Natural gas hydrogen-doped multi-scene leakage monitoring and early warning method and system and medium

Abstract

According to the natural gas hydrogen-doped multi-scene leakage monitoring and early warning method and system and the computer readable storage medium provided by the invention, through a sensor fusion technology and a self-learning mechanism, accurate identification and high-precision monitoring of leakage signals are realized, and the monitoring precision can be remarkably improved; by using the application of a deep learning early warning model and a multi-stage early warning strategy, the early warning accuracy and timeliness are improved, precious time is gained for emergency response, the early warning intelligence is enhanced, the key problems of insufficient accuracy, low early warning intelligence degree and the like of hydrogen-doped natural gas leakage monitoring in the prior art are solved, and the safety of hydrogen-doped natural gas leakage monitoring is improved. And the conveying safety of the hydrogen-doped natural gas is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of natural gas leakage monitoring, and in particular to a natural gas hydrogen-blended multi-scenario leakage monitoring and early warning method, system, and computer-readable storage medium. Background Art

[0002] With the growing global demand for low-carbon, efficient energy utilization, natural gas hydrogen blending technology is a key technology for achieving energy transition and emission reduction goals. Due to the small size, rapid diffusion rate, and flammability and explosiveness of hydrogen molecules, safety issues have become a key factor restricting its large-scale application. This has led to higher requirements for pipeline concentration monitoring, full-process leak detection, and early warning during the transportation of hydrogen-blended natural gas. While existing natural gas leak monitoring and early warning systems can address the risk of methane leaks to a certain extent, they still have significant shortcomings in monitoring accuracy and the intelligent application or expansion of early warning systems for hydrogen-blended natural gas. The limitations of existing technologies are particularly prominent under complex and variable operating conditions, such as extreme environments with hypoxia, high temperature, and high humidity. Therefore, the development of high-precision monitoring and intelligent early warning systems is crucial for improving the overall safety and emergency response capabilities of hydrogen-blended natural gas systems. Summary of the Invention

[0003] The present invention aims to provide a multi-scenario leakage monitoring and early warning method, system and computer-readable storage medium for natural gas hydrogen blending that overcome the above-mentioned problems or at least partially solve the above-mentioned problems.

[0004] To achieve the above object, the technical solution of the present invention is specifically implemented as follows:

[0005] A first aspect of the present invention provides a multi-scenario leakage monitoring and early warning method for natural gas hydrogen-blended gas, comprising:

[0006] Set up pipeline gas monitoring units, pipeline interface / valve gas concentration monitoring units, and indoor online gas leakage monitoring units according to the preset method;

[0007] obtaining first methane concentration data, first hydrogen concentration data, and pipeline pressure data output by the pipeline gas monitoring unit, calculating a pipeline hydrogen volume ratio based on the first methane concentration data and the first hydrogen concentration data, and comparing the calculated values ​​with a first methane concentration warning value, a first hydrogen concentration warning value, a first pressure warning value, and a hydrogen volume ratio warning value, respectively; and generating a first alarm message if a first preset condition is met;

[0008] obtaining second methane concentration data and second hydrogen concentration data at the pipeline interface / valve output by the pipeline interface / valve gas concentration monitoring unit, and comparing them with the second methane concentration warning value and the second hydrogen concentration warning value, and generating a second alarm message if a second preset condition is met;

[0009] Acquire methane concentration data and hydrogen concentration data output by the online monitoring unit in the gas leakage room, and calculate the leakage location based on the diffusion rate of hydrogen in the air and the diffusion rate of methane in the air;

[0010] Establish a calculation model for the dynamic explosion limit of hydrogen-methane;

[0011] Different levels of early warning signals are triggered according to the leakage and spread conditions.

[0012] Optionally, the setting of the pipeline gas monitoring unit in a preset manner includes:

[0013] The pipeline gas monitoring unit is configured as follows: a monitoring hole is opened on the pipeline, a monitoring space is set at the monitoring hole, a first solenoid valve and a valve controlled by the first solenoid valve, a second solenoid valve and a valve controlled by the second solenoid valve, and a third solenoid valve and a valve controlled by the third solenoid valve are set in sequence from the top of the monitoring space to the pipeline to divide the monitoring space into a monitoring upper chamber and a monitoring lower chamber, a hydrogen sensor and a methane sensor are set on the inner wall of the monitoring upper chamber, and a pressure sensor is set on the pipeline.

[0014] Optionally, the acquiring the first concentration data of methane in the pipeline, the first concentration data of hydrogen, and the pressure data in the pipeline output by the pipeline gas monitoring unit includes:

[0015] In the non-monitoring state, the first solenoid valve is controlled to open the valve controlled by the first solenoid valve, the third solenoid valve is controlled to open the valve controlled by the third solenoid valve, the upper chamber is monitored to be connected with the air, the upper chamber is monitored to be filled with air, the lower chamber is monitored to be connected with the gas pipeline, and the lower chamber is monitored to be filled with gas;

[0016] In the monitoring state, monitoring is performed according to a preset cycle. At the beginning of monitoring, the first solenoid valve is controlled to close the valve controlled by the first solenoid valve, and the third solenoid valve is controlled to close the valve controlled by the third solenoid valve. After stabilization, the second solenoid valve is controlled to open the valve controlled by the second solenoid valve. The air in the upper monitoring chamber and the gas in the lower monitoring chamber are mixed with each other. After the mixing is uniform, the readings of the methane sensor and the hydrogen sensor installed on the inner wall of the upper monitoring chamber are read to obtain the first concentration data of methane and the first concentration data of hydrogen in the pipeline, and the reading of the pressure sensor set on the pipeline is read to obtain the pressure data in the pipeline.

