A hydrogen leakage rapid detection device and method

Abstract

The application discloses a hydrogen leakage rapid detection device and method, and belongs to the hydrogen safety technical field.The device comprises a detection sealing cover, a micro-pressure difference sensor, a hydrogen concentration detection unit, a negative pressure maintaining system, an edge computing module and an alarm device.The detection sealing cover is composed of an upper half cover body and a lower half cover body which are mutually buckled, and a plurality of magnetic sealing ring half circles of different sizes are arranged at the two ends of the detection sealing cover and are connected through flexible rubber materials to adapt to pipelines, valves, flanges or joints of different specifications.The negative pressure maintaining system keeps the detection cavity in negative pressure and guides the leakage hydrogen to gather;the edge computing module starts hydrogen concentration detection according to the pressure difference change, judges the leakage state in combination with the detection result, and controls the alarm and related linkage devices.The application can reduce the influence of environmental airflow and hydrogen diffusion on detection, and improve the timeliness and reliability of leakage detection.

Description

Technical Field

[0001] This invention belongs to the field of hydrogen safety technology, specifically relating to a rapid detection device and method for hydrogen leaks in valves, pipe flanges, and other locations. Background Technology

[0002] With the rapid popularization of end-use applications such as hydrogen fuel cell vehicles and hydrogen refueling stations, hydrogen leak detection technology is facing unprecedented challenges and opportunities. The small molecular weight, rapid diffusion rate, and wide explosive limit range (4%-75%) of hydrogen make leak detection more difficult than for other gases. At every stage of the hydrogen energy industry chain, from hydrogen production and storage to end-use applications, more sensitive, faster, and more reliable leak monitoring methods are needed to ensure safe operation. However, existing detection technologies based on open environments are insufficient to meet the ever-increasing safety requirements, especially in early warning and precise location of minute leaks. Hydrogen has a low density and rapid diffusion rate. In ventilated or open environments, small amounts of leaked hydrogen are easily diluted rapidly, making them difficult for sensors to detect in a timely manner. Existing detection devices typically monitor the hydrogen concentration in the surrounding environment directly, and their detection effectiveness is easily affected by factors such as sensor installation location, ambient airflow, and leak direction.

[0003] Therefore, those skilled in the art are dedicated to developing a device that can form a relatively stable detection space near the leak location and perform centralized detection of leaked hydrogen, in order to improve detection speed and accuracy. Summary of the Invention

[0004] The purpose of this invention is to provide a rapid hydrogen leak detection device and method to solve the problems of hydrogen diffusion in open environments and the fact that detection is easily affected by ambient airflow and sensor installation location, making it difficult to detect and accurately judge trace leaks in a timely manner.

[0005] To achieve the above objectives, the present invention provides a rapid hydrogen leak detection device, comprising a detection sealing cover, a micro differential pressure sensor, a hydrogen concentration detection unit, a negative pressure maintenance system, an edge computing module, and an alarm device; the detection sealing cover is used to cover the part to be detected, such as a hydrogen pipeline, valve, flange, or joint, to form a detection cavity around the part to be detected; the detection sealing cover includes an upper half and a lower half that interlock, with multiple magnetic sealing rings of different sizes provided at both ends of the upper and lower half, and adjacent magnetic sealing rings are connected by a flexible rubber material; when the upper and lower half are interlocked, the magnetic sealing rings that match the size of the part to be detected attract each other to form a sealing ring, and the other magnetic sealing rings... A semi-circle is separated from the part to be tested and rests against both sides of the part to be tested, thus forming a detection sealing cover together with the flexible rubber material; a sealing strip or heat-melt sealing structure is provided at the joint between the upper and lower half of the cover to form a detachable sealed connection; the micro-differential pressure sensor is used to detect the pressure difference between the detection chamber and the external environment; the hydrogen concentration detection unit is set in the detection chamber; the negative pressure maintenance system is connected to the detection chamber to keep the detection chamber in a negative pressure state lower than that of the external environment; the edge computing module is connected to the micro-differential pressure sensor, the hydrogen concentration detection unit, the negative pressure maintenance system and the alarm device respectively, and is used to determine the hydrogen leakage status based on the pressure difference detection result and the hydrogen concentration detection result, and control the relevant devices to perform corresponding actions.

