Real-time monitoring method and system for gas leakage of sealing material of underground high-pressure gas storage

Abstract

The invention discloses an underground high-pressure gas storage sealing material gas leakage real-time monitoring method and system, and the method and system achieve the real-time monitoring of the leakage of high-pressure gas during the operation of an underground high-pressure gas storage sealing steel plate through distributed optical fiber temperature measurement, and can monitor all hidden danger points where the leakage of the high-pressure gas occurs. And the abnormal temperature change position can be quickly and accurately positioned, and long-distance effective monitoring in a complex environment is realized. Compared with an existing monitoring means, the method and system have obvious advantages in the aspects of real-time performance, accuracy, effectiveness, comprehensiveness and the like of high-pressure gas leakage monitoring, and have high popularization significance.

Description

Technical Field

[0001] This invention relates to a method and system for real-time monitoring of gas leakage in the sealing material of an underground high-pressure gas storage facility, belonging to the field of compressed air energy storage. Background Technology

[0002] Compressed air energy storage (CASS) is a technology that uses air as an energy storage medium to circulate and release energy. It typically functions as a grid regulator, providing peak shaving, valley filling, frequency regulation, and emergency backup. It is a promising large-scale physical energy storage method. Currently, salt caverns or newly excavated underground chambers are commonly used as underground gas storage facilities. Due to the limited distribution area of ​​salt caverns and strict requirements on their shape and geological stratification, the number of salt caverns is relatively small. Conversely, newly excavated underground gas storage facilities can be built in widely distributed hard rock strata, offering greater site selection flexibility and the potential for large-scale deployment. This is also the main development direction for compressed air energy storage projects.

[0003] Newly excavated underground high-pressure gas storage facilities are a crucial component of compressed air energy storage projects, and their safe and effective operation directly impacts the project's efficiency and even its success or failure. Sealing design is a key aspect of underground gas storage facilities, and high-strength steel plates are commonly used as the sealing material. Dynamically, in real-time, and continuously monitoring the sealing effect of the steel plates under the cyclical loads of gas filling and discharging during operation is essential. Generally, gas leakage monitoring projects use the pressure difference between the inside and outside of the sealing material. However, due to the short filling and discharging cycle intervals in compressed air energy storage projects and the fact that the sealing steel plates are not exposed to air, this method is unsuitable for real-time monitoring. Therefore, a new monitoring method is urgently needed to conveniently, quickly, and effectively address the problem of real-time, reasonable, and effective monitoring of high-pressure gas leakage in sealing steel plates under conditions unaffected by external environmental factors. Summary of the Invention

[0004] The present invention aims to provide a method and system for real-time monitoring of gas leakage in sealing materials of underground high-pressure gas storage facilities. The method and system can monitor the high-pressure gas leakage of sealing materials in a timely, reasonable and effective manner, providing support for the safe and effective operation of underground high-pressure gas storage facilities.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is: a method for monitoring gas leakage of sealing materials in underground high-pressure gas storage facilities, the method comprising: S1. The server obtains the existing temperature duration curve of the inflation / deflation cycle process; S2, In the current inflation / deflation cycle, if Then the server determines the corresponding first Gas leakage was detected at one of the measuring points; in, , The number of measurement points, For the first The measurement deviation of a measuring point at a certain time point , This represents the number of consecutive temperature measurements in the current charge / discharge cycle. For the first The first measuring point The measurement deviation value of this measurement. , For the first The first measuring point The temperature value was measured once. For the first The average temperature of each measuring point at the corresponding time point in the existing temperature duration curve; , The system accuracy of a distributed fiber optic temperature demodulator is defined as the deviation between the measured temperature value and the actual temperature value. For the first The arithmetic mean of the standard deviations of the measurements at each measuring point. , For the first The maximum value among continuously measured temperature values ​​at each measuring point For the first The minimum value among continuously measured temperature values ​​at each measuring point. This is the range coefficient.

