From MYRRHA to XT-ADS:Development of Pb-Bi cooled ADS as a fast spectrum irradiation facility in Europe

摘要

The MYRRHA project started in 1998 by SCK·CEN in collaboration with Ion Beam Applications (IBA, Louvain-la-Neuve), as an upgrade of the ADONIS project. MYRRHA is designed as a multi-purpose irradiation facility in order to support research programmes on fission and fusion reactor structural materials and nuclear fuel development. Applications of these are found in ADS systems and in present generation as well as in next generation critical reactors. The first objective of MYRRHA however, will be to demonstrate on one hand the ADS concept at a reasonable power level and on the other hand the technological feasibility of transmutation of Minor Actinides (MA) and Long-Lived Fission Products (LLFP) arising from the reprocessing of radioactive waste. MYRRHA will also help the development of the Pb-alloys technology needed for the LFR (Lead Fast Reactor) Gen.IV concept. Transmutation of MA can be completed in an efficient way in fast neutron spectrum facilities. Both critical reactors and sub-critical Accelerator Driven Systems (ADS) are potential candidates as dedicated transmutation systems. However, critical reactors, heavily loaded with fuel containing large amounts of MA, pose safety problems caused by unfavourable reactivity coefficients and small delayed neutron fraction. A sub-critical ADS operates in a flexible and safe manner even with a core loading containing a high amount of MA leading to a high transmutation rate. Besides the reduction of the HLW burden, the MYRRHA project will serve the purpose of developing the lead alloys technology as a reactor coolant that can be used in one of the Generation IV reactor concepts namely the Lead Fast Reactor (LFR). This project will trigger the development of various innovative technologies and techniques that are of interest for various nuclear fission and fusion applications. Some of them are described in the paper. Since April 2005, MYRRHA is serving as a basis for the development of the European experimental ADS (XT-ADS) in the frame of the European Commission FP6 project EUROTRANS. The status of MYRRHA project and its capabilities as a fast neutron irradiation facility are described in this paper.