[0006] This invention also provides a rapid hydrogen leak detection method using the above-mentioned device, comprising: installing a detection sealing cover on the part to be detected, such as a hydrogen pipeline, valve, flange, or joint; fastening the upper and lower half of the cover around the part to be detected, so that the matching magnetic sealing ring half-circles attract each other and seal the joint through a sealing strip or heat-fusion sealing structure to form a detection cavity; using a negative pressure maintenance system to keep the pressure inside the detection cavity lower than the external ambient pressure; continuously detecting the pressure difference inside and outside the detection cavity using a micro-differential pressure sensor; when the pressure difference or pressure difference change meets the suspected leak conditions, activating the hydrogen concentration detection unit to detect the hydrogen concentration inside the detection cavity; determining the hydrogen leak status based on the hydrogen concentration, and controlling the alarm device and related linkage devices to perform corresponding actions.

[0007] Compared with existing technologies, this invention forms a relatively closed detection chamber around the area to be detected by a detection sealing cover, and uses negative pressure to guide leaked hydrogen gas to accumulate in the detection area. This reduces the impact of rapid hydrogen diffusion and external airflow on the detection results, improving the timeliness and reliability of hydrogen leak detection. The detection sealing cover uses multiple magnetic sealing rings of different sizes in combination with flexible rubber material, which can be adapted to different pipe diameters and installation locations, providing good flexibility and ease of installation. It is also easy to disassemble, reuse, and maintain. By combining pressure detection with hydrogen concentration detection, it can also judge the sealing status and leakage status, and realize alarm and safety linkage response based on the detection results.

[0008] The following will further explain the concept, specific structure, and technical effects of the present invention in conjunction with the accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the assembly of the detection sealing cover in a preferred embodiment of the present invention; Figure 2 This is a schematic diagram of the detection sealing cover after it has been installed at the pipe flange in a preferred embodiment of the present invention; Figure 3 This is a block diagram illustrating the detection principle in a preferred embodiment of the present invention. Detailed Implementation

[0010] The following description, with reference to the accompanying drawings, illustrates several preferred embodiments of the present invention to make its technical content clearer and easier to understand. The present invention can be embodied in many different forms, and the scope of protection of the present invention is not limited to the embodiments mentioned herein.

[0011] This embodiment provides a rapid hydrogen leak detection device, which mainly includes a detection sealing cover, a micro differential pressure sensor, a hydrogen concentration detection unit, a negative pressure maintenance system, and an edge computing module. The device is installed at locations prone to leakage, such as hydrogen valves, pipe flanges, or joints. By forming a relatively closed detection chamber, leaking hydrogen can accumulate within the chamber and be detected promptly.

[0012] like Figure 1 As shown, the inspection sealing cover includes an upper half cover 1 and a lower half cover 2 that are symmetrically arranged. Multiple magnetic sealing rings 3 are symmetrically arranged at both ends of the upper half cover 1 and the lower half cover 2. The multiple magnetic sealing rings 3 are arranged in sequence according to the commonly used pipe size specifications and are connected to each other by flexible rubber material 4.

[0013] like Figure 2As shown, when the flange 101 of the hydrogen pipeline 100 needs to be inspected, the upper half 1 and the lower half 2 of the inspection sealing cover are fastened together around the hydrogen pipeline 100. The magnetic sealing rings that are adapted to the size of the hydrogen pipeline 100 are automatically attracted to the pipeline under the action of magnetism to form a complete sealing ring. The smaller magnetic sealing rings are separated by the pipeline because they are smaller than the diameter of the pipeline 100 and cannot be attracted. They rest on the upper and lower sides of the pipeline. The larger magnetic sealing rings are attracted and act as a skeleton together with the flexible rubber material 4 to form the inspection sealing cover body. Then, the joint between the upper half 1 and the lower half 2 is sealed by the sealing strip 5. Alternatively, the joint can be sealed directly by high-temperature melting.

[0014] A micro differential pressure sensor is installed on the detection sealing cover to detect the pressure difference between the inside of the cover and the external environment. One end of the micro differential pressure sensor is connected to the detection chamber, and the other end is connected to the external environment. Its detection results are sent to the edge computing module. When the pressure difference or the rate of change of pressure difference inside the cover is abnormal, the edge computing module takes the abnormality as a suspected leakage signal and initiates hydrogen concentration detection.

