RU2002121587A - A method of manufacturing a metallic uranium from uranium production wastes and equipment for its implementation - Google Patents

Claims (19)

1. A method of manufacturing metallic uranium from uranium waste, including the preparation of waste and its dissolution, obtaining nitrous oxide, dioxide, tetrafluoride and metallic uranium, refining, machining and etching metallic uranium, control and packaging of metal uranium products, characterized in that uranium production waste is used as the feedstock, and before preparing the waste, the estimated conditional mass fraction of U _{235 is} determined by the formula

where C _5calc. - estimated conditional mass fraction of U ₂₃₅ ,% in a mixture of uranium isotopes; FROM $\genfrac{}{}{0ex}{}{\text{1}}{\text{5}}$ - conditional mass fraction of U ₂₃₅ in a mixture of uranium isotopes in the first sample of waste,%; FROM $\genfrac{}{}{0ex}{}{\text{1}}{\text{0}}$ - the proportion of the mixture of uranium isotopes in the first sample of waste,%; FROM $\genfrac{}{}{0ex}{}{\text{2}}{\text{0}}$ - the proportion of the mixture of uranium isotopes in the second sample of waste,%; FROM $\genfrac{}{}{0ex}{}{\text{1}}{\text{5}}$ - conditional mass fraction of U ₂₃₅ in the mixture of uranium isotopes in the second sample of waste,%; FROM $\genfrac{}{}{0ex}{}{\text{n}}{\text{5}}$ - conditional mass fraction of U ₂₃₅ in a mixture of uranium isotopes in the nth sample of waste,%; FROM $\genfrac{}{}{0ex}{}{\text{n}}{\text{0}}$ - the proportion of the mixture of uranium isotopes in the n-th sample of waste,%; m ₁ , m ₂ , m _n - mass of uranium waste in the first, second and n-th sample of waste, respectively, g, and before refining smelting, it is adjusted to the required value according to the formula

where C _5treb. - the required value of the conditional mass fraction of U ₂₃₅ in the mixture of uranium isotopes of metallic uranium,%; FROM $\genfrac{}{}{0ex}{}{\text{1}}{\text{5}}$ - conditional mass fraction of U ₂₃₅ in the mixture of uranium isotopes for increased enrichment in the first batch of uranium metal,%; FROM $\genfrac{}{}{0ex}{}{\text{2}}{\text{5}}$ - conditional mass fraction of U ₂₃₅ in the mixture of uranium isotopes for reduced enrichment in the second batch of uranium metal,%; m ₁ , m ₂ - weight of the first and second batches of metallic uranium, respectively, g. 2. The method according to claim 1, characterized in that before using uranium waste as a feedstock, combustible materials containing uranium, metal uranium production waste and uranium metal shavings are burned. 3. The method according to claim 1, characterized in that before using the uranium waste as a raw material, estimates and stripping from the production of oxide-oxide, dioxide and uranium tetrafluoride are calcined at a temperature of 450-650 ° C. 4. The method according to claim 1, characterized in that in the production of uranium oxide-uranium, dissolution of uranium waste is carried out in concentrated nitric acid using deionized water at a temperature of 70-90 ° C to a uranium concentration of 50-70 g / l and residual acidity in solution from 150 to 250 g / l. 5. The method according to claims 1 and 4, characterized in that in the production of uranium oxide-uranium, the calcination of ammonium diuranate is carried out at a temperature of 600-650 ° C. 6. The method according to claim 1, characterized in that in the production of uranium tetrafluoride, dissolution of uranium dioxide is carried out in concentrated hydrochloric acid using deionized water at a temperature of up to 70 ° C. 7. The method according to claim 1, characterized in that the precipitation of uranium tetrafluoride from the solution is carried out by a dosed supply of 40% hydrofluoric acid at a temperature of 50-60 ° C for 2-3 hours 8. The method according to PP.1, 6 and 7, characterized in that the preliminary drying of uranium tetrafluoride to a powder state is carried out under incandescent lamps with a capacity of 1000-1500 kW at a temperature of 40-60 ° C. 9. The method according to claims 1, 6-8, characterized in that the final drying and calcination of uranium tetrafluoride is carried out in hydrogen furnaces in two stages: at a temperature of 110-250 ° C for 1.5-5.5 hours, at a temperature up to 550 ° C for 1.0-3.5 hours with a hydrogen flow rate of 10-20 l / min. 10. The method according to claims 1 to 9, characterized in that during the thermal reduction of metallic uranium, granular calcium is used with a granule size of 1-3 mm. 11. The method according to claims 1-10, characterized in that the machining of ingots of metal uranium is carried out with a spindle speed of 25-150 min ^-1 and a cutting depth of up to 3 mm. 12. The method according to claims 1 to 11, characterized in that the etching of products from metallic uranium is carried out in nitric acid, followed by washing in deionized water. 13. The method according to claims 1-12, characterized in that the packaging of metal uranium products in plastic bags is carried out in an inert gas environment using argon or nitrogen. 14. Equipment for the manufacture of metallic uranium from uranium production waste, containing installations for burning and calcining production and uranium waste, solvent reactors, extractor strippers, uranium tetrafluoride precipitation reactor, stirrers, solution containers, containers, filtration plants, drying and calcining furnaces , hydrogen furnaces, a plant for calcium thermal reduction of uranium, a vacuum refining furnace, a lathe, etching baths, control and packaging plants, characterized in that The uranium oxide oxide production consists of a solvent reactor, filtration units, a reextractor extractor, and an annealing furnace connected to a single continuous production line, and uranium tetrafluoride production equipment, including a tetrafluoride precipitation reactor, a stirrer, solution containers, and tetrafluoride containers lined with ftoroplast. 15. Equipment according to claim 14, characterized in that the filtration units comprise nutsche filters made of vinyl plastic. 16. Equipment according to claims 14 and 15, characterized in that the movement of uranium-containing products between technological operations is carried out in a nuclear-safe container. 17. Equipment according to claims 14-16, characterized in that it is manufactured in a nuclear-safe geometry. 18. Equipment according to claims 14-17, characterized in that the calcination and drying of uranium tetrafluoride is carried out in graphite crucibles. 19. Equipment according to claims 14-18, characterized in that it is located in the following sequence: uranium production waste incineration and calcination plants, solvent reactor, filtration unit, extractor strippers, uranium tetrafluoride precipitation reactor, solution containers, installation filtration, calcination furnace, rotary hydrogen furnace, BVTP furnace, sliding furnace, solvent reactor, filtration unit, hydrogen furnace, calcium thermal reduction unit, vacuum refining furnace, turning suspended machine, etching baths, packaging installation.