Compressed air energy storage abandoned roadway simulation system

Abstract

The application provides a compressed air energy storage abandoned roadway simulation system, and belongs to the technical field of energy storage simulation, which comprises a constant-temperature chamber, a test piece box, a gas permeable membrane unit and the like, and a roadway is directly formed in the test piece box, similar materials in the test piece box are extruded and compacted by means of the action of an initial support module and a pressure head, so that a simulated roadway surrounding rock and a roadway are formed, the formed roadway has an open end, is more operable, and can be installed with a strain gauge unit by means of another support module, and the installed strain gauge unit can more truly reflect the deformation condition of the roadway during compressed air energy storage.

Description

Technical Field

[0001] This invention belongs to the field of energy storage simulation technology, specifically relating to a compressed air energy storage waste roadway simulation system. Background Technology

[0002] Compressed air energy storage (CASS) boasts advantages such as low construction cost, small equipment footprint, low pollution, long storage cycle, and minimal site selection restrictions, making it considered one of the most promising large-scale energy storage technologies. However, the site selection for large-scale CASS storage is a major constraint on its development. Current applications primarily focus on underground salt caverns, such as the Huntorf CASS power station in Germany and the McIntosh CASS power station in the United States. However, the distribution of salt rock is extremely uneven. my country has a long history of coal mining, and due to the natural characteristics of coal seams, underground mining is the primary method. For coal mines, as resources are continuously mined, reaching the end of their service life inevitably leads to mine closure. The reuse of abandoned coal mines is urgent, and how to better develop and further utilize the underground space of abandoned coal mines is a focus of ongoing social attention and research. In this context, there is an urgent need to develop CASS technology for abandoned coal mines, not only to solve the technical challenges of the instantaneous and fluctuating nature of new energy power generation but also to effectively utilize the spatial resources of abandoned coal mines.

[0003] Currently, research on constructing compressed air energy storage power plants using the underground space of abandoned coal mines is limited, and most studies rely on numerical simulations. These methods often rely on assumptions and simplify the numerical simulations of on-site geological conditions, making it difficult to accurately and comprehensively reflect the actual on-site situation. Therefore, it is necessary to conduct physical simulations of compressed air energy storage in coal mine roadways. Furthermore, in the physical simulation experimental systems constructed based on existing methods, the formation of coal seam roadways is difficult and highly unstable after formation, differing significantly from real coal and rock, leading to inaccurate data.

[0004] Therefore, improvements to existing technologies are necessary. Summary of the Invention

[0005] To address the aforementioned problems in existing technologies, this invention provides a simulated system for compressed air energy storage in abandoned coal mine roadways. The purpose is to achieve a physical simulation of compressed air energy storage in coal mine roadways, to more realistically and accurately simulate compressed air energy storage in abandoned coal mines, and to provide an experimental basis for the research on compressed air energy storage in coal mine roadways.

[0006] To achieve the above technical objectives, the present invention adopts the following technical solution: A compressed air energy storage waste roadway simulation system includes a constant temperature chamber, a specimen box, roadway surrounding rock, a pressure plate unit, a pressure head, an air injection unit, an air inlet pipe, an information acquisition unit, an air outlet pipe, a power generation unit, a strain gauge unit, a breathable membrane unit, and a sealing unit. The specimen box is placed inside the constant temperature chamber and filled with roadway surrounding rock, forming a roadway in its center. The pressure plate unit inside the specimen box compresses the roadway surrounding rock towards the roadway under the action of the pressure head. The top of the specimen box is fixedly equipped with a spaced-apart vertical air inlet pipe and an air outlet pipe. One end of both the air inlet and outlet pipes extends downwards into the roadway, and the other end extends upwards out of the constant temperature chamber. The gas pipe and gas outlet pipe are connected to the gas injection unit and the power generation unit, respectively. One side of the tunnel is an open end, and a sealing unit is detachably installed at the open end to seal the tunnel. The constant temperature chamber and the specimen box are both equipped with openings that match the open end. A breathable membrane unit is bonded and fixed to the tunnel wall near the tunnel wall of the surrounding rock. Multiple strain gauge units are installed on the breathable membrane unit, and each strain gauge unit is communicatively connected to the information acquisition unit. The breathable membrane unit is in a first state before being bonded to the tunnel wall, and in a second state after being bonded to the tunnel wall. In the first state, the adhesive in the breathable membrane unit does not seep out. In the second state, the breathable membrane unit uses the adhesive inside to seep out to the tunnel wall to achieve solidification and bonding with the surrounding rock of the tunnel.

