DEVELOPMENT OF FLUORINATION DECONTAMINATION TECHNIQUE FOR URANIUM BEARING WASTES

摘要

A matrix of uranium bearing wastes (sludge, incineration ashes) bonds uranium tightly, and some wastes (narrow pipes, filters, etc.) have complicated shapes. This research was intended to achieve the assumed clearance level (0.3Bq/g) and to reduce the amount of secondary wastes. One of the uranium decontamination processes is the fluorination decontamination process in which ClF_3 is used as a decontamination agent to fluoriate uranium bearing wastes to gaseous UF_6 which can be recovered by cold or chemical trapping. The research test variables were decontamination temperature, decontamination temperature history and decontamination period. Filters and the main sludge could be decontaminated below the assumed clearance level when treated at 500°C for 3 hours.