Hydrothermal oxidation of radioactive combustible waste

A hydrothermal processing system was designed, built and tested for treatme nt of transuranic combustible material. The operation is performed in a plu tonium glovebox. Presented in this paper are results from the study of the hydrothermal oxidation of plutonium and americium contaminated organic wast es. The use of thermal liquefaction, via pyrolysis, to prepare solid materi als for hydrothermal processing was tested and compared to the pumping of s lurries of small particle sized solids (ion exchange resin). Experiments sh ow that the hydrothermal process converts greater than 99.9% of the organic component to CO2 and H2O, with 30 wt% H2O2 as an oxidant, at 540 degrees C and 46.2 MPa. The majority of the actinide component forms insoluble produ cts that are easily separated by filtration. A titanium liner in the reacto r and heat exchanger provides corrosion resistance for the oxidation of chl orinated organics. Published by Elsevier Science Ltd.