[0006] The above scheme, through real-time monitoring of gas leakage during the operation of sealing materials, can detect all potential sources of high-pressure gas leakage, quickly and accurately locate abnormal temperature changes, and achieve effective monitoring in complex environments and over long distances. The distributed fiber optic temperature demodulator [Reference: Han Yongwen, Hao Wenjie, Zhang Linxing, Zhang Xiaofei, Lü Zhonghu, Research on Distributed Fiber Optic Temperature Measurement System Based on Raman Scattering Principle, Semiconductor Optoelectronics 2013, DOI: CNKI:SUN:BDTG.0.2013-02-043] utilizes optical time-domain reflectometry and spontaneous Raman scattering effect to obtain temperature information by analyzing the backscattered light generated when laser propagates in an optical fiber.

[0007] According to embodiments of the present invention, the present invention can be further optimized, and the optimized technical solution is as follows:

[0008] In one preferred embodiment, the process of obtaining the existing temperature duration curve of the charging and discharging cycle in S1 specifically includes: A1. During the charging and discharging cycle, the server periodically sends measurement instructions to the distributed fiber optic temperature demodulator; the measurement instructions include the number of measurement groups for a single charging and discharging cycle and the number of times the temperature is continuously measured in each measurement group; A2. In each measurement group, the distributed fiber optic temperature demodulator emits a laser beam at the beginning of the temperature sensing optical cable. The optical signals of all measuring points are transmitted through the temperature sensing optical cable and collected at the end of the temperature sensing optical cable by the distributed fiber optic temperature demodulator for analog-to-digital conversion to obtain the temperature values ​​of all measuring points in each measurement group. A3. Repeat step A2 to obtain the temperature values ​​of all measuring points in all groups of a single charge-discharge cycle, and transmit them to the server to generate the temperature duration curves of all measuring points.

[0009] Temperature-sensing optical cable [Reference: Xu Hong, Feng Weiyi, Zhao Xia, Huang Xiaowei, Liu Lihua, Research on Material Characteristics of Special Temperature-Sensing Optical Cable for Leak Detection of Normal Temperature Transmission Pipelines, Science & Technology Information 2020, DOI: 10.16661 / j.cnki.1672-3791.2002-1015-3412], also known as temperature-sensing optical cable or temperature-measuring optical cable, is a special optical cable integrating fiber optic sensing technology and temperature-sensing materials. Its main function is to convert temperature signals into electrical signals through optical fibers, realizing long-distance, high-precision temperature monitoring. It utilizes optical fibers as sensors, based on the relationship between the scattering effect of light in the optical fiber and temperature, combined with optical time-domain reflectometry (OTDR) technology to locate and measure temperature changes.

[0010] Based on the same concept, the present invention also provides a method for monitoring gas leakage in the sealing material of an underground high-pressure gas storage facility, the method comprising: during the current filling and discharging cycle, if the... If the temperature difference between the measuring point and the inner side of the corresponding sealing material is less than a first threshold, then the server determines that the temperature difference is less than a first threshold. Gas leakage was detected at one measuring point; the value of the first threshold was set according to the sealing degree of the sealing material.

[0011] Based on the same concept, the present invention also provides a gas leakage monitoring system for sealing materials in underground high-pressure gas storage facilities. The system includes a temperature-sensing optical cable, a distributed fiber optic temperature demodulator, and a server. The temperature-sensing optical cable is tightly attached to the outer surface of the sealing material and arranged in a ring along the longitudinal axis of the underground high-pressure gas storage facility. Both its first and last ends are connected to the distributed fiber optic temperature demodulator for transmitting optical signals from the measuring points. These optical signals are used for signal transmission and temperature measurement. The distributed fiber optic temperature demodulator is used to acquire and convert the optical signals from analog to digital. The distributed fiber optic temperature demodulator is connected to the server. The server processes the converted optical signals and determines the gas leakage at the measuring points according to the aforementioned method for monitoring gas leakage in sealing materials in underground high-pressure gas storage facilities. The server also includes a database for storing temperature history curves.

[0012] The above solution uses distributed fiber optic temperature measurement to achieve real-time monitoring of high-pressure gas leakage during the operation of the sealing steel plate of the underground high-pressure gas storage facility. It can detect all potential points of high-pressure gas leakage and quickly and accurately locate abnormal temperature changes, enabling effective monitoring in complex environments and over long distances.

[0013] In one preferred embodiment, the spacing between the circular arrangement of the optical cables is 1.5m to 3.0m. This method allows for precise location of gas leakage points in the sealing steel plate.

[0014] Compared with existing technologies, the beneficial effects of this invention are as follows: This invention provides a method and system for real-time monitoring of gas leakage in the sealing materials of underground high-pressure gas storage facilities. It employs distributed fiber optic temperature measurement to achieve real-time monitoring of high-pressure gas leakage during the operation of the sealing materials. This allows for the detection of all potential sources of high-pressure gas leakage and the rapid and accurate location of abnormal temperature changes, enabling effective monitoring in complex environments and over long distances. Compared with existing monitoring methods, this method and system possess significant advantages in terms of real-time performance, accuracy, effectiveness, and comprehensiveness in high-pressure gas leakage monitoring, and therefore have strong potential for widespread application. Attached Figure Description

[0015] Figure 1 This is a schematic diagram illustrating the working principle of optical cable temperature measurement. Figure 2 This is a schematic diagram of optical cable temperature measurement and positioning; Figure 3 This is a schematic diagram of the DTS system layout according to an embodiment of the present invention; Figure 4 This is a flowchart of the DTS system workflow according to an embodiment of the present invention; Figure 5 This is a temperature duration curve diagram of another embodiment of the present invention. Detailed Implementation

[0016] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0017] Example 1

[0018] Newly excavated underground high-pressure gas storage facilities are typically located in hard rock areas with relatively good surrounding rock integrity. High-strength steel plates are used as the sealing material for the underground gas storage facility, and high-grade concrete is backfilled between the surrounding rock and the steel plates, forming a joint load-bearing structure. The integrity and airtightness of the sealing steel plates are crucial to ensuring the safe and effective operation of the underground gas storage facility. The inner side of the steel plate is in direct contact with compressed air and must withstand the impact of high-pressure air and the additional temperature stress caused by large temperature differences and alternating hot and cold cycles. The outer side must withstand the continuous pressure of groundwater. Under the combined action of internal and external forces, the steel plate may fail, resulting in high-pressure gas leakage. In order to locate the location of gas leakage caused by steel plate failure in real time and accurately, a DTS (Distributed Temperature Sensing) system needs to be installed on the outside of the high-strength steel plate to achieve automated observation, so as to provide timely feedback and early warning.

[0019] Real-time monitoring of gas leakage through the sealing steel plates of high-pressure gas storage tanks using distributed optical fiber temperature sensing works on the principle that the distributed optical fiber temperature sensing system is an optical time-domain temperature monitoring system. This system uses a light pulse of a specific frequency to irradiate the glass core within the optical fiber. As the light pulse travels along the fiber's glass core, various types of radiation scattering occur, such as Rayleigh scattering, Brillouin scattering, and Raman scattering. Among these, Raman scattering is related to the thermal vibrations of fiber molecules and is therefore the most sensitive to temperature, making it suitable for temperature measurement. Figure 1 The diagram shown illustrates the working principle of optical cable temperature measurement.

[0020] The DTS system is based on the principle of Raman scattering in light and combines it with optical time-domain reflectometry (OTDR) to continuously measure the temperature at any point along an optical fiber. In Raman scattering, light with a frequency lower than the incident light frequency is called Stokes light, and light with a frequency higher than the incident light frequency is called anti-Stokes light. The spectral distribution of Stokes light and anti-Stokes light is symmetrical. The intensity of Stokes light is minimally affected by temperature and can be ignored, while the intensity of anti-Stokes light is temperature-sensitive and modulated by temperature; the higher the temperature, the higher the intensity of the scattered light.

[0021] Two key technologies of the DTS system are the Raman scattering effect for temperature measurement and the optical time domain reflectometry technology for positioning. Usually, the anti-Stokes light serves as the signal channel and the Stokes light serves as the reference channel. The intensity ratio between the two lights and the temperature can be fitted into a certain functional relationship. By detecting the light intensity ratio between the two, the temperature can be demodulated. In optical time domain reflectometry, using the OTDR technology, based on the transmission rate of the optical pulse in the optical fiber and the time difference between the incident light and the backward Raman scattered light (including Stokes light and anti-Stokes light), different temperature points can be positioned, as Figure 2 shown, where t is the time for the incident light to travel to and from the measurement point, and L is the distance between the incident light and the measurement point.

[0022] A real-time monitoring system for gas leakage of a sealing material in an underground high-pressure gas storage proposed in Embodiment 1 includes a hardware part and a software part; the hardware part includes a temperature sensing optical cable, a distributed optical fiber temperature measurement demodulator, and a data server. The temperature sensing optical cable serves both as a signal conduction medium and as a sensing medium for temperature measurement. Laying the temperature sensing optical cable on the outer surface of the sealing steel plate is equivalent to the sensing neural network of the DTS system; the head and tail ends of the temperature sensing optical cable are connected to the distributed optical fiber temperature measurement demodulator, which is equivalent to the sensing brain of the DTS system and interprets (collects and performs analog-to-digital conversion) the transmitted optical signal. After being interpreted by the distributed optical fiber temperature measurement demodulator, the optical signal is connected to the data server for monitoring, and analysis software supporting the DTS system is installed in the data server. The analysis software includes functional modules such as parameter configuration, temperature measurement, data processing and analysis, data storage and query, temperature anomaly alarm, mapping and display, result calling and export, printing, etc. Through the software, the operating state of the sealing steel plate can be analyzed, fed back, and warned.

[0023] The temperature sensing optical cable adopts an embedded installation scheme. To accurately measure the temperature of the outer wall of the sealing steel plate, the sensing optical cable must be a single, continuous piece, arranged in a ring along the longitudinal axis of the gas storage tank, closely attached to the outer side of the sealing steel plate. The ring spacing is generally 1.5m to 3.0m to accurately locate the gas leakage point of the sealing steel plate. Both ends are connected to a fiber optic temperature demodulator installed outside the underground gas storage tank. The position of the fiber optic rings avoids the weld seams of the steel plate rings, and the optical cables between each ring are connected at the top arch position to reduce interference between the fiber optic installation and the steel plate construction, and to better protect the optical fiber. Depending on the transmission distance of the signal under test, single-mode multi-core fiber or multi-mode multi-core fiber should be selected for the optical cable. For multi-mode multi-core fiber, 62.5 / 125 and 50 / 125 specifications (for longer distances) should be selected based on the transmission distance. The number of cores should not be less than twice the number of signals to be transmitted, and approximately 20% of the channels should be reserved as backup. This dual protection elevates temperature sensing to a reliable level, eliminating the impact of daily single-point failures, coping with sudden risks and long-term losses, and reserving space for future upgrades, achieving uninterrupted monitoring, no performance degradation, and low-cost expansion. Flexible, bendable, and durable armored temperature sensing optical cables are recommended to resist potential impact damage during construction and corrosion from the operating environment. They should be laid tightly against the outer surface of the sealed steel plate using an adhesive method, ensuring a close bond and good deformation coordination.

[0024] The fiber optic temperature demodulator is deployed at the monitoring station. It measures the temperature at various points (measuring points) along a calibrated optical cable by emitting a laser beam at the head end, transmitting the measured temperature as an optical signal to the demodulator at the tail end. The fiber optic temperature demodulator employs a single detector design, operating under constant temperature and pressure, avoiding measurement deviations caused by component inconsistencies, resulting in higher temperature measurement accuracy and better stability. Through the acquisition and analog-to-digital conversion of the large amount of data generated during operation, it enables the detection of temperature anomalies in small areas. The measuring point is the basic monitoring unit in the DTS system. By analyzing the propagation characteristics of the optical signal in the fiber (such as Raman scattering and Brillouin scattering), continuous temperature measurement along the length of the optical cable is achieved. Each measuring point corresponds to a physical location on the optical cable, and the DTS system can accurately obtain the temperature value at that point. Figure 4 The diagram shown illustrates the workflow of the DTS system. DTS systems are installed at observation stations and can simultaneously monitor multiple sealing steel plates.

