Reference electrode suitable for high-temperature and high-pressure nuclear environment

Abstract

The embodiment of the invention discloses a reference electrode suitable for a high-temperature and high-pressure nuclear environment, the reference electrode comprises a ceramic core body tube, an electrode wire, a solid electrolyte and a sealing assembly, and materials for preparing the solid electrolyte comprise KCl, MgCl. 6H2O and Al2O3. On the basis, in the working process of the reference electrode, when the temperature of the reference electrode is increased at a relatively high temperature, crystal water in MgCl. 6H2O molecules is gradually removed, so that KCl and MgCl are dissolved in the crystal water, an ion transmission channel is provided through porous Al2O3, directional transmission of ions is realized, and after the temperature is recovered to normal temperature, the crystal water is combined with the MgCl molecules to form a hydrate, so that the performance of the reference electrode is improved. And the ORP measurement accuracy, the electrode maintenance convenience and the service life can be further improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of electrochemical sensors, and in particular to a reference electrode suitable for high temperature and high pressure nuclear environments. Background Art

[0002] As a key method of water quality control in nuclear reactor systems, water quality monitoring is mainly achieved through water chemistry monitoring systems. Among them, the reference electrode is the core measurement component of water chemistry monitoring instruments such as pH meters and ORP meters, and is also an important component of water chemistry monitoring systems. It is widely used in nuclear power plants, thermal power plants, chemical industry, metallurgy, scientific research and other fields. In nuclear reactor water chemistry monitoring, through the effective monitoring of water chemistry indicators such as pH and ORP, the control of water chemistry indicators can be achieved, thereby reducing the corrosion of nuclear reactor materials.

[0003] For the primary coolant of the reactor operating under high temperature and high pressure conditions, the physical and chemical properties of the solution are significantly different from those at room temperature due to long-term exposure to high temperature and high pressure hydrothermal environment. Among them, the influence of temperature and pressure on the true value of the water chemical index measurement is the most obvious, and its change is directly related to the corrosion and stress corrosion behavior of nuclear materials. The material failure problem caused by chemical corrosion has an important impact on the operating safety and reliability of key systems and equipment of nuclear reactors. The use of high temperature and high pressure water chemical instruments can instantly and effectively measure water quality indicators in situ online, and can improve measurement accuracy, simplify the water quality monitoring system process, and reduce the size of the equipment and space occupation. It is of great significance to feedback the authenticity of the water quality operation of nuclear reactors and improve the effective monitoring and control of water quality operation.

[0004] The reference electrode is the core component of the water quality monitoring system. It is limited by technical difficulties such as poor material stability under high temperature and high pressure conditions, prominent electrochemical effects between different materials, significantly reduced reliability and accuracy of measurement results, and the sealing structure of the electrode is prone to aging and failure under high temperature and high pressure conditions, thereby reducing the service life. Traditional reference electrodes can only be used in low temperature and low pressure or low temperature and high pressure environments. At present, the domestic water quality indicators in high temperature and high pressure water chemical systems are measured after traditional cooling and pressure reduction treatment, which cannot effectively guarantee the timeliness and accuracy of the acquisition of nuclear reactor water quality operation indicators. In addition, this technology has problems such as large system space occupation, complicated system processes and long construction period, which are inconsistent with the development requirements of nuclear reactor devices. Its application is restricted and brings challenges to the effective monitoring and control of nuclear reactor water quality operation. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0006] In view of this, the present application embodiment proposes a reference electrode suitable for a high temperature and high pressure nuclear environment, comprising:

[0007] Ceramic core tube;

[0008] An electrode wire, the electrode wire being inserted into the ceramic core tube;

[0009] A solid electrolyte, the solid electrolyte is filled in the ceramic core tube and is located around the electrode wire;

[0010] A sealing component, the sealing component is connected to the ceramic core tube, and is used to seal the ceramic core tube, and / or to seal the electrode wire, and / or to seal between a reference electrode suitable for a high temperature and high pressure nuclear environment and an external environment;

[0011] Wherein, the materials for preparing the solid electrolyte include KCl, MgCl·6H2O and Al2O3.

[0012] In a feasible embodiment, the material for preparing the ceramic core tube includes: yttria-stabilized zirconia ceramic, wherein the Y2O3 doping amount is about 9% to 25%;

[0013] The materials used to prepare the electrode wire include Ag and AgCl.

