Local corrosion monitoring device for air-conditioning water-cooling system of nuclear power plant

Abstract

The utility model discloses a nuclear power plant air conditioner water cooling system local corrosion monitoring device which comprises a T-shaped pipeline, the T-shaped pipeline comprises a first pipe section and a second pipe section, an auxiliary electrode is arranged in the first pipe section, a working electrode is arranged at the axial second end of the second pipe section, and the working electrode comprises a battery cell and an insulating shell. The first end surface of the battery cell is exposed on the inner side of the axial second end of the second pipe section; the auxiliary electrode is connected with the working electrode through a first wire; the working electrode is connected with the electrochemical workstation terminal through a second wire; the working electrode and under-scale corrosion metal in the air-conditioning water-cooling system of the nuclear power plant have the same corrosion environment, and the corrosion rate of the working electrode reflects the under-scale local corrosion rate in the air-conditioning water-cooling system of the nuclear power plant, so that the under-scale anoxic corrosion rate in the air-conditioning water-cooling system of the nuclear power plant can be evaluated in real time; and corresponding protection measures can be taken for local corrosion in the air-conditioning water-cooling system of the nuclear power plant in time.

Description

Technical Field

[0001] The utility model relates to the technical field of nuclear power, in particular to a local corrosion monitoring device for an air conditioning water cooling system of a nuclear power plant. Background Art

[0002] The cooling water in the air conditioning water cooling system of the nuclear power plant dissolves the marine atmosphere with a high salt content during the heat exchange with the marine atmosphere, which makes it highly corrosive to the water system. As the cooling water circulates in the system, the cooling water uniformly corrodes the equipment. At the same time, as the system operation time increases, the reproduction of aquatic organisms, the secretions and scale produced are deposited and attached to the surface of the equipment, thus forming an oxygen concentration difference corrosion cell, causing local corrosion to intensify.

[0003] For uniform corrosion caused by circulating cooling water, the traditional method is to simulate the cooling water quality and working conditions, use an electrochemical workstation to conduct experimental tests, and thus obtain its uniform corrosion rate. However, this method has the disadvantages of being time-consuming and lagging, and cannot obtain the corrosion status of the equipment by cooling water in real time, so it is impossible to take corresponding protective measures against the corrosion of the equipment in time. Furthermore, it is impossible to test the local corrosion rate caused by the oxygen concentration difference corrosion cell, so it is impossible to make an effective assessment of the local corrosion situation, which increases the risk of local corrosion perforation of the equipment. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a local corrosion monitoring device for an air conditioning water cooling system of a nuclear power plant.

[0005] The utility model solves the technical problem by adopting a technical solution: constructing a local corrosion monitoring device for a nuclear power plant air conditioning water cooling system, comprising a T-shaped pipe, wherein the T-shaped pipe comprises a first pipe section and a second pipe section, wherein the first pipe section and the second pipe section have the same outer diameter; an axial first end of the second pipe section is connected to a circumferential side surface of the first pipe section, and the second pipe section is communicated with the first pipe section, and an axial second end of the second pipe section is a closed structure;

[0006] An auxiliary electrode is provided in the first tube segment, and a working electrode is provided at the second axial end of the second tube segment. The working electrode includes a battery cell and an insulating shell wrapped around a portion of the outer circumference of the battery cell, and the first end surface of the battery cell is exposed on the inner side of the second axial end of the second tube segment; the auxiliary electrode is connected to the working electrode through a first wire, and the working electrode is connected to the terminal of the electrochemical workstation through a second wire.

[0007] In some embodiments, the surface area of ​​the auxiliary electrode in contact with the cooling water in the T-shaped pipe is a first surface area;

[0008] The surface area of ​​the working electrode in contact with the cooling water in the T-shaped pipe is a second surface area, and the ratio of the first surface area to the second surface area is greater than or equal to 1000:1.

