A method and system for determining the maximum injection and production rate of compressed air energy storage in a salt cavern

Abstract

The present application relates to compressed air energy storage technology field, especially in kind of salt cavern compressed air energy storage maximum injection and production rate determination method and system, the method comprises: obtaining the mechanical parameters of salt cavern and wellbore of target gas storage; according to the mechanical parameters, the maximum injection and production rate of the salt cavern is calculated;According to the mechanical parameters, the maximum injection and production rate of the wellbore is calculated;Based on the maximum injection and production rate of the salt cavern and the maximum injection and production rate of the wellbore, the maximum injection and production rate of the target gas storage is calculated.This application deeply analyzes the high frequency injection and production technology characteristics of salt cavern compressed air energy storage, comprehensively considers the safety of salt cavern and wellbore system in salt cavern compressed air energy storage system, and puts forward a more comprehensive maximum injection and production rate design method of salt cavern compressed air energy storage.The maximum injection and production rate design method is supported by perfect theoretical model, considers comprehensive factors, is simple to calculate, scientific and reasonable.

Description

Technical Field

[0001] This invention relates to the field of compressed air energy storage technology, and in particular to a method and system for determining the maximum injection and production rates of compressed air energy storage in salt caverns. Background Technology

[0002] Renewable and clean energy sources such as wind power and solar power are intermittent and uncertain, and large-scale grid connection will impact the safety and stable operation of the power grid. Energy storage devices have the ability to migrate power and energy over time, thus providing a new technical solution to the grid connection problem of large-scale wind power, solar power and other new energy generation. At the same time, large-scale energy storage technology can achieve peak shaving and valley filling of the power grid, enhancing the safety of power grid operation.

[0003] The basic principle of compressed air storage in salt caverns is to convert electrical energy into compressed air and inject it into underground salt caverns during off-peak electricity demand periods (such as at night), and then release the compressed air and convert it back into electrical energy during peak demand periods (such as during the day). Compressed air storage power generation systems can utilize various underground structures, including aquifers, salt caverns, and hard rock caverns. Salt rock, in particular, has a very low permeability (less than 10-20m³). 2 With its excellent creep behavior, it can ensure the airtightness of the storage cavity; its mechanical properties are relatively stable, it has the ability to self-repair damage, and it can adapt to changes in storage pressure (because the pressure will change periodically during use). Therefore, the application of compressed gas storage in underground salt caverns has been recognized worldwide and is receiving increasing attention.

[0004] In recent years, the demand and scale of compressed air storage (CASP) projects in salt caverns have been increasing year by year. In practice, it has been found that when gas is extracted at different rates, there are significant differences in cavity shrinkage, salt cavern stability, and wellbore load. High-intensity gas extraction may lead to mechanical instability and crack formation in salt caverns with poor stability, resulting in failure of the salt cavern's sealing and stability, and even its abandonment. Conversely, low gas extraction rates cannot fully utilize the rapid response advantage of CASP, significantly reducing power generation efficiency. Furthermore, long-term monitoring and simulation studies have shown that the gas extraction rate is one of the key factors affecting salt cavern volume shrinkage. Therefore, quantitatively designing the maximum gas extraction rate for CASP in salt caverns is an urgent technical task in the management of CASP.

[0005] However, existing technologies are mainly designed for salt cavern gas storage and only limit the maximum gas extraction rate based on cavity stability and volume shrinkage. This is not entirely applicable to compressed air energy storage with higher injection and extraction frequencies. Furthermore, existing technologies have not analyzed the design method for gas extraction rates in salt cavern compressed air energy storage from a comprehensive perspective of the salt cavern and tubing. Summary of the Invention

[0006] This invention aims to at least partially solve one of the technical problems in the aforementioned technologies, and to this end proposes a method for determining the maximum injection-production gas rate of salt cavern compressed air energy storage, comprising:

[0007] Obtain the mechanical parameters of the salt cavern and wellbore of the target gas storage facility;

[0008] Calculate the maximum gas injection and production rate of the salt cavern based on the mechanical parameters;

[0009] Calculate the maximum gas injection / production rate of the wellbore based on the mechanical parameters;

[0010] The maximum gas injection and production rate of the target gas storage facility is calculated based on the maximum gas injection and production rate of the salt cavern and the maximum gas injection and production rate of the wellbore.

[0011] Furthermore, the mechanical parameters include: salt cavern mechanical parameters, wellbore mechanical parameters, and salt cavern surrounding rock mechanical parameters; wherein,

[0012] The mechanical parameters of the salt cavern include: the radius of the salt cavern at different depths;

[0013] The wellbore mechanical parameters include: the inner and outer diameters of the gas production tubing and the inner and outer diameters of the casing;

[0014] The mechanical parameters of the surrounding rock of the salt cavern include: elastic modulus, Poisson's ratio, shear strength, internal friction angle, and cohesion of the surrounding rock.

[0015] Further, calculating the maximum gas injection and production rate of the salt cavern based on the aforementioned mechanical parameters includes:

[0016] A mechanical model of the salt cavern is constructed based on the aforementioned mechanical parameters;

[0017] The deformation data of the salt cavern cavity and the surrounding rock are calculated using the mechanical model. The deformation data of the salt cavern cavity includes the volume shrinkage rate of the salt cavern cavity. The deformation data of the surrounding rock includes the maximum depth of plastic deformation of the surrounding rock.

[0018] The maximum gas injection and production rate of the salt cavern is calculated based on the deformation data.

[0019] Further, the maximum gas injection and production rate of the salt cavern is calculated based on the mechanical model, including: using a first preset value of the volume shrinkage rate of the salt cavern cavity and a second preset value of the maximum depth of plastic deformation of the surrounding rock being less than a second preset value as boundary conditions, to calculate the maximum gas injection and production rate of the salt cavern.

[0020] Furthermore, the volume shrinkage rate of the salt cavern cavity is calculated using the aforementioned mechanical model, and the formulas used include:

[0021]

[0022] Where E represents the volume shrinkage rate of the salt cavern cavity; Q E This indicates the gas extraction rate that satisfies the cavity contraction condition; ΔV represents the volume shrinkage rate of the salt cavern cavity under the gas extraction rate that satisfies the cavity shrinkage condition; ΔV represents the volume change of the cavity; V represents the initial volume of the cavity.

[0023] Furthermore, the maximum depth of plastic deformation of the surrounding rock of the salt cavern is calculated using the aforementioned mechanical model, and the formulas used include:

[0024]

[0025] Where σ1 represents the maximum principal stress; σ3 represents the minimum principal stress; c represents the cohesion of the rock; and φ represents the internal friction angle of the rock.

[0026] Furthermore, the maximum gas injection and production rate of the wellbore is calculated based on the mechanical parameters, including: taking the maximum gas production of the salt cavern being less than the wellhead erosion flow rate and the water vapor mass concentration in the wellbore being greater than the critical saturated water vapor mass concentration as boundary conditions, and calculating the maximum gas injection and production rate of the wellbore.

[0027] Furthermore, the calculation formula for the wellhead erosion flow rate includes:

[0028]

[0029] Among them, Q S denoted by erosion flow rate; C is an empirical constant; D represents the inner diameter of the gas sampling tubing; p represents the gas pressure inside the tubing; r represents the relative density of the gas; Z represents the compressibility factor of the gas; and T represents the gas temperature.

[0030] Furthermore, the calculation formula for the water vapor mass concentration in the wellbore includes:

[0031]

[0032] Among them, W w P represents the mass concentration of water vapor in the wellbore. sw denoted by saturated vapor pressure of water; p represents gas pressure inside the tube; T represents gas temperature; x1, x2, x3, x4, x5, x6, x7 are empirical constants.

[0033] Furthermore, the calculation formula for the gas temperature T includes:

[0034]

[0035] Where A represents the cross-sectional area of ​​the gas injection string; ρ represents the gas density; C v,gThe constant-pressure specific heat of the gas is represented by μ; t represents the running time; μ represents the specific heat of the gas at constant pressure. jT The Joule-Thomson coefficient represents the gas flow rate; v represents the gas velocity; z represents the depth; g represents the gravitational acceleration; and Qe represents the heat absorbed by the gas from the environment.

[0036] Further, based on the maximum gas injection and production rate of the salt cavern and the maximum gas injection and production rate of the wellbore, the maximum gas injection and production rate of the target gas storage is calculated, including:

[0037] The minimum value between the maximum gas injection / production rate of the salt cavern and the maximum gas injection / production rate of the wellbore is taken as the maximum gas injection / production rate of the target gas storage.

