Sealing lining of underground gas storage and compressed air energy storage power station

Abstract

The utility model discloses a sealing lining of an underground gas storage and a compressed air energy storage power station, and relates to the technical field of underground gas storage, the sealing lining of the underground gas storage comprises a main body, the main body comprises at least one group of pipe joints, and adjacent pipe joints are welded; the pipe joint comprises at least two sets of first pipe pieces, the first pipe pieces are made of steel plates with smooth surfaces, and every two first pipe pieces are connected end to end and welded. Welding seams between the adjacent first pipe pieces are longitudinal seams, and the longitudinal seams between the adjacent pipe sections are arranged in a staggered mode. The compressed air energy storage power station comprises an underground gas storage which comprises the sealing lining. The sealing lining of the underground gas storage solves the problem that an existing sealing lining of the underground gas storage is easy to crack, and has the technical effects of being not easy to crack and leak.

Description

Technical Field

[0001] This utility model relates to the field of compressed air energy storage technology, and in particular to a sealed lining for an underground gas storage facility and a compressed air energy storage power station. Background Technology

[0002] Compressed air energy storage power stations generate electricity using compressed air energy storage systems, a technology that utilizes compressed air for energy storage. During energy storage, an electric motor drives a multi-stage compressor to compress air to high pressure and store it in a storage device, completing the conversion of electrical energy into air pressure energy. During energy release, the compressed air is released from the storage device and fed into a multi-stage expander to perform work, completing the conversion of air pressure energy into electrical energy. One method of implementing the storage device is to construct an underground artificial cavern, i.e., an underground gas storage facility, which has the advantage of large storage capacity and is more suitable for large-scale compressed air energy storage systems.

[0003] The underground gas storage facility is located within underground rock mass. A cavern for the storage facility is created by blasting within the rock mass, with the cavern's interior walls formed by the surrounding rock. The underground gas storage facility is constructed within this surrounding rock area. The innermost layer of the underground gas storage facility is a sealed lining, used to seal medium- and high-pressure gases. Concrete is backfilled between the sealed lining and the surrounding rock to secure the underground gas storage facility to the surrounding rock area. The sealed lining seals the compressed air, while the surrounding rock layer bears the pressure, and the high pressure within the compressed air is transferred to the surrounding rock through the concrete layer.

[0004] The sealing lining of current underground gas storage facilities is prone to cracking. Cracks in the sealing lining can lead to cracks in the concrete, which can cause compressed air to leak from the sealing lining and allow groundwater from the surrounding rock area to flow into the sealing lining, thus causing the underground gas storage facility to fail. Summary of the Invention

[0005] The purpose of this invention is to provide a sealed lining for underground gas storage facilities that are less prone to cracking and leakage.

[0006] To achieve this objective, on the one hand, a sealing liner for an underground gas storage facility is provided, wherein the sealing liner is welded from multiple tube segments, the tube segments being made of smooth steel plates; the weld seams of the sealing liner include an circumferential seam around the sealing liner and longitudinal seams intersecting the circumferential seam, with adjacent longitudinal seams staggered.

[0007] Furthermore, the surface of the tube segment includes a welding area and a pre-coated area; the welding area is a region that is translated inward by 80-200 mm from each side of the tube segment, and the area surrounded by the inner side of the welding area is the pre-coated area. The pre-coated area has an anti-corrosion coating pre-fabricated in the factory, and after at least two tube segments are welded, the anti-corrosion material is applied to the welding area on site.

[0008] Furthermore, the segments are made of high-strength steel.

[0009] Furthermore, a stiffening ring is provided on the outer side of the tube segment, and the inner ring of the stiffening ring is welded to the tube section.

[0010] Furthermore, the stiffening ring is provided with at least one drain hole, which is arranged close to the inner ring of the stiffening ring.

[0011] Furthermore, the sealing liner includes a tube section, and the tube segment includes a first tube segment; the tube section is formed by welding multiple first tube segments that unfold into rectangles, and the circumferential seam is formed by welding two tube sections together.

[0012] Furthermore, two sets of stiffening rings are provided on the outer side of one set of the pipe sections, and the two sets of stiffening rings are respectively located at the two open ends of the pipe sections.

[0013] Furthermore, the thickness of the first segment is 15-55 mm.

