Decontamination of uranium contaminated metals - 15 years of experience - 15528
Uranium contaminated waste is somewhat of a special case among radioactive waste as the uranium, if enriched, also is a valuable asset. Incineration and pyrolysis of uranium contaminated dry active waste (DAW) was covered during WM'14. Uranium contaminated metals is however somewhat different when it comes treatment and recovery of uranium. Since the late 1990's the Metals Treatment and Recycling Facility in Studsvik Sweden has treated approximately 1500 tonnes of metals contaminated by uranium. Depending on the metal, melt-decontamination may or may not be a way of salvaging metals if the pre-treatment was not enough. The only metals that currently are subject to melt decontamination are iron based materials as well as lead. Other metals such as aluminium, brass and copper must all be cleaned prior to melting. Recovery of uranium from the secondary waste is most likely economically feasible only from the first step, the pre-melting decontamination, as the slag is just that, a slag, which is molten at a high temperature, and thereafter cooled under non-controlled conditions so uranium is trapped inside in an unspecified chemical form. This paper will describes experiences and lessons learned from 15 years of treatment, including melt-decontamination, of uranium contaminated metals. (authors)