[0038] This application also proposes a system for determining the maximum injection-production rate of compressed air energy storage in salt caverns, comprising:

[0039] The parameter acquisition module is used to acquire the mechanical parameters of the salt cavern and wellbore of the target gas storage facility;

[0040] The first calculation module is used to calculate the maximum gas injection and production rate of the salt cavern based on the mechanical parameters.

[0041] The second calculation module is used to calculate the maximum gas injection and production rate of the wellbore based on the mechanical parameters.

[0042] The third calculation module is used to calculate the maximum gas injection rate of the target gas storage facility based on the maximum gas injection and production rate of the salt cavern and the maximum gas injection and production rate of the wellbore.

[0043] Furthermore, the method executed by the first computing module includes:

[0044] A mechanical model of the salt cavern is constructed based on the aforementioned mechanical parameters;

[0045] The deformation data of the salt cavern cavity and the surrounding rock are calculated using the mechanical model. The deformation data of the salt cavern cavity includes the volume shrinkage rate of the salt cavern cavity. The deformation data of the surrounding rock includes the maximum depth of plastic deformation of the surrounding rock.

[0046] The maximum gas injection and production rate of the salt cavern is calculated based on the deformation data.

[0047] Furthermore, the method executed by the second computing module includes:

[0048] Using the boundary conditions that the maximum gas production rate of the salt cavern is less than the wellhead erosion flow rate and the water vapor mass concentration in the wellbore is greater than the critical saturated water vapor mass concentration, the maximum gas injection and production rate of the wellbore is calculated.

[0049] Furthermore, the method executed by the third computing module includes:

[0050] The minimum value between the maximum gas injection / production rate of the salt cavern and the maximum gas injection / production rate of the wellbore is taken as the maximum gas injection / production rate of the target gas storage.

[0051] Compared with the prior art, the beneficial effects of the present invention are:

[0052] This application overcomes the limitations of designing the maximum gas production rate solely based on cavity stability. It deeply analyzes the characteristics of high-frequency injection and production technology in salt cavern compressed air energy storage, and comprehensively considers the safety of both the salt cavern and wellbore systems in the salt cavern compressed air energy storage system. A more comprehensive maximum gas production rate design method is proposed. Supported by a sound theoretical model, this method considers all factors, is computationally simple, and is scientifically sound.

[0053] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention can be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings. The technical solutions of the invention will be further described below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0054] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0055] Figure 1 This is a schematic diagram illustrating the method for determining the maximum gas injection and production rate of compressed air energy storage in salt caverns, as given in the example.

[0056] Figure 2 This is a schematic diagram of a system for determining the maximum gas injection and production rate of compressed air energy storage in salt caverns, as shown in the example. Detailed Implementation

[0057] The present invention will be described below with reference to the accompanying drawings. The preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0058] The method for determining the maximum gas injection and production rate of salt cavern compressed air energy storage proposed in this application includes:

[0059] Obtain the mechanical parameters of the salt cavern and wellbore of the target gas storage facility;

[0060] Calculate the maximum gas injection and production rate of the salt cavern based on the aforementioned mechanical parameters;

[0061] Calculate the maximum gas injection / production rate of the wellbore based on the aforementioned mechanical parameters;

[0062] The maximum gas injection and production rate of the target gas storage facility is calculated based on the maximum gas injection and production rate of the salt cavern and the maximum gas injection and production rate of the wellbore.

[0063] According to some embodiments of this application, such as Figure 1 As shown, the maximum injection and production rate determination scheme for salt cavern compressed air energy storage proposed in this application mainly includes: a basic data acquisition system, a maximum injection and production rate determination method based on cavity safety (based on cavity contraction index and cavity stability index), a maximum injection and production rate determination method based on wellbore safety (based on wellbore erosion and steam condensation), and a maximum injection and production rate determination method.

[0064] Furthermore, the mechanical parameters include: salt cavern mechanical parameters, wellbore mechanical parameters, and surrounding rock mechanical parameters of the salt cavern; among which,

[0065] Mechanical parameters of salt caverns, including the radius of salt caverns at different depths;

[0066] Wellbore mechanical parameters, including: the inner and outer diameters of the gas production tubing and the inner and outer diameters of the casing;

[0067] Mechanical parameters of the surrounding rock of salt caverns include: elastic modulus, Poisson's ratio, shear strength, internal friction angle, and cohesion.

