Gas storage reservoir test method based on structural parameters of gas storage reservoir

Abstract

The present invention discloses a method for testing a gas storage reservoir based on the structural parameters of the gas storage reservoir, which relates to the technical field of energy storage. The present invention includes a stress loading device, a thermal loading device, an acoustic emission monitoring device, and a distributed optical fiber device. A containing cavity for containing a gas storage reservoir model is provided in the stress loading device to apply stress to the gas storage reservoir model. The thermal loading device is in liquid circuit communication with the gas storage cavity of the gas storage reservoir model to adjust the pressure and temperature in the gas storage cavity. The acoustic emission monitoring device is embedded in the stress loading device to monitor the rupture data of the gas storage reservoir model. The distributed optical fiber device is embedded in the gas storage cavity to monitor the temperature data and deformation data of the gas storage reservoir model. Thus, the operation test of the gas storage reservoir model under different working conditions can be carried out, and the structural stability of the gas storage reservoir model under different operating conditions can be monitored. It can provide data reference for the design of the gas storage reservoir and reduce the design difficulty of the structural parameters of the gas storage reservoir.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage, and particularly to a method for testing a gas storage reservoir based on the structural parameters of the gas storage reservoir. Background Art

[0002] Compressed Air Energy Storage (CAES) power stations are a large-scale energy storage technology that uses electricity to compress air and store it in underground gas storage reservoirs, and then releases the compressed air when needed to generate electricity through a turbine. CAES technology is suitable for balancing the power grid load and storing intermittent electricity generated by renewable energy sources (such as wind and solar energy), thereby improving the stability of the power grid.

[0003] However, during the popularization process of compressed air energy storage power stations, due to the lack of a completed gas storage reservoir project for reference in actual applications, the design and construction difficulty of gas storage reservoirs in different regions has been greatly increased. Summary of the Invention

[0004] In view of the above problems, the present invention is proposed to provide a method for testing a gas storage reservoir based on the structural parameters of the gas storage reservoir that overcomes or at least partially solves the above problems.

[0005] Based on the first aspect of the present invention, there is also provided a method for testing a gas storage reservoir based on the structural parameters of the gas storage reservoir. The test method is based on a gas storage reservoir test system, and the test system includes:

[0006] A stress loading device, in which a containing cavity for containing a gas storage reservoir model is provided to apply stress to the gas storage reservoir model. The gas storage reservoir model is obtained by manufacturing a corresponding three-dimensional geological model according to the structural parameters of the gas storage reservoir;

[0007] A thermal loading device, which is in liquid communication with the gas storage cavity of the gas storage reservoir model to adjust the pressure and temperature of the hydraulic oil in the gas storage cavity;

[0008] An acoustic emission monitoring device, which is embedded in the stress loading device to monitor the rupture data of the gas storage reservoir model;

[0009] A distributed optical fiber device, which is embedded in the gas storage cavity and arranged around the inner wall of the gas storage cavity to monitor the temperature data and deformation data of the gas storage reservoir model;

[0010] The test method includes:

[0011] Determine the in-situ stress based on the geological data of the gas storage reservoir associated with the gas storage reservoir model, where the gas storage reservoir model is obtained by manufacturing a corresponding three-dimensional geological model according to the structural parameters of the gas storage reservoir;

[0012] Adjust the stress loading device to apply the in-situ stress to the gas storage reservoir model to simulate the stress-bearing environment of the gas storage reservoir;

[0013] According to the structural data of the gas storage reservoir and the thermodynamic relationship associated with compressed air, determine the temperature change sequence of the air in the gas storage reservoir at a preset injection and production rate within a cyclic operation period, where the cyclic operation period includes an air injection stage, a first gas storage stage, a gas extraction stage, and a second gas storage stage, and the temperature change sequence is used to characterize the change of the air temperature value within a cyclic operation period. The gas temperature of the gas storage reservoir is calculated according to the following formula:

[0014] ;

[0015] T refers to the gas temperature; refers to the temperature at the start time of the nth stage ; t is the calculation time in seconds; refers to the temperature value that changes with time within the current operation stage; refers to the reciprocal of the operation duration within the current operation stage; the 0th stage is the air injection stage; the first stage is the first gas storage stage; the second stage is the gas extraction stage; the third stage is the second gas storage stage;

[0016] And based on the temperature change sequence, determine the pressure change sequence of the air in the gas storage reservoir at a preset injection and production rate within a cyclic operation period, and the pressure change sequence is used to characterize the change of the air pressure value within a cyclic operation period;

[0017] Adjust the thermal loading device according to the pressure change sequence and the temperature change sequence to test the operation condition data of the gas storage reservoir, where the operation condition data at least includes fracture data, temperature data, and deformation data.

[0018] An optional aspect of the invention, the geological data at least includes the following geological parameters: thermal conductivity, thermal expansion coefficient, and external load.

[0019] An optional aspect of the invention, the test method further includes a model manufacturing step of the gas storage reservoir model, and the model manufacturing step includes:

[0020] Obtain the geological data and structural parameters of the gas storage reservoir;

[0021] Pour the gas storage reservoir model according to the geological data and structural parameters.

[0022] An optional invention content is that the geological similarity between the geological data of the gas storage reservoir model obtained by pouring and the geological data of the gas storage reservoir is greater than or equal to the first similarity threshold.

[0023] An optional invention content is that the test method further includes:

[0024] Updating the pressure change sequence and the temperature change sequence based on different injection and production rates;

[0025] According to the updated pressure change sequence and temperature change sequence, adjusting the thermal loading device to perform temperature adjustment and pressure adjustment on the gas storage reservoir model, so as to test the operating condition data of the gas storage reservoir under different injection and production rates.