[0014] Furthermore, the sealing liner includes a head, and the tube segment includes a second tube segment; the head is spherical and is formed by welding multiple irregularly shaped second tube segments.

[0015] On the other hand, a compressed air energy storage power station is also provided, including an underground gas storage facility, the underground gas storage facility including the sealed lining of the underground gas storage facility of any of the above.

[0016] One of the above technical solutions has the following advantages or beneficial effects: The sealing lining of the underground gas storage facility is welded from smooth steel plates, which absorb the energy of expansion and deformation caused by pressure under pressure through the plasticity of the steel plates. Because the first segment has a flat base surface, the contact surface between the outer side of the sealing lining and the concrete is flat when backfilling concrete, allowing the concrete layer to uniformly transfer stress. Furthermore, due to the staggered arrangement of longitudinal joints between adjacent segments, the sealing lining in this embodiment has good stress conditions, can disperse locations prone to stress concentration, minimizes stress concentration in the sealing lining, and is less prone to cracking and leakage during operation, resulting in good safety and a long service life. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the first segment in this utility model;

[0018] Figure 2 This is a schematic diagram of the sealing liner of this utility model;

[0019] Figure 3 An embodiment of a sealed lining for a gas storage cavity that is an annular flat cavity is shown.

[0020] In the figure: 1-First segment; 2-Longitudinal seam; 3-Circumferential seam; 4-Reinforcing ring; 5-Drainage hole; 6-Pre-coated area inside the first segment; 7-Pre-coated area outside the first segment; 8-Segment; 9-Second segment; 10-Welding area inside the first segment; 11-Welding area outside the first segment; 12-End cap; 13-Sealing liner; 14-End cap weld; 15-Welded end. Detailed Implementation

[0021] To make the technical problems solved by this utility model, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the embodiments of this utility model will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0022] The underground gas storage facility is located within underground rock mass, where a cavern for construction is blasted out. After the cavern is blasted out, its inner wall is surrounded by rock, and the underground gas storage facility is constructed within this rock zone. The basic construction process for an underground gas storage facility is as follows: First, the innermost sealing lining is constructed to seal medium- and high-pressure gases. Then, concrete is backfilled between the outer wall of the sealing lining and the surrounding rock to fix the underground gas storage facility to the surrounding rock area. In this underground gas storage facility, the sealing lining seals compressed air, the surrounding rock layer bears the pressure, and during inflation, the high pressure within the compressed air is transferred to the surrounding rock through the concrete layer.

[0023] Considering the expansion under pressure, the sealing lining of underground gas storage facilities typically employs a flexible steel structure, such as an arched corrugated lining layer that expands with increasing gas pressure. However, when backfilling concrete onto the outside of this lining, the uneven surface between the outer side of the lining and the concrete creates an uneven base, leading to uneven stress transfer between the steel lining and the concrete during operation. This uneven stress on the concrete during operation will cause both the sealing lining and the concrete layer to crack easily. Cracks in the sealing lining will directly cause leakage in the gas storage facility. While cracks in the concrete layer may not immediately affect the lining's sealing performance, groundwater from the surrounding rock will seep through the cracks in the concrete layer, soaking and eroding the lining, also causing leakage.

[0024] An underground gas storage facility may include at least one area for gas storage. When it includes multiple areas for gas storage, each storage area is also referred to as a gas storage cavern. The sealing liner in this embodiment is used for sealing the gas storage cavern and is typically located in the innermost layer of the cavern. The sealing liner is welded from multiple tubular segments. The welds of the sealing liner include annular seams 3 around the main body of the sealing liner and longitudinal seams 2 intersecting the annular seams. Adjacent longitudinal seams 2 are staggered. The gas storage cavern can be a horizontal cavern, a vertical shaft, or a barrel shape. Horizontal caverns can be annular or elongated. Figure 2 An embodiment of a sealed lining for a gas storage cavity that is a long, flat, rectangular cavity is shown. Figure 3 An embodiment of a sealed lining for a gas storage cavity that is an annular flat cavity is shown.

