JPH0611600A - Processing method for contaminated water containing radioactive material - Google Patents

Abstract

PURPOSE:To obtain a method capable of processing contaminated water simply together with later processing of radioactive waste by making a particular sheet absorb the contaminated water including radioactive material. CONSTITUTION:Special water absorbing pulp and the like wrapped with permiable cloth having a form stability contains an organic water absorber agent with semi-solidification characteristic and good water absorbability. After making it absorb water, the semi-solidified sheet is processed as radioactive waste.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a method for treating contaminated water containing radioactive substances which are radioactive wastes generated in nuclear power plants.

[0002]

2. Description of the Related Art Conventionally, among various radioactive wastes containing radioactive materials generated in nuclear power plants, polluted water containing radioactive materials generated during inspection and repair of pipes, valves, pumps, etc. of each system is It is normal to wipe off normal towels as a rag at the site of inspection and repair work.

[0003]

However, the ordinary towels having the above-mentioned rags do not have sufficient water absorbency, and the contaminated water absorbed may leach out from the towels and spread the contamination of radioactive substances. Therefore, it is necessary to wipe off the contaminated water using a large number of towels. Furthermore, towels containing contaminated water are inconvenient to handle and should be easily treated as radioactive waste. There were problems such as being difficult.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, in which an organic water-absorbing agent, which absorbs water and becomes semi-solid, is carried. Using a sheet made by encapsulating water-absorbent pulp with a water-permeable cloth having morphological stability, the contaminated water containing radioactive substances is absorbed into the sheet, and the sheet is semi-solidified as it is. It is characterized by processing as.

In the present invention, the sheet used to absorb the contaminated water containing the radioactive substance is a nonwoven fabric made of a water-absorbent pulp carrying an organic water-absorbing agent which absorbs water and semisolidifies. As described above, the organic water-absorbing agent that absorbs water and becomes semi-solid is a hydrophilic polymer that retains adsorbed water as it is. Is preferable, and a starch-graft copolymer which is excellent in water absorption especially to nuclear reactor water containing boric acid is preferable. Incidentally, in order to carry the organic water-absorbing agent on the water-absorbent pulp, for example, a thin absorbent paper should be spread evenly over a thinly-rolled water-absorbent cotton-like pulp and then uniformly supported on a thin absorbent paper. It suffices if it is sandwiched, and by further covering it with a water-permeable cloth having morphological stability such as non-woven fabric, the water-absorbent pulp can be stably handled as having great shrink resistance and wrinkle resistance. It will be a sheet in the form of a gull.

Therefore, inspection of piping, valves, pumps, etc. of each system of the nuclear power plant using the above-mentioned seat,
If the contaminated water containing radioactive substances generated during repair is wiped off, the contaminated water will be absorbed by the water-absorbent pulp through the water-permeable cloth having sheet shape stability. Is quickly absorbed by the organic water-absorbing agent having excellent water-absorbing property carried on the water-absorbing pulp, and with this absorption, the organic water-absorbing agent contaminates the entire sheet after some time due to its characteristics. It is a semi-solid product that does not leach water.

Therefore, since the semi-solidified sheet is easy to handle, if it is transferred as radioactive waste to the incinerator as it is for incineration, the constituent material of the sheet is made of organic matter and semi-solid matter. Since it is burned like ordinary dust and incinerated with good workability, its ash should be treated in the same manner as other radioactive wastes in a state free from radioactive contamination by the conventional method. .

[0008]

Example A granular saponified starch-grafted polyacrylonitrile copolymer as an organic water-absorbing agent which absorbs water and becomes semi-solid and is excellent in water-absorbing property is spread into a cloth shape having a length of 300 mm, a width of 600 mm and a thickness of about 2 mm. Using a sheet that is evenly supported on absorbent cotton-like pulp, sandwiched between absorbent papers with a thickness of about 1 mm, and the whole is covered with a non-woven fabric made of polyethylene fiber with excellent chemical resistance The contaminated water containing the substance was wiped off at the site where it was generated and absorbed, and after a few minutes, the semi-solidified sheet was transferred to a dust incinerator and subjected to an incineration process for burning and ashing. The sheet used to wipe off the contaminated water is 900 to 1
It absorbed about 000 cc of contaminated water and showed about 20 times the absorbency compared with the ordinary towel cloth.

[0009]

As is apparent from the above description, the present invention allows an organic water-absorbing agent which is semi-solidified by water absorption to be carried on polluted water mainly containing radioactive substances generated in a nuclear power plant. The water-absorbent pulp is covered with a non-woven fabric or other water-permeable cloth having the same morphological stability to absorb the contaminated water without spreading the contamination of radioactive substances under excellent absorption capacity. In addition, it has good workability and can be easily incinerated as radioactive waste and other appropriate treatments, and mainly contaminated water generated during inspection and repair of pipes, valves, pumps, etc. of each system of a nuclear power plant. It is of great industrial value as it can be easily processed.

Claims (1)

[Claims] 1. A sheet obtained by wrapping a water-absorbent pulp carrying an organic water-absorbing agent which absorbs water and is semi-solidified and has an excellent water-absorbing property with a water-permeable cloth having morphological stability, and which is radioactive. A method for treating contaminated water containing a radioactive substance, which comprises absorbing the contaminated water containing a substance and treating the semi-solidified sheet as it is as a radioactive waste.