A hydrogen leak detection and localization system

Abstract

The application belongs to the technical field of hydrogen safety monitoring, and specifically relates to a hydrogen leakage detection and positioning system.The system comprises a hydrogen leakage far-field detection unit array, a data platform and a hydrogen leakage on-site attached detection unit.The far-field detection unit array is composed of multiple wireless hydrogen sensors and a leakage hydrogen collection device, is used for remotely and timely detecting the hydrogen concentration of a hydrogen system to be detected, and sends the detected hydrogen concentration and the corresponding detection unit number to the data platform;the data platform determines the hydrogen leakage position accordingly;the hydrogen leakage on-site attached detection unit is arranged in the detection range of each far-field detection unit, is attached to a key position with a relatively high leakage probability in the hydrogen system to be detected, and realizes visual detection of hydrogen leakage;the system can improve the safety, accuracy and cost-effectiveness of hydrogen leakage monitoring, and is suitable for various application scenarios such as hydrogen refueling stations and hydrogen energy production and storage sites.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of hydrogen safety monitoring, and particularly relates to a hydrogen leakage detection and positioning system. BACKGROUND

[0002] With the rapid development of hydrogen energy industry, hydrogen, as a clean energy, has been widely used in many fields. However, due to the highly flammable and explosive characteristics of hydrogen, once it encounters a fire source when the volume fraction in air is more than 4.0% to 75.6%, it may cause an explosion. This characteristic is particularly prominent in the production, transportation, storage and refueling process of hydrogen. In addition, hydrogen has low viscosity and high diffusion speed, so it is easy to leak, which makes the hydrogen leakage problem particularly serious. Once leakage occurs, it will seriously threaten personnel safety and equipment stability, and may also cause significant economic losses.

[0003] Due to the large number of potential leakage points in the hydrogen system, it is challenging to achieve safe and global hydrogen leakage detection. The causes of leakage accidents are various, mainly including problems at joints, welding, pipe rupture, design defects and improper human operation, etc. Among them, the leakage probability at the joint is the highest, accounting for more than 50%. Although general hydrogen sensors can be arranged to detect these potential leakage points point by point to achieve accurate positioning, this method is costly, and each sensor contains a circuit battery, which may cause sparks, thereby bringing safety risks.

[0004] Generally, hydrogen sensors are placed on the top of a certain distance above the hydrogen system or the top of the place, aiming to expand their detection range. However, this approach not only makes it difficult to accurately locate the leakage point, but also, once hydrogen leaks and diffuses upwards, its concentration may decrease. In addition, the detection range of general hydrogen sensors is limited, which makes the sensor unable to detect in time and effectively, thereby increasing the risk of hydrogen explosion.

[0005] In summary, the existing hydrogen monitoring methods generally have low safety, low efficiency, inaccurate positioning and high cost, etc., which are difficult to meet user needs. Therefore, it is particularly important to develop a hydrogen leakage monitoring system and method that is safe, efficient, accurate and low-cost, which will effectively promote the popularization and application of hydrogen energy. SUMMARY

[0006] The purpose of the present application is to provide a hydrogen leakage detection and positioning system to achieve rapid response and accurate positioning of hydrogen leakage, and to improve the safety and accuracy of monitoring.

[0007] The hydrogen leakage detection and positioning system provided by the application combines the intuitive visual detection function of the safe and economical hydrogen color-changing transparent film and the remote real-time monitoring function of the wireless hydrogen sensor, realizes rapid response and accurate positioning of hydrogen leakage, and specifically comprises: a hydrogen leakage far-field detection unit array, a data platform, and a hydrogen leakage on-site attached detection unit.

[0008] The hydrogen leakage far-field detection unit array is connected with the data platform, and is composed of N wireless hydrogen sensors and a leakage hydrogen collection device (N>1) with numbers, is used for detecting the hydrogen concentration on the upper part of a hydrogen system to be detected, and sends the detected hydrogen concentration and the corresponding hydrogen leakage far-field detection unit number to the data platform.

[0009] The hydrogen leakage on-site attached detection unit is provided with one or more hydrogen leakage on-site attached detection units based on the hydrogen color-changing transparent film, is attached to key parts such as joints and welding points with a high leakage probability in the hydrogen system to be detected, and is arranged at different spatial positions of the hydrogen system to realize visual detection of hydrogen leakage.

