METHOD FOR RECOVERING FUEL IN THE FORM OF URANIUM ISOTOPE HEXAFLUORIDE MIXTURE BURNT UP IN NUCLEAR REACTOR FOR ITS REUSE IN NUCLEAR REACTOR Russian patent published in 2007 - IPC G21C19/42 B01D59/20 

FIELD: recycling technology for power-generating nuclear materials.

SUBSTANCE: concentration of uranium-235 fissionable isotope is raised above source content to desired value of 2-5 mass percent by direct enrichment in cascade of gas centrifuges. Uranium-235 concentration in cascade dump is 0.1-0.3 mass percent. At the same time uranium isotope mixture having lower concentration of uranium-232 and uranium-236 isotopes than burnt-up source mixture is thinned with hexafluoride. To this end uranium-thinner hexafluoride is introduced to interstage stream of cascade at same or almost same concentration of uranium-235 fissionable isotope. For thinning use is made of hexafluoride of natural mixture of uranium isotope, hexafluoride of uranium isotope mixture separated from burnt-up nuclear fuel, as well as mixture of source uranium isotope burnt-up mixture and hexafluoride of natural mixture of uranium isotopes or hexafluoride of uranium isotope mixture separated from burnt-up nuclear fuel.

EFFECT: ability of producing marketable uranium hexafluoride at minimal quantity of uranium-separating factory facilities used for thinner production.

16 cl, 3 dwg, 3 tbl