[0017] Optionally, the gas concentration monitoring unit at the pipeline interface / valve is set in a preset manner, including:

[0018] The gas concentration monitoring unit at the pipeline interface / valve is configured as follows: a methane sensor is set at a distance d2 from the pipeline interface / valve, and a hydrogen sensor is set at a distance d1 from the pipeline interface / valve, wherein:

[0019] Optionally, the second preset condition includes:

[0020] The monitoring results of concentrations lower than the warning value are accumulated, and when the accumulated concentration exceeds the warning value, the second preset condition is met.

[0021] Optionally, the step of setting up an indoor online gas leakage monitoring unit in a preset manner includes:

[0022] The indoor online monitoring unit for gas leakage is configured as follows: a hydrogen sensor and a methane sensor are arranged in a room with a converging roof.

[0023] Optionally, calculating the leakage location according to the diffusion rate of hydrogen in air and the diffusion rate of methane in air includes:

[0024] Calculate the diffusion rate of hydrogen in air and the diffusion rate of methane in air:

[0025]

[0026] Where D is the diffusion coefficient of binary gas A and B, P is the total pressure of the gas, T is the temperature of the gas, M A 、M B is the molar mass of components A and B, ∑v A ,∑v B is the diffusion volume of components A and B molecules; the diffusion coefficient D H2 =0.634cm 2 / s;D CH4 =0.196cm 2 / s;

[0027] Calculate the distance d4 between the leak location and the hydrogen sensor and the methane sensor:

[0028]

[0029] According to the distance d3 between the hydrogen sensor and the methane sensor and the pipeline, the distance d5 between the leakage position and the projections of the hydrogen sensor and the methane sensor to the pipeline is calculated.

[0030] Optionally, establishing a hydrogen-methane dynamic explosion limit calculation model includes:

[0031] Establish a mapping relationship between hydrogen mixture volume ratio and lower explosion limit:

[0032]

[0033] Where: φ is the hydrogen mixing volume ratio, LEL CH4 =5% is the lower explosion limit of methane under standard working conditions, LEL H2 =4% is the lower explosion limit of hydrogen under standard working conditions, K env is the environmental compensation factor, RH is relative humidity, K leak is the leakage dynamic factor, Q is the volume leakage, v is the leakage flow rate, A vent is the equivalent area of ​​the pressure relief port.

[0034] A second aspect of the present invention provides a multi-scenario leakage monitoring and early warning system for natural gas hydrogen blending, comprising:

[0035] Pipeline gas monitoring units, pipeline interface / valve gas concentration monitoring units, and indoor online gas leakage monitoring units set up in a preset manner; and

[0036] a backend data processing unit configured to configure a pipeline gas monitoring unit, a pipeline interface / valve gas concentration monitoring unit, and a gas leakage indoor online monitoring unit in a preset manner; obtain first methane concentration data, first hydrogen concentration data, and pipeline pressure data output by the pipeline gas monitoring unit; calculate a pipeline hydrogen volume ratio based on the first methane concentration data and the first hydrogen concentration data; and compare the calculated volume ratio with a first methane concentration warning value, a first hydrogen concentration warning value, a first pressure warning value, and a hydrogen volume ratio warning value, respectively; and generate a first alarm message if a first preset condition is met; The second concentration data of methane and the second concentration data of hydrogen at the pipeline interface / valve output by the gas concentration monitoring unit at the pipeline interface / valve are obtained, and compared with the second methane concentration warning value and the second hydrogen concentration warning value. If the second preset condition is met, a second alarm message is generated; the methane concentration data and the hydrogen concentration data output by the indoor online monitoring unit for gas leakage are obtained, and the leakage location is calculated according to the diffusion rate of hydrogen in the air and the diffusion rate of methane in the air; a hydrogen-methane dynamic explosion limit calculation model is established; and different levels of warning signals are triggered according to the leakage situation and the diffusion situation.

[0037] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned multi-scenario leakage monitoring and early warning method for natural gas hydrogen blending.

[0038] It can be seen that the multi-scenario leakage monitoring and early warning method, system and computer-readable storage medium for hydrogen-blended natural gas provided by the present invention can realize accurate identification and high-precision monitoring of leakage signals through sensor fusion technology and self-learning mechanism, which can significantly improve monitoring accuracy; the application of deep learning early warning models and multi-level early warning strategies improves the accuracy and timeliness of early warnings, wins valuable time for emergency response, enhances the intelligence of early warnings, solves the key problems of insufficient accuracy of hydrogen-blended natural gas leakage monitoring and low level of early warning intelligence in the existing technology, and improves the safety of hydrogen-blended natural gas transportation. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0040] Figure 1 A flowchart of a multi-scenario leakage monitoring and early warning method for natural gas hydrogen-blended gas provided by an embodiment of the present invention;

[0041] Figure 2 A schematic diagram of the structure of a multi-scenario leakage monitoring and early warning system for natural gas hydrogen blending provided by an embodiment of the present invention;

