CN216792099U - Integrated sealed oxygen concentration sensor for liquid lead-bismuth alloy - Google Patents

Integrated sealed oxygen concentration sensor for liquid lead-bismuth alloy Download PDF

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Publication number
CN216792099U
CN216792099U CN202122934887.XU CN202122934887U CN216792099U CN 216792099 U CN216792099 U CN 216792099U CN 202122934887 U CN202122934887 U CN 202122934887U CN 216792099 U CN216792099 U CN 216792099U
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China
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oxygen concentration
stainless steel
bismuth alloy
liquid lead
concentration sensor
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CN202122934887.XU
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牛风雷
梁瑞仙
李小波
盛振华
王译锋
杨凌峰
祁睦然
朱卉平
刘芳
刘洋
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North China Electric Power University
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North China Electric Power University
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    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E30/00Energy generation of nuclear origin
    • Y02E30/30Nuclear fission reactors

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Abstract

The utility model discloses an integrated sealed type liquid lead-bismuth alloy oxygen concentration sensor which mainly comprises a signal unit, an instrument supporting unit and a core oxygen measuring element. A solid oxide electrolyte ceramic probe provided with a reference electrode in the core oxygen measurement element is fixedly arranged in a protective steel sleeve, and the protective steel sleeve is mechanically connected with a stainless steel support cylinder; the lower end part of the wire electrode is inserted into the reference electrode, the upper end of the wire electrode is connected with the signal quick connector, and the signal quick connector is connected with the positive electrode of the signal unit through a connecting wire; the upper end of the stainless steel supporting cylinder is mechanically sealed by a stainless steel sealing outer joint thread of an insulating end socket, one end of the stainless steel sealing outer joint is connected with the negative electrode of the electromotive force signal display instrument through a signal connecting wire, and the other end of the stainless steel sealing outer joint is grounded. When a core oxygen measuring element of the oxygen concentration sensor is inserted into the liquid lead-bismuth alloy to be measured, the signal unit intuitively obtains electromotive force, and the oxygen concentration in the liquid lead-bismuth alloy is obtained by solving according to a relational expression of the electromotive force and the oxygen concentration.

