A flexible thin film hydrogen sensitive sensor and hydrogen leakage monitoring and protection system

Abstract

The present invention relates to the technical field of hydrogen safety protection, and discloses a flexible thin-film hydrogen-sensitive sensor and a hydrogen leakage monitoring and protection system. The flexible thin-film hydrogen-sensitive sensor includes a proton exchange membrane and a plurality of hydrogen-sensitive sensing elements arranged in an array on the proton exchange membrane. Each hydrogen-sensitive sensing element is composed of a counter electrode and a sensing electrode correspondingly arranged on both sides of the proton exchange membrane, and a catalytic layer is coated on the proton exchange membrane. The hydrogen leakage monitoring and protection system includes the above-mentioned flexible thin-film hydrogen-sensitive sensor. The flexible thin-film hydrogen-sensitive sensor is an array of electrochemical hydrogen-sensitive sensing elements, and the spacing and number of hydrogen-sensitive sensing elements are determined according to the required positioning accuracy. When hydrogen leaks, the hydrogen leak is quickly and accurately located according to the voltage data of the sensing element and the time data of the voltage generation. The present invention utilizes the principle of electrochemical reaction to catalyze the hydrogen to be detected to generate an electrical signal, and the electrical signal measurement response time is below the millisecond level, thereby achieving a rapid response to hydrogen leaks at low concentrations.

Description

Technical Field

[0001] The invention belongs to the technical field of hydrogen safety protection and relates to a hydrogen leakage monitoring and protection system of a flexible film type hydrogen sensitive sensor. Background Art

[0002] Hydrogen is a colorless and odorless gas. Due to its small molecular size and strong permeability, it is easy to cause leakage or even explosion. In order to ensure the operation of high-power hydrogen-related systems, it is necessary to establish a complete hydrogen safety protection system to ensure that the system has high measurement accuracy and response speed.

[0003] In the early stage of hydrogen system leakage, if the hydrogen-sensitive sensor cannot capture effective information in time, it may cause a large-scale leakage. Therefore, improving the response speed of the sensor is a key link in hydrogen safety protection. There are many types of hydrogen-sensitive sensors. As the electrolytic stack system and its safety protection system become more complex, the requirements for sensor response speed also increase.

[0004] Traditional hydrogen leak detection systems can often only detect hydrogen concentration but cannot accurately locate hydrogen leak points, which is very disadvantageous for leak detection and maintenance of high-power hydrogen-related systems. A Chinese invention patent application with publication number CN 114152650 A discloses an array hydrogen detector and its detection method, including a substrate, a TFT device layer processed and manufactured on any side of the substrate, the TFT device layer includes a plurality of detection points distributed in an array; a resistance change sensing layer is processed and manufactured on the other side of the substrate, the resistance change sensing layer is etched into a plurality of resistance change sensing modules, a through hole is opened on the substrate under each resistance change sensing module, the through hole is filled with metal, and each resistance change sensing module is electrically connected to the corresponding detection point through the metal in the through hole; a hydrogen separation film layer is processed and manufactured above the resistance change sensing layer. This invention can detect hydrogen leakage by changing the resistance value of the hydrogen sensitive device, and can also specifically calculate the concentration of the leaked hydrogen. Moreover, by setting multiple detection points to form an array-type hydrogen detection, it can locate the specific position of the hydrogen leakage and detect the source of the hydrogen leakage in time. However, the above invention realizes hydrogen leakage monitoring based on a metal resistive hydrogen sensitive sensor. Resistive sensors have the disadvantages of poor stability and selectivity, long response time and recovery time, complex sensitive mechanism, short life, and high operating temperature during use. This is also a problem that this type of sensor urgently needs to solve. Summary of the invention

[0005] The purpose of the present invention is to provide a hydrogen leakage monitoring and protection system with fast response speed and higher sensitivity, so as to at least provide a beneficial option or create conditions for solving one or more technical problems existing in the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solutions.

[0007] A flexible thin film hydrogen-sensitive sensor comprises a proton exchange membrane and a plurality of hydrogen-sensitive sensing elements arranged in an array on the proton exchange membrane, each of the hydrogen-sensitive sensing elements being composed of a counter electrode and a sensing electrode correspondingly arranged on both sides of the proton exchange membrane, and a catalytic layer being coated on the proton exchange membrane.

[0008] More preferably, the proton exchange membrane is selected from perfluorosulfonic acid proton exchange membrane, DuPont proton exchange membrane N-117, Nafion 212 membrane or Nafion 211 membrane produced by DuPont Company of the United States.

[0009] More preferably, the catalyst of the catalyst layer is platinum carbon, and the platinum carbon includes a carbon carrier and platinum particles attached to the carbon carrier.

