The Issue of Accelerator Beam Trips for Efficient ADS Operation
Résumé
The development of accelerator-driven systems
(ADSs) is motivated by the potential of these machines to
reduce the volume and the radiotoxicity of accumulated
nuclear waste, more particularly that of minor actinides
currently generated by the operation of existing pressurized
water reactors. The reduction of both volume and
radiotoxicity of nuclear waste is achieved by transmutation
and fission of minor actinides into less-active isotopes
or shorter-lived by-products.
Various technical challenges exist regarding designing
reliable and efficient ADSs. The key points are very
much linked to the design of the spallation module, the
assurance that reactivity remains below criticality under
any circumstances, and the accelerator reliability.
This paper addresses the latter two challenges imposed
on the accelerator in order to assure safe and
reliable ADS operation. It discusses the possibility of
performing online absolute reactivity measurements and
the limits in the number of allowable accelerator beam
trips, which might impede plant integrity and/or plant
efficiency.