[0009] In some embodiments, the auxiliary electrode is a honeycomb hollow tube bundle.

[0010] In some embodiments, the axial length of the honeycomb hollow tube bundle is 100 mm, the side length of the hexagon in the honeycomb hollow tube bundle is 15 mm, and the surface area of ​​the auxiliary electrode in contact with the cooling water in the T-shaped pipe is 90000 mm 2 ;

[0011] The diameter of the first end surface of the battery core is 10 mm, and the surface area of ​​the first end surface of the battery core is 78.5 mm 2 .

[0012] In some embodiments, the auxiliary electrode is disposed in the first tube segment and is located at the center line of the first tube segment.

[0013] In some embodiments, the auxiliary electrode is installed in the first pipe segment through a bracket.

[0014] In some embodiments, the working electrode is installed at the center of the end surface of the second axial end of the second tube segment.

[0015] In some embodiments, the insulating shell is a shell made of epoxy resin material.

[0016] In some embodiments, the battery core and the auxiliary electrode are made of the same metal material.

[0017] In some embodiments, the axial length of the second tube segment is at least three times the outer diameter of the first tube segment.

[0018] The implementation of the utility model has the following beneficial effects: a local corrosion monitoring device for a nuclear power plant air conditioning water cooling system comprises a T-shaped pipe, the T-shaped pipe comprises a first pipe section and a second pipe section, the first pipe section and the second pipe section have the same outer diameter; the axial first end of the second pipe section is connected to the circumferential side of the first pipe section, and the second pipe section is connected to the first pipe section, and the axial second end of the second pipe section is a closed structure; an auxiliary electrode is arranged in the first pipe section, and a working electrode is arranged at the axial second end of the second pipe section, the working electrode comprises a battery core and an insulating shell wrapped around a part of the outer periphery of the battery core, and the first end face of the battery core is exposed at the axial second end of the second pipe section. On the inside; the auxiliary electrode is connected to the working electrode through the first wire, and the working electrode is connected to the electrochemical workstation terminal through the second wire. The external electrochemical workstation terminal monitors the anaerobic corrosion rate of the working electrode in real time; the working electrode and the under-scale corroded metal in the air-conditioning water-cooling system of the nuclear power plant have the same corrosion environment, and the corrosion rate of the working electrode reflects the under-scale local corrosion rate in the air-conditioning water-cooling system of the nuclear power plant. Therefore, the under-scale anaerobic corrosion rate in the air-conditioning water-cooling system of the nuclear power plant can be evaluated in real time, which is helpful to take corresponding protective measures against local corrosion in the air-conditioning water-cooling system of the nuclear power plant in time. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solution of the utility model, the utility model will be further described below in conjunction with the accompanying drawings and embodiments. It should be understood that the following drawings only show certain embodiments of the utility model, and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0020] Figure 1 It is a structural schematic diagram of a local corrosion monitoring device for a nuclear power plant air conditioning water cooling system in some embodiments of the utility model;

[0021] Figure 2 yes Figure 1 Detail of the local corrosion monitoring device for the air conditioning water cooling system of a nuclear power plant;

[0022] Figure 3 It is a schematic diagram of the coordination between the auxiliary electrode and the first tube section 11 in some embodiments of the utility model. DETAILED DESCRIPTION

[0023] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific implementation methods of the present invention are now described in detail with reference to the accompanying drawings. In the following description, it should be understood that the directions or positional relationships indicated by "front", "back", "up", "down", "left", "right", "longitudinal", "horizontal", "vertical", "horizontal", "top", "bottom", "inside", "outside", "head", "tail", etc. are based on the directions or positional relationships shown in the accompanying drawings, are constructed and operated in a specific direction, and are only for the convenience of describing the present technical solution, rather than indicating that the device or element referred to must have a specific direction, and therefore cannot be understood as a limitation to the present invention.