[0014] In a feasible embodiment, the material for preparing the solid electrolyte also includes ZrO2.

[0015] In a feasible embodiment, the molecular ratio of KCl, MgCl·6H2O and Al2O3 is 2:1.5:1 to 2:3:5.

[0016] In a feasible implementation manner, the sealing assembly includes: a sealing object, and the sealing object includes:

[0017] A ceramic tube and a cement filler, wherein the electrode wire extends out through one end of the ceramic core tube, and the ceramic tube and the cement filler are used to seal the electrode wire.

[0018] In a feasible implementation, the reference electrode suitable for high temperature and high pressure nuclear environment further includes:

[0019] A protective sleeve is sleeved on the ceramic core tube.

[0020] In a feasible implementation manner, the sealing assembly includes:

[0021] A casing flange, wherein the casing flange is sleeved on the protective casing;

[0022] A first graphite gasket is sleeved on the protective sleeve, and the sleeve flange abuts against the first graphite gasket. When the reference electrode is assembled, the external environment and the sleeve flange jointly squeeze the first graphite gasket to achieve sealing between the reference electrode and the external environment.

[0023] In a feasible implementation manner, the sealing assembly includes:

[0024] A ferrule, the ferrule being sleeved on one end of the protective sleeve;

[0025] A second graphite gasket, which is sleeved on the protective sleeve and abuts against the ferrule;

[0026] An electrode cap, wherein the electrode cap is sleeved on the ferrule;

[0027] A gasket, wherein the gasket is sleeved on the protective sleeve, the electrode cap abuts against the gasket, and the gasket abuts against the second graphite gasket;

[0028] A clamping ring, the clamping ring is arranged between the electrode cap and the clamping sleeve;

[0029] The ferrule, the electrode cap, the gasket and the clamping ring squeeze the second graphite gasket to achieve sealing of the end of the protective sleeve.

[0030] In a feasible implementation manner, the sealing assembly further includes:

[0031] A compression sleeve, the compression sleeve is arranged between the gasket and the electrode cap;

[0032] A hybrid gasket is arranged at the end of the ceramic core tube. The compression sleeve and the gasket squeeze the hybrid gasket to achieve sealing between the ceramic core tube and the external environment.

[0033] In a feasible implementation, the reference electrode suitable for high temperature and high pressure nuclear environment further includes:

[0034] A cooling water jacket connected to the electrode;

[0035] An insulating layer, wherein the insulating layer is sleeved on the electrode wire passing through the ceramic core tube;

[0036] The sealing assembly further comprises:

[0037] A sealing nut and a third graphite gasket, wherein the third graphite gasket is arranged in the electrode cap, and the sealing nut passes through the electrode cap and abuts against the third graphite gasket.

[0038] Compared with the prior art, the present invention has at least the following beneficial effects:

[0039] The reference electrode suitable for high temperature and high pressure nuclear environment provided in the embodiment of the present application includes a ceramic core tube, an electrode wire, a solid electrolyte and a sealing component, wherein the material for preparing the solid electrolyte includes KCl, MgCl·6H2O and Al2O3. Based on this, in the working process of the reference electrode suitable for high temperature and high pressure nuclear environment, when the temperature of the reference electrode suitable for high temperature and high pressure nuclear environment rises at a higher temperature, the crystal water in the MgCl·6H2O molecule gradually escapes, so that KCl and MgCl are dissolved in the crystal water, and the ion transmission channel is provided by the porous Al2O3 to realize the directional transmission of ions. After the temperature is restored to room temperature, the crystal water is combined with the MgCl molecule to form a hydrate, which can further improve the ORP measurement accuracy, electrode maintenance convenience and service life. Combined with the setting of the sealing component, the reference electrode suitable for high temperature and high pressure nuclear environment has a firm structure, good response performance, strong environmental adaptability, convenient maintenance, long service life and can work stably at 300℃ high temperature and 15.5MPa high pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0041] Figure 1 A schematic structural diagram of a reference electrode suitable for a high temperature and high pressure nuclear environment according to an embodiment of the present application.