[0010] More preferably, the counter electrode and the sensing electrode are selected from platinum electrodes and silver electrodes.

[0011] More preferably, a humidifying device and a moisturizing device are provided corresponding to the proton exchange membrane.

[0012] More preferably, the humidifying device is a water tank arranged around the proton exchange membrane and in contact with the proton exchange membrane, and the moisturizing device is a moisturizing net covering the surface of the flexible thin film hydrogen sensitive sensor.

[0013] As another aspect of the present invention, a hydrogen leakage monitoring and protection system is provided, which includes components such as a flexible thin-film hydrogen-sensitive sensor, a signal acquisition system, a programmable power supply, and a graded early warning system.

[0014] The flexible thin film hydrogen sensitive sensor is as described above.

[0015] The signal acquisition system is used to collect the electrical signal data generated by each of the hydrogen-sensitive sensor elements.

[0016] The programmable power supply is used to apply an electrical signal to each of the hydrogen-sensitive sensing elements.

[0017] More preferably, the above hydrogen leakage monitoring and protection system also includes a graded warning system, and the graded warning system is used to take different disposal measures according to different hydrogen leakage situations.

[0018] More preferably, when the hydrogen leakage monitoring and protection system is in operation, the signal acquisition system is started to monitor the electrical signals of each hydrogen-sensitive sensor element in real time; when the hydrogen-sensitive sensor element in a certain area generates an electrical signal, it means that there is hydrogen leakage in the area.

[0019] When hydrogen leaks, the time of the electrical signal data measured at each hydrogen-sensitive sensor element is different. The hydrogen leakage point is located according to the time data of the electrical signal generation, and the position of the hydrogen-sensitive sensor element that first generates the electrical signal is the hydrogen leakage position.

[0020] More preferably, after the hydrogen leakage position is determined, the hydrogen sensitive sensor element at the hydrogen leakage position is connected to a programmable power supply, and the hydrogen leakage amount is measured using a limiting current method.

[0021] More preferably, the severity of hydrogen leakage is assessed according to a pre-set risk level standard, a graded warning is issued, and different levels of subsequent treatment measures are taken.

[0022] More preferably, after the hydrogen leakage location is determined, the hydrogen sensitive sensing elements around the hydrogen leakage location are connected to a programmable power supply, and the distribution information of hydrogen in the entire detection space is determined based on the leakage location and the strength of the leakage signal.

[0023] Compared with the prior art, the present invention has the following beneficial effects.

[0024] (1) The present invention uses the principle of electrochemical reaction and is based on an electrochemical hydrogen-sensitive sensor to measure hydrogen leakage. When working, it catalyzes the hydrogen to be detected to generate an electrical signal. The electrical signal measurement response time is below the millisecond level, with high measurement accuracy, and can achieve a rapid response to hydrogen leakage at low concentrations. At the same time, this type of sensor has a wide detection range, good selectivity, high sensitivity, and no need for heating. It can respond quickly to leaks, and can quantitatively detect micro-leaked hydrogen through the working principle of electrochemistry. In addition, since there are no moving parts, there will be no mechanical failure.

[0025] (2) In the present invention, the arrangement interval of the sensor array can be set within the centimeter range as required, and the precise positioning of the hydrogen leakage position can be achieved based on the electrical signal data and response time data of each sensor.

[0026] (3) In the present invention, the number of sensor arrays can be increased according to demand to meet the needs of large-scale object hydrogen leakage monitoring.

[0027] (4) In the present invention, the flexible thin film sensor uses a flexible proton exchange membrane as the main material, which can adapt to various shapes and fit closely to the monitored object.

[0028] (5) In the present invention, the amount of hydrogen leakage can be accurately measured, and corresponding treatment measures can be taken based on the monitoring results to achieve graded treatment of hydrogen leakage; the distribution information of hydrogen in the entire detection space can be determined to provide assistance for subsequent leakage treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1This is a structural schematic diagram of the hydrogen leakage monitoring and protection system provided by the present invention.

[0030] Figure 2 Shown Figure 1 Side view of.

[0031] Figure 3 It is a schematic diagram of the principle of a single hydrogen-sensitive sensor element in the present invention.

[0032] Description of Figure Numbers.

[0033] 1: Flexible thin film hydrogen sensitive sensor, 2: Signal acquisition system, 3: Programmable power supply, 4: Graded early warning system.

[0034] 1-1: Proton exchange membrane, 1-2: Hydrogen sensitive sensor element, 1-3: Water tank.

[0035] 1-2-1: counter electrode, 1-2-2: sensing electrode. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0037] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings.

[0038] like Figure 1 , Figure 2 As shown, a hydrogen leakage monitoring and protection system includes: a flexible thin-film hydrogen-sensitive sensor 1, a signal acquisition system 2, a programmable power supply 3 and a graded early warning system 4.

