Thorium-based Fast Reactors: Potential Benefits and Challenges

Use of thorium in Fast Reactors (FR) is gaining consideration in the scientific community thanks to its potential benefits in terms of waste management. The present paper investigates the performance of Th in three FRs: a TRU-burner sodium-cooled FR, an iso- breeder lead-cooled FR and a fast-spectrum Molten Salt Reactor (MSR). The study confirms the relatively low actinide radiotoxicity generated by Th fuel in a closed cycle that could result beneficial to waste management. In addition, notably improved safety parameters are generally observed, which in turn allows increasing the TRU-burning rate while complying with safety requirements. The MSR emerges as the most promising option from the safety features standpoint and thanks to the unique flexibility fostered by a liquid fuel.