METHOD FOR TREATMENT OF MOLYBDENUM-CONTAINING HEAVY SOLUTIONS AND CONCENTRATES OF LONG-LIVING RADIONUCLIDES PRODUCED IN RECOVERY OF IRRADIATED FISSIONABLE FUEL AT NUCLEAR POWER PLANTS Russian patent published in 2001 - IPC

FIELD: radiochemical technology; recovery of heavy-water nitric-acid solutions (raffinates) obtained in reconditioning irradiated nuclear fuel. SUBSTANCE: method is proposed for use in sophisticated waste fractionating systems in the framework of Modified Purex Process for solidifying liquid wastes to form matrices and for burying long-living radionuclides as well as products of fission whose vitrification involves some difficulties. Method involves recovery deposition of molybdenum from solution by way of reverse deposition with excess hydrazine hydrate, its additional deposition using concentrate of fission products and transuranium elements, and production of blocks of molybdenum, zirconium, neptunium, rare-earth and transuranium elements convenient for storage. In this way, radioactive liquid wastes are solidified to form matrices of concentrates of fission-product elements and long-living radionuclides without introducing additional salt-forming substances. EFFECT: improved localization of fission-product elements, eliminated volatility of molybdenum compounds in the course of molding powder production. 7 cl