JP2004117149A - Method and device for electrolytic decontamination for waste material from reprocessing facility - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and a device for the electrolytic decontamination which make it possible to efficiently and simultaneously decontaminate numerous objects to be decontaminated which are waste materials from reprocessing facilities such as end pieces of fuel cladding tubes and whose shapes are different. <P>SOLUTION: A basket 4 made of a titanium material which can be uniformly energized so as to use numerous objects 1 to be decontaminated as anodes and is given a passivation treatment is used in an electrolytic cell 2, and cathodes 5 and 6 are set up on the outer periphery including the bottom and an upper part of the objects 1 to be decontaminated. Oxalic acid which has high solvency power and is excellent in electrical conductivity is used as a decontamination liquid. An ultrasonic vibrator 10 is located in the electrolytic cell 2 to intermittently facilitate the exfoliation of the attachment to the objects 1 to be decontaminated during electrolytic decontamination. Since the titanium basket 4 which is given the passivation treatment is used as an anode conductive material, the differentially-shaped objects to be decontaminated can be uniformly decontaminated through the electrolytic manipulation of the oxalic acid decontamination liquid without the work for electrically connecting the anode to each of the objects 1 to be decontaminated. The impartation of ultrasonic vibration during the electrolytic manipulation enables the decontamination for the back sides and intricately-shaped parts of the differentially-shaped objects 1 to be decontaminated. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and an apparatus for electrodischarge dyeing of reprocessed waste materials, and more particularly to a method for removing a large number of decontaminated objects having different shapes generated from a reprocessing facility such as an end piece for fixing a fuel cladding tube. The present invention relates to an electro-decontamination method and an electro-decontamination apparatus for simultaneously decontaminating efficiently.
[0002]
[Prior art]
The waste materials to which radioactive components constantly generated from the reprocessing facility adhere include various equipment and components such as end pieces for fixing the fuel cladding tubes. There is not much experience in decontamination of these irregular shaped waste materials, and there are many unclear points.
[0003]
Here, an overview of the decontamination method of waste materials in the entire reprocessing facility is given. Generally, a mechanical cleaning method and a chemical decontamination method are often combined, and an electrochemical decontamination method is also applied to some reprocessing facilities.
[0004]
The form of the deposit depends on the location of the reprocessing facility. In the case of an end piece for fixing a fuel cladding tube, a metal or oxide such as uranium oxide UO ₂ , plutonium oxide PuO ₂ , fission products Cs, Sr, Ba, Zr, Nd, Ce, and Mo is present on the inner surface. In many cases, iron oxides such as cladding such as Fe ₂ O ₃ and Fe ₃ O ₄ are attached to the outer surface.
[0005]
Since these deposits are difficult to dissolve in a single solution of an acid, an alkali, an oxidizing agent, a reducing agent, and a complexing agent, the chemical decontamination method uses a plurality of decontamination solutions, raises the temperature, It is necessary to decontaminate each operation repeatedly.
[0006]
Nitric acid, phosphoric acid, oxalic acid, citric acid, tartaric acid, picric acid, etc. are used as acids, sodium hydroxide is used as alkali, and potassium permanganate and permanganic acid are used as oxidizing agents. As a reducing agent, hydrazine is used, and as a complexing agent, oxalic acid, citric acid, EDTA or the like is used.
[0007]
The chemical decontamination method comprises a plurality of steps. First, it is washed with high-pressure water, high-pressure air, and high-pressure steam, and then an acid, an alkali, and a complexing agent are sequentially passed through and stirred. Therefore, the operation of the chemical decontamination method is complicated, and it is necessary to raise the liquid temperature in order to improve the dissolution efficiency. In addition, the disposal of waste liquid often involves complicated operations.
[0008]
On the other hand, the electrochemical decontamination method is, in principle, a method in which a metal base material is dissolved by anodic oxidation to remove attached matter thereon.
[0009]
As a positive electrode for eliminating the work of directly connecting each metal waste and an electrode, a system using titanium, platinum, and an electrode coated with platinum on titanium is known (see Patent Documents 1 and 2). .).
[0010]
[Patent Document 1]
JP-A-10-282296 (page 5, FIG. 4, FIG. 5)
[Patent Document 2]
JP-A-8-68894 (page 4, page 5, FIG. 7)
[Problems to be solved by the invention]
However, in any of the methods disclosed in Patent Documents, the measures for preventing dissolution / deterioration of the positive electrode are insufficient, and there is a problem that the positive electrode itself has a life.
