Hydrogen safety rapid early warning method based on hydrogen micro leakage judgment

Abstract

The invention relates to a hydrogen safety rapid early warning method based on hydrogen micro leakage judgment. The early warning method comprises the following steps: acquiring technological process information of a hydrogen refueling station system, and carrying out hazard source identification to obtain a hazard source identification result; a risk point where hydrogen leakage is likely to happen in the hydrogen refueling station is determined, and a combined criterion of the hydrogen concentration change rate, the hydrogen concentration sudden change value and the hydrogen concentration threshold value is formulated; carrying out a hydrogen leakage test, and determining a parameter threshold value of a hydrogen leakage criterion; and obtaining a fault state operation parameter change rule, and positioning hydrogen leakage so as to realize rapid early warning of hydrogen leakage. Compared with the prior art, the micro leakage test and the fault state operation parameter test are combined, the leakage alarm is realized at the hydrogen micro leakage stage, and the safety of the hydrogen related system can be improved to a great extent. The method is not only suitable for rapid early warning of hydrogen leakage of a hydrogen related system, but also suitable for leakage early warning of other toxic gases or combustible gases, and has wide application scenarios.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen utilization system safety, and in particular to a hydrogen safety rapid early warning method based on hydrogen micro-leakage determination. Background Art

[0002] As a secondary energy with a wide range of sources, hydrogen energy has the advantages of high combustion calorific value, convenient storage and transportation, and zero terminal emissions. It is regarded as one of the most promising clean energy sources in the future and an important way to achieve the "dual carbon" goal. However, due to the characteristics of hydrogen being colorless and odorless, low ignition energy, large diffusion coefficient, and wide combustion range, there are potential leakage and explosion risks in all links of hydrogen energy production and application. The research on hydrogen safety early warning technology is a hot and difficult issue in the field of hydrogen safety.

[0003] Conventional hydrogen safety warning technologies include placing a small number of hydrogen concentration sensors at the air inlets and outlets of buildings and near hydrogen-related equipment, and setting a larger hydrogen concentration alarm value to implement hydrogen leakage alarms. However, due to the delay from hydrogen leakage to diffusion and the long response time of hydrogen concentration sensors, it is difficult to achieve rapid warning of hydrogen leakage, which can easily cause hydrogen to gather into combustible clouds and create the risk of combustion and explosion.

[0004] Therefore, there is an urgent need to study an effective and rapid method for determining hydrogen micro-leakage, which can help to issue a hydrogen leak alarm when hydrogen micro-leakage occurs and prevent the formation of flammable hydrogen clouds. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a hydrogen safety rapid warning method based on hydrogen micro-leakage judgment. By formulating a hydrogen micro-leakage judgment criterion combining the hydrogen concentration change rate, hydrogen concentration mutation and hydrogen concentration threshold, early detection, early prevention and early maintenance can be achieved, thereby greatly improving the operating safety of hydrogen utilization systems such as hydrogen refueling stations and cogeneration systems.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] The present invention provides a hydrogen safety rapid early warning method based on hydrogen micro-leakage judgment, comprising the following steps:

[0008] S1: Obtain the process flow information of the hydrogen refueling station system, identify the hazard sources by using hazard and operability analysis and failure mode and effect analysis, and obtain the hazard source identification results;

[0009] S2: Based on the hazard source identification results obtained in S1, identify the risk points in the hydrogen refueling station that are prone to hydrogen leakage, determine the near-field monitoring layout of the hydrogen concentration sensor, assemble the hydrogen micro-leakage detection device, and formulate the joint judgment criteria for the hydrogen concentration change rate, hydrogen concentration mutation value, and hydrogen concentration threshold;

[0010] S3: Based on the hazard source identification results obtained in S1, and using the hydrogen micro-leakage detection device in S2, a micro-leakage test is carried out to obtain the micro-leakage test results and the leakage evolution law of key leakage points;

[0011] S4: According to the micro-leakage test results in S3, set the simulation conditions, carry out hydrogen micro-leakage fluid dynamics analysis, obtain the hydrogen micro-leakage diffusion law, and determine the parameter threshold of the micro-leakage criterion in S2 in combination with the simulation analysis results;

[0012] S5: Conduct a fault state operating parameter experiment to obtain the law of changes in operating parameters of hydrogen-related equipment under micro-leakage conditions, provide guidance for hydrogen leakage positioning, and use a hydrogen micro-leakage rapid warning device to achieve rapid warning of hydrogen leakage.

