A pilot plant of continuous bituminization process for solidifying radioactive wastes

A pilot plant comprised of a vertical thin film LUWA evaporator as a principal bituminization unit having an evaporating capacity of 50 kg/h has been installed at Haneda Factory of out company. The process of bituminization is based on a technical licence agreement with the SGN introducing the technology and the outcomes from the R D by the French CEA. The ''vertical type'' bituminization plant has excellent performances in solidifying radioactive liquid wastes arising at nuclear power plants. Construction contracts of treating plant of this type of process at three nuclear power stations have already been awarded to our company, and one of them is nearing the stage of test operation. Meanwhile, our pilot plant of one fourth of the actual plant in capacity has well proved the designed functioning of the equipment to yield satisfactory bituminized products. The applicability of domestic bitumen of different grades as well as the effectiveness of selected surfactants have been tested with simulated liquid waste concentrates of different kinds, spent resins, and incinerator ashes. The findings obtained over past 10 months are now serving for establishing the operational guides for the actual plant at each nuclear power station. (auth.)