Underground gas storage gas leakage monitoring and splitting risk assessment method, device and equipment

Abstract

The invention provides a gas leakage monitoring and splitting risk assessment method, device and equipment for an underground gas storage. The method comprises the following steps: acquiring monitoring data of the underground gas storage; determining gas leakage and an environment characteristic matrix of the underground gas storage according to the monitoring data; performing gas leakage monitoring on the underground gas storage according to the gas leakage amount and the change characteristic trend of the monitoring data, and determining the gas leakage type of the underground gas storage; positioning a gas leakage point of the underground gas storage according to the environment characteristic matrix and the monitoring data; evaluating the splitting risk of the underground gas storage according to the monitoring data of the gas leakage point; and generating an assessment report according to the assessment results of the gas leakage type and the splitting risk. The splitting risk of the underground gas storage is evaluated by judging the leakage type of gas leakage and according to the monitoring data of the gas leakage point, permeation and damage are distinguished, and accurate damage positioning and subsequent splitting risk evaluation are achieved.

Description

Technical Field

[0001] This application relates to the field of underground gas storage technology, and in particular to a method, apparatus and equipment for monitoring gas leakage and assessing the risk of fracturing in underground gas storage. Background Technology

[0002] Underground gas storage facilities, as modern energy infrastructure, utilize flexible media such as polymer composites to construct sealing layers. These layers effectively adapt to geological deformation, enabling the safe storage of large-scale energy media such as natural gas and hydrogen. They play a crucial role in energy peak shaving, strategic reserves, and pipeline network balancing. However, due to long-term exposure to alternating loads, temperature variations, and groundwater erosion, the sealing layers are prone to microscopic damage. Without real-time leakage monitoring, even small leaks can gradually expand, not only wasting energy but also potentially posing an explosion risk and causing environmental pollution. Furthermore, accumulated geological stress can lead to progressive splitting of the flexible materials, jeopardizing the overall structural safety.

[0003] However, traditional solutions mainly use single-parameter analysis, such as determining the location of the leak based on changes in internal pressure or flow rate measurement. They only focus on leak detection or leakage volume assessment, and lack the ability to distinguish between penetration and damage, accurately locate damage, and assess subsequent rupture risks. Summary of the Invention

[0004] The purpose of this application is to provide a method, device, and electronic equipment for monitoring gas leaks and assessing fracture risks in underground gas storage facilities. This can solve the problems of existing technologies that focus on gas leak detection or leakage assessment, lack the ability to distinguish between infiltration and damage, cannot accurately locate damage, and fail to conduct subsequent fracture risk assessment.

[0005] In a first aspect, embodiments of this application provide a method for monitoring gas leakage and assessing fracturing risk in an underground gas storage facility, the method comprising: Obtain monitoring data from underground gas storage facilities; The leakage rate and environmental characteristic matrix of the underground gas storage facility are determined based on the monitoring data. Based on the leakage volume and the changing characteristics and trends of the monitoring data, the underground gas storage facility is monitored for leakage to determine the type of leakage. The leak point of the underground gas storage is located based on the environmental feature matrix and the monitoring data; The risk of fracturing in the underground gas storage facility is assessed based on the monitoring data of the leak points. An assessment report is generated based on the assessment results of the gas leak type and the splitting risk.

[0006] Optionally, the monitoring data includes at least: gas data, flow data, pressure data, and material data of the underground gas storage facility; the leakage includes: a first leakage and a second leakage. The process of determining the leakage rate and environmental characteristic matrix of the underground gas storage facility based on the monitoring data includes: The first leakage amount within a preset time range is calculated based on the gas data, the flow rate data, and the pressure data; the first leakage amount represents the actual leakage amount of the underground gas storage facility. The second leakage rate is calculated using Darcy's law based on the pressure data and the material data; the second leakage rate represents the theoretical leakage rate calculated based on the materials of the underground gas storage facility. The acoustic, temperature, and pressure features of the monitoring data are extracted to construct an environmental feature matrix.

[0007] Optionally, calculating the first leakage within a preset time range based on the gas data, the flow rate data, and the pressure data includes: The cumulative leakage mass within a preset time range is calculated using the ideal gas law and the flow difference method based on the gas data, the flow data, and the pressure data. Calculate the first leakage amount based on the cumulative leakage mass; The formula for calculating the first leakage mass is as follows:

[0008]

[0009] Wherein, P( (time) Average gas storage pressure in underground gas storage facilities; T( (time) The average temperature inside the underground gas storage facility; V is the volume of the underground gas storage facility; R air is the specific gas constant of air; m leak (t) The cumulative leakage mass up to time t; The starting time; m( )for The initial gas mass in the underground gas storage facility at any given time; This refers to the mass flow rate entering the gas storage tank through the intake pipe. This refers to the mass flow rate of gas leaving the underground gas storage facility through the outlet pipe. P(t) represents the net mass of gas injected during the time interval; P(t) represents the average gas pressure in the underground gas storage at time t; and T(t) represents the average temperature in the underground gas storage at time t. The formula for calculating the first leakage volume is as follows:

[0010] Among them: Q leak ( (time) The first leakage volume of the underground gas storage facility, that is, the cumulative actual leakage volume at time t; m leak (t) represents the first leakage mass up to time t, which is also the cumulative actual leakage mass; air ( Let P(t) be the air density at time t, calculated based on the average gas pressure P(t) and the average temperature T(t) in the underground gas storage at time t.

[0011] Optionally, the step of calculating the second leakage rate using Darcy's law based on the pressure data and the material data includes: The permeability of the underground gas storage facility is determined based on the material data. The second leakage rate is calculated using Darcy's law based on the permeability and the material data. The formula for calculating the second leakage amount is as follows:

[0012] Where: k is the permeability, determined by material testing; L is the thickness of the sealing layer; A is the permeability area, which is also the inner surface area of ​​the underground gas storage facility; The pressure difference between the pressure inside the underground gas storage facility and the external pressure. This refers to the dynamic viscosity of the gas.

[0013] Optionally, the changing characteristic trends include: acoustic characteristics, temperature change trends, pressure change trends, and strain trends; The process of monitoring the underground gas storage facility for leaks based on the leakage volume and the changing trends of the monitoring data, and determining the type of leak, includes: Calculate the permeability ratio based on the first and second leakage rates; The type of gas leakage in the underground gas storage facility is determined based on the permeability ratio, the acoustic characteristics, the temperature change trend, the pressure change trend, and the strain trend.

[0014] Optionally, determining the type of gas leakage in the underground gas storage facility based on the permeability ratio, the acoustic characteristics, the temperature change trend, the pressure change trend, and the strain trend includes: If the permeability ratio is greater than or equal to the permeability threshold, and the acoustic characteristics have preset frequency band energy, the temperature change trend and the pressure change trend have local fluctuations, and the strain trend is greater than or equal to the strain trend threshold, the leakage type of the underground gas storage is a rupture leakage; otherwise, the leakage type of the underground gas storage is determined to be a permeation leakage.

[0015] Optionally, locating the leak point of the underground gas storage facility based on the environmental feature matrix and the monitoring data includes: Calculate the confidence level of the monitoring points based on the environmental feature matrix and the monitoring data; If the confidence level is less than or equal to the confidence level threshold, the monitoring point is identified as a leak point; The leak point is located based on the monitoring data, the sensor number corresponding to the monitoring data, and the similarity between the sensors.