[0015] The hydrogen concentration detection unit is housed within a sealed detection enclosure and includes a catalytic combustion hydrogen sensor and a TDLAS detection module. The catalytic combustion hydrogen sensor is used for rapid detection of low-concentration hydrogen, while the TDLAS detection module is used for detection and verification of higher-concentration hydrogen. During normal monitoring, the catalytic combustion hydrogen sensor is used preferentially; when its detection value exceeds 50 ppm, the TDLAS detection module is activated. The edge computing module compares the two detection results to determine the current hydrogen concentration and the sensor's operating status. When there is a significant discrepancy between the two detection results, the device issues a sensor malfunction warning and retains the detection data for operator review.

[0016] The negative pressure maintenance system is connected to the detection sealing cover and includes a miniature vacuum pump and a controller. During operation, the vacuum pump extracts gas from the detection chamber, maintaining a pressure inside the cover lower than the external environment. The controller adjusts the vacuum pump based on data from a micro-differential pressure sensor, maintaining the working negative pressure inside the detection chamber at -10 to -5 Pa. This negative pressure does not require a vacuum environment; its function is to guide leaked hydrogen into the detection chamber and towards the detection area, while simultaneously reducing hydrogen diffusion outward from the cover's connection points.

[0017] The edge computing module connects to the differential pressure sensor, hydrogen concentration detection unit, negative pressure maintenance system, and alarm device to receive detection data, determine leakage status, and control the operation of related equipment. The edge computing module can also connect to the monitoring center wirelessly to transmit hydrogen concentration, alarm status, and equipment operating status to the monitoring center.

[0018] When installing this device, first clean away debris and oil stains around valves, flanges, or joints. Then, adjust the detection sealing cover according to the shape of the part to be tested, ensuring it covers the connection points where leaks may occur. Next, secure the cover using a magnetic sealing ring or other fixing structure, and check the fit between the cover and the equipment surface. After installation, connect the vacuum pump, sensor, alarm device, and communication lines, and start the negative pressure maintenance system.

[0019] After the device is started, the vacuum pump first adjusts the pressure inside the detection chamber to the set range. The micro differential pressure sensor continuously collects the pressure difference between the inside and outside of the enclosure, and the edge computing module determines whether the enclosure is in normal working condition based on the pressure difference data. When the rate of change of pressure difference reaches the set condition, such as not less than 0.2 Pa / s, the edge computing module determines that there may be a gas leak inside the detection chamber and activates the catalytic combustion hydrogen sensor for detection.

[0020] If the catalytic combustion hydrogen sensor does not detect hydrogen, or if the detected concentration is below the set alarm value, the device remains in monitoring mode. If the detected concentration reaches the alarm value, the edge computing module controls the audible and visual alarm device to issue an alarm and uploads the detection results to the monitoring center.

[0021] When the catalytic combustion hydrogen sensor detects a value greater than 50 ppm, the edge computing module activates the TDLAS detection module for verification. If both sensors indicate the presence of hydrogen, the edge computing module determines the leak level based on the detected concentration. The specific processing method for the detection results can be configured according to the safety requirements of the application environment.

[0022] In this embodiment, when the hydrogen concentration is not higher than 100 ppm, the device issues an audible and visual alarm and continues to monitor the concentration change; when the hydrogen concentration is greater than 100 ppm but not higher than 1000 ppm, in addition to issuing an alarm, it also controls the upstream hydrogen solenoid valve to close to cut off the gas source; when the hydrogen concentration is greater than 1000 ppm, while closing the upstream hydrogen solenoid valve, the emergency exhaust valve is opened and the nitrogen purging device is started.

[0023] The emergency exhaust valve is connected to the exhaust pipe leading to a safe area to prevent emitted hydrogen from entering areas with personnel or other potential ignition sources. A nitrogen purging device is connected to the inlet of the detection sealing cover to reduce the hydrogen concentration within the detection chamber. During exhaust and purging, the hydrogen concentration detection unit continues to operate. Once the detected hydrogen concentration is below the safe level and remains stable for a period of time, the edge computing module shuts off the emergency exhaust valve and nitrogen purging device and sends a completion notification to the monitoring center. Restoration of upstream gas supply is carried out by personnel only after confirming that the leak has been eliminated; the device does not automatically restore gas supply directly.

