An oxygen sensor for liquid metals

Abstract

The utility model discloses a kind of oxygen sensors for liquid metal, including detection part, the sensing end of the detection part is used to extend into liquid metal;The detection part includes oxygen conductor pipe, the oxygen conductor pipe is hollow tubular structure, and the one end for extending into liquid metal is closed, for sensing the oxygen ion in the liquid metal;The other end of the detection part is connected with the one end of electrode lead, the other end of the electrode lead is used to be electrically connected with data acquisition device, to output measurement data.This technical solution relative to existing oxygen sensor, solve the technical problem that oxygen sensor for liquid metal in prior art is slow response, and further lead to the technical problem of low detection sensitivity, the thickness of oxygen conductor pipe is thinned in the utility model, and the response time of oxygen sensor can be reduced to improve measurement sensitivity.

Description

Technical Field

[0001] This utility model relates to the field of oxygen content measurement technology in liquid metals, and specifically to an oxygen sensor for liquid metals. Background Technology

[0002] The oxygen content dissolved in liquid metal is a key parameter affecting the corrosion process. It directly regulates the oxidation behavior of structural material surfaces and the formation of oxide deposits in the coolant.

[0003] Lead-based reactors using liquid lead-bismuth as a coolant are one of the main candidate reactor types for fourth-generation nuclear energy systems due to their excellent nuclear waste transmutation and nuclear fuel breeding capabilities, as well as their high safety and economy. However, the corrosion behavior of lead-bismuth alloys on structural materials is one of the core challenges facing their engineering applications. For liquid lead-bismuth, the dissolved oxygen readily forms lead oxide precipitates.

[0004] Therefore, it is necessary to detect the oxygen concentration dissolved in liquid metal in a timely manner so as to regulate the oxygen concentration in a timely manner, thereby effectively mitigating the corrosion of structural materials by liquid metal, ensuring the smooth flow of coolant circuits, and ultimately extending the service life of key equipment and systems in the reactor.

[0005] However, existing oxygen sensors have a slow response speed, which leads to technical problems such as low detection sensitivity, making it impossible to detect changes in oxygen concentration in liquid metal in a timely manner.

[0006] Therefore, the structure of existing oxygen sensors needs to be improved to increase their response speed. Utility Model Content

[0007] The purpose of this invention is to provide an oxygen sensor for liquid metals, in order to solve the technical problem that existing oxygen sensors for liquid metals have slow response and thus low detection sensitivity.

[0008] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0009] An oxygen sensor for liquid metal includes a detection unit, the sensing end of which is inserted into the liquid metal; the detection unit includes an oxygen conductor tube, which is a hollow tubular structure and is closed at one end for inserting into the liquid metal, for sensing oxygen ions in the liquid metal; the other end of the detection unit is connected to one end of an electrode lead, the other end of which is electrically connected to a data acquisition device to output measurement data.

[0010] Compared to existing oxygen sensors, this technical solution reduces the thickness of the oxygen conductor tube, which can lower the response time of the oxygen sensor and improve measurement sensitivity.

[0011] Furthermore, an outer layer structure is provided around the periphery of the oxygen conductor tube. This outer layer structure is a hollow tubular structure, and its inner wall is either fitted to or spaced apart from the outer wall of the oxygen conductor tube. One end of the oxygen conductor tube extending into the liquid metal is located within the outer layer structure. Correspondingly, the outer layer structure has at least one opening for allowing the oxygen conductor tube to contact the liquid metal. Because the oxygen conductor tube is relatively thin, and because the end of the oxygen conductor tube extending into the liquid metal is located within the outer layer structure (i.e., the end of the oxygen conductor tube does not protrude beyond the outer layer structure), it effectively prevents the oxygen conductor tube from breaking while not hindering its operation.

[0012] Furthermore, the detection unit also includes a reference electrode, which is disposed at the end of the sensing end and located inside the oxygen conductor tube.

[0013] Furthermore, it also includes a heat dissipation pipe, which is sleeved on the other end of the detection unit and the outer periphery of the electrode lead for heat dissipation; it also includes a wiring terminal, which is detachably connected to one end of the heat dissipation pipe, and the other end of the electrode lead can be electrically connected to the data acquisition device through the wiring terminal.

