Method of dismantling and withdrawing of activated concrete for reactor

Purpose: To establish the flame cutting technique in the activated concrete cutting process keeping the environment free from contamination. Method: A flame cutter is inserted into water inside the reactor cavity to be dismantled. By using the flame cutter, the activated concrete on the inner surface of the cavity is melted down to some proper sizes of blocks from top to bottom. Then, the concrete blocks are lifted and moved out of the cavity by using a conveyor. For less recontamination of the concrete, the water level inside the cavity is lowered in the dismantling process so that the flame cutter is not disposed over the water surface. Radioactive fumes or dusts produced in the cutting process are trapped in water without giving any bad influence to the environment. (Ikeda, J.)