KR100679562B1 - A removal of radioactive contaminant - Google Patents

Abstract

A remover of radioactive contaminant is provided to obtain a high decontamination by mixing a metal complexing agent, a chelate compound, a surfactant, and a reattachment prevention agent. A remover of radioactive contaminant is composed of a metal complexing agent of 5 to 15% absorbing a metal oxide(Mn-54, Fe-59, Co-58, Co-60, Cs-137, Sr-90) which is the origin of the radioactive contamination, a chelate compound of 0.005 to 5%, a surfactant of 2 to 7% separating a contaminant from a surface, a reattachment prevention agent of 3 to 5% preventing the separated contaminant from being reattached to the surface, and the water.

Description

A removal of radioactive contaminant

1 is a radioactive pollutant remover of the present invention (decontamination agent for AT wet equipment)

Dilution stability test report

Figure 2 is a radioactive pollutant remover of the present invention (decontamination agent LA protective clothing)

Dilution stability test report

The present invention relates to a radioactive pollutant remover, which will be described in more detail, in which companies that use radioisotopes such as nuclear power plants, non-destructive facilities, or hospitals are contaminated with radioactive materials as well as various facilities or air holes, Metal oxides (Mn-54, Fe-59, Co-58, Co-60, Cs-137, Sr-90, etc.), which are the sources of contamination, are adsorbed using metal complex salt forming agents and chelate compounds, and surfactants To remove the contaminants from the surface by using, and to remove the radioactive contaminants using a reattachment prevention agent in order to prevent the detached radioactive material is attached to the surface again, to increase the activity of the metal complex salt forming agent used at this time Radioactive contaminants used to remove radioactive contaminants characterized by the addition of oxidizing agents, acids, alkalis, chelating agents It relates to scavengers.

Decontamination of radioactive pollutants relates to radioactive decontamination agents that are used to cleanly remove radioactive material from unwanted places. Companies that use radioactive isotopes such as nuclear power plants, non-destructive facilities, or hospitals are contaminated with radioactive materials as well as various facilities, air wards, and work clothes. Therefore, the defense and removal of pollution is an important issue for safety management in handling companies.

The main causes of radioactive contaminants are nuclear fuel materials and compounds thereof, and the radioactive contamination is contaminated with facilities, equipment, devices, work clothes, and the body by handling these substances in various radioisotope use facilities. Such contaminated radioactive material should be removed, and decontamination is very important for facility management area decontamination, use facility and facility equipment decontamination, work cloning salt and skin decontamination. Decontamination must be done directly, and the use facilities or equipments can cause enormous economic loss if they are not decontaminated below the allowable standard. Therefore, the economic value of decontamination and the cost of decontamination should be considered first.

There are various methods for removing such radioactive contamination, depending on the pollutants. Generally, deposition, cleaning, polishing, etc. are performed. Electrodecontamination method, ultrasonic method, jet clean method, sand There is also a method of using a special device such as the blast method. Decontamination agents are chosen depending on how they bind to radioactive contaminants.

In other words, as a method for decontaminating physical surface contamination, organic acid mixtures, chelating agents, synthetic detergents, and the like are used as methods for treating surfaces using equipment and decontamination agents for chemical surface contamination. Conventionally, its use has been classified according to the object as a decontamination agent. Generally, commercially available soaps are used as they are or in addition to organic acids, caustic soda, acetone, carium bichromate, titanium oxide, sodium bicarbonate, and alginate. Oda bare etc. have been used alone or in combination.

However, in order to prevent contamination of the body by radioactive isotopes, the pollutant works mainly use the wet decontamination method. Conventional chemicals used for the purpose of decontamination of radioactive materials have a defect that usually has a selective effect depending on the pollutant, and has a defect that is not widely used, and also because its action is a simple physical and mechanical decontamination. Only if the work is repeated several times, it can be decontaminated within some allowable limits and the effect is not perfect. As a result, the wastes are increased nationally and economically by treating the equipment or equipment that has not been completely decontaminated as radioactive waste. gave.

