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

  • Byoungjin So (Advanced Fuel Cycle Technology Division, Korea Atomic Energy Research Institute) ;
  • Ju Ho Lee (Advanced Fuel Cycle Technology Division, Korea Atomic Energy Research Institute) ;
  • Jae Won Lee (Advanced Fuel Cycle Technology Division, Korea Atomic Energy Research Institute) ;
  • Yung Zun Cho (Advanced Fuel Cycle Technology Division, Korea Atomic Energy Research Institute)
  • Received : 2024.03.04
  • Accepted : 2024.06.25
  • Published : 2024.11.25

Abstract

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.

Keywords

Acknowledgement

This study was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (Grant no. 2021M2A7A1080748).

References

  1. International Atomic Energy Agency, Management of Damaged Spent Nuclear Fuel, IAEA Nuclear Energy Series No. NF-T-3.6, IAEA, Vienna, 2009.
  2. J.-W. Lee, J.-W. Lee, J.-H. Kim, S.-P. Yim, Y.-W. Lee, M.-S. Yang, Study of the Characteristics and Sinterability of DUPIC powder by using simulated fuel, J. Nucl. Sci. Technol. 39 (3) (2014) 721-724.
  3. G.I. Park, J.W. Lee, J.W. Lee, Y.W. Lee, K.C. Song, Effect of impurities on the microstructure of dupic fuel pellets using the simfuel technique, Nucl. Eng. Technol. 40 (3) (2008) 191-198. https://doi.org/10.5516/NET.2008.40.3.191
  4. S.-C. Jeon, J.-W. Lee, S.-J. Kang, J.-H. Lee, J.-W. Lee, G.-I. Park, I.-T. Kim, Temperature dependences of the reduction kinetics and densification behavior of U3O8 pellets in Ar atmosphere, Ceram. Int. 41 (2015) 657-662. https://doi.org/10.1016/j.ceramint.2014.08.118
  5. S.-C. Jeon, J.-W. Lee, J.-Y. Yoon, Y.-Z. Cho, D.-J. Kim, D.S. Kim, K.S. Kim, J.H. Kim, J.H. Yang, Stimulation of densification during the reduction of U3O8 to UO2 by atmosphere control, Ceram. Int. 45 (2019) 6863-6868. https://doi.org/10.1016/j.ceramint.2018.12.181
  6. M. Pijolat, C. Brun, F. Valdivieso, M. Soustelle, Reduction of uranium oxide U3O8 to UO2 by hydrogen, Solid State Ionics 101-103 (1997) 931-935. https://doi.org/10.1016/S0167-2738(97)00385-8
  7. W.D. Cho, M.-H. Han, M.C. Bronson, Y. Zundelevich, Processing of uranium oxide powders in a fluidized-bed reactor. I. Experimental, J. Nucl. Mater. 205 (2002) 106-111.
  8. R.A. Kuhnel, H.J. Roorda, J.J. Steensma, The crystallinity of minerals - a new variable in pedogenetic processes: a study of goethite and associated silicates in laterites, Clay Clay Miner. 23 (1975) 349-354. https://doi.org/10.1346/CCMN.1975.0230503
  9. P.R. Roy, H.S. Kamath, Sintering technology in the manufacture of nuclear fuels, Solid State Phenom. 8&9 (1989) 415-432.
  10. International Atomic Energy Agency, Thermodynamics and Transport Properties of Uranium Dioxide and Related Phases, Technical Report Series No. 39, IAEA, Vienna, 1965.
  11. J.M. Elorrieta, L.J. Bonales, N. Rodriguez-Villagra, V.G. Baonza, J. Cobos, A detailed Raman and X-ray study of UO2+x oxides and related structure transitions, Phys. Chem. Chem. Phys. 18 (2016) 28209-28216. https://doi.org/10.1039/C6CP03800J
  12. R. Furuichi, T. Ishii, T. Nakane, Thermoanalytical study on the oxidation of uranium dioxides derived from uranyl nitrate, uranyl acetate and ammonium diuranate, Thermochim. Acta 33 (1979) 51-67. https://doi.org/10.1016/0040-6031(79)87029-X
  13. J.M. MacEachern, P. Taylor, A review of the oxidation of uranium dioxide at temperatures below 400 ℃, J. Nucl. Mater. 254 (1998) 87-121. https://doi.org/10.1016/S0022-3115(97)00343-7
  14. S. Yajima, H. Furuyam T. Hirai, Lattice and grain-boundary diffusion of uranium in UO2, J. Nucl. Mater. 20 (2) (1966) 162-170. https://doi.org/10.1016/0022-3115(66)90004-3
  15. D.E.Y. Walker, The oxidation of uranium dioixdes, J. Appl. Chem. 15 (1965) 128-135. https://doi.org/10.1002/jctb.5010150304
  16. P.E. Blackburn, J. Weissbart, E.A. Gulbransen, Oxidation of uranium dioxide, J. Phys. Chem. 62 (8) (1958) 902-908. https://doi.org/10.1021/j150566a002
  17. M. Foldvari, Handbook of Thermogravimetric System of Minerals and its Use in Geological Practice, Geological Institute of Hungary, 2011.
  18. H.E. Kissinger, Reaction kinetics in differential thermal analysis, Anal. Chem. 29 (1957) 1702-1706. https://doi.org/10.1021/ac60131a045
  19. U.B. Ceipidor, E. Brizzi, R. Bucci, A.D. Magri, Using thermoanalytical data. Part 7. DSC/DTA/DTG peak shapes depending on operational settings, equipment features, sample kinetic and thermodynamic parameters, Thermochim. Acta 247 (2) (1994) 347-356. https://doi.org/10.1016/0040-6031(94)80134-7
  20. H.E. Kissinger, Variation of peak temperature with heating rate in differential thermal analysis, J. Res. Natl. Bur. Stand. 57 (1956) 217-221. https://doi.org/10.6028/jres.057.026
  21. J.S. Killingley, S.J. Day, Dehydroxylation kinetics of kaolinite and montmorillonite from Queensland Tertiary oil shale deposits, Fuel 69 (1990) 1145-1149. https://doi.org/10.1016/0016-2361(90)90072-X
  22. J.G. Cabrera, M. Eddleston, Kinetics of dihydroxylation and evaluation of the crystallinity of kaolinite, Thermochim. Acta 70 (1-3) (1983) 237-247. https://doi.org/10.1016/0040-6031(83)80198-1
  23. L. Mandelkern, Crystallization of Polymers: Volume 2, Kinetics and Mechanisms, second ed., Cambridge University Press, Cambridge, 2004.