[0010] The hydrogen leakage on-site attached detection unit specifically adopts a transparent film with a hydrogen color-changing function, that is, the transparent film changes color with the change of the hydrogen concentration.

[0011] The hydrogen leakage detection and positioning system can further comprise an alarm device, which is connected with the data platform, determines the hydrogen leakage position in the hydrogen system to be detected according to the data platform, and alarms hydrogen leakage. Once hydrogen leakage is found, an alarm is immediately given and relevant personnel are notified to go to the leakage position. The alarm can be given in the form of sound and light alarm, short message and telephone notification, etc.

[0012] The hydrogen leakage far-field detection unit mainly comprises the following parts: a leakage hydrogen collection device, which is used for capturing and collecting the leaked trace hydrogen; a hydrogen sensor, which is used for detecting the hydrogen concentration; and a data signal wireless transmission module, which is used for sending relevant data to the data platform in a wireless transmission mode.

[0013] The hydrogen leakage collection device is shaped like an upside-down funnel, with a wider bottom and a narrower top. The top of the device is designed with a space containing a leak hole, and the hydrogen sensor is installed inside the space. The collection device can capture and collect the leaked hydrogen, thereby increasing the hydrogen concentration in the top space, making it easier for the sensor to monitor the leaked hydrogen.

[0014] An automatic exhaust valve is installed above the top space of the hydrogen leakage collection device. When the hydrogen concentration at the top of the collection device exceeds the set concentration (usually 4%), the valve will automatically open to release hydrogen.

[0015] The lower end of the hydrogen leakage collection device can be shaped in various ways, including but not limited to square, rectangular, triangular, oval, and circular.

[0016] The hydrogen sensor can be of various types, including but not limited to optical hydrogen sensor, semiconductor metal oxide hydrogen sensor, electrochemical hydrogen sensor, thermal conductivity hydrogen sensor, and catalytic hydrogen sensor.

[0017] Further, the optical hydrogen sensor is composed of a hydrogen color-changing transparent film, a light source, and a light receiver.

[0018] The hydrogen color-changing transparent film can be a tungsten oxide film, a magnesium-based alloy film, or other metal oxide film.

[0019] The light source can be a visible light source, a specific wavelength visible light source, or a near-infrared light source.

[0020] The light receiver can be a corresponding visible light receiver, near-infrared light receiver, etc.

[0021] In further optimized design, the light receiver can be one or two. Preferably, two light receivers are selected to reduce the interference of external factors such as light and temperature, and to improve the stability of the sensor.

[0022] Further, the hydrogen sensing component of the optical hydrogen sensor and the data signal wireless transmission module can be designed as a separate type.

[0023] The hydrogen leakage site attachment detection unit is mainly composed of a hydrogen color-changing transparent film and a semi-closed transparent cavity. The top of the cavity is designed with a small hole, which is used to discharge hydrogen upwards and ensure that external hydrogen cannot flow into the cavity. The hydrogen color-changing transparent film is installed inside the cavity, and its main function is to collect leaked hydrogen and change its color by reacting with hydrogen.

[0024] Further, the hydrogen gas color-changing transparent film can be selected from tungsten oxide film, magnesium-based alloy film and other metal oxide film materials. These oxide films are plated on one side of the transparent substrate or inside the transparent cavity, and the plating surface is the side exposed to hydrogen gas.

[0025] The workflow of the system is as follows:

[0026] When the hydrogen gas leakage far-field detection unit detects that the hydrogen gas system to be detected has a hydrogen gas leakage, the data platform calls the stored number and corresponding position information of the hydrogen gas leakage far-field detection unit according to the hydrogen gas concentration detected by the hydrogen gas leakage far-field detection unit and the corresponding number of the hydrogen gas leakage far-field detection unit, determines the hydrogen gas concentration center position information of the hydrogen gas leakage far-field detection unit through interpolation operation; the relevant personnel determine the exact position of the hydrogen gas leakage of the hydrogen gas system to be detected according to the hydrogen gas concentration center position information and the color-changing information of the attached detection unit.

