Shigeru Mihara

Development of Induction Melting System With Active Insulator for Radioactive Solid Waste

The melting treatment is suitable for reducing the volume of the wastes because of the high volume reduction ratio (the volume reduction ratio is the initial volume to the volume after treatment). We have developed a new high-frequency induction melting system for the low-level radioactive miscellaneous solid wastes. The non-conductive ceramic canister and a heat loss compensator (Active insulator) were used in this new system. It is difficult to melt a large amount of the non-metallic materials with the canister. We solved this problem by using the active insulator, which was made of the conductive material. Melting performance confirmation tests were performed in the medium-scale melting system. Based on the result of the medium-scale melting test and multi-dimensional thermal-hydraulic analysis, the full-scale melting system was designed and constructed. We performed the melting tests using the full-scale melting system. the volume ratio of the non-metallic wastes at the re-solidification was more than 70%. Behavior of nuclides was also investigated with non-radioactive Co and Cs tracers. The residual ratio of Co and Cs were 97%, 58%, respectively.Copyright