[0025] The sealed lining of the underground gas storage facility in this embodiment is welded from multiple segments, each made of smooth steel plate. The steel plate's plasticity absorbs the energy from the expansion and deformation of the sealed lining under pressure. Because the segments have a flat base surface, the contact surface between the outer side of the sealed lining and the concrete is smooth during backfilling, allowing the concrete layer to uniformly transfer stress. Furthermore, due to the staggered longitudinal joints between adjacent segments, the sealed lining in this embodiment has good stress conditions, effectively dispersing stress concentration points and minimizing stress concentration within the sealed lining. This reduces the likelihood of cracking and leakage during operation, resulting in good safety and a long service life. Figure 2 and Figure 3 The sealing liner includes a tube section 8, and the tube segments include first tube segments. Each tube section is formed by welding multiple first tube segments 9, which unfold to a rectangle. Two tube sections are welded together to form an circumferential seam 3. Preferably, the first tube segment 1 is arc-shaped, unfolding to a rectangle. Two to five first tube segments 1 are welded together to form a tube section 8, resulting in a tube section 8 with a diameter of 5-20 meters and a large gas storage capacity. Furthermore, the thickness of the first tube segment 1 is 15-55 mm, providing good thermal stability. The aforementioned sealing liner can absorb the energy caused by expansion and deformation under pressure through its own plasticity and can withstand the external water pressure of the steel liner for a long time. Figure 2 As shown, the longitudinal seams 2 of adjacent pipe sections 8 are staggered, which can disperse the locations where stress concentration is likely to occur and avoid leakage of the sealing lining due to stress concentration.

[0026] like Figure 2 The sealed lining of some shaped gas storage cavities includes a head 12, and the tube segments include second tube segments. The head is spherical and is formed by welding multiple irregularly shaped second tube segments. For example... Figure 2As shown, the end cap 12 is hemispherical and is welded from multiple irregularly shaped second segments 9. The second segments 9 are also made of smooth steel plates, and the second segments 9 and the first segment 1 can be made of the same steel plate. The diameter of the end cap 12 matches the diameter of the pipe section 8. Preferably, the thickness of the second segment 9 is greater than the thickness of the first segment 1, by 5-15 mm. The weld between the second segments 9 is called the end cap weld 14. In this embodiment, the longitudinal seam 2 and the end cap weld 14 are staggered, which can also disperse the locations where stress concentration is likely to occur, minimizing stress concentration in the sealing liner 13.

[0027] Furthermore, the tunnel segments are made of high-strength steel. High-strength steel refers to steel whose tensile strength and yield strength exceed a certain limit, such as a nominal yield strength f > 420 MPa, while also possessing good toughness, ductility, and processing properties.

[0028] Furthermore, both the outer and inner sides of the sealing liner 13 are coated with an anti-corrosion coating. The outer side of the sealing liner 13 may contain groundwater, and the interior of the sealing liner 13 may contain condensate. Both groundwater and condensate may carry corrosive chemical components. To prevent groundwater and internal condensate from corroding the steel liner and affecting its strength, in this embodiment, both the outer and inner sides of the sealing liner 13 are coated with an anti-corrosion coating. Preferably, the material for the anti-corrosion coating on the inner side of the sealing liner 13 is an ultra-thick, solvent-free, wear-resistant epoxy paste, and the material for the anti-corrosion coating on the outer side of the sealing liner 13 is an inorganic modified cement slurry.

[0029] The anti-corrosion coating on the surface of the sealing liner 13 can be applied after the sealing liner welding is completed. Alternatively, both the inner and outer surfaces of the tube segment include a welding area and a pre-coated area. The welding area is a region shifted inward by 80-200 mm from each side of the tube segment. The area enclosed by the inner side of the welding area is the pre-coated area. The anti-corrosion coating in the pre-coated area is pre-fabricated in the factory. After at least two tube segments are welded, the anti-corrosion material in the welding area is applied on-site. To speed up the on-site coating time of the anti-corrosion coating, the inner and outer anti-corrosion coatings can be partially pre-fabricated in the factory. Considering that the coating of the tube segment containing the anti-corrosion coating will be damaged during welding, a welding area and a pre-coated area are set on the inner side of the tube segment. The anti-corrosion coating in the pre-coated area on the inner side of the tube segment is pre-fabricated in the factory, while the welding area is not coated at all. Instead, the anti-corrosion material is applied on-site after welding is completed. Preferably, the thickness of the pre-coated area is 100-1000 mm, and more preferably, the thickness of the pre-coated area is 500-800 mm. Preferably, the shape of the welding area on the inner side of segment 1 is consistent with the shape of the welding area on the outer side of segment 1. Furthermore, both the first segment 1 and the second segment 9 are provided with welding areas and pre-coating areas after cutting and before welding. Figure 1The welding areas 10 on the inner side of the first segment and 11 on the outer side of the first segment are areas shifted inward by 80-200 mm from each side of the first segment 1. The area enclosed by the inner side of the welding areas is the pre-coating area. The pre-coating areas 6 on the inner side of the first segment and 7 on the outer side of the first segment have pre-formed anti-corrosion coatings in the factory. The welding areas are not coated at all, but the anti-corrosion material is applied on-site after welding is completed.

