Thermal Enhancement Cartridge Heater Modified (Tech Mod) Tritium Hydride Bed Development Part I – Design and Fabrication

The Savannah River Site (SRS) tritium facilities have used 1^st generation (Gen1) LaNi _4.25 Al _0.75 (LANA0.75)  metal hydride storage beds for tritium absorption, storage, and desorption.  The Gen1 design utilizes hot and cold nitrogen supplies to thermally cycle these beds.  Second and 3^rd generation (Gen2 and Gen3) storage bed designs include heat conducting foam and divider plates to spatially fix the hydride within the bed.  For thermal cycling, the Gen2 and Gen 3 beds utilize internal electric heaters and glovebox atmosphere flow over the bed inside the bed external jacket for cooling. The currently installed Gen1 beds require replacement due to tritium aging effects on the LANA0.75 material, and cannot be replaced with Gen2 or Gen3 beds due to different designs of these beds.  At the end of service life, Gen1 bed desorption efficiencies are limited by the upper temperature of hot nitrogen supply.  To increase end-of-life desorption efficiency, the Gen1 bed design was modified, and a Thermal Enhancement Cartridge Heater Modified (TECH Mod) bed  was developed.  Internal electric cartridge heaters in the new design to improve end-of-life desorption, and also permit in-bed tritium accountability (IBA) calibration measurements to be made without the use of process tritium.  Additional enhancements implemented into the TECH Mod design are also discussed.