Tritium Balance in High‐Temperature Gas‐Cooled Reactors

Abstract

In high‐temperature gas‐cooled reactors, tritium produced by fission is, for the most part, retained in the coated particle fuel, but 3 He‐ and 6 Li‐originated tritium takes part in a complex system of sorption, diffusion, and exchange reactions in the core graphite. Permeation through the heat‐exchanger tube walls leads to secondary circuit contamination. It was found that tritium is very soluble in graphite and that permeation is significantly reduced by oxide layers on metal surfaces.