[0024] It should also be noted that, unless otherwise clearly specified and limited, the terms such as "installed", "connected", "connected", "fixed", "set" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. When an element is referred to as being "on" or "under" another element, the element can be "directly" or "indirectly" located on the other element, or there may be one or more intermediate elements. The terms "first", "second", "third", etc. are only for the convenience of describing the present technical solution, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", "third", etc. can explicitly or implicitly include one or more of the features. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to the specific circumstances.

[0025] In the following description, specific details such as specific system structures and technologies are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid unnecessary details that hinder the description of the present invention.

[0026] See also Figures 1 to 3 The utility model shows a local corrosion monitoring device for a nuclear power plant air conditioning water cooling system, comprising a T-shaped pipe 10, the T-shaped pipe 10 comprising a first pipe section 11 and a second pipe section 12, the first pipe section 11 and the second pipe section 12 having the same outer diameter and the same inner diameter. The axial first end of the second pipe section 12 is connected to the circumferential side surface of the first pipe section 11, the second pipe section 12 is in communication with the first pipe section 11, and the axial second end of the second pipe section 12 is a closed structure.

[0027] An auxiliary electrode 20 is disposed in the first tube segment 11 , and a working electrode 30 is disposed at the second axial end of the second tube segment 12 . Preferably, the working electrode 30 is installed at the center of the end surface of the second axial end of the second tube segment 12 .

[0028] Furthermore, the working electrode 30 includes a battery cell 31 and an insulating shell 32 wrapped around a portion of the outer periphery of the battery cell 31, and the first end face of the battery cell 31 is exposed on the inner side of the second axial end of the second tube segment 12. The battery cell 31 and the auxiliary electrode 20 are both made of the same metal material, for example, both can be made of platinum metal material. The insulating shell 32 is a shell made of epoxy resin material. It can be understood that the working electrode 30 includes a cylindrical battery cell 31 and epoxy resin (forming an insulating shell 32), and the epoxy resin is used to wrap the battery cell 31, exposing only one end face of the battery cell 31, which is in contact with the cooling water in the second tube segment 12.

[0029] The auxiliary electrode 20 is connected to the working electrode 30 via a first wire 40 , and the working electrode 30 is connected to an electrochemical workstation terminal 60 via a second wire 50 .

[0030] The cooling water may flow in from the inlet 11a1a along the first pipe section 11 at a flow rate v, and flow out from the outlet 11b after passing through the auxiliary electrode 20. The flowing cooling water has sufficient oxygen content, and the auxiliary electrode 20 is in contact with the oxygen-rich cooling water.

[0031] The cooling water at the working electrode 30 at the second axial end of the second pipe section 12 remains stationary, the cooling water cannot be convectively exchanged, the oxygen content of the cooling water is low, and the working electrode 30 is in contact with the anoxic cooling water; the first wire 40 is led out of the first pipe section 11 and is interconnected with the battery cell 31 of the working electrode 30, and an oxygen concentration difference corrosion cell can be formed between the auxiliary electrode 20 and the working electrode 30, the auxiliary electrode 20 is the cathode, and the working electrode 30 is the anode. The corrosion rate of the working electrode 30 can be monitored in real time by using an external electrochemical workstation terminal 60, so as to obtain the rate of anoxic corrosion under scale in the system.

[0032] like Figure 1 As shown, in some embodiments, the axial length of the second pipe segment 12 is at least three times the outer diameter of the first pipe segment 11. For example, the outer diameters (or diameters) d of the first pipe segment 11 and the second pipe segment 12 are both 200 mm, and the axial length of the second pipe segment 12 is 3d, i.e., 600 mm.