[0026] An optional invention content is that the test method further includes:

[0027] After each update of the pressure change sequence and the temperature change sequence, replacing the gas storage reservoir model.

[0028] An optional invention content is that after replacing the gas storage reservoir model, the test method further includes:

[0029] According to the updated pressure change sequence and temperature change sequence, adjusting the thermal loading device to perform temperature adjustment and pressure adjustment on the replaced gas storage reservoir model, so as to test the operating condition data of gas storage reservoirs with different structural parameters under different injection and production rates.

[0030] Compared with the prior art, the present invention includes a stress loading device, a thermal loading device, an acoustic emission monitoring device, and a distributed optical fiber device. A receiving cavity for receiving the gas storage reservoir model is provided in the stress loading device to apply stress to the gas storage reservoir model. The thermal loading device is in fluid communication with the gas storage cavity of the gas storage reservoir model to adjust the pressure and temperature of the hydraulic oil in the gas storage cavity. The acoustic emission monitoring device is embedded in the stress loading device to monitor the fracture data of the gas storage reservoir model. And the distributed optical fiber device is embedded in the gas storage cavity and arranged around the inner wall of the gas storage cavity to monitor the temperature data and deformation data of the gas storage reservoir model. Thus, corresponding stress, temperature, and pressure can be applied to the gas storage reservoir model to conduct operating tests of the gas storage reservoir model under different working conditions, and based on the fracture data, temperature data, and deformation data, the structural stability of the gas storage reservoir model under different operating conditions can be monitored. Moreover, the operating safety of gas storage reservoirs with different structural parameters can be tested, which can provide data reference for the later design of gas storage reservoirs and reduce the design difficulty of gas storage reservoir structural parameters.

[0031] The above description is only an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention, it can be implemented according to the content of the specification. Moreover, in order to make the above and other objects, features and advantages of the present invention more obvious and understandable, the specific embodiments of the present invention are hereinafter given. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] By reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present invention. Moreover, throughout the drawings, the same reference numerals are used to represent the same components.

[0033] In the drawings:

[0034] Figure 1 is a schematic structural diagram of a gas storage reservoir test system based on the structural parameters of the gas storage reservoir provided by an embodiment of the present invention;

[0035] Figure 2 is a partial schematic structural diagram of a gas storage reservoir test system based on the structural parameters of the gas storage reservoir provided by an embodiment of the present invention;

[0036] Figure 3 is a schematic structural diagram of the connection structure between an acoustic emission sensor and a loading plate provided by an embodiment of the present invention;

[0037] Figure 4 is a schematic flow chart of the steps of a gas storage reservoir test method based on the structural parameters of the gas storage reservoir provided by an embodiment of the present invention;

[0038] Reference numerals: 1, stress loading device; 11, loading plate; 1101, groove; 1102, liquid inlet hole; 1103, liquid outlet hole; 12, stress loading component; 2, acoustic emission sensor; 3, thermal loading device; 31, liquid pipeline; 4, distributed optical fiber sensor; 5, gas storage reservoir model; 501, gas storage cavity. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] The exemplary embodiments of the present invention will be described in more detail below with reference to the drawings. Although the exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided so that the present invention can be more thoroughly understood and the scope of the present invention can be completely conveyed to those skilled in the art.

[0040] Compressed Air Energy Storage (CAES) is a large-scale energy storage technology that uses electricity to compress air and store it in underground gas storage caverns. When needed, the compressed air is released and used to generate electricity through a turbine. CAES technology is suitable for balancing the power grid load and storing intermittent electricity generated by renewable energy sources such as wind and solar energy, thereby improving the stability of the power grid.

[0041] However, during the popularization process of compressed air energy storage power stations, due to the lack of completed gas storage cavern projects for reference in actual applications, the design and construction difficulty of gas storage caverns in different regions has increased significantly.

[0042] Based on the above technical problems, the embodiments of the present invention are proposed. The embodiments of the present invention may include a stress loading device 1, a thermal loading device 3, an acoustic emission monitoring device, and a distributed optical fiber device. A containing cavity for containing a gas storage cavern model 5 is provided in the stress loading device 1 to apply stress to the gas storage cavern model 5. The thermal loading device 3 is in liquid communication with the gas storage cavity 501 of the gas storage cavern model 5 to adjust the pressure and temperature of the hydraulic oil in the gas storage cavity 501. The acoustic emission monitoring device is embedded in the stress loading device 1 to monitor the fracture data of the gas storage cavern model 5. And the distributed optical fiber device is embedded in the gas storage cavity 501 and arranged around the inner wall of the gas storage cavity 501 to monitor the temperature data and deformation data of the gas storage cavern model 5. Thus, corresponding stress, temperature, and pressure can be applied to the gas storage cavern model 5 to conduct operation tests of the gas storage cavern model 5 under different working conditions, and based on the fracture data, temperature data, and deformation data, the structural stability of the gas storage cavern model 5 under different operating conditions can be monitored. Thereby, data reference can be provided for the design of the gas storage cavern in the later stage, and the design and construction difficulty of the gas storage cavern can be reduced.

[0043] The embodiments of the present invention can be applied to the design stage of the gas storage cavern. Corresponding stress, temperature, and pressure are applied to the gas storage cavern model 5 to conduct operation tests of the gas storage cavern model 5 under different working conditions, and based on the fracture data, temperature data, and deformation data, the structural stability of the gas storage cavern model 5 under different operating conditions can be monitored. Thereby, data reference can be provided for the design of the gas storage cavern in the later stage.

