Acceleration of reduction of U3O8 to UO2 by particle rearrangement in a vertically-shaken bed

The stabilization technology for damaged nuclear fuels requires physically-stable pellets, so powders that are used for the process must have high sinterability. Due to safety limitations in H2 concentration, fuel materials are reduced with high gas flow rates or for long times in cyclic oxidation and reduction process. We attempted to shorten the reaction time by shaking the powder reactor vertically. This method reduced the reaction time for the reduction process by two-thirds compared to that required in the static condition. The shaking process had a negligible effect on the quality of the powder. Therefore, this method can be applied to the reduction processes that require large volumes and long reaction times.