[0016] Optionally, calculating the confidence level of the monitoring points based on the environmental feature matrix and the monitoring data includes: Calculate the variance of each monitoring point based on the environmental feature matrix and the eigenvalues ​​of the monitoring data; The confidence level of each monitoring point is determined based on the variance. The confidence level is calculated using the following formula:

[0017] in: Let i be the confidence level of monitoring point i; The environmental feature matrix for monitoring point i; Let i be the acoustic characteristic value of the monitoring point i; The temperature characteristic value of monitoring point i; The pressure characteristic value at monitoring point i; the variance vector Var( ) represents the variance of the j-th feature component in the environmental feature matrix within the monitoring window.

[0018] Optionally, locating the leak point based on the monitoring data, the sensor number corresponding to the monitoring data, and the similarity between the sensors includes: The similarity between data collected by different sensors is calculated. The leak point is located based on the time delay corresponding to the similarity that meets preset conditions; The formula for calculating the similarity is as follows:

[0019] in: (τ) is the normalized cross-correlation function of sensor i and sensor j, reflecting the similarity of the pressure waveforms of sensor i and sensor j under time delay τ; i and j are the sensor numbers. (t) represents the pressure value of sensor i at time t; (t) represents the pressure value of sensor j at time t; Let be the average pressure value of sensor i within the time interval [t0, t0+τ]. These are the average pressure values ​​of sensor j within time [t0, t0+τ], respectively; For monitoring window time.

[0020] Optionally, the assessment of the fracturing risk of the underground gas storage facility based on the monitoring data of the leak point includes: Calculate the air pressure distribution at the leak point based on the monitoring data of the leak point; The minimum principal stress and tensile strength of the surrounding rock of the underground gas storage facility are determined based on the geological survey report of the underground gas storage facility. The risk of splitting at the leak point is determined based on the gas pressure distribution, the minimum principal stress of the surrounding rock, and the tensile strength of the surrounding rock.

[0021] Optionally, calculating the air pressure distribution at the leak point based on the monitoring data of the leak point includes: The air pressure distribution at the leak point is determined based on the preset crack length at the leak point and the tail pressure at the leak point in the monitoring data. The formula for the air pressure distribution is as follows:

[0022] in: The pressure at the leak point; This represents the gas pressure distribution along coordinate x within a pre-defined crack at the leak point, where x is the length along the pre-defined crack. Spatial coordinates of direction; The tail end pressure of the pre-set crack is used in the monitoring data.

[0023] Optionally, determining whether there is a risk of splitting at the leak point based on the gas pressure distribution, the minimum principal stress of the surrounding rock, and the tensile strength of the surrounding rock includes: The pressure at the leak point is determined by iterating the pressure distribution under the mass conservation condition. Determine whether the pressure at the fracture site is greater than the sum of the minimum principal stress of the surrounding rock and the tensile strength of the surrounding rock according to the judgment formula; If the pressure at the breach is greater than the sum of the minimum principal stress of the surrounding rock and the tensile strength of the surrounding rock, the leak point is at risk of splitting. The formula for determining the risk of splitting is as follows:

[0024] in: The pressure at the leak point; This represents the minimum principal stress of the surrounding rock. It represents the tensile strength of the surrounding rock.

[0025] Secondly, embodiments of this application provide a device for monitoring gas leakage and assessing fracturing risk in an underground gas storage facility, the device comprising: The data acquisition module is used to acquire monitoring data of the underground gas storage facility, including internal monitoring data and external monitoring data. The data processing module is used to determine the leakage amount and environmental characteristic matrix of the underground gas storage facility based on the monitoring data. The gas leakage type determination module is used to monitor the underground gas storage facility based on the gas leakage amount and the changing trend of the monitoring data, and to determine the gas leakage type of the underground gas storage facility. A leak location module is used to locate the leak point of the underground gas storage facility based on the environmental feature matrix and the monitoring data. The splitting risk assessment module is used to assess the splitting risk of the underground gas storage facility based on the monitoring data of the leak point. An assessment report generation module is used to generate an assessment report based on the assessment results of the gas leak type and the splitting risk.

[0026] Thirdly, embodiments of this application provide an electronic device, including: a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the method described above.

[0027] Fourthly, embodiments of this application provide a computer-readable storage medium on which a computer program is stored, which, when executed by a processor, implements the method described above.

[0028] Compared with the prior art, the embodiments of this application have the following advantages: The method for monitoring gas leakage and assessing fracture risk in underground gas storage facilities in this embodiment includes: acquiring monitoring data of the underground gas storage facility; determining the leakage volume and environmental characteristic matrix of the underground gas storage facility based on the monitoring data; monitoring the leakage volume and the changing trends of the monitoring data to determine the leakage type of the underground gas storage facility; locating the leakage point of the underground gas storage facility based on the environmental characteristic matrix and the monitoring data; assessing the fracture risk of the underground gas storage facility based on the monitoring data of the leakage point; and generating an assessment report based on the assessment results of the leakage type and fracture risk. By determining the leakage type and assessing the fracture risk of the underground gas storage facility based on the monitoring data of the leakage point, permeation and damage can be distinguished, achieving precise location of damage and subsequent fracture risk assessment. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a flowchart illustrating the steps of a method for monitoring gas leakage and assessing fracturing risk in an underground gas storage facility, as provided in an embodiment of this application. Figure 2 This is a schematic diagram of the structure of an underground gas storage leakage monitoring and fracturing risk assessment device provided in an embodiment of this application; Figure 3 This is a schematic diagram of an electronic device provided in an embodiment of this application; Figure 4 This is a schematic diagram of a computer-readable storage medium provided in an embodiment of this application. Detailed Implementation

[0031] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0032] The terms "first," "second," etc., used in this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein. Furthermore, in this application, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0033] The following description, in conjunction with the accompanying drawings, details a method, apparatus, electronic device, and storage medium for monitoring gas leakage and assessing fracturing risk in an underground gas storage facility, provided by this application, through specific embodiments and application scenarios.

[0034] Underground gas storage facilities, as modern energy infrastructure, utilize flexible media such as polymer composites to construct sealing layers. These layers effectively adapt to geological deformation, enabling the safe storage of large-scale energy media such as natural gas and hydrogen. They play a crucial role in energy peak shaving, strategic reserves, and pipeline network balancing. However, due to long-term exposure to alternating loads, temperature variations, and groundwater erosion, the sealing layers are prone to microscopic damage. Without real-time leakage monitoring, even small leaks can gradually expand, not only wasting energy but also potentially posing an explosion risk and causing environmental pollution. Furthermore, accumulated geological stress can lead to progressive splitting of the flexible materials, jeopardizing the overall structural safety.

[0035] However, traditional solutions mainly use single-parameter analysis, such as determining the location of the leak based on changes in internal pressure or flow rate measurement. They only focus on leak detection or leakage volume assessment, and lack the ability to distinguish between penetration and damage, accurately locate damage, and assess subsequent rupture risks.

[0036] Reference Figure 1 The diagram illustrates a flowchart of the steps involved in a method for monitoring gas leakage and assessing fracturing risk in an underground gas storage facility, as provided in this embodiment of the application. Specifically, the method may include the following: Step S101: Obtain monitoring data from the underground gas storage facility; In this embodiment, pressure sensors, temperature sensors, flow meters, and sealing layer strain gauges are installed inside the underground gas storage facility, and a temperature-pressure-sound monitoring network is deployed outside the lining to acquire monitoring data at each monitoring point. In order to ensure that the timestamps of the monitoring data can be aligned, all sensors are sampled synchronously through a unified acquisition system.