The present invention is provided to more efficiently solve the problems of the prior art as described above, the metal oxide (Mn-54, Fe-59, Co-58, Co-60, Cs-137, which is the source of radioactive contamination) Sr-90, etc.) are adsorbed using a metal complex salt forming agent and a chelating compound, and a surfactant is used to remove contaminants from the surface, and a reattachment preventing agent is used to prevent the detached radioactive material from sticking to the surface again. To remove the contaminants, in order to increase the activity of the metal complex salt forming agent is used to remove the radioactive pollutant used to remove the radioactive pollutant, characterized in that the addition of an oxidizing agent, acid, alkaline, chelating agent. In addition, the present invention does not affect the filtration evaporation concentration method, ion exchange resin method, which is a method according to Article 110 of the Enforcement Decree of the Atomic Energy Act. In addition, the concentrated radioactive material did not cause other reactions in the waste treatment process (concrete, superparaffin solidification), and it was experimentally found that the solidified radioactive waste did not diffuse and leak. By this, it becomes a solid dry matter and incineration is possible if necessary. In this case, it is intended to provide a radioactive pollutant remover that does not generate toxic gases and emitted radiation.

The present invention relates to a radioactive pollutant remover, which will be described in more detail, in which companies that use radioisotopes such as nuclear power plants, non-destructive facilities, or hospitals are contaminated with radioactive materials as well as various facilities or air holes, Metal oxides (Mn-54, Fe-59, Co-58, Co-60, Cs-137, Sr-90, etc.), which are the sources of contamination, are adsorbed using metal complex salt forming agents and chelate compounds, and surfactants To remove the contaminants from the surface by using, and to remove the radioactive contaminants using a reattachment prevention agent in order to prevent the detached radioactive material is attached to the surface again, to increase the activity of the metal complex salt forming agent used Radioactive contaminants used to remove radioactive contaminants characterized by the addition of oxidizing agents, acids, alkalis, chelating agents It relates to scavengers.

Hereinafter, the present invention will be described in detail with reference to the results and examples shown in the drawings.
[Manufacture of radioactive pollutant remover]
The radioactive contaminant remover of the present invention is a metal complex salt former to adsorb metal oxides (Mn-54, Fe-59, Co-58, Co-60, Cs-137, Sr-90, etc.) which are the sources of radioactive contamination. 5-15%, 0.005-5% chelating compound, 2-7% surfactant to remove contaminants from the surface, 3-5% anti-reposition agent to prevent the detached radioactive material from sticking back to the surface It is composed of a radioactive pollutant remover composed of water, and in detail, the metal complex salt forming agent is formed by adding an oxidizing agent, an acid, an alkali, a chelate forming agent to increase the activity, and the chelate compound is made of a metal such as stainless steel or steel. The radioactive contaminants adhering to the surface are the forming agents of acid and alkali chelate compounds, and the radioactive contaminants adhering to the work clothes (protective coating) are the forming agents of alkaline chelate compounds. A and surfactant polyoxyl ethylene octylphenyl rate (polyoxy ethlene octyl phenylether) of the re-adhesion preventing agent is characterized been prepared wherein the non-ionic surface-active derivatives (Nonion surfactant derivative compounds).

Example 1 Comparative Test of Radioactive Material Decontamination Agent (AT), Synthetic Detergent, and Organic Acid Mixture

 1. Test subject and measuring equipment

 This experiment was conducted to confirm the decontamination factor of the radioactive decontamination agent and the effect of the decontamination agent and to confirm the satisfaction of practical use. First, the place used for the experiment was conducted on the bottom of the drum reservoir and the pump sealing surface contaminated with radioactivity. The decontamination method was used as a decontamination tool, and the decontamination method was obtained by applying the decontamination agent to the decontamination paper and rubbing the decontamination 40 times to obtain an average value. The equipment for measuring the decontamination performance is shown in Table 1. Same as

2. Test method

The decontamination agents used in the test were classified into four concentration differences (5%, 10%, 20%, and 50%) of the radioactive material decontamination agent (AT), synthetic detergent, and organic acid mixture. Synthetic detergent, organic acid mixture, and radioactive decontamination agent (AT) were carried out using decontamination paper, which is a decontamination tool.The decontamination method was performed by soaking decontamination agents in the decontamination paper and rubbing for 40 times. The method was performed twice, and the average value was obtained, and the decontamination effects of the synthetic detergent, the organic acid mixture, and the decontamination agent (AT) were compared.