[0042] Figure 3 A schematic structural diagram of a pipeline gas monitoring unit of a multi-scenario leakage monitoring and early warning system for natural gas hydrogen blending provided by an embodiment of the present invention;

[0043] Figure 4 A schematic structural diagram of a gas concentration monitoring unit at a pipeline interface / valve of a multi-scenario leakage monitoring and early warning system for natural gas hydrogen blending provided by an embodiment of the present invention;

[0044] Figure 5 A schematic structural diagram of a gas leakage indoor online monitoring unit of a natural gas hydrogen-blended multi-scenario leakage monitoring and early warning system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0045] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0046] Figure 1A flow chart of the natural gas hydrogen blending multi-scene leakage monitoring and early warning method provided by the embodiment of the present application is shown, see Figure 1 The natural gas hydrogen blending multi-scene leakage monitoring and early warning method provided by the embodiment of the present application comprises:

[0047] S1, setting a pipeline gas monitoring unit, a pipeline interface / valve gas concentration monitoring unit and an indoor gas leakage online monitoring unit according to a preset mode.

[0048] Specifically, see Figure 2 The natural gas hydrogen blending multi-scene leakage monitoring and early warning system provided by the embodiment of the present application comprises: a unit for pipeline natural gas concentration monitoring, a unit for gas concentration monitoring at interfaces and valves in a pipeline system, and a unit for indoor gas leakage concentration monitoring and tracing. Each unit comprises monitoring, early warning and alarm functions. Each unit can be connected with a background data processing unit, so as to intelligently analyze and process data collected by each sensor.

[0049] As an optional implementation of the embodiment of the present application, the pipeline gas monitoring unit set according to the preset mode comprises:

[0050] The pipeline gas monitoring unit is configured to: open a monitoring hole on the pipeline, set a monitoring space at the monitoring hole, sequentially set a first electromagnetic valve and a valve controlled by the first electromagnetic valve, a second electromagnetic valve and a valve controlled by the second electromagnetic valve, and a third electromagnetic valve and a valve controlled by the third electromagnetic valve on the pipeline from the monitoring space to the pipeline direction, divide the monitoring space into a monitoring upper cavity and a monitoring lower cavity, set a hydrogen sensor and a methane sensor on the inner wall of the monitoring upper cavity, and set a pressure sensor on the pipeline.

[0051] Specifically, see Figure 3 The pipeline gas monitoring unit provided by the embodiment of the present application comprises: a gas delivery pipeline 1; a monitoring hole 2 opened on the pipeline; first, second and third explosion-proof electromagnetic valves 3, 4 and 5; a hydrogen sensor 6; a methane sensor 7; valves 8, 9 and 10 controlled by the first, second and third electromagnetic valves; a monitoring upper cavity 11; a monitoring lower cavity 12; and a pressure sensor 13.

[0052] As an optional implementation of the embodiment of the present application, the pipeline interface / valve gas concentration monitoring unit set according to the preset mode comprises:

[0053] The pipeline interface / valve gas concentration monitoring unit is configured to: set a methane sensor at a distance d2 from the pipeline interface / valve, and set a hydrogen sensor at a distance d1 from the pipeline interface / valve, wherein:

[0054] Specifically, see Figure 4The gas concentration monitoring unit at the pipeline interface / valve includes: hydrogen sensor 6; methane sensor 7; pipeline interface, valve, etc. 14. The installation height is based on the principle of hydrogen sensor on top and methane sensor on the bottom, leaving space for operation. The specific installation heights d1 and d2 are designed according to site conditions.

[0055] As an optional implementation of the embodiment of the present invention, the setting of the indoor online gas leakage monitoring unit in a preset manner includes:

[0056] The indoor online monitoring unit for gas leakage is configured as follows: a hydrogen sensor and a methane sensor are arranged in a room with a converging roof.

[0057] Specifically, see Figure 5 , a hydrogen sensor and a methane sensor are set in a room with a converging top.

[0058] S2, obtaining first methane concentration data, first hydrogen concentration data, and pipeline pressure data output by the pipeline gas monitoring unit, calculating the volume ratio of pipeline hydrogen based on the first methane concentration data and the first hydrogen concentration data, and comparing them with the first methane concentration warning value, the first hydrogen concentration warning value, the first pressure warning value, and the hydrogen volume ratio warning value, respectively. If a first preset condition is met, generating a first alarm message.

[0059] As an optional implementation of the embodiment of the present invention, obtaining the first concentration data of methane in the pipeline, the first concentration data of hydrogen, and the pressure data in the pipeline output by the pipeline gas monitoring unit includes:

[0060] In the non-monitoring state, the first solenoid valve is controlled to open the valve controlled by the first solenoid valve, the third solenoid valve is controlled to open the valve controlled by the third solenoid valve, the upper chamber is monitored to be connected with the air, the upper chamber is monitored to be filled with air, the lower chamber is monitored to be connected with the gas pipeline, and the lower chamber is monitored to be filled with gas;

[0061] In the monitoring state, monitoring is performed according to a preset cycle. At the beginning of monitoring, the first solenoid valve is controlled to close the valve controlled by the first solenoid valve, and the third solenoid valve is controlled to close the valve controlled by the third solenoid valve. After stabilization, the second solenoid valve is controlled to open the valve controlled by the second solenoid valve. The air in the upper monitoring chamber and the gas in the lower monitoring chamber are mixed with each other. After the mixing is uniform, the readings of the methane sensor and the hydrogen sensor installed on the inner wall of the upper monitoring chamber are read to obtain the first concentration data of methane and the first concentration data of hydrogen in the pipeline, and the reading of the pressure sensor set on the pipeline is read to obtain the pressure data in the pipeline.

