A FLUID-BED PROCESS FOR THE DIRECT CONVERSION OF URANIUM HEXAFLUORIDE TO URANIUM DIOXIDE

摘要

A new, dry process for the production of uranium dioxide powder from uranium hexafluoride by fluidization and particle-coating techniques has been developed. The process involves direct conversion of uranium hexafluoride to a solid, uranyl fluoride, by hydrolysis with steam and the reduction of the uranyl fluoride to the dioxide by reaction with steam-and-hydrogen mixtures. Development work on the process was carried out in 3-in.-diameter Monel reactors.nThe uranium hexafluoride-steam reaction was carried out continu¬ously at relatively low temperatures, about 200 C, at rates equivalent to 174 lb uranium/(hr)(sq ft reactor cross section). Nominal operating con¬ditions during hydrolysis runs included a superficial gas velocity of 0.75 ft/ sec, an 8-kg bed of uranyl fluoride, equivalent to about a 20-in. static bed height, and a seed particle (uranyl fluoride) addition rate of 0.9 kg/hr.