[0030] like Figure 1 and Figure 2 At least one set of stiffening rings 4 are provided on the outer side of the pipe section 8, and the stiffening rings 4 are set perpendicular to the longitudinal joint. The stiffening rings 4 are used to reduce the deformation of the pipe section 8 under the action of external water pressure during construction and operation, and to improve the gripping force of the steel lining sealing layer when backfilling concrete. In particular, when the underground gas storage is used in a compressed air energy storage system, the underground gas storage is to be circulated and discharged. The stiffening rings 4 on the outer side of the pipe section 8 can prevent the sealing lining 13 from slipping under the circulated and discharged conditions of the underground gas storage.

[0031] In this embodiment, the stiffening ring 4 can be welded to the outside of the pipe section 8 after the pipe segments are assembled into a pipe section. For example... Figure 1 In this embodiment, the stiffening ring can be divided into multiple segments. After welding a portion of the stiffening ring 4 to the outside of each first segment 1, the first segments 1 are then assembled into a pipe section. In this case, the end of the portion of the stiffening ring 4 on the outside of the first segment 1 does not exceed the longitudinal seam of the first segment 1; that is, the length of the portion of the stiffening ring 4 on the outside of the first segment 1 is less than the length of the first segment 1. After a pipe section 8 is welded, the stiffening rings 4 on both sides of the longitudinal seam are connected by a segment of stiffening ring 4 of corresponding length. This segment of stiffening ring 4 is welded to the pipe section 8 at the longitudinal seam and also welded to the stiffening rings 4 on the first segments 1 on both sides of the longitudinal seam.

[0032] Preferably, the height of the stiffening ring 4 is 10-30 cm and the thickness is 10-30 mm. Preferably, 1 to 5 sets of stiffening rings 4 are provided on a pipe section 8, and the number of stiffening rings 4 is determined according to the width of the pipe section 8. Figure 1 and Figure 2 This shows the case where there are two sets of stiffening ring 4, such as Figure 1 and Figure 2 As shown, there are two sets of stiffening rings 4, with the two sets of stiffening rings 4 located on both sides of the pipe section 8. Furthermore, the stiffening rings 4 are installed at a position 400-800 mm shifted from the open end of the pipe section 8.

[0033] Preferably, the stiffening ring 4 is provided with at least one drain hole 5 to facilitate drainage or installation of drainage components. Preferably, the drain hole 5 is semi-circular with a radius of 50-100 mm. The drain hole is located close to the pipe section.

[0034] Preferably, an anti-corrosion coating is applied to the surface of the stiffening ring 4. If the stiffening ring 4 can be welded to the outside of the pipe section 8 after the pipe segments are assembled into a pipe section, then an anti-corrosion coating is applied to its surface after welding. If the stiffening ring 4 is divided into multiple segments, then the portion of the stiffening ring 4 fixed to the outside of the first pipe segment 1 is coated with an anti-corrosion coating before assembly. Further, welding ends 15 are provided at both ends of the portion of the stiffening ring fixed to the outside of the first pipe segment 1, and the welding ends are not coated with an anti-corrosion coating. Preferably, the welding ends are 50-200 mm inside the end of the portion of the stiffening ring.