3. Test procedure

end. Decontamination Control

1) Radioactive decontamination agent (AT)

Radioactive decontamination agent (AT) was prepared by dividing the four different concentrations are shown in Table 2.

I. Selection of test object

First, four places with high pollution of the waste disposal building drum storage were selected as the contaminated floor and tested by concentration using the adjusted decontamination agent.

The pump sealing surface (PUMP SEAL) was used to classify the pump sealing surface of the waste treatment building into four and tested by concentration using the decontamination agent adjusted.

All. Decontamination method of contaminated site

Determine the bottom of the contaminated drum reservoir and 4 pump seals and rub each decontamination solution into the decontamination paper and rub it 40 times.Then select another 4 places so that the decontamination solution is sufficiently buried. Decontamination was carried out 40 times.

la. Pollution degree measuring method

Measure the contamination level on the sample before decontamination, rub the decontaminated floor, the contaminated pump and the sealing surface area 4 to 5 times with decontamination paper after decontamination, wipe off the decontamination solution, and rub the decontamination paper 10 times over 100 cm2 area. Surface contamination was measured.

4. Experimental Results

1) pump On the sealing surface Decontamination  Decontamination coefficient measured using

First, four pump sealing surfaces with high levels of radioactive contamination were selected, and each of the decontaminants (AT), synthetic detergents and organic acid mixtures having concentration differences of 5%, 10%, 20%, and 50% in the decontamination paper was selected. The decontamination was carried out with the decontamination solution, and the results are shown in the measurements shown in Tables 3, 4, and 5.

As shown in Table 3, the decontamination coefficient was measured according to the concentration difference (5%, 10%, 20%, 50%) of the decontamination agent (AT) solution, and the decontamination agent (AT) was measured using the decontamination paper. As an average value of the decontamination coefficient of one pump sealing surface, the decontamination coefficient of 13.74 kbq / m <2> was shown.

As shown in Table 4, the decontamination coefficient was measured according to the concentration difference (5%, 10%, 20%, 50%) of the removal solution using the synthetic detergent, and the pump sealing surface measured using the synthetic detergent in the decontamination paper. The decontamination coefficient averaged was 11.34 kbq / m 2.

As shown in Table 5, the measured values of the decontamination coefficient according to the concentration difference (5, 10, 20, 50%) of the removal solution were shown. As the average value of the decontamination coefficient of the pump sealing surface measured using the organic acid mixed solution in the decontamination paper, A decontamination factor of 11.42 kbq / m 2 was shown.

2) at the drum cellar bottom Decontamination  Decontamination coefficient measured using

First, four waste disposal building drum storage areas with high levels of radioactive contamination were selected and each decontamination agent (AT), synthetic detergent, having a concentration difference of 5%, 10%, 20%, and 50% in the decontamination site. Decontamination was performed with the decontamination liquid of the organic acid mixture.

As shown in Table 6, it shows the decontamination coefficient of the bottom of the drum (DRUM) according to the concentration difference (5, 10, 20, 50%) of the removal liquid, the drum measured using the decontamination agent (AT) in the decontamination paper The mean value of the decontamination coefficient at the bottom of the cellar showed a decontamination coefficient of 23.19 kbq / m 2.

As shown in Table 7, the decontamination coefficient measured at the bottom of the drum reservoir according to the difference in concentration (5, 10, 20, 50%) of the removal liquid, and the bottom of the drum reservoir measured using the detergent The average value of the decontamination coefficient was 5.22 kbq / m 2.

As shown in Table 8, it shows the decontamination coefficient at the bottom of the drum reservoir according to the concentration difference (5, 10, 20, 50%) of the removal liquid. As the average value of the decontamination coefficient, the decontamination coefficient of 4.75 kbq / m 2 was shown.

Table 9 summarizes the average decontamination coefficients measured using decontamination agents (AT), synthetic detergents, and various decontamination agents of organic acid mixtures on the pump sealing surface and drum storage floor contaminated with radioactive contaminants. Same as

As a result, as shown in Table 9, the decontamination factor (AT) 13.74, the synthetic detergent 11.34, and the organic acid mixture 11.42 were shown in the decontamination coefficient indicating the degree of decontamination of the radioactive substance, and the decontamination agent (AT) was found to The results showed excellent results even on the smooth surface of the contaminants, and the decontamination coefficient at the bottom of the coarse drum reservoir was shown as a removal agent (AT) 23.19, a synthetic detergent 5.01, and an organic acid mixture 4.75. It can be seen that AT) is excellent in decontamination, summarized in Table 10.

In addition, as shown in Table 10, the decontamination power of the smooth metal surface is the decontamination coefficient of the decontamination agent (AT), synthetic detergent, organic acid mixture is 13.74kbq / ㎡, 11.34kbq / ㎡, 11.42kbq / ㎡, respectively Excellent results were obtained for contaminants with smooth surfaces, such as sealing surfaces, and the decontamination effect of rough surfaces such as the bottom of rough drum reservoirs showed a very good result with decontamination agent (AT) of 23.19 kbq / m2. Detergents and organic acid mixtures were not suitable for decontamination on floors or rough areas.

Example 2 Comparative Test with Radioactive Material Decontamination Agent (LA) and Laundry Detergent

1. Average by detergent when washing directly in the washing machine Decontamination rate

Comparative tests with radioactive decontaminants (LA) and laundry detergents,

The test subjects were 38 working clothes of contaminated protective clothing.The decontamination method was to put the detergent directly into the washing machine and wash it for 60 minutes, and to compare the degree of removal of radioactive material contamination between decontamination agent (AL) and synthetic detergent. It is shown in Table 11.

As shown in Table 11, the average decontamination rate of the protective clothing when washing directly in the washing machine using the decontamination agent (LA), the average decontamination rate was 64.98%.

As shown in Table 12, the average decontamination rate of the protective clothing when washed directly in the washing machine using a synthetic detergent, the average decontamination rate was 22.27%,

As shown in Table 11 and Table 12, when washing protective clothing contaminated with radioactive material directly in a washing machine, the result of the average decontamination rate of the protective clothing is 64.98% decontamination rate of the anti-fog remover (LA) of the present invention, general Synthetic detergents showed a decontamination rate of 22.27%, indicating that the antifogicide (LA) had a very high decontamination rate (64.98%).

2. Soak the laundry and wash it after a certain time. Decontamination rate

Comparative tests with radioactive decontaminant (LA) and laundry detergents were shown. The test subjects were 10 working clothes of contaminated protective clothing, and the decontamination method was to dissolve the detergent in a large container (water: detergent = 8: 1). After soaking the laundry (protective clothing) for 24 hours, the laundry was washed, and the experiment was performed by comparing the degree of removal of radioactive material contamination between the protective clothing decontamination agent (AL) and the synthetic detergent.

As shown in Table 13, when washed after 24 hours immersed in a protective clothing decontamination agent (LA), the average decontamination rate of the protective clothing was 80.36%, showing a very good decontamination rate.

As shown in Table 14, the average decontamination rate of the protective clothing when washing after soaking with synthetic detergent for 24 hours, the average decontamination rate was 31.57%.

As shown in Table 13 and Table 14, the protective clothing contaminated with radioactive material was dissolved in a large container with detergent (water: detergent = 8: 1), soaked for 24 hours, and then washed. The protective clothing remover (LA) of the invention showed a decontamination rate of 80.36%, and the general synthetic detergents showed a decontamination rate of 31.57%, indicating that the protective clothing remover (LA) had a very high decontamination rate.

