Effects of heating rate,quartz particle size,viscosity, and form of glass additives on high‐level waste melter feed volume expansion |
| |
| Authors: | SeungMin Lee Bradley J. VanderVeer Pavel Hrma Zachary J. Hilliard Jayven S. Heilman‐Moore Charles C. Bonham Richard Pokorny Derek R. Dixon Michael J. Schweiger Albert A. Kruger |
| |
| Affiliation: | 1. Pacific Northwest National Laboratory, Richland, Washington;2. Laboratory of Inorganic Materials, Joint Workplace of the University of Chemistry and Technology and the Institute of Rock Structure and Mechanics of the ASCR, Prague 8, Czech Republic;3. U.S. Department of Energy, Office of River Protection, Richland, Washington |
| |
| Abstract: | Nuclear waste can be vitrified by mixing it with glass‐forming and ‐modifying additives. The resulting feed is charged into an electric glass melter. To comprehend melting behavior of a high‐alumina melter feed, we monitored the volume expansion of pellets in response to heating at different heating rates. The feeds were prepared with different particle sizes of quartz (the major additive component) and with varied silica‐to‐fluxes ratio to investigate the glass melt viscosity effects. Also, we used additional melter feeds with additives premelted into glass frit. The volume of pellets was nearly constant at temperatures <600°C. After a short period of volume shrinkage at ~600°C‐700°C, foam generation produced massive volume expansion. The low heat conductivity of foam hinders the transfer of heat from molten glass to the reacting feed. The extent of foaming increased with faster heating and higher melt viscosity, and decreased with increasing size of quartz particles and fritting of the additives. Volume expansion data are needed for the mathematical modeling of the cold cap. |
| |
| Keywords: | cold cap frit glass‐forming and ‐modifying chemicals heating rate high‐level waste quartz particle size viscosity |
|
|
