IRRADIATED NUCLEAR FUEL EXTRACTION PROCESSING METHOD Russian patent published in 2020 - IPC G21C19/46 

FIELD: nuclear physics and equipment.

SUBSTANCE: invention relates to extraction technology of irradiated nuclear fuel processing. Uranium, plutonium and associated elements are extracted from a nitrate solution, the extract is washed, re-extracting plutonium with a portion of uranium, washing the uranium extract from plutonium, neptunium and technetium residues, correcting the plutonium re-extract based on nitric acid content and oxidising plutonium (III) to plutonium (IV), repeatedly extracting plutonium with part of uranium, washing the extract of repeated extraction and repeatedly re-extracting plutonium. First re-extraction of plutonium with a portion of uranium is carried out with an aqueous stream containing reducers for plutonium (IV) and technetium (VII) at high ratio up to O:B = 35. Final purification of the uranium extract is carried out with a slightly acid complexone solution. Used complexone solution is delivered for washing of uranium-plutonium extract, concentrated nitric acid is added to the plutonium-technetium re-extract to a content of not less than 3 mol/l and passed through a catalytic oxidation column with a carbon catalyst. Treated re-extract is directed to affinity block. Plutonium re-extract with part of uranium is removed from process, and organic flow is directed to head extractor.

EFFECT: invention reduces volume of liquid radioactive wastes.

6 cl, 2 dwg, 3 tbl