[0044] In addition, the embodiments of the present invention can also be applied to the maintenance stage of the gas storage cavern, that is, after it is put into use, operation tests of the gas storage cavern model 5 can be carried out according to the relevant operation parameters of the surrounding rock of the gas storage cavern, so that the current operation condition of the surrounding rock can be predicted based on the monitored fracture data, temperature data, and deformation data, and thus it is convenient to carry out the maintenance of the gas storage cavern according to the predicted current operation condition.

[0045] Reference Figures 1-3 According to Figures 1-3 , an embodiment of the present invention provides a gas storage reservoir test system based on the structural parameters of a gas storage reservoir. The test system may include a stress loading device 1, a thermal loading device 3, an acoustic emission monitoring device, and a distributed optical fiber device, where:

[0046] A receiving cavity for receiving a gas storage reservoir model 5 is provided in the stress loading device 1 to apply stress to the gas storage reservoir model 5. The thermal loading device 3 is in liquid communication with the gas storage cavity 501 of the gas storage reservoir model 5 to adjust the pressure and temperature of the hydraulic oil in the gas storage cavity 501. The acoustic emission monitoring device is embedded in the stress loading device 1 to monitor the fracture data of the gas storage reservoir model 5. And the distributed optical fiber device is embedded in the gas storage cavity 501 and disposed around the inner wall of the gas storage cavity 501 to monitor the temperature data and deformation data of the gas storage reservoir model 5.

[0047] In an embodiment of the present invention, the geological parameters of the gas storage reservoir model 5 are associated with the geological parameters of the underground surrounding rock, that is, the geological similarity is greater than or equal to a first similarity threshold. The surrounding rock refers to the rock around the underground gas storage reservoir. The first similarity threshold may be values such as 90%, 95%, and 97%. Those skilled in the art can determine the specific first similarity threshold according to the actual test results and will not be further limited here. Among them, the geological parameters at least include thermal conductivity, thermal expansion coefficient, and external stress (which can also be called external load), etc. Under the condition of ensuring geological similarity, according to the structural parameters of the gas storage reservoir. For example, the structural parameters of the gas storage reservoir may include, but are not limited to, the lining radius, lining thickness, stress resistance strength, etc. of the gas storage reservoir. A gas storage reservoir model 5 having a gas storage cavity 501 is formed by pouring a variety of materials such as water, sand, lime, cement, and concrete. That is to say, the gas storage reservoir model is obtained by manufacturing a corresponding three-dimensional geological model according to the structural parameters of the gas storage reservoir. In some examples, the gas storage reservoir model 5 may be a hexahedron. In other examples, the gas storage reservoir model 5 may be a cube with dimensions of 100 cm × 100 cm × 100 cm, and the circumferential cross-section of the gas storage cavity 501 may be circular.

[0048] The stress loading device 1 is used to apply stress to the gas storage reservoir model 5, that is, to simulate the external stress received by the underground surrounding rock when excavating the gas storage reservoir. Thus, through the stress loading device 1, the same stress as the external stress received by the underground surrounding rock can be applied to the gas storage reservoir model 5. Thereby, the stress-bearing environment of the underground gas storage reservoir can be simulated, and the ground stress received by the gas storage reservoir in the actual underground environment can be simulated. Among them, the ground stress refers to the stress existing in the earth's crust, which includes the stress caused by the weight of the rock above the gas storage reservoir and the tectonic stress transmitted by the adjacent plots around the gas storage reservoir or the bottom of the gas storage reservoir.

[0049] The acoustic emission monitoring device is embedded in the stress loading device 1, and it uses the acoustic emission phenomenon to monitor the fracture data of the gas storage reservoir model 5. Among them, the fracture data may include, but is not limited to, data such as model deformation and fracture. The acoustic emission phenomenon refers to the phenomenon that when a solid material is subjected to a load exceeding its mechanical resistance capacity, its internal structure will undergo dislocation and fracture. This process is accompanied by the release of energy, so that the energy propagates in the solid medium in the form of mechanical waves from the damaged part to the surrounding environment.

[0050] The thermal loading device 3 is in liquid circuit communication with the gas storage cavity 501, and the pressure and temperature of the hydraulic oil in the gas storage cavity 501 are adjusted through the thermal loading device 3, so that according to the operating parameters of different compressed air energy storage power stations, the temperature and pressure of the hydraulic oil located in the gas storage cavity 501 can be changed, so as to form a complete simulation of the corresponding gas temperature and pressure change process during the gas injection and gas production processes of the gas storage reservoir. Among them, in some alternative embodiments, the thermal loading device 3 may be a hydraulic station with a temperature control system. Thus, during the test process, the temperature and pressure of the hydraulic oil can be controlled.

[0051] During the actual test process, control the stress loading device 1 to apply the external stress received by the surrounding rock associated with the gas storage reservoir model 5 to the gas storage reservoir model 5. Then, by repeatedly adjusting the temperature loading parameters and pressure loading parameters of the thermal loading device 3, monitor the fracture data of the gas storage reservoir model 5 through the acoustic emission monitoring device, and monitor the temperature data and deformation data of the gas storage reservoir through the distributed optical fiber device. Thus, based on the fracture data, temperature data and deformation data, the structural stability of the gas storage reservoir model 5 under different operating conditions can be monitored. It can provide data reference for the later design of the gas storage reservoir, reduce the design and construction difficulty of the gas storage reservoir, and improve the structural stability of the compressed air energy storage gas storage reservoir.

