JPH0648478Y2 - Structure of Electrolytic Dyeing Section for Electrolytic Dyeing Equipment - Google Patents

Description

[Detailed Description of the Invention] (Related industry field) The present invention is used in a nuclear facility without leaking electrolyte solution on various articles, large-scale articles that are difficult to move, metal surfaces such as facility walls, and The present invention also relates to the structure of the electro-dyeing section for the electro-dyeing device capable of performing electro-dyeing while moving the contact surface.

(Prior Art) Nuclear facilities perform decontamination work on metal surfaces for the purpose of preventing an increase in dose due to the accumulation of radioactive substance contamination, temporary storage of unwanted materials, and carrying them out of the controlled area.

At present, many decontamination methods have been proposed, and among them, the electro-deletion method is used as a quick, reliable, and simple method. However, since articles are soaked in an electrolytic solution and decontamination is carried out by applying electricity and anodic dissolution, only objects of a size and shape that can be immersed in an electrolytic solution tank are targeted, and large articles and facilities that are difficult to move. It is considered that the wall surface and the like are not suitable for the electrolytic polishing decontamination method.

On the other hand, there are some in-situ contact methods that perform electrolytic polishing decontamination while moving the cathode while flowing the electrolytic solution, but since the electrolytic solution is run off, the electrolytic solution must be collected on the floor surface. In addition, not only the amount of the electrolytic solution to be used is increased, but also the recovery of the electrolytic solution is difficult. In addition, since it is used for the mirror finishing of the metal surface in the general industry, it is rarely applied to decontamination because it causes the spread of pollution due to the scattering of the electrolytic solution.

Therefore, it is strongly desired to propose an electrolytic polishing decontamination apparatus for a site, which is capable of easily moving the surface of the metal to be decontaminated, on the assumption that the electrolytic solution is collected and circulated at the same time as the decontamination.

In order to meet this demand, the present applicant has previously disclosed an invention entitled "On-site electro-dyeing device" (Japanese Patent Laid-Open No. 62-11).
6299 publication). This consists of a decontamination part that contacts the metal surface and performs decontamination by holding the electrolytic solution, and a circulation system that can perform electrolytic solution suction and filtration processing and discharge the electrolytic solution into the container. The decontamination section includes an inner container having an electrolyte solution suction port, an outer container having an electrolyte solution suction port similarly having an air inlet on the outer periphery, and a plurality of discharge holes for discharging the electrolyte solution. It has a cathode container having a cathode and a pad, and the circulation system sucks the electrolytic solution from the inner container and the outer container, collects the electrolytic solution in the electrolytic solution tank, and circulates continuously through the filter into the cathode. It was done like this.

However, in the decontamination part, the circulating electrolytic solution is discharged from the discharge hole of the cathode container and held in the pad, and is collected from both the inner container and the outer container. By introducing an appropriate amount of air into the container from the intake port, it is possible to prevent the negative pressure in the container from rising excessively and prevent the decontamination device from sticking to it, allowing the decontamination device to move smoothly. Although the desired effect is exhibited, there are problems that the structure of the decontamination part is complicated, and that the application to the decontamination surface having a narrow and uneven surface is insufficient.

(Problems to be solved by devising) The problems of the above-mentioned prior application were solved to simplify the constitution of the decontamination part, and to apply the electro-deletion dyeing device which can be applied not only to a narrow part but also to an uneven surface. It is the one we are trying to provide.

(Solution by the Invention) A cathode container having a plurality of electrolyte discharge holes at its tip, and a suction tube in which the cathode container is surrounded and a tip opening portion is concentrically provided with a suction gap between the cathode container and the cathode container. The outer container provided with the outer container and the pad that covers the open end portion of the outer container and is fastened to the side body of the outer container constitute the electro-dyeing section for the electro-dyeing apparatus.

(Embodiment) In FIG. 1, A is an electrolysis dyeing unit according to the present invention.
B is a circulation system (hereinafter, simply referred to as a circulation system) that discharges and collects the electrolytic solution into the electrolysis dyeing section A. C is a flexible tube that connects the circulation system B and the electrolysis dyeing unit A. The electrolytic solution is sent by the pump 1 through the filter 2 to the electrolysis-dyeing section A. The valve V ₆ is the drain valve of the filter 2. The valves V ₁ and V ₂ adjust the flow rate of the electrolytic solution, and the flow rate can be known by the flow meter 3. Sludge and the like is removed from the electrolytic solution by the filter 2.