[0013] Further, in S2, the hydrogen micro-leakage detection device includes a hydrogen concentration sensor and a sealed cabin, the hydrogen concentration sensor is fixed in the sealed cabin, and an opening is provided at the bottom of the sealed cabin, and the opening is used to collect hydrogen gas that escapes after micro-leakage.

[0014] Furthermore, in S2, when the hydrogen concentration change rate increases, the high-sensitivity hydrogen concentration sensor detects that the hydrogen concentration change rate reaches a preset value and issues a safety warning signal.

[0015] Furthermore, in S2, the hydrogen concentration mutation value is specifically: when the hydrogen concentration sensor detects that the hydrogen concentration changes sharply at a certain moment, it indicates that a fault occurs at the risk point at this moment, and a safety warning signal is issued.

[0016] Furthermore, in S2, the hydrogen concentration threshold is specifically: when a hydrogen-related component leaks continuously and extremely slowly, the hydrogen concentration in the environment increases, and a highly sensitive hydrogen concentration sensor monitors the amount of hydrogen micro-leakage from a dangerous source. When the hydrogen concentration reaches different preset thresholds, the sensor issues a graded warning.

[0017] Furthermore, in S3, the specific process of conducting the hydrogen micro-leakage test is: adjusting the opening of different valves at the hydrogen leakage point to adjust the hydrogen micro-leakage flow rate, and then detecting the hydrogen concentration under different hydrogen micro-leakage flow conditions through a hydrogen concentration sensor to provide a basis for setting the working conditions for simulation analysis.

[0018] Furthermore, in S4, the hydrogen leakage fluid dynamics analysis is specifically carried out as follows: a three-dimensional model of the hydrogen utilization system is established through CATIA modeling software, the model is imported into FLACS-CFD computational fluid dynamics simulation software, and simulation conditions are set according to the hydrogen leakage amount detected in S4, the spatiotemporal evolution law of hydrogen leakage diffusion in space under micro-leakage conditions is studied, the hydrogen concentration near the risk point is obtained, and the parameter threshold of the leakage criterion in S2 is determined.

[0019] Furthermore, in S5, the specific process of conducting the fault state operating parameter experiment is: adjusting the opening of different valves at the hydrogen leakage point to adjust the hydrogen micro-leakage flow rate, and then detecting the change pattern of the temperature and pressure parameters of the compressor inlet and outlet, the hydrogen storage bottle mouth valve, and the hydrogen pipeline points through temperature sensors and pressure sensors to provide guidance for hydrogen leakage locating.

[0020] Furthermore, in S2, the combined criterion of the hydrogen concentration change rate, the hydrogen concentration mutation value, and the hydrogen concentration threshold is formulated according to the hydrogen leakage principle.

[0021] Further, in S6, the hydrogen micro-leakage rapid warning device includes a hydrogen concentration sensor, a station control system and an audible and visual alarm;

[0022] The hydrogen concentration sensor is used to sense hydrogen leakage;

[0023] The station control system is used to calculate the monitoring data change value of the system hydrogen concentration sensor in real time. When the change value or hydrogen leakage reaches the alarm threshold, the station control system sends different sound and light alarm control signals according to the micro-leakage criterion;

[0024] The sound and light alarm is used for hydrogen micro-leakage alarm.

[0025] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0026] 1. The core of the hydrogen safety early warning method of the present invention is to realize safety early warning of hydrogen micro-leakage stage. It innovatively proposes hydrogen micro-leakage judgment criteria combining hydrogen concentration change rate, hydrogen concentration mutation and hydrogen concentration threshold, which can achieve early detection, early prevention and early maintenance, and can greatly improve the operation safety of hydrogen utilization systems, such as hydrogen refueling stations and cogeneration systems.

[0027] 2. The hydrogen safety early warning method of the present invention combines hazard source identification with micro-leakage test, proposes a sensor arrangement scheme based on hazard source identification, can quickly and efficiently monitor the micro-leakage of hydrogen-related equipment, and assembles high-precision hydrogen concentration sensors, control systems, and sound and light alarms into Figure 4 A micro-leakage rapid detection device is shown, and the formulated criterion is used to determine hydrogen micro-leakage, which can realize early warning and system safety protection in the initial stage of hydrogen accidents.

