Engineering Design of a High-Capacity Vol-Oxidizer for Handling UO2 Pellets of Tens of Kilogram

• Published in: Journal of nuclear science and technology 2008-07, Vol.45 (7), p.617-624
• Main Authors: KIM, Young Hwan, LEE, Hyo Jik, LEE, Jong Kwang, JUNG, Jae Hoo, PARK, Byung Suk, YOON, Ji Sup, PARK, Seong Won
• Format: Article
• Language: English
• Subjects: Applied sciences; Energy; Exact sciences and technology; Fuels; Nuclear fuels; Preparation and processing of nuclear fuels
• ISSN: 0022-3131; 1881-1248
• DOI: 10.3327/jnst.45.617

This study deals with the design and implementation results for a high-capacity vol-oxidizer (HCV) that can convert UO2 pellets of up to several tens of kgHM/batch to U3O8 powder. Before fabricating the HCV, we fabricated a prototype that can process such a high capacity. From the analyses of some drawbacks of the prototype, we devised a couple of novel innovations such as a folding-type mesh, vibrators, and mixing blades. We used the Stokes equation to theoretically determine the most reasonable flux so as not to cause U3O8 powder dispersion during oxidation. Compared with the results of the prototype, we showed that both the recovery rate of the U3O8 powders and the oxidation rate of the UO2 pellets of the HCV were remarkably increased due to the folding-type mesh, vibrator and mixing blades, and the temperature was controlled stably in spite of the exothermic reaction due to the mixing blades along with the rotational mesh. Also, no powder was dispersed through the exhaust line of the HCV within the air flux calculated using the Stokes equation. The experimental results of this study are valuable in terms of being the first vol-oxidation of tens of kg in the world. Based on this study, a more efficient and higher capacity vol-oxidizer is expected to be developed.