[0042] in, Figure 1 The corresponding relationship between the reference numerals and the component names is as follows:

[0043] 1 cooling water jacket, 2 screws, 3 sealing nuts, 4 electrode wires, 5 third graphite gaskets, 6 electrode caps, 7 compression sleeves, 8 gaskets, 9 hybrid gaskets, 10 ferrules, 11 protective sleeves, 12 ceramic core tubes, 13 sleeve flanges, 14 solid electrolytes, 15 plugging materials, 17 retaining rings, 18 second graphite gaskets, 19 first graphite gaskets. DETAILED DESCRIPTION

[0044] In order to better understand the above-mentioned technical scheme, the technical scheme of the embodiments of the present application is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical scheme of the embodiments of the present application, rather than limitations on the technical scheme of the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments may be combined with each other.

[0045] like Figure 1 As shown, the embodiment of the present application proposes a reference electrode suitable for a high temperature and high pressure nuclear environment, comprising: a ceramic core tube 12; an electrode wire 4, the electrode wire 4 is inserted in the ceramic core tube 12; a solid electrolyte 14, the solid electrolyte 14 is filled in the ceramic core tube 12, and is located on the peripheral side of the electrode wire 4; a sealing component, the sealing component is connected to the ceramic core tube 12, and is used to seal the ceramic core tube 12, and / or seal the electrode wire 4, and / or seal the reference electrode suitable for a high temperature and high pressure nuclear environment and the external environment. Among them, the materials for preparing the solid electrolyte 14 include KCl, MgCl·6H2O and Al2O3.

[0046] The reference electrode suitable for high temperature and high pressure nuclear environment provided in the embodiment of the present application includes a ceramic core tube 12, an electrode wire 4, a solid electrolyte 14 and a sealing component, wherein the material for preparing the solid electrolyte 14 includes KCl, MgCl·6H2O and Al2O3. Based on this, in the working process of the reference electrode suitable for high temperature and high pressure nuclear environment, when the temperature of the reference electrode suitable for high temperature and high pressure nuclear environment rises at a higher temperature, the crystal water in the MgCl·6H2O molecule gradually escapes, so that KCl and MgCl are dissolved in the crystal water, and the ion transmission channel is provided by porous Al2O3 to realize the directional transmission of ions. After the temperature is restored to room temperature, the crystal water is combined with the MgCl molecule to form a hydrate, which can further improve the ORP measurement accuracy, electrode maintenance convenience and service life. Combined with the setting of the sealing component, the reference electrode suitable for high temperature and high pressure nuclear environment has a firm structure, good response performance, strong environmental adaptability, convenient maintenance, long service life and can work stably at 300°C high temperature and 15.5MPa high pressure.

[0047] The reference electrode suitable for high temperature and high pressure nuclear environment provided in the embodiment of the present application adopts KCl-MgCl·6H2O polytype solid electrolyte 14, with KCl as the hydrophilic material, MgCl·6H2O adjusting the moisture content in the electrode core, changing the existing saturated potassium chloride solution as the internal reference solution, when the temperature rises, the crystallization water of MgCl·6H2O escapes, so that KCl is dissolved in the crystallization water, and after the temperature is lowered, the crystallization water combines with the MgCl molecules to maintain the stability of the electrolyte, which can further improve the environmental adaptability, electrode maintenance convenience and service life of the reference electrode suitable for high temperature and high pressure nuclear environment.

[0048] like Figure 1 As shown, in a feasible implementation manner, the material for preparing the ceramic core tube 12 includes: yttria-stabilized zirconia ceramic, wherein the Y2O3 doping amount is about 9% to 25%.

[0049] In this technical solution, a pattern of a ceramic core tube 12 is further provided, and the material for preparing the ceramic core tube 12 may include yttria-stabilized zirconia ceramics, wherein the Y2O3 doping amount is about 9% to 25%, based on which the ceramic core tube 12 can have high strength, high chemical stability and strong corrosion resistance, and can significantly improve the service life of the reference electrode suitable for high temperature and high pressure nuclear environment. When the temperature of the high temperature aqueous solution is higher than 185°C, the YSZ ceramic film can be used as an ion conductor, has good ion conduction ability, and realizes the equilibrium state inside the reference electrode suitable for high temperature and high pressure nuclear environment, which can significantly enhance the ion transmission efficiency, improve the electrolyte stability of the reference electrode suitable for high temperature and high pressure nuclear environment and the thermal conductivity of the electrode core, reduce the contact potential caused by temperature gradient and concentration gradient, and improve the measurement accuracy, environmental adaptability, electrode maintenance convenience and service life of the reference electrode suitable for high temperature and high pressure nuclear environment.