[0028] 3. The early warning method of the present invention is not only applicable to the rapid early warning of hydrogen leakage in hydrogen-related systems, but also applicable to the early warning of leakage of other toxic gases or flammable gases, and has a wide range of application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a flow chart of a hydrogen safety rapid early warning method based on hydrogen micro-leakage judgment;

[0030] Figure 2 This is a schematic diagram of the structure of the hydrogen micro-leakage test device in Example 1;

[0031] Figure 3 Schematic diagram of hydrogen concentration change rate of hydrogen micro-leakage criterion in Example 1;

[0032] Figure 4 Schematic diagram of hydrogen concentration mutation according to the hydrogen micro-leakage criterion in Example 1;

[0033] Figure 5 Schematic diagram of hydrogen concentration threshold value for hydrogen micro-leakage criterion in Example 1;

[0034] Figure 6 This is a schematic diagram of the safety protection device in Example 1;

[0035] Figure 2 Description of the mark in:

[0036] 1- Sealed cabin, 2- Hydrogen concentration sensor. DETAILED DESCRIPTION

[0037] The specific implementation methods of the present invention are described in detail below through examples. These examples are implemented on the premise of the scheme described in the present invention, and provide detailed implementation methods and specific operating processes, but the protection scope of the present invention is not limited to the following examples.

[0038] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments. Any features such as component models, material names, connection structures, preparation methods, materials, structures or composition ratios not clearly described in this technical solution are deemed to be common technical features disclosed in the prior art.

[0039] Example 1

[0040] This embodiment provides a hydrogen safety rapid warning method based on hydrogen micro-leakage judgment, such as Figure 1 As shown, the following steps are included:

[0041] S1: Analyze the process flow information of the hydrogen refueling station system, use hazard and operability analysis, failure mode and effect analysis to identify the hazard sources, and obtain the hazard source identification results.

[0042] Hazard and operability analysis (HAZOP) and failure mode and effects analysis (FMEA) are used to identify the hazards of hydrogen-related equipment. Among them, HAZOP is mainly used to analyze the hazards originating from the internal characteristics of the system, as shown in Table 1, which is an excerpt of the HAZOP analysis results of the hydrogen station compressor. FMEA is mainly used to analyze hazards based on the failure mode of each component of the system, as shown in Table 2, which is an excerpt of the FMEA analysis results of the hydrogen station compressor. Therefore, all system hazards are identified through a combination of HAZOP and FMEA, and then the key hazards and risk points in the system are identified to obtain the hazard identification results.

[0043] Table 1 HAZOP analysis (excerpt)

[0044]

[0045]

[0046] Table 2FMEA analysis (excerpt)

[0047]

[0048] S2: Based on the results of the hazard source identification in S1, determine the risk points where hydrogen leakage accidents are likely to occur, and use this as the basis for the hydrogen concentration sensor layout plan. High-precision hydrogen concentration sensors are arranged near the risk points, and hydrogen micro-leakage detection devices are assembled. Figure 2 As shown, the device includes a hydrogen concentration sensor 2 and a sealed cabin 1. The sealed cabin 1 is hemispherical and has an opening at the bottom. The hydrogen concentration sensor 2 is arranged in the sealed cabin 1 to collect hydrogen gas that escapes upward after a micro-leakage, so as to prepare for the next step of hydrogen leakage detection test.

[0049] In hydrogen safety accidents, the components involved have tiny leaks below the alarm threshold of the hydrogen alarm due to manufacturing defects, fatigue vibration, corrosion and other reasons in the early stage. Such tiny leaks will lead to large hydrogen leaks, causing the hydrogen concentration to exceed the combustion and explosion boundary, resulting in a large hydrogen accident. That is, the large-scale hydrogen leak is gradually developed from the previous tiny leaks.

[0050] The specific contents of the hydrogen micro-leakage judgment criteria are as follows: (1) Hydrogen concentration change rate: Due to the processing technology and design and manufacturing defects of mechanical parts, the pipes and valves of the hydrogen system will have extremely small leaks. However, with the increase of service time and the fatigue problems caused by complex working conditions, the amount of small leaks will gradually increase, which will cause the change rate of hydrogen concentration in the system to increase. When the high-sensitivity hydrogen concentration sensor detects that the hydrogen concentration change rate reaches a certain value, a safety warning will be issued to remind the staff to take certain preventive measures, such as Figure 3As shown in (hydrogen concentration change rate s1 = Δc / Δt); (2) Hydrogen concentration mutation value: Under normal circumstances, the amount of hydrogen leakage increases slowly and regularly with the increase of pipe and valve working time or is within a normal fluctuation range. However, under certain working conditions, when the hydrogen concentration sensor detects that the hydrogen concentration has changed dramatically at a certain moment, it means that there are certain fault problems at the risk point at this moment, such as sudden loosening of the valve or the pipe joint. Therefore, when the hydrogen concentration suddenly changes, a safety warning should be issued and appropriate measures should be taken for protection, such as Figure 4 As shown in (hydrogen concentration mutation value s2 = Δc); (3) Hydrogen concentration threshold: When a hydrogen-related component leaks continuously and very slowly, the hydrogen concentration in the environment increases. A highly sensitive hydrogen concentration sensor is used to monitor the amount of hydrogen leakage from the hazardous source. When the hydrogen concentration reaches above the specified threshold, a graded warning will be issued based on the hydrogen concentration value monitored by the sensor, such as Figure 5 shown.

