(350g) Initial Production of Full-Scale Ceramic Waste Forms for the EBR-II Spent Fuel Treatment Process

The Experimental Breeder Reactor-II (EBR-II) was a fast neutron spectrum test reactor that operated at Argonne National Laboratory-West (now Idaho National Laboratory) from 1963 until 1994. It employed sodium-bonded, metallic U-Zr fuel with a total heavy metal inventory at shutdown of approximately 25 metric tons. From 1996 to 1999, ANL successfully demonstrated at engineering-scale a pyrochemical process for treating the spent fuel that stabilized the sodium, recovered pure U metal, and generated durable high-level waste forms for the fission products, plutonium, and minor actinides. Since 1999, research and development has continued on the process to improve separation efficiency, lower operating cost, and develop advanced technologies to increase the functionality of the spent fuel treatment process. The process for disposing of waste salt from the electrorefiners is referred to as the ceramic waste process and has been scaled-up to achieve production operation capacity demands. The process includes zeolite size reduction, zeolite drying, salt/zeolite blending, and high temperature consolidation. Full-scale equipment has been installed in non-radiological laboratories at Idaho National Laboratory to initially make non-radioactive, full-scale waste forms to confirm the suitability of equipment design and to select operating parameters. In full-scale batches, zeolite-4A has been successfully dried to less than 0.5 wt% water. Also at this scale, salt has been very efficiently absorbed into the dried zeolite. Using the resulting salt-loaded zeolite, ceramic waste forms in excess of 300 kg have been made. From the initial lab-scale experiments, the waste form and the process by which it has been made has been scaled-up by a factor of 1500. The next step for process development is qualification of the process via repeatability runs to establish that given operating parameters will reliably produce identical results time after time. Once the process qualification is complete, final equipment installations will be completed in the hot cells, and production operations for the ceramic waste process with waste salt from the electrorefiners will commence.