[0062] For specific implementation, see Figure 3During the working process, when the monitoring state is not in progress, the solenoid valve 3 is controlled to open the valve 8, which is in the open state. The solenoid valve 5 is controlled to open the valve 10. At this time, the upper chamber 11 is monitored to be connected to the air, and the upper chamber is filled with air. The lower chamber 12 is connected to the gas pipeline, and the lower chamber is filled with gas. Set up the program and perform monitoring at regular intervals. For example, set a monitoring cycle every 2 hours (or longer). At the beginning of the monitoring, the solenoid valve 3 is controlled to close the valve 8, and the solenoid valve 5 is controlled to close the valve 10. After stabilization, the solenoid valve 4 is controlled to open the valve 9. This is because the air in the upper chamber 11 and the gas in the lower chamber 12 are mixed with each other. After the mixture is evenly mixed, the readings of the methane sensor 7 and the hydrogen sensor 6 installed on the inner wall of the upper chamber are read to monitor the concentrations of methane and hydrogen in the pipeline, and to determine whether the gas transported in the pipeline meets the user's needs. At the same time, the reading of the pipeline pressure sensor 13 is combined to determine whether the pipeline pressure is normal.

[0063] At the same time, the concentrations of methane and hydrogen in the pipeline, as well as the pipeline pressure data, are transmitted and stored to the backend data processing unit. This data is analyzed and processed to determine the volume ratio of hydrogen in the pipeline. Furthermore, based on pre-set warning values ​​for methane and hydrogen concentrations, pipeline pressure, and hydrogen volume ratio, the system can intervene and issue an alarm if the concentrations fall below the warning values.

[0064] The device can regularly monitor the concentrations of methane and hydrogen in the pipeline to avoid poor ignition caused by an excessively high volume ratio of hydrogen in the fuel gas; it can also monitor the pressure in the pipeline to avoid danger caused by insufficient fuel gas pressure; it provides air in the test environment to avoid inaccurate measurements of methane and hydrogen sensors in the absence of oxygen, and avoids the influence of pipeline pressure when testing directly in the pipeline.

[0065] S3, obtaining the second concentration data of methane and the second concentration data of hydrogen at the pipeline interface / valve output by the gas concentration monitoring unit at the pipeline interface / valve, and comparing them with the second methane concentration warning value and the second hydrogen concentration warning value. If the second preset condition is met, a second alarm message is generated.

[0066] During specific implementation, the present invention sets the secondary alarm limit of the methane sensor and sets the corresponding primary alarm limit of the hydrogen sensor according to the hydrogen blending ratio. When the methane sensor reaches the secondary alarm limit and the hydrogen sensor reaches the primary alarm limit at the same time, timely measures need to be taken to find the leakage point and deal with it.

[0067] The monitored methane and hydrogen concentrations are transmitted and stored to the backend data processing unit for analysis and processing. Based on the system-set methane and hydrogen concentration warning values, an alarm is issued if the concentration falls below the warning value.

[0068] As an optional implementation of the embodiment of the present invention, the second preset condition includes: accumulating monitoring results with concentrations lower than the warning value, and when the accumulated concentration exceeds the warning value, the second preset condition is met.

[0069] Specifically, gas concentration monitoring at pipeline interfaces and valves uses real-time monitoring and cumulative summation methods. When hydrogen and methane concentrations above the pipeline, near valves, and around interfaces exceed a certain concentration, an early warning is issued. Monitoring results with concentrations below the warning value are accumulated, and when the accumulated concentration reaches a certain level (the specific concentration is related to the hydrogen blending ratio and pipeline pressure), an early warning is issued. When the accumulated hydrogen or methane concentration reaches the warning value, the pressure in the pipeline and the accumulated hydrogen concentration in the room need to be paid attention to. At the same time, methane and hydrogen concentrations are monitored near interfaces and valves, and the installation height of hydrogen is higher than that of methane. The height ratio is set according to the molecular weight diffusion rate, and the response ratio corresponds to the ratio of hydrogen added to the gas to avoid natural gas leakage caused by poor sealing.

[0070] The various warning values ​​in the present invention can be set according to actual needs and can be set to multi-level warning thresholds.

[0071] S4, obtaining the methane concentration data and the hydrogen concentration data output by the online monitoring unit in the gas leakage room, and calculating the leakage position according to the diffusion rate of hydrogen in the air and the diffusion rate of methane in the air.

[0072] As an optional implementation manner of the embodiment of the present invention, the calculating the leakage location according to the diffusion rate of hydrogen in air and the diffusion rate of methane in air includes:

[0073] Calculate the diffusion rate of hydrogen in air and the diffusion rate of methane in air:

[0074]

[0075] Where, is the diffusion coefficient of binary gas A and B, P is the total pressure of the gas, T is the temperature of the gas, M A 、M B is the molar mass of components A and B, ∑v A ,∑v B is the diffusion volume of components A and B molecules; the diffusion coefficient D H2 =0.634cm 2 / s;D CH4 =0.196cm 2 / s;

[0076] Calculate the distance d4 between the leak location and the hydrogen sensor and the methane sensor:

[0077]

[0078] According to the distance d3 between the hydrogen sensor and the methane sensor and the pipeline, the distance d5 between the leakage position and the projections of the hydrogen sensor and the methane sensor to the pipeline is calculated.

[0079] For specific implementation, see Figure 5 The figure shows a room with a converging roof. If a gas leak occurs in the indoor gas pipeline, hydrogen and methane components will move upward. At the converging point at the top of the room, hydrogen and methane sensors located there will detect the leaking gas. Based on the time difference between the hydrogen sensor's warning value alarm and the methane sensor's first-level alarm, the diffusion rates of hydrogen and methane in air can be calculated using Fick's diffusion law and Fuller's formula. The time difference can be used to calculate the length d4, and from the known d3, the length d5 ​​can be calculated, providing evidence for leak detection.

[0080]

[0081] Where D is the diffusion coefficient of binary gases A and B, m 2 / s; P - total pressure of gas, Pa; T - temperature of gas, K; MA, MB - molar mass of components A, B, kg / kmol; ∑vA, ∑vB - molecular diffusion volume of components A, B, cm 3 / mol

[0082]

[0083] D H2 =0.634cm 2 / s;D CH4 =0.196cm 2 / s;

[0084] The background data processing unit records and stores the alarm time of the hydrogen and methane monitors, automatically calculates the location of the leak based on theoretical calculations, and provides direction and data support for subsequent repairs and disposal.

[0085] S5, establish a calculation model for the dynamic explosion limit of hydrogen-methane;

[0086] S6, set multi-level warning thresholds to trigger different levels of warning signals according to the severity and spread speed of the leak.

[0087] As an optional implementation of the embodiment of the present invention, the hydrogen-methane dynamic explosion limit calculation model includes:

[0088] Establishing the mapping relationship between hydrogen mixture volume ratio and lower explosion limit includes:

[0089]

[0090] in: is the hydrogen mixing volume ratio, LEL CH4 =5% is the lower explosion limit of methane under standard working conditions, LEL H2 =4% is the lower explosion limit of hydrogen under standard working conditions, K env is the environmental compensation factor, RH is relative humidity, K leak is the leakage dynamic factor, Q is the volume leakage, v is the leakage flow rate, A vent is the equivalent area of ​​the pressure relief port.

[0091] In practice, the present invention features intelligent data processing capabilities, integrating advanced signal processing algorithms and machine learning models to filter environmental noise. It performs real-time and fused analysis of data transmitted by multiple sensors. Using historical data to train models, it automatically identifies and learns leak patterns, improving monitoring accuracy and leak signal recognition precision. Furthermore, by establishing a pipeline operating status model and comparing normal operating parameters with actual monitoring and fused analysis data in real time, it can quickly determine the presence, location, and extent of leaks when abnormal data fluctuations occur.

[0092] Among them, when the present invention realizes the early warning function: the background data processing unit is connected to the leakage monitoring unit, receives and processes the sensor data, and establishes a hydrogen-methane dynamic explosion limit calculation model early warning based on big data analysis technology. It comprehensively considers factors such as hydrogen blending ratio, hydrogen lower explosion limit, methane lower explosion limit, volume leakage, leakage rate, environmental conditions, etc., sets multi-level early warning thresholds, and automatically triggers different levels of early warning signals according to the severity and diffusion rate of the leak, including minor leak warning, moderate leak alarm and serious leak emergency alarm, to ensure that corresponding measures are taken in time. The early warning information is not only conveyed to relevant personnel through sound and light alarms, information notifications, etc., but also pushed instantly through mobile APPs, smart wearable devices, etc., to ensure the timeliness and accuracy of information transmission. Using machine learning algorithms, based on historical early warning data and actual response situations, the early warning model is continuously optimized to improve the accuracy and timeliness of the early warning.

[0093] The calculation model of hydrogen-methane dynamic explosion limit is as follows:

[0094] Establish the mapping relationship between hydrogen mixing volume ratio φ and lower explosion limit:

[0095]

[0096] Where:

[0097] LEL CH4 =5%,LEL H2=4% (lower explosion limit under standard working conditions)

[0098] K env : Environmental compensation factor

[0099]

[0100] RH: relative humidity%

[0101] K leak :Leakage dynamic factor

[0102]

[0103] Q: Volume leakage m 3 / s

[0104] v: Leakage flow rate m / s

[0105] A vent : Equivalent area of ​​pressure relief port m 2

[0106] The present invention implements a leak monitoring function by employing a multi-sensor fusion approach, deploying high-precision hydrogen monitoring equipment, methane monitoring equipment, pressure monitoring equipment, temperature monitoring equipment, and leakage flow rate and leakage volume monitoring equipment at key pipeline nodes and leak-prone areas, such as valves, joints, and welds. The hydrogen sensor utilizes the hydrogen-sensitive properties of a highly sensitive and long-lived palladium alloy thin film. When exposed to hydrogen, the film's resistance changes, thereby detecting hydrogen concentration. The methane sensor uses infrared principles to detect natural gas concentration. The pressure sensor and temperature sensor monitor environmental pressure and temperature changes in real time. Through sensor fusion technology, comprehensive multi-dimensional and multi-parameter monitoring is achieved, forming a complementary monitoring network. Combined with intelligent sensor networks and big data analysis technologies, the recognition accuracy and anti-interference capabilities of leak signals are improved, enabling precise positioning and assessment of leak locations and volumes.

