Development of noble metals-compatible vitrification melter in Tokai Vitrification Facility

Kobayashi, Hidekazu ; Kodaka, Akira; Iwabuchi, Hiroki

In JAEA's Tokai Vitrification Facility (TVF) at Tokai Reprocessing Plant (TRP) site, high level liquid waste (HLLW) generated from reprocessing of spent fuels is vitrified with a liquid-fed joule-heated ceramic melter (LFCM). As noble metals (NMs) in HLLW aren't soluble to the glass, and have low resistivity and higher density, they deposit on bottom of melter and form electrical path and thus disturb melter operation. The first and second TVF melter have square pyramidal shaped bottom and issue that NMs on the bottom are difficult to drain out and have to be removed periodically. To solve this issue, we are developing the third melter with conical shaped bottom. The effect of changing the bottom structure was confirmed by thermo-fluid analysis code. Structural optimization of strainer in the upper part of drain nozzle was carried out by visualization experiment. In this meeting, activity of third melter development including past melter structure will be introduced.