Skip to main content Accessibility help
×
Home

Vitrification of simulated highly active calcines containing high concentrations of sodium and molybdenum

  • Mike T. Harrison (a1) and Carl J. Steele (a2)

Abstract

Sodium carbonate is currently being considered as a wash-out reagent for the removal of the settled solids in the unagitated Highly Active Liquor (HAL) storage tanks at Sellafield. As the settled solids are expected to comprise mainly zirconium molybdate (ZM), this will result in a challenging feed to the Waste Vitrification Plant (WVP) containing high concentrations of both molybdenum and sodium.

In previous studies, it was shown that at high wash-out waste loadings, i.e. 10 – 12 wt% MoO3 incorporation, there was very little tolerance in ‘Ca/Zn’ base glass for extra sodium before the formation of significant separated sodium molybdate salt phase. However, higher amounts of sodium can be accommodated in borosilicate glasses if the wash-out waste loading is reduced. Further studies have now been carried out to investigate the vitrification of more representative calcined waste feeds. Both pure zirconium molybdate (ZM) and blended ZM-reprocessing waste calcines were produced from the appropriate liquor feeds. The maximum waste incorporations of these two calcines in ‘Ca/Zn’ base glass have been determined, along with a complete product quality assessment. This assessment included measuring the bulk density, degree of crystallinity, heat treatment, durability (Soxhlet and PCT), glass transition temperature, and viscosity.

Copyright

Corresponding author

References

Hide All
1. Harrison, M. T., Procedia Materials Science, 7, 1015 (2014).
2. Edmondson, M. J., Maxwell, L. J., Ward, T. R., A Methodology for Post Operational Clean Out of a Highly Active Facility Including Solids Behaviour -12386, Waste Management Symposium 2012.
3. Paul, N., Hammond, R. B., Hunter, T. N., Edmondson, M., Maxwell, L., Biggs, S., Polyhedron, 89, 129141 (2015).
4. Short, R. J., Hand, R. J., Hyatt, N. C., Mobus, G., J. Nucl. Mater., 340, 179186 (2005).
5. Hand, R. J., Short, R. J., Morgan, S., Hyatt, N. C., Mobus, G., Lee, W.E., Molybdenum in glasses containing vitrified nuclear waste, ESG Proceedings, 2004.
6. Nicoleau, E., Schuller, S., Angeli, F., Charpentier, T., Jollivet, P., Le Gac, A., Fournier, M., Mesbah, A., Vasconcelos, F., J. Non-Cryst. Solids, 427, 120133 (2015).
7. Short, R., Turner, E., Dunnett, B., Riley, A., Mater. Res. Soc. Symp. Proc., 1107, 261267 (2008).
8. ASTM, “ASTM C965–81: Measuring viscosity of glass above the softening point,” 1981.
9. Dunnett, B. F., Gribble, N. R., Riley, A. D. and Steele, C. J., Mater. Res. Soc. Symp. Proc., 1193, 291298 (2009).
10. ASTM, “ASTM C1285–02: Standard Test Methods for Determining Chemical Durability of Nuclear, Hazardous, and Mixed Waste Glasses and Multiphase Glass Ceramics: The Product Consistency Test (PCT),” 2002.
11. Henry, N., Deniard, P., Jobica, S., Breca, R., Fillet, C., Bart, F., Grandjean, A., Pinet, O., J. Non-Cryst. Solids, 333, 199205 (2004).
12. Curti, E., Crovisier, J. L., Morvan, G., Karpoff, A. M., Appl. Geochem. 21, 11521168 (2006).
13. Harrison, M. T., Procedia Materials Science 7, 186192 (2014).
14. Rose, P. B., Ojovan, M. L., Hyatt, N. C. and Lee, W. E., Mater. Res. Soc. Symp. Proc., 824, 321326 (2008)

Keywords

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed