Development of laser decontamination; Research and fundamental experiment

Fukui, Yasutaka ; not registered; Tanimoto, Kenichi; Terunuma, Seiichi

As the material is irradiated by laser beam, its surface is instataneously heated and ablation. the contaminant in surface layer of radioactive wastes will be decontaminated, provided that such the physical phenomenon is used of decontamination technique. The applicability with decommissioning of laser decontamination technique are investigated by the research of the associated laser techniques and the removing test with metal surface. The results of the research and the test is as follows. (1)The research of laser decontamination. On the YAG and the eximer laser beam, there were some study reports of the decontamination, with the metal and the concrete. The structural material. the biological shield, and the waste strage vessel, these objects were regarded as the objects of the laser decontamination. (2)The removing test of the metal surfacc by lascr beam. The removing performance was examined by irradiating line forcused YAG laser beam with the stainless steel surface. The average removal depth rose, in proportion the product of the energy beam density and the number of beam pulse in He atomosphere. The removal depth was obtained more than 1m, in condition of the laser beam energy was 400mJ and the moving velocity of the test piece was 0.25mm/sec. About 65% of the ablation products were collected, by the simple absorbing system of the open type. (3)Future plan. It is necessary, Examining the removing performance and the variable property of the removal surface, investigating the decontamination technique of the large area and the collecting technique of the ablation products, and so. Thereafter the application to the decontamination will be studied.