[0027] The system can significantly improve the safety, efficiency and accuracy of monitoring, and bring better cost-effectiveness.

[0028] The present application has the following application prospects:

[0029] Real-time detection of hydrogen gas leakage and accurate positioning of the leakage point for hydrogen refueling stations;

[0030] Real-time detection of hydrogen gas leakage and accurate positioning of the leakage point for hydrogen energy production, storage and use sites;

[0031] For hydrogen energy vehicles, trucks, airplanes, ships, etc.

[0032] Real-time detection of hydrogen gas leakage and accurate positioning of the leakage point for hydrogen cylinder explosion-proof cabinets. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 The figure is a structural schematic diagram of the hydrogen gas leakage detection and positioning system of the present application.

[0034] Figure 2 The figure is a simulation layout diagram of the hydrogen gas leakage detection and positioning system of the present application.

[0035] Figure 3 The figure is a structural schematic diagram of the leakage hydrogen gas collection device of the embodiment of the present application.

[0036] Figure 4 The figure is a structural schematic diagram of the wireless optical hydrogen gas sensor of the embodiment of the present application.

[0037] Figure 5 The figure is a structural schematic diagram of the hydrogen gas leakage on-site attached detection unit of the embodiment of the present application.

[0038] Figure 6The hydrogen leakage detection and positioning method flowchart of the embodiment of the present application. DETAILED DESCRIPTION

[0039] The present application will be further described below by way of examples in conjunction with the accompanying drawings.

[0040] The hydrogen leakage detection and positioning system provided by the present application, for its structure, please refer to Figure 1 The array formed by one or more wireless hydrogen leakage far-field detection units with numbers, hydrogen leakage on-site attached detection units and a data platform. Among them, the hydrogen leakage far-field detection units are wirelessly connected with the data platform, and are respectively arranged within a certain distance range above the hydrogen system to be detected, for detecting the hydrogen concentration within a certain range above the hydrogen system to be detected, and sending the detected hydrogen concentration and the corresponding hydrogen leakage far-field detection unit number to the data platform.

[0041] The data platform stores all hydrogen leakage far-field detection unit numbers and corresponding position information, for determining the hydrogen leakage position in the hydrogen system to be detected according to the received hydrogen concentration and the corresponding hydrogen leakage far-field detection unit number.

[0042] The hydrogen system to be detected includes hydrogen pipeline system, storage system, filling system, etc. The hydrogen / liquid hydrogen leakage may occur at the places where the pipeline joints, welding points, etc. are installed, which are prone to leakage, or at the places such as pipeline surface, tank surface, hydrogen filling port, hydrogen compressor, etc. As shown in Figure 2 After the hydrogen system to be detected is installed, a plurality of hydrogen leakage attached detection units are installed at the places where the pipeline joints, welding points, etc. are prone to leakage, and a hydrogen leakage far-field detection array is installed at a certain distance above the hydrogen pipeline or storage system. Each hydrogen leakage far-field detection unit has a specific number and position information, and its number and position information are stored in the data platform.

[0043] The hydrogen leakage far-field detection unit mainly consists of the following parts: a leakage hydrogen collection device, which is used to capture and collect the leaked trace hydrogen to increase the hydrogen concentration at the top of the device, thereby facilitating the detection of the leaked hydrogen; a hydrogen sensor, which functions to detect the hydrogen concentration; and a data signal wireless transmission module, such as Bluetooth, Wi-Fi, Zigbee, etc., which functions to send relevant data to the data platform of the hydrogen leakage detection and positioning system through wireless transmission.

[0044] The shape feature of the hydrogen leakage collection device is that the lower part is wider and gradually narrows upwards, like an inverted funnel. After hydrogen leaks, it will diffuse upwards, and its concentration may decrease, and the diffusion speed is faster, which often leads to that the sensor cannot timely and effectively detect the leaked hydrogen. Therefore, the uppermost end of the collection device is specially designed with a space with a hole at the bottom, and a hydrogen sensor is installed inside the space. By using the characteristic that the mass of hydrogen is lighter than that of air, the device can effectively capture and collect the leaked trace hydrogen, separate hydrogen from air, increase the hydrogen concentration in the top space, and make the leaked hydrogen more easily detected by the sensor. Through this design, the leaked hydrogen collection device can significantly expand the detection range of the hydrogen sensor.

