On the use of a molten salt fast reactor for transmutation fulfilling the requests of the nuclear phase out decision

The 'Energiewende' in Germany has put some questions on the future of the P&T research. The Bundesministerium für Wirtschaft Energie and the Bundesministerium für Bildung und Forschung have launched a study in 2012 to answer these questions on a broad scientific basis. A major point during the discussions was the so-called last transmuter problem. This requires special attention in the case of the nuclear phase out, since transmutation of transuranium isotopes is only attractive under the phase out condition when this problem can be solved. Recently, a solution has been proposed, the so-called twofold operation cycle using a molten salt fast reactor.
Based on this proposal a simulation for the burning of the 170t TRUs remaining in Germany after the phase out as efficient as possible. A salt configuration based on the MOSART composition is used which is able to carry the required amount of TRUs for the fertile free operation. The requested number of reactors, the required operation time and the expected TRU leftovers are determined. Finally, a general discussion is added which major R&D topics would have to be envisaged for the realization of P&T in a molten salt fast reactor.