METHOD OF RECYCLING RADIONUCLIDE-CONTAMINATED METAL WASTES Russian patent published in 2016 - IPC G21F9/00 

FIELD: processing and recycling of waste.

SUBSTANCE: invention relates to method of processing and recycling of metal wastes contaminated with radionuclides. Method involves fragmentation of wastes, control of radioactive contamination of fragments with calculation of permissible level, melting in induction furnace in air with addition of refining fluxes, guidance and removal of slag, pouring and control of metal ingots. At that, after monitoring radioactive contamination of waste in case of exceeding calculated permissible level, first thermal deactivation of all metal wastes is conducted by calcination in air at 700-800°C for 15-20 minutes with subsequent cooling to 30-40°C and vibration treatment with frequency of 2500-3000 oscillations/min and amplitude of oscillations of 0.5-2.0 mm for 4-6 minutes. Then recyclable wastes are divided into wastes of copper and alloys based thereon that are directed in re-melting, and wastes from ferrous alloys, which, before re-melting are subjected to additional mechanical deactivation for 20-30 minutes at shot-blasting plant. Melting of metal wastes of copper and alloys on its base is carried out separately from wastes of ferrous alloys, melting of whole range of metal wastes is performed with single guidance and single removal of entire volume of slag.

EFFECT: high efficiency of cleaning metal wastes from radionuclides, including by ⁶⁰Co≈ in 3 times, by ¹⁰⁶Ru≈ in 11 times, by ⁵⁴Mn≈ in 4 times and reducing volume of secondary disposed radioactive wastes in comparison to prototype in 5-12 times.

1 cl, 2 tbl, 2 ex