Possible use of accelerator driven subcritical reactors for minor actinides incineration

The possible interest of accelerator driven subcritical reactors for minor actinides incineration is examined. The physics of neutron multiplying systems is recalled. The differences between critical and subcritical reactors' control are described, with emphasis on the importance of the delayed neutrons fraction. The minor actinides fuel evolution is studied with the conclusion that fast neutron spectra are clearly more efficient then thermal neutron spectra. It is, also, shown that characteristic times for incineration should be in the order of 10 years. The number of minor actinides incinerators necessary for 60 PWRs is estimated to be about 6 with total thermal power of 9 GW. These reactors will, also, be able to transmute essentially all 99Tc and 129I produced by the 60 PWR. The excess electricity cost for MA incineration is estimated to be about 5%. (authors)