[0035] This embodiment Figure 2 The construction method for the sealed inner side 13 of the strip-shaped gas storage cavity shown in the figure is as follows:

[0036] S1: Transport the first segment 1 and the second segment 9 to the workshop located in the underground gas storage facility;

[0037] S2: Through the assembly, welding and turning of equipment such as gantry cranes and fixed gantry frames, several first tube segments 1 are welded into tube sections 8, and several second tube segments 9 are welded into end caps 12.

[0038] S3: Transport the assembled pipe section 8 to the installation location of the underground gas storage facility. At the installation location, weld pipe section 8 to the adjacent pipe section 8. Weld pipe section 8 to end cap 12 at the annular opening.

[0039] This embodiment also provides a compressed air energy storage power station, which uses a compressed air energy storage system to store and generate electricity. The gas storage device of the compressed air energy storage power station adopts an underground gas storage tank, and the sealing layer of the underground gas storage tank adopts the sealing structure of this embodiment. Because the sealing structure is not prone to cracking and leakage during operation, it has good safety and long service life. Even under the condition of frequent gas circulation and discharging, the underground gas storage tank can operate stably and continuously for a long time, making it suitable for long-term, large-scale compressed air energy storage power stations.

[0040] Therefore, the sealed lining of the underground gas storage facility in this embodiment possesses high structural strength, good toughness, and excellent thermal stability. It can continuously and stably store high-temperature, high-pressure compressed gas for extended periods, is less prone to cracking and leakage, evenly distributes the pressure of the high-pressure gas to the surrounding rock, and can withstand external water pressure over long periods. Furthermore, it can adapt to the frequent charging and discharging conditions and potential localized high temperatures that may occur during the operation of the compressed air energy storage power station. The outer side of the sealed lining has reinforcing rings, which can withstand a certain amount of external water pressure during operation and enhance the bond between the concrete and the steel lining during backfilling and operation, preventing displacement of the steel lining. Both the inner and outer sides of the sealed lining have anti-corrosion coatings to prevent groundwater and internal condensation from corroding the steel lining and affecting its strength.

[0041] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0042] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0043] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A sealed inner lining for an underground gas storage facility, characterized in that, The sealing liner is welded from multiple tubular segments, which are made of smooth steel plates. The welds of the sealing liner include a circumferential weld around the sealing liner and longitudinal welds intersecting the circumferential welds, with adjacent longitudinal welds staggered.

2. The sealed inner lining of the underground gas storage facility according to claim 1, characterized in that, The surface of the tube segment includes a welding area and a pre-coated area; the welding area is a region that is shifted inward by 80-200 mm from each side of the tube segment, and the area surrounded by the inner side of the welding area is the pre-coated area. The pre-coated area has an anti-corrosion coating pre-fabricated in the factory, and after at least two tube segments are welded, the anti-corrosion material is applied to the welding area on site.

3. The sealed inner lining of the underground gas storage facility according to claim 1, characterized in that, The segments are made of high-strength steel.

4. The sealed inner lining of the underground gas storage facility according to claim 1, characterized in that, The outer side of the tube segment is provided with a stiffening ring, and the inner ring of the stiffening ring is welded to the tube segment.

5. The sealed inner lining of the underground gas storage facility according to claim 4, characterized in that, The stiffening ring is provided with at least one drain hole, which is arranged close to the inner ring of the stiffening ring.

6. The sealed inner lining of the underground gas storage facility according to claim 1, characterized in that, The sealing liner includes a tube section, and the tube segment includes a first tube segment; the tube section is formed by welding multiple first tube segments that unfold into rectangles, and the circumferential seam is formed by welding two tube sections together.

7. The sealed inner lining of the underground gas storage facility according to claim 6, characterized in that, Two sets of stiffening rings are provided on the outer side of one set of the pipe sections, and the two sets of stiffening rings are respectively located at the two open ends of the pipe sections.

8. The sealed inner lining of the underground gas storage facility according to claim 6, characterized in that, The thickness of the first segment is 15-55 mm.

9. The sealed inner lining of the underground gas storage facility according to claim 1, characterized in that, The sealing liner includes a head, and the tube segment includes a second tube segment; the head is spherical and is formed by welding multiple irregularly shaped second tube segments.

10. A compressed air energy storage power station, characterized in that, It includes an underground gas storage facility, wherein the underground gas storage facility includes the sealed lining of the underground gas storage facility as described in any one of claims 1-9.

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