[0039] Wherein, the flexible thin film hydrogen sensitive sensor 1 includes a proton exchange membrane 1-1 and a plurality of hydrogen sensitive sensing elements 1-2 arranged in an array on the proton exchange membrane 1-1, and a water tank 1-3 is arranged around the proton exchange membrane 1-1, and the water tank 1-3 is used to humidify the proton exchange membrane 1-1, and the surface of the flexible thin film hydrogen sensitive sensor 1 is covered with a dense moisturizing net to maintain the humidity of the proton exchange membrane 1-1. The size of the flexible thin film hydrogen sensitive sensor 1 and the number of hydrogen sensitive sensing elements 1-2 can be determined according to the monitored object, and the flexible thin film hydrogen sensitive sensor 1 can fit closely with the measured object. In some embodiments, the water tank 1-3 can be replaced by other humidifying devices, as long as it can humidify the proton exchange membrane 1-1; it is not limited to this embodiment.

[0040] Combination Figure 3As shown, each hydrogen-sensitive sensor element 1-2 is composed of a counter electrode 1-2-1 and a sensing electrode 1-2-2 correspondingly arranged on both sides of the proton exchange membrane 1-1, and a catalytic layer is coated on the proton exchange membrane 1-3. The counter electrode 1-2-1 and the sensing electrode 1-2-2 can be selected from platinum electrodes, silver electrodes, etc. with high conductivity, and the catalyst of the catalyst layer is preferably platinum carbon, and the platinum carbon includes a carbon carrier and platinum particles attached to the carbon carrier; of course, the catalyst can also be selected from some other catalysts that are currently known or can be realized in the future, and is not limited to this embodiment.

[0041] According to different actual needs, the proton exchange membrane 1-1 can be selected from perfluorosulfonic acid proton exchange membrane, DuPont proton exchange membrane N-117, Nafion212 membrane or Nafion211 membrane produced by DuPont (DuPont) Company of the United States.

[0042] When working, the counter electrode 1-2-1 uses air as a reference gas and reacts with oxygen in the air. The sensing electrode 1-2-2 is close to the side where the measured system is located. When there is a hydrogen leak in the measured system, the hydrogen reacts at the sensing electrode 1-2-2. The electrocatalytic reaction occurring on the hydrogen-sensitive sensing element 1-2 generates an electrical signal, and a rapid response to hydrogen leakage is achieved according to the strength of the electrical signal.

[0043] The signal acquisition system 2 is used to collect the electrical signal data and time data generated by each hydrogen-sensitive sensor element 1-2.

[0044] The programmable power supply 3 is used to apply an electrical signal to the electrodes of the hydrogen-sensitive sensor element 1-2 so as to detect the amount of hydrogen leakage using the limiting current method.

[0045] The graded warning system 4 is used to take different disposal measures according to different hydrogen leakage situations.

[0046] Example 1.

[0047] Taking monitoring hydrogen leakage in an electrolytic stack as an example, the above-mentioned flexible thin-film hydrogen-sensitive sensor 1 is arranged and attached around the electrolytic stack. The flexible thin-film hydrogen-sensitive sensor 1 can adapt well to the shape of the device under test and fit closely with the electrolytic stack. A total of m rows and n columns of hydrogen-sensitive sensor elements 1-2 arrays constitute the flexible thin-film hydrogen-sensitive sensor 1, and the distance between each sensor element 1-2 is within 1 cm (the specific value of the distance can be appropriately adjusted according to actual needs), so as to accurately locate the hydrogen leakage position.

[0048] When the above-mentioned hydrogen leakage monitoring and protection system is in operation, its working process is as follows.

[0049] The signal acquisition system 2 is started to monitor the electrical signals of each hydrogen-sensitive sensor element 1-2 in real time. When no hydrogen leakage occurs, the collected electrical signals of each hydrogen-sensitive sensor element 1-2 are zero, that is, V i,j=0, i=1,2,…,m, j=1,2,…,n; m, n are natural numbers, m, n≥3.

[0050] When an electrical signal is collected from the hydrogen sensitive sensor element 1-2 in a certain area, it means that there is a hydrogen leak in the area. For example, when the system detects the following electrical signal, V a-1,b-1 ,V a-1,b ,V a-1,b+1 ,V a,b-1 ,V a,b ,V a,b+1 ,V a+1,b-1 ,V a+1,b ,V a+1,b+1 , that is, it can be confirmed that the hydrogen leakage location is near point (a, b). According to the time data of the above signals collected, that is, T a-1,b-1 ,T a-1,b ,T a-1,b+1 ,T a,b-1 ,T a,b ,T a,b+1 ,T a+1,b-1 ,T a+1,b ,T a+1,b+1 , the hydrogen sensitive sensor element 1-2 that generates the electrical signal earliest is the hydrogen leakage position. For example, the time when point (a, b) generates the electrical signal is earlier than that of other points, that is, T a,b <T i,j , i=1,2,…,m and i≠a, j=1,2,…,n and j≠b, the hydrogen leakage position can be confirmed to be point (a, b). Since the arrangement interval of the hydrogen sensitive sensor elements 1-2 is within the centimeter range, the hydrogen leakage position can be quickly and accurately located within the centimeter range.