[0052] In an alternative embodiment of the invention, referring to Figure 1 , Figure 2 and Figure 3 as shown, the stress loading device 1 may include six loading plates 11 and a stress loading assembly 12. The six loading plates 11 cooperate to form the accommodating cavity. Among them, at least two of the loading plates 11 are provided with communication holes through which the liquid circuit pipes 31 of the thermal loading device 3 pass. The stress loading assembly 12 is fixedly connected to the end faces of the respective loading plates 11 away from the accommodating cavity, so as to push the loading plates 11 to move through the stress loading assembly 12 and adjust the stress applied to the gas storage reservoir.

[0053] In the embodiments of the present invention, the loading plate 11 is used to form pressure contact with the outer surface of the gas storage reservoir model 5 to simulate the in-situ stress received by the surrounding rock / gas storage reservoir. The six faces of the hexahedron-structured gas storage reservoir model 5 respectively form pressure contact with six loading plates 11. Among them, the end face of the loading plate 11 away from the gas storage reservoir model 5 is fixedly connected to the stress loading assembly 12. Thus, under the action of the stress loading assembly 12, the loading plate 11 is pushed to move closer to or away from the gas storage reservoir model 5. Thereby, the stress applied to the gas storage reservoir model 5 can be adjusted. By adjusting the pressing pressure of different loading plates 11 on the gas storage reservoir model 5, the in-situ stress received by the surrounding rock with different geological parameters can be simulated.

[0054] In some embodiments, for the convenience of placing and fixing the gas storage reservoir model 5, during the actual adjustment process, the position of the loading plate 11 at the bottom is fixed. Thus, the movements of the top loading plate 11 and the four-side loading plates 11 can be adjusted to achieve stress adjustment of the gas storage reservoir model 5.

[0055] In some embodiments, communication holes may be provided on the bottom loading plate 11, and the liquid path pipes 31 of the thermal loading device 3 pass through the communication holes. Thus, while the loading plate 11 forms pressure contact with the gas storage reservoir model 5, the gas storage cavity 501 of the gas storage reservoir model 5 can be ensured to be in liquid path communication with the outside. Among them, the communication holes may include a liquid inlet hole 1102 and a liquid outlet hole 1103. The liquid path pipes 31 may be rigid pipes. For example, the liquid path pipes 31 may be steel pipes, etc.

[0056] In some alternative embodiments, considering that the circumferential cross-section of the gas storage cavity 501 is usually circular, thus, the liquid path pipes 31 can be fixed on the two axial end faces of the gas storage cavity 501. And the liquid inlet hole 1102 and the liquid outlet hole 1103 are respectively provided on two relatively arranged loading plates 11. For example, the liquid inlet hole 1102 and the liquid outlet hole 1103 are respectively provided on two relatively arranged side loading plates 11. For another example, the liquid inlet hole 1102 and the liquid outlet hole 1103 are respectively provided on two relatively arranged top loading plates 11 and bottom loading plates 11.

[0057] Considering the adjustment convenience of the stress loading assembly 12, the liquid inlet hole 1102 and the liquid outlet hole 1103 can be respectively provided on the top loading plate 11 and the bottom loading plate 11. For example, the liquid inlet hole 1102 can be provided on the top loading plate 11, and the liquid outlet hole 1103 can be provided on the bottom loading plate 11. For another example, the liquid inlet hole 1102 can be provided on the bottom loading plate 11, and the liquid outlet hole 1103 can be provided on the top loading plate 11.

[0058] Considering the sealing performance of the gas storage cavity 501, the liquid pipeline 31 may include a joint pipeline, which may be fixed by pouring during the manufacturing process of the gas storage reservoir model 5. The joint pipeline and the communication hole are in clearance fit, so that when the gas storage reservoir model 5 is placed on the bottom loading plate 11, the position of the gas storage reservoir model 5 can be located through the joint pipeline, facilitating the stress adjustment of the stress loading component 12.

[0059] As an example of the stress loading component 12, the stress loading component 12 can be realized by opening threaded holes on a fixing plate, embedding connecting bolts into the threaded holes and threadedly connecting them with the fixing plate. The top of the connecting bolt forms a pressing contact with the loading plate 11, so that the stress applied by the loading plate 11 to the gas storage reservoir model 5 can be adjusted by screwing the connecting bolt. During the screwing process, a pressure sensor can be set at the top of the connecting bolt to detect the pressure applied to the loading plate 11 through the pressure sensor.

[0060] In an optional embodiment of the invention, refer to Figure 3 As shown, the acoustic emission monitoring device includes at least one acoustic emission sensor 2. At least one groove 1101 is opened on the end face of the loading plate 11 close to the accommodating cavity, and the acoustic emission sensor 2 is embedded in the groove 1101.

[0061] In the embodiment of the present invention, the acoustic emission monitoring device may include at least one acoustic emission sensor 2. The acoustic emission sensor 2 mainly converts the received mechanical vibration (also called mechanical wave or stress wave) in the gas storage reservoir model 5 into an electrical signal based on the piezoelectric effect. Therefore, at least one groove 1101 can be opened on the end face of the loading plate 11 close to the accommodating cavity, and the number of the grooves 1101 can be adapted to the number of the acoustic emission sensors 2. Then, the acoustic emission sensors 2 are fixed by being embedded in the grooves 1101, and the sensing heads of the acoustic emission sensors 2 can be flush with the surface of the loading plate 11, so that when the loading plate 11 forms a pressing contact with the gas storage reservoir model 5, it is ensured that the acoustic emission sensors 2 form a pressing contact with the gas storage reservoir model 5, ensuring the detection accuracy of the acoustic emission sensors 2.

[0062] A wire hole communicating with the end face of the loading plate 11 far from the accommodating cavity can also be opened on the bottom wall of the groove 1101, facilitating the wiring of the acoustic emission sensors 2.