[0033] In some embodiments, the surface area of ​​the auxiliary electrode 20 in contact with the cooling water in the T-shaped pipe 10 is the first surface area; the surface area of ​​the working electrode 30 in contact with the cooling water in the T-shaped pipe 10 is the second surface area, and the ratio of the first surface area to the second surface area is greater than or equal to 1000: 1. When the ratio of the surface area of ​​the auxiliary electrode 20 and the working electrode 30 in contact with the cooling water is greater than or equal to 1000: 1, the characteristics of "small anode, large cathode" can be met, and the hypoxic corrosion process under the scale in the system can be better simulated to achieve accurate detection of the local corrosion rate.

[0034] Combination Figure 1 and Figure 3 As shown, the auxiliary electrode 20 is disposed in the first pipe section 11 and is located at the center line of the first pipe section 11. The auxiliary electrode 20 is a honeycomb hollow tube bundle, and the honeycomb hollow tube bundle of the auxiliary electrode 20 has the same axis as the first pipe section 11. Further, the auxiliary electrode 20 can be installed in the first pipe section 11 through a bracket 70. The bracket 70 can be a sheet or plate structure, so that the outer peripheral surface of the auxiliary electrode 20 can also contact the cooling water.

[0035] The axial length of the honeycomb hollow tube bundle is 100 mm, the side length of the hexagon in the honeycomb hollow tube bundle is 15 mm, and the surface area (which can be regarded as the first surface area) of the auxiliary electrode 20 in contact with the cooling water in the T-shaped pipe 10 is 90000 mm 2 The diameter of the first end surface of the battery cell 31 is 10 mm, and the surface area of ​​the first end surface of the battery cell 31 (which can be regarded as the second surface area) is 78.5 mm 2 .

[0036] Specifically, Figure 1 and Figure 2 As shown, the diameter d of the cell 31 in the working electrode 30 is 1 The surface area of ​​the end face G is about 78.5 mm 2 The bundle length l of the auxiliary electrode 20 1 is 100 mm, and the side length of the hexagon in the tube bundle is l 2 = 15 mm, the surface of the auxiliary electrode 20 that can contact the cooling water is about 90000 mm 2 The ratio of the surface area of ​​the auxiliary electrode 20 and the working electrode 30 in contact with the cooling water is greater than 1000:1.

[0037] The local corrosion monitoring device for the air conditioning water cooling system of a nuclear power plant is applied as follows: cooling water flows in from the inlet 11a along the first pipe section 11 at a flow rate v, flows out from the outlet 11b after passing through the honeycomb hollow tube bundle of the auxiliary electrode 20, the flowing cooling water has sufficient oxygen content, and the surface of the honeycomb hollow tube bundle of the auxiliary electrode 20 is in contact with the oxygen-rich cooling water; the cooling water at the working electrode 30 at the bottom of the second pipe section 12 remains stationary, the cooling water cannot be convectively exchanged, the cooling water oxygen content is low, and the end face of the working electrode 30 is in contact with the oxygen-deficient cooling water; the first wire 40 is led out of the first pipe section 11 and the battery core 31 of the working electrode 30 is connected to each other, and an oxygen-concentrated layer is formed between the auxiliary electrode 20 and the working electrode 30. In a differential corrosion cell, the auxiliary electrode 20 is a cathode and the working electrode 30 is an anode; the working electrode 30 is connected to an external electrochemical workstation terminal 60 via a second wire 50, and the external electrochemical workstation terminal 60 monitors the anaerobic corrosion rate of the working electrode 30 in real time; the working electrode 30 and the under-scale corroded metal in the air-conditioning water-cooling system of the nuclear power plant have the same corrosion environment, and the corrosion rate of the working electrode 30 reflects the under-scale local corrosion rate in the air-conditioning water-cooling system of the nuclear power plant, thereby being able to evaluate the under-scale anaerobic corrosion rate in the air-conditioning water-cooling system of the nuclear power plant in real time, which helps to take corresponding protective measures against local corrosion in the air-conditioning water-cooling system of the nuclear power plant in a timely manner.