[0107] It can be seen that the multi-scenario leakage monitoring and early warning method for natural gas hydrogen blending provided by the embodiment of the present invention adopts multi-sensor fusion monitoring, and adopts a composite sensor network composed of a hydrogen sensor with hydrogen-sensitive characteristics of a palladium alloy thin film, a methane sensor based on the infrared absorption principle, and high-precision pressure and temperature sensors. The advantages of each sensor complement each other and can accurately detect changes in hydrogen and methane concentrations as well as parameters such as pressure and temperature, greatly improving the monitoring accuracy and comprehensiveness; at the same time, intelligent data analysis and early warning can be performed, and big data analysis technology is used to deeply fuse and analyze multi-source sensor data to establish a dynamic operation model; the present invention can more accurately judge the leakage status by comparing normal and abnormal data in real time, and can also achieve multi-level early warnings, such as on-site sound and light, text messages, and remote monitoring center push, to ensure timely notification of relevant personnel.

[0108] In summary, the present application realizes accurate identification and high-precision monitoring of leakage signals through sensor fusion technology and self-learning mechanism, can significantly improve the monitoring accuracy, and improves the accuracy and timeliness of early warning through the application of a deep learning early warning model and a multi-level early warning strategy, thereby winning valuable time for emergency response and enhancing the intelligentization of early warning.

[0109] Figure 2 The structure of the natural gas hydrogen blending multi-scene leakage monitoring and early warning system provided by the embodiment of the present application is shown, which applies the above method, and only the structure of the natural gas hydrogen blending multi-scene leakage monitoring and early warning system is briefly described below. For other details, please refer to the related description in the natural gas hydrogen blending multi-scene leakage monitoring and early warning method above, see Figure 2 The natural gas hydrogen blending multi-scene leakage monitoring and early warning system provided by the embodiment of the present application comprises:

[0110] The pipeline gas monitoring unit, the pipeline interface / valve gas concentration monitoring unit and the gas leakage indoor online monitoring unit are set in a preset manner; and

[0111] The background data processing unit is configured to set the pipeline gas monitoring unit, the pipeline interface / valve gas concentration monitoring unit and the gas leakage indoor online monitoring unit in a preset manner, acquire the first concentration data of methane and the first concentration data of hydrogen in the pipeline output by the pipeline gas monitoring unit, calculate the volume ratio of hydrogen in the pipeline according to the first concentration data of methane and the first concentration data of hydrogen, and compare the volume ratio of hydrogen with the first methane concentration early warning value, the first hydrogen concentration early warning value, the first pressure early warning value and the hydrogen volume ratio early warning value respectively, and if the first preset condition is met, generate the first alarm information; acquire the second concentration data of methane and the second concentration data of hydrogen at the pipeline interface / valve output by the pipeline interface / valve gas concentration monitoring unit, and compare the second concentration data of methane and the second concentration data of hydrogen with the second methane concentration early warning value and the second hydrogen concentration early warning value respectively, and if the second preset condition is met, generate the second alarm information; acquire the concentration data of methane and the concentration data of hydrogen output by the gas leakage indoor online monitoring unit, calculate the leakage position according to the diffusion rate of hydrogen in air and the diffusion rate of methane in air, establish a hydrogen-methane dynamic explosion limit calculation model, and trigger different levels of early warning signals according to the leakage situation and the diffusion situation.

[0112] As an optional implementation manner of the embodiment of the present application, the pipeline gas monitoring unit is set in the following manner:

[0113] The pipeline gas monitoring unit is configured as follows: a monitoring hole is opened on the pipeline, a monitoring space is set at the monitoring hole, a first solenoid valve and a valve controlled by the first solenoid valve, a second solenoid valve and a valve controlled by the second solenoid valve, and a third solenoid valve and a valve controlled by the third solenoid valve are set in sequence from the top of the monitoring space to the pipeline to divide the monitoring space into a monitoring upper chamber and a monitoring lower chamber, a hydrogen sensor and a methane sensor are set on the inner wall of the monitoring upper chamber, and a pressure sensor is set on the pipeline.

[0114] As an optional implementation of the embodiment of the present invention, the background data processing unit obtains the first methane concentration data, the first hydrogen concentration data, and the pipeline pressure data output by the pipeline gas monitoring unit in the following manner:

[0115] In the non-monitoring state, the first solenoid valve is controlled to open the valve controlled by the first solenoid valve, the third solenoid valve is controlled to open the valve controlled by the third solenoid valve, the upper chamber is monitored to be connected with the air, the upper chamber is monitored to be filled with air, the lower chamber is monitored to be connected with the gas pipeline, and the lower chamber is monitored to be filled with gas;

[0116] In the monitoring state, monitoring is performed according to a preset cycle. At the beginning of monitoring, the first solenoid valve is controlled to close the valve controlled by the first solenoid valve, and the third solenoid valve is controlled to close the valve controlled by the third solenoid valve. After stabilization, the second solenoid valve is controlled to open the valve controlled by the second solenoid valve. The air in the upper monitoring chamber and the gas in the lower monitoring chamber are mixed with each other. After the mixing is uniform, the readings of the methane sensor and the hydrogen sensor installed on the inner wall of the upper monitoring chamber are read to obtain the first concentration data of methane and the first concentration data of hydrogen in the pipeline, and the reading of the pressure sensor set on the pipeline is read to obtain the pressure data in the pipeline.

