Plutonium multi recycling in pressurised water reactors of the EPR type using laser isotope separation of Pu242

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Plutonium multi recycling in a thermal spectrum with laser separation of even isotopes is not a new idea. It has been proposed by previous authors (Forsberg, 2015). They point out that even isotopes build-up when recycling in a thermal spectrum may create reactivity control challenges and parasitic neutron absorption. They also examine the effects induced by separation of isotope Pu240 on higher actinides production.A recent CEA internal report (Bréchet, 2017) mentions Pu242 laser isotope separation as a scientific possibility for plutonium recycling in PWR’s, with a standard thermal neutron spectrum. We present in this paper a theoretical plutonium AVLIS process. The acronym AVLIS stands for Atomic Vapor Laser Isotope Separation. We apply such a process to Pu242 depletion when MOX fuel comes out of the reactors to overcome even Pu isotopes build up and eliminate reactivity control problems in a thermal spectrum. We calculate quantitative results for a long term nuclear fleet consisting of PWR’s of the EPR type with UOX and MOX fuel and of the following fuel cycle facilities: classical reprocessing and MOX fabrication plants and theoretical laser isotopic depletion plants.Results show that the backlog of used MOX fuel accumulated during the operation of the thermal fleet between 1987 and 2050 (of the order of 5000 tons) can be processed in about 25 years between 2050 and 2075 and recycled in the PWR fleet in the 2050–2100 time frame. The isotopic tails with a mixture of the 5 plutonium isotopes can be reconditioned in a high content ceramic matrix and stored in a geological repository, without creating an increase in repository space too difficult to manage compared to the vitrified wastes already produced at the fuel reprocessing plant. Alternatively, the tails could undergo intermediate storage pending the arrival of fast neutron reactors to transmute them.