[0007] Compared with the prior art, the present invention has at least the following beneficial effects: The compressed air energy storage waste tunnel simulation system of the present invention forms the tunnel directly inside the test chamber. With the help of the initial support module, pressure head, etc., similar materials in the test chamber are compressed and compacted to form simulated tunnel surrounding rock and tunnel. The formed tunnel has an open end, which makes it more operable. Strain gauge units can be installed with the help of other support modules. The installed strain gauge units can more realistically reflect the deformation of the tunnel during compressed air energy storage. Attached Figure Description

[0008] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the main structure of the compressed air energy storage abandoned roadway simulation system provided by the present invention; Figure 2 yes Figure 1 Schematic diagram of the structure under section II; Figure 3 yes Figure 1 A partial structural diagram of the medium-permeable membrane unit in the first state; Figure 4 This is a schematic diagram of the structure of the epoxy resin microcapsules used in this invention; Figure 5 This is a schematic diagram of the structure of the present invention, in which the support structure (such as the initial support module or another support module) is placed inside the specimen box; The components are as follows: 1-Constant temperature chamber, 2-Specimen box, 3-Roadway surrounding rock, 4-Pressure plate unit, 5-Pressure head, 6-Gas injection unit, 7-Air inlet pipe, 8-Pressure gauge, 9-Valve, 10-Information acquisition unit, 11-Air outlet pipe, 12-Power generation unit, 13-Strain gauge unit, 14-Roadway, 15-Permeable membrane unit, 16-Sealing unit. 41-First pressure plate, 42-Second pressure plate, 43-Third pressure plate, 44-Fourth pressure plate 151 - Protective layer, 152 - Adhesive layer, 153 - Micro-permeable layer. Detailed Implementation

[0009] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0010] like Figures 1 to 5As shown, this invention provides a compressed air energy storage waste roadway simulation system, which includes a constant temperature chamber 1, a specimen box 2, roadway surrounding rock 3, a pressure plate unit 4, a pressure head 5, an air injection unit 6, an air inlet pipe 7, an information acquisition unit 10, an air outlet pipe 11, a power generation unit 12, a strain gauge unit 13, a breathable membrane unit 15, and a sealing unit 16. The specimen box 2 is placed inside the constant temperature chamber 1, and is filled with roadway surrounding rock 3, forming a roadway 14 in its center. The specimen box 2 is also equipped with a pressure plate unit 4, which can compress the surrounding rock 3 of the roadway 14 in the specimen box 2 under the action of the pressure head 5 on the specimen box 2. The top of the specimen box 2 is fixedly equipped with a spaced-apart vertical air inlet pipe 7 and an air outlet pipe 11. One end of the air inlet pipe 7 and the air outlet pipe 11 extends downward to the roadway 14, and the other end of the air inlet pipe 7 and the air outlet pipe 11 extends upward to the outside of the constant temperature chamber 1. The air inlet pipe extending to the outside of the constant temperature chamber 1... Pipe 7 and vent pipe 11 are connected to the gas injection unit 6 and the power generation unit 12, respectively. One side of the tunnel 14 is an open end. A sealing unit 16 is detachably installed at the open end to close the tunnel 14. The constant temperature chamber 1 and the specimen box 2 are both provided with openings that match the open end (not shown in the figure, which can be closed by means of hinges, etc.). A breathable membrane unit 15 is bonded and fixedly installed on the tunnel wall of the surrounding rock 3 near the tunnel 14. Multiple strain gauge units 13 are installed on the breathable membrane unit 15. Each strain gauge unit 13 is communicatively connected to the information acquisition unit 10. The breathable membrane unit 15 is in a first state before being bonded to the tunnel wall. The breathable membrane unit 15 is in a second state after being bonded to the tunnel wall. In the first state, the adhesive in the breathable membrane unit 15 does not seep out. In the second state, the breathable membrane unit 15 uses the adhesive inside to seep out to the tunnel wall to achieve solidification and bonding with the surrounding rock 3 of the tunnel.

[0011] It should be noted that current research on compressed air energy storage technology in abandoned coal mines generally relies on numerical simulations, which struggle to accurately and comprehensively reflect real-world conditions. While a few related physical simulation systems exist, the creation of the tunnels is extremely difficult, typically requiring the pre-fabrication of similar tunnel models (similar tunnel models and...). Figure 1 The surrounding rock 3 of the tunnel 14 shown is similar, but it may be a modular assembly. Then it is placed into the specimen box. In order to more closely resemble the real geological conditions, after the similar tunnel model is placed into the specimen box, its surrounding rock is usually subjected to loading and compression. This can easily lead to the collapse of the simulated tunnel. In addition, existing physical simulation systems usually bury sensors (such as strain gauge units 13) in the surrounding rock of the tunnel. Since the area of ​​stress deformation is more concentrated near the tunnel under the action of compressed air, the sensitivity and accuracy of the existing installation method are low. It can often only be detected when there is a large stress deformation.