[0050] It can be understood that the ceramic core tube 12 prepared by yttria-stabilized zirconia ceramics, in which the Y2O3 doping amount is about 9% to 25%, has a microporous permeability function, so under high temperature and high pressure working conditions, the working fluid can penetrate into the ceramic core tube 12, heat and dissolve the KCl and MgCl·6H2O solid electrolyte 14 inside the ceramic core tube 12. Thus, the solution environment under the working state is connected to the Ag / AgCl electrode wire 4, forming the anode in the online ORP test device.

[0051] In a feasible implementation manner, the material for making the electrode wire 4 includes Ag and AgCl.

[0052] In this technical solution, materials for preparing the electrode wire 4 are further provided. The materials for preparing the electrode wire 4 include Ag and AgCl. The Ag / AgCl electrode wire 4 has the characteristics of small solubility, good stability and reversibility in the high-temperature and high-pressure aqueous solution system, and the electrode can be well protected even in the presence of hydrogen. Therefore, it is more suitable for use in a high-temperature and high-pressure environment than other electrodes.

[0053] In some examples, the preparation of Ag / AgCl wire can include three methods. They are: direct chlorination, electrolytic chlorination and thermal decomposition chlorination. Among them, the Ag / AgCl electrode prepared by electrolytic chlorination is less sensitive to light, not easy to decompose, and the preparation method is simple and easy. Therefore, in this technical solution, the electrolytic chlorination method is used to prepare a silver chloride film on the surface of the silver wire. First, the silver wire with a purity of 99.99% is surface pretreated, including removing surface oxides, degreasing, activation and cleaning; the platinum electrode is used as an auxiliary electrode to connect to the negative electrode of the power supply, and the treated silver wire is connected to the positive electrode of the power supply; the silver wire and the platinum electrode are placed at 25°C, and a proper amount of direct current is passed through the HCI solution. After a certain period of time, the silver wire needs to be shaken during the period to remove the hydrogen generated during the electrolysis process. After the electrolysis is completed, the electrode is rinsed with distilled water and placed in a saturated KCI solution for standby use. A small amount of AgCI powder is added to the solution to prevent the AgCI film on the electrode from dissolving, and an Ag / AgCl reference electrode suitable for high temperature and high pressure nuclear environment is prepared.

[0054] like Figure 1 As shown, in some examples, the preparation and filling of the solid electrolyte 14 may include the following steps: KCl and MgCl·6H2O are used as hydrophilic materials, and KCl, MgCl·6H2O and Al2O3 are fully ground in a mortar and added to the YSZ ceramic core tube 12, and the prepared Ag / AgCl electrode wire 4 is inserted, and then extruded. A mixture of a common ceramic short tube with a diameter of 2 to 4 mm and silicate cement slurry is filled at the upper end of the ceramic core tube 12 filled with electrolyte, and the solid electrolyte 14 and the skeleton material mixture in the ceramic tube are compacted and sealed in the ceramic core tube 12; at the outlet where the electrode wire 4 passes through the top of the ceramic core tube 12, a common ceramic short tube is mixed with a silicate cement slurry mixture and compacted and sealed, and the packaging of the solid electrolyte 14 is completed.

[0055] In a feasible embodiment, the material used to prepare the solid electrolyte 14 also includes ZrO2.

[0056] In this technical solution, ZrO2 can also be filled in the solid electrolyte 14. Specifically, it can be ZrO2 fiber. Based on this, Al2O3 and ZrO2 fiber can be used as the skeleton material of solid electrolysis. KCl and MgCl·6H2O are used as the solid electrolyte 14, which can enhance the ion transmission efficiency, improve the electrolyte stability and the thermal conductivity inside the electrode core, reduce the contact potential caused by temperature gradient and concentration gradient, improve the measurement accuracy, and reduce the frequency of electrode maintenance.

[0057] In a feasible embodiment, the molecular ratio of KCl, MgCl·6H2O and Al2O3 is 2:1.5:1 to 2:3:5.

[0058] In this technical solution, the dosage ratio of the material of the solid electrolyte 14 is further provided, based on which the amount of crystal water released can be controlled to facilitate the dissolution of KCl and MgCl in the crystal water, while ensuring sufficient ion transmission channels to achieve directional transmission of ions, enhance ion transmission efficiency, improve electrolyte stability and thermal conductivity inside the electrode core, reduce contact potential caused by temperature gradient and concentration gradient, improve measurement accuracy, and reduce electrode maintenance frequency.

[0059] like Figure 1 As shown, in a feasible implementation manner, the sealing assembly includes: a sealant 15 , the sealant 15 includes: a ceramic tube and a cement filler, the electrode wire 4 extends out through one end of the ceramic core tube 12 , and the ceramic tube and the cement filler are used to seal the electrode wire 4 .

[0060] In this technical solution, the structural composition of the sealing component is further provided. The sealing component may include a sealing material 15. The sealing material 15 includes a ceramic tube and a cement filler. The solid electrolyte 14 can be sealed, compacted and sealed in the ceramic core tube 12 through the arrangement of the ceramic tube and the cement filler, thereby improving the sealing effect of the electrode wire 4 and preventing the solid electrolyte 14 from overflowing.

[0061] In some examples, for sealing effect, the length of the ceramic tube may be 2-4 mm.

[0062] In some examples, in order to ensure sealing strength, the cement filler may be made of a silicate cement slurry material.

[0063] In some examples, in order to improve the sealing effect, the volume ratio of the ceramic tube and the cement filler can be 1:1, and adding the filler consisting of the ceramic tube to the cement filler can improve the strength and firmness of the filler.

[0064] like Figure 1 As shown, in a feasible implementation, the reference electrode suitable for high temperature and high pressure nuclear environment further includes: a protective sleeve 11, and the protective sleeve 11 is sleeved on the ceramic core tube 12. In this way, the ceramic core tube 12 can be protected, and the service life of the reference electrode suitable for high temperature and high pressure nuclear environment can be further improved.

[0065] like Figure 1 As shown, in a feasible embodiment, the sealing assembly includes: a sleeve flange 13, which is sleeved on the protective sleeve 11; a first graphite gasket 19, which is sleeved on the protective sleeve 11, and the sleeve flange 13 abuts against the first graphite gasket 19. When the reference electrode suitable for a high temperature and high pressure nuclear environment is assembled, the external environment and the sleeve flange 13 jointly extrude the first graphite gasket 19 to achieve sealing between the reference electrode suitable for a high temperature and high pressure nuclear environment and the external environment.

[0066] In this technical solution, a structural composition of a sealing component is further provided. The sealing component may include multiple groups of sealing structures, wherein one group of sealing structures may include a sleeve flange 13 and a first graphite gasket 19. The sleeve flange 13 and the first graphite gasket 19 are both sleeved on the protective sleeve 11. When a reference electrode suitable for a high-temperature and high-pressure nuclear environment is assembled, the sleeve flange 13 and the autoclave circulation cell may jointly extrude the first graphite gasket 19 to achieve sealing between the protective sleeve 11, the autoclave circulation cell and the external environment, thereby improving the sealing effect of the reference electrode suitable for a high-temperature and high-pressure nuclear environment.

[0067] In a feasible embodiment, the sealing assembly includes: a ferrule 10, which is sleeved on one end of a protective sleeve 11; a second graphite gasket 18, which is sleeved on the protective sleeve 11 and abuts against the ferrule 10; an electrode cap 6, which is sleeved on the ferrule 10; a gasket 8, which is sleeved on the protective sleeve 11, and the electrode cap 6 abuts against the gasket 8, and the gasket 8 abuts against the second graphite gasket 18; a retaining ring 17, which is arranged between the electrode cap 6 and the ferrule 10; wherein the ferrule 10, the electrode cap 6, the gasket 8 and the retaining ring 17 squeeze the second graphite gasket 18 to achieve end sealing of the protective sleeve 11.

[0068] In this technical solution, a structural composition of a sealing component is further provided. The sealing component may include multiple groups of sealing structures, wherein one group of sealing structures may include a ferrule 10, a second graphite gasket 18, an electrode cap 6, a gasket 8 and a retaining ring 17. The electrode cap 6, the gasket 8, the ferrule 10 and the retaining ring 17 may jointly extrude the second graphite gasket 18 sleeved on the upper end of the protective sleeve 11, thereby achieving sealing between the upper end of the protective sleeve 11 and the external environment, and improving the sealing effect of the protective sleeve 11 and the ceramic core tube 12.

[0069] It is understandable that in order to improve the corrosion resistance and high temperature resistance, the electrode cap 6, the gasket 8, the ferrule 10 and the clamping ring 17 can all be made of stainless steel.

[0070] In a feasible embodiment, the sealing assembly also includes: a compression sleeve 7, which is arranged between the gasket 8 and the electrode cap 6; a hybrid gasket 9, which is arranged at the end of the ceramic core tube 12, and the compression sleeve 7 and the gasket 8 squeeze the hybrid gasket 9 to achieve sealing between the ceramic core tube 12 and the external environment.

[0071] In this technical solution, a structural composition of a sealing component is further provided. The sealing component may include multiple groups of sealing structures, wherein one group of sealing structures may include a compression sleeve 7 and a hybrid gasket 9. The compression sleeve 7 and the gasket 8 may jointly extrude the hybrid gasket 9 to achieve sealing between the ceramic core tube 12 and the external environment.

[0072] It can be understood that the hybrid gasket 9 can be a hybrid gasket 9 of graphite and PTFE, which can further improve the sealing effect.

[0073] In a feasible implementation, the reference electrode suitable for high temperature and high pressure nuclear environment further includes: a cooling water jacket 1 connected to the electrode; and an insulating layer, which is sleeved on the electrode wire 4 passing through the ceramic core tube 12 .

[0074] In this technical solution, the reference electrode suitable for high temperature and high pressure nuclear environment can also include an insulating layer. An insulating layer can be provided on the outside of the non-connected wire portion of the electrode wire 4 that passes through the ceramic core tube 12. The insulating layer includes an insulating heat-resistant coating layer and a polytetrafluoroethylene heat shrinkable tube sleeved on the insulating heat-resistant coating layer. Such a setting can ensure the reliability of the reference stand-alone communication.

[0075] In this technical solution, the reference electrode suitable for high temperature and high pressure nuclear environment may further include a cooling water jacket 1, which can be used to cool the reference electrode suitable for high temperature and high pressure nuclear environment, thereby further improving the performance of the reference electrode suitable for high temperature and high pressure nuclear environment.

[0076] like Figure 1 As shown, in a feasible embodiment, the sealing assembly also includes: a sealing nut 3 and a third graphite gasket 5, the third graphite gasket 5 is arranged in the electrode cap 6, the sealing nut 3 passes through the electrode cap 6 and abuts against the third graphite gasket 5, and the insulating layer is sleeved on the ceramic core tube 12.

[0077] In this technical solution, a structural composition of a sealing component is further provided. The sealing component may include multiple groups of sealing structures, wherein one group of sealing structures may include a sealing nut 3 and a third graphite gasket 5. Based on this, the insulating layer and the protective sleeve 11 can be sealed again by the sealing nut 3 and the third graphite gasket 5, thereby improving the sealing effect.

[0078] In some examples, the gasket 8 and the second graphite gasket 18 sleeved on the ceramic core tube 12 are on the convex shoulder of the through hole with thick upper part and thin lower part in the ferrule 10, a concave cavity is provided in the middle of the lower part of the nut, the lower thread of the nut matches the thread on the inner wall of the coarse hole in the upper part of the ferrule 10, the convex end face of the lower end of the nut squeezes the second graphite gasket 18 sleeved on the ceramic core tube 12, and the concave end face in the middle of the nut squeezes the polytetrafluoroethylene gasket 8 provided on the outlet of the ceramic core tube 12, the ceramic core tube 12 with the above-mentioned sealing device is inserted into the stepped through hole of the autoclave, an annular groove is provided on the perforated convex shoulder, and the first graphite gasket 19 is provided therein, the lower end face shape of the ferrule 10 matches the stepped through hole shape of the autoclave, and the lower end face abuts against the first graphite gasket 19, and a three-level extrusion sealing structure is formed by the first graphite gasket 19, the gasket 8, the second graphite gasket 18 and the mixed gasket 9. The sealing effect can be improved.

[0079] Example

[0080] like Figure 1 As shown, an embodiment of the present application provides a reference electrode suitable for a high-temperature and high-pressure nuclear environment. The reference electrode suitable for a high-temperature and high-pressure nuclear environment includes a ceramic core tube 12 containing Y2O3 which is sealed at one end and open at the other end. An Ag / AgCl electrode wire 4 is inserted in the ceramic core tube 12. A solid mixture electrolyte of KCl, MgCl·6H2O, and Al2O3 is filled around the Ag / AgCl electrode wire 4 inside the ceramic core tube 12. The solid mixture of KCl, MgCl·6H2O, and Al2O3 is mixed in a certain molecular ratio. The Ag / AgCl electrode wire 4 is buried in the mixture of KCl, MgCl·6H2O, and Al2O3. The upper end of the Ag / AgCl electrode wire 4 that passes through the ceramic tube is an Ag wire for connecting a physical wire or directly used as a physical wire.

[0081] The ceramic core tube 12 is filled with ZrO2 fibers in a mixture of KCl, MgCl·6H2O, and Al2O3, and a mixture of a ceramic tube with a diameter of 2 to 4 mm and a cement filler is filled on the ceramic core tube 12, so that the solid electrolyte 14 of the KCl, MgCl·6H2O, and Al2O3 mixture is compacted and sealed in the ceramic core tube 12; the compression sleeve 7 and the gasket 8 are squeezed and mixed to form a compression sleeve 7 and a gasket 8 to squeeze the gasket 9 formed by the mixture of the ceramic tube and the cement filler at the outlet of the top of the ceramic core tube 12, so as to realize the connection between the ceramic core tube 12 and the outer The sealing of the external environment; an insulating layer is provided on the outside of the electrode wire 4 that passes through the non-connected wire part of the ceramic core tube 12, and the insulating layer is composed of an insulating temperature-resistant coating layer and an external polytetrafluoroethylene heat shrink tube. A sealing structure is provided outside the insulating layer, and the sealing is achieved by squeezing the third graphite gasket 5 on the insulating layer through the screw 2, the sealing nut 3 and the electrode cap 6; the sealing between the protective sleeve 11 and the external environment is achieved by the graphite gasket 8 squeezed on the upper end of the protective sleeve 11 by the electrode cap 6, the gasket 8, the ferrule 10, and the clamping ring 17; in addition, a cooling water jacket 1 is provided outside the electrode cap 6.

[0082] The molecular ratio of the solid electrolyte mixture of KCl, MgCl·6H2O, and Al2O3 is about 2:1.5:1 to 2:3:5. The mixture of KCl, MgCl·6H2O, and Al2O3 may be filled with cement: water in a ratio of about 1:1, and the volume ratio of the ceramic core tube 12 and the cement slurry is about 1:1. Adding the filler formed by the ceramic short tube to the cement can improve the strength and firmness of the filler.

[0083] Since the inner tube of the YSZ ceramic core tube 12 material has microporous permeability, the working fluid can penetrate into the ceramic core tube 12 under high temperature and high pressure working conditions, heating and dissolving the KCl and MgCl·6H2O solid electrolyte 14 inside the ceramic core tube 12. Thus, the solution environment under the working state is connected to the Ag / AgCl electrode wire 4, forming the anode in the online test device.

[0084] The reference electrode suitable for high temperature and high pressure nuclear environment provided in this embodiment has at least the following beneficial effects:

[0085] (1) The YSZ-Ag / AgCl-KCl-MgCl·6H2O type solid-state electrode is used, with KCl and MgCl·6H2O as solid electrolytes14 and porous Al2O3 and ZrO2 fibers as electrolyte skeleton materials to enhance the ion transmission efficiency, improve the electrolyte stability and thermal conductivity inside the electrode core, reduce the contact potential caused by temperature gradient and concentration gradient, improve measurement accuracy, and reduce the frequency of electrode maintenance.

[0086] (2) KCl-MgCl·6H2O polytype solid electrolyte 14 is used, KCl is used as the hydrophilic material, and MgCl·6H2O is used to adjust the moisture content in the electrode core. The existing saturated potassium chloride solution is changed as the internal reference solution. When the temperature rises, the crystal water of MgCl·6H2O is released, so that KCl is dissolved in the crystal water. When the temperature drops, the crystal water combines with the MgCl molecules to maintain the stability of the electrolyte. This can further improve the environmental adaptability, electrode maintenance convenience and service life of the reference electrode suitable for high temperature and high pressure nuclear environment.