[0011]
There are several methods for combining the energization method and the decontamination liquid. The energization method includes a method in which the object to be decontaminated is placed between the electrodes to polarize the object to be decontaminated and the base material is dissolved by anodic oxidation, and a method in which the object to be decontaminated is directly anodic and oxidized and dissolved. Many are seen. Nitric acid, sulfuric acid, hydrochloric acid and EDTA complexing agents are also used in the decontamination solution.
[0012]
In these decontamination methods, in the former bipolar method, there is a concern that the current efficiency may be reduced due to the current flowing through the electrolyte solution more than the object to be decontaminated. On the other hand, in the direct anode method, it is necessary to connect a terminal to be energized to the object to be decontaminated. In any case, it is difficult to efficiently dissolve in a hollow tube or an irregular decontaminated object.
[0013]
In chemical decontamination and electrochemical decontamination, since various decontamination liquids are used, it is required that the waste liquid treatment is easy and the amount of secondary waste is small.
[0014]
SUMMARY OF THE INVENTION An object of the present invention is to provide a method and an apparatus for electrically decontaminating reprocessed waste materials for efficiently decontaminating a large number of objects to be decontaminated having different shapes simultaneously from reprocessing facility waste materials such as fuel cladding tube end pieces. It is to be.
[0015]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a method for electrodisinfecting reprocessed waste material to which radioactive components are adhered, wherein a passivated titanium basket is used as an anode, and a cathode is arranged on the outer periphery of the titanium basket. A method of placing the object to be decontaminated in the treated titanium basket, applying a direct current to the titanium basket and the cathode in the decontamination solution in the electrolytic cell, and subjecting the object to be decontaminated to electrodischarge, the method of electrodischarging the reprocessed waste material. Suggest.
[0016]
As the anode material, a basket of a passivated titanium material that can evenly supply current to a large number of objects to be decontaminated is used. As a connecting means for turning the object to be decontaminated into an anode, the titanium basket in which titanium oxide TiO ₂ is passivated conducts only the portion in contact with a large number of objects to be decontaminated, and in other portions, It has the property of not conducting.
[0017]
As the cathode material, a fixed cathode is disposed on the side and bottom of the electrolytic cell, and a variable electrode is disposed on the upper part so that current flows uniformly on the front and back of the object to be decontaminated.
[0018]
The present invention also provides a method for electro-discharging reprocessed waste materials to which radioactive components are attached, wherein a mesh-shaped passivated titanium basket is used as an anode, and a cathode is arranged on the outer periphery, bottom, and top of the basket. The object to be decontaminated is placed in the titanium basket that has been treated, and a direct current is applied between the titanium basket and the cathode in the decontamination solution in the electrolytic cell to discharge the object to be decontaminated. Suggest a method.
[0019]
Ultrasonic vibration can be applied to the object to be decontaminated during the electric release dyeing for a short time or intermittently. Ultrasonic vibration is applied intermittently in order to promote the detachment of the deposits on the object to be decontaminated and to suppress the reattachment of the solids.
[0020]
It is desirable to arrange the objects to be decontaminated in a single step so as not to overlap in the titanium basket. This is to ensure that the current flows uniformly on the front and back of the object to be decontaminated.
[0021]
The decontamination solution used in the electrolytic cell is an oxalic acid solution having a concentration of 0.5 mol / l to 5 mol / l. For the decontamination solution used in the electrolytic oxidation operation, oxalic acid having both the action of an acid and a complexing agent and having excellent conductivity is used. Since oxalic acid can be decomposed by ultraviolet irradiation and hydrogen peroxide in waste liquid treatment, only decontaminated substances can be separated and recovered. The advantages of using an oxalic acid solution in the electrolytic oxidation operation are as follows: (1) an action of dissolving a base material or deposits as an acid or a complexing agent; (2) a large conductivity and a current flow during electrolysis; 3) Throwing power, which is an index of the range in which the current reaches, is large, that is, the current also flows to the back surface of the object to be decontaminated, and it is easily dissolved.
[0022]
The current density of the object to be decontaminated during the electrodischarge dyeing is 5 mA / cm ² or more.