[0024] To check the sealing condition of the detection cover, this device can also perform a periodic self-test. During the self-test, the negative pressure maintenance system reduces the pressure inside the cover to approximately -15 Pa, then shuts off the vacuum pump. The micro-differential pressure sensor records the time required for the pressure inside the cover to rise back to -5 Pa. If the pressure rises too quickly, for example, if the rise time is less than 30 seconds, it indicates that there may be a large gap between the detection cover and the equipment. The edge computing module will issue a sealing abnormality alarm, prompting personnel to check the cover, magnetic sealing ring, and connecting pipelines.

[0025] After installation, the hydrogen concentration detection unit can be calibrated using standard hydrogen gas, and the alarm, solenoid valve, emergency exhaust valve, and nitrogen purging device can be checked for proper operation through simulated leak testing. After commissioning, the device enters continuous monitoring mode.

[0026] In other embodiments, the fixing method of the detection sealing cover can be changed to clamps, straps, or mechanical locks, depending on the equipment material and installation conditions; the hydrogen concentration detection unit can also use other sensors suitable for hydrogen detection. The negative pressure range, alarm concentration, and linkage conditions can be adjusted according to the detection site, equipment pressure, and relevant safety regulations. The above adjustments do not change the basic working principle of using the detection sealing cover to limit hydrogen diffusion, guiding leaked gas through negative pressure, and taking linkage actions based on the detection results.

[0027] In the accompanying drawings, components with the same structure are indicated by the same numerical designation, and components with similar structures or functions are indicated by similar numerical designations. The dimensions and thicknesses of each component shown in the drawings are arbitrary, and the present invention does not limit the dimensions and thicknesses of each component. To make the illustrations clearer, the thickness of some components has been appropriately exaggerated in the drawings.

[0028] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A rapid detection device for hydrogen leaks, characterized in that, The system includes a detection sealing cover, a micro-differential pressure sensor, a hydrogen concentration detection unit, a negative pressure maintenance system, an edge computing module, and an alarm device. The detection sealing cover is used to cover the area to be tested, such as hydrogen pipelines, valves, flanges, or joints, to form a detection cavity around the area. The detection sealing cover consists of an upper and lower half that interlock. Multiple magnetic sealing rings of different sizes are installed at both ends of the upper and lower half, and adjacent magnetic sealing rings are connected by a flexible rubber material. After the upper and lower half are interlocked, the magnetic sealing rings adapted to the size of the hydrogen pipeline attract each other to form a sealing ring. Magnetic sealing rings smaller than the diameter of the hydrogen pipeline are... The hydrogen pipelines are separated and cannot be attracted to each other, and are respectively placed on the upper and lower sides of the hydrogen pipelines; the magnetic sealing rings, which are larger than the diameter of the hydrogen pipelines, are attracted to each other to form a skeleton, and together with the flexible rubber material connected to it, they form the body of the detection sealing cover; the joint between the upper and lower half of the cover is provided with a sealing strip, or is sealed by heat fusion sealing, so that the detection sealing cover and the part to be detected form a detachable sealing connection; a micro differential pressure sensor is used to detect the pressure difference between the detection chamber and the external environment; the hydrogen concentration detection unit is set in the detection chamber; the negative pressure maintenance system is connected to the detection chamber to keep the detection chamber in a negative pressure state lower than that of the external environment; The edge computing module is connected to the differential pressure sensor, hydrogen concentration detection unit, negative pressure maintenance system and alarm device respectively. It is used to determine the hydrogen leakage status based on the pressure difference detection result and hydrogen concentration detection result, and control the negative pressure maintenance system and alarm device to operate.

2. The rapid hydrogen leak detection device according to claim 1, characterized in that, The hydrogen concentration detection unit includes a catalytic combustion hydrogen sensor and a TDLAS detection module. The catalytic combustion hydrogen sensor is used for rapid detection of hydrogen concentration, while the TDLAS detection module is used for detection of higher concentrations of hydrogen or for verification of the detection results of the catalytic combustion hydrogen sensor.

3. The rapid hydrogen leak detection device according to claim 1, characterized in that, The negative pressure maintenance system includes a miniature vacuum pump and a controller. The controller adjusts the miniature vacuum pump based on the pressure difference data fed back by the micro-pressure differential sensor to maintain the working negative pressure in the detection chamber within the range of -10 Pa to -5 Pa.

