Tritium Control and Capture in Salt-Cooled Fission and Fusion Reactors

Three advanced power systems use liquid salt coolants that generate tritium and thus face common challenges to prevent release of the tritium to the environment. The Fluoride-salt-cooled High-temperature Reactor (FHR) uses the same graphite-matrix coated-particle fuel as High-Temperature Gas-cooled Reactors (HTGRs) and clean fluoride salt coolants. Molten salt reactors (MSRs) dissolve the fuel in a fluoride or chloride salt and release the fission product tritium to the salt. High-magnetic-field fusion machines may use liquid salt cooling and blankets because of the very high power densities of this new class of fusion machine. The three technologies can be coupled to a Nuclear Air-Brayton Combined Cycle (NACC) enabling variable electricity with base-load reactor operation. Converging requirements for tritium control in 700 degrees C liquid salts are leading to cooperative programs across technologies; tritium models that combined generation, chemistry, metal corrosion and transport; and new tritium control technologies using advanced carbon forms, metals produced by additive manufacturing and other technologies.