EFFