Underground gas storage with inner support

Abstract

The invention discloses an underground gas storage with an inner support, belongs to the technical field of underground gas storage, and can solve the problems that when a sealing layer of an existing underground gas storage bears external pressure, the sealing layer with a small thickness is unstable and damaged, and the sealing layer with a large thickness increases engineering investment. The underground gas storage comprises a lining; the sealing layer is arranged on the inner wall of the lining; the telescopic supporting rings are sequentially arranged on the inner side of the sealing layer in the hole length direction of the underground gas storage, and each telescopic supporting ring is coaxial with a hole body of the underground gas storage and tightly attached to the inner wall of the sealing layer; the telescopic supporting ring comprises a plurality of corrugated plates distributed annularly and a plurality of telescopic pieces used for connecting every two adjacent corrugated plates, and the telescopic pieces are connected to the fluctuating ends of the corrugated plates. The telescopic supporting ring is used for supporting the sealing layer all the time in the expansion or contraction process of the underground gas storage. The invention is used for underground gas storages.

Description

Technical Field

[0001] The invention relates to an underground gas storage with internal support, belonging to the technical field of underground gas storage. Background Art

[0002] With the continuous growth of energy demand and the pursuit of clean energy, compressed air energy storage technology, as a large-scale energy storage technology, has received widespread attention. The gas storage reservoir is a key component of the compressed air energy storage power station, and its safety and stability directly affect the performance of the entire energy storage system. Underground gas storage reservoirs all need to be sealed with a sealing layer. Due to the large underground burial depth of underground gas storage reservoirs, most of them are below the groundwater level. When the gas storage reservoir is in a pressure-free state or the groundwater pressure is higher than the pressure in the reservoir, the sealing layer is subjected to external pressure. At this time, the thinner sealing layer will become unstable and damaged, and the thicker sealing layer will undoubtedly increase the project investment exponentially. Summary of the invention

[0003] The present invention provides an underground gas storage with internal support, which can solve the problem that when the sealing layer of the existing underground gas storage is subjected to external pressure, a thinner sealing layer will become unstable and damaged, while a thicker sealing layer will increase the project investment.

[0004] The present invention provides an underground gas storage with internal support, the underground gas storage comprising:

[0005] Lining;

[0006] A sealing layer, disposed on the inner wall of the lining;

[0007] A plurality of retractable support rings are sequentially arranged on the inner side of the sealing layer along the length direction of the underground gas storage hole, each retractable support ring is coaxial with the hole body of the underground gas storage hole and is in close contact with the inner wall of the sealing layer;

[0008] The retractable support ring includes a plurality of corrugated plates distributed in a ring shape and a plurality of retractable parts for connecting every two adjacent corrugated plates, wherein the retractable parts are connected to the undulating ends of the corrugated plates; the retractable support ring is used to always support the sealing layer during the expansion or contraction of the underground gas storage reservoir.

[0009] Optionally, the corrugated plate is in a sinusoidal wave shape.

[0010] Optionally, in the circumferential direction of the cavity of the underground gas storage, the radius of curvature of the corrugated plate is the same as the radius of curvature of the cavity of the underground gas storage.

[0011] Optionally, the wave height of the corrugated plate is determined according to the allowable stress of the corrugated plate, the number of corrugations of the corrugated plate and the design internal pressure of the underground gas storage;

[0012] The wavelength of the corrugated plate is determined according to the wave height of the corrugated plate.

[0013] Optionally, the thickness of the corrugated plate is determined according to the internal pressure thickness and the external pressure thickness;

[0014] The internal pressure thickness is determined according to the design internal pressure of the underground gas storage reservoir, the inner diameter of the underground gas storage reservoir, the allowable stress of the corrugated plate and the corrugation influence coefficient; wherein the corrugation influence coefficient is the ratio of the principal stress of the corrugated plate to the principal stress of a flat plate of the same material and size;

[0015] The external pressure thickness is determined according to the maximum external pressure of the corrugated plate, the inner diameter of the underground gas storage reservoir, the elastic modulus and Poisson's ratio of the corrugated plate.

[0016] Optionally, a sealing plate is fixed to the undulating end of the corrugated plate, and the sealing plate covers the undulating end of the corrugated plate;

[0017] The telescopic member is connected to the sealing plates at the ends of two adjacent corrugated plates.

[0018] Optionally, the telescopic member is connected to the sealing plate via a snap fastener.

[0019] Optionally, the telescopic members of two adjacent telescopic support rings are staggered.

[0020] Optionally, the telescopic member is a spring or a hydraulic telescopic rod.

[0021] Optionally, the corrugated plate is made of alloy steel.

[0022] The beneficial effects that the present invention can produce include:

[0023] The underground gas storage reservoir with internal support provided by the present invention has multiple retractable support rings arranged on the inner side of the sealing layer. Since the retractable support rings are connected by multiple corrugated plates and retractable parts, when the underground gas storage reservoir expands or contracts, the retractable parts can adjust the length of the entire retractable support ring so that the corrugated plates always support the sealing layer, thereby avoiding the thinner sealing layer from becoming unstable and damaged when under pressure, and also avoiding the problem of increasing engineering investment due to the use of a thick sealing layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of a cross-sectional structure of an underground gas storage reservoir with internal support provided in an embodiment of the present invention;

[0025] Figure 2 for Figure 1 Schematic diagram of the structure of the AA section;

[0026] Figure 3 for Figure 1 Schematic diagram of the structure of the middle BB section;

[0027] Figure 4 for Figure 1 Schematic diagram of the structure of the CC section.

[0028] Reference numerals:

[0029] 1. Corrugated plate; 2. Telescopic parts; 3. Sealing layer; 4. Lining; 5. Underground gas storage. DETAILED DESCRIPTION

[0030] The present invention is described in detail below in conjunction with embodiments, but the present invention is not limited to these embodiments.

[0031] The embodiment of the present invention provides an underground gas storage with internal support, such as Figures 1 to 4 As shown, the underground gas storage comprises:

[0032] Lining 4; in practical applications, it is generally a concrete lining.

[0033] The sealing layer 3 is arranged on the inner wall of the lining 4 .

[0034] A plurality of retractable support rings are sequentially arranged on the inner side of the sealing layer 3 along the length direction of the underground gas storage reservoir 5, each of the retractable support rings is coaxial with the hole of the underground gas storage reservoir 5, and is in close contact with the inner wall of the sealing layer 3; the retractable support ring comprises a plurality of corrugated plates 1 distributed in a ring shape and a plurality of retractable parts 2 for connecting every two adjacent corrugated plates 1, and the retractable parts 2 are connected to the undulating ends of the corrugated plates 1; the retractable support ring is used to always support the sealing layer 3 during the expansion or contraction of the underground gas storage reservoir 5.

[0035] The corrugated plate 1 can be made of high-strength, corrosion-resistant alloy steel, which can withstand high pressure (self-stabilizing and able to withstand sufficient external pressure during the long-term operation of the underground gas storage 5), and has good durability in a humid or corrosive gas storage environment. At the same time, considering that the corrugated structure needs good cold bending performance, this steel can also meet the processing requirements.

[0036] The telescopic member 2 needs to have high toughness and a certain elasticity. A spring or a hydraulic telescopic rod with telescopic performance can be selected. It has good elastic limit and fatigue strength, can maintain stable performance during frequent telescopic process, and keep the telescopic support ring in close contact with the sealing layer 3 at all times, ensuring that the small pieces of the corrugated plate 1 are firmly connected and adaptable to deformation.

[0037] In the embodiment of the present invention, the corrugated plate 1 adopts a sinusoidal wave shape, which can improve the compression resistance and deformation adaptability when subjected to pressure. According to the shape and size of the gas storage reservoir, the circular corrugated plate is divided into 3 to 8 small pieces, and the wave height and wavelength of the corrugated plate 1 need to be determined by comprehensively considering factors such as the inner diameter of the gas storage reservoir, the operating pressure, and the characteristics of the steel.

[0038] In practical applications, the wave height of the corrugated plate 1 is determined according to the allowable stress of the corrugated plate 1 , the number of corrugations of the corrugated plate 1 and the design internal pressure of the underground gas storage reservoir 5 ; the wavelength of the corrugated plate 1 is determined according to the wave height of the corrugated plate 1 .

[0039] Specifically, the wave height of corrugated plate 1 ,wavelength ;in, is the allowable stress of the corrugated plate 1, is the number of corrugations of corrugated plate 1, is the area reduction coefficient (usually 0.8~0.9 based on experience), is the designed internal pressure of the underground gas storage 5, is the correlation coefficient between wavelength and wave height (generally 5~10 based on experience).

[0040] Each small piece of corrugated plate 1 needs to fit the inner wall of the gas storage hole. In the circumferential direction of the hole of the underground gas storage 5, the curvature radius of the corrugated plate 1 is The curvature radius of the cavern of the underground gas storage 5 same.

[0041] In the embodiment of the present invention, the thickness of the corrugated plate 1 can be determined according to the internal pressure thickness and the external pressure thickness.

