ACTIVATION CHARACTERISTICS AND WASTE MANAGEMENT OPTIONS FOR SOME CANDIDATE TRITIUM BREEDERS

Activation and transmutation characteristics are calculated for the candidate breeder compositions Li2O, LiAlO2, Li2SiO3, Li2ZrO3, LiVO3 and 17Li-83Pb. Irradiation conditions comprise a 2.5 y continuous exposure to the neutron flux appropriate to the outboard blanket zone of the EEF reference reactor with an assumed first wall neutron loading of 5 MW m-2. Results are presented for specific activity, surface gamma-dose rate, ingestion and inhalation doses and compositional changes. neglecting any retained tritium, activity is least for Li2O and LiVO3 and greatest for Li2ZrO3 and 17Li-83Pb. The silicate and aluminate are intermediate in level. Following reactor service, all the materials should be suitable, after appropriate conditioning, for geological disposal as Intermediate Level Waste. Alternatively, they could be considered for recycling to reclaim the unused lithium. In all cases, recycling is probably feasible within 10 y of removal from service and should be easier for the oxide, silicate and vanadate.