[0023]
In order to achieve the above object, the present invention provides an electrolytic cell, a passivated titanium basket disposed as an anode inside the electrolytic cell, a fixed cathode disposed on the outer periphery and bottom of the anode, A variable cathode placed at the top, a decontamination solution introduction system that supplies the decontamination solution into the electrolytic cell, a circulation pump that circulates the decontamination solution during electrolysis, and a passivation placed outside the electrolytic cell A DC power supply that applies a direct current between the treated titanium basket and the fixed and variable cathodes, and a decontamination solution discharge system that is located at the bottom of the electrolytic cell and discharges fine particles that have separated and settled during electrodischarge dyeing We propose an electric decontamination device for reprocessing waste materials.
[0024]
The invention further provides an electrolytic cell, a passivated titanium basket disposed as an anode inside the electrolytic cell, a fixed cathode disposed at the outer periphery and bottom of the anode, and a variable cathode disposed at the top of the anode. A cathode, an ultrasonic vibrator installed inside the electrolytic cell, a decontamination liquid introduction system for supplying the decontamination liquid into the electrolytic cell, a circulation pump for circulating the decontamination liquid during electrolysis, A DC power supply that supplies DC between the passivated titanium basket and the fixed and variable cathodes that is placed outside, and an ultrasonic vibrator that is placed outside the electrolyzer for short or intermittent operation during electrolysis We propose an electrodischarge dyeing apparatus for waste reprocessing waste, which consists of a driven ultrasonic oscillator and a decontamination liquid discharge system that is located at the bottom of the electrolytic cell and discharges fine particles that have separated and settled during electrodischarge dyeing.
[0025]
When ultrasonic vibration is applied to the electrolytic cell, the adhered matter on the back surface of the object to be decontaminated is peeled off by cavitation action, and reattachment of the peeled solid can be suppressed.
[0026]
The titanium basket is a titanium material having a passivation film formed by anodizing using a nitric acid solution as an electrolytic solution.
[0027]
The variable cathode disposed above the object to be decontaminated in the electrolytic cell includes means for changing the position of the object to be decontaminated in accordance with the shape and position of the object.
[0028]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, with reference to FIGS. 1 to 6, an embodiment of a method and an apparatus for electrodisinfecting reprocessed waste material according to the present invention will be described.
[0029]
Embodiment 1
FIG. 1 is a diagram showing a system configuration of an apparatus for electrodisinfecting reprocessing waste material according to the present invention. In the case of this embodiment, the reprocessing waste material is the object 1 to be decontaminated such as an end piece for fixing the fuel cladding tube. The electrolytic cell 2 has a square or cylindrical shape, in which a circulation pump 11 for filling the decontamination liquid 3 from the decontamination liquid introduction system 14 and circulating the decontamination liquid 3 is installed. A passivated titanium basket is disposed as an anode 4 inside the electrolytic cell 2, a fixed cathode 5 is disposed on an outer peripheral portion and a bottom portion of the anode 4, and a variable cathode is disposed on an upper portion of the object 1 to be decontaminated. A cathode 6 is provided. A lid 8 having an exhaust hole 7 for discharging oxygen gas and hydrogen gas generated during electrolysis is installed at the upper part of the electrolytic cell 1, and the electrolytic gas is diluted and discharged by air from an air introduction system 9. It is supposed to. An ultrasonic vibrator 10 is also installed inside the electrolytic cell 2. Outside the electrolytic cell 2, there is a DC power supply 12 for supplying a DC between the anode, that is, the passivated titanium basket 4, the fixed cathode 5, and the variable cathode 6, and a super power source for driving the ultrasonic vibrator 10. A sound wave oscillator 13 is provided. At the bottom of the electrolytic cell 2, a decontamination liquid discharge system 15 for discharging fine particles separated and settled during electrodischarge dyeing is arranged.
[0030]
Prior to the decontamination operation, the fixed cathode 5 is disposed in the electrolytic cell 2, and a passivated titanium basket is disposed therein as the anode 4. The objects 1 to be decontaminated are preferably arranged in a single stage on the titanium basket 4 which has been passivated. From the decontamination liquid introduction system 14, a decontamination liquid of a predetermined concentration is put into the electrolytic cell 2. The variable electrode 6 and the ultrasonic vibrator 10 are mounted at predetermined positions.