[0063] In an alternative embodiment of the invention, when there are at least two acoustic emission sensors 2, the at least two acoustic emission sensors 2 are spaced apart on the loading plate 11.

[0064] In the embodiment of the present invention, in order to improve the detection accuracy of the deformation data of the gas storage reservoir model 5, multiple acoustic emission sensors 2 can be provided. When there are at least two acoustic emission sensors 2, the at least two acoustic emission sensors 2 are spaced apart on the loading plate 11, so that the deformation data of the gas storage reservoir model 5 can be monitored from different angles.

[0065] For example, two acoustic emission sensors 2 are installed on the top loading plate 11, two acoustic emission sensors 2 are installed on the bottom loading plate 11, and three emission sensors are respectively installed on each side loading plate 11, etc. Those skilled in the art can also select the number of the acoustic emission sensors 2 according to the size specifications of the gas storage reservoir model 5, and no excessive limitation is made here.

[0066] In an alternative embodiment of the invention, the distributed optical fiber device includes a distributed optical fiber sensor 4, wherein the distributed optical fiber sensor 4 surrounds at least two circles of the inner wall of the gas storage cavity 501.

[0067] In the embodiment of the present invention, the distributed optical fiber sensor 4 utilizes the scattering phenomenon in the optical fiber and obtains the distribution information of physical parameters along the length direction of the optical fiber by detecting these scattered lights. Thus, through the distributed optical fiber sensor 4 embedded in the gas storage cavity 501, the temperature data and deformation data along the length direction of the optical fiber can be obtained.

[0068] In order to improve the detection accuracy of the temperature data and the detection accuracy of the deformation data, the distributed optical fiber sensor 4 in the gas storage cavity 501 needs to have a certain length. Preferably, the distributed optical fiber sensor 4 surrounds at least two circles of the inner wall of the gas storage cavity 501, so as to ensure that the amount of data detected in the circumferential direction of the gas storage cavity 501 is sufficient. When the distributed optical fiber sensor 4 is embedded in the inner wall of the gas storage cavity 501, it can be spirally wound around the inner wall of the gas storage cavity 501, and the distance between adjacent two circles of the distributed optical fiber sensor 4 can be kept the same everywhere. For example, the distance can be 10 cm, etc., and no excessive limitation is made here.

[0069] Both ends of the distributed optical fiber sensor 4 are respectively led out from the liquid outlet hole 1103 and the liquid inlet hole 1102, and corresponding optical fiber guide holes can be opened on the liquid cooling pipeline for the distributed optical fiber sensor 4 to pass through. Those skilled in the art can seal the optical fiber guide holes according to the actual scenario, and no excessive limitation is made here.

[0070] In summary, the embodiments of the present invention disclose a stress loading device 1, a thermal loading device 3, an acoustic emission monitoring device, and a distributed optical fiber device. A receiving cavity for receiving the gas storage reservoir model 5 is provided in the stress loading device 1 to apply stress to the gas storage reservoir model 5. The thermal loading device 3 is in liquid communication with the gas storage cavity 501 of the gas storage reservoir model 5 to adjust the pressure and temperature of the hydraulic oil in the gas storage cavity 501. The acoustic emission monitoring device is embedded in the stress loading device 1 to monitor the fracture data of the gas storage reservoir model 5. And the distributed optical fiber device is embedded in the gas storage cavity 501 and disposed around the inner wall of the gas storage cavity 501 to monitor the temperature data and deformation data of the gas storage reservoir model 5. Thus, corresponding stress, temperature, and pressure can be applied to the gas storage reservoir model 5 to conduct operation tests of the gas storage reservoir model 5 under different working conditions, and based on the fracture data, temperature data, and deformation data, the structural stability of the gas storage reservoir model 5 under different operating conditions can be monitored. Thereby, data reference can be provided for the design of the gas storage reservoir in the later stage, and the design and construction difficulty of the gas storage reservoir can be reduced.

[0071] Referring to Figure 4 , the embodiments of the present invention provide a gas storage reservoir test method based on the structural parameters of the gas storage reservoir. The test method may include:

[0072] S401. Determine the in-situ stress based on the geological data of the gas storage reservoir associated with the gas storage reservoir model 5.

[0073] S402. Adjust the stress loading device 1 to apply the in-situ stress to the gas storage reservoir model 5 to simulate the stress-bearing environment of the gas storage reservoir.

[0074] In the embodiments of the present invention, the test method further includes a model manufacturing step of the gas storage reservoir model 5. The model manufacturing step may further include obtaining the geological data and structural parameters of the gas storage reservoir, and then pouring the gas storage reservoir model 5 according to the geological data and structural parameters. Among them, the geological similarity between the geological data of the gas storage reservoir model 5 and the geological data of the gas storage reservoir is greater than or equal to the first similarity threshold. The first similarity threshold may be a condition for determining that the material for manufacturing the gas storage reservoir model 5 can replace the actual surrounding rock material. For example, the surrounding rock refers to the rock around the underground gas storage reservoir. The first similarity threshold may be values such as 90%, 95%, and 97%. Those skilled in the art can determine the specific first similarity threshold according to the actual test results and will not be limited too much here.