[0025] Example 2

[0026] This embodiment 2 provides a method for detecting gas leakage in a sealed steel plate, the method specifically including:

[0027] During a single charge / discharge cycle, the optical signals at each measuring point are decoded by a fiber optic temperature demodulator, and the monitoring results are transmitted to the server at the monitoring center to generate a temperature duration curve, such as... Figure 5 As shown.

[0028] Compared with the existing temperature history curves in the database, in different cycles, the first The measurement deviation of each measuring point at the same time point is: ,in, , This represents the number of consecutive temperature measurements in the current charge / discharge cycle. For the first The first measuring point The deviation value of the measured temperature. , For the first The first measuring point The temperature value was measured once. For the first The average temperature of each measuring point at the corresponding time point in the existing temperature duration curve; , The system accuracy of the distributed fiber optic temperature demodulator is defined as the deviation between the measured temperature value and the actual temperature value. For the first The arithmetic mean of the standard deviations of the measurements at each measuring point. , For the first The maximum value among continuously measured temperature values ​​at each measuring point For the first The minimum value among continuously measured temperature values ​​at each measuring point. The range coefficient can be obtained by looking up a table, as shown in Table 1.

[0029] Table 1 Range Coefficient Lookup Table Number of readings 2 3 4 5 6 7 8 9 C 1.13 1.69 2.06 2.33 2.53 2.70 2.85 2.97

[0030] when When this occurs, the server determines that a gas leak has occurred at the measuring point; whereby, These are the deviation control limits.

[0031] Example 3

[0032] This embodiment 3 also provides a method for detecting gas leakage in a sealing steel plate, the method specifically including:

[0033] If there is no significant difference between the temperature at the measuring point of the temperature sensing optical cable and the temperature inside the sealed steel plate at the same location and time, the server determines that there may be gas leakage at this point.

[0034] The change in the thermal conductivity thickness of the sealing steel plate during the charging and discharging operation is deduced based on thermodynamic calculation formulas, thereby verifying the operating status of the sealing steel plate: .in, This refers to the heat conduction value of the sealed steel plate. Thermal conductivity, The temperature of the inner wall of the sealed steel plate can be obtained using a high-pressure thermometer. The temperature of the optical fiber measuring point at the corresponding location on the inner wall of the sealed steel plate is measured. For heat conduction time, For contact area, This refers to the thermal conductivity thickness of the sealing steel plate. The physical thickness of the sealing steel plate is determined during installation. (The remaining text appears to be incomplete and possibly contains errors. A more accurate translation would require the full context.) The fact that the thickness is consistent with the physical thickness and remains stable indicates that the steel plate has normal heat transfer and is free from damage. If the thickness is much smaller than the physical thickness, it may indicate that the steel plate is damaged, allowing heat to be transferred directly via a short circuit without passing through the full thickness. In this case, the sealing performance of the sealing steel plate fails.

[0035] The DTS system is equipped with temperature warning thresholds, which are set with different colors such as red, orange, yellow, and green. The different colors indicate the sealing degree of the sealing steel plate. An audible and visual alarm device is connected to the server terminal. After an abnormal temperature occurs, the temperature measurement results of each measuring point will be displayed on the server screen according to the different colors, and an audible warning will be issued for the red area.

[0036] Example 4

[0037] like Figure 3 The diagram shows the layout of a DTS (Digital Transmission System) for an underground high-pressure gas storage facility in China. Two gas storage chambers are arranged in parallel, with a circular cross-section and a net diameter of 10 meters. The sealing steel plates are made of Q345R steel. The DTS system monitors high-pressure gas leakage in real time. The temperature-sensing optical cable is a single, continuous cable embedded tightly in the backfill concrete, with its ends led out from a fiber optic temperature demodulator located at the ground monitoring center. After passing through a vertical shaft, it connects the two gas storage chambers, forming a complete closed loop. The temperature-sensing optical cable is continuously arranged in a ring along the axis of the two underground gas storage facilities. 71 and 25 represent the number of cable rings, with a spacing of 1.5 meters between each ring. The rings avoid the circumferential welds of the steel plates and enter the next adjacent ring at the top arch. After connecting the two gas storage chambers, the optical cable is laid along the access hole of the connecting tunnel to the bottom of the vertical shaft and then led out to the fiber optic temperature demodulator.