[0031]
Next, while the decontamination liquid 3 is circulated by the circulation pump 11, a direct current is supplied from the DC power supply 12 to perform decontamination. During the decontamination, for example, the ultrasonic vibrator 10 is intermittently driven to apply ultrasonic vibration to the object 1 to be decontaminated.
[0032]
Dilution air is supplied from an air introduction system 9 to an electrolytic gas generated during decontamination, that is, a mixed gas of oxygen and hydrogen, and is discharged from an exhaust hole 7.
[0033]
When the decontamination is completed, the decontamination liquid 3 and the fine particles separated during the electrodischarge dyeing are discharged from the decontamination liquid discharge system 15.
[0034]
Embodiment 2
FIG. 2 is a diagram showing a configuration of an electrodischarge dyeing test apparatus for verifying the effect of the present invention. In the present electrodischarge dyeing test apparatus, a mesh-type passivated titanium basket is disposed as an anode 17 inside a cylindrical electrolytic cell 16 having a size of 300φ × 450H. A titanium plate is arranged as a fixed cathode 18, and a variable cathode 19 is arranged on the upper part. The sample 20 to be decontaminated is placed on the passivated titanium basket 17. A stirrer 21 for stirring the decontamination liquid and an ultrasonic vibrator 22 are provided inside the electrolytic cell 16. A DC power supply 23 and an ultrasonic oscillator 24 are provided outside the electrolytic bath 16.
[0035]
The sample 20 to be decontaminated is a sample in which a simulated deposit is attached to an end piece for fixing a fuel cladding tube of an actual machine. The attached sample is immersed in a simulated high-level radioactive liquid waste (containing 16 elements such as Zr, Mo, Nd, Ce, Gd, Ba, Cs, and Sr) at 100 ° C. Is a sample subjected to adhesion treatment for 3 days. The attached matter contained a large amount of oxides of each element, and the thickness was about 20 μm.
[0036]
FIG. 3 is a diagram showing current-voltage characteristics when a stainless tube (SUS304L, 48φ × 80H) is installed on a titanium basket 17 in a 2 mol / l oxalic acid solution and when it is not installed. The energization characteristics of the passivated titanium basket 17 for energization using the sample to be decontaminated as an anode were examined. The basket is a mesh-shaped titanium material, which is subjected to passivation at a current density of 5 mA / cm ² for 5 hours in a nitric acid solution of 4 mol / l to form a zirconium dioxide ZrO ₂ film and passivated. It is.
[0037]
According to FIG. 3, when there is no stainless tube, current slightly flows from a voltage higher than 5 V, whereas when there is a stainless tube, the current flows from around 2 V according to the conductivity of the liquid. Flows. These properties indicate that the passivation film of titanium material has a large electric resistance in oxalic acid solution, but does not come into contact with a different kind of material, especially with a material that is more electric potential than titanium. It indicates that it can be energized if it is.
[0038]
Embodiment 3
FIG. 4 is a characteristic diagram showing the result of examining the decontamination effect only by the electrolytic operation using the simulated waste material. As the sample 20 to be decontaminated, an end piece material for fixing a fuel cladding tube of an actual machine to which a metal component contained in a high-level waste liquid was adhered was used. The decontamination effect was evaluated by measuring the concentrations of Fe, which is the main component of the base material, and Zr and Mo in the deposit components in the electrolytic operation. The cathode was placed at the top of the sample in addition to the outer periphery and the bottom of the sample.
[0039]
The decontamination solution was a 2 mol / l oxalic acid solution, and a current of 10 A was passed for 60 minutes to show the change in the dissolved amount including the solid contents of Fe, Zr, and Mo. Fe was dissolved in proportion to time, and Zr and Mo as deposits showed characteristics of reaching a saturation tendency in 20 minutes.
[0040]
[Comparative Example 1]
FIG. 5 is a characteristic diagram showing a result of examining the decontamination effect only by applying ultrasonic vibration using the simulated waste material. As the sample 20 to be decontaminated, the same end piece material as that used in the third embodiment for fixing the fuel cladding tube of the actual machine to which the metal component contained in the high-level waste liquid was attached was used. The decontamination effect was measured by measuring the concentrations of Fe in the main component of the base material and Zr and Mo elements in the attached matter components in the liquid, similarly to the effect of the electrolytic operation.
