DISTRIBUTION OF TUNGSTEN AND NATURAL RADIONUCLIDES IN THE PRODUCTS OF FLUORIDE PROCESSING OF ZIRCONIUM CONCENTRATES

摘要

The natural radionuclides in the course of the processing of the zirconium concentrates using the hydrogen difluoride scheme concentrate completely in the sludge in the ZrF_4 distillation stage or in the precipitate upon dissolution of the desilicated concentrate after its re-fluorination.The tungsten concentrates in the desilicated product, and in the ZrF_4 distillation stage it splits between the gas phase and the sludge (WO_2 and W_4O_(11)) in the ratio 1:4. Hydrolysis of the WO_2F_2 vapors separates WO_3 with purity 99.9 percent.Two-stage (repeat) fluorination of the zirconium concentrate as a result of the secondary extraction of the zirconium leads to reduction of the mass of the sludge to 3-4 percent and increase of the tungsten content in the sludge by 19.8 times and increase of the content of the radionuclides by 26.4 times in comparison with the starting concentrate.The relations governing the concentration of the natural radionuclides in the products of the processing of the Algoma zirconium concentrate make it possible to predict their distribution in ores of the same mineralogical type with any radioactivity level.