A Study on the Design Considerations of Vol-Oxidizer for High-Capacity Uranium Dioxide Pellets

대용량 우라늄디옥사이드 펠릿 산화를 위한 공기산화로의 설계 고려사항에 대한 연구

  • Published : 2007.04.01


This study deals with the design and implementation results for a high-capacity vol-oxidizer that can convert Uranium Dioxide pellets to $U_3O_8$ powder for up to several tens of kg HM/batch. We developed two versions of the $1^{st}$ vol-oxidizer and the $2^{nd}$ vol-oxidizer. Through an experiment with the $1^{st}$ vol-oxidizer, we deduced some problems concerning the design considerations such as the recovery rate of $U_3O_8$, the oxidation time of the Uranium Dioxide pellets, the exothermic reaction, and the powder dispersion. From the analyses of the drawbacks of the $1^{st}$ vol-oxidizer, we devised some novel items such as a folding type mesh, vibrators, and mixing blades. Also, we used the Stokes and Density ratio Eq. to determine the most reasonable flux for preventing a powder dispersion. Compared with the results of the $1^{st}$ vol-oxidizer, we showed that both the permeability of the $U_3O_8$ powders and the oxidation rate of the Uranium Dioxide pellets of the $2^{nd}$ vol-oxidizer were remarkably increased, and the temperature of the reactor was controlled well in spite of an exothermic reaction. Also, the powder was not entirely dispersed through the outlet of the voloxidizer. The experimental results of this work can help in the design of a novel and efficient vol-oxidizer with a higher capacity.


Oxidation;Uranium Dioxide;Pellet;$U_3O_8$;Vol-Oxidizer;Exothermic Reaction;Terminal Velocity


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