[0041]
The decontamination solution is a 2 mol / l oxalic acid solution. Ultrasonic vibration of 25 kHz and 750 W was applied intermittently for 15 minutes, 30 minutes and 45 minutes for each 5 minutes.
[0042]
Fe was dissolved by oxalic acid, and Zr and Mo peeled off when vibration was applied. There is a tendency for the amount of peeling to increase, but the amount of dissolution is very small.
[0043]
As described above, the application of the ultrasonic vibration is effective for detachment and detachment of the attached matter at a site having a complicated shape regardless of the outer surface or the inner surface.
[0044]
Embodiment 4
FIG. 6 is a characteristic diagram showing the result of examining the decontamination effect when the electrolytic operation and the ultrasonic vibration application are combined using the simulated waste material.
[0045]
As the sample 20 to be decontaminated, an end piece material for fixing the fuel cladding tube subjected to the adhesion treatment in the same manner as in Embodiments 4 and 5 was used. The decontamination effect was measured by measuring the concentrations of Fe, Zr, and Mo elements in the liquid in the electrolytic operation and the ultrasonic vibration applying operation.
The cathode was placed at the top of the sample in addition to the outer periphery and the bottom of the sample. The decontamination liquid was a 2 mol / l oxalic acid solution, an electric current of 10 A was passed for 60 minutes, and ultrasonic vibration was applied for 15 minutes, 30 minutes and 45 minutes for 5 minutes each.
[0046]
As shown in FIG. 6, Fe dissolves in proportion to time, as in the third embodiment, and Zr and Mo of the attached matter accelerate dissolution when ultrasonic vibration is applied, and after 60 minutes, the electrolysis of the third embodiment occurs. It showed a greater amount of dissolution than alone.
[0047]
Visual observation after the electrolysis confirmed that there was no deposit on the inside of the end piece for fixing the fuel cladding tube, and that the effect of ultrasonic vibration on the internal decontamination was great.
[0048]
【The invention's effect】
According to the present invention, in the method for decontaminating irregular shaped metal waste from a reprocessing facility such as an end piece for fixing a fuel cladding tube, a passivated titanium basket is used as an anode conductive material. The subject to be decontaminated can be uniformly decontaminated by the electrolytic operation of the oxalic acid decontamination solution without the need to electrically connect the positive electrode to the body. Moreover, the titanium basket has been passivated and has a very long life.
[0049]
In addition, when an operation of applying ultrasonic vibration is performed during the electrolysis operation, decontamination of the back surface or the complex shape portion of the object to be decontaminated becomes possible.
[0050]
Furthermore, after decontamination by electrolytic operation and ultrasonic vibration application in the electrolytic cell, if the decontamination liquid is replaced with pure water and washed in the electrolytic cell, post-treatment can be performed, and the decontamination equipment can be reduced. .
[0051]
When oxalic acid is used as the decontamination liquid, the range in which the current reaches during the electrolytic operation increases. In the treatment of the waste liquid after decontamination, ultraviolet irradiation and decomposition with an oxidizing agent such as hydrogen peroxide become possible, and volume reduction becomes easy.
[Brief description of the drawings]
FIG. 1 is a diagram showing a system configuration of an apparatus for electro-discharging and reprocessing waste materials according to the present invention.
FIG. 2 is a diagram showing a configuration of an electrodischarge dyeing test apparatus for demonstrating the effect of the present invention.
FIG. 3 is a diagram showing current-voltage characteristics when a stainless steel tube is placed on a titanium basket in a 2 mol / l oxalic acid solution and when it is not.
FIG. 4 is a characteristic diagram showing a result of examining a decontamination effect only by an electrolytic operation using a simulated waste material.
FIG. 5 is a characteristic diagram showing a result of examining a decontamination effect only by applying ultrasonic vibration using a simulated waste material.
