The objective of the Mini-INCA project is to study minor-actinide transmutation processes in high intensity thermal neutron fluxes, in view of proposing solutions to reduce the radiotoxicity of long-lived nuclear wastes. The fission process is the best way to reduce radiotoxicity and also to use the total amount of energy contain within heavy nuclei. Unfortunately, in the thermal energy domain (below the first reaction resonances), the most abundant minor actinides in the spent fuel inventory have very small fission cross sections. It is then necessary to “transmute” these fertile nuclei into fissile nuclei by neutron capture. The drawback of this method is the production of heavy nuclei that can be even more radiotoxic than the initial nucleus.
Complex transmutation chains should then be characterised by studying the different reaction cross sections (capture and fission) involved within the process.
These studies have started within the framework of the French act of 30 December 1991 on the management of nuclear radioactive wastes.
Experiments are performed at the high flux research reactor of the Laue-Langevin institute, in Grenoble. This reactor has one of the highest neutron flux in the world and offers, via the experimental installation of the mini-INCA project, very moderated neutrons with intensity and energy spectra that can be selected.
Dapnia has the full responsibility of the project.
It has constructed and installed a gamma- and alpha-spectroscopy station which is connected to an irradiation channel (H9) share with the Lohengrin spectrometer.
It has also the full management of the irradiation channel, called V4, which is used for transmutation studies and gives access to the highest neutron flux in the world.