[0037] Specifically, for the interior of an underground gas storage facility, multiple sets of high-precision pressure sensors can be installed along the axial direction of the storage facility. Each set of pressure sensors should have at least two points, located at 1 / 4 and 3 / 4 of the height from the bottom plate, respectively. Temperature sensors should be installed in conjunction with the pressure sensors, within the preset range of the pressure sensors. Mass flow meters with a range not less than the maximum operating flow rate should be installed on the inlet and outlet pipes of the underground gas storage facility. Strain gauges should be attached to the back of the flexible sealing layer or the inner wall of the lining of the underground gas storage facility every 45° circumferentially to monitor circumferential strain changes.

[0038] For the exterior of the underground gas storage facility, multiple monitoring sections can be set along the axial direction of the concrete lining. Each section can be arranged with a preset number of monitoring points along the circumference to form a spiral or grid structure for section monitoring. Temperature and pressure sensors can be installed at each monitoring point to detect temperature drops and pressure fluctuations caused by leakage. High-sensitivity microphones can also be installed at the monitoring points to capture high-frequency sound waves generated by air jets.

[0039] By collecting multi-dimensional monitoring data, we can provide multi-modal and accurate data for subsequent determination of gas leakage types and splitting risk assessment.

[0040] Step S102: Determine the leakage rate and environmental characteristic matrix of the underground gas storage facility based on the monitoring data; In this embodiment, the leakage of the underground gas storage is calculated based on the multimodal data of each monitoring point in the monitoring data, and an environmental feature matrix is ​​constructed based on this multimodal data.

[0041] Step S103: Based on the leakage amount and the changing trend of the monitoring data, perform leakage monitoring on the underground gas storage facility to determine the leakage type of the underground gas storage facility; In this embodiment, the changing characteristics and trends of the monitoring data are determined based on the monitoring data. Then, the leakage type of the underground gas storage is determined from multiple dimensions based on the leakage volume and the changing characteristics and trends. This avoids the data limitations of judging the leakage type by a single indicator and improves the monitoring accuracy of the leakage type.

[0042] Step S104: Locate the leak point of the underground gas storage facility based on the environmental feature matrix and the monitoring data; In this embodiment, the environmental feature matrix is ​​a low-dimensional set of environmental features composed of the features of the monitoring data synchronously acquired by monitoring point i within the monitoring window. The suspected leakage range is delineated by calculating the variance vector or principal component eigenvalue of each feature component, thereby locating the leak point.

[0043] Step S105: Assess the risk of fracturing of the underground gas storage facility based on the monitoring data of the leak point; Traditional methods rarely consider the impact of gas leakage on concrete lining and surrounding rock splitting, and do not establish a coupled assessment model of operational gas pressure and rock mechanics. In this embodiment, the splitting risk of the underground gas storage facility will be assessed based on the coupling relationship between operational gas pressure and rock mechanics, using monitoring data from the leakage points.

[0044] Step S106: Generate an assessment report based on the assessment results of the gas leakage type and the splitting risk.

[0045] After determining the type of gas leak and the assessment results of the splitting risk, an assessment report is generated based on the assessment results to provide risk warning. The assessment report includes at least: gas leakage volume, gas leak type, gas leak location, and maintenance recommendations. The maintenance recommendations can output the strategies to be taken in this scenario and the adjustment parameters of the underground gas storage based on the preset strategy library to avoid further expansion of the risk. Optionally, after taking appropriate measures to repair the underground gas storage facility based on the assessment report, the stability of the surrounding rock can be reassessed.

[0046] The method for monitoring gas leakage and assessing fracture risk in underground gas storage facilities in this embodiment includes: acquiring monitoring data of the underground gas storage facility; determining the leakage volume and environmental characteristic matrix of the underground gas storage facility based on the monitoring data; monitoring the leakage volume and the changing trends of the monitoring data to determine the leakage type of the underground gas storage facility; locating the leakage point of the underground gas storage facility based on the environmental characteristic matrix and the monitoring data; assessing the fracture risk of the underground gas storage facility based on the monitoring data of the leakage point; and generating an assessment report based on the assessment results of the leakage type and fracture risk. By determining the leakage type and assessing the fracture risk of the underground gas storage facility based on the monitoring data of the leakage point, permeation and damage can be distinguished, achieving precise location of damage and subsequent fracture risk assessment.

[0047] In one embodiment of this application, the monitoring data includes at least: gas data, flow rate data, pressure data, and material data of the underground gas storage facility; the leakage amount includes: a first leakage amount and a second leakage amount; The process of determining the leakage rate and environmental characteristic matrix of the underground gas storage facility based on the monitoring data includes: The first leakage amount within a preset time range is calculated based on the gas data, the flow rate data, and the pressure data; the first leakage amount represents the actual leakage amount of the underground gas storage facility. The second leakage rate is calculated using Darcy's law based on the pressure data and the material data; the second leakage rate represents the theoretical leakage rate calculated based on the materials of the underground gas storage facility. The acoustic, temperature, and pressure features of the monitoring data are extracted to construct an environmental feature matrix.

[0048] In this embodiment of the application, the monitoring data includes at least: gas data, flow data, pressure data and material data of the underground gas storage facility; wherein, the material data refers to the material properties of the flexible sealing material used in the underground gas storage facility.

[0049] During the assessment process, the first leakage amount at each monitoring point within a preset time range is calculated based on the gas data, flow data, and pressure data of the underground gas storage facility; whereby the first leakage amount represents the actual leakage amount of the underground gas storage facility. Since the permeability of the flexible sealing layer and the leakage due to breakage may be similar in magnitude, traditional solutions do not take into account the difference between the two and therefore cannot distinguish between breakage leakage and permeation leakage. This application further analyzes the flexible sealing material used in underground gas storage from the perspective of its material properties, and calculates the theoretical leakage of the underground gas storage, i.e., the second leakage, using Darcy's law based on pressure data and material data. Secondly, in order to improve the accuracy of leak location, this application extracts the corresponding acoustic wave feature values, temperature feature values ​​and pressure feature values ​​from the monitoring data of each monitoring point at different times, and constructs an environmental feature matrix through the acoustic wave feature values, temperature feature values ​​and pressure feature values.

[0050] This embodiment provides data to distinguish between rupture leaks and seepage leaks by using actual leakage volume and theoretical leakage volume related to material properties. By extracting the acoustic, temperature, and pressure characteristic values ​​of each monitoring point, an environmental characteristic matrix that changes over time is constructed from the three dimensions of acoustic waves, temperature, and pressure. This provides scientific and accurate data support for subsequently calculating the confidence level of the leak point and delineating suspected leak areas.

[0051] Optionally, before calculating the leakage rate and constructing the environmental feature matrix based on the collected monitoring data, zero-drift calibration needs to be performed before monitoring begins. High-frequency noise should be removed from the collected monitoring data using low-pass or wavelet filtering. The acoustic, temperature, and pressure data from external monitoring points should be normalized according to the following formula:

[0052] in, The monitoring data is normalized; The average value of the data in the class; This represents the standard deviation of this type of data.

