Study of the volatilization of cesium and rhenium in the waste vitrification process

A side effect of high level waste vitrification at 1100 °C is the volatilization radioactive cesium (Cs), recaptured further on in process as a solid aerosol by dust scrubber. Feedback from industry suggests that Cs combines with technetium (Tc) – simulated here rhenium (Re), chosen for its similar behavior to form volatile species. This work characterized and formation. The first experiment involved elaborating analyzing simplified glass enriched Re, which reinforce phenomena. results showed demixed liquid phase rich Cs, Mo, Na formed melt, reminiscent molybdic evoked literature. Moreover, condensed gasses led conclusion alkalis Re volatilize congruently around 700 °C. In second experiment, series measurements gas aerosols throughout process. size distribution particles furnace were mostly submicronic, calciner scrubber included nanoparticles micronic particles. SEM-EDS characterization revealed composition spherical particle made two nested phases: one Cs-Re-O, other Na-Mo-O. analyses performed could be found every sampled process, might originate aggregation submicronic because similarities. Thus, observations better understanding elements interest both melt phase.