[0012] Unlike existing technologies, the tunnel 14 of the present invention is formed directly inside the specimen chamber 2, by providing corresponding openings (set in the constant temperature chamber 1 and the specimen chamber 2) as described above. Figure 1 (On one side of the location of the sealing unit 16 shown), the initial support module (which can be rectangular in cross-section or of other shapes) used to form the tunnel 14 can be placed into the specimen box 2 through the opening. Then, the surrounding rock 3 (made of coal-rock similar material) is filled into the specimen box 2, so that the initial support module is covered by the surrounding rock 3 (at this time, the initial support module can be partially located at the opening, or even partially located outside the constant temperature chamber 1). Then, the surrounding rock 3 between the initial support module and the pressure plate unit 4 is compressed by the pressure head 5 on the specimen box 2, thereby forming a dense surrounding rock similar to the real strata. Then, the initial support module can be removed through the opening to form the tunnel 14 (the initial support module can be, for example, retractable, which is the prior art and will not be described in detail). The tunnel 14 formed in this way has an open end on one side. Figure 1 (As shown in the location of the sealing unit 16), after removing the initial support module, another expandable and contractible support module (e.g., slightly smaller in size than the initial support module) can be fitted onto the permeable membrane unit 15 in its first state. This module is then inserted into the roadway 14 through the opening. The other support module is then expanded to compress the permeable membrane unit 15 in its first state, completing the transition of the permeable membrane unit 15 from its first state to its second state. This firmly bonds and fixes the permeable membrane unit 15 to the roadway wall of the surrounding rock 3. Afterward, the expandable and contractible support module is removed by contraction, and the open end is sealed using the sealing unit 16. Subsequent compressed air injection / venting operations can then be performed, enabling a more convenient and accurate simulation of compressed air energy storage in abandoned coal mines. It is worth noting that because the permeable membrane unit 15 is equipped with multiple strain gauge units 13, the parameters collected by the strain gauge units 13 are closer to the strain parameters of the surrounding rock 3 at its roadway wall, thus providing a more accurate representation of the actual results. In addition, since the open end is sealed with a detachable sealing unit 16, the tunnel 14 of the simulation system can be opened and closed at any time as needed, which facilitates opening and inspection in case of abnormality and also makes it easier to clean the tunnel 14.

[0013] In a preferred embodiment, the strain gauge unit 13 is wirelessly connected to the information acquisition unit 10 (a wired connection is also possible, but since compression is required in this invention to bond the breathable membrane unit 15, a wireless connection reduces the impact on the wires). Each strain gauge unit 13 may include a data acquisition module, an MCU microprocessor, and a communication module, which transmits the acquired data to the information acquisition unit 10 through the communication module. The strain gauge units 13 are installed on the tunnel wall at designated locations as needed.

[0014] In a preferred embodiment, such as Figure 1 and Figure 2 As shown, the pressure plate unit 4 in this embodiment consists of a first pressure plate 41, a second pressure plate 42, a third pressure plate 43, and a fourth pressure plate 44. The first pressure plate 41, the second pressure plate 42, the third pressure plate 43, and the fourth pressure plate 44 are respectively arranged on the front, back, top, bottom, and four sides of the specimen box 2 (that is, no pressure plates are arranged on the left and right sides of the specimen box 2). The open end of the tunnel 14 is arranged on either the left or right side of the specimen box 2. Two of the first pressure plates 41, the second pressure plate 42, the third pressure plate 43, and the fourth pressure plate 44 that are arranged opposite each other are slidably located between the remaining two pressure plates (for example, the third pressure plate 43 and the fourth pressure plate 44 that are arranged opposite each other are slidably located between the first pressure plate 41 and the second pressure plate 42). With this arrangement, two of the opposite pressure plates can serve as main pressure plates, while the remaining two pressure plates can serve as auxiliary pressure plates, thereby facilitating the compression of the surrounding rock 3 of the tunnel in the specimen box 2 into a predetermined stratum condition before performing compressed air energy storage simulation. In addition, in this embodiment, pressure plates are not arranged on the left and right sides of the specimen box 2, mainly to reserve a space channel for sending the roadway surrounding rock 3, support module, etc. into the specimen box 2. Since pressure plates have been arranged on the front, back, top, bottom and bottom four sides, under the constraint of the specimen box 2 itself, it can be ensured that the roadway surrounding rock 3 is formed into the predetermined stratum condition.

[0015] To better achieve the objectives of this invention, in this embodiment, the breathable membrane unit 15 in the first state includes a protective layer 151, an adhesive layer 152, and a micro-breathable layer 153. The protective layer 151, adhesive layer 152, and micro-breathable layer 153 are all material layers with flow gaps (e.g., sponge-like material layers). The adhesive layer 152 is located between the protective layer 151 and the micro-breathable layer 153. From the micro-breathable layer 153 towards the protective layer 151, the flow gaps of the micro-breathable layer 153, adhesive layer 152, and protective layer 151 increase in a stepped manner to facilitate the diffusion of the adhesive liquid in the adhesive layer 152 towards the protective layer 151. The flow gaps on the micro-breathable layer 153 allow the adhesive liquid in the adhesive layer 152 to diffuse towards the protective layer 151. The adhesive layer 152 contains epoxy resin microcapsules distributed in a roughly uniform (not absolutely uniform) manner. The epoxy resin microcapsules are filled with epoxy resin liquid and can be broken when subjected to a predetermined pressure, causing the epoxy resin liquid inside to be released. This achieves the transformation of the permeable membrane unit 15 from the first state to the second state. When the permeable membrane unit 15 is placed in the tunnel 14, the protective layer 151 is located on the side closer to the surrounding rock 3 of the tunnel, and the micro-permeable layer 153 is located on the side closer to the tunnel 14. With the above settings, when the permeable membrane unit 15 in the first state is sent into the roadway 14, it can be expanded using the other support module mentioned above, so as to squeeze the permeable membrane unit 15 in the first state. At this time, the epoxy resin microcapsules in the permeable membrane unit 15 in the first state are destroyed, and the adhesive is released. Due to the different flow gaps of the protective layer 151, adhesive layer 152 and micro-permeable layer 153, the released adhesive will diffuse toward the protective layer 151 under the action of extrusion force, and further seep outward to contact the roadway wall of the surrounding rock 3, thereby achieving adhesion and completing the transformation of the permeable membrane unit 15 from the first state to the second state.

[0016] Preferably, the epoxy resin microcapsule includes at least a first chamber and a second chamber spaced apart from each other. The first chamber contains epoxy resin liquid A, and the second chamber contains epoxy resin liquid B. When the first chamber and the second chamber of the epoxy resin microcapsule are both destroyed due to extrusion pressure, the A and B adhesive liquids can be mixed to achieve curing and bonding.

[0017] It should be noted that in this embodiment, since the epoxy resin microcapsules need to be broken and release the adhesive when they are squeezed, collisions are likely to occur when the breathable membrane unit 15 is sent into the tunnel 14 using the other support module mentioned above. This can cause the adhesive to be released prematurely, affecting the bonding effect. Therefore, a protective layer 151 is provided in this embodiment to buffer and protect against premature release of the adhesive, thereby reducing the risk of affecting the bonding effect.

[0018] To better achieve the objectives of this invention, the strain gauge unit 13 is preferably disposed between the adhesive layer 152 and the micro-permeable layer 153. The advantage of this arrangement is that when the permeable membrane unit 15 is introduced into the roadway 14 using the aforementioned additional support module, the strain gauge unit 13 is protected, avoiding collision damage. When compressed using the aforementioned additional support module, the strain gauge unit 13 is also buffered and protected by the protective layer 151, the adhesive layer 152, and the micro-permeable layer 153. After the adhesive has cured, the adhesive layer 152 solidifies, similar to the hard front end of the roadway wall, and better reflects the stress deformation of the roadway surface. In addition, the micro-permeable layer 153 serves two purposes: firstly, it prevents the adhesive from seeping out, making it easier to remove the other support modules after shrinking them; secondly, since the outermost layer of the tunnel itself has a certain degree of porosity, the micro-permeable layer more closely approximates the actual geological conditions. Furthermore, as the adhesive seeps towards the tunnel wall and comes into contact with it, the soil and rock of the tunnel wall can absorb the moisture from the adhesive, allowing it to solidify quickly. However, on the side away from the tunnel wall, the soil and rock cannot absorb moisture, but the micro-permeable layer 153 can help to reduce moisture loss and improve the curing efficiency of the adhesive.

[0019] Additionally, it should be noted that in this embodiment, the inlet pipe 7 and outlet pipe 11 extend downwards to one end of the tunnel 14, which is basically flush with the tunnel wall above the tunnel 14. This arrangement is intended to reduce the difficulty of inserting the permeable membrane unit 15. Furthermore, after the permeable membrane unit 15 is inserted and bonded, it essentially seals the bottom ends of the inlet pipe 7 and outlet pipe 11. To simulate the compressed air energy storage waste tunnel, corresponding channels need to be opened on the permeable membrane unit 15 at the bottom ends of the inlet pipe 7 and outlet pipe 11 to connect the inlet pipe 7 and outlet pipe 11 to the tunnel 14.