[0053] In this embodiment of the application, the actual leakage mass and leakage volume, i.e. the first leakage mass and the first leakage volume, are calculated using the ideal gas law and the flow difference method. The formula for calculating the first leakage mass is as follows:

[0054]

[0055] Wherein, P( (time) Average gas storage pressure in underground gas storage facilities; T( (time) The average temperature inside the underground gas storage facility; V is the volume of the underground gas storage facility; R air is the specific gas constant of air; m leak (t) The cumulative leakage mass up to time t; The starting time; m( )for The initial gas mass in the underground gas storage facility at any given time; This refers to the mass flow rate entering the gas storage tank through the intake pipe. This refers to the mass flow rate of gas leaving the underground gas storage facility through the outlet pipe. The net mass of gas introduced during the time interval is represented by the integral part, which is achieved through numerical integration (such as the trapezoidal method). The mass flow rate data, pressure data, and temperature data provided by the flow meter belong to the same time base. P(t) is the average gas storage pressure in the underground gas storage at time t. T(t) is the average temperature in the underground gas storage at time t. First leakage volume The calculation formula is as follows:

[0056] Among them: Q leak ( (time) The first leakage volume of the underground gas storage facility, that is, the cumulative actual leakage volume at time t; m leak (t) represents the first leakage mass up to time t, which is also the cumulative actual leakage mass; air ( Let P(t) be the air density at time t, calculated based on the average gas pressure P(t) and the average temperature T(t) in the underground gas storage at time t.

[0057] In this embodiment of the application, based on the material properties of the flexible sealing layer used in the underground gas storage, the corresponding permeability can be determined first according to the material properties of the flexible sealing layer used in the underground gas storage, and then Darcy's law can be used to calculate the theoretical leakage of the underground gas storage, that is, the second leakage. Calculate the second leakage amount The formula is as follows;

[0058] Where: k is the permeability, determined by material testing; L is the thickness of the sealing layer; A is the permeability area, which is also the inner surface area of ​​the underground gas storage facility; The pressure difference between the pressure inside the underground gas storage facility and the external pressure. This refers to the dynamic viscosity of the gas.

[0059] Alternatively, if the permeability is determined by combining multiple layers of structure, the total permeability can be calculated using the equivalent formula for series seepage. The formula for calculating the total permeability is as follows:

[0060] in, is the equivalent permeability of the multi-layer composite structure; i is the layer number. Let be the thickness of the i-th layer; Let be the permeability of the i-th layer material.

[0061] This embodiment improves the versatility of calculating theoretical leakage by calculating the total permeability of underground gas storage in single-layer or multi-layer composite structures, making it suitable for underground gas storage with different structural designs. It calculates the theoretical leakage of the flexible sealing layer permeability using Darcy's law, providing data support for subsequent leakage determination.

[0062] In one embodiment of this application, the changing characteristic trends include: acoustic characteristics, temperature change trends, pressure change trends, and strain trends; The process of monitoring the underground gas storage facility for leaks based on the leakage volume and the changing trends of the monitoring data, and determining the type of leak, includes: Calculate the permeability ratio based on the first and second leakage rates; The type of gas leakage in the underground gas storage facility is determined based on the permeability ratio, the acoustic characteristics, the temperature change trend, the pressure change trend, and the strain trend.

[0063] In this embodiment, the changing characteristics include: acoustic characteristics, temperature change trend, pressure change trend, and strain trend. After calculating the actual leakage amount and the theoretical leakage amount, the corresponding permeability ratio is calculated. By combining the permeability ratio with the acoustic characteristics, temperature change trend, pressure change trend, and strain trend, the leakage type is classified, making the determination of the leakage type more accurate.

[0064] Specifically, the formula for calculating the permeability ratio is as follows:

[0065] in, This is the permeability ratio; This represents the actual amount of air leakage, also known as the first leakage volume. This is the theoretical leakage rate, also known as the second leakage rate.

[0066] In one embodiment of this application, determining the type of gas leakage in the underground gas storage facility based on the permeability ratio, the acoustic characteristics, the temperature change trend, the pressure change trend, and the strain trend includes: If the permeability ratio is greater than or equal to the permeability threshold, and the acoustic characteristics have preset frequency band energy, the temperature change trend and the pressure change trend have local fluctuations, and the strain trend is greater than or equal to the strain trend threshold, the leakage type of the underground gas storage is a rupture leakage; otherwise, the leakage type of the underground gas storage is determined to be a permeation leakage.

[0067] In this embodiment, the types of air leakage include rupture leakage and seepage leakage. When the permeability ratio is greater than or equal to the permeability threshold, the acoustic characteristics are abnormal, the temperature change trend and pressure change trend are abnormal, and the strain trend changes abruptly, the monitoring point is determined to be a rupture leakage; otherwise, it is determined to be a seepage leakage.

[0068] In practical applications, when the permeability ratio When the value is close to 1 and changes steadily, it indicates that the leakage is mainly caused by permeability. When it is significantly greater than 1 in a short period of time (such as exceeding 1.5–2.0), it indicates that there may be a rupture leak. Therefore, a permeability threshold can be set to make a preliminary judgment on the type of leakage. Then, the characteristics of sound waves, temperature change trends, pressure change trends and strain trends are combined to assist in the judgment of the type of leakage.

[0069] In auxiliary judgment, a short-time Fourier transform can be performed on the acoustic signal. If a specific frequency band energy that is continuously higher than the background noise appears at a certain monitoring point, it can be determined that there is an abnormal acoustic characteristic at that monitoring point. When the outer wall temperature drops locally and the pressure fluctuates locally, it can be determined that there are abnormal temperature and pressure change trends at that monitoring point. If the monitored value of a strain gauge at a monitoring point increases by more than a preset proportion of the basic strain in a short period of time, it can be determined that there is a sudden change in the strain trend at that monitoring point.

[0070] This embodiment utilizes the subtle characteristics of rupture leaks and seepage leaks to make a preliminary judgment on the type of gas leak by using the seepage ratio. It combines the judgment of abnormal acoustic characteristics, abnormal temperature and pressure change trends, and sudden changes in strain trends to assist in the judgment of the type of gas leak. It judges the type of gas leak from multiple dimensions, which solves the problem that existing methods only rely on pressure or flow rate to calculate the amount of gas leak, without fully considering factors such as temperature and inlet / outlet gas flow, resulting in large judgment errors and difficulty in distinguishing between seepage leaks and rupture leaks.

[0071] In one embodiment of this application, locating the leak point of the underground gas storage facility based on the environmental feature matrix and the monitoring data includes: Calculate the confidence level of the monitoring points based on the environmental feature matrix and the monitoring data; If the confidence level is less than or equal to the confidence level threshold, the monitoring point is identified as a leak point; The leak point is located based on the monitoring data, the sensor number corresponding to the monitoring data, and the similarity between the sensors.

[0072] In one embodiment of this application, calculating the confidence level of the monitoring point based on the environmental feature matrix and the monitoring data includes: Calculate the variance of each monitoring point based on the environmental feature matrix and the eigenvalues ​​of the monitoring data; The confidence level of each monitoring point is determined based on the variance. The confidence level is calculated using the following formula:

[0073] in: Let i be the confidence level of monitoring point i; The environmental feature matrix for monitoring point i; Let i be the acoustic characteristic value of the monitoring point i; The temperature characteristic value of monitoring point i; The pressure characteristic value at monitoring point i; the variance vector Var( ) represents the variance of the j-th feature component in the environmental feature matrix within the monitoring window.