[0045] Further, an automatic exhaust valve is installed above the top space of the leaked hydrogen collection device. When the hydrogen concentration at the top of the device exceeds the set concentration (usually set to 4%), the valve will automatically open to discharge hydrogen, so as to ensure that the collected hydrogen does not pose a safety hazard.

[0046] Further, the lower end of the leaked hydrogen collection device can be diversified, including but not limited to square, rectangular, triangular, oval, and circular, etc. One structure of the leaked hydrogen collection device is shown in Figure 3 (a) and (b).

[0047] The hydrogen sensor can be of various types, including but not limited to optical hydrogen sensor, semiconductor metal oxide hydrogen sensor, electrochemical hydrogen sensor, thermal conductivity hydrogen sensor, and catalytic hydrogen sensor, etc.

[0048] Further, as shown in Figure 4 , the optical hydrogen sensor mainly consists of tungsten oxide transparent film, light source, and light receiver. Its detection principle is based on the characteristic that hydrogen can change the transparency of the film, and by using the light source and light receiver to monitor the change of the film transmittance, the detection of hydrogen concentration is realized.

[0049] Further, the hydrogen color-changing transparent film can be tungsten oxide film, magnesium-based alloy film, and other metal oxide films. These films will change in transparency under hydrogen environment, providing detection signals for the sensor.

[0050] In addition, the light source can be a visible light source, a specific wavelength light source, or a near-infrared light source, etc., and the appropriate type of light source is selected according to the actual needs.

[0051] At the same time, the light receiver can be a visible light receiver, a near-infrared light receiver, etc., for receiving and converting optical signals into electrical signals.

[0052] In further optimization design, the light receiver can be one or two. Two light receivers are preferred, one of which is used to detect the change of light transmittance of tungsten oxide, and the other is used to provide a reference value. The change of hydrogen concentration is represented by the ratio of the two light receivers, which can reduce the interference of external factors such as light and temperature, and improve the stability of the sensor.

[0053] Finally, the hydrogen sensing part and the data signal wireless transmission module of the optical hydrogen sensor can be designed as a separate type. In this way, after a period of use, the hydrogen sensing part can be replaced directly without calibration, thereby reducing the maintenance and use cost of the sensor.

[0054] The hydrogen leakage attachment detection unit is mainly composed of a hydrogen color-changing transparent film and a semi-closed transparent cavity. A small hole is designed at the top of the cavity, which is used to discharge hydrogen upwards and ensure that external hydrogen cannot flow back into the cavity. Inside the cavity, a hydrogen color-changing transparent film is installed, which mainly functions to collect leaked hydrogen and change its color by reacting with hydrogen. The hydrogen leakage attachment detection unit can be installed in cooperation with the parts prone to leakage such as hydrogen pipeline joints and welding points. A structure of the hydrogen leakage attachment detection unit is shown in (a) and (b) of Figure 5

[0055] The hydrogen color-changing transparent film can be made of tungsten oxide film, magnesium-based alloy film, or other metal oxide film materials. These oxide films are plated on one side of the transparent substrate or inside the transparent cavity, and the plated side is exposed to hydrogen.

[0056] In an embodiment of the present application, when the hydrogen leakage of the hydrogen gas system to be detected is detected by the hydrogen leakage far-field detection unit, the data platform calls the position information corresponding to the number of the hydrogen leakage far-field detection unit according to the hydrogen concentration detected by the hydrogen leakage far-field detection unit and the unit number, and determines the hydrogen leakage position of the hydrogen gas system to be detected by interpolation operation.

[0057] In an embodiment of the present application, the system further comprises an alarm device connected to the data platform of the hydrogen leakage detection and positioning system, which is used to alarm the hydrogen concentration according to the hydrogen leakage position of the hydrogen gas system to be detected determined by the data platform of the hydrogen leakage detection and positioning system. Once hydrogen leakage is found, an alarm is immediately sent and relevant personnel are notified to go to the leakage site. The alarm can be sent through sound and light alarm, short message and telephone notification, etc.