[0068] Furthermore, the maximum gas injection and production rate of the salt cavern is calculated based on mechanical parameters, including:

[0069] A mechanical model of the salt cavern was constructed based on the mechanical parameters;

[0070] Deformation data of the salt cavern cavity and surrounding rock were calculated using a mechanical model. The deformation data of the salt cavern cavity included the volume shrinkage rate of the salt cavern cavity. The deformation data of the surrounding rock included the maximum depth of plastic deformation of the surrounding rock.

[0071] The maximum gas injection and production rate of the salt cavern was calculated based on deformation data.

[0072] Furthermore, the maximum gas injection and production rate of the salt cavern is calculated based on a mechanical model, including: using a first preset value for the volume shrinkage rate of the salt cavern cavity and a second preset value for the maximum depth of plastic deformation of the surrounding rock being less than a second preset value as boundary conditions to calculate the maximum gas injection and production rate of the salt cavern.

[0073] Furthermore, the volume shrinkage rate of the salt cavern cavity was calculated using a mechanical model, employing the following formulas:

[0074]

[0075] Where E represents the volume shrinkage rate of the salt cavern cavity; Q E This indicates the gas extraction rate that satisfies the cavity contraction condition; ΔV represents the volume shrinkage rate of the salt cavern cavity under the gas extraction rate that satisfies the cavity shrinkage condition; ΔV represents the volume change of the cavity; V represents the initial volume of the cavity.

[0076] Furthermore, the maximum depth of plastic deformation of the surrounding rock of the salt cavern was calculated using a mechanical model, and the formulas used included:

[0077]

[0078] Where σ1 represents the maximum principal stress; σ3 represents the minimum principal stress; c represents the cohesion of the rock; and φ represents the internal friction angle of the rock.

[0079] According to some embodiments of this application, a method for calculating the maximum gas injection and production rate of a salt cavern includes:

[0080] (1) Obtaining basic parameters

[0081] Obtain the cavity morphology of the salt cavern, i.e., the radius of the salt cavern at different depths; the wellbore structure, i.e., the inner and outer diameters of the gas production tubing and the inner and outer diameters of the casing; and the mechanical parameters of the surrounding rock of the salt cavern, such as elastic modulus, Poisson's ratio, shear strength, internal friction angle, and cohesion.

[0082] (2) Determination of the maximum gas injection and production rate based on cavity safety

[0083] A three-dimensional geomechanical model of compressed air energy storage in salt caverns is constructed. The model uses the geometry of the salt cavern and the mechanical parameters of the surrounding rock, such as elastic modulus, Poisson's ratio, and shear strength, as input parameters. Numerical calculations using FLAC3D can obtain the distribution of the plastic zone in the surrounding rock and the creep shrinkage value of the cavity under different extraction rates. At the maximum injection-production rate, the salt cavern should meet the following design criteria: ① The cavity can continuously maintain the gas storage and extraction capacity required for compressed air energy storage; ② It can maintain the mechanical stability of the cavity. Mathematically, this can be expressed as:

[0084] ① The volume shrinkage rate of the cavity is less than 30% over a 30-year operating cycle:

[0085]

[0086] Where E is the volume shrinkage rate of the cavity; Q E The gas extraction rate is required to meet the cavity contraction conditions; ΔV represents the volume shrinkage rate of the salt cavern cavity under the gas extraction rate that satisfies the cavity shrinkage condition; ΔV is the volume change of the cavity; V is the initial volume of the cavity.

[0087] ②The maximum depth at which the surrounding rock undergoes plastic deformation is less than 50% of the width of the adjacent salt cavern pillar:

[0088]

[0089] Where Dmax is the maximum depth at which the surrounding rock undergoes plastic deformation; Q D To ensure the gas extraction rate meets the requirements for long-term operational stability of the cavity; This represents the maximum depth at which the surrounding rock undergoes plastic deformation under a gas production rate that satisfies the long-term operational stability of the cavity; d k The width of the pillars of adjacent salt caverns.

[0090] The following relationship is used to determine whether plastic deformation has occurred in the surrounding rock:

[0091]

[0092] Where σ1 and σ3 refer to the maximum and minimum principal stresses, respectively, which can be obtained through numerical simulation of the geological model; C is the cohesion of the rock. The internal friction angle of the rock.