[0074] In this embodiment, the environmental feature matrix is ​​a low-dimensional set of environmental features composed of the features of the monitoring data synchronously acquired by monitoring point i within the monitoring window, which can be represented as: ,in, For the environmental feature matrix of monitoring point i, For the acoustic characteristic value of monitoring point i, Temperature characteristic value of monitoring point i Let be the pressure characteristic value of monitoring point i.

[0075] Construct an environmental feature matrix for each external monitoring point i. Its variance vector can be calculated. Alternatively, principal component analysis (PCA) can be used to calculate eigenvalues. Define the confidence level of the leak point. The formula for calculating the confidence level is as follows:

[0076] in: Let i be the confidence level of monitoring point i; The environmental feature matrix for monitoring point i; Let i be the acoustic characteristic value of the monitoring point i; The temperature characteristic value of monitoring point i; The pressure characteristic value at monitoring point i; the variance vector Var( ) represents the variance of the j-th feature component in the environmental feature matrix within the monitoring window, reflecting the volatility / abnormality of that component.

[0077] when If the confidence level is less than or equal to the preset confidence threshold, the monitoring point is determined to be a leak point. Then, the leak range can be delineated by connecting the low-confidence monitoring points within the monitoring section, and the leak point can be located.

[0078] In one embodiment of this application, locating the leak point based on the monitoring data, the sensor number corresponding to the monitoring data, and the similarity between the sensors includes: The similarity between data collected by different sensors is calculated. The leak point is located based on the time delay corresponding to the similarity that meets preset conditions; The formula for calculating the similarity is as follows:

[0079] in: (τ) is the normalized cross-correlation function of sensor i and sensor j, reflecting the similarity of the pressure waveforms of sensor i and sensor j under time delay τ; i and j are the sensor numbers. (t) represents the pressure value of sensor i at time t; (t) represents the pressure value of sensor j at time t; Let be the average pressure value of sensor i within the time interval [t0, t0+τ]. These are the average pressure values ​​of sensor j within time [t0, t0+τ], respectively; For monitoring window time.

[0080] In this embodiment, before locating the leak point, it is necessary to perform cross-correlation analysis on the time series of pressure data collected inside the underground gas storage facility to obtain the time difference of pressure wave delay, and then locate the leak point based on the time difference of delay.

[0081] Specifically, it is necessary to first calculate the similarity between the data collected by different sensors; then determine the sensors whose similarity meets the preset conditions, and locate the leak point based on the time delay of these sensors. The formula for calculating similarity is as follows:

[0082] in: (τ) is the normalized cross-correlation function of sensor i and sensor j, reflecting the similarity of the pressure waveforms of sensor i and sensor j under time delay τ; i and j are the sensor numbers. (t) represents the pressure value of sensor i at time t; (t) represents the pressure value of sensor j at time t; Let be the average pressure value of sensor i within the time interval [t0, t0+τ]. These are the average pressure values ​​of sensor j within time [t0, t0+τ], respectively; For monitoring window time.

[0083] By setting a similarity threshold, sensors with a similarity greater than or equal to the threshold are identified as meeting preset conditions. Then, the leak point is located based on the propagation speed of the pressure wave and the distance between the sensors.

[0084] Optionally, to further verify the location of the leak, a small amount of inert tracer gas can be injected into the underground gas storage facility. The time and location of its appearance can be detected by external sampling to determine the leak path. By using multi-source monitoring and similarity analysis, the leak point can be accurately located, allowing for repairs to be carried out without prolonged shutdown.

[0085] In one embodiment of this application, assessing the fracturing risk of the underground gas storage facility based on monitoring data from the leak point includes: Calculate the air pressure distribution at the leak point based on the monitoring data of the leak point; The minimum principal stress and tensile strength of the surrounding rock of the underground gas storage facility are determined based on the geological survey report of the underground gas storage facility. The risk of splitting at the leak point is determined based on the gas pressure distribution, the minimum principal stress of the surrounding rock, and the tensile strength of the surrounding rock.

[0086] In this embodiment, assuming that a crack forms at the damage site, the air pressure distribution within the crack can be calculated based on the monitoring data at that site. Based on the conditions for the occurrence of rock splitting, it can be determined whether the air pressure at the damage site exceeds the sum of the minimum principal stress and tensile strength of the surrounding rock to assess the splitting risk. By determining the air pressure distribution at the leak point, the risk of splitting at the leak point can be assessed from the perspective of the coupling relationship between air pressure during operation and rock mechanics.

[0087] Specifically, the gas pressure distribution at the leak point can be calculated based on the monitoring data. Then, the minimum principal stress and tensile strength of the surrounding rock of the underground gas storage facility are determined based on the geological survey report of the underground gas storage facility. Based on the gas pressure distribution, minimum principal stress, and tensile strength of the surrounding rock, the risk of splitting at the leak point is judged from the perspective of the coupling relationship between gas pressure and rock mechanics during operation.

[0088] In one embodiment of this application, calculating the air pressure distribution at the leak point based on monitoring data of the leak point includes: The air pressure distribution at the leak point is determined based on the preset crack length at the leak point and the tail pressure at the leak point in the monitoring data. The formula for the air pressure distribution is as follows:

[0089] in: The pressure at the leak point; This represents the gas pressure distribution along coordinate x within a pre-defined crack at the leak point, where x is the length along the pre-defined crack. Spatial coordinates of direction; The tail end pressure of the pre-set crack is used in the monitoring data.

[0090] In practical implementation, assuming the longitudinal crack at the damaged area has a length of l and an opening of b, and the airflow within the crack satisfies one-dimensional steady-state flow, the pressure drop can be simplified to linear, and the expression for the air pressure distribution can be defined as:

[0091] in: The pressure at the leak point; This represents the gas pressure distribution along coordinate x within a pre-defined crack at the leak point, where x is the length along the pre-defined crack. Spatial coordinates of direction; The tail end pressure of the pre-set crack is used in the monitoring data.

[0092] In one embodiment of this application, determining whether there is a risk of splitting at the gas leakage point based on the gas pressure distribution, the minimum principal stress of the surrounding rock, and the tensile strength of the surrounding rock includes: The pressure at the leak point is determined by iterating the pressure distribution under the mass conservation condition. Determine whether the pressure at the fracture site is greater than the sum of the minimum principal stress of the surrounding rock and the tensile strength of the surrounding rock according to the judgment formula; If the pressure at the breach is greater than the sum of the minimum principal stress of the surrounding rock and the tensile strength of the surrounding rock, the leak point is at risk of splitting. The formula for determining the risk of splitting is as follows:

[0093] in: The pressure at the leak point; This represents the minimum principal stress of the surrounding rock. It represents the tensile strength of the surrounding rock.

[0094] In this embodiment, after determining the expression for the pressure distribution, the airtightness is calculated by combining the mass conservation condition and the ideal gas law, and the pressure at the rupture point is solved iteratively. The iterative solution steps are as follows: Step A1, Initial Assumptions: Assume the pressure at the break point during the initial iteration. Set the air pressure inside the storage room , that is ; Step A2: Solve for the pressure distribution using the expression for pressure distribution to obtain... ; Step A3: Calculate the flow velocity and flow rate at the crack outlet using the following formulas:

[0095]

[0096] Step A4: Update the fracture outlet pressure based on the calculated fracture outlet velocity. The updated fracture outlet pressure is expressed as follows:

[0097] Step A5: Repeat the iteration until p0 converges. The convergence criterion is: if If the result is positive, then the circuit is considered to have converged; otherwise, return to step A2.