Description

Integrated sealed type liquid lead bismuth alloy oxygen concentration sensor
Technical Field
The utility model relates to the field of oxygen concentration sensors of lead-based coolants of fourth-generation nuclear reactors, in particular to an integrated sealed type liquid lead-bismuth alloy oxygen concentration sensor.
Background
The liquid lead bismuth alloy serving as a preferred material of a spallation target in a subcritical system driven by a fourth-generation reactor lead-based fast reactor coolant and an accelerator has strong corrosivity to a reactor structural material at high temperature, the corrosivity of the liquid lead bismuth alloy is influenced by the oxygen concentration, the corrosion of the liquid lead bismuth alloy to an iron-based metal material can be accelerated when the oxygen concentration is too low, and the pollution of an oxide of the liquid lead bismuth alloy can be caused when the oxygen concentration is too high. Research shows that oxygen exists in the liquid lead bismuth alloy at different temperatures, an area with a compact and uniform oxide layer is formed on the surface of the iron-based metal material due to the oxygen concentration, and the oxide layer can prevent the liquid lead bismuth alloy from further corroding structural steel. Therefore, the accurate measurement of the oxygen content in the liquid lead bismuth alloy is crucial to the control of the oxygen concentration of the liquid lead bismuth alloy. The electrochemical primary battery component capable of measuring the extremely low oxygen concentration dissolved in the liquid lead bismuth alloy coolant system is prepared by utilizing the ion conduction function of the solid oxide electrolyte ceramic, when the coolant system is stabilized at more than 200 ℃, the oxygen partial pressure at two sides of the solid oxide electrolyte is different to generate concentration electromotive force, and the real-time electromotive force is read by a connected voltmeter to realize the online monitoring of the content of the dissolved oxygen in the liquid lead bismuth alloy coolant system.
SUMMERY OF THE UTILITY MODEL
The technical problem solved by the utility model is as follows: the integrated sealed liquid lead-bismuth alloy metal concentration sensor can accurately monitor the dissolved oxygen content in a liquid lead-bismuth alloy coolant system at the temperature of more than 200 ℃ on line, and provides upstream data for controlling the metal concentration of the liquid lead-bismuth alloy.
The technical scheme adopted by the utility model for solving the technical problems is as follows: an integrated sealed type liquid lead bismuth alloy oxygen concentration sensor comprises a signal unit, an instrument supporting unit and a core oxygen measuring element; the signal unit comprises a voltmeter (14), a positive electrode connecting lead (15), a negative electrode connecting lead (13), a grounding lead (16), a signal quick connector (4) and an electrode wire (10); the instrument supporting element comprises a stainless steel supporting cylinder (1) with radiating fins, a sealing flange (5), an inner insulating pipe (6), an insulating seal head (3) and a stainless steel sealing outer joint (2); the core oxygen measuring element comprises a solid oxide electrolyte ceramic probe (12), a reference electrode (11), a protective steel sleeve (9), an inner graphite sealing ring (8) and a graphite gasket (7); a solid oxide electrolyte ceramic probe (12) provided with a quantitative reference electrode (11) in the core oxygen measuring element is fixedly arranged in a protective steel sleeve (9) and is sealed by an inner graphite sealing ring (8), and the protective steel sleeve (9) is mechanically connected with the lower end of the stainless steel supporting cylinder (1) through threads and is sealed by a graphite gasket (7); the lower end of the electrode wire (10) partially wrapped by the inner insulating tube (6) is exposed and inserted into the reference electrode (11), and the upper end of the electrode wire is connected with the signal quick connector (4); the signal quick connector (4) is wrapped and fixed by an insulating seal head (16) and is connected with the positive electrode of a voltmeter (14) through a positive electrode connecting lead (15); the upper end of the stainless steel supporting cylinder (1) is mechanically sealed by a stainless steel sealing outer joint (2) of the insulating seal head (3) in a threaded manner, one end of the stainless steel sealing outer joint (2) is connected with the negative electrode of the voltmeter (14) through a negative electrode connecting wire (13), the other end of the stainless steel sealing outer joint (2) is grounded, and the voltmeter visually obtains the electromotive force of the primary battery assembly.
When a core oxygen measuring element of the oxygen concentration sensor is inserted into the liquid lead bismuth alloy of the oxygen concentration to be measured, the liquid lead bismuth alloy, the solid oxide electrolyte ceramic probe (12), the reference electrode (11), the electrode wire (10), the signal quick connector (4), the positive connecting lead (15), the voltmeter (14), the negative connecting lead (13), the stainless steel sealing outer connector (2), the stainless steel support cylinder (1) and the protective steel sleeve (9) form a complete primary battery loop.
The solid oxide electrolyte ceramic probe (12) is in a crucible shape with a closed bottom end, the type of the material is Yttria Partially Stabilized Zirconia (YPSZ), 5.5mol% of yttria is adopted, and only oxygen ions can migrate through the solid oxide electrolyte ceramic probe (12) when the oxygen concentration sensor works.
The reference electrode (11) is made of Cu/Cu2O, is in a powder shape, has a particle size of 5-10 mu m, has a purity of 99.9%, and has a Cu-Cu 2O mass ratio of 1: 1.
Wherein, the electrode wire (10) adopts tantalum as a material, and the purity is 99.9%.
The No. 1 electrode wire and the No. 2 electrode wire are made of tantalum or molybdenum.
Wherein, the signal display instrument is a voltmeter (14), and a voltmeter with high input resistance (>10G omega) is adopted.
The solid oxide electrolyte ceramic probe (12) and the protective steel sleeve (9) are sealed by an inner graphite sealing ring (8), the protective steel sleeve (9) and the stainless steel supporting cylinder (1) are sealed by a graphite gasket (7), and the purpose of using graphite sealing is to prevent liquid lead bismuth alloy from entering the stainless steel supporting cylinder (1) and the solid oxide electrolyte ceramic probe (12) to cause damage to the oxygen concentration sensor.
The solid oxide electrolyte ceramic probe (12) of the integrated sealed liquid lead-bismuth alloy oxygen concentration sensor needs to be activated at the temperature of more than 300 ℃, and the lowest working temperature is 200 ℃.
Wherein, the upper part of the stainless steel supporting cylinder (1) is provided with heat dissipation fins.
The No. 1 electrode wire is wrapped by the inner insulating tube in the stainless steel shell, and can be prevented from being in contact with the stainless steel shell to cause short circuit.
The electrode wire (10) is wrapped by the inner insulating tube (6) at the position of the stainless steel supporting cylinder (1), and short circuit caused by contact with the stainless steel supporting cylinder (1) can be avoided.
The solid oxide electrolyte ceramic probe (12) is fixedly arranged in a protective steel sleeve (9) and is sealed by an inner graphite sealing ring (8), the protective steel sleeve (9) is mechanically connected with the lower end of the stainless steel supporting cylinder (1) through threads, and is sealed by a graphite gasket (7); the upper end of the stainless steel supporting cylinder (1) is sealed by the combination of the insulating seal head (3) and the stainless steel sealing outer joint (2), and the oxygen concentration sensor has good sealing performance and can isolate the external environment.
The stainless steel supporting cylinder (1) is provided with the sealing flange (5), so that the mounting position of the oxygen concentration sensor can be conveniently adjusted, and the oxygen concentration of the liquid lead-bismuth alloy in the coolant system at different positions and different temperatures can be conveniently measured.
Compared with the prior art, the utility model has the advantages that:
the method adopts the principle of an electrochemical primary battery, takes Cu/Cu2O with known oxygen concentration as a reference electrode, takes the liquid lead bismuth alloy coolant with the oxygen concentration to be measured as a measuring electrode, takes 5.5mol% of Yttria Partially Stabilized Zirconia (YPSZ) as a solid oxide electrolyte, can measure the lowest temperature of 200 ℃, can accurately measure the dissolved oxygen concentration of a non-isothermal liquid lead bismuth alloy coolant system, provides necessary upstream data for controlling the concentration of metal oxide of the liquid lead bismuth alloy, and is beneficial to the long-term operation of the liquid lead bismuth alloy coolant system.
Drawings
FIG. 1 is a schematic diagram of the electrochemical cell of the present invention; FIG. 2 is a schematic diagram of the operation of the present invention; FIG. 3 is a schematic structural view of the present invention;
wherein: the device comprises a stainless steel supporting cylinder (1) with radiating fins, a stainless steel sealing outer joint (2), an insulating seal head (3), a signal quick joint (4), a sealing flange (5), an inner insulating tube (6), a graphite gasket (7), an inner graphite sealing ring (8), a protective steel sleeve (9), an electrode wire (10), a reference electrode (11), a solid oxide electrolyte ceramic probe (12), a negative connecting wire (13), a voltmeter (14), a positive connecting wire (15) and a grounding wire (16).
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments, and all other embodiments obtained by a person skilled in the art without creative efforts based on the embodiments in the present invention belong to the protection scope of the present invention.
As shown in fig. 1, in the embodiment of the present invention, the principle of the electrochemical primary cell is that oxygen ions migrate through the solid oxide electrolyte to generate electromotive force due to the difference in oxygen concentration between the cathode and the anode on both sides of the solid oxide electrolyte.
As shown in the working schematic diagram of the utility model in fig. 2, with Cu/Cu2O with known oxygen concentration as a reference electrode, a liquid lead bismuth alloy coolant with a to-be-measured oxygen concentration as a measurement electrode, and 5.5mol% Yttria Partially Stabilized Zirconia (YPSZ) as a solid oxide electrolyte, when a solid oxide electrolyte ceramic probe is inserted into the liquid lead bismuth alloy with a to-be-measured oxygen concentration, an oxygen ion electromotive force is obtained directly through a high input resistance (>10G Ω) voltmeter, and the dissolved oxygen concentration of the liquid lead bismuth alloy system is obtained by solving the nernst equation.
As shown in the schematic structural diagram of the present invention in fig. 3, an integrated sealed type liquid lead-bismuth alloy oxygen concentration sensor includes a signal unit, an instrument supporting unit and a core oxygen measuring element; the signal unit comprises a voltmeter (14), a positive electrode connecting lead (15), a negative electrode connecting lead (13), a grounding lead (16), a signal quick connector (4) and an electrode wire (10); the instrument supporting element comprises a stainless steel supporting cylinder (1) with radiating fins, a sealing flange (5), an inner insulating pipe (6), an insulating seal head (3) and a stainless steel sealing outer joint (2); the core oxygen measuring element comprises a solid oxide electrolyte ceramic probe (12), a reference electrode (11), a protective steel sleeve (9), an inner graphite sealing ring (8) and a graphite gasket (7).
When the device works, a complete galvanic cell loop is formed by the liquid lead bismuth alloy, the solid oxide electrolyte ceramic probe (12), the reference electrode (11), the electrode wire (10), the signal quick connector (4), the positive connecting lead (15), the voltmeter (14), the negative connecting lead (13), the stainless steel sealing external connector (2), the stainless steel supporting cylinder (1) and the protective steel sleeve (9).
The solid oxide electrolyte ceramic probe (12) of the oxygen concentration sensor needs to be activated at the temperature of more than 300 ℃, and the lowest working temperature is 200 ℃.
Oxygen ion electromotive force is obtained intuitively through a high input resistance (10G omega) voltmeter, the dissolved oxygen concentration of the liquid lead bismuth alloy system is obtained through the Nernst equation, and the dissolved oxygen concentration of the liquid lead bismuth alloy coolant system can be monitored in real time.
As shown in figure 3, the stainless steel supporting cylinder (1) is provided with the sealing flange (5), so that the installation position of the oxygen concentration sensor can be conveniently adjusted, and the oxygen concentration of the liquid lead-bismuth alloy at different positions and different temperatures of a coolant system can be conveniently measured
In summary, the integrated sealed type liquid lead bismuth alloy oxygen concentration sensor provided by the utility model can monitor the dissolved oxygen concentration of the liquid lead bismuth alloy coolant system on line in real time, and provide necessary upstream data for controlling the oxygen concentration of the liquid lead bismuth alloy coolant system.
The above description is only a preferred embodiment of the present invention, and certainly should not be taken as limiting the scope of the utility model, which is defined by the claims and their equivalents.

