Incineration tests for the combustible TRU wastes

Since various kinds of plutonium-contaminated (TRU) wastes have been arising at the MOX fuel fabrication facilities, a CECE (Carbonisation Enterprise et Ceramique Enterprise) type incinerator to burn the combustible TRU wastes was installed at the Plutonium Fuel Division. Subsequently to the preliminary non-radioactive and uranium tests, the actual hot tests were carried out using plutonium. The incinerator with design capacity of 20 kg/hr is composed mainly of a combustion chamber, high temperature filter, diluter, HEPA filter and scrubber. The sham wastes containing carton boxes, paper sheets, rags, polyethylene and plywoods in various proportions were prepared, and plutonium nitrate or oxide was added to the sham wastes. The sham wastes were fed to the primary combustion chamber at the rate of 1 kg for every three minutes. From the experimental results, it was concluded that 1) the overall decontamination factor of the incinerator was about 5 x 109, and the incinerator of this type is suitable for incinerating the actual combustible TRU wastes, 2) the design capacity of 20 kg/hr was attainable in the case of actual wastes, 3) plutonium was confined satisfactorily in the incinerator, and 4) the techniques for the operation and maintenance were established. (Yoshitake, I.)