[0117] As an optional implementation of the embodiment of the present invention, the gas concentration monitoring unit at the pipeline interface / valve is set in the following manner:

[0118] The gas concentration monitoring unit at the pipeline interface / valve is configured as follows: a methane sensor is set at a distance d2 from the pipeline interface / valve, and a hydrogen sensor is set at a distance d1 from the pipeline interface / valve, wherein:

[0119] As an optional implementation manner of the embodiment of the present invention, the second preset condition includes:

[0120] The monitoring results of concentrations lower than the warning value are accumulated, and when the accumulated concentration exceeds the warning value, the second preset condition is met.

[0121] As an optional implementation of the embodiment of the present invention, the indoor online monitoring unit for gas leakage is configured as follows:

[0122] The indoor online monitoring unit for gas leakage is configured as follows: a hydrogen sensor and a methane sensor are arranged in a room with a converging roof.

[0123] As an optional implementation of the embodiment of the present invention, the background data processing unit calculates the leakage location according to the diffusion rate of hydrogen in the air and the diffusion rate of methane in the air in the following manner:

[0124] Calculate the diffusion rate of hydrogen in air and the diffusion rate of methane in air:

[0125]

[0126] Where D is the diffusion coefficient of binary gas A and B, P is the total pressure of the gas, T is the temperature of the gas, M A 、M B is the molar mass of components A and B, ∑v A ,∑v B is the diffusion volume of components A and B molecules; the diffusion coefficient D H2 =0.634cm 2 / s;D CH4 =0.196cm 2 / s;

[0127] Calculate the distance d4 between the leak location and the hydrogen sensor and the methane sensor:

[0128]

[0129] According to the distance d3 between the hydrogen sensor and the methane sensor and the pipeline, the distance d5 between the leakage position and the projections of the hydrogen sensor and the methane sensor to the pipeline is calculated.

[0130] As an optional implementation of the embodiment of the present invention, the background data processing unit establishes a hydrogen-methane dynamic explosion limit calculation model in the following manner:

[0131] Establish a mapping relationship between hydrogen mixture volume ratio and lower explosion limit:

[0132]

[0133] in: is the hydrogen mixing volume ratio, LEL CH4 =5% is the lower explosion limit of methane under standard working conditions, LEL H2 =4% is the lower explosion limit of hydrogen under standard working conditions, K env is the environmental compensation factor, RH is relative humidity, K leak is the leakage dynamic factor, Q is the volume leakage, v is the leakage flow rate, A vent is the equivalent area of ​​the pressure relief port.

[0134] It can be seen that the natural gas hydrogen-blended multi-scenario leakage monitoring and early warning system provided by the embodiment of the present invention can achieve accurate identification and high-precision monitoring of leakage signals through sensor fusion technology and self-learning mechanism, which can significantly improve monitoring accuracy; the application of deep learning early warning models and multi-level early warning strategies improves the accuracy and timeliness of early warnings, wins valuable time for emergency response, and enhances the intelligence of early warnings.

[0135] On the other hand, the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned multi-scenario leakage monitoring and early warning method for natural gas hydrogen blending.

[0136] It can be seen that the computer-readable storage medium provided by the embodiment of the present invention can realize accurate identification and high-precision monitoring of leakage signals through sensor fusion technology and self-learning mechanism, which can significantly improve the monitoring accuracy; the application of deep learning early warning models and multi-level early warning strategies can improve the accuracy and timeliness of early warnings, win valuable time for emergency response, and enhance the intelligence of early warnings.

[0137] The above are merely embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A multi-scenario leakage monitoring and early warning method for natural gas hydrogen blending, characterized in that: include: Set up pipeline gas monitoring units, pipeline interface / valve gas concentration monitoring units, and indoor online gas leakage monitoring units according to the preset method; obtaining first methane concentration data, first hydrogen concentration data, and pipeline pressure data output by the pipeline gas monitoring unit, calculating a pipeline hydrogen volume ratio based on the first methane concentration data and the first hydrogen concentration data, and comparing the calculated values ​​with a first methane concentration warning value, a first hydrogen concentration warning value, a first pressure warning value, and a hydrogen volume ratio warning value, respectively; and generating a first alarm message if a first preset condition is met; obtaining second methane concentration data and second hydrogen concentration data at the pipeline interface / valve output by the pipeline interface / valve gas concentration monitoring unit, and comparing them with the second methane concentration warning value and the second hydrogen concentration warning value, and generating a second alarm message if a second preset condition is met; Acquire methane concentration data and hydrogen concentration data output by the online monitoring unit in the gas leakage room, and calculate the leakage location based on the diffusion rate of hydrogen in the air and the diffusion rate of methane in the air; Establish a calculation model for the dynamic explosion limit of hydrogen-methane; Different levels of early warning signals are triggered according to the leakage and spread conditions.

2. The method according to claim 1, characterized in that The pipeline gas monitoring unit is set in a preset manner, including: The pipeline gas monitoring unit is configured as follows: a monitoring hole is opened on the pipeline, a monitoring space is set at the monitoring hole, a first solenoid valve and a valve controlled by the first solenoid valve, a second solenoid valve and a valve controlled by the second solenoid valve, and a third solenoid valve and a valve controlled by the third solenoid valve are set in sequence from the top of the monitoring space to the pipeline to divide the monitoring space into a monitoring upper chamber and a monitoring lower chamber, a hydrogen sensor and a methane sensor are set on the inner wall of the monitoring upper chamber, and a pressure sensor is set on the pipeline.