FIG. 6 is a characteristic diagram showing a result of examining a decontamination effect when an electrolytic operation and ultrasonic vibration application are combined using a simulated waste material.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Decontamination object 2 Electrolysis tank 3 Decontamination liquid 4 Passivated titanium basket (anode)
Reference Signs List 5 Fixed cathode 6 Variable cathode 7 Exhaust hole 8 Lid 9 Air introduction system 10 Ultrasonic transducer 11 Circulation pump 12 DC power supply 13 Ultrasonic oscillator 14 Decontamination liquid introduction system 15 Decontamination liquid discharge system 16 Cylindrical electrolytic cell 17 Anode 18 Fixed cathode 19 Variable cathode 20 Sample to be decontaminated 21 Stirrer 22 Ultrasonic vibrator 23 DC power supply 24 Ultrasonic oscillator

Claims (10)

In the method of electro-release dyeing of reprocessed waste materials with radioactive components attached,
The passivated titanium basket is used as the anode,
Place the cathode on its outer periphery,
Place the object to be decontaminated in the passivated titanium basket,
Applying a direct current to the titanium basket and the cathode in the decontamination solution in the electrolytic cell,
A method for electrodischarging a reprocessed waste material, wherein the object to be decontaminated is electrodischarged. In the method of electro-release dyeing of reprocessed waste materials with radioactive components attached,
Using a mesh-shaped passivated titanium basket as the anode,
The cathode is placed on the outer periphery, bottom and top,
Place the object to be decontaminated in the passivated titanium basket,
Applying a direct current to the titanium basket and the cathode in the decontamination solution in the electrolytic cell,
A method for electrodischarging a reprocessed waste material, wherein the object to be decontaminated is electrodischarged. In the method of electro-decontamination of reprocessing waste material according to claim 1 or 2,
A method for electro-disinfecting reprocessed waste material, wherein ultrasonic vibration is applied to the object to be decontaminated in a short time or intermittently during electro-discharge dyeing. In the method of electrodischarging reprocessing waste material according to any one of claims 1 to 3,
A method of electro-decontamination of reprocessed waste material, wherein the objects to be decontaminated are arranged in one step so as not to overlap in the titanium basket. In the method of electrodischarge dyeing of reprocessing waste material according to any one of claims 1 to 4,
A method of electro-decontamination of reprocessed waste material, wherein the decontamination liquid used in the electrolytic cell is an oxalic acid solution having a concentration of 0.5 mol / l to 5 mol / l. In the method of electro-dyeing reprocessing waste material according to any one of claims 1 to 5,
The method of electrodisinfecting reprocessed waste material, wherein the current density of the object to be decontaminated during electrodischarge dyeing is 5 mA / cm ² or more. An electrolytic cell,
A passivated titanium basket arranged as an anode inside the electrolytic cell,
A fixed cathode disposed on the outer periphery and the bottom of the anode,
A variable cathode disposed above the anode,
A decontamination liquid introduction system for supplying a decontamination liquid into the electrolytic cell,
A circulation pump for circulating the decontamination solution during electrolysis,
A direct current power supply that is disposed outside the electrolytic cell and that supplies a direct current between the passivated titanium basket and the fixed cathode and the variable cathode;
A decontamination apparatus for reprocessing waste material, comprising: a decontamination liquid discharge system disposed at the bottom of the electrolytic cell to discharge fine particles separated and precipitated during electrodischarge dyeing. An electrolytic cell,
A passivated titanium basket arranged as an anode inside the electrolytic cell,
A fixed cathode disposed on the outer periphery and the bottom of the anode,
A variable cathode disposed above the anode,
Ultrasonic vibrator installed inside the electrolytic cell,
A decontamination liquid introduction system for supplying a decontamination liquid into the electrolytic cell,
A circulation pump for circulating the decontamination solution during electrolysis,
A direct current power supply that is disposed outside the electrolytic cell and that supplies a direct current between the passivated titanium basket and the fixed cathode and the variable cathode;
An ultrasonic oscillator that is disposed outside the electrolytic cell and drives the ultrasonic vibrator for a short time or intermittently during electrolysis,
A decontamination apparatus for reprocessing waste material, comprising: a decontamination liquid discharge system disposed at the bottom of the electrolytic cell to discharge fine particles separated and precipitated during electrodischarge dyeing. An electro-decolorizing apparatus for reprocessing waste materials according to claim 7 or 8,
The titanium basket is a titanium material having a passivation film formed by anodic oxidation using a nitric acid solution as an electrolytic solution. An electro-decontamination apparatus for reprocessing waste material according to any one of claims 7 to 9,
The variable cathode disposed above the object to be decontaminated in the electrolytic cell is provided with means for changing its position in accordance with the shape and position of the object to be decontaminated. Release dyeing equipment.

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