[0098] in, The initial guess for the pressure at the break point in the 0th iteration; This refers to the average air pressure inside the storage facility, also known as the air pressure inside the storage facility. The pressure at the break point is obtained in the nth iteration; The pressure distribution along the crack at the damaged area is obtained in the nth iteration; The average gas velocity inside the crack is obtained in the nth iteration. The equivalent seepage / conductivity coefficient of the crack is obtained by experimental calibration based on crack geometric aperture and material parameters. The crack leakage volume flow rate is obtained in the nth iteration; ε is the pressure at the break point in the next iteration; ε is the convergence threshold.

[0099] Then, the pressure at the rupture point is determined according to the judgment formula to see if it is greater than the sum of the minimum principal stress of the surrounding rock and the tensile strength of the surrounding rock. If the pressure at the rupture point is greater than the sum of the minimum principal stress of the surrounding rock and the tensile strength of the surrounding rock, the leak point is considered to have a risk of splitting.

[0100] In practical implementation, the formula for determining the risk of splitting is as follows:

[0101] in: The pressure at the leak point; The minimum principal stress of the surrounding rock is derived from the geostress calculation in the geological exploration report; This represents the tensile strength of the surrounding rock, derived from rock sample test values ​​in the geological exploration report. It is obtained through monitoring... , The risk of splitting can be determined by comparing it with T.

[0102] Optionally, this embodiment can also be based on the pressure at the break point obtained through iteration. Risk classification of leak points, in Greater than or equal to At that time, it was determined to be high-risk; Greater than or equal to and less than If the risk level is low, the facility is classified as medium risk. Following this, appropriate measures are taken based on the risk classification, such as reducing pressure within the storage facility, increasing monitoring frequency, or immediately shutting it down for maintenance.

[0103] This embodiment of the method for monitoring gas leaks and assessing fracture risks in underground gas storage facilities includes: acquiring monitoring data of the underground gas storage facility; determining the leakage volume and environmental characteristic matrix of the underground gas storage facility based on the monitoring data; monitoring the leakage volume and the changing trends of the monitoring data to determine the type of leakage; locating the leak point of the underground gas storage facility based on the environmental characteristic matrix and monitoring data; assessing the fracture risk of the underground gas storage facility based on the monitoring data of the leak point; and generating an assessment report based on the assessment results of the leakage type and fracture risk. By determining the leakage type and assessing the fracture risk of the underground gas storage facility based on the monitoring data of the leak point, permeation and damage can be distinguished, enabling precise location of damage and subsequent fracture risk assessment.

[0104] It should be noted that, for the sake of simplicity, the method embodiments are all described as a series of actions. However, those skilled in the art should understand that the embodiments of this application are not limited to the described order of actions, because according to the embodiments of this application, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also understand that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily required by the embodiments of this application.

[0105] Reference Figure 2 The diagram shows a structural schematic of an underground gas storage leakage monitoring and fracturing risk assessment device provided in an embodiment of this application, which may specifically include the following: The data acquisition module 201 is used to acquire monitoring data of the underground gas storage facility, the monitoring data including: internal monitoring data and external monitoring data; Data processing module 202 is used to determine the leakage amount and environmental characteristic matrix of the underground gas storage based on the monitoring data; The gas leakage type determination module 203 is used to monitor the underground gas storage based on the gas leakage amount and the changing trend of the monitoring data, and to determine the gas leakage type of the underground gas storage. The leak location module 204 is used to locate the leak point of the underground gas storage based on the environmental feature matrix and the monitoring data. The splitting risk assessment module 205 is used to assess the splitting risk of the underground gas storage facility based on the monitoring data of the leak point. The assessment report generation module 206 is used to generate an assessment report based on the assessment results of the gas leakage type and the splitting risk.

[0106] In one embodiment of this application, the monitoring data includes at least: gas data, flow rate data, pressure data, and material data of the underground gas storage facility; the leakage amount includes: a first leakage amount and a second leakage amount; the data processing module 202 includes: The first leakage determination submodule is used to calculate the first leakage within a preset time range based on the gas data, the flow data, and the pressure data; the first leakage represents the actual leakage of the underground gas storage facility. The second leakage determination submodule is used to calculate the second leakage amount using Darcy's law based on the pressure data and the material data; the second leakage amount represents the theoretical leakage amount calculated based on the materials of the underground gas storage tank. The environmental feature matrix determination submodule is used to extract the acoustic feature values, temperature feature values, and pressure feature values ​​of the monitoring data to construct an environmental feature matrix.

[0107] In one embodiment of this application, the first leakage determination submodule includes: The cumulative leakage mass calculation unit is used to calculate the cumulative leakage mass within a preset time range based on the gas data, the flow data, and the pressure data using the ideal gas law and the flow difference method. The first leakage calculation unit is used to calculate the first leakage amount based on the cumulative leakage mass. The formula for calculating the first leakage mass is as follows:

[0108]

[0109] Wherein, P( (time) Average gas storage pressure in underground gas storage facilities; T( (time) The average temperature inside the underground gas storage facility; V is the volume of the underground gas storage facility; R air is the specific gas constant of air; m leak (t) The cumulative leakage mass up to time t; The starting time; m( )for The initial gas mass in the underground gas storage facility at any given time; This refers to the mass flow rate entering the gas storage tank through the intake pipe. This refers to the mass flow rate of gas leaving the underground gas storage facility through the outlet pipe. P(t) represents the net mass of gas injected during the time interval; P(t) represents the average gas pressure in the underground gas storage at time t; and T(t) represents the average temperature in the underground gas storage at time t. The formula for calculating the first leakage volume is as follows:

[0110] Among them: Q leak ( (time) The first leakage volume of the underground gas storage facility, that is, the cumulative actual leakage volume at time t; m leak (t) represents the first leakage mass up to time t, which is also the cumulative actual leakage mass; air ( Let P(t) be the air density at time t, calculated based on the average gas pressure P(t) and the average temperature T(t) in the underground gas storage at time t.

[0111] In one embodiment of this application, the second leakage determination submodule includes: A permeability calculation unit is used to determine the permeability of the underground gas storage tank based on the material data. The second leakage calculation unit is used to calculate the second leakage based on the permeability and the material data using Darcy's law. The formula for calculating the second leakage amount is as follows:

[0112] Where: k is the permeability, determined by material testing; L is the thickness of the sealing layer; A is the permeability area, which is also the inner surface area of ​​the underground gas storage facility; The pressure difference between the pressure inside the underground gas storage facility and the external pressure. This refers to the dynamic viscosity of the gas.

[0113] In one embodiment of this application, the changing characteristic trends include: acoustic characteristics, temperature change trends, pressure change trends, and strain trends; the leakage type determination module 203 includes: The permeability ratio calculation submodule is used to calculate the permeability ratio based on the first leakage rate and the second leakage rate. The gas leakage type determination submodule is used to determine the gas leakage type of the underground gas storage facility based on the permeability ratio, the acoustic characteristics, the temperature change trend, the pressure change trend, and the strain trend.

[0114] In one embodiment of this application, the gas leakage type determination submodule includes: The gas leakage type determination unit is used to determine the gas leakage type of the underground gas storage facility as a rupture leakage when the permeability ratio is greater than or equal to the permeability threshold, and the acoustic characteristics have preset frequency band energy, the temperature change trend and the pressure change trend have local fluctuations, and the strain trend is greater than or equal to the strain trend threshold; otherwise, the gas leakage type of the underground gas storage facility is determined to be a permeation leakage.