4. The rapid hydrogen leak detection device according to claim 1, characterized in that, When the edge computing module detects that the rate of change of the pressure difference between the inside and outside of the detection chamber reaches a set condition, it determines that there may be a gas leak in the detection chamber and activates the hydrogen concentration detection unit to detect the hydrogen concentration.

5. The rapid hydrogen leak detection device according to claim 2, characterized in that, When the hydrogen concentration detected by the catalytic combustion hydrogen sensor is greater than 50 ppm, the edge computing module activates the TDLAS detection module for verification, and determines the hydrogen leak status and leak level when both detection results indicate the presence of hydrogen.

6. The rapid hydrogen leak detection device according to claim 1, characterized in that, It also includes an upstream hydrogen solenoid valve, an emergency exhaust valve, and a nitrogen purging device connected to the edge computing module; the emergency exhaust valve is connected to the exhaust pipe leading to the safe area, and the nitrogen purging device is connected to the air inlet of the detection chamber; when the detected hydrogen concentration is greater than a first set value, the edge computing module controls the upstream hydrogen solenoid valve to close; when the detected hydrogen concentration is greater than a second set value, the edge computing module closes the upstream hydrogen solenoid valve, opens the emergency exhaust valve, and starts the nitrogen purging device.

7. A rapid detection method for hydrogen leaks, characterized in that, include: A detection sealing cover is installed on the hydrogen pipeline, valve, flange, or joint to be tested. The detection sealing cover includes an upper half, a lower half, and multiple magnetic sealing ring halves of different sizes located at both ends of the upper and lower half. The upper and lower half are fastened around the part to be tested, so that the two magnetic sealing ring halves that are adapted to the size of the part to be tested attract each other to form a sealing ring. The joint is sealed by a sealing strip or a heat-fusion sealing structure located at the joint of the upper and lower half to form a detection chamber covering the part to be tested. The pressure in the detection chamber is adjusted to be lower than the external ambient pressure by a negative pressure maintenance system. The pressure difference between the detection chamber and the external environment is continuously monitored by a micro differential pressure sensor. When the pressure difference or the rate of change of the pressure difference meets the suspected leakage conditions, the hydrogen concentration detection unit is activated to detect the hydrogen concentration in the detection chamber. The leakage state and leakage level are determined according to the hydrogen concentration, and at least one of the following is controlled to perform corresponding actions: alarm device, upstream hydrogen solenoid valve, emergency exhaust valve, and nitrogen purging device.

8. The rapid detection method for hydrogen leakage according to claim 7, characterized in that, Multiple magnetic sealing ring halves of different sizes are arranged sequentially according to the common specifications of the pipe to be tested. Adjacent magnetic sealing ring halves are connected by flexible rubber material. When the upper and lower half of the cover are fastened together, the magnetic sealing ring halves smaller than the outer diameter of the pipe to be tested are separated by the pipe to be tested, while the magnetic sealing ring halves that are adapted to the outer diameter of the pipe to be tested attract each other and together with the flexible rubber material form a test sealing cover.

9. The rapid detection method for hydrogen leakage according to claim 7, characterized in that, The hydrogen concentration detection unit includes a catalytic combustion hydrogen sensor and a TDLAS detection module. When the hydrogen concentration detected by the catalytic combustion hydrogen sensor is greater than 50 ppm, the TDLAS detection module is activated for verification. When both detection results indicate the presence of hydrogen, the leakage level is determined based on the hydrogen concentration. Specifically, when the hydrogen concentration is greater than a first set value, the upstream hydrogen solenoid valve is closed; when the hydrogen concentration is greater than a second set value, the upstream hydrogen solenoid valve is closed, the emergency exhaust valve is opened, and the nitrogen purging device is activated.

10. The rapid detection method for hydrogen leakage according to claim 7, characterized in that, It also includes a self-test for the sealing cover, which includes: reducing the pressure in the detection chamber to the set negative pressure through the negative pressure maintenance system and then turning off the vacuum pump; recording the time required for the pressure in the detection chamber to rise back to the preset pressure through the micro differential pressure sensor; and determining that there is a sealing abnormality in the detection cover when the time is less than the set time threshold and issuing a sealing abnormality alarm.

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