Effects of Quartz Particle Size and Sucrose Addition on Melting Behavior of a Melter Feed for High-Level Waste Glass

The behavior of melter feed (a mixture of nuclear waste and glassformingadditives) during waste-glass processing has a significantimpact on the rate of the vitrification process. We studied theeffects of silica particle size and sucrose addition on the volumetricexpansion (foaming) of a high-alumina feed and the rate ofdissolution of silica particles in feed samples heated at 5°C/minup to 1,200°C. The initial size of quartz particles in feed rangedfrom 5 to 195 mm. The fraction of the sucrose added ranged from0 to 0.20 g per g glass. Extensive foaming occurred only in feedswith 5-mm quartz particles; particles ≥150 mm formed clusters.Particles of 5 mm completely dissolved by 900°C whereas particles≥150 mm did not fully dissolve even when the temperaturereached 1,200°C. Sucrose addition had virtually zero impact onboth foaming and the dissolution of silica particles.