Melting treatment of incineration ashes of radioactive waste

Ozawa, Tatsuya; Maeda, Toshikatsu; Mizuno, Tsuyoshi; Bamba, Tsunetaka; Nakayama, Shinichi ; Hotta, Katsutoshi*

Melting treatment is a candidate solidification technique for nonflammable low-level radioactive wastes including metals, incineration ashes, and glasses. Simulated incineration ashes of a wide range of chemical compositions were molten at 1,600C to produce lab-scale slag form. No visible pores and separated phases were observed in the slag specimens. It was found by optical observation that some precipitates and small voids were uniformly distributed in many of the specimens. The precipitates were identified to be iron oxides by XRD analysis. The present tests indicate that melting treatment is technically capable to produce stable slag from incineration ashes, which is one of representative TRU-cotaminated radioactive wastes.