Tritium release from the various solid breeder materials irradiated in exotic experiments 1, 2 and 3

Abstract

In-situ tritium release experiments have been performed on LiAlO b2, Li 2O, Li 2ZrO 3 and Li 2SiO 3 in the High Flux Reactor (HFR) at Petten. The experimental programme, EXOTIC, fits in the European Fusion Technology Programme on Blanket Technology and is jointly carried out by SNL-Springfields, SCK/CEN — Mol and ECN — Petten in cooperation with JRC — Petten. The vented capsules are purged with helium-0.1 vol% H 2. The main parameters were material density (75–95% TD), temperature (400–650°C), 6Li content, and irradiation time. During the steady state irradiation of EXOTIC-3 some temperature transients were carried out. They caused an immediate and strong effect on the release of tritium. More or less time was needed to restore steady-state tritium release. Almost complete tritium release was observed for: LiAlO 2 at 440°C, Li 2SiO 3 at 550°C, Li 2O at 600°C and Li 2ZrO 3 at 650°C for material densities of 75–80% TD. For 95% TD Li 2SiO 3 the fractional tritium release was < 70% at 630°C.