[0042] Among them, the internal pressure thickness is determined according to the designed internal pressure of the underground gas storage reservoir 5, the inner diameter of the underground gas storage reservoir 5, the allowable stress of the corrugated plate 1 and the corrugation influence coefficient; the corrugation influence coefficient is the ratio of the principal stress of the corrugated plate 1 to the principal stress of a flat plate of the same material and size.

[0043] The external pressure thickness is determined according to the maximum external pressure of the corrugated plate 1 , the inner diameter of the underground gas storage reservoir 5 , the elastic modulus of the corrugated plate 1 , and the Poisson's ratio.

[0044] Specifically, for the thickness of the corrugated plate 1, the larger value of the two cases is taken into consideration: the case of bearing internal pressure during operation and the case of bearing external pressure during maintenance operation. When considering internal pressure, based on the thin-walled cylinder theory, the influence of the corrugation shape on the bearing capacity is considered and the corrugation influence coefficient is introduced. , this coefficient can be obtained through numerical simulation analysis, that is, (Numerical simulation of the same size conditions, the principal stress of corrugated plate 1 The principal stresses of a plate of the same material and size are The internal pressure thickness of the corrugated plate 1 is ,in is the design internal pressure of the underground gas storage 5, is the inner diameter of the underground gas storage 5, is the allowable stress of the corrugated plate 1; when operating under external pressure, the safety reduction factor is introduced by using the cylindrical shell structure theory under external pressure and combining the importance of the project and the impact of construction. (value ranges from 0.5 to 0.9), then , is the maximum external pressure acting on the corrugated plate 1 calculated by numerical simulation, is the elastic modulus of the corrugated plate 1, is Poisson's ratio, from which the minimum thickness under external pressure can be obtained , i.e. the external pressure thickness; finally, the larger value under the two calculation conditions is taken as the design thickness of the corrugated plate 1.

[0045] Preferably, a sealing plate is fixed to the undulating end of the corrugated plate 1 , and the sealing plate covers the undulating end of the corrugated plate 1 ; the telescopic member 2 is connected to the sealing plates at the ends of two adjacent corrugated plates 1 .

[0046] In practical applications, steel plates are used as sealing plates.

[0047] The two ends of the divided corrugated plate 1 are sealed with steel plates, which can increase the strength of the divided corrugated plate 1 and is also conducive to the installation of the telescopic member 2.

[0048] The sealing plates of adjacent corrugated plates 1 are connected together by high-strength springs. The length of the spring should be designed according to the annular deformation results of the chamber in the numerical calculation. According to Hu Ke's law, the deformation formula is:

[0049] ;

[0050] in, is the deformation of the telescopic member 2; is the external force acting on the telescopic member 2; is the cross-sectional area of ​​the telescopic member 2; is the original length of telescopic member 2; is the elastic modulus of the telescopic member 2.

[0051] Given the annular deformation, the annular deformation is averaged over each telescopic member 2 to obtain the original length of the telescopic member 2. .

[0052] Furthermore, the telescopic member 2 is connected to the sealing plate via a buckle.

[0053] The two ends of the telescopic member 2 are respectively fixed to the sealing plate of the segmented corrugated plate 1 by a conventional buckle structure, and the buckle method is convenient for disassembly and assembly, and convenient for later maintenance. 2 to 3 telescopic members 2 can be installed on one side of each corrugated plate 1.

[0054] In the present invention, the advantage of dividing the corrugated plate 1 into several pieces is that when the gas storage expands or contracts, the corrugated plate 1 can expand or contract simultaneously without generating large stress and causing damage to the corrugated plate 1.

[0055] The benefit of providing the telescopic member 2 is that the length of the telescopic support ring is adjusted by utilizing the telescopic performance of the spring or hydraulic telescopic rod, so that the corrugated plate 1 and the sealing layer 3 are always in close contact.

[0056] The advantage of configuring the supporting plate as a corrugated plate 1 is that the thickness of the supporting plate can be reduced, and the rigidity of the steel plate can be increased by using the corrugated form, thereby improving the supporting strength.

[0057] The advantages of using steel plates to seal the two ends of the corrugated plate 1 are that the strength of the corrugated plate 1 can be increased and the installation of the telescopic member 2 is also facilitated.

[0058] The advantage of using a buckle structure to fix the telescopic member 2 is that it is easy to disassemble and assemble the telescopic member 2 and facilitate later maintenance.

[0059] When the telescopic support rings are actually installed, the telescopic members 2 of two adjacent telescopic support rings are staggered.