[0093] Furthermore, the maximum gas injection and production rate of the wellbore is calculated based on mechanical parameters, including: taking the maximum gas production of the salt cavern being less than the wellhead erosion flow rate and the water vapor mass concentration in the wellbore being greater than the critical saturated water vapor mass concentration as boundary conditions, and then calculating the maximum gas injection and production rate of the wellbore.

[0094] Furthermore, the calculation formula for wellhead erosion flow rate includes:

[0095]

[0096] Among them, Q S denoted by erosion flow rate; C is an empirical constant; D represents the inner diameter of the gas sampling tubing; p represents the gas pressure inside the tubing; r represents the relative density of the gas; Z represents the compressibility factor of the gas; and T represents the gas temperature.

[0097] Furthermore, the calculation formula for the water vapor mass concentration in the wellbore includes:

[0098]

[0099] Among them, W w P represents the mass concentration of water vapor in the wellbore. sw denoted by saturated vapor pressure of water; p represents gas pressure inside the tube; T represents gas temperature; x1, x2, x3, x4, x5, x6, x7 are empirical constants.

[0100] Furthermore, the formula for calculating the gas temperature T includes:

[0101]

[0102] Where A represents the cross-sectional area of ​​the gas injection string; ρ represents the gas density; C v,gThe constant-pressure specific heat of the gas is represented by μ; t represents the running time; μ represents the specific heat of the gas at constant pressure. jT The Joule-Thomson coefficient represents the gas flow rate; v represents the gas velocity; z represents the depth; g represents the gravitational acceleration; and Qe represents the heat absorbed by the gas from the environment.

[0103] According to some embodiments of this application, the method for calculating the second maximum gas injection-production rate includes:

[0104] (3) Method for determining the maximum gas injection and production rate based on wellbore safety

[0105] During compressed air energy storage operation in salt cavern gas storage facilities, the high-speed gas flow carries heavy particles and acidic substances, including droplets, sediment particles, and gas molecules, which repeatedly exert mechanical and chemical effects on the inner wall of the injection and production pipes. This can potentially cause erosion damage such as pipe wall cutting, peeling, and perforation. This phenomenon is known as well string erosion. For salt cavern gas storage facilities with high gas-liquid ratios, high production rates, and the potential for sand contamination, well string erosion is a significant concern, and the maximum daily gas production must be limited to below the wellhead erosion flow rate.

[0106]

[0107] In the formula, Q S denoted as erosion flow rate; C is an empirical constant; D is the inner diameter of the gas sampling tubing; p is the gas pressure inside the tubing; r is the relative density of the gas; Z is the compressibility factor of the gas; and T is the gas temperature.

[0108] During the gas production stage, due to energy consumption and exchange such as the Joule-Thomson effect, gas expansion, frictional work, and heat transfer, the temperature and pressure of the gas in the cavity and tubing will continuously decrease over time. When the temperature inside the tubing drops below the natural gas-water dew point under these conditions, the supersaturated portion of the natural gas in the tubing will condense and gradually produce liquid desalinated water under the distillation effect of the long tubing length. This condensate water easily adheres to the tubing surface in the form of a "water film," reducing the gas flow cross-section and increasing resistance. When a large amount of condensate water is produced, it is very likely to slide back along the tubing wall to the bottom of the well, dissolving the salt in the open hole section and the top of the cavity, forming grooves, causing the tubing and casing shoes to loosen and become unstable. In severe cases, this can lead to gas storage shutdown, wellbore failure, gas leakage, and other hazards.

[0109] The water vapor concentration in the wellbore should be greater than the critical saturated water vapor concentration at the maximum gas production rate, as follows:

[0110]

[0111] Where Wcv is the critical saturated water vapor mass concentration; Q H W represents the corresponding maximum gas extraction rate. wThe mass concentration of saturated water vapor in the gas; The calculation method for the saturated water vapor mass concentration in the gas at the maximum gas extraction rate is as follows:

[0112]

[0113] Where T is the gas temperature, calculated as follows:

[0114]

[0115] Where A is the cross-sectional area of ​​the gas injection string; ρ is the gas density; C v,g t is the isobaric specific heat of the gas; t is the running time; μ jT denoted by ω, where ω is the Joule-Thomson coefficient of the gas; v is the gas flow velocity; z is the depth; g is the acceleration due to gravity; and Qe is the heat absorbed by the gas from the environment.