[0075] Thus, the geological parameters of the manufactured gas storage reservoir model 5 are associated with the geological parameters around the gas storage reservoir, that is, the geological similarity is greater than or equal to the first similarity threshold. Among them, the geological data at least includes the following geological parameters: thermal conductivity, coefficient of thermal expansion, and external stress (which can also be called external load), etc. Under the condition of ensuring geological similarity, according to the gas storage reservoir structure parameters, for example, the gas storage reservoir structure parameters can include but are not limited to the lining radius, lining thickness, stress resistance strength, etc. of the gas storage reservoir. A gas storage reservoir model 5 with a gas storage cavity 501 is formed by pouring a variety of materials such as water, sand, lime, cement, and concrete. That is to say, the gas storage reservoir model is obtained by manufacturing a corresponding three-dimensional geological model according to the gas storage reservoir structure parameters. In some examples, the gas storage reservoir model 5 can be a hexahedron. In other examples, the gas storage reservoir model 5 can be a cube with a size of 100 cm × 100 cm × 100 cm, and the circumferential cross-section of the gas storage cavity 501 can be circular.

[0076] In some optional embodiments of the invention, when comparing the geological similarity, the similarity mean value obtained by adding up the parameter similarities of each geological parameter and then taking the average can be used as the geological similarity.

[0077] The stress loading device 1 is used to apply stress to the gas storage reservoir model 5, that is, to simulate the external stress received by the underground surrounding rock of the excavated gas storage reservoir. Thus, through the stress loading device 1, the same stress as the external stress received by the underground surrounding rock can be applied to the gas storage reservoir model 5. Thereby, the stress-bearing environment of the underground gas storage reservoir can be simulated, and the ground stress received by the gas storage reservoir in the actual underground environment can be simulated. Among them, the ground stress refers to the stress existing in the earth's crust, which includes the stress caused by the weight of the rock above the gas storage reservoir and the tectonic stress transmitted by the adjacent plots around the gas storage reservoir or the bottom of the gas storage reservoir, etc.

[0078] S403. Determine the pressure change sequence and temperature change sequence of the air in the gas storage reservoir under the preset injection and production rate within a cyclic operation period.

[0079] S404. Adjust the thermal loading device 3 according to the pressure change sequence and temperature change sequence to test the operation condition data of the gas storage reservoir.

[0080] In the embodiments of the present invention, it is considered that the energy stored in the gas storage reservoir is the thermal energy and pressure potential energy of air. During the operation of the gas storage reservoir, the temperature and pressure of the gas in the gas storage reservoir continuously change and affect each other. Moreover, since a cycle working period of the gas storage reservoir sequentially includes an air injection stage, a gas storage stage, a gas extraction stage, and a gas storage stage according to time sequence. When the gas storage reservoir is in the air injection stage, gas injection compression will be carried out; when the gas storage reservoir is in the first gas storage stage, high-pressure gas will be stored; when the gas storage reservoir is in the gas extraction stage, high-pressure gas will be collected, that is, gas extraction power generation will be carried out; when the gas storage reservoir is in the second gas storage stage, low-pressure gas will be stored.

[0081] The preset injection and production efficiency includes the air injection rate and the gas extraction rate. During the large-scale heating and pressurization and cooling and depressurization processes of compressed air in the gas storage reservoir, with different heating and pressurization rates and cooling and depressurization rates, the temperature, external stress, and structural deformation of the structure of the gas storage reservoir will all change. This will have a certain impact on the stable operation of the gas storage reservoir. Thus, by calculating the pressure change sequence and temperature change sequence of the air in the gas storage reservoir under the preset injection and production efficiency, the temperature adjustment and pressure adjustment of the thermal loading device 3 can be used to simulate the air temperature change and air pressure change in the gas storage reservoir during an actual cycle working period according to time sequence. The pressure change sequence is used to characterize the change of the air pressure value during a cycle working period, and the temperature change sequence is used to characterize the change of the air temperature value during a cycle working period.

[0082] Therefore, through the thermal loading device 3, according to the pressure change sequence and temperature change sequence, the pressure and temperature of the hydraulic oil in the gas storage cavity 501 can be adjusted, and the operation condition data of the gas storage reservoir can be tested through the deformation monitoring of the gas storage reservoir model 5. The operation condition data may include rupture data, temperature data, and deformation data, and the operation condition data is detected by the acoustic emission sensor 2 and the distributed optical fiber sensor 4. Among them, the rupture data may include the number of cracks and the crack width of the gas storage reservoir, etc.

[0083] Thus, it can provide data reference for the later construction of the gas storage reservoir and the operation parameters setting of the compressed air energy storage power station, and reduce the design and construction difficulty of the gas storage reservoir.

[0084] In some alternative embodiments, according to the structural data of the gas storage reservoir and the thermodynamic relationship associated with compressed air, a pressure change sequence of the air in the gas storage reservoir at a preset injection and production rate within one cycle operation period can be determined. The structural data may include the volume of the gas storage reservoir, the leakage rate, and the surrounding rock temperature, etc. Considering that when constructing an underground gas storage reservoir manually, it is usually excavated under hard rock conditions. Thus, the volume of the gas storage reservoir can be a constant. And considering that the gas storage reservoir has good airtightness, the leakage rate during the normal gas storage process of the gas storage reservoir can be negligible. Thus, the thermodynamic control formula for the compressed air in the gas storage reservoir can be as follows:

[0085] Formula (1)

[0086] In the above formula (1), p is the gas pressure in the gas storage reservoir (Pa); V is the volume of the gas storage reservoir ( ); T is the temperature of the compressed air in the gas storage reservoir (K); ρ is the density of the compressed air in the gas storage reservoir ( ); is the specific heat at constant volume of air (J / (kg·K)); R is the air gas constant (J / (kg·K)); Z is the air compressibility factor; is the convective heat transfer rate (J / s); is the heat transfer coefficient between the air in the gas storage reservoir and the surrounding rock (W / ( )); is the surface area of the gas storage reservoir ( ); is the temperature of the surrounding rock (K); t is the calculation time (s); u is the internal energy of the gas in the gas storage reservoir (J); h is the enthalpy of the gas in the gas storage reservoir (J); is the enthalpy of the injected gas (J); , are the injection rate function and the production rate function respectively (kg / s).

