Molten Salt Reactors

Abstract — Nuclear power is advancing slowly because of public concerns about nuclear accidents, radioactive waste, fuel supply, cost, and nuclear proliferation. The development of molten salt reactors could alleviate most of these concerns and prevent water-cooled reactor accidents like those at Three Mile Island, Chernobyl, and Fukushima. The purpose of this article is to provide information about the potential advantages and problems of molten salt reactors. The coolants could be either fluorides or chlorides , operated above their melting temperatures, to avoid solidification, and well below their boiling temperatures, to prevent evaporation losses. “Fast” reactors use energetic fission neutrons, while “thermal” reactors use graphite to slow the neutrons down to thermal energies. We describe four reactor types: solid fuel thermal, liquid fuel thermal, liquid fuel fast, and “stable salt” fast reactors (liquid fuel in tubes). We discuss load following, reactor design projects, and development problems. Liquid fuel reactors will require a chemical processing plant to adjust fissile fuel inventory, fission products, actinides, and corrosivity in a hot, highly-radioactive environment.