Chemical partitioning technologies for an ATW system

A roadmap for the development of the technology of an Accelerator Transmuta tion of Waste (ATW) system was recently submitted to the U.S. Congress by t he U.S. Department of Energy. One element of this roadmap was a development plan for the separations technologies that would be required to support an ATW system operating with a sustained feed of 1,450 tonnes of commercial l ight water reactor spent fuel per year. A Technical Working Group was const ituted to identify appropriate separations processes and prepare a plan for their development. The baseline process selected combines aqueous and pyro chemical processes to enable efficient separation of uranium, technetium, i odine, and the transuranic elements from LWR spent fuel in the head-end ste p. For the recycle of unburned transuranics and newly-generated technetium and iodine from irradiated ATW transmuter assemblies, which were given to b e metallic in form, a second and quite different pyrochemical process was i dentified. The diversity of processing methods was chosen for both technica l and economic factors; aqueous methods are deemed to be better suited to l arge tonnages of commercial oxide spent fuel, while it is considered that p yrochemical processes can be exploited effectively in smaller-scale operati ons, particularly when the application is to metallic fuels or targets. A s ix-year technology evaluation and development program is foreseen, by the e nd of which an informed decision can be made on proceeding with demonstrati on of the ATW system. (C) 2001 Published by Elsevier Science Ltd. All right s reserved.