The electrolysis solution discharged into the electro-deletion dyeing section A conducts anodic electrolysis on the surface of the decontamination target 5 by passing electricity between the cathode container 4 serving as a cathode and the decontamination target 5 serving as an anode. Here, the anode cable 6 (FIG. 1) is a cable that gives the object to be decontaminated 5 an anode position, and the cathode cable 7 gives the cathode container 4 a cathode position.

The cathode container 4 has a plurality of electrolyte solution discharge holes 4b at its tip, through which the electrolyte solution is discharged. Reference numeral 8 denotes a pad which is attached to the space between the article to be decontaminated 5 and the cathode container 4. The pad 8 has a role of uniformly holding the electrolytic solution.

Next, the electro-dyeing section A will be described. The electro-deletion section A comprises the cathode container 4, the outer container 9 and the pad 8 as described above. The cathode container 4 has a conduit portion 4a for introducing an electrolytic solution,
At the tip of the conduit portion 4a, a large diameter portion 4c having a plurality of discharge holes 4b for discharging an electrolytic solution is formed.

Reference numeral 9 denotes an outer container that surrounds the outside of the cathode container 4, and is provided with a suction tube 10 for sucking air and an electrolytic solution in the side body portion. The tip of the outer container 9 has an annular suction gap 11 between it and the large diameter portion 4c of the cathode container 4. The tip of the outer container 9 is covered with a pad 8, which is fastened to the side body of the outer container 9 by a pad fixing tool 12. As shown in FIG. 4, the pad 8 has a sponge-like shape having a thickness t of about 1/5 to 1/20 of the nozzle opening width W (FIG. 2) in order to retain and pass electrolyte. It has a double structure of an acid resistant resin fiber (for example, polyester resin) 8a and an acid resistant cloth 8b for increasing the liquid holding amount and durability of the pad, and completely covers the opening surface of the outer container 9. .

The outer container 9 is integrated with the conduit portion 4a of the cathode container 4 by, for example, screwing. Reference numeral 13 denotes a terminal block attached to the cathode container 4 at the upper part of the outer container, and the cathode cable 7 is connected to the terminal block via the terminal 14.

As described above, the present invention relates to the structure of the decontamination part of the electro-deletion dyeing device, but it can also be applied as a plating device if the polarities of the electrodes are reversed.

(Function) The electrolytic solution sent from the flexible tube C collects from the conduit portion 4a of the cathode container 4 to the large diameter portion 4c, is discharged from the discharging hole 4b into the pad 8, and wets the pad 8. If the nozzle is not in contact with the material to be decontaminated 5, the pad 8
The electrolyte infiltrating the electrolyte is sucked from the suction gap 11
Recovered faster than 10. Therefore, the electrolyte does not leak out of the nozzle.

When actually performing decontamination, the electro-deletion dyeing part A is to be decontaminated 5
When a surface pressure is applied to the electrode 5 to bring it into contact with the object to be decontaminated 5 through the pad 8, the liquid is not sucked at the tip of the cathode part and the liquid holding power is increased. . Then, a sufficient amount of liquid required for anodic dissolution can be secured, and by applying an electric current to the cathode container 4, electrolysis dyeing is performed.

Further, the electrolytic solution which has been dissolved in the anode is collected from the suction gap 11 between the cathode container 4 and the outer container 9 together with air and the gas generated during the dissolution of the anode. In this case, the substantial area of the suction portion is reduced, the flow velocity of the air sucked from the periphery of the pad 8 is increased, and the electrolytic solution is recovered more quickly, so that the liquid does not leak even during decontamination. Absent.

In this way, since the thickness of the pad 8 allows a space for allowing air to pass between the suction gap 11 and the substance to be decontaminated 5, the negative pressure generated by the suction causes the tip of the electro-deletion portion A to reach the substance to be decontaminated 5. It is possible to perform decontamination while freely moving on the surface of the article to be decontaminated 5 without adsorbing.

Further, regarding the generation of heat during electrolysis, since the electrolytic solution is sucked together with a large amount of air, the thickened electrolytic solution is quickly cooled and the heat accumulation is reduced. Therefore, the current density for the electrode can be made higher than that of the conventional decontamination part.

