supporting force, and is connected to the movable slurry bag structure. The side wall is hollow and can perform corresponding connection and positioning operations.

2. A sealed and reinforced structure for underground compressed air energy storage according to claim 1, characterized in that: The supporting structure includes an elastic pick and a first expansion bolt; the elastic pick has a predetermined bending arc and operating length, and can perform corresponding supporting operations; the first expansion bolt is connected to the elastic pick, and there are multiple of them, which are used for mutual communication between the elastic pick and the concrete lining.

3. A sealed and reinforced structure for underground compressed air energy storage according to claim 2, characterized in that: The movable slurry bag structure includes a slurry bag, a screw, and a second expansion bolt; the slurry bag has a predetermined bearing space and deformation force, and is attached to the elastic pick to perform corresponding bearing and limiting operations; The screw is connected to the slurry bag and extends a predetermined distance outside the slurry bag, and there are multiple screws, which can perform corresponding connection and positioning operations; the second expansion bolt is connected to the screw, has a predetermined operating length and supporting force, and there are multiple screws, which can perform corresponding positioning operations.

4. The compressed air energy storage underground gas storage sealing and reinforcement structure according to claim 1, characterized in that: The prefabricated anchor rod structure is hollow and has a predetermined working length, and a plurality of through holes are provided on the surface of the side wall; the prefabricated anchor rod is threadedly connected to the movable grout bag structure.

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