KR100444844B1 - Electrolytic polishing utilization radioactive contamination meatal type clear system - Google Patents

Abstract

The present invention is a device for removing radioactive material from the metal radioactive waste contaminated by the radioactive material, finely peel off the surface of the metal through the electropolishing process to remove the radioactive contaminants fixed on the metal surface from the target metal It can be recycled or treated as general waste to reduce the amount of radioactive waste of metals generated from nuclear power plants and to prevent or maximize the radiation exposure of decontamination workers involved in decontamination (radioactive decontamination) by conventional water washing. Device.

To this end, it is possible to treat gaseous and liquid radioactive wastes generated during decontamination using a work bench consisting of two electrolytic polishing tanks and one flush and the electropolishing, which can selectively decontaminate stainless steel alloy steel and carbon steel alloy steel. Gas, liquid radioactive waste purifiers, and power supplies for electropolishing, hoods with windows made of lead glass for integrating these devices and preventing worker exposure from radiation emitted from radioactive waste constitute the device of the present invention. .

Description

ELECTROLYTIC POLISHING UTILIZATION RADIOACTIVE CONTAMINATION MEATAL TYPE CLEAR SYSTEM}

The present invention relates to an apparatus for removing and decontaminating radioactive material from metallic radioactive waste by applying a polishing method by decontamination (radioactive decontamination) of metallic radioactive waste generated in a nuclear power plant.

In general, the treatment of metallic radiation pollutants in nuclear power plants has been relied on by decontamination by ultrasonic cleaning or by washing with a brush or scrubbing brush. However, these decontamination methods exist on the surface of metallic radioactive waste. It is only possible to remove the free contaminants, and in the case of sticking contamination, it is not possible to expect a smooth effect, and when the decontamination object has a complicated shape, the decontamination itself is abandoned. In addition, radiation decontamination is accompanied by decontamination because decontamination workers directly handle radioactive contaminants during decontamination by washing with water.

The device according to the present invention is to solve the conventional problems, the object of the present invention is to apply the electropolishing method to the decontamination of the metallic radioactive contaminants to obtain the effect of complete decontamination, liquid, gas radioactive generated during electrolytic decontamination It is to provide a radioactive contamination metals decontamination apparatus using electropolishing that solves the problem of waste disposal.

1 is a conceptual diagram according to the present invention,

2 is an assembled cross-sectional view according to the present invention.

<Description of the symbols for the main parts of the drawings>

1: hood 2: first electrolytic polishing

3: second electrolytic polishing bath 4: water washing tank

5: circulation pump 6: heating and cooling device

7: sintered metal filter 8: ion exchange resin tank

9: gas radioactive waste filtration device 9a: pre-filter

9b: activated carbon filter 9c: Cottrell Purifier

The present invention for achieving the object as described above, two electrolytic polishing baths capable of selectively decontamination of radioactively contaminated metals and carbon steel-based metals and one water for washing the decontaminated metals A work table in which three tanks are lined up, a device for supplying and recovering an electrolyte solution for electrolytic polishing decontamination at the bottom of the work table, a heating and cooling device for controlling the temperature of the electrolyte solution, and a filtration for treating odor and gaseous radioactive waste due to evaporation of the electrolyte solution. Radiation exposure of decontamination workers can be reduced by integrating the device, ion exchange resin tank, and filtration device for the treatment of odor and gaseous radioactive waste due to evaporation of electrolyte in the hood and closing the lead glass window installed in the hood during electrolytic polishing. It is a feature of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a conceptual diagram according to the present invention, Figure 2 is an assembled cross-sectional view according to the present invention. As shown in FIGS. 1 and 2, a first electrolytic polishing bath 2 for decontamination of stainless alloy steel and a second electrolytic polishing bath 3 for decontamination of carbon steels and flushing on a work bench inside the hood 1 are mounted. A washing tank 4 is provided in a row, and a lower portion thereof includes a circulation pump 5 for circulating the electrolyte and a heating and cooling device 6 for matching the electrolyte conditions of the electrolyte.

In addition, between the first and second electrolytic polishing tanks (2) (3) and the circulation pump (5), a sintered metal filter (7) and an ion exchange resin tank for removing radioactive contaminants in the electrolyte during recovery (disposal) of the electrolyte (8) are provided respectively. On the other hand, the upper part of the hood (1) is integrally provided with a gaseous radioactive waste filtration device (9) for the treatment of gaseous radioactive labeling and odor removal, and electrolytic polishing decontamination around the hood (1). A power supply device (not shown) is provided to constitute the present invention. When the window of the hood 1 for the electropolishing decontamination work of the present invention is opened, the power supply device (not shown) is completely switched off. After attaching the radioactive polluted metal to the clasp of the positive electrode (+) plate transfer device, the first electrolytic polishing bath (2) and the second electrolytic polishing bath (3) were selected according to the type of metal, and then the electropolishing target The metal is inserted into the electrolytic polishing bath. Next, the window of the hood 1 is Then, the power supply is switched to stand-by, the message 'Ready' is displayed on the display window on the front of the hood (1), and the unique electrolytic polishing time, voltage and current condition according to the type and size of metal. The voltage controller, current regulator, and timer can be set.When all the conditions are set, the power switch is turned on.The message 'working' is displayed on the front display window of the hood, and electrolytic polishing decontamination At this time, the electrolyte solution is heated by the heating device 6 so as to have appropriate electrolytic conditions, and at the same time by evaporation of the vaporizable radioactive material upon evaporation of the electrolyte solution due to this heating, the gas containing the vapor (Fume) at this time The gas is purified through a filtration device 9 above the hood 1 and discharged to a discharge port by a blower. The gaseous radioactive waste filtration device 9 is a pre-filter 9a. Consists of an activated carbon filter (Activity Charcoal Filter) (9b), Cottrell purifier (Cottrell Precipitator) (9c).

