WO2022033225A1 - Hydrogen concentration measuring device resistant to high temperatures, high pressure, high humidity and high radiation, and hydrogen measuring probe - Google Patents

Abstract

A hydrogen concentration measuring device resistant to high temperatures, high pressure, high humidity and high radiation, and a hydrogen measuring probe (20). The hydrogen measuring probe (20) comprises a probe housing, a hydrogen measuring element (24) and a fixing assembly (29), wherein the probe housing is provided with a hydrogen measuring inlet covered with a filter screen (213), and the fixing assembly (29) is used for fixing the hydrogen measuring element (24) in the probe housing; and the hydrogen measuring element (24) is used for measuring the concentration of hydrogen by means of a catalytic electrochemical method and comprises a measuring element housing (241) internally provided with an insulating layer (240), a filtering permeable membrane (242), a measuring electrode (243), a counter electrode (244), a reference electrode (245), an electrolyte layer (246), an oxygen storage layer (248) and a hydrogen measuring element lead (249), the oxygen storage layer (248) being made of metal oxygen storage, oxygen release and oxygen production materials and capable of continuously releasing oxygen. In the hydrogen concentration measuring device, the hydrogen measuring probe (20) is used to measure hydrogen partial pressure. The device is applicable to hydrogen concentration measurement in high-temperature, high-pressure, high-humidity and high-radiation environments of a nuclear power plant, and is also applicable to hydrogen concentration measurement in other severe environments.

Description

Hydrogen concentration measuring device and hydrogen measuring probe resistant to high temperature, high pressure and high humidity radiation technical field

The invention belongs to the field of hydrogen concentration measurement, and more particularly, the invention relates to a hydrogen concentration measurement device and a hydrogen measurement probe that are resistant to high temperature, high pressure and high humidity radiation.

Background technique

When a serious accident occurs in a nuclear power plant, a large amount of hydrogen will be produced in the containment, and the explosion of hydrogen will threaten the integrity of the safety barrier of the nuclear power plant. The sources of a large amount of hydrogen generated in the accident condition of the nuclear power plant are as follows: in the early stage of the accident, the zirconium-water reaction produces hydrogen at a high rate; in the middle and later stages of the accident, the radiation decomposition of water, the reaction of the core melt and the concrete will also produce Plenty of hydrogen. The accumulation of a large amount of hydrogen makes it possible that the concentration of hydrogen in the containment exceeds 4% of the explosion limit, and there is a danger of explosion. In order to avoid the hydrogen deflagration accident destroying the integrity of the containment, it is necessary to build a hydrogen measurement system to monitor the hydrogen accumulation state in different positions of the containment, so as to implement effective intervention after the accident.

Under accident conditions, the gas composition in the containment is mainly composed of air and water vapor, and also contains high temperature and high pressure mixed gas of hydrogen and other gases. Under the accident condition, the reactor emits a lot of heat, the temperature in the containment increases with the pressure increase, and a large amount of radioactive substances are released into the containment building. The second-generation and second-generation plus nuclear power plants require that the hydrogen concentration measuring instrument can withstand a temperature of 150 degrees Celsius, a pressure of 6 bar, and a cumulative radiation dose of 1×10 ⁵ Gy. The irradiation dose was 6.96×10 ⁵ Gy (gamma rays) and 7.54×10 ⁵ Gy (beta rays).

Due to the characteristics of high temperature, high pressure and high radioactivity in the containment gas under accident conditions, it is very difficult to measure the hydrogen concentration. Therefore, a nuclear power plant needs a set of devices for measuring the hydrogen concentration in a serious accident, but the environmental conditions in the containment are usually harsh during a serious accident, such as high temperature, high pressure, high radiation and other harsh environments, which are not conducive to the continuous monitoring of the accident by operators, and it is difficult to Monitoring the hydrogen concentration in an effective way has extremely high requirements on the equipment in the containment.

The first existing serious accident hydrogen concentration monitoring device uses the catalytic reaction principle to indirectly measure the hydrogen concentration by measuring the reaction heat, but the device can only be used in an oxygen environment, and the heat loss, reaction parts and catalytic reaction parts are The distance affects the measurement accuracy, the hydrogen concentration measurement accuracy cannot be guaranteed, and the water droplets entering the catalytic unit under high humidity will also cause its measurement failure.

The existing second type of serious accident hydrogen concentration monitoring device is to extract the gas out of the containment for measurement, but the radioactive gas is extracted out of the containment after cooling and depressurization before measurement, and the measured parameters are difficult to accurately and truly represent the inside of the containment. Hydrogen concentration, and the extraction of radioactive gas out of the containment, there will be a rupture of the sampling line, which will further increase the leakage point of the containment, and will also increase the risk of exposure to personnel outside the containment, and the safety is not high.

The existing third serious accident hydrogen concentration monitoring device uses a hydrogen concentration sensor based on the electrochemical principle of catalytic reaction to measure the hydrogen concentration, but the hydrogen concentration sensor based on the electrochemical principle of catalytic reaction has higher semipermeable membrane and electrolyte. Due to the existence of liquid medium, it cannot withstand higher temperatures, and if the concentrated sulfuric acid leaks, it will affect the surrounding environment. In addition, the hydrogen semi-permeable membrane used will affect the response time of the hydrogen concentration sensor, resulting in a slower response speed.

The existing fourth type of serious accident hydrogen concentration monitoring device is to use a hydrogen sensor based on the principle of palladium-based alloy hydrogen absorption to measure the hydrogen concentration, but this device can only be measured under a given temperature and pressure, and the detection space is discontinuous. In addition, the hydrogen concentration probe is exposed to high temperature and humid steam environment, and the steam may short-circuit the resistance measurement circuit or fail the measurement, and the reliability of this measurement method is low.

The existing fifth serious accident hydrogen concentration monitoring device uses the electrochemical principle to measure the hydrogen concentration in a high-temperature environment, but the PEEK material and diffusion film used have weak radiation resistance, so they cannot be directly used in high-irradiation environments. , and the oxygen storage is insufficient, and the service life will be affected after the oxygen is consumed during operation.

In view of this, it is indeed necessary to provide a hydrogen concentration measuring device and a hydrogen measuring probe capable of solving the above problems and being resistant to high temperature, high pressure and high humidity radiation.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a hydrogen concentration measuring device and a hydrogen measuring probe that are resistant to high temperature, high pressure and high humidity radiation, so as to ensure that it can be realized in the presence of oxygen, no oxygen, high temperature, high pressure, high humidity, radiation and high hydrogen concentration. Accurate measurement of hydrogen concentration.

In order to achieve the above purpose of the invention, the present invention provides a hydrogen measuring probe resistant to high temperature, high pressure and high humidity radiation, which includes a probe casing, a hydrogen measuring element and a fixing assembly. For fixing the hydrogen measuring element in the probe housing;

The hydrogen measuring element adopts a catalytic electrochemical method to measure the hydrogen concentration, and includes a measuring element casing with an insulating layer, a filter permeable membrane, a measuring electrode, a counter electrode, a reference electrode, an electrolyte layer, an oxygen storage layer and a hydrogen measuring element lead wire, Among them, the filter permeable membrane is fixed on one end of the measuring element shell, the oxygen storage layer is fixed on the other end of the measuring element shell, the measuring electrode, the counter electrode and the reference electrode are all arranged inside the measuring element shell; the measuring electrode is set close to the filter permeable membrane, The counter electrode and the reference electrode are set together on the side of the measuring electrode facing away from the filter permeable membrane, and the electrolyte layer is set between the measuring electrode, the counter electrode and the reference electrode, and between the layer where the counter electrode and the reference electrode are located and the oxygen storage layer. The space is the oxygen storage space; the hydrogen measuring element has at least three leads, which are respectively connected with the measuring electrode, the counter electrode and the reference electrode;

The oxygen storage layer adopts metal oxygen storage and oxygen releasing and producing materials, which can continuously release oxygen.

As an improvement of the high temperature, high pressure and high humidity radiation-resistant hydrogen measuring probe of the present invention, the oxygen storage layer includes an oxygen release material, an oxygen storage material and a catalytic material, the oxygen release material is calcium peroxide CaO ₂ , and the oxygen storage material is CeO _2-x or YBa(Co _1-x Al _x ) ₄ O _7+δ or YBaCo ₄ O _7+δ , the catalytic material selects rhodium, ruthenium, palladium, gold, iridium, silver, platinum or an alloy of the aforementioned metals; the The oxygen storage layer also includes a water-absorbing material or a water-absorbing layer is arranged on the side of the oxygen storage layer facing the inside of the housing of the measuring element. The water-absorbing material or the water-absorbing layer is used to absorb the moisture in the probe, ensure that the air is relatively dry, and lock the moisture for oxygen storage. layer usage.

As an improvement of the hydrogen measuring probe with high temperature, high pressure and high humidity radiation resistance of the present invention, the casing of the measuring element is made of stainless steel with strong mechanical strength and radiation resistance. Material.

As an improvement of the hydrogen measuring probe resistant to high temperature, high pressure and high humidity radiation of the present invention, the filtration permeable membrane is a semi-permeable membrane with a double-layer structure, including an outer selective permeable membrane and an inner selective permeable membrane. The selective permeation membrane is a PET selective permeation membrane or a dense ceramic membrane, and the inner selective permeation membrane is a palladium alloy membrane or a niobium alloy membrane.

As an improvement of the hydrogen measuring probe resistant to high temperature, high pressure and high humidity radiation of the present invention, the measuring electrode and the counter electrode are metal porous carbon electrode plates, including an electrode support layer and a catalyst layer, and the support material of the electrode support layer is ETFE; the electrode catalyst of the measurement electrode catalyst layer is platinum or platinum alloy, and the electrode catalyst of the counter electrode catalyst layer is one or a mixture of rhodium, ruthenium, palladium, gold, iridium, silver, platinum, or a mixture with other metals The reference electrode plays the role of a stable potential zero point, and the same metal porous electrode plate as the measuring electrode is selected.

As an improvement of the high temperature, high pressure and high humidity radiation-resistant hydrogen measuring probe of the present invention, the electrode catalyst of the counter electrode catalyst layer is selected from platinum alloys, preferably platinum-chromium alloys, platinum-titanium alloys, platinum-iron-manganese ternary alloys or platinum-iron alloys Cobalt ternary alloy.

As an improvement of the hydrogen measuring probe resistant to high temperature, high pressure and high humidity radiation of the present invention, the counter electrode further comprises a solid oxidant layer, and the oxidant of the solid oxidant layer adopts CeO _2-x or YBa(Co _1-x Al _x ) ₄ O _7+δ or YBaCo ₄ O _7+δ or ceria-zirconia.

As an improvement of the hydrogen measuring probe with high temperature, high pressure and high humidity radiation resistance of the present invention, the electrolyte layer adopts 95% to 99% concentrated phosphoric acid as a liquid substance, and an electrolyte holding material is provided for adsorbing concentrated phosphoric acid, and the electrolyte layer is Retention materials include silicon carbide and ETFE.

As an improvement of the hydrogen measuring probe resistant to high temperature, high pressure and high humidity radiation of the present invention, the hydrogen measuring probe further includes a heating assembly, and the heating assembly includes a heating support layer, a temperature probe, a temperature probe lead, a heating element and a heating element lead; heating The support layer is the structural support part of the heating assembly, the temperature probe is closely fixed on the heating support layer, and the heating element is a metal heating sheet or a ceramic heater fixed on the heating support layer.

As an improvement of the hydrogen measuring probe with high temperature, high pressure and high humidity radiation resistance of the present invention, the hydrogen measuring probe also includes a cable gland and an anti-spray assembly. The connector ensures that the inner space of the probe shell is sealed, and at the same time ensures that the lead wire in the probe shell and the cable outside the probe shell are quickly connected; the probe shell includes the probe upper shell and the probe lower shell which are sealed and connected, and the anti-spray component is fixed on the probe upper shell. In order to prevent the upper spray water from being directly sprayed to the hydrogen measurement inlet located in the lower casing of the probe.

In order to achieve the above purpose of the invention, the present invention also provides a hydrogen concentration measuring device that is resistant to high temperature, high pressure and high humidity radiation, which includes a pressure sensor for measuring the pressure at the position to be measured, a hydrogen measuring probe for measuring the partial pressure of hydrogen at the position to be measured, and signal processing. and a control device, the hydrogen measuring probe is the hydrogen concentration measuring probe that is resistant to high temperature, high pressure and high humidity radiation as described in any of the above paragraphs; the signal processing and control device are respectively connected with the pressure sensor and the hydrogen measuring probe through cables for collecting Pressure sensor and hydrogen measurement probe signals are processed and converted to hydrogen concentration.

As an improvement of the hydrogen concentration measuring device of the present invention that is resistant to high temperature, high pressure and high humidity radiation, the hydrogen measuring probe signal includes a hydrogen concentration signal and a temperature signal; the signal processing and control device is located in the electronic equipment room, including signal input and output components , processing components and signal remote transmission components; the signal input and output components are connected to the pressure sensor and the hydrogen measurement probe through a cable that is resistant to high temperature and radiation, and is used to collect the pressure signal of the pressure sensor, the hydrogen concentration signal and temperature of the hydrogen measurement probe. Signal; the processing part is connected with the signal input and output part, used to calculate the hydrogen proportional concentration in the measured gas according to the hydrogen concentration signal and the pressure signal, and the signal remote transmission part is used to output the hydrogen proportional concentration to the external user.

As an improvement of the high temperature, high pressure and high humidity radiation-resistant hydrogen concentration measuring device of the present invention, the processing component is also used for converting the temperature signal into a heating control signal for controlling the heating element, and the signal input and output component is also used for receiving the heating control signal , and convert it into the voltage and current signal of the heating element and output it to the heating element.

Compared with the prior art, the hydrogen concentration measuring device and the hydrogen measuring probe which are resistant to high temperature, high pressure and high humidity radiation of the present invention are suitable for the hydrogen concentration measurement in the high temperature, high pressure, high humidity and high radiation environment of nuclear power plants, and are also suitable for other harsh environments. under the hydrogen concentration measurement.

Description of drawings

The following describes the hydrogen concentration measuring device and the hydrogen measuring probe which are resistant to high temperature, high pressure and high humidity radiation according to the present invention with reference to the accompanying drawings and specific embodiments.

FIG. 1 is a schematic diagram of the overall structure of the hydrogen concentration measuring device resistant to high temperature, high pressure and high humidity radiation according to the present invention.

FIG. 2 is a schematic structural diagram of the hydrogen measuring probe resistant to high temperature, high pressure and high humidity radiation according to the present invention.

FIG. 3 is a schematic structural diagram of the hydrogen measuring element of the hydrogen measuring probe in FIG. 2 .

FIG. 4 is a schematic diagram of the principle of the hydrogen measuring element in FIG. 3 .

FIG. 5 is a preferred structure of the filtration permeable membrane in FIG. 3 .

FIG. 6 is a schematic structural diagram of the signal processing and control device in FIG. 1 .

FIG. 7 is a schematic diagram of the pressure signal acquisition circuit in FIG. 6 .

FIG. 8 is a schematic diagram of the temperature acquisition circuit in FIG. 6 .

FIG. 9 is a schematic diagram of the heating element control output module in FIG. 6 .

FIG. 10 is a schematic diagram of an embodiment of the counter electrode of the hydrogen measuring element in FIG. 3 .

detailed description

In order to make the objectives, technical solutions and beneficial technical effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described in this specification are only for explaining the present invention, rather than for limiting the present invention.

Please refer to FIG. 1 , the hydrogen concentration measuring device of the present invention that is resistant to high temperature, high pressure and high humidity radiation includes:

a pressure sensor 10 for measuring the pressure at the position to be measured;

a hydrogen measuring probe 20 for measuring the partial pressure of hydrogen at the position to be measured;

The signal processing and control device 40 is connected to the pressure sensor 10 and the hydrogen measuring probe 20 through the cable 30. The signal processing and control device 40 is used to collect the signals of the pressure sensor 10 and the hydrogen measuring probe 20 and process them, and convert them into hydrogen concentration . The signal processing and control means 40 are located in the electronics room.

The location to be measured can be a harsh environment with high temperature, high pressure, high humidity, and irradiation, such as a nuclear power plant or other harsh environments, and can be applied to a temperature of 170 degrees Celsius, a pressure of 6.5 bar, and a cumulative radiation dose of 6.96×10 ⁵ Gy (γ ray), 7.54×10 ⁵ Gy (β ray), 100% high temperature steam environment. It is easy to understand that the location to be tested can also be a relatively mild environment where any one or several of the temperature, pressure, humidity, and irradiation are lower than the containment.

The hydrogen measuring probe 20 is the core component of the hydrogen concentration measuring device of the present invention, and undertakes the hydrogen partial pressure measuring function, which will be described in detail below.

Referring to FIG. 2 , the hydrogen concentration measuring probe 20 resistant to high temperature, high pressure and high humidity radiation of the present invention includes a probe housing, a cable gland 22 , a spray prevention component 23 , a hydrogen measuring element 24 , a heating component and a fixing component 29 .

The probe housing includes an upper probe housing 210 and a lower probe housing 212. The probe upper housing 210 and the probe lower housing 212 are made of 304L or 316L stainless steel or other stainless steel with high temperature resistance, radiation resistance and corrosion resistance. The front end of the probe lower casing 210 is provided with a hydrogen measurement inlet, and the hydrogen measurement inlet is covered with a sintered stainless steel filter 213 to ensure its air permeability and mechanical strength, and at the same time, it can prevent large particles such as aerosols from entering the probe casing, except for the hydrogen measurement inlet. , the other parts of the probe shell are sealed structures. The upper casing 210 of the probe and the lower casing 212 of the probe are connected by screw sealing. In order to ensure that the space inside the casing is sealed, a high temperature and radiation resistant sealant can also be used to seal the joint between the two to ensure the inner space of the probe casing and the outside. Space isolation, preventing external hydrogen from entering the inner space of the probe shell from the joint of the upper and lower shells, and avoiding the leakage of internal gas.

The cable gland 22 is installed in the probe shell, and adopts high temperature and radiation-resistant quick connectors to ensure that the inner space of the probe shell is sealed, and at the same time, it can ensure the quick connection between the lead wire in the probe shell and the cable 30, which can not only reduce the replacement of the hydrogen measuring probe 20 and the connection time, and can effectively ensure that the inner space of the probe shell is sealed.

The anti-spray assembly 23 is fixed on the upper casing 210 of the probe to prevent the upper spray water from being directly sprayed to the hydrogen measurement inlet of the lower casing 212 of the probe. The anti-spray assembly 23 can be made of the same material as the housing 210 on the probe.

Please refer to Fig. 3 and Fig. 4, the measurement principle of the hydrogen measuring element 24 is:

A filter permeable membrane 242 is installed on the contact surface of the hydrogen measuring element 24 and the external measured gas. The filter permeable membrane 242 allows hydrogen to pass through, while avoiding the intrusion of gases such as water vapor, O ₂ and CO, and finally ensures that the concentration of hydrogen molecules is between the inside and outside of the filter permeable membrane. side to achieve dynamic balance.

Both the measurement electrode 243 and the counter electrode 244 contain catalysts, and the measurement electrode 243 contacts the hydrogen gas of the measurement gas to catalyze the oxidation reaction of the hydrogen gas to generate electrons and generate hydrogen ions. H ⁺ is transferred from the measurement electrode 243 to the counter electrode 244 in the electrolyte layer 246 , and there is an oxide layer on the side of the counter electrode 244 , and a reduction reaction proceeds.

Measuring electrode: H ₂ →2H ⁺ +2e ^- ;

Counter electrode: 1/2O ₂ +2H ⁺ +2e ^- →H ₂ O.

The electrons are transmitted in the external circuit, and the hydrogen molecule concentration of the measured gas is measured by measuring the potential of the external measuring element. If the content of hydrogen molecules in the measured gas is low, the potential is low; if the content of hydrogen molecules in the measured medium is high, the potential is high.

In order for the reaction to occur, the potential of the measurement electrode 243 must be kept within a specific range. However, as the concentration of the gas increases, the reaction current also increases, thus causing a potential change (polarization) of the counter electrode 244. Since the measuring electrode 243 and the counter electrode 244 are connected through a simple load resistance, although the potential of the measuring electrode 243 will also change with the potential of the counter electrode 244, if the concentration of the gas increases continuously, the measuring electrode 243 The potential of the gas may eventually move out of its allowable range, and the sensor will not be linear at this point, so the upper limit concentration detected by the two-electrode gas sensor is limited. To this end, a potentiostatic operating circuit and a reference electrode 245 are designed. In this way, the measurement electrode curve maintains a fixed value relative to the reference electrode 245, and no current flows in the reference electrode 245, so the measurement electrode 243 and the counter electrode 244 are both maintained at a constant potential; the counter electrode 244 can still be polarized, The measuring range is finally increased.

The hydrogen measuring element 24 designed according to the above principle includes a measuring element casing 241 with an insulating layer 240, a filter permeable membrane 242, a measuring electrode 243, a counter electrode 244, a reference electrode 245, an electrolyte layer 246, an oxygen storage layer 248, and a hydrogen measurement Component leads 249. Among them, the filter permeable membrane 242 is fixed on one end of the measuring element casing 241, the oxygen storage layer 248 is fixed on the other end of the measuring element casing 241, and the measuring electrode 243, the counter electrode 244, and the reference electrode 245 are all arranged inside the measuring element casing 241. The measuring electrode 243 is arranged close to the filtration permeable membrane 242, the counter electrode 244 and the reference electrode 245 are jointly arranged on the side of the measuring electrode 243 facing away from the filtration permeable membrane 242, and the electrolyte layer 246 is sealed between the measuring electrode 243, the counter electrode 244 and the reference electrode between 245. The space between the layers where the counter electrode 244 and the reference electrode 245 are located and the oxygen storage layer 248 is an oxygen storage space. There are at least three leads 249 of the hydrogen gas measuring element, which are respectively connected to the measuring electrode 243 , the counter electrode 244 and the reference electrode 245 .

The housing 241 of the measuring element is made of materials with strong mechanical strength and radiation resistance, such as 304L or 316L stainless steel or other stainless steel with high temperature resistance, radiation resistance and corrosion resistance. The measuring element casing 241 is provided with an insulating layer 240 which prevents the measuring electrode 243 from conducting with the counter electrode 244, and can be made of PEEK (polyetheretherketone) material or ETFE (ethylene-tetrafluoroethylene copolymer) material. The insulating layer 240 needs to be insulated from the measuring element housing 241 to prevent the conduction of the counter electrode 244 and the measuring electrode 243, and at the same time ensure a certain density and reduce the permeability of the gas from the insulating layer 240. The insulating layer 240 can be separated from other components and edges. Sealing is achieved by penetrating the fluorine sealant.

The filter permeable membrane 242 is fixed on one end of the measuring element housing 241, and ensures the sealing of the edge. The edge can be sealed with a heat-resistant and radiation-resistant sealant, such as fluorine sealant. The function of the filter permeable membrane 242 is to effectively ensure the penetration of hydrogen gas and prevent macromolecular substances such as water vapor from entering the housing 241 of the measuring element. The filtration permeable membrane 242 adopts a semi-permeable membrane, and the semi-permeable membrane must be selected for high temperature resistance, certain pressure resistance, corrosion resistance and radiation resistance.

Specifically, PET (Polyethylene terephthalate, polyester resin) selective permeation membrane can be selected as the filter permeation membrane, which has a smaller molecular sieve to ensure the selective passage of small molecular gases such as hydrogen, and the price is cheap. Some macromolecular gases may also be accompanied by permeation. Or use palladium or palladium metal hydrogen selective filter membrane, palladium alloy membrane can choose palladium iridium, palladium iridium ruthenium, palladium silver, palladium copper, palladium chromium, palladium nickel alloy, etc., pure metal palladium membrane has high hydrogen selectivity, It can pass 100%, but the stability is poor, and phase transition will occur in hydrogen atmosphere. Adding other elements can improve the performance and inhibit the phase transition stability, but some metal films are affected by gases such as CO, which ultimately affect the permeability; or choose niobium (Nb) ) alloy films, pure metals and single-phase alloys cannot take into account high hydrogen permeability and resistance to hydrogen embrittlement. For example, Nb-Ti-Ni ternary alloys with high hydrogen permeability and resistance to hydrogen embrittlement are selected.

To overcome the above situation, the filter permeable membrane 242 may employ two layers of selective materials, as shown in FIG. 5 . According to the possible molecular conditions and diameters of the measured gas, H ₂ (0.289nm), NO (0.317nm) have similar molecular diameters, CO ₂ (0.33nm), O ₂ (0.346nm), N ₂ (0.364nm), CO ( 0.376nm), CH ₄ (0.38nm), C ₂ H ₄ (0.39nm) are directly larger, and the type-selective permeable membrane can adopt a double-layer structure: the outer layer of selective permeable membrane can choose PET selective permeable membrane Or dense ceramic membrane, mainly used to filter out molecules of 0.32nm and above, the focus is to filter out H ₂ O, CO, N ₂ and O ₂ ; the inner layer selective permeable membrane selects hydrogen such as palladium alloy membrane or niobium alloy membrane The adsorbent material is prepared on the ceramic selective permeable membrane. This design can enhance the effect of filtering gas and solve the problem of metal membrane poisoning. The gas that finally penetrates into the sensor is only H ₂ molecules.

The measuring electrode 243 and the counter electrode 244 of the hydrogen measuring element 24 are porous carbon electrode plates using metal catalysts. The electrode plates have the characteristics of porosity, low density, high mechanical strength, good corrosion resistance and low resistance, including the electrode support layer. and catalyst layer. The measuring electrode 243 is mainly used for catalytic reaction, and the electrode catalyst can be platinum or platinum alloy. The measuring electrode 243 is in direct contact with the hydrogen environment and must effectively prevent the platinum alloy from being poisoned by gases such as carbon monoxide and reduce its performance. Therefore, on the one hand, before the measuring electrode 243 Covering the filter permeable membrane 242 to filter out other gases can also make the hydrogen measuring probe 20 suitable for high humidity and water vapor environments. On the other hand, platinum alloys can be used to improve the ability of the electrode to be poisoned by gas components, such as platinum tantalum Binary alloys, etc. The counter electrode 244 is a hydrogen reduction reaction layer, and the electrode catalyst can be one or a mixture of several metals among rhodium, ruthenium, palladium, gold, iridium, silver, and platinum, or alloys with other metals, such as platinum alloys. The counter electrode 244 can be made of platinum alloy. Platinum alloy can effectively improve electrode performance, ensure higher activity and better stability. Platinum-chromium alloy (Pt-Cr), platinum-titanium alloy (Pt-Ti), platinum alloy can also be used. Iron-manganese ternary alloy (PT-Fe-Mn), platinum-iron-cobalt ternary alloy (Pt-Fe-Co), etc.

The thinner catalyst layers of the measuring electrode 243 and the counter electrode 244 are conducive to better gas diffusion and catalyst utilization, while thicker layers can contain more catalyst loading and provide more three-phase regions. The optimization needs to take into account both the mass transport and the catalytic activity. The thickness of the catalyst layer of the measuring electrode 243 and the counter electrode 244 of the present invention is 10-50 μm.

The catalyst layers of the measuring electrode 243 and the counter electrode 244 are reinforced by a thick porous electrode support layer, which is called a gas diffusion layer (carbon paper can be used). The gas diffusion layer can protect the fine catalyst structure, provide a certain mechanical strength, allow the gas to reach the catalyst freely, and improve the electrical conductivity. The thickness of the electrode support layer is usually 100 to 400 μm. Similar to catalyst layers, thinner electrode support layers generally provide better gas transport, but at the same time may result in increased electrical resistance or decreased mechanical strength. The electrode support layer material also needs to consider the radiation resistance characteristics. Ordinary PTFE (polytetrafluoroethylene), PFA (soluble polytetrafluoroethylene) and other materials have poor radiation resistance, and chain scission will occur under high-energy irradiation, PTFE It decomposes rapidly under high-dose radiation, so ETFE (ethylene-tetrafluoroethylene copolymer) or the like can be used as the support material.

The measuring electrode 243 and the counter electrode 244 can be formed by spraying, filtering or rolling method. As an example of its structure and processing form and process, the measuring electrode 243 and the counter electrode 244 adopt a three-layer structure:

The first layer, the electrode support layer. After using carbon paper to infiltrate 30%-50% ETFE emulsion, the porosity is reduced to about 60%, and the average pore size is 12.5 μm. The thickness of the electrode support layer is 0.2-0.4 mm, which plays the role of supporting the catalytic layer and simultaneously collecting and conducting current.

The second layer, the diffusion layer. In order to facilitate the preparation of the catalytic layer on the support layer, a diffusion layer with a thickness of about 1-2 μm is prepared on the surface of the carbon paper, which is mixed with X-72 carbon and 50% ETFE emulsion, and the preparation process can be sprayed.

The third layer is the catalyst layer. The diffusion layer is covered with a catalyst layer composed of the metal catalyst of the corresponding electrode + ETFE emulsion (30% to 50%), with a thickness of about 50 μm, and the preparation process can be sprayed.

The reference electrode 245 plays the role of stabilizing the potential zero point, and the same metal porous electrode plate as the measuring electrode 243 can be selected, or a metal porous electrode different from the measuring electrode 243 can be selected. The structure of the reference electrode 245 can be designed as a porous electrode structure similar to that of the measurement electrode 243, and the supporting material can be ETFE (ethylene-tetrafluoroethylene copolymer) or the like.

The electrolyte layer 246 uses concentrated phosphoric acid as a liquid substance, and is provided with an electrolyte holding material for adsorbing the concentrated phosphoric acid. Concentrated phosphoric acid selects 95% to 99% concentrated phosphoric acid. The electrolyte of the invention adopts concentrated phosphoric acid solution. Phosphoric acid has low conductivity at normal temperature, good ionic conductivity at high temperature, and the working temperature is about 200°C. Phosphoric acid is a colorless, oily and water-absorbing liquid that can isolate conductive hydrogen ions in solution. The freezing point of concentrated phosphoric acid (100% by mass) is 42°C, below which the electrolyte will solidify. When the hydrogen measuring element 24 is in operation, its temperature is maintained at about 200°C by the heating element 28 and the temperature control part. The electrolyte holding material for adsorbing concentrated phosphoric acid requires low electronic conductivity, good thermal conductivity and acid resistance, and the electrolyte holding material includes silicon carbide and ETFE, preferably made of silicon carbide and ETFE.

Since the reaction on the counter electrode 244 requires oxygen to participate, there is not enough space to store oxygen in the sealed hydrogen measuring element 24. Therefore, in order to prolong the life of the hydrogen measuring probe 20, in addition to ensuring that there is a certain oxygen storage space in the hydrogen measuring element 24, The oxygen storage layer 248 also needs to be designed. The oxygen storage layer 248 uses a metal material for oxygen storage and production of oxygen, which can continuously release oxygen and has the ability to adjust the gas in the hydrogen measuring element 24 to a certain extent. The oxygen storage layer 248 needs to have the ability to store oxygen at a working temperature of the sensor around 200°C.

The oxygen storage layer 248 of the present invention includes a certain oxygen release material, an oxygen storage material and a small amount of catalytic material. The oxygen-releasing material can be selected from calcium peroxide CaO ₂ . Calcium peroxide itself is a white or light yellow crystalline powder, insoluble in water, but soluble in acid. According to the characteristics of calcium peroxide CaO ₂ , absorbing water will slowly release oxygen. Under the operating environment of the hydrogen measuring element 24 , absorbing water will release oxygen, which can provide oxygen to the counter electrode 244 . The oxygen storage material can be selected from CeO _2-x or YBa(Co _1-x Al _x ) ₄ O _7+δ or YBaCo ₄ O _7+δ , etc. In an oxygen-poor environment, the oxygen storage material releases lattice oxygen to ensure The oxygen reacted by the electrode reacts with H ₂ to generate H ₂ O; under oxygen-rich conditions, the oxygen storage material can absorb and store oxygen, and can also react with CO, NO, H ₂ and other gases to improve the internal space of the hydrogen measuring element 24. gas. The catalytic material is used to consume the combustible gas inside the probe, such as a small amount of H ₂ , CO and other gases, and together with the oxygen storage material, improve the gas in the hydrogen measuring element 24 . The catalytic material can be selected from rare metals such as rhodium, ruthenium, palladium, gold, iridium, silver, platinum, and alloys of the metals. The oxygen storage layer 248 also includes a water-absorbing material or a water-absorbing layer 247 is provided on the side of the oxygen-storage layer 248 facing the inside of the measuring element housing 241 (as shown in FIG. 3 and FIG. 4 ). The water-absorbing material or the water-absorbing layer 247 is mainly used for absorbing hydrogen. The moisture in the measuring element 24 ensures that the air is relatively dry and locks the moisture for the oxygen storage layer 248; the water absorbing material or the water absorbing layer 247 can be selected from high temperature resistant cotton or high temperature resistant water absorbent resin.

The hydrogen measurement lead 249 adopts a high temperature and radiation resistant insulated cable. For example, the material of the cable core wire can be selected from good conductor materials such as Au, Pt, and Cu, and the insulating material of the sheath can be selected from ETFE.

Please continue to refer to Figure 2. The heating component of the hydrogen measuring probe 20 is mainly used to maintain the working temperature of the probe. When the probe is running, ensure that the probe temperature is kept at about 200 °C, so that the concentrated phosphoric acid can be kept in the liquid state for a long time, without crystallization, and maintain electrical conductivity. It can also ensure that the hydrogen measuring element 24 measures at a constant temperature, obtains a hydrogen reaction curve at a constant temperature, and reduces the influence of external high temperature changes on the measurement. In the embodiment shown in FIG. 2 , the heating assembly is installed on the upper part of the hydrogen measuring element 24 with a certain gap. In different embodiments, the heating assembly can also be installed in the gap between the hydrogen measuring element 24 and the probe housing to improve the temperature control effect.

The heating assembly includes a heating support layer 26 , a temperature probe 27 , a temperature probe lead 270 , a heating element 28 and a heating element lead 280 .

The heating support layer 26 is a structural support component of the heating assembly, which can be supported by a mesh-like metal plate structure, so as to ensure a certain mechanical strength and thickness, and is not easily deformed. The material of the heating support layer 26 can be selected from 304L or 316L stainless steel or other stainless steel with the characteristics of high temperature resistance, radiation resistance and corrosion resistance.

The temperature probe 27 is closely fixed on the lower part of the heating support layer 26. The temperature probe 27 can use temperature measuring elements such as thermal resistance and thermocouple.

The heating element 28 is the core of the heating assembly, and it is necessary to consider not only the characteristics of high temperature resistance and radiation resistance, but also better heating performance, and a metal heating sheet or a ceramic heater can be selected. The metal heating plate is a device that fixes the resistance heating wire on the mica plate (mica plate). The heating material can be selected from constantan, nickel-chromium alloy (Cr20Ni80), nickel-chromium alloy (Cr30Ni70) and other materials. The ceramic heater is made of high-efficiency heater with uniform heat distribution and metal alloy with good thermal conductivity. PTC ceramic heating element or MCH ceramic heating element can be selected (alumina ceramics and built-in heating wire are used as heating element). PTC ceramic heating element is composed of PTC ceramic heating element and aluminum tube. PTC ceramic is mainly composed of barium titanate (or strontium, lead), adding a small amount of rare earth (Y, Nb, Bi, Sb), acceptor (Mn, Fe) ) elements and additives such as glass (silicon oxide, alumina), which are sintered into semiconductor ceramics. The ceramic heater will not produce "redness" on the surface and is relatively safe, so the heating element 28 is preferably a ceramic heater, and the ceramic heater can be fixed on the heating support layer 26 by a metal piece. The heating element lead 280 adopts a cable that is resistant to high temperature and radiation.

The fixing assembly 29 is used for fixing the hydrogen measuring element 24 in the probe housing, and provides a position where the heating support layer 26 can be fixedly installed, and at the same time, it is convenient for the cable leads to be led out to the cable gland 22 from both sides. The fixing component 29 can be made of metal materials, such as 304L or 306L stainless steel, etc. The mechanical structure of the fixing component can be structurally designed in combination with specific products.

Please refer to FIG. 1 and FIG. 6 , the parts other than the hydrogen measuring probe 20 in the hydrogen concentration measuring device with high temperature, high pressure and high humidity radiation resistance of the present invention will be described below.

The pressure sensor 10 can be a pressure sensor that is resistant to high temperature, high pressure, and high radiation, for example, a mechanical pressure sensor that is resistant to high temperature and high radiation. The signal of the pressure sensor 10 is mainly a measurement signal of 4 to 20 mA, which is sent to the pressure signal acquisition circuit 420. The pressure signal acquisition circuit 420 needs to be sent to the analog intrinsic safety barrier first, and then sent to the two-wire analog acquisition card to collect the pressure. The electrical signal of the sensor is converted into a digital signal and sent to the hydrogen concentration conversion module 442 .

The signal processing and control device 40 is mainly used to realize the collection of the pressure signal of the pressure sensor, the collection of the hydrogen concentration signal, the conversion and output of the hydrogen concentration signal, the collection of the temperature signal, and the heating control of the heating element. The signal processing and control device 40 includes a signal input and output part 42 , a processing part 44 and a signal remote transmission part 46 . The signal input and output component 42 is connected to the pressure sensor 10 and the hydrogen measuring probe 20 through the cable 30 that is resistant to high temperature and radiation, and is used to collect the signals of the pressure sensor 10 and the hydrogen measuring probe 20; the processing component 44 is connected to the signal input and output component 42, using It is used to process the pressure signal and realize temperature control; the signal remote transmission part 46 is connected with the processing part 44 to realize the remote transmission of the hydrogen signal.

The cable 30 is used to transmit the signal of the hydrogen measuring element 24 , the signal of the temperature probe 27 , the measurement and control signals of the heating element 28 . The cable 30 under high temperature, high pressure, high humidity, and irradiation environment needs to choose a cable that can withstand the environmental conditions. For example, the cable core wire can be made of good conductor materials such as pure copper, and the braided shielding, sheath insulating material and outer protective material can be used. The cover material can choose ETFE cable. The cable 30 can also be a cable with a mineral insulating layer and a metal alloy jacket, but the jacket of this type of cable is hard and difficult to lay. The cable section between the electronic equipment does not need to be resistant to high temperature, high pressure and radiation, which can appropriately reduce the requirements of the cable under this working condition.

The signal input and output component 42 is connected to the pressure sensor 10 and the hydrogen measuring probe 20 through the high temperature and radiation resistant cable 30, and is used to collect the pressure signal of the pressure sensor 10, the hydrogen concentration signal and the temperature signal of the hydrogen measuring probe 20, and is also used for The heating control signal is received and converted into voltage and current signals of the heating element 28 and output to the heating element 28 . The signal input and output component 42 includes a pressure signal acquisition circuit 420 , a hydrogen concentration signal acquisition circuit 422 , a temperature acquisition circuit 424 , and a heating element control output module 426 .

Please refer to Figure 7, the pressure signal acquisition circuit 420 is matched with the pressure sensor 10. The acquisition circuit uses a 2-wire 4-20mA analog signal to input to the intrinsic safety barrier, and then sends it to the input card (two-wire analog acquisition card), The electrical signal of the pressure sensor 10 is converted into a digital signal P, and _the pressure signal is sent to the hydrogen concentration conversion module 442 after being processed.

The hydrogen concentration signal acquisition circuit 422 adopts a constant potential design circuit. According to the circuit design, a three-electrode circuit design can be used. By detecting the current of the potentiostatic circuit, the concentration of hydrogen gas is given according to the relationship between hydrogen gas and current. The three-electrode circuit can effectively solve the problem of unstable reference potential caused by the consumption of the counter electrode. The three-electrode circuit design belongs to the general circuit of electrochemical sensors, and will not be repeated here. According to Faraday's first law, the current I between the measuring electrode 243 and the counter electrode 244 and the molar amount N _H2 of _H2 that diffuses to the surface of the electrode and reacts conform to the following formula: N _H2 =I/2F, where F is Faraday Constant (96500C/mol).

Please refer to FIG. 8, the temperature acquisition circuit 424 is selected in combination with the temperature probe 27, and the thermal resistance and thermocouple acquisition circuits can be selected. The temperature probe 27 is sent to the temperature acquisition safety barrier, and then input to the input card. For example, if the thermal resistance temperature probe of PT100 is selected, a 4-wire acquisition circuit is used, the temperature signal is sent to the 4-wire temperature acquisition safety barrier, and the temperature signal (4-20mA) processed by the safety barrier is sent to the input card for the temperature The signal is converted into a digital signal, and the temperature signal is sent to the temperature control loop 444 after being processed.

Referring to FIG. 9 , the heating element control output module 426 mainly receives the heating control signal of the temperature control loop 444 , converts it into pressure and current signals of the heating element 28 , and outputs it to the heating element 28 through the output safety barrier circuit.

The processing unit 44 is connected to the signal input and output unit 42 for calculating the hydrogen proportional concentration in the measured gas according to the hydrogen concentration signal and the pressure signal, and for converting the temperature signal into a heating control signal for controlling the heating element 28 . The processing component 44 includes a hydrogen concentration conversion module 442 and a temperature control loop 444 .

The hydrogen concentration conversion module 442 collects the current signal I of the hydrogen concentration signal and the pressure signal P _of the measured gas, and the main equation is as follows: XH _2,0 =K _H2 IRTδ/2FADP _full ; wherein, X _H2,0 is the measured The mole fraction of _H2 in the gas, K _H2 is the conversion constant, I is the measurement current, R is the universal gas constant, T is the operating temperature of the sensor, δ is the thickness of the diffusion layer, F is the Faraday constant (96500C/mol), A In order to measure the electrode area, D is the effective diffusion coefficient of the mixed gas of H2 and air in the diffusion layer, and P is the pressure of the mixed gas. In different implementations, XH2,0 can also be converted into values of other units for users to use in combination with the needs of use.

The temperature control loop 444 receives the temperature signal from the temperature acquisition circuit 424 and converts it into a heating control signal for controlling the heating element. The temperature control loop 444 can use a PID control algorithm, and the deviation value of the temperature signal compared with the target temperature value (200°C) is used as the input of the PID control loop, and is calculated by the PID control algorithm to finally generate the heating control signal of the heating element 28.

The signal remote transmission component 46 includes a hydrogen signal output module 460, and the hydrogen signal output module 460 outputs the hydrogen proportional concentration XH _2,0 converted from the hydrogen concentration to the external user.

From the above description, it can be seen that the hydrogen concentration measuring device of the present invention that is resistant to high temperature, high pressure, and high humidity radiation is designed in a high temperature, high pressure, high humidity, and irradiation environment. The pressure sensor 10 and the hydrogen measuring probe 20 are designed. The signal is sent to the signal processing and control device 40 in the electronic equipment room through the high temperature and radiation resistant cable 30 for processing, which is suitable for the hydrogen concentration measurement in the high temperature, high pressure, high humidity and high radiation environment of the nuclear power plant, and also suitable for other harsh environments. under the hydrogen concentration measurement.

Compared with the prior art, the hydrogen concentration measuring device resistant to high temperature, high pressure and high humidity radiation of the present invention has at least the following advantages:

1) It can realize the hydrogen concentration measurement under the temperature of 170℃, the pressure of 6.5bar, the cumulative irradiation dose of 6.96×10 ⁵ Gy (γ-ray), 7.54×10 ⁵ Gy (β-ray), and 100% high temperature steam environment. Raise the measurement temperature of its hydrogen concentration to 200°C;

2) The hydrogen concentration is measured by means of catalytic electrochemistry, and the measurement electrode terminal adopts solid hydrogen reaction metal, which can react without relying on oxygen, and can also measure the hydrogen concentration in external aerobic and oxygen-free environments;

3) The intrinsically safe circuit design is adopted, and components such as safety barriers are used to effectively ensure the safety of the hydrogen measurement system and reduce the possibility of hydrogen explosion caused by the system itself;

4) The oxygen storage layer is added in the hydrogen measuring element 24, which can effectively release and adjust the gas composition in the hydrogen measuring element 24, prolong the service life, and at the same time seal well, which can prevent the explosive gas in the hydrogen measuring element 24 from reacting with oxygen. ;

5) The working temperature of the hydrogen measuring probe is kept at about 200°C through the heating assembly, which can not only keep the concentrated phosphoric acid in a liquid state for a long time without crystallization, and maintain the electrical conductivity, but also ensure that the hydrogen measuring element 24 is measured at a constant temperature, and a constant temperature is obtained. The hydrogen reaction curve at temperature reduces the influence of external high temperature changes on the measurement.

In different embodiments, the hydrogen concentration measuring device of the present invention that is resistant to high temperature, high pressure and high humidity radiation can also make the following improvements:

1) The hydrogen measurement probe 20 can use the electrochemical measurement principle of phosphoric acid electrolyte as described above, and can also use other electrolytes to achieve measurement, and can also use the hydrogen concentration measurement principle of solid electrolyte. Various materials have new requirements;

2) Please refer to FIG. 10, the counter electrode 244 of the hydrogen measuring element 24 can also adopt a double-layer solid electrode material, for example, one layer adopts the aforementioned counter electrode as the basic counter electrode, and the electrode catalyst can be rhodium, ruthenium, palladium, One or a mixture of one or several metals among iridium, silver, platinum or alloys with other metals, etc., the other layer adopts CeO _2-x or YBa(Co _1-x Al _x ) ₄ O _7+δ or YBaCo ₄ O _7+δ or ceria-zirconia, the two layers together form a counter electrode with a solid oxidant, which improves the conversion efficiency and reduces the dependence on the oxygen storage layer, which can provide a stable oxidant.

Based on the disclosure and teaching of the above specification, those skilled in the art to which the present invention pertains can also make appropriate changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the protection scope of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for convenience of description and do not constitute any limitation to the present invention.

Claims (13)

1. A hydrogen measuring probe resistant to high temperature, high pressure and high humidity radiation, characterized in that:

   It includes a probe shell, a hydrogen measuring element and a fixing assembly. The probe shell is provided with a hydrogen measuring inlet covering a filter screen, and the fixing assembly is used to fix the hydrogen measuring element in the probe shell;

   The hydrogen measuring element adopts a catalytic electrochemical method to measure the hydrogen concentration, and includes a measuring element casing with an insulating layer, a filter permeable membrane, a measuring electrode, a counter electrode, a reference electrode, an electrolyte layer, an oxygen storage layer and a hydrogen measuring element lead wire, Among them, the filter permeable membrane is fixed on one end of the measuring element shell, the oxygen storage layer is fixed on the other end of the measuring element shell, the measuring electrode, the counter electrode and the reference electrode are all arranged inside the measuring element shell; the measuring electrode is set close to the filter permeable membrane, The counter electrode and the reference electrode are set together on the side of the measuring electrode facing away from the filter permeable membrane, and the electrolyte layer is set between the measuring electrode, the counter electrode and the reference electrode, and between the layer where the counter electrode and the reference electrode are located and the oxygen storage layer. The space is the oxygen storage space; the hydrogen measuring element has at least three leads, which are respectively connected with the measuring electrode, the counter electrode and the reference electrode;

   The oxygen storage layer adopts metal oxygen storage and oxygen releasing and producing materials, which can continuously release oxygen.
2. The hydrogen measuring probe according to claim 1, wherein the oxygen storage layer comprises an oxygen release material, an oxygen storage material and a catalytic material, the oxygen release material is calcium peroxide (CaO _{2 )} , and the oxygen storage material is CeO _2-x Or YBa(Co _1-x Al _x ) ₄ O _7+δ or YBaCo ₄ O _7+δ , the catalytic material selects rhodium, ruthenium, palladium, gold, iridium, silver, platinum or an alloy of the aforementioned metals; the oxygen storage layer It also includes a water-absorbing material or a water-absorbing layer is provided on the side of the oxygen storage layer facing the inside of the housing of the measuring element. The water-absorbing material or the water-absorbing layer is used to absorb the moisture in the probe, ensure that the air is relatively dry, and lock the moisture for use by the oxygen storage layer.
3. The hydrogen measuring probe according to claim 1, characterized in that, the casing of the measuring element is made of stainless steel with strong mechanical strength and radiation resistance, the insulating layer prevents the measuring electrode and the counter electrode from conducting, and PEEK or ETFE material is selected.
4. The hydrogen measuring probe according to claim 1, wherein the filter permeable membrane is a semi-permeable membrane with a double-layer structure, comprising an outer selective permeable membrane and an inner selective permeable membrane, and the outer selective permeation membrane The permeable membrane is a PET selective permeation membrane or a dense ceramic membrane, and the inner selective permeation membrane is a palladium alloy membrane or a niobium alloy membrane.
5. The hydrogen measuring probe according to claim 1, wherein the measuring electrode and the counter electrode are metal porous carbon electrode plates, including an electrode support layer and a catalyst layer, and the support material of the electrode support layer is ETFE; The electrode catalyst of the electrode catalyst layer adopts platinum or platinum alloy, and the electrode catalyst of the counter electrode catalyst layer adopts one or a mixture of several metals or alloys with other metals among rhodium, ruthenium, palladium, gold, iridium, silver, and platinum; The reference electrode plays the role of a stable potential zero point, and the same metal porous electrode plate as the measuring electrode is selected.
6. The hydrogen measuring probe according to claim 5, wherein the electrode catalyst of the counter electrode catalyst layer is selected from platinum alloys, preferably platinum-chromium alloys, platinum-titanium alloys, platinum-iron-manganese ternary alloys or platinum-iron-cobalt ternary alloys alloy.
7. The hydrogen measuring probe according to claim 5, wherein the counter electrode further comprises a solid oxidant layer, and the oxidant of the solid oxidant layer adopts CeO _2-x or YBa(Co _1-x Al _x ) ₄ O _7+δ Or YBaCo ₄ O _7+δ or ceria-zirconia.
8. The hydrogen measuring probe according to claim 1, wherein the electrolyte layer adopts 95% to 99% concentrated phosphoric acid as a liquid substance, and is provided with an electrolyte holding material for adsorbing the concentrated phosphoric acid, and the electrolyte holding material comprises: Silicon carbide and ETFE.
9. The hydrogen measuring probe according to claim 1, wherein the hydrogen measuring probe further comprises a heating assembly, and the heating assembly includes a heating support layer, a temperature probe, a temperature probe lead, a heating element and a heating element lead; the heating support layer is The structural support part of the heating assembly, the temperature probe is closely fixed on the heating support layer, and the heating element is a metal heating sheet or a ceramic heater fixed on the heating support layer.
10. The hydrogen measuring probe according to claim 1, characterized in that, the hydrogen measuring probe further comprises a cable gland and an anti-spray assembly, the cable gland is installed on the probe shell, and a high-temperature-resistant and radiation-resistant quick connector is used to ensure The inner space of the probe housing is sealed, and at the same time, the lead wires in the probe housing are fast connected to the cables outside the probe housing; the probe housing includes the probe upper housing and the probe lower housing which are sealed and connected. The spray water is sprayed directly to the hydrogen measurement inlet located in the lower housing of the probe.
11. A hydrogen concentration measuring device that is resistant to high temperature, high pressure and high humidity radiation, characterized in that it includes a pressure sensor for measuring the pressure of the position to be measured, a hydrogen measuring probe for measuring the partial pressure of hydrogen at the position to be measured, and a signal processing and control device. The probe is the hydrogen measuring probe described in any one of claims 1 to 10; the signal processing and control device are respectively connected with the pressure sensor and the hydrogen measuring probe through cables, and are used to collect the signals of the pressure sensor and the hydrogen measuring probe and make them Processed and converted to hydrogen concentration.
12. The hydrogen concentration measuring device according to claim 11, wherein the hydrogen measuring probe signal comprises a hydrogen concentration signal and a temperature signal; the signal processing and control device is located between electronic equipment, and includes a signal input and output component, a processing component and signal remote transmission components; the signal input and output components are connected to the pressure sensor and the hydrogen measuring probe through a cable that is resistant to high temperature and radiation, and are used to collect the pressure signal of the pressure sensor, the hydrogen concentration signal and the temperature signal of the hydrogen measuring probe; processing The component is connected with the signal input and output component, and is used to calculate the hydrogen proportion concentration in the measured gas according to the hydrogen concentration signal and the pressure signal. The signal remote transmission component is used to output the hydrogen proportion concentration to the external user.
13. The hydrogen concentration measuring device according to claim 12, wherein the processing unit is further configured to convert the temperature signal into a heating control signal for controlling the heating element, and the signal input and output unit is further configured to receive the heating control signal and convert the temperature signal into The voltage and current signals which are converted into the heating element are output to the heating element.

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