REFINING METHOD OF CRUDE URANIUM Russian patent published in 2019 - IPC C22B9/00 C22B60/02 C22B5/04 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy and nuclear engineering and can be used for pyrometallurgical refining of crude uranium obtained by calciothermic reduction of uranium tetrafluoride. Refining of crude uranium obtained by calciothermic method involves heat treatment of ingot in vacuum furnace with subsequent removal of non-metallic inclusions from metal surface. Thermal treatment of crude uranium ingot is carried out in several stages. First, heating and holding are carried out in a vacuum atmosphere at a temperature below the melting point of uranium, but higher than the melting point of calcium. Then, the atmosphere is changed to argon, heating to temperature higher than melting point of uranium, but lower than the boiling point of calcium, and holding at this temperature. Then the atmosphere is changed again for vacuum, heating is performed to temperature of 1,250–1,300 °C and holding at said temperature.

EFFECT: invention reduces content of impurities in refined metal and increases output of uranium in ingot to 91,1 %.

5 cl, 1 tbl