[0060] Specifically, refer to Figure 1 As shown, every A ring of retractable support rings is arranged every meter (the spacing can be set to 1m). In the circumferential direction of the cave, the annular corrugated plate is evenly divided into several pieces, and two adjacent corrugated plates 1 are connected by retractable parts 2.

[0061] During the layout process, measuring instruments are used to ensure that the center of each retractable support ring coincides with the axis of the cave, the rings remain parallel, and the error is controlled within ±1cm.

[0062] The width of the retractable support ring can be 50cm. The number of retractable support rings arranged in the axial direction is determined according to the length of the cave and the use requirements. In the axial direction, the joints of two adjacent retractable support rings should be staggered to avoid the joints being concentrated in the same position to improve the stability of the overall structure.

[0063] The present invention improves the compression resistance and deformation adaptability through the design of the corrugated plate 1 in a sinusoidal wave shape, and can effectively cope with the complex pressure environment of the gas storage.

[0064] The present invention comprehensively considers factors such as the inner diameter of the gas storage reservoir, the operating pressure, and the properties of the steel material to accurately calculate the wave height, wavelength, and thickness of the corrugated plate 1, thereby ensuring the safety and stability of the structure under different working conditions.

[0065] The telescopic member 2 of the present invention is made of a spring or a hydraulic telescopic rod with telescopic performance, which can always maintain stable performance during frequent telescopic processes, ensure a firm connection between the corrugated plates 1, adapt to structural deformation, and keep the corrugated plates 1 always in close contact with the sealing layer 3.

[0066] The present invention ensures the overall stability of the structure through reasonable circumferential and longitudinal arrangements, and the error control and staggered arrangement of joints further improve the reliability of the structure.

[0067] The present invention provides an inner support structure such as a telescopic support ring, which has a simple structure, is easy to disassemble and assemble, and is also convenient to maintain and overhaul.

[0068] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. An underground gas storage with internal support, characterized in that: The underground gas storage comprises: Lining; A sealing layer, disposed on the inner wall of the lining; A plurality of retractable support rings are sequentially arranged on the inner side of the sealing layer along the length direction of the underground gas storage hole, each retractable support ring is coaxial with the hole body of the underground gas storage hole and is in close contact with the inner wall of the sealing layer; The retractable support ring includes a plurality of corrugated plates distributed in a ring shape and a plurality of retractable parts for connecting every two adjacent corrugated plates, wherein the retractable parts are connected to the undulating ends of the corrugated plates; the retractable support ring is used to always support the sealing layer during the expansion or contraction of the underground gas storage reservoir.

2. The underground gas storage according to claim 1, characterized in that: The corrugated plate is in a sinusoidal wave shape.

3. The underground gas storage according to claim 1 or 2, characterized in that: In the circumferential direction of the cave of the underground gas storage, the curvature radius of the corrugated plate is the same as the curvature radius of the cave of the underground gas storage.

4. The underground gas storage according to claim 2, characterized in that: The wave height of the corrugated plate is determined according to the allowable stress of the corrugated plate, the number of corrugations of the corrugated plate and the designed internal pressure of the underground gas storage; The wavelength of the corrugated plate is determined according to the wave height of the corrugated plate.

5. The underground gas storage according to claim 2, characterized in that: The thickness of the corrugated plate is determined according to the internal pressure thickness and the external pressure thickness; The internal pressure thickness is determined according to the design internal pressure of the underground gas storage reservoir, the inner diameter of the underground gas storage reservoir, the allowable stress of the corrugated plate and the corrugation influence coefficient; wherein the corrugation influence coefficient is the ratio of the principal stress of the corrugated plate to the principal stress of a flat plate of the same material and size; The external pressure thickness is determined according to the maximum external pressure of the corrugated plate, the inner diameter of the underground gas storage reservoir, the elastic modulus and Poisson's ratio of the corrugated plate.

6. The underground gas storage according to claim 1 or 2, characterized in that: A sealing plate is fixed to the undulating end of the corrugated plate, and the sealing plate covers the undulating end of the corrugated plate; The telescopic member is connected to the sealing plates at the ends of two adjacent corrugated plates.

7. The underground gas storage according to claim 6, characterized in that: The telescopic member is connected to the sealing plate via a buckle.

8. The underground gas storage according to claim 1, characterized in that: The telescopic parts of two adjacent telescopic support rings are staggered.

9. The underground gas storage according to claim 1, characterized in that: The telescopic member is a spring or a hydraulic telescopic rod.

10. The underground gas storage according to claim 1, characterized in that: The material of the corrugated plate is alloy steel.

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