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Dissolution Rates of DWPF Glasses from Long-Term PCT

Published online by Cambridge University Press:  03 September 2012

W. L. Ebert
Affiliation:
Chemical Technology Division, Argonne National Laboratory, Argonne, IL 60439
S.-W. Tam
Affiliation:
Chemical Technology Division, Argonne National Laboratory, Argonne, IL 60439
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Abstract

We have characterized the corrosion behavior of several Defense Waste Processing Facility (DWPF) reference waste glasses by conducting static dissolution tests with crushed glasses. Glass dissolution rates were calculated from measured B concentrations in tests conducted for up to five years. The dissolution rates of all glasses increased significantly after certain alteration phases precipitated. Calculation of the dissolution rates was complicated by the decrease in the available surface area as the glass dissolves. We took the loss of surface area into account by modeling the particles to be spheres, then extracting from the short-term test results the dissolution rate corresponding to a linear decrease in the radius of spherical particles. The measured extent of dissolution in tests conducted for longer times was less than predicted with this linear dissolution model. This indicates that advanced stages of corrosion are affected by another process besides dissolution, which we believe to be associated with a decrease in the precipitation rate of the alteration phases. These results show that the dissolution rate measured soon after the formation of certain alteration phases provides an upper limit for the long-term dissolution rate, and can be used to determine a bounding value for the source term for radionuclide release from waste glasses. The long-term dissolution rates measured in tests at 20,000 m−1 at 90°C in tuff groundwater at pH values near 12 are about 0.2,0.07, and 0.04 g/(m2•d) for the Environmental Assessment glass and glasses made with SRL 131 and SRL 202 frits, respectively.

Type
Research Article
Copyright
Copyright © Materials Research Society 1997

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References

REFERENCES

1. Lemmens, K. and Van Isegham, P., Mater. Res. Soc. Symp. Proc. 257, 4956 (1992).Google Scholar
2. Feng, X., Bates, J. K., Buck, E. C., Bradley, C. R., and Gong, M., Nucl. Technol. 104 (2), 193206 (1993).Google Scholar
3. Ebert, W. L., Bates, J. K., Buck, E. C., and Bradley, C. R., Mater. Res. Soc. Symp. Proc. 294, 569576 (1993).Google Scholar
4. Ebert, W.L., Bakel, A.J., and Brown, N. R., in Proceedings International Topical Meeting on Nuclear and Hazardous Waste Management, Spectrum '96, Seattle, WA, August 18–23, 1996, pp. 569575 (1996).Google Scholar
5. Grambow, B., Nuclear Waste Glass Dissolution: Mechanism, Model, and Application, JSS Report 87–02 (1987).Google Scholar
6. Advocat, T., Crovisier, J.L., Fritz, B., and Vernaz, E., Mater. Res. Soc. Symp. Proc. 176, 241248 (1990).Google Scholar
7. Strachan, D. M., Bourcier, W. L., and McGrail, B. P., Radioactive Waste Management and Environmental Restoration 19, 129145 (1994).Google Scholar
8. Van Iseghem, P. and GramBow, B., Mater. Res. Soc. Symp. Proc. 112, 631639 (1988).Google Scholar
9. Ebert, W. L., Bates, J. K., Bradley, C. R., Buck, E. C., Dietz, N. L., and Brown, N. R., Ceram. Trans. 39, 333340 (1993).Google Scholar
10. Feng, X.T, Mater. Res. Soc. Symp. Proc. 333, 5568 (1994).Google Scholar
11. Bates, J. K., Ebert, W. L., Mazer, J. J., Bradley, J. P., Bradley, C. R., and Dietz, N. L., Mater. Res. Soc. Symp. Proc. 212, 7787 (1991).Google Scholar
12. Bates, J. K. and Tšteindler, M.T, Mater. Res. Soc. Symp. Proc. 15, 8390 (1983).Google Scholar
13. Bakel, A. J., Ebert, W. L., and Luo, J. S., Ceram. Trans. 61, 515322 (1995).Google Scholar
14. McGrail, B. P. and Peeler, D. K., Evaluation of the Single-Pass Flow-Through Test to Support a Low-Activity Waste Specification, Pacific Northwest Laboratory Report PNL-10746 (1995).Google Scholar
15. Bourcier, W. L., Carroll, S. A., and Phillips, B. L., Mater. Res. Soc. Symp. Proc. 333, 507512 (1994).Google Scholar
16. Knauss, K. G., Bourcier, W. L., McKeegan, K. D., Merzbacher, C. I., Nguyen, S. N., Ryerson, F. J., Smith, D. K., and Weed, H. C., Mater. Res. Soc. Symp. Proc. 176, 371381 (1990).Google Scholar
17. Ebert, W. L., and Bates, J. K., Nuclear Technol. 104 (3), 372384 (1993).Google Scholar
18. Bates, J. K., et al. , ANL Technical Support Program for DOE Environmental Restoration and Waste Management. Annual Report October 1993-September 1994, Argonne National Laboratory Report ANL-95/20 (1995).Google Scholar