[0087] And, for the expressions of the enthalpy and internal energy of the gas in the gas storage reservoir, the following replacement formulas can be used for replacement, and the replacement formulas are as follows:

[0088] Formula (2)

[0089] In the above formula (2), is the specific heat at constant pressure of air (J / (kg·K)); is the temperature of the injected air (K); is the initial temperature of the gas in the gas storage reservoir (K); is the initial density of the gas in the gas storage reservoir ( ).

[0090] In the embodiments of the present invention, in order to simplify the calculation, the temperature change of the surrounding rock can be not considered, and the gas density in the gas storage reservoir can be replaced by the average gas density during the calculation period. And assuming that air is an ideal gas, according to Formula (1) and Formula (2), when Z = 1, then ;

[0091] Meanwhile, assuming that the temperature of the surrounding rock remains unchanged and the gas injection efficiency and gas production rate of the gas storage reservoir are respectively a fixed value, then 、 do not change with time, that is 、 , and the simplified calculation formula for the gas density and gas temperature of the gas storage reservoir is obtained as follows:

[0092] Formula (3)

[0093] Formula (4)

[0094] Formula (5)

[0095] In the above Formulas (3), (4) and (5), when n = 1, it corresponds to the first gas storage stage; when n = 2, it corresponds to the gas release stage; when n = 3, it corresponds to the second gas storage stage; refers to the temperature at the start time of the nth stage For example, when n = 0, refers to the temperature at the start time of the gas filling stage For example, when n = 1, refers to the temperature at the start time of the first gas storage stage For example, when n = 2, refers to the temperature at the start time of the gas release stage For example, when n = 3, refers to the temperature at the start time of the second gas storage stage ; refers to the initial time of a cycle operation period (i.e., gas injection and production cycle), and is also the start time of the gas filling stage; refers to the end time of the gas filling stage in a cycle operation period, and is also the start time of the first gas storage stage in a cycle period; refers to the end time of the first gas storage stage in a cycle operation period, and is also the start time of the gas release stage in a cycle period; refers to the end time of the gas release stage in a cycle operation period, and is also the start time of the second gas storage stage in a cycle period; Refers to the end moment of a cyclic operation period (i.e., gas injection and production cycle), and also the end moment of the second gas storage stage in a cycle period. Refers to the average density of the gas in the gas storage reservoir during a cyclic operation period.

[0096] After obtaining the gas temperature using formulas (3), (4) and (5), the gas pressure in the gas storage reservoir can be calculated using formula (1). Thus, a pressure change sequence and a temperature change sequence under a preset injection and production rate within a cyclic operation period can be obtained.

[0097] In an alternative embodiment of the invention, the test method may further include updating the pressure change sequence and the temperature change sequence based on different injection and production rates. And according to the updated pressure change sequence and temperature change sequence, adjusting the thermal loading device 3 to perform temperature adjustment and pressure adjustment on the gas storage reservoir model 5, so as to test the operation condition data of the gas storage reservoir under different injection and production rates.

[0098] In the embodiment of the present invention, multiple rates can be set in advance for the injection and production rate, so that according to different injection and production rates, a pressure change sequence and a temperature change sequence of the air in the gas storage reservoir under different injection and production rates within a cyclic operation period can be obtained. Thus, the gas storage reservoir model 5 can be adjusted in terms of temperature and pressure according to the updated pressure change sequence and temperature change sequence. Thus, through data monitoring of the gas storage reservoir model 5, the operation condition data of the gas storage reservoir under different injection and production rates can be obtained. And according to the operation condition data under different injection and production rates, data reference can be provided for setting the operation parameters of the compressed air energy storage power station.

[0099] In some other embodiments, in order to improve the test accuracy of the operation condition data under different injection rates, the gas storage reservoir model 5 can be replaced after each update of the pressure change sequence and the temperature change sequence. Thus, the influence of the operation condition data obtained from the previous test on the test result of the current test can be avoided.

[0100] In summary, the embodiments of the present invention disclose a method for testing a gas storage reservoir based on the structural parameters of the gas storage reservoir. The testing method may include first determining the in-situ stress based on the geological data of the gas storage reservoir associated with the gas storage reservoir model 5, where the geological data at least includes the following geological parameters: thermal conductivity, coefficient of thermal expansion, and external load. Then, adjusting the stress loading device 1 to apply the in-situ stress to the gas storage reservoir model 5 to simulate the stress-bearing environment of the gas storage reservoir. Next, determining the pressure change sequence and temperature change sequence of the air in the gas storage reservoir under a preset injection and production rate within a cyclic operation period. Finally, adjusting the thermal loading device 3 according to the pressure change sequence and temperature change sequence to test the operation condition data of the gas storage reservoir, where the operation condition data at least includes fracture data, temperature data, and deformation data. Thus, the operation condition of the gas storage reservoir during the large-scale heating, pressurization, cooling, and depressurization of compressed air in the gas storage reservoir can be tested. Thereby, data reference can be provided for the design of the gas storage reservoir in the later stage, reducing the design and construction difficulty of the gas storage reservoir. And it can provide reference for the setting of the operation parameters of the compressed air energy storage power station.

[0101] In the embodiments of the present invention, after determining the operation condition data of the gas storage reservoir according to the corresponding embodiments of the above testing method, considering that the operation condition data includes the fracture data, temperature data, and deformation data of the gas storage reservoir, it is possible to determine whether to increase the thickness of the lining structure of the gas storage reservoir, or replace the tensile strength of the lining material of the gas storage reservoir, or reinforce the surrounding rock of the gas storage reservoir, etc. Thus, an optimization scheme for the structural parameters of the gas storage reservoir can be determined according to the operation condition data. The optimization scheme of the structural parameters of the gas storage reservoir can be an optimization scheme of the structural parameters determined based on the operation condition data as a data reference on the preliminary design scheme. Thereby, the operation stability of the compressed air energy storage power station can be further improved.