[0051] When the hydrogen leakage position is detected at the hydrogen sensitive sensor element 1-2 at point (a, b), the programmable power supply 3 is turned on to the hydrogen sensitive sensor element 1-2, and the hydrogen leakage amount is measured using the limiting current method. According to the pre-set risk level standard, the severity of hydrogen leakage is evaluated, and graded warnings are issued so that different levels of follow-up treatment measures can be taken.

[0052] It should be noted that the signal acquisition model selection and circuit design of the signal acquisition system 2 are common technical knowledge mastered by technical personnel in this field, and the limiting current method for detecting hydrogen leakage, as well as how to classify the leakage amount and how to set different warnings corresponding to different classifications are also common technical knowledge mastered by technical personnel in this field, and will not be elaborated here.

[0053] Obviously, the hydrogen leakage monitoring and protection system provided by the present invention can not only monitor hydrogen leakage in electrolytic stacks, but also be applied to other hydrogen storage devices or hydrogen transportation devices, as long as the flexible film hydrogen sensitive sensor 1 is attached to the corresponding device.

[0054] Through the description of the above structure and principle, those skilled in the art should understand that the present invention is not limited to the above specific implementations, and improvements and substitutions based on the present invention using the known technology in the art fall within the protection scope of the present invention, and the protection scope of the present invention should be defined by the claims and their equivalents. Parts not described in the specific implementations are prior art or common knowledge.

Claims

1. A hydrogen leakage monitoring and protection system, characterized in that: Including flexible thin film hydrogen sensitive sensor, signal acquisition system, programmable power supply and graded warning system; The flexible thin film hydrogen sensitive sensor It comprises a proton exchange membrane and a plurality of hydrogen-sensitive sensing elements arranged in an array on the proton exchange membrane, each of the hydrogen-sensitive sensing elements is composed of a counter electrode and a sensing electrode correspondingly arranged on both sides of the proton exchange membrane, and a catalytic layer is coated on the proton exchange membrane; a humidifying device and a moisturizing device are arranged corresponding to the proton exchange membrane, the humidifying device is a water tank arranged around the proton exchange membrane and in contact with the proton exchange membrane, and the moisturizing device is a moisturizing net covering the surface of the flexible thin-film hydrogen-sensitive sensor; The signal acquisition system is used to collect the electrical signal data generated by each of the hydrogen-sensitive sensor elements; The programmable power supply is used to apply an electrical signal to each of the hydrogen-sensitive sensing elements; The hierarchical warning system is used to take different disposal measures according to different hydrogen leakage situations; When the monitoring and protection system is running, the signal acquisition system is started to monitor the electrical signals of each hydrogen-sensitive sensor element in real time; when the hydrogen-sensitive sensor element in a certain area generates an electrical signal, it means that there is a hydrogen leak in the area; When hydrogen leaks, the time of the electrical signal data measured at each hydrogen-sensitive sensor element is different. The hydrogen leakage point is located according to the time data of the electrical signal generation, and the position of the hydrogen-sensitive sensor element that first generates the electrical signal is the hydrogen leakage position; After the hydrogen leakage location is determined, the hydrogen-sensitive sensor element at the hydrogen leakage location is connected to a programmable power supply, and the hydrogen leakage amount is measured using the limiting current method; based on the pre-set risk level standard and the measured hydrogen leakage amount, the severity of the hydrogen leakage is assessed, a graded warning is issued, and then different levels of subsequent treatment measures are taken.

2. A hydrogen leakage monitoring and protection system according to claim 1, characterized in that: The proton exchange membrane is selected from perfluorosulfonic acid proton exchange membrane, DuPont proton exchange membrane N-117, Nafion 212 membrane or Nafion 211 membrane produced by DuPont (DuPont) Company of the United States.

3. A hydrogen leakage monitoring and protection system according to claim 1, characterized in that: The catalyst of the catalytic layer is platinum carbon, and the platinum carbon includes a carbon carrier and platinum particles attached to the carbon carrier.

4. A hydrogen leakage monitoring and protection system according to claim 1, characterized in that: The counter electrode and the sensing electrode are selected from platinum electrodes and silver electrodes.

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