The electrolytic solution / air / generated gas that has undergone the anode electrolysis passes through the flexible tube C and is sucked into the electrolytic solution tank 15. The electrolyte solution collected in the electrolyte solution tank 15 is recycled again. A liquid level gauge 16 monitors the electrolytic flow rate of the liquid tank 15.

The air and gas separated in the liquid tank 15 are exhausted by the exhaust fan 19, but the mist is removed by the mist trap 17 and the dust is removed by the exhaust filter 18. The exhaust fan 19 has two functions of making the electrolytic solution tank 15 a negative pressure, collecting the electrolytic solution which has completed the anode electrolysis, and sucking and exhausting the collected air and gas. 20 is a DC power supply, and 21 is an inverter for controlling the pump flow rate.

(Effect) 1) The electrolytic solution is sucked together with a large amount of air and cooled rapidly, so that less heat is generated, and the current density for the electrode can be made higher than that of the conventional in-situ contact method to increase the amount of anodic dissolution. .

2) Since a tray for collecting the discharged electrolytic solution is not required, it is possible to decontaminate a large and stationary structure.

3) Since there is no drainage of the electrolytic solution, there is little effect on facilities and equipment other than the decontamination target.

4) Since the electrolytic solution is directly sucked and collected and circulated for use, the amount of the electrolytic solution can be small and the apparatus can be downsized.

5) Since the current used is much smaller than that of the immersion method, the running cost can be reduced.

6) Since it is small and lightweight, it can be operated by a manipulator, etc., and is effective for decontamination in places where access is not possible, such as in cells of radioactive material handling facilities.

7) It is possible to decontaminate objects of various shapes (flat surfaces, curved surfaces, protrusions, etc.) and dimensions (from small articles to large structures), and its application range is wide.

8) The decontamination effect is high due to the synergistic effect of the anodic dissolution and the physical polishing power of the pad.

[Brief description of drawings]

FIG. 1 is an overall explanatory view using the electro-dyeing section according to the present invention. FIG. 2 is a vertical cross-sectional view of the electro-deletion dyeing section, showing a state where the pad is not in contact with the article to be decontaminated. FIG. 3 is a sectional view taken along the line III-III in FIG. FIG. 4 is a sectional view of the pad. FIG. 5 is a drawing similar to FIG. 2 and shows the state during decontamination. In the figure: A ... Electrolytic dyeing section, B ... Circulation system C ... Flexible tube 1 ... Electrolyte circulation pump, 2 ... Filter 3 ... Flowmeter, 4 ... Cathode container 4a ... Conduit section , 4b ...... Discharge hole 4c ...... Large diameter part, 4d ...... Cathode surface 5 ...... Decontamination object, 6 ...... Anode cable 7 ...... Cathode cable, 8 ...... Pad 8a ...... Acid resistant resin fiber, 8b …… Acid resistant cloth 9 …… Outer container, 10 …… Suction tube 11 …… Suction annular gap, 12 …… Pad fixture 13 …… Terminal block, 14 …… Terminal 15 …… Electrolyte tank, 16 …… Liquid level gauge 17 …… Mist trap, 18 …… Exhaust filter 19 …… Ventilator, 20 …… DC power supply 21 …… Inverter, 22 …… Electrolyte recovery pump V ₁ …… Bypass valve for flow adjustment V ₂ …… flow regulating valve V ₃ ...... electrolyte recovery pump valve V ₄ ...... negative pressure regulating valve, V ₅ ...... drain valve V ₆ ...... drain valve, V ₇ Bypass valve for ... a discharge stop valve V ₈ ...... electrolyte recovery pump

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Jun Nakajima 161-2 Muramatsu, Tokai-mura, Naka-gun, Ibaraki Prefecture Inside the Tokai Works, Nuclear Power Agency (56) Reference JP 62-116299 (JP, A)

Claims (1)

[Scope of utility model registration request] 1. A cathode container (4) having a plurality of electrolyte solution discharge holes (4b) at its tip, and a cathode container (4) which surrounds the cathode container (4) and has a tip opening portion between the cathode container (4). Suction gap (11)
Outer container (9) provided with a suction pipe (10) arranged concentrically with each other, and a pad which covers the open end of the outer container (9) and is fastened to the side body of the outer container (9). (8) The structure of the electro-dyeing section for the electro-dyeing device comprising