[0116] Psw is the saturated vapor pressure of water, calculated as follows:

[0117]

[0118] By combining the above equations, we can obtain Q. H The maximum gas production rate is determined by taking into account the condensate water effect.

[0119] Furthermore, based on the maximum injection-production rate of the salt cavern and the maximum injection-production rate of the wellbore, the maximum injection-production rate of the target gas storage is calculated, including:

[0120] The minimum value between the maximum gas injection / production rate of the salt cavern and the maximum gas injection / production rate of the wellbore is taken as the maximum gas injection / production rate of the target gas storage facility.

[0121] According to some embodiments of this application, the method for determining the maximum gas injection and recovery rate is as follows:

[0122] (4) Maximum gas injection and production rate design

[0123] The above scheme yields the design values ​​for the maximum gas production rate of four salt cavern compressed gas storage systems. Under theoretical conditions, the minimum value among them is taken as the comprehensive design value for the maximum injection and production rate, i.e.:

[0124] Q min ={Q E Q D Q S Q H} min

[0125] Among them, Q min This is the final design value for the maximum gas injection and production rate.

[0126] Based on the same technological concept, such as Figure 2 As shown, this application also proposes a system for determining the maximum injection-production rate of compressed air storage in salt caverns, comprising:

[0127] The parameter acquisition module is used to acquire the mechanical parameters of the salt cavern and wellbore of the target gas storage facility;

[0128] The first calculation module is used to calculate the maximum gas injection and production rate of the salt cavern based on the mechanical parameters.

[0129] The second calculation module is used to calculate the maximum gas injection and production rate of the wellbore based on the mechanical parameters.

[0130] The third calculation module is used to calculate the maximum gas injection rate of the target gas storage facility based on the maximum gas injection and production rate of the salt cavern and the maximum gas injection and production rate of the wellbore.

[0131] It is obvious that those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for determining the maximum gas injection and production rate of compressed air energy storage in salt caverns, characterized in that, include: Obtain the mechanical parameters of the salt cavern and wellbore of the target gas storage facility; Calculate the maximum gas injection and production rate of the salt cavern based on the mechanical parameters; Calculate the maximum gas injection / production rate of the wellbore based on the mechanical parameters; The maximum gas injection and production rate of the target gas storage facility is calculated based on the maximum gas injection and production rate of the salt cavern and the maximum gas injection and production rate of the wellbore.

2. The method as described in claim 1, characterized in that, The mechanical parameters include: salt cavern mechanical parameters, wellbore mechanical parameters, and surrounding rock mechanical parameters of the salt cavern; wherein, The mechanical parameters of the salt cavern include: the radius of the salt cavern at different depths; The wellbore mechanical parameters include: the inner and outer diameters of the gas production tubing and the inner and outer diameters of the casing; The mechanical parameters of the surrounding rock of the salt cavern include: elastic modulus, Poisson's ratio, shear strength, internal friction angle, and cohesion of the surrounding rock.

3. The method as described in claim 2, characterized in that, Calculating the maximum gas injection and production rate of the salt cavern based on the aforementioned mechanical parameters includes: A mechanical model of the salt cavern is constructed based on the aforementioned mechanical parameters; The deformation data of the salt cavern cavity and the surrounding rock are calculated using the mechanical model. The deformation data of the salt cavern cavity includes the volume shrinkage rate of the salt cavern cavity. The deformation data of the surrounding rock includes the maximum depth of plastic deformation of the surrounding rock. The maximum gas injection and production rate of the salt cavern is calculated based on the deformation data.

4. The method as described in claim 3, characterized in that, The maximum gas injection and production rate of the salt cavern is calculated based on the mechanical model, including: using a first preset value of the volume shrinkage rate of the salt cavern cavity and a second preset value of the maximum depth of plastic deformation of the surrounding rock being less than a second preset value as boundary conditions, to calculate the maximum gas injection and production rate of the salt cavern.

5. The method as described in claim 4, characterized in that, The formula used to calculate the volume shrinkage rate of the salt cavern cavity through the aforementioned mechanical model includes: Where E represents the volume shrinkage rate of the salt cavern cavity; Q E E| represents the gas extraction rate that satisfies the cavity contraction condition; QE ΔV represents the volume shrinkage rate of the salt cavern cavity under the gas extraction rate that satisfies the cavity shrinkage condition; ΔV represents the volume change of the cavity; V represents the initial volume of the cavity.

