Decommissioning considerations for molten salt type reactors

Molten salt type small modular reactors are presently being developed as a future option for providing electricity and alternative energy forms. The current proposed designs do not address the decommissioning and decontamination activities associated with these reactor technologies. This work outlines a means of simulating the decommissioning of a salt-facing and containing reactor component at the end of its service life using a Hastelloy C-276 tube segment which contains previously melted FLiNaK salt. Initial experiments have shown that salts tend to change in condition over time and migrate from one location to another. Experiments performed in this work have examined the migration of the salt and the application of heating and pressure reduction to assist in collecting the salt for removal from the test section. Decommissioning of a molten salt reactor will require a careful approach and the results of this paper will identify some of the concerns that need to be addressed. (author)