[0038] During the inflation / deflation process, after the server issues a timed measurement command (interval set to 10 minutes, or other intervals longer than 1 minute), a laser beam is emitted at the beginning of the optical cable to begin measurement. Optical signals from each measurement point (1m apart) are collected and transmitted to the fiber optic temperature demodulator at the end. Each set of optical signals consists of three consecutive measurements. After decoding by the demodulator, the temperature results are imported into the server and compared with the existing temperature timeline of a normal inflation / deflation cycle. The temperatures at a certain measurement point were 67.3℃, 67.5℃, and 67.6℃ in the three consecutive measurements. The arithmetic mean of the standard deviation of the measured values ​​at this measurement point was calculated. The accuracy is 0.2℃, and the automatic measurement accuracy is [not specified]. The deviation control limit was obtained at ±0.5℃. The value is 0.53. The average temperature at this point during a normal charge / discharge cycle is 66.3℃. The difference between this measured value and the average value from the existing normal cycle is calculated to be... The value is 1.08, therefore, the following occurs. The situation indicates that a gas leak has occurred near this measuring point, requiring immediate depressurization of the high-pressure gas storage tank and repair of the sealing steel plate at the gas leak point.

[0039] This embodiment employs distributed optical fiber temperature measurement to achieve real-time monitoring of high-pressure gas leakage during the operation of the sealed steel plates in an underground high-pressure gas storage facility. It utilizes a long-distance, uninterrupted monitoring method arranged in a network, effectively meeting design and operational requirements. Compared to existing high-pressure gas leakage monitoring methods, this embodiment offers the following advantages: First, it achieves effective monitoring and transmission over long distances. The effective monitoring distance of single-mode optical fiber can reach 20km–30km, and that of multimode optical fiber reaches 3km, with no signal distortion and minimal attenuation of the optical signal intensity during transmission. Second, it enables effective monitoring and transmission in complex environments. Underground engineering projects face complex construction environments, including variable surrounding rock conditions, abundant groundwater, and electromagnetic interference. The temperature-sensing optical cable overcomes these adverse environmental factors, achieving effective monitoring of leaking gas. Third, it provides comprehensive and effective monitoring of gas leakage from the sealed steel plates. The distributed and continuous arrangement of temperature-sensing optical cables allows for comprehensive and systematic monitoring of the sealed steel plates, effectively unifying the typicality and universality of safety monitoring. It can detect all potential sources of high-pressure gas leakage and quickly and accurately locate abnormal temperature changes (temperature measurement accuracy ≤0.5℃, location accuracy reaches 0.5m level). Fourth, it enables real-time dynamic monitoring of the monitored object. Through the transmission of temperature-sensing optical cables and software analysis, the operating status of the sealed steel plates can be judged in a timely manner (response time <2s), and early warning and other feedback information can be provided. Fifth, it has strong temperature measurement adaptability and weather resistance. The temperature measurement range of the temperature-sensing optical cables is -40℃ to +120℃, with a maximum of 200℃, which matches the temperature changes during the operation of underground gas storage facilities. The non-bare fiber (armored) design is explosion-proof, chemically stable, corrosion-resistant, and does not generate pollution. Sixth, the temperature-sensing optical cables are passive monitoring instruments, requiring no power supply and generating no static electricity during measurement, making implementation and operation in underground spaces such as underground gas storage facilities safer and more convenient.