[0014] Furthermore, the other end of the heat dissipation pipe is detachably connected to a metal connector, which is sleeved on the outer periphery of the oxygen conductor pipe, and the other end of the metal connector is detachably connected to the outer layer structure.

[0015] Furthermore, the oxygen conductor tube is made of a zirconium oxide-based solid electrolyte.

[0016] Furthermore, the outer layer is made of one of stainless steel, FeCrAl, or molybdenum alloy.

[0017] Furthermore, the wall thickness of the oxygen conductor tube is less than or equal to 0.5 mm.

[0018] Furthermore, the outer layer structure, the heat dissipation pipe, the terminal block, the electrode lead, and the metal connector are all made of the same metal material.

[0019] Furthermore, a sealing ring is provided around the oxygen conductor tube between the heat dissipation tube and the metal connector to seal and prevent liquid metal or liquid metal vapor from entering the electrode lead portion.

[0020] The technical solution of this utility model has the following beneficial effects: Compared with the existing oxygen sensor, the thickness of the oxygen conductor tube of this utility model has been reduced to less than or equal to 0.5 mm, which can significantly reduce the response time of the oxygen sensor and improve the measurement sensitivity. Attached Figure Description

[0021] To make the purpose, technical solution, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings, wherein:

[0022] Figure 1 This is a schematic diagram of the oxygen sensor measurement scenario of this utility model.

[0023] Figure 2 This is a schematic diagram of the oxygen sensor structure of this utility model.

[0024] Figure 3 for Figure 2 Enlarged view of the structure in area A.

[0025] Figure 4 for Figure 2 Enlarged view of the structure in area B.

[0026] Explanation of reference numerals in the attached figures: 100, oxygen sensor; 102, oxygen conductor tube; 103, electrode lead; 104, outer structure; 105, opening; 106, reference electrode; 108, heat dissipation tube; 109, terminal; 110, metal connector; 111, sealing ring; 200, data acquisition device; 201, external wire; 300, liquid metal. Detailed Implementation

[0027] The technical solutions of some embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments disclosed in this utility model, and not all of them. Based on the embodiments provided in this utility model, all other embodiments obtained by those skilled in the art are within the protection scope of this utility model. It should be noted that the same reference numerals and letters in the drawings represent similar parts. Once a part is defined in one drawing, it will not be defined and explained again in subsequent drawings.

[0028] In practical applications, it has been found that existing oxygen sensors often use solid electrolytes as oxygen ion conductors. However, solid electrolytes are relatively thick, which makes them less prone to damage during use, but the thickness affects the response speed. This invention uses a thin-film solid electrolyte, which can significantly improve the response speed and thus enhance the detection sensitivity of the oxygen sensor.

[0029] This invention can be applied to the measurement of oxygen concentration in liquid metals, solving the technical problem of slow response and low detection sensitivity in existing oxygen sensors for liquid metals. Compared to existing oxygen sensors, the oxygen conductor tube in this invention is thinned to 0.5 mm or less, significantly reducing the oxygen sensor's response time (less than 1 hour, compared to approximately 2-3 hours for existing oxygen sensors) and improving measurement sensitivity.

[0030] To further illustrate the structure of this utility model, the following embodiments are disclosed.

[0031] In some embodiments, please refer to Figure 1 An oxygen sensor 100 for liquid metal is provided, comprising a detection unit, the sensing end of which extends into liquid metal 300; the detection unit includes an oxygen conductor tube 102, which is a hollow tubular structure and has one end closed for extending into the liquid metal to sense oxygen ions in the liquid metal 300; the other end of the detection unit is connected to one end of an electrode lead 103, the other end of which is electrically connected to a data acquisition device 200 to output measurement data. Compared to existing oxygen sensors 100, this technical solution reduces the thickness of the oxygen conductor tube 102, thereby reducing the response time of the oxygen sensor 100 and improving measurement sensitivity.

[0032] The working principle of this technical solution is as follows: The oxygen conductor tube 102 acts as an oxygen ion conductor. During detection, the principle of an electrochemical concentration difference cell is utilized. When there is an oxygen concentration gradient at both ends of the oxygen conductor tube 102, oxygen ions will pass through the oxygen conductor tube 102 from the side with high concentration to the side with low concentration, thus forming an electromotive force that can reflect the difference in oxygen concentration between the two sides. At a certain temperature, the oxygen partial pressure in the reference electrode 106 is constant. Therefore, according to the Nernst equation, the oxygen partial pressure in the measured medium can be obtained by measuring the value of the electromotive force E. Then, according to Henry's law, the oxygen concentration in the liquid metal 300 can be obtained.

[0033] In some embodiments, please refer to Figure 1 The electrode lead 103 is electrically connected to the data acquisition device 200 via an external wire 201.

[0034] In some embodiments, please refer to Figure 2 The oxygen conductor tube 102 is a hollow circular tube structure.

[0035] In some embodiments, please refer to Figure 2 and Figure 4The oxygen conductor tube 102 is surrounded by an outer layer structure 104, which is a hollow tubular structure. The inner wall of the outer layer structure 104 is either fitted to or spaced from the outer wall of the oxygen conductor tube 102. One end of the oxygen conductor tube 102 extending into the liquid metal 300 is located within the outer layer structure 104. Correspondingly, the outer layer structure 104 has at least one opening 105 for allowing the oxygen conductor tube 102 to contact the liquid metal 300. Because the oxygen conductor tube 102 is relatively thin, and the end of the oxygen conductor tube 102 extending into the liquid metal 300 is located within the outer layer structure 104 (i.e., the end of the oxygen conductor tube 102 does not protrude outside the outer layer structure 104), it effectively prevents the oxygen conductor tube 102 from breaking, while not hindering the operation of the oxygen conductor tube 102.

[0036] In some embodiments, please refer to Figure 2 and Figure 4 The detection unit further includes a reference electrode 106, which is disposed at the end of the sensing end and located inside the oxygen conductor tube 102.

[0037] In some embodiments, the reference electrode 106 is made of perovskite powder.

[0038] In some embodiments, please refer to Figure 2 The oxygen sensor 100 also includes a heat sink 108, which is sleeved on the other end of the detection part and the outer periphery of the electrode lead 103 for heat dissipation; it also includes a terminal 109, which is detachably connected to one end of the heat sink 108, and the other end of the electrode lead 103 can be electrically connected to the data acquisition device 200 through the terminal 109.

[0039] In some embodiments, the terminal 109 is made of metal. During testing, grounding the terminal 109 can eliminate some interference signals.

[0040] In some embodiments, the other end of the heat dissipation pipe 108 is detachably connected to a metal connector 110, the metal connector 110 is sleeved on the outer periphery of the oxygen conductor pipe 102, and the other end of the metal connector 110 is detachably connected to the outer layer structure 104.

[0041] In some embodiments, the other end of the metal connector 110 is threaded to the outer structure 104.

[0042] In some embodiments, the oxygen conductor tube 102 is made of a zirconium oxide-based solid electrolyte.

[0043] In some embodiments, the oxygen conductor tube 102 is made of one of the following: calcium oxide stabilized zirconia ceramic, yttrium oxide stabilized zirconia ceramic, ytterbium oxide stabilized zirconia ceramic, and scandium oxide stabilized zirconia ceramic. Yttrium oxide stabilized zirconia ceramic is preferred.

[0044] In some embodiments, the outer layer structure 104 is made of one of stainless steel, FeCrAl, or molybdenum alloy.

[0045] In some embodiments, the wall thickness of the oxygen conductor tube 102 is less than or equal to 0.5 mm, and the outer diameter of the oxygen conductor tube 102 is 2.5~3 mm. Correspondingly, the outer wall of the oxygen conductor tube is fitted and fixedly connected to the inner wall of the outer layer structure. In specific implementations, the oxygen conductor tube is prepared by depositing a film on the inner wall of the outer layer structure using methods such as electrochemical deposition, sol-gel method, plasma spraying method, or chemical conversion film technology. These preparation methods all employ mature processes in the prior art and will not be described in detail here.

[0046] In some embodiments, the outer layer structure 104 has a wall thickness of 0.3~1mm and an outer diameter of 5~7mm.

[0047] In some embodiments, please refer to Figure 2 and Figure 3 A sealing ring 111 is provided around the oxygen conductor tube 102 between the heat dissipation tube 108 and the metal connector 110 to seal and prevent liquid metal 300 or liquid metal 300 vapor from entering the electrode lead 103.

[0048] In some embodiments, the sealing ring 111 is preferably a graphite sealing ring 111.

