Evaluation of platinum alloy melters for vitrification of radioactive wastes

A bushing melter constructed of platinum-rhodium is being evaluated for vitrification of special high gamma radioactive wastes for long-term recoverable storage. The basic design parallels that used in the fiberglass industry. Nonradioactive chemical surrogate wastes have been used in the process work. The simulant wastes and glass frit are fed separately to the melter and mixed within the liquefied mass. Several different frits have been used, and temperatures have been varied to assess the effects on the quality of the product glasses. Melt temperatures >1500{degrees}C are typical, and significant effects on the material of construction are evident. Analyses of the Pt-Rh materials have been used to emphasize the need to set limits in the operating parameters to avoid unacceptable changes in properties of the bushing as a container.