Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-17T17:20:54.973Z Has data issue: false hasContentIssue false
  • English
  • Français

Grain Size and Burnup Dependence of Spent Fuel Oxidation: Geological Repository Impact

Published online by Cambridge University Press:  10 February 2011

E. J. Kansa ,
B. D. Hanson  and
R. B. Stout
E. J. Kansa
Affiliation:
Earth and Environmental Sciences Directorate, Lawrence Livermore National Laboratory, P.O. Box 808, L-200, Livermore, CA 94551-9989 (kansal@llnl.gov)
B. D. Hanson
Affiliation:
Pacific Northwest National Laboratory, P.O. Box 999, Mail Stop P7-27, Richland, WA 99352
R. B. Stout
Affiliation:
Earth and Environmental Sciences Directorate, Lawrence Livermore National Laboratory, P.O. Box 808, L-200, Livermore, CA 94551-9989 (kansal@llnl.gov)
Get access

Abstract

Further refinements to the oxidation model of Stout et al. have been made. The present model incorporates the burnup dependence of the oxidation rate and an allowance for a distribution of grain sizes. The model was tested by comparing the model results with the oxidation histories of spent-fuel samples oxidized in thermogravimetric analysis (TGA) or oven dry-bath (ODB) experiments. The experimental and model results are remarkably close and confirm the assumption that grain-size distributions and activation energies are the important parameters to predicting oxidation behavior. The burnup dependence of the activation energy was shown to have a greater effect than decreasing the effective grain size in suppressing the rate of the reaction U4O9→U3O8. Model results predict that U3O8 formation of spent fuels exposed to oxygen will be suppressed even for high burnup fuels that have undergone restructuring in the rim region, provided the repository temperature is kept sufficiently low.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 556: Symposium QQ – Scientific Basis for Nuclear Waste Management XXII , 1999 , 455
Copyright
Copyright © Materials Research Society 1999

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Einziger, R.E., and Strain, R.V., “Behavior of breached pressurized water reactor spent-fuel rods in an air atmosphere between 250 and 360°C,” Nucl. Technol. 75:82–95(1986).Google Scholar
2. Gray, W.J., Thomas, L.E., and Einziger, R.E., Mat. Res. Soc. Symp., 294:47 (1993).Google Scholar
3. Matzke, H., Ottaviani, J., Pellottiero, D., and Rouault, J., “Oxygen potential of high burnup fast breeder oxide fuel,” J. Nucl. Mater. 160:142–146(1988).Google Scholar
4. Walker, C.T., Kamesama, T., Kitajima, S., and Kinoshita, M., “Concerning the microstructural changes that occur at the surface of U0 2 pellets on irradiation to high burnup,” J. Nucl. Mater. 188:73–79 (1992).Google Scholar
5. Hanson, B. D., “The Burnup Dependence of Light Water Reactor Spent Fuel Oxidation,” (PNNL-11929) Richland, WA: Pacific Northwest National Laboratory (July 1988).Google Scholar
6. McEachern, R.J., Choi, J.W., Kolar, M., Long, W., Taylor, P., and Wood, D.D., “Determination of the activation energy for the formation of U30 8 on U0 2,” J. Nucl. Mater. 249:58–69 (1997).Google Scholar
7. McEachern, R.J., Doern, D.C., and Wood, D.D., “The effect of rare-earth fission products on the rate of U30 8 formation on U0 2,” J. Nucl. Mater. 252:145–149(1998).Google Scholar
8. Thomas, L.F., and Einziger, R.E., “Grain boundary oxidation of pressurized-water reactor spent fuel,” Mater. Charact. 28:149–156 (1992).Google Scholar
9. Stout, R.B., Shaw, H.F., and Einziger, R.E., “Statistical model for grain boundary and grain volume oxidation kinetics in UO 2 spent fuel,” (UCRL-100859) Livermore, CA: Lawrence Livermore National Laboratory (1989).Google Scholar
10. Stout, R.B, Kansa, E.J., Einziger, R.E., Buchanan, H.C., and Thomas, L.E., “Spent fuel waste form characteristics: Grain and fragment size statistical dependence for oxidation response,” in High Level radioactive Waste Management, (2nd Annual Int. Conf, Amer. Nucl. Soc. and Amer. Soc. Civ. Eng., 1:103–111, LaGrange Park, IL, 1991).Google Scholar
11. Stout, R.B., and Leider, H. R., Waste Form Characteristics Report: Revision 1, Version 1.2, (UCRL-ID-108314 Version 1.2) Livermore, CA: Lawrence Livermore National Laboratory (1997).Google Scholar
12. Stout, R.B., and Leider, H. R., Waste Form Characteristics Report: Revision 1, Version 1.3, (UCRL-ID- 108314, Version 1.3) Livermore, CA: Lawrence Livermore National Laboratory (1998).Google Scholar
13. Thomas, L.E., Slagle, O.D., and Einziger, R.E, “Nonuniform oxidation of LWR spent fuel in air,”. Nucl. Mater. 184:117–126 (1991).Google Scholar
14. Thomas, L.E., Einziger, R.E, and Woodley, R.E.,”Microstructural examination of oxidized spent PWR fuel by transmission electron microscopy,”. Nucl. Mater. 166:243–251 (1989).Google Scholar