[0051] S3: Based on the results of hazard source identification in S1, determine the hydrogen leakage risk points and hydrogen concentration sensor layout plan, and carry out hydrogen micro-leakage tests based on the hydrogen micro-leakage detection device designed in S2. The specific process is: adjust the opening of different valves at the hydrogen leakage point to adjust the hydrogen micro-leakage flow rate, and then use the hydrogen concentration sensor to detect the hydrogen concentration under different hydrogen micro-leakage flow conditions, providing a basis for the next step of simulation analysis.

[0052] S4: Conduct hydrogen leakage fluid dynamics analysis. Specifically, establish a three-dimensional model of the hydrogen utilization system through CATIA modeling software, import the model into FLACS-CFD computational fluid dynamics simulation software, set up simulation conditions according to the hydrogen leakage detected in S3, study the spatiotemporal evolution law of hydrogen leakage diffusion in space under micro-leakage conditions, obtain the hydrogen concentration near the risk point, and determine the parameter threshold of the leakage criterion in S2.

[0053] In addition, the boundary value of the hydrogen micro-leakage criterion can be dynamically modified according to the service life of the hydrogen refueling station, the operating conditions of the equipment, and the optimized fluid dynamics simulation analysis.

[0054] S5: The specific process of conducting the fault state operation parameter experiment is: adjust the opening of different valves at the hydrogen leakage point to adjust the hydrogen micro-leakage flow rate, and then use temperature sensors and pressure sensors to detect the change patterns of temperature and pressure parameters at points such as the compressor inlet and outlet, hydrogen storage bottle mouth valve, and hydrogen pipeline to provide guidance for hydrogen leakage positioning.

[0055] The hydrogen concentration sensor in S2 is combined with the station control system and the sound and light alarm to form a rapid warning device for hydrogen micro-leakage, such as Figure 6As shown, the hydrogen concentration sensor senses hydrogen leakage; the station control system collects data and issues alarms, wherein the station control system integrates hydrogen leakage criteria; and the sound and light alarm issues hydrogen micro-leakage alarms.

[0056] This embodiment proposes a hydrogen safety rapid warning method based on hydrogen micro-leakage judgment. Through the hazard source identification method combined with HAZOP / FMEA), a sensor layout plan is proposed; innovative micro-leakage criteria of hydrogen concentration change rate, hydrogen concentration mutation and hydrogen concentration threshold are proposed, and combined with micro-leakage detection tests on key risk points of in-service hydrogen-related equipment, the boundary parameters of micro-leakage criteria are determined to provide a reference for the optimization of security system early warning technology; and a security system with micro-leakage criteria written in is proposed, which can effectively realize the safe and rapid warning of hydrogen accidents caused by failures of hydrogen-related system hazard sources such as hydrogen refueling stations. At the same time, it is widely used in mines, natural gas plants and other places.

[0057] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A hydrogen safety rapid warning method based on hydrogen micro-leakage judgment, characterized in that: The following steps are involved: S1: Obtain the process flow information of the hydrogen refueling station system, identify the hazard sources by using hazard and operability analysis and failure mode and effect analysis, and obtain the hazard source identification results; S2: Based on the hazard source identification results obtained in S1, identify the risk points in the hydrogen refueling station that are prone to hydrogen leakage, determine the near-field monitoring layout of the hydrogen concentration sensor, assemble the hydrogen micro-leakage detection device, and formulate the joint judgment criteria for the hydrogen concentration change rate, hydrogen concentration mutation value, and hydrogen concentration threshold; S3: Based on the hazard source identification results obtained in S1, and using the hydrogen micro-leakage detection device in S2, a micro-leakage test is carried out to obtain the micro-leakage test results and the leakage evolution law of key leakage points; S4: According to the micro-leakage test results in S3, set the simulation conditions, carry out hydrogen micro-leakage fluid dynamics analysis, obtain the hydrogen micro-leakage diffusion law, and determine the parameter threshold of the micro-leakage criterion in S2 in combination with the simulation analysis results; S5: Conduct a fault state operating parameter experiment to obtain the law of changes in operating parameters of hydrogen-related equipment under micro-leakage conditions, provide guidance for hydrogen leakage positioning, and use a hydrogen micro-leakage rapid warning device to achieve rapid warning of hydrogen leakage.