[0020] In a preferred embodiment, pressure gauges 8 and valves 9 are respectively installed on the pipelines between the air inlet pipe 7 and the air outlet pipe 11 and the corresponding air injection unit 6 and power generation unit 12.

[0021] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0022] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to the embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A compressed air energy storage waste roadway simulation system, comprising a constant temperature chamber (1), a specimen box (2), roadway surrounding rock (3), a pressure plate unit (4), a pressure head (5), an air injection unit (6), an air inlet pipe (7), an information acquisition unit (10), an air outlet pipe (11), a power generation unit (12), a strain gauge unit (13), a breathable membrane unit (15), and a sealing unit (16), characterized in that, The specimen box (2) is set inside the constant temperature chamber (1). The specimen box (2) is filled with surrounding rock (3) of the tunnel and a tunnel (14) is formed in the middle of it. The specimen box (2) is also equipped with a pressure plate unit (4), which can compress the surrounding rock (3) of the tunnel (2) in the direction of the tunnel (14) under the action of the pressure head (5) on the specimen box (2). The top of the specimen box (2) is fixedly equipped with a spaced-apart air inlet pipe (7) and an air outlet pipe (11) in the vertical direction. One end of the air inlet pipe (7) and the air outlet pipe (11) extends downward to the tunnel (14), and the other end of the air inlet pipe (7) and the air outlet pipe (11) extends upward to the outside of the constant temperature chamber (1). The air inlet pipe (7) and the air outlet pipe (11) extending to the outside of the constant temperature chamber (1) are connected to the gas injection unit (6) and the power generation unit (12) respectively. One side of the tunnel (14) is At the open end, a sealing unit (16) is detachably provided to close the tunnel (14). The constant temperature chamber (1) and the specimen box (2) are both provided with openings that match the open end. A breathable membrane unit (15) is bonded and fixed on the tunnel wall of the surrounding rock (3) near the tunnel (14). Multiple strain gauge units (13) are provided on the breathable membrane unit (15). Each strain gauge unit (13) is connected to the information acquisition unit (10). The breathable membrane unit (15) is in a first state before being bonded to the tunnel wall. The breathable membrane unit (15) is in a second state after being bonded to the tunnel wall. In the first state, the adhesive in the breathable membrane unit (15) does not seep out. In the second state, the breathable membrane unit (15) uses the adhesive in it to seep out to the tunnel wall to achieve solidification and bonding with the surrounding rock (3). The breathable membrane unit (15) in its first state includes a protective layer (151), an adhesive layer (152), and a micro-permeable layer (153). The protective layer (151), adhesive layer (152), and micro-permeable layer (153) are all material layers with flow gaps. The adhesive layer (152) is located between the protective layer (151) and the micro-permeable layer (153). From the micro-permeable layer (153) towards the protective layer (151), the flow gaps of the micro-permeable layer (153), adhesive layer (152), and protective layer (151) increase in a stepped manner to facilitate the diffusion of the adhesive liquid in the adhesive layer (152) towards the protective layer (151). The flow gaps on the layer (153) prevent the adhesive liquid of the adhesive layer (152) from seeping and spreading into the micro-permeable layer (153). The adhesive layer (152) contains epoxy resin microcapsules in a uniform distribution. The epoxy resin microcapsules are filled with epoxy resin liquid, which can be broken when subjected to a predetermined pressure and cause the epoxy resin liquid inside to be released, thereby realizing the transformation of the permeable membrane unit (15) from the first state to the second state. When the permeable membrane unit (15) is placed in the roadway (14), the protective layer (151) is located on the side closer to the roadway surrounding rock (3), and the micro-permeable layer (153) is located on the side closer to the roadway (14). The strain gauge unit (13) is placed between the adhesive layer (152) and the micro-permeable layer (153); the permeable membrane unit (15) is fixed to the roadway wall of the surrounding rock (3) by adhesive bonding.

2. The compressed air energy storage waste roadway simulation system as described in claim 1, characterized in that, The epoxy resin microcapsule includes at least a first chamber and a second chamber spaced apart from each other. The first chamber contains epoxy resin liquid A, and the second chamber contains epoxy resin liquid B. When the first chamber and the second chamber of the epoxy resin microcapsule are both destroyed due to extrusion pressure, the A and B adhesive liquids can be mixed to achieve curing and bonding.

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