6. The method as described in claim 4, characterized in that, The formulas used to calculate the maximum depth of plastic deformation in the surrounding rock of the salt cavern through the aforementioned mechanical model include: Where σ1 represents the maximum principal stress; σ3 represents the minimum principal stress; c represents the cohesion of the rock; and φ represents the internal friction angle of the rock.

7. The method as described in claim 2, characterized in that, The maximum gas injection and production rate of the wellbore is calculated based on the mechanical parameters, including: taking the maximum gas production of the salt cavern being less than the wellhead erosion flow rate and the water vapor mass concentration in the wellbore being greater than the critical saturated water vapor mass concentration as boundary conditions, and then calculating the maximum gas injection and production rate of the wellbore.

8. The method as described in claim 7, characterized in that, The calculation formula for the wellhead erosion flow rate includes: Among them, Q S denoted by erosion flow rate; C is an empirical constant; D represents the inner diameter of the gas sampling tubing; p represents the gas pressure inside the tubing; r represents the relative density of the gas; Z represents the compressibility factor of the gas; and T represents the gas temperature.

9. The method as described in claim 8, characterized in that, The formula for calculating the water vapor mass concentration in the wellbore includes: Among them, W w P represents the mass concentration of water vapor in the wellbore. sw denoted by saturated vapor pressure of water; p represents gas pressure inside the tube; T represents gas temperature; x1, x2, x3, x4, x5, x6, x7 are empirical constants.

10. The method as described in claim 8 or 9, characterized in that, The calculation formula for the gas temperature T includes: Where A represents the cross-sectional area of ​​the gas injection string; ρ represents the gas density; C v,g The constant-pressure specific heat of the gas is represented by μ; t represents the running time; μ represents the specific heat of the gas at constant pressure. jT The Joule-Thomson coefficient represents the gas flow rate; v represents the gas velocity; z represents the depth; g represents the gravitational acceleration; and Qe represents the heat absorbed by the gas from the environment.

11. The method as described in claim 1, characterized in that, Based on the maximum gas injection and production rate of the salt cavern and the maximum gas injection and production rate of the wellbore, the maximum gas injection and production rate of the target gas storage is calculated, including: The minimum value between the maximum gas injection / production rate of the salt cavern and the maximum gas injection / production rate of the wellbore is taken as the maximum gas injection / production rate of the target gas storage.

12. A system for determining the maximum gas injection and production rate of compressed air energy storage in salt caverns, characterized in that, include: The parameter acquisition module is used to acquire the mechanical parameters of the salt cavern and wellbore of the target gas storage facility; The first calculation module is used to calculate the maximum gas injection and production rate of the salt cavern based on the mechanical parameters. The second calculation module is used to calculate the maximum gas injection and production rate of the wellbore based on the mechanical parameters. The third calculation module is used to calculate the maximum gas injection rate of the target gas storage facility based on the maximum gas injection and production rate of the salt cavern and the maximum gas injection and production rate of the wellbore.

13. The maximum gas injection and production rate determination system for salt cavern compressed air energy storage as described in claim 12, characterized in that, The method executed by the first calculation module includes: A mechanical model of the salt cavern is constructed based on the aforementioned mechanical parameters; The deformation data of the salt cavern cavity and the surrounding rock are calculated using the mechanical model. The deformation data of the salt cavern cavity includes the volume shrinkage rate of the salt cavern cavity. The deformation data of the surrounding rock includes the maximum depth of plastic deformation of the surrounding rock. The maximum gas injection and production rate of the salt cavern is calculated based on the deformation data.

14. The maximum gas injection and production rate determination system for salt cavern compressed air energy storage as described in claim 12, characterized in that, The second calculation module executes the following methods: Using the boundary conditions that the maximum gas production rate of the salt cavern is less than the wellhead erosion flow rate and the water vapor mass concentration in the wellbore is greater than the critical saturated water vapor mass concentration, the maximum gas injection and production rate of the wellbore is calculated.

15. The maximum gas injection and production rate determination system for salt cavern compressed air energy storage as described in claim 12, characterized in that, The method executed by the third calculation module includes: The minimum value between the maximum gas injection / production rate of the salt cavern and the maximum gas injection / production rate of the wellbore is taken as the maximum gas injection / production rate of the target gas storage.

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