In comparative tests with radioactive decontaminants (LA) and laundry detergents, the average decontamination rate for each detergent when washed directly in the washing machine and the laundry after soaking the laundry in a detergent for a certain period of time were compared. When washing clothes directly in the washing machine without immersing the protective clothing, the detergent that shows the best decontamination rate was the decontamination agent (LA) (decontamination rate: 64.98%), and washing the contaminated protective clothing in the decontamination agent for a certain time and washing it directly in the washing machine Decontamination rate was much better than washing, and detergent (LA) (decontamination rate: 80.36%) was the best. Therefore, the longer the immersed contaminated protective clothing in the detergent dilution, the better the decontamination rate, but it was better to wash after 24 hours soaking.

From the above experimental results, it can be seen that the radioactive decontamination agent (AT, LA) of the present invention is superior to a contaminant having a smooth surface, such as a sealing surface, than a synthetic detergent or an organic acid mixture, and has excellent decontamination power on a rough bottom surface. Could.

Therefore, the decontamination of radioactive contaminants attached to metal surfaces such as stainless steel and steel is more effective in decontamination using acid and alkaline chelating compounds. It was easily decontaminated depending on the concentration of the surfactant.

As described above, the present invention, which is made of a metal complex salt forming agent, a chelating compound, a surfactant, and a reattachment preventing agent, has a superior decontamination ability than a conventional decontamination agent and depends on a form of a method of use according to a radioactive contamination object (predetermined schedule After soaking in the container, the result showed that the radioactive decontamination effect was very large, which is very useful industrially and economically.

As described above, although the present invention has been described with reference to the above embodiments, it is not necessarily limited thereto, and various modifications can be made without departing from the scope and spirit of the present invention.

As described through the above examples, the developed product is superior in the contaminants having a smooth surface like the sealing surface than the synthetic detergent or the organic acid mixture, and it can be seen that the decontamination power is excellent in the rough bottom surface, and the metal such as stainless steel and steel The decontamination of radioactive contaminants attached to the surface using acid and alkaline chelating compounds is more effective in decontamination, and the decontamination of working clothes is easier depending on the concentration of use and the concentration of alkaline chelating compound surfactants. Was decontaminated.

Therefore, the radiocontaminant remover made by blending the metal complexing agent, chelating compound, surfactant, and anti-adhesion agent according to the present invention has superior decontamination ability than the conventional decontamination agent and forms of use method according to the radiocontamination object. According to the results (pre-soaked in a certain container), the result is that radioactive decontamination is more effective, which is very useful industrially and economically.

Claims (6)

In radioactive contaminants, metal complex salt formers for adsorbing metal oxides (Mn-54, Fe-59, Co-58, Co-60, Cs-137, Sr-90, etc.) that are the source of radioactive contamination. -15%, chelating compound 0.005 ~ 5%, surfactant 2 ~ 7% to remove contaminants from the surface, 3 ~ 5% anti-reposition agent to prevent the detached radioactive material from sticking back to the surface, the rest is water A radioactive contaminant remover, characterized in that configured as. The radioactive contaminant remover according to claim 1, wherein the metal complex salt forming agent is formed by adding an oxidizing agent, an acid, an alkali, a chelate forming agent to increase the activity value. The method of claim 1, wherein the chelate compound is a radioactive contaminant attached to a metal surface such as stainless steel or steel is an acid, an alkali forming agent of a chelate compound, and in the case of a radioactive contaminant adhered to a work clothes (protective coating). A radioactive pollutant remover, characterized in that the forming agent of the chelate compound. The radioactive pollutant remover of claim 1 wherein the surfactant is polyoxy ethlene octyl phenylether. The radioactive pollutant remover of claim 1 wherein the anti-reposition agent is a nonionic surfactant derivative compounds. The radioactive contaminant remover according to claim 1, wherein the radioactive contaminant remover is used to decontaminate radioactive substances in various equipment, equipment (for wet equipment), and work clothes (protective coating).

Images