Devoluming method and facility for miscellaneous low level radioactive solid waste

Incombustible materials and combustible/less combustible materials are classified, and then subjected to pretreatment of forming them into those having size and shape suitable to melting/oxidation/decomposition respectively. Then, the incombustible materials and combustible/less combustible materials are supplied respectively to two regions of a melting/oxidation/decomposition furnace, the incombustible materials are melted by plasma heating in one of the regions, and the combustible/less combustible materials are oxidized/decomposed on molten materials overflowed to the other region. Residues of oxidation/decomposition are discharged together with molten materials, and solidified by cooling to form waste bodies. According to this method, since the incombustible materials and the combustible/less combustible materials are devolumed at the same time, the devoluming rate as well as the efficiency for the treatment are extremely improved. The less combustible materials which requires high temperature for the oxidation/decomposition are oxidized/decomposed on the molten materials, they can be oxidized/decomposed efficiently, and the residues are melted and integrated with the molten incombustible materials automatically. (T.M.)