Claims (12)

1. An integrated sealed type liquid lead bismuth alloy oxygen concentration sensor is characterized by comprising a signal unit, an instrument supporting unit and a core oxygen measuring element; the signal unit comprises a voltmeter (14), a positive electrode connecting lead (15), a negative electrode connecting lead (13), a grounding lead (16), a signal quick connector (4) and an electrode wire (10); the instrument supporting unit comprises a stainless steel supporting cylinder (1) with radiating fins, a sealing flange (5), an inner insulating pipe (6), an insulating seal head (3) and a stainless steel sealing outer joint (2); the core oxygen measuring element comprises a solid oxide electrolyte ceramic probe (12), a reference electrode (11), a protective steel sleeve (9), an inner graphite sealing ring (8) and a graphite gasket (7); a solid oxide electrolyte ceramic probe (12) provided with a quantitative reference electrode (11) in the core oxygen measuring element is fixedly arranged in a protective steel sleeve (9) and is sealed by an inner graphite sealing ring (8), and the protective steel sleeve (9) is mechanically connected with the lower end of the stainless steel supporting cylinder (1) through threads and is sealed by a graphite gasket (7); the exposed part of the lower end of the electrode wire (10) partially wrapped by the inner insulating tube (6) is inserted into the reference electrode (11), and the upper end of the electrode wire is connected with the signal quick connector (4); the signal quick connector (4) is wrapped and fixed by the insulating seal head (3) and is connected with the positive electrode of the voltmeter (14) through the positive electrode connecting wire (15); the upper end of the stainless steel supporting cylinder (1) is mechanically sealed by a stainless steel sealing outer joint (2) of the insulating seal head (3) in a threaded manner, one end of the stainless steel sealing outer joint (2) is connected with the negative electrode of a voltmeter (14) through a negative electrode connecting wire (13), the other end of the stainless steel sealing outer joint (2) is connected with a grounding wire (16), and the voltmeter visually obtains the electromotive force of a primary battery assembly.
2. The integrally sealed liquid lead-bismuth alloy oxygen concentration sensor according to claim 1, wherein when a core oxygen measuring element of the oxygen concentration sensor is inserted into the liquid lead-bismuth alloy to be measured for oxygen concentration, the liquid lead-bismuth alloy, the solid oxide electrolyte ceramic probe (12), the reference electrode (11), the electrode wire (10), the signal quick connector (4), the positive connecting lead (15), the voltmeter (14), the negative connecting lead (13), the stainless steel sealing external connector (2), the stainless steel support cylinder (1) and the protective steel sleeve (9) form a complete galvanic cell loop.
3. The one-piece sealed type liquid lead-bismuth alloy oxygen concentration sensor according to claim 1, wherein the solid oxide electrolyte ceramic probe (12) is in a crucible shape with a closed bottom end, and only oxygen ions can migrate through the solid oxide electrolyte ceramic probe (12) when the oxygen concentration sensor is in operation.
4. The one-piece sealed type liquid lead-bismuth alloy oxygen concentration sensor according to claim 1, wherein the reference electrode (11) is a metal oxide having a known oxygen concentration.
5. The one-piece sealed type liquid lead-bismuth alloy oxygen concentration sensor according to claim 1, wherein the electrode wire (10) is made of tantalum.
6. The one-piece sealed type liquid lead-bismuth alloy oxygen concentration sensor according to claim 1, wherein the voltmeter (14) is a high input resistance voltmeter having a resistance of more than 10G Ω.
7. The one-piece sealed type liquid lead bismuth alloy oxygen concentration sensor according to claim 1, wherein the solid oxide electrolyte ceramic probe (12) and the protective steel sleeve (9) are sealed by an inner graphite sealing ring (8), and the protective steel sleeve (9) and the stainless steel support cylinder (1) are sealed by a graphite gasket (7), the graphite sealing is used for preventing the liquid lead bismuth alloy from entering the stainless steel support cylinder (1) and the solid oxide electrolyte ceramic probe (12) to cause the oxygen concentration sensor to be damaged.
8. The one-piece sealed type liquid lead-bismuth alloy oxygen concentration sensor according to claim 1, wherein the activation is performed at 300 ℃ or more for 30 minutes, and the minimum working temperature is 200 ℃.
9. The one-piece sealed type liquid lead-bismuth alloy oxygen concentration sensor according to claim 1, wherein the stainless steel support cylinder (1) is provided with heat dissipation fins at the upper part.
10. The oxygen concentration sensor of the integrally sealed type liquid lead-bismuth alloy as claimed in claim 1, wherein the wire electrode (10) is wrapped at the stainless steel support cylinder (1) by the inner insulating tube (6) to avoid short circuit caused by contact with the stainless steel support cylinder (1).
11. The integrated sealing type liquid lead-bismuth alloy oxygen concentration sensor according to claim 1, wherein the upper end of the stainless steel support cylinder (1) is sealed by the combination of the insulating seal head (3) and the stainless steel sealing outer joint (2), and the oxygen concentration sensor has good sealing performance and can isolate the external environment.
12. The integrally sealed type liquid lead-bismuth alloy oxygen concentration sensor according to claim 1, wherein the stainless steel support cylinder (1) is provided with a sealing flange (5), so that the installation position of the oxygen concentration sensor can be conveniently adjusted, and the oxygen concentration of the liquid lead-bismuth alloy at different positions and different temperatures of the coolant system can be conveniently measured.
CN202122934887.XU 2021-11-26 2021-11-26 Integrated sealed oxygen concentration sensor for liquid lead-bismuth alloy Expired - Fee Related CN216792099U (en)

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CN202122934887.XU CN216792099U (en) 2021-11-26 2021-11-26 Integrated sealed oxygen concentration sensor for liquid lead-bismuth alloy

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Application Number Priority Date Filing Date Title
CN202122934887.XU CN216792099U (en) 2021-11-26 2021-11-26 Integrated sealed oxygen concentration sensor for liquid lead-bismuth alloy

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CN216792099U true CN216792099U (en) 2022-06-21

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