[0040] In the implementation of real-time monitoring of gas leakage in sealing materials of underground high-pressure gas storage facilities, the DTS system has unparalleled technical and management advantages in terms of real-time performance, accuracy, effectiveness, and comprehensiveness of high-pressure gas leakage monitoring. Furthermore, the signal transmission and integrated automation of fiber optic sensors are the main trends in the development of the safety monitoring industry, making it highly significant for widespread application.

[0041] The above embodiments should be understood as being used only to illustrate the present invention more clearly, and not to limit the scope of the present invention. After reading the present invention, any modifications of the present embodiments by those skilled in the art will fall within the scope defined by the appended claims.

Claims

1. A method for monitoring gas leakage in the sealing material of an underground high-pressure gas storage facility, characterized in that, The method includes: S1. The server obtains the existing temperature duration curve of the inflation / deflation cycle process; S2, In the current inflation / deflation cycle, if Then the server determines the corresponding first Gas leakage was detected at one of the measuring points; in, , The number of measurement points, For the first The measurement deviation of a measuring point at a certain time point , This represents the number of consecutive temperature measurements in the current charge / discharge cycle. For the first The first measuring point The measurement deviation value of this measurement. , For the first The first measuring point The temperature value was measured once. For the first The average temperature of each measuring point at the corresponding time point in the existing temperature duration curve; , To improve the system accuracy of the distributed fiber optic temperature demodulator. For the first The arithmetic mean of the standard deviations of the measurements at each measuring point. , For the first The maximum value among continuously measured temperature values ​​at each measuring point For the first The minimum value among continuously measured temperature values ​​at each measuring point. This is the range coefficient.

2. The method for monitoring gas leakage of sealing materials in underground high-pressure gas storage facilities according to claim 1, characterized in that, In S1, the process of obtaining the existing temperature duration curve of the charging and discharging cycle includes: A1. During the charging and discharging cycle, the server periodically sends measurement instructions to the distributed fiber optic temperature demodulator; the measurement instructions include the number of measurement groups for a single charging and discharging cycle and the number of times the temperature is continuously measured in each measurement group; A2. In each measurement group, the distributed fiber optic temperature demodulator emits a laser beam at the beginning of the temperature sensing optical cable. The optical signals of all measuring points are transmitted through the temperature sensing optical cable and collected at the end of the temperature sensing optical cable by the distributed fiber optic temperature demodulator for analog-to-digital conversion to obtain the temperature values ​​of all measuring points in each measurement group. A3. Repeat step A2 to obtain the temperature values ​​of all measuring points in all groups of a single charge-discharge cycle, and transmit them to the server to generate the temperature duration curves of all measuring points.

3. A method for monitoring gas leakage in the sealing material of an underground high-pressure gas storage facility, characterized in that, The method includes: In the current inflation / deflation cycle, if the first If the temperature difference between the measuring point and the inner side of the corresponding sealing material is less than a first threshold, then the server determines that the temperature difference is less than a first threshold. Gas leakage was detected at one measuring point; the value of the first threshold was set according to the sealing degree of the sealing material.

4. A gas leakage monitoring system for sealing materials in underground high-pressure gas storage facilities, characterized in that, The system includes a temperature sensing optical cable, a distributed optical fiber temperature demodulator, and a server; The temperature sensing optical cable is tightly attached to the outer surface of the sealing material and is arranged in a ring along the longitudinal axis of the underground high-pressure gas storage tank. Its first and last ends are connected to the distributed optical fiber temperature demodulator for transmitting optical signals at the measuring points. The optical signals are used for signal transmission and temperature measurement. The distributed optical fiber temperature demodulator is used to acquire and convert the optical signal from analog to digital, and the distributed optical fiber temperature demodulator is connected to the server. The server is used to process the optical signal after analog-to-digital conversion, and to determine the gas leakage at the measuring point using the gas leakage monitoring method for sealing materials of underground high-pressure gas storage facilities according to any one of claims 1-3. The server includes a database for storing temperature duration curves.

5. The gas leakage monitoring system for the sealing material of an underground high-pressure gas storage facility according to claim 4, characterized in that, The spacing between the circular arrangement of the optical cables is 1.5m to 3.0m.

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