3. The method according to claim 2, characterized in that The obtaining of first methane concentration data, first hydrogen concentration data, and pipeline pressure data output by the pipeline gas monitoring unit includes: In the non-monitoring state, the first solenoid valve is controlled to open the valve controlled by the first solenoid valve, the third solenoid valve is controlled to open the valve controlled by the third solenoid valve, the upper chamber is monitored to be connected with the air, the upper chamber is monitored to be filled with air, the lower chamber is monitored to be connected with the gas pipeline, and the lower chamber is monitored to be filled with gas; In the monitoring state, monitoring is performed according to a preset cycle. At the beginning of monitoring, the first solenoid valve is controlled to close the valve controlled by the first solenoid valve, and the third solenoid valve is controlled to close the valve controlled by the third solenoid valve. After stabilization, the second solenoid valve is controlled to open the valve controlled by the second solenoid valve. The air in the upper monitoring chamber and the gas in the lower monitoring chamber are mixed with each other. After the mixing is uniform, the readings of the methane sensor and the hydrogen sensor installed on the inner wall of the upper monitoring chamber are read to obtain the first concentration data of methane and the first concentration data of hydrogen in the pipeline, and the reading of the pressure sensor set on the pipeline is read to obtain the pressure data in the pipeline.

4. The method according to claim 3, characterized in that The gas concentration monitoring unit at the pipeline interface / valve is set in a preset manner, including: The gas concentration monitoring unit at the pipeline interface / valve is configured as follows: a methane sensor is set at a distance d2 from the pipeline interface / valve, and a hydrogen sensor is set at a distance d1 from the pipeline interface / valve, wherein:

5. The method according to claim 4, characterized in that The second preset condition includes: The monitoring results of concentrations lower than the warning value are accumulated, and when the accumulated concentration exceeds the warning value, the second preset condition is met.

6. The method according to claim 5, characterized in that The method of setting up the indoor online gas leakage monitoring unit in a preset manner includes: The indoor online monitoring unit for gas leakage is configured as follows: a hydrogen sensor and a methane sensor are arranged in a room with a converging roof.

7. The method according to claim 6, characterized in that Calculating the leakage location according to the diffusion rate of hydrogen in air and the diffusion rate of methane in air includes: Calculate the diffusion rate of hydrogen in air and the diffusion rate of methane in air: Where D is the diffusion coefficient of binary gas A and B, P is the total pressure of the gas, T is the temperature of the gas, M A 、M B is the molar mass of components A and B, ∑v A ,∑v B is the diffusion volume of components A and B molecules; the diffusion coefficient D H2 =0.634cm 2 / s;D CH4 =0.196cm 2 / s; Calculate the distance d4 between the leak location and the hydrogen sensor and the methane sensor: According to the distance d3 between the hydrogen sensor and the methane sensor and the pipeline, the distance d5 between the leakage position and the projections of the hydrogen sensor and the methane sensor to the pipeline is calculated.

8. The method according to claim 1, characterized in that The establishment of the hydrogen-methane dynamic explosion limit calculation model comprises: Establish a mapping relationship between hydrogen mixture volume ratio and lower explosion limit: in: is the hydrogen mixing volume ratio, LEL CH4 =5% is the lower explosion limit of methane under standard working conditions, LEL H2 =4% is the lower explosion limit of hydrogen under standard working conditions, K env is the environmental compensation factor, RH is relative humidity, K leak is the leakage dynamic factor, Q is the volume leakage, v is the leakage flow rate, A vent is the equivalent area of ​​the pressure relief port.

9. A natural gas hydrogen-blended multi-scenario leakage monitoring and early warning system, characterized in that: include: Pipeline gas monitoring units, pipeline interface / valve gas concentration monitoring units, and indoor online gas leakage monitoring units set up in a preset manner; as well as Backend data processing unit for The pipeline gas monitoring unit, the pipeline interface / valve gas concentration monitoring unit, and the gas leakage indoor online monitoring unit are set in a preset manner; the first methane concentration data, the first hydrogen concentration data, and the pipeline pressure data output by the pipeline gas monitoring unit are obtained, and the volume ratio of the pipeline hydrogen is calculated based on the first methane concentration data and the first hydrogen concentration data, and compared with the first methane concentration warning value, the first hydrogen concentration warning value, the first pressure warning value, and the hydrogen volume ratio warning value, respectively. If the first preset condition is met, a first alarm message is generated; the second methane concentration data and the second hydrogen concentration data at the pipeline interface / valve are obtained from the pipeline interface / valve gas concentration monitoring unit, and compared with the second methane concentration warning value and the second hydrogen concentration warning value. If the second preset condition is met, a second alarm message is generated; The methane concentration data and hydrogen concentration data output by the online monitoring unit in the gas leakage room are obtained, and the leakage location is calculated based on the diffusion rate of hydrogen in the air and the diffusion rate of methane in the air; a hydrogen-methane dynamic explosion limit calculation model is established; and different levels of early warning signals are triggered according to the leakage and diffusion conditions.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the multi-scenario leakage monitoring and early warning method for natural gas mixed with hydrogen as described in any one of claims 1 to 8 is implemented.

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