French Perspective On The Respective Interests Of Hydro- And Pyro-Chemical Processes For Recycling Future Spent Nuclear Fuels

For more than 25 years, France has operated the treatment and recycling of spent nuclear fuels at an industrial scale in the AREVA La Hague and MELOX plants. This industrial success story has been based on the historical PUREX separation process which allows the U and Pu separation from the fission products and minor actinides thanks to their selective extraction by the TriButylPhosphate non-miscible molecules. Beyond the initial PUREX process, more innovative processes have been developed and tested at representative scale, such as (U,Pu) co-management separation process or different minor actinides enhanced partitioning processes. Liquid/liquid extraction processes hence demonstrated their suitability both to be industrially deployed and to be upgraded and extended towards additional recycling objectives for oxides fuels. In the same time, pyrochemical processes have been developed since the early 60's for recycling of the metallic fuels. Later on, this process was implemented at the pilot scale for recovering uranium from sodium bonded metallic fuel of the EBR2 reactors. Laboratory scale processes have also been developed for recovering the plutonium and the minor actinides by using a reactive cadmium cathode. More recently, Korea developed such type of processes at the engineering scale, on surrogate materials. The long term aim is to recycle current commercial spent nuclear fuels.Furthermore, most of the future 4th generation nuclear systems plan to expand the actinides recycling, for allowing a better use of natural uranium. Uranium-238 efficient consumption would hence be possible thanks to the Pu-multirecycling in fast neutrons reactors. Recycling would therefore be the core of future nuclear energy systems with a strong requirement of efficiency and safety. From the current situation, two main routes seem to be envisaged for recycling future commercial spent nuclear fuels, pyro- or hydro-processes. This paper aims to depict the respective values of both types of processes for future fuel cycles and assess what could be their most relevant potential targets.