[0049] In some embodiments, the liquid metal 300 is liquid lead-bismuth.

[0050] In some embodiments, the outer structure, the heat sink, the terminal block, the electrode leads, and the metal connectors are all made of the same metal material. This is to eliminate the thermoelectric potential between the components, avoid measurement errors caused by the thermoelectric potential, and make the measured values ​​more accurate.

[0051] This utility model is described through several embodiments. In the description of this utility model, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to has a specific orientation, or is constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the disclosure of this utility model. Unless the context requires otherwise, throughout the specification and claims, the term "comprising" is interpreted as open and inclusive, that is, "including, but not limited to." The terms "first" and "second" are only used to distinguish different descriptive objects and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. In the description of the embodiments disclosed in this utility model, unless otherwise stated, "a plurality of" means two or more.

[0052] In the accompanying drawings, the thickness of layers and regions has been enlarged for clarity. Therefore, variations in shape relative to the drawings are contemplated due to factors such as manufacturing techniques and / or tolerances. Consequently, exemplary embodiments should not be construed as limited to the shapes of the regions shown herein, but rather include shape deviations caused, for example, by manufacturing processes. For instance, etched areas shown as rectangular would typically have curved features. Therefore, the regions shown in the drawings are schematic in nature, and their shapes are not intended to show the actual shapes of areas of the device, nor are they intended to limit the scope of the exemplary embodiments.

[0053] The above description is merely a specific embodiment disclosed in this utility model, but the scope of protection disclosed in this utility model is not limited thereto. Any changes or substitutions conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the scope of protection disclosed in this utility model. Therefore, the scope of protection disclosed in this utility model should be determined by the scope of the claims.

Claims

1. An oxygen sensor for liquid metal, characterized in that, The device includes a detection unit, the sensing end of which is inserted into liquid metal; the detection unit includes an oxygen conductor tube, which is a hollow tubular structure and is closed at one end for inserting into the liquid metal, for sensing oxygen ions in the liquid metal; the other end of the detection unit is connected to one end of an electrode lead, the other end of which is electrically connected to a data acquisition device to output measurement data.

2. The oxygen sensor for liquid metal according to claim 1, characterized in that, The oxygen conductor tube is surrounded by an outer layer structure, which is a hollow tubular structure. The inner wall of the outer layer structure is either fitted to or spaced apart from the outer wall of the oxygen conductor tube. One end of the oxygen conductor tube that extends into the liquid metal is located inside the outer layer structure. Correspondingly, the outer layer structure has at least one opening for allowing the oxygen conductor tube to contact the liquid metal.

3. The oxygen sensor for liquid metal according to claim 1 or 2, characterized in that, The detection unit also includes a reference electrode, which is disposed at the end of the sensing end and located inside the oxygen conductor tube.

4. The oxygen sensor for liquid metal according to claim 2, characterized in that, It also includes a heat dissipation pipe, which is sleeved on the other end of the detection unit and the outer periphery of the electrode lead for heat dissipation; It also includes a terminal block, which is detachably connected to one end of the heat sink, and the other end of the electrode lead can be electrically connected to the data acquisition device through the terminal block.

5. The oxygen sensor for liquid metal according to claim 4, characterized in that, The other end of the heat dissipation pipe is detachably connected to a metal connector, which is sleeved on the outer periphery of the oxygen conductor pipe, and the other end of the metal connector is detachably connected to the outer layer structure.

6. The oxygen sensor for liquid metal according to claim 1, characterized in that, The oxygen conductor tube is made of zirconium oxide-based solid electrolyte.

7. The oxygen sensor for liquid metal according to claim 2, characterized in that, The outer layer is made of one of the following materials: stainless steel, FeCrAl, or molybdenum alloy.

8. The oxygen sensor for liquid metal according to claim 1 or 2, characterized in that, The wall thickness of the oxygen conductor tube is less than or equal to 0.5 mm.

9. The oxygen sensor for liquid metal according to claim 5, characterized in that, The outer layer structure, the heat dissipation pipe, the terminal block, the electrode lead, and the metal connector are all made of the same metal material.

10. The oxygen sensor for liquid metal according to claim 5, characterized in that, A sealing ring is fitted around the outer periphery of the oxygen conductor tube between the heat dissipation pipe and the metal connector.

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