[0102] Each embodiment in this specification is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other.

[0103] It is easy for those skilled in the art to think that any combination application of the above various embodiments is feasible. Therefore, any combination of the above various embodiments is an implementation scheme of the present invention. However, due to space limitations, this specification does not elaborate on each of them one by one here.

[0104] In the specification provided here, a large number of specific details are described. However, it can be understood that the embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures, and technologies are not shown in detail so as not to obscure the understanding of this specification.

[0105] Similarly, it should be understood that, in order to streamline the present invention and assist in understanding one or more of the various inventive aspects, in the foregoing description of the exemplary embodiments of the present invention, various features of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof.

[0106] Furthermore, those skilled in the art will appreciate that, although some of the embodiments described herein include certain features included in other embodiments and not others, the combination of features of different embodiments is meant to be within the scope of the present invention and forms different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

Claims

1. A gas storage reservoir test method based on gas storage reservoir structural parameters, characterized in that: The test method is based on the gas storage test system, which includes: A stress loading device (1), wherein a housing cavity for housing a gas storage reservoir model (5) is provided in the stress loading device (1) for applying stress to the gas storage reservoir model (5), wherein the gas storage reservoir model (5) is obtained by manufacturing a corresponding three-dimensional geological model based on gas storage reservoir structural parameters; A thermal loading device (3), the thermal loading device (3) being in fluid communication with the gas storage cavity (501) of the gas storage reservoir model (5) and being used for adjusting the pressure and temperature of the hydraulic oil in the gas storage cavity (501); An acoustic emission monitoring device, which is embedded in the stress loading device (1) and is used to monitor the rupture data of the gas storage model (5); A distributed optical fiber device, which is embedded in the gas storage cavity (501) and arranged around the inner wall of the gas storage cavity (501) to monitor temperature data and deformation data of the gas storage reservoir model (5); The test methods include: Determine the ground stress based on the geological data of the gas storage reservoir associated with the gas storage reservoir model (5), the gas storage reservoir model (5) is obtained by manufacturing a corresponding three-dimensional geological model based on the structural parameters of the gas storage reservoir; Adjusting the stress loading device (1) to apply ground stress to the gas storage reservoir model (5) to simulate the stress bearing environment of the gas storage reservoir; According to the structural data of the gas storage and the thermodynamic relationship associated with compressed air, the temperature change sequence of the air in the gas storage at the preset injection and production rate within a cycle operation period is determined. The cycle operation period includes the inflation stage, the first gas storage stage, the deflation stage and the second gas storage stage. The temperature change sequence is used to characterize the change of the air temperature value within a cycle working period. The gas temperature of the gas storage is calculated according to the following formula: ； T refers to the gas temperature; Refers to the start time of the nth stage The temperature at time t is the calculation time in seconds; Refers to the temperature value that changes with time during the current operating stage; Refers to the countdown of the running time in the current running stage; the zeroth stage is the charging stage; the first stage is the first gas storage stage; the second stage is the deflation stage; the third stage is the second gas storage stage; Based on the temperature change sequence, the pressure change sequence of the air in the gas storage at a preset injection and production rate within a cycle operation period is determined. The pressure change sequence is used to characterize the change of the air pressure value within a cycle working period; According to the pressure change sequence and the temperature change sequence, the thermal loading device (3) is adjusted to test the operating condition data of the gas storage reservoir, and the operating condition data at least includes rupture data, temperature data and deformation data.

2. The gas storage reservoir test method based on gas storage reservoir structural parameters according to claim 1, characterized in that: The geological data at least include the following geological parameters: thermal conductivity, thermal expansion coefficient and external load.

3. The gas storage reservoir test method based on gas storage reservoir structural parameters according to claim 1, characterized in that: The test method further comprises a model manufacturing step of a gas storage reservoir model (5), wherein the model manufacturing step comprises: Obtain geological data and structural parameters of gas storage facilities; Based on geological data and structural parameters, a gas storage reservoir model (5) is cast.

4. The gas storage reservoir test method based on gas storage reservoir structural parameters according to claim 3, characterized in that: The geological similarity between the geological data of the gas storage model (5) obtained by casting and the geological data of the gas storage is greater than or equal to a first similarity threshold.

5. The gas storage reservoir test method based on gas storage reservoir structural parameters according to claim 1, characterized in that: The test methods also include: Based on different injection and production rates, update the pressure change sequence and temperature change sequence; According to the updated pressure change sequence and temperature change sequence, the thermal loading device (3) is adjusted to adjust the temperature and pressure of the gas storage reservoir model (5) so as to test the operating condition data of the gas storage reservoir at different injection and production rates.

6. The gas storage reservoir test method based on gas storage reservoir structural parameters according to claim 5, characterized in that: The test methods also include: After each update of the pressure change sequence and the temperature change sequence, the gas storage reservoir model (5) is replaced.

7. The gas storage reservoir test method based on gas storage reservoir structural parameters according to claim 6, characterized in that: After replacing the gas storage reservoir model (5), the test method further comprises: According to the updated pressure change sequence and temperature change sequence, the thermal loading device (3) is adjusted to adjust the temperature and pressure of the replaced gas storage reservoir model (5) so as to test the operating condition data of gas storage reservoirs with different structural parameters at different injection and production rates.

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