[0038] It can be understood that the above embodiments only express the preferred implementation methods of the utility model, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the patent scope of the utility model. It should be pointed out that, for ordinary technicians in this field, without departing from the concept of the utility model, the above-mentioned technical features can be freely combined, and several deformations and improvements can be made, which all belong to the protection scope of the utility model. Therefore, all equivalent changes and modifications made to the scope of the claims of the utility model should fall within the scope of the claims of the utility model.

Claims

1. A local corrosion monitoring device for a nuclear power plant air conditioning water cooling system, characterized in that: The invention comprises a T-shaped pipe (10), wherein the T-shaped pipe (10) comprises a first pipe section (11) and a second pipe section (12), wherein the first pipe section (11) and the second pipe section (12) have the same outer diameter; the axial first end of the second pipe section (12) is connected to the circumferential side surface of the first pipe section (11), and the second pipe section (12) is in communication with the first pipe section (11); and the axial second end of the second pipe section (12) is a closed structure; An auxiliary electrode (20) is provided in the first tube section (11); a working electrode (30) is provided at the second axial end of the second tube section (12); the working electrode (30) comprises a battery cell (31) and an insulating shell (32) wrapped around a portion of the outer circumference of the battery cell (31); a first end surface of the battery cell (31) is exposed on the inner side of the second axial end of the second tube section (12); the auxiliary electrode (20) is connected to the working electrode (30) via a first wire (40); and the working electrode (30) is connected to an electrochemical workstation terminal (60) via a second wire (50).

2. The local corrosion monitoring device for the air conditioning water cooling system of a nuclear power plant according to claim 1 is characterized in that: The surface area of ​​the auxiliary electrode (20) in contact with the cooling water in the T-shaped pipe (10) is a first surface area; The surface area of ​​the working electrode (30) in contact with the cooling water in the T-shaped pipe (10) is a second surface area, and the ratio of the first surface area to the second surface area is greater than or equal to 1000:

1.

3. The local corrosion monitoring device for the air conditioning water cooling system of a nuclear power plant according to claim 2 is characterized in that: The auxiliary electrode (20) is a honeycomb hollow tube bundle.

4. The local corrosion monitoring device for the air conditioning water cooling system of a nuclear power plant according to claim 3 is characterized in that: The axial length of the honeycomb hollow tube bundle is 100 mm, the side length of the hexagon in the honeycomb hollow tube bundle is 15 mm, and the surface area of ​​the auxiliary electrode (20) in contact with the cooling water in the T-shaped pipe (10) is 90000 mm 2 ; The diameter of the first end surface of the battery core (31) is 10 mm, and the surface area of ​​the first end surface of the battery core (31) is 78.5 mm 2 .

5. The local corrosion monitoring device for the air conditioning water cooling system of a nuclear power plant according to claim 4 is characterized in that: The auxiliary electrode (20) is arranged in the first pipe section (11) and is located at the center line of the first pipe section (11).

6. The local corrosion monitoring device for the air conditioning water cooling system of a nuclear power plant according to claim 4, characterized in that: The auxiliary electrode (20) is installed in the first pipe section (11) via a bracket (70).

7. The local corrosion monitoring device for air conditioning water cooling system of a nuclear power plant according to any one of claims 1 to 6, characterized in that: The working electrode (30) is installed at the center position of the end surface of the second axial end of the second tube section (12).

8. The local corrosion monitoring device for air conditioning water cooling system of a nuclear power plant according to any one of claims 1 to 6, characterized in that: The insulating shell (32) is a shell made of epoxy resin material.

9. The local corrosion monitoring device for air conditioning water cooling system of a nuclear power plant according to any one of claims 1 to 6, characterized in that: The battery core (31) and the auxiliary electrode (20) are both made of the same metal material.

10. The local corrosion monitoring device for air conditioning water cooling system of a nuclear power plant according to any one of claims 1 to 6, characterized in that: The axial length of the second pipe section (12) is at least three times the outer diameter of the first pipe section (11).

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