Development of a melter system for actinide vitrification. Revision 1

摘要

The stabilization of actinides in glass was a technology considered for repository disposal of weapons-grade plutonium. Accelerated development efforts of a suitable glass composition (lanthanide borosilicate; LaBS) and melter system were completed in 1997. The other form involved in the down-selection process was a crystalline ceramic based on Synroc. As part of the glass development program, melter design activities and component testing were completed to demonstrate the feasibility of using glass as an immobilization medium. A prototypical melter was designed and built in 1997. The melter system centered on a Pt/Rh-alloy melter vessel and drain tube that were heated by two separate induction systems. An optional Pt/Rh stirrer was incorporated into the design to facilitate homogenization of the melt. Integrated powder feeding and off-gas systems completed the overall design. Concurrent with the design efforts, testing was conducted using a plutonium surrogate LaBS composition in an existing (near-scale) induction melter to demonstrate the feasibility of processing the LaBS glass on a production scale. Additionally, the drain tube configuration was successfully tested using a plutonium surrogate LaBS glass. The down-selection resulted in the selection of the ceramic option for future development. The successful testing of the induction melter system, however, showed that it is a viable technology for actinide vitrification. Currently, the melter system, complete with control and offgas components, is being successfully utilized to support the Americium/Curium vitrification program at the Savannah River Site.