2. A hydrogen safety rapid early warning method based on hydrogen micro-leakage judgment according to claim 1, characterized in that: In S2, the hydrogen micro-leakage detection device includes a hydrogen concentration sensor and a sealed cabin, wherein the hydrogen concentration sensor is fixed in the sealed cabin, and an opening is provided at the bottom of the sealed cabin, wherein the opening is used to collect hydrogen gas that escapes after micro-leakage.

3. A hydrogen safety rapid early warning method based on hydrogen micro-leakage judgment according to claim 1, characterized in that: In S2, when the hydrogen concentration change rate increases, the high-sensitivity hydrogen concentration sensor detects that the hydrogen concentration change rate reaches a preset value and issues a safety warning signal.

4. A hydrogen safety rapid early warning method based on hydrogen micro-leakage judgment according to claim 1, characterized in that: In S2, the hydrogen concentration mutation value is specifically: when the hydrogen concentration sensor detects that the hydrogen concentration changes sharply at a certain moment, it indicates that a fault occurs at the risk point at this moment, and a safety warning signal is issued.

5. A hydrogen safety rapid early warning method based on hydrogen micro-leakage judgment according to claim 1, characterized in that: In S2, the hydrogen concentration threshold is specifically: when a hydrogen-related component leaks continuously and extremely slowly, the hydrogen concentration in the environment increases, and a highly sensitive hydrogen concentration sensor monitors the amount of hydrogen micro-leakage from a hazardous source. When the hydrogen concentration reaches different preset thresholds, the sensor issues a graded warning.

6. A hydrogen safety rapid early warning method based on hydrogen micro-leakage judgment according to claim 1, characterized in that: In S3, the specific process of conducting the hydrogen micro-leakage test is: adjusting the opening of different valves at the hydrogen leakage point to adjust the hydrogen micro-leakage flow rate, and then detecting the hydrogen concentration under different hydrogen micro-leakage flow conditions through a hydrogen concentration sensor to provide a basis for the working condition setting of the simulation analysis.

7. A hydrogen safety rapid early warning method based on hydrogen micro-leakage judgment according to claim 1, characterized in that: In S4, the hydrogen leakage fluid dynamics analysis is specifically carried out as follows: a three-dimensional model of the hydrogen utilization system is established through CATIA modeling software, the model is imported into FLACS-CFD computational fluid dynamics simulation software, and simulation conditions are set according to the hydrogen leakage amount detected in S4, the spatiotemporal evolution law of hydrogen leakage diffusion in space under micro-leakage conditions is studied, the hydrogen concentration near the risk point is obtained, and the parameter threshold of the leakage criterion in S2 is determined.

8. The hydrogen safety rapid early warning method based on hydrogen micro-leakage judgment according to claim 1 is characterized in that: In S5, the specific process of conducting the fault state operating parameter experiment is: adjusting the opening of different valves at the hydrogen leakage point to adjust the hydrogen micro-leakage flow rate, and then using temperature sensors and pressure sensors to detect the change patterns of temperature and pressure parameters at the compressor inlet and outlet, hydrogen storage bottle mouth valve, and hydrogen pipeline points to provide guidance for hydrogen leakage locating.

9. A hydrogen safety rapid early warning method based on hydrogen micro-leakage judgment according to claim 1, characterized in that: In S2, the combined criterion of the hydrogen concentration change rate, hydrogen concentration mutation value, and hydrogen concentration threshold is formulated according to the hydrogen leakage principle.

10. A hydrogen safety rapid early warning method based on hydrogen micro-leakage judgment according to claim 1, characterized in that: In S6, the hydrogen micro-leakage rapid warning device includes a hydrogen concentration sensor, a station control system and an audible and visual alarm; The hydrogen concentration sensor is used to sense hydrogen leakage; The station control system is used to calculate the monitoring data change value of the system hydrogen concentration sensor in real time. When the change value or hydrogen leakage reaches the alarm threshold, the station control system sends different sound and light alarm control signals according to the micro-leakage criterion; The sound and light alarm is used for hydrogen micro-leakage alarm.

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