[0115] In one embodiment of this application, the leak location module 204 includes: The confidence calculation submodule is used to calculate the confidence level of the monitoring points based on the environmental feature matrix and the monitoring data; The leak point detection submodule is used to determine the monitoring point as a leak point when the confidence level is less than or equal to the confidence level threshold. The positioning submodule is used to locate the leak point based on the monitoring data, the sensor number corresponding to the monitoring data, and the similarity between the sensors.

[0116] In one embodiment of this application, the confidence calculation submodule includes: The variance calculation unit is used to calculate the variance of each monitoring point based on the environmental feature matrix and the eigenvalues ​​of the monitoring data. A confidence calculation unit is used to determine the confidence level of each monitoring point based on the variance; The confidence level is calculated using the following formula:

[0117] in: Let i be the confidence level of monitoring point i; The environmental feature matrix for monitoring point i; Let i be the acoustic characteristic value of the monitoring point i; The temperature characteristic value of monitoring point i; The pressure characteristic value at monitoring point i; the variance vector Var( ) represents the variance of the j-th feature component in the environmental feature matrix within the monitoring window.

[0118] In one embodiment of this application, the positioning submodule includes: The similarity calculation unit is used to calculate the similarity between data from different sensors based on the monitoring data collected by different sensors. The positioning unit is used to locate the leak point based on the time delay corresponding to the similarity that meets preset conditions; The formula for calculating the similarity is as follows:

[0119] in: (τ) is the normalized cross-correlation function of sensor i and sensor j, reflecting the similarity of the pressure waveforms of sensor i and sensor j under time delay τ; i and j are the sensor numbers. (t) represents the pressure value of sensor i at time t; (t) represents the pressure value of sensor j at time t; Let be the average pressure value of sensor i within the time interval [t0, t0+τ]. These are the average pressure values ​​of sensor j within time [t0, t0+τ], respectively; For monitoring window time.

[0120] In one embodiment of this application, the splitting risk assessment module 205 includes: The air pressure distribution calculation submodule is used to calculate the air pressure distribution at the leak point based on the monitoring data of the leak point. The stress and tensile strength determination submodule is used to determine the minimum principal stress and tensile strength of the surrounding rock of the underground gas storage facility based on the geological survey report of the underground gas storage facility. The splitting risk assessment submodule is used to determine whether there is a splitting risk at the gas leakage point based on the gas pressure distribution, the minimum principal stress of the surrounding rock, and the tensile strength of the surrounding rock.

[0121] In one embodiment of this application, the air pressure distribution calculation submodule includes: The air pressure distribution calculation unit is used to determine the air pressure distribution at the leak point based on the preset crack length of the leak point and the tail pressure of the leak point in the monitoring data. The formula for the air pressure distribution is as follows:

[0122] in: The pressure at the leak point; This represents the gas pressure distribution along coordinate x within a pre-defined crack at the leak point, where x is the length along the pre-defined crack. Spatial coordinates of direction; The tail end pressure of the pre-set crack is used in the monitoring data.

[0123] In one embodiment of this application, the splitting risk assessment submodule includes: The rupture pressure calculation unit is used to iterate the gas pressure distribution through the mass conservation condition to determine the rupture pressure at the leak point. The tensile strength determination unit is used to determine, according to the determination formula, whether the pressure at the break point is greater than the sum of the minimum principal stress of the surrounding rock and the tensile strength of the surrounding rock; A splitting risk assessment unit is used to determine that the air leakage point has a splitting risk when the pressure at the breach is greater than the sum of the minimum principal stress of the surrounding rock and the tensile strength of the surrounding rock. The formula for determining the risk of splitting is as follows:

[0124] in: The pressure at the leak point; This represents the minimum principal stress of the surrounding rock. It represents the tensile strength of the surrounding rock.

[0125] As the apparatus embodiment is basically similar to the method embodiment, it is described in a relatively simple manner. For relevant details, please refer to the description of the method embodiment.

[0126] like Figure 3 As shown, in another embodiment provided in this application, an electronic device 300 is also provided, including a memory 310 and a processor 320. The memory 310 and the processor 320 are connected via a bus for communication. The memory 310 stores a computer program, which can run on the processor 320 to implement the above steps.

[0127] like Figure 4 As shown, in another embodiment provided in this application, a computer-readable storage medium 401 is also provided, which stores a computer program that implements the methods described in the above embodiments when executed by a processor.

[0128] Those skilled in the art will understand that embodiments of this application can be provided as methods, apparatus, or computer program products. Therefore, embodiments of this application can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects. Furthermore, embodiments of this application can take the form of computer program products implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0129] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended content is intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present invention.

[0130] Those skilled in the art will understand that embodiments of this application can be provided as methods, apparatus, or computer program products. Therefore, embodiments of this application can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects. Furthermore, embodiments of this application can take the form of computer program products implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0131] This application describes embodiments with reference to flowchart illustrations and / or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0132] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0133] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal equipment, causing a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0134] Although preferred embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended content is intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of this application.

[0135] Finally, it should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties. Furthermore, the collection, use and processing of the relevant data must comply with the relevant laws, regulations and standards of the relevant countries and regions, and corresponding operation portals are provided for users to choose to authorize or refuse.

[0136] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0137] The above provides a detailed description of a method for monitoring gas leakage and assessing fracturing risk in an underground gas storage facility. Specific examples have been used to illustrate the principles and implementation methods of the invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the invention. At the same time, those skilled in the art will recognize that there will be changes in the specific implementation methods and application scope based on the ideas of the invention. Therefore, the content of this specification should not be construed as a limitation of the invention.

Claims

1. A method for monitoring gas leakage and assessing fracturing risk in an underground gas storage facility, characterized in that, The method includes: Obtain monitoring data from underground gas storage facilities; The leakage rate and environmental characteristic matrix of the underground gas storage facility are determined based on the monitoring data. Based on the leakage volume and the changing characteristics and trends of the monitoring data, the underground gas storage facility is monitored for leakage to determine the type of leakage. The leak point of the underground gas storage is located based on the environmental feature matrix and the monitoring data; The risk of fracturing in the underground gas storage facility is assessed based on the monitoring data of the leak points. An assessment report is generated based on the assessment results of the gas leak type and the splitting risk.

2. The method according to claim 1, characterized in that, The monitoring data includes at least: gas data, flow rate data, pressure data, and material data of the underground gas storage facility; the leakage amount includes: a first leakage amount and a second leakage amount; The process of determining the leakage rate and environmental characteristic matrix of the underground gas storage facility based on the monitoring data includes: The first leakage amount within a preset time range is calculated based on the gas data, the flow rate data, and the pressure data; the first leakage amount represents the actual leakage amount of the underground gas storage facility. The second leakage rate is calculated using Darcy's law based on the pressure data and the material data; the second leakage rate represents the theoretical leakage rate calculated based on the materials of the underground gas storage facility. The acoustic, temperature, and pressure features of the monitoring data are extracted to construct an environmental feature matrix.