At this time, the pre-filter (9a) is to protect the activity charcoal filter (Activity Charcoal Filter) (9b), the activity charcoal filter (Activity Charcoal filter) (8b) is a smell and 1- Adsorb gaseous radioactive waste generated when decontamination of radionuclides such as 125, and finally, the Cottrell Precipitator (9c) is contaminated particles and residual contaminants passed through the first and second filtration devices. It will function to purify.

The electrolyte heated by the initial heating device is further heated as the electropolishing progresses, so it is necessary to cool the electrolyte in order to meet the appropriate electrolytic conditions, and the temperature sensor (not shown) provided in each electrolytic polishing bath 2,3 When the temperature detected by c) is equal to or higher than the proper temperature, the electrolyte is maintained at the proper temperature by the cooling device 6, and is supplied back to the electrolytic cell by the electrolyte circulation pump 5 to increase the electrolytic salt effect.

When disposing of the electrolyte due to the change in the composition ratio of the electrolyte components and the accumulation of radioactive pollutants due to the repeated electrolytic polishing salt operation, the liquid radioactive waste treatment device provided at the lower part of the work bench is used to filter the radioactively contaminated electrolyte solution into a sintered metal filter ( 7) The large granular radioactive material was filtered through the sintered metal filter (7), and the electrolyte was passed through the ion exchange reaction in the ion exchange resin tank (8) filled with the cation exchange resin and the anion exchange resin at the same time. It will function to remove radioactive material.

When the electrolytic polishing decontamination is completed under the predetermined conditions, the decontamination worker is notified through the buzzer and 'complete' is displayed on the display window.

On the other hand, the radioactive contaminants of the electropolishing decontamination is completed to remove the contaminated electrolyte solution on the surface through the water washing in the washing tank (4), it is determined whether the decontamination by radioactive contamination measurement.

As described above, the electropolishing decontamination apparatus solves the problem of gas and liquid radioactive waste, which is a problem associated with electrolytic polishing decontamination, and thus electrolytic polishing method is applied to radioactive waste decontamination to completely decontaminate radioactive contaminants of metals.

Complete decontamination of radioactive waste of metals can reduce the costs associated with the storage and management of radioactive wastes due to the reduction of metallic radioactive wastes, and can also benefit from the regeneration and recycling of special alloy materials used in nuclear power plants.

With the saturation of its own waste storage facility for each nuclear power plant, the replacement and dismantling of equipment, tanks, pipes, etc., due to the aging of the nuclear power plant is increasing, and the operation time of the first Kori Nuclear Power Plant, which started its first commercial operation, is scheduled to end. Since the shortage of the research reactor (Triga 2) began in 2001, securing the technology for the treatment of metallic radioactive waste can be seen as an urgent step, and decontamination of metallic radioactive waste using the electrolytic polishing method according to the present invention. The device has an appropriate effect in view of the above.

Claims (3)

A first electrolytic polishing bath (2) and a second electrolytic polishing bath (3), which are provided on a work table inside the hood (1) and are capable of selectively decontaminating an alloy steel of a stainless steel system and an alloy steel of a carbon steel system; A washing tank (4) provided at one side of the second electrolytic polishing bath (3) to wash the decontamination object decontaminated in the first electrolytic polishing bath (2) and the second electrolytic polishing bath (3); A heating and cooling device (6) provided at a lower portion of the work table to maintain an appropriate temperature by heating and cooling the electrolyte solution; And A circulation pump 5 provided below the work table to circulate the electrolyte into the first and second electrolytic polishing baths (2) and (3); Radioactive contamination metals decontamination apparatus using electrolytic polishing, characterized in that consisting of. The sintered metal filter (7) and ion exchange between the first and second electrolytic polishing baths (2) and (3) and the circulation pump (5) which can filter sludge produced during the decontamination process. Radioactive contamination metals decontamination apparatus using electropolishing, characterized in that the resin tank (8) is provided. 2. The pre-filter 9a, the activated carbon filter 9b, and the upper portion of the hood 1, which can filter and treat the evaporated gas of the electrolyte generated during the decontamination process and the gas due to the vaporization of contaminants. The apparatus for removing radioactive contamination metals using electropolishing is characterized by further comprising a gaseous radiation waste removing device (9) comprising a coatel purifier (9c).