[0058] ​Specifically, the alarm device can be an alarm device comprising a display screen, through which the position of the hydrogen leakage and the hydrogen concentration are displayed for the user to view, and the alarm device also comprises an audible and visual alarm device, such as a buzzer and an indicator light, to prompt the user through sound and light to find the hydrogen leakage in time and avoid danger.

[0059] When the hydrogen leakage occurs at a position where the hydrogen color-changing transparent film attachment detection unit is not installed, the relevant personnel judge whether the hydrogen leakage position is deviated according to the wind speed, wind direction, temperature and humidity of the surrounding environment; if yes, the hydrogen leakage position information is corrected, and if no, the relevant personnel detect the surface of the pipeline outside the attachment detection unit by using a portable hydrogen sensor and soap water and the like to find out the potential leakage point; so as to realize the positioning of the hydrogen leakage position.

[0060] The detailed flow of the positioning method of the hydrogen leakage detection and positioning system of the application is shown in the attached Figure 6 , and the specific steps are as follows:

[0061] (1) detecting whether there is a condition that the hydrogen concentration of the far-field unit is greater than the threshold value (less than 4%); if yes, go to the second step;

[0062] (2) reading the number and position information of all far-field units with hydrogen concentration greater than the threshold value, and determining the hydrogen leakage position information through interpolation operation;

[0063] (3) issuing a hydrogen leakage alarm and notifying the relevant personnel to go to the hydrogen leakage position;

[0064] (4) the relevant personnel check whether the color of the attachment detection unit near the hydrogen leakage position changes, if yes, go to step (5), and if no, go to step (6);

[0065] (5) the position of the attachment detection unit with color change is the hydrogen leakage position, and go to step (9);

[0066] (6) the relevant personnel judge whether the hydrogen leakage position is deviated according to the wind speed, wind direction, temperature and humidity of the surrounding environment; if yes, go to step (7), and if no, go to step (8);

[0067] (7) correct the hydrogen leakage position information, and go to step (4);

[0068] (8) the relevant personnel detect the surface of the pipeline outside the attachment detection unit by using a portable hydrogen sensor and soap water and the like to find out the potential leakage point;

[0069] (9) the relevant personnel repair the hydrogen leakage point, open the exhaust valve of the hydrogen leakage collection device, remove the hydrogen in the device, and ensure that the hydrogen sensor data is zeroed.

[0070] (10) Determine whether to stop working; if yes, cancel the alarm and end; if no, go to step (1).

[0071] According to the hydrogen leakage detection and positioning method, by arranging a plurality of wireless hydrogen sensor arrays with wide range detection capability above the hydrogen system as a far field detection device for hydrogen leakage, real-time detection of far field hydrogen leakage is realized. At the same time, safe and economical hydrogen color-changing transparent film detection devices are arranged at the joints, welding points and other parts with high leakage probability in the hydrogen system, realizing the visual detection of the attached hydrogen leakage. The present application effectively solves the problems of low safety, low efficiency, inaccurate positioning and high cost of the existing hydrogen leakage detection system, especially in the case of large hydrogen system site and many potential leakage points, realizing fast and global detection of hydrogen leakage. In addition, the method also realizes rapid response and accurate positioning of hydrogen leakage, significantly improves the safety and accuracy of monitoring, and brings better cost effectiveness.