[0087] (3) The reference electrode suitable for high temperature and high pressure nuclear environment adopts a multiple sealing structure, which has the advantages of reliable sealing and convenient maintenance, ensuring the service reliability of the titanium-plated reference electrode suitable for high temperature and high pressure nuclear environment in high temperature and high pressure water environment.

[0088] In the present invention, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance; the term "plurality" refers to two or more, unless otherwise clearly defined. The terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0089] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by terms such as “upper”, “lower”, “left”, “right”, “front” and “back” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation, and therefore, cannot be understood as a limitation on the present invention.

[0090] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0091] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A reference electrode suitable for high temperature and high pressure nuclear environment, characterized in that: include: Ceramic core tube; An electrode wire, the electrode wire being inserted into the ceramic core tube; A solid electrolyte, the solid electrolyte is filled in the ceramic core tube and is located around the electrode wire; A sealing component, the sealing component is connected to the ceramic core tube, and is used to seal the ceramic core tube, and / or seal the electrode wire, and / or seal the reference electrode and the external environment; Wherein, the materials for preparing the solid electrolyte include KCl, MgCl·6H2O and Al2O3.

2. The reference electrode suitable for high temperature and high pressure nuclear environment according to claim 1, characterized in that: The material for preparing the ceramic core tube includes: yttria-stabilized zirconia ceramics, wherein the Y2O3 doping amount is about 9% to 25%; The materials used to prepare the electrode wire include Ag and AgCl.

3. The reference electrode suitable for high temperature and high pressure nuclear environment according to claim 1, characterized in that: The material for preparing the solid electrolyte also includes ZrO2.

4. The reference electrode suitable for high temperature and high pressure nuclear environment according to claim 1, characterized in that: The molecular ratio of KCl, MgCl·6H2O and Al2O3 is 2:1.5:1 to 2:3:

5.

5. The reference electrode suitable for high temperature and high pressure nuclear environment according to any one of claims 1 to 4, characterized in that: The sealing assembly comprises: a blocking object, and the blocking object comprises: A ceramic tube and a cement filler, wherein the electrode wire extends out through one end of the ceramic core tube, and the ceramic tube and the cement filler are used to seal the electrode wire.

6. The reference electrode suitable for high temperature and high pressure nuclear environment according to any one of claims 1 to 4, characterized in that: Also includes: A protective sleeve is sleeved on the ceramic core tube.

7. The reference electrode suitable for high temperature and high pressure nuclear environment according to claim 6, characterized in that: The sealing assembly comprises: A casing flange, wherein the casing flange is sleeved on the protective casing; A first graphite gasket is sleeved on the protective sleeve, and the sleeve flange abuts against the first graphite gasket. When the reference electrode is assembled, the external environment and the sleeve flange jointly squeeze the first graphite gasket to achieve sealing between the reference electrode and the external environment.

8. The reference electrode suitable for high temperature and high pressure nuclear environment according to claim 6, characterized in that: The sealing assembly comprises: A ferrule, the ferrule being sleeved on one end of the protective sleeve; A second graphite gasket, which is sleeved on the protective sleeve and abuts against the ferrule; An electrode cap, wherein the electrode cap is sleeved on the ferrule; A gasket, wherein the gasket is sleeved on the protective sleeve, the electrode cap abuts against the gasket, and the gasket abuts against the second graphite gasket; A clamping ring, the clamping ring is arranged between the electrode cap and the clamping sleeve; The ferrule, the electrode cap, the gasket and the clamping ring squeeze the second graphite gasket to achieve sealing of the end of the protective sleeve.

9. The reference electrode suitable for high temperature and high pressure nuclear environment according to claim 8, characterized in that: The sealing assembly further comprises: A compression sleeve, the compression sleeve is arranged between the gasket and the electrode cap; A hybrid gasket is arranged at the end of the ceramic core tube. The compression sleeve and the gasket squeeze the hybrid gasket to achieve sealing between the ceramic core tube and the external environment.

10. The reference electrode suitable for high temperature and high pressure nuclear environment according to claim 9, characterized in that: Also includes: A cooling water jacket connected to the electrode; An insulating layer, wherein the insulating layer is sleeved on the electrode wire passing through the ceramic core tube; The sealing assembly further comprises: A sealing nut and a third graphite gasket, wherein the third graphite gasket is arranged in the electrode cap, and the sealing nut passes through the electrode cap and abuts against the third graphite gasket.

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