低レベル放射性試料の焼却実験システムの設置と燃焼実験

Setting up Experimental Incineration System for Low-level Radioactive Samples and Combustion Experiments. Yasuhiro YUMOTO, Tadashi HANAFUSA, Tomohiro NAGAMATSU and Shigeru OKADA: Radioisotope Center, Okayama University, 2-5-1, Shikata-cho, Okayama-shi 700, Japan.
An incineration system was constructed which were composed of a combustion furnace (AP-150 R), a cyclone dust collector, radioisotope trapping and measurement apparatus and a radioisotope storage room built in the first basement of the Radioisotope Center.
Low level radioactive samples (LLRS) used for the combustion experiment were composed of combustible material or semi-combustible material containing 500 kBq of 99mTcO4 or 23.25 kBq of 131INa. The distribution of radioisotopes both in the inside and outside of combustion furnace were estimated. We measured radioactivity of a smoke duct gas in terminal exit of the exhaust port. In case of combustion of LLRS containing 99mTcO4 or 131INa, concentration of radioisotopes at the exhaust port showed less than legal concentration limit of these radioisotopes. In cases of combustion of LLRS containing 99mTcO4 or 131INa, decontamination factors of the incineration system were 120 and 1.1, respectively.