3. The method according to claim 2, characterized in that, The calculation of the first leakage within a preset time range based on the gas data, the flow rate data, and the pressure data includes: The cumulative leakage mass within a preset time range is calculated using the ideal gas law and the flow difference method based on the gas data, the flow data, and the pressure data. Calculate the first leakage amount based on the cumulative leakage mass; The formula for calculating the first leakage mass is as follows: Wherein, P( (time) Average gas storage pressure in underground gas storage facilities; T( (time) The average temperature inside the underground gas storage facility; V is the volume of the underground gas storage facility; R air is the specific gas constant of air; m leak (t) The cumulative leakage mass up to time t; The starting time; m( )for The initial gas mass in the underground gas storage facility at any given time; This refers to the mass flow rate entering the gas storage tank through the intake pipe. This refers to the mass flow rate of gas leaving the underground gas storage facility through the outlet pipe. P(t) represents the net mass of gas injected during the time interval; P(t) represents the average gas pressure in the underground gas storage at time t; and T(t) represents the average temperature in the underground gas storage at time t. The formula for calculating the first leakage volume is as follows: Among them: Q leak ( (time) The first leakage volume of the underground gas storage facility, that is, the cumulative actual leakage volume at time t; m leak (t) represents the first leakage mass up to time t, which is also the cumulative actual leakage mass; air ( Let P(t) be the air density at time t, calculated based on the average gas pressure P(t) and the average temperature T(t) in the underground gas storage at time t.

4. The method according to claim 2, characterized in that, The calculation of the second leakage rate using Darcy's law based on the pressure data and the material data includes: The permeability of the underground gas storage facility is determined based on the material data. The second leakage rate is calculated using Darcy's law based on the permeability and the material data. The formula for calculating the second leakage amount is as follows: Where: k is the permeability, determined by material testing; L is the thickness of the sealing layer; A is the permeability area, which is also the inner surface area of ​​the underground gas storage facility; The pressure difference between the pressure inside the underground gas storage facility and the external pressure. This refers to the dynamic viscosity of the gas.

5. The method according to claim 1, characterized in that, The changing characteristics include: acoustic characteristics, temperature change trends, pressure change trends, and strain trends; The process of monitoring the underground gas storage facility for leaks based on the leakage volume and the changing trends of the monitoring data, and determining the type of leak, includes: Calculate the permeability ratio based on the first and second leakage rates; The type of gas leakage in the underground gas storage facility is determined based on the permeability ratio, the acoustic characteristics, the temperature change trend, the pressure change trend, and the strain trend.

6. The method according to claim 5, characterized in that, The method of determining the type of gas leakage in the underground gas storage facility based on the permeability ratio, the acoustic characteristics, the temperature change trend, the pressure change trend, and the strain trend includes: If the permeability ratio is greater than or equal to the permeability threshold, and the acoustic characteristics have energy in a preset frequency band, the temperature change trend and the pressure change trend have local fluctuations, and the strain trend is greater than or equal to the strain trend threshold, the leakage type of the underground gas storage is a rupture leakage; otherwise, the leakage type of the underground gas storage is determined to be a permeation leakage.

7. The method according to claim 1, characterized in that, The step of locating the leak point of the underground gas storage facility based on the environmental feature matrix and the monitoring data includes: Calculate the confidence level of the monitoring points based on the environmental feature matrix and the monitoring data; If the confidence level is less than or equal to the confidence level threshold, the monitoring point is identified as a leak point; The leak point is located based on the monitoring data, the sensor number corresponding to the monitoring data, and the similarity between the sensors.

8. The method according to claim 7, characterized in that, The step of calculating the confidence level of the monitoring points based on the environmental feature matrix and the monitoring data includes: Calculate the variance of each monitoring point based on the environmental feature matrix and the eigenvalues ​​of the monitoring data; The confidence level of each monitoring point is determined based on the variance. The confidence level is calculated using the following formula: in: Let i be the confidence level of monitoring point i; The environmental feature matrix for monitoring point i; Let i be the acoustic characteristic value of the monitoring point i; The temperature characteristic value of monitoring point i; The pressure characteristic value at monitoring point i; the variance vector Var( ) represents the variance of the j-th feature component in the environmental feature matrix within the monitoring window.

9. The method according to claim 7, characterized in that, The step of locating the leak point based on the monitoring data, the sensor number corresponding to the monitoring data, and the similarity between the sensors includes: The similarity between data collected by different sensors is calculated. The leak point is located based on the time delay corresponding to the similarity that meets preset conditions; The formula for calculating the similarity is as follows: in: (τ) is the normalized cross-correlation function of sensor i and sensor j, reflecting the similarity of the pressure waveforms of sensor i and sensor j under time delay τ; i and j are the sensor numbers. (t) represents the pressure value of sensor i at time t; (t) represents the pressure value of sensor j at time t; Let be the average pressure value of sensor i within the time interval [t0, t0+τ]. These are the average pressure values ​​of sensor j within time [t0, t0+τ], respectively; For monitoring window time.

10. The method according to claim 1, characterized in that, The assessment of the fracture risk of the underground gas storage facility based on monitoring data from the leak points includes: Calculate the air pressure distribution at the leak point based on the monitoring data of the leak point; The minimum principal stress and tensile strength of the surrounding rock of the underground gas storage facility are determined based on the geological survey report of the underground gas storage facility. The risk of splitting at the leak point is determined based on the gas pressure distribution, the minimum principal stress of the surrounding rock, and the tensile strength of the surrounding rock.

11. The method according to claim 9, characterized in that, The step of calculating the air pressure distribution at the leak point based on the monitoring data of the leak point includes: The air pressure distribution at the leak point is determined based on the preset crack length at the leak point and the tail pressure at the leak point in the monitoring data. The formula for the air pressure distribution is as follows: in: The pressure at the leak point; This represents the gas pressure distribution along coordinate x within a pre-defined crack at the leak point, where x is the length along the pre-defined crack. Spatial coordinates of direction; The tail end pressure of the pre-set crack is used in the monitoring data.

12. The method according to claim 10, characterized in that, The method of determining whether there is a risk of splitting at the gas leakage point based on the gas pressure distribution, the minimum principal stress of the surrounding rock, and the tensile strength of the surrounding rock includes: The pressure at the leak point is determined by iterating the pressure distribution under the mass conservation condition. Determine whether the pressure at the fracture site is greater than the sum of the minimum principal stress of the surrounding rock and the tensile strength of the surrounding rock according to the judgment formula; If the pressure at the breach is greater than the sum of the minimum principal stress of the surrounding rock and the tensile strength of the surrounding rock, the leak point is at risk of splitting. The formula for determining the risk of splitting is as follows: in: The pressure at the leak point; This represents the minimum principal stress of the surrounding rock. It represents the tensile strength of the surrounding rock.

13. A device for monitoring gas leakage and assessing fracturing risk in an underground gas storage facility, characterized in that, The device includes: The data acquisition module is used to acquire monitoring data of the underground gas storage facility, including internal monitoring data and external monitoring data. The data processing module is used to determine the leakage amount and environmental characteristic matrix of the underground gas storage facility based on the monitoring data. The gas leakage type determination module is used to monitor the underground gas storage facility based on the gas leakage amount and the changing trend of the monitoring data, and to determine the gas leakage type of the underground gas storage facility. A leak location module is used to locate the leak point of the underground gas storage facility based on the environmental feature matrix and the monitoring data. The splitting risk assessment module is used to assess the splitting risk of the underground gas storage facility based on the monitoring data of the leak point.

14. An electronic device, characterized in that, include: A memory, a processor, and a computer program stored on the memory, wherein the processor executes the computer program to implement the method of any one of claims 1-12.

15. A computer-readable storage medium, characterized in that, A computer program is stored on the computer-readable storage medium, which, when executed by a processor, implements the method as described in any one of claims 1-12.

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