Claims

1. A hydrogen gas leak detection and localization system, comprising: The application discloses a visual detection function of a safety and economical hydrogen gas color-changing transparent film and a remote real-time monitoring function of a wireless hydrogen gas sensor, and realizes rapid response and accurate positioning of hydrogen gas leakage. The hydrogen gas leakage remote field detection unit array is connected with the data platform; the hydrogen gas leakage remote field detection unit array is composed of N wireless hydrogen gas sensors with numbers and a leakage hydrogen gas collecting device (N>=1), is used for detecting hydrogen gas concentration of a hydrogen gas system to be detected, and sends the detected hydrogen gas concentration and a corresponding hydrogen gas leakage remote field detection unit number to the data platform; the data platform stores all numbers of the hydrogen gas leakage remote field detection units and corresponding position information, is used for determining a hydrogen gas leakage position in the hydrogen gas system to be detected according to the received hydrogen gas concentration and the corresponding hydrogen gas leakage detection unit number. The hydrogen gas leakage on-site attached detection unit is arranged in the detection range of each remote field detection unit and is attached to a key position with a relatively large leakage probability in the hydrogen gas system to be detected; a plurality of such attached detection units are arranged at different spatial positions of the hydrogen gas system to realize visual detection of hydrogen gas leakage. The hydrogen gas leakage on-site attached detection unit specifically adopts a transparent film with a hydrogen gas color-changing function, that is, the transparent film changes color with the change of hydrogen gas concentration. The hydrogen gas leakage remote field detection unit is composed of the following parts: a leakage hydrogen gas collecting device, a hydrogen gas sensor and a data signal wireless transmission module; the leakage hydrogen gas collecting device is used for capturing and collecting leaked trace hydrogen gas; the hydrogen gas sensor is used for detecting hydrogen gas concentration; the data signal wireless transmission module sends relevant data to the data platform through wireless transmission; wherein: The hydrogen gas leakage collecting device is shaped like an inverted funnel with a wider lower part and a gradually narrowing upper part; the upper end of the collecting device is designed with a space with a hole at the bottom, and the hydrogen gas sensor is installed inside the space; the collecting device can collect leaked trace hydrogen gas, thereby increasing the hydrogen gas concentration of the top space of the collecting device, so that the hydrogen gas is more easily monitored by the hydrogen gas sensor; An automatic exhaust valve is installed above the top space of the leakage hydrogen gas collecting device; when the hydrogen gas concentration at the top of the collecting device exceeds a set concentration, the valve is automatically opened to discharge hydrogen gas; The hydrogen gas leakage attached detection unit is composed of a hydrogen gas color-changing transparent film and a semi-closed transparent cavity, and the hydrogen gas color-changing transparent film is installed inside the cavity; the top of the semi-closed transparent cavity is designed with a small hole for discharging hydrogen gas upward and ensuring that external hydrogen gas cannot flow back into the cavity; the cavity is used for collecting and detecting leaked hydrogen gas and changing its own color by reacting with hydrogen gas.

2. The hydrogen leak detection and localization system of claim 1, wherein, The hydrogen gas sensor adopts an optical hydrogen gas sensor, a semiconductor metal oxide hydrogen gas sensor, an electrochemical hydrogen gas sensor, a thermal conductivity hydrogen gas sensor or a catalytic hydrogen gas sensor.

3. The hydrogen leak detection and localization system of claim 2, wherein, The optical hydrogen gas sensor is composed of a hydrogen gas color-changing transparent film, a light source and a light receiver; wherein: The hydrogen gas color-changing transparent film adopts a tungsten oxide film or a magnesium-based alloy film. The light source adopts a visible light source, a visible light source of specific wavelength or a near-infrared light source; The light receiver adopts a corresponding visible light receiver or a near-infrared light receiver.

4. The hydrogen leak detection and localization system of claim 2, wherein, The hydrogen sensing part and the data signal wireless transmission module of the optical hydrogen sensor are designed in a separated mode.

5. The hydrogen leak detection and localization system of claim 4, wherein, The hydrogen gas discoloring transparent film in the hydrogen leakage attaching detection unit adopts a tungsten oxide film or a magnesium-based alloy film; the film is plated on one side of a transparent substrate or inside a transparent cavity, and the plated film is exposed to the side of the leaked hydrogen gas.

6. The hydrogen leak detection and localization system of any of claims 1-5, wherein, The alarm device is connected with the data platform, determines the hydrogen leakage position in the hydrogen system to be detected according to the data platform, and alarms the hydrogen concentration.

7. The hydrogen leak detection and localization system of any of claims 1-5, wherein, The working process is as follows: When the hydrogen leakage remote field detection unit detects the hydrogen leakage of the hydrogen system to be detected, the data platform calls the stored number and corresponding position information of the hydrogen leakage remote field detection unit according to the hydrogen concentration detected by the hydrogen leakage remote field detection unit and the corresponding number of the hydrogen leakage remote field detection unit, determines the hydrogen concentration center position information of the hydrogen leakage remote field detection unit through interpolation operation; The related personnel determine the exact position of the hydrogen leakage of the hydrogen system to be detected according to the hydrogen concentration center position information and the discoloring information of the attaching detection unit.

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