RADIOACTIVE DECONTAMINATION METHOD USING METHYLENE CHLORIDE

摘要

A radioactive decontamination method for decontaminating a radioactive-contaminated object by using methylene chloride in place of conventionally used hydrocarbon fluoride or perchloroethylene. The radioactive-contaminated object is impacted by methylene chloride solution. Before the impacting, a preparatory step is executed as required in which radioactive contaminant, which is usually radioactive-contaminated epoxy-resin paint layer on a part used in a nuclear facility, is impregnated with methylene chloride solution so as to swell, thus facilitating exfoliation of the contaminant from the object. The methylene chloride solution is filtered and distilled so as to be decontaminated and subjected to a repeated use for impacting the radioactive-contaminated object. Methylene chloride solution exhibits much greater radioactive decontamination effect than solutions of conventional decontamination mediums such as hydrocarbon fluoride and perchloroethylene and is not so polluting as the known decontamination mediums. The decontamination of methylene chloride itself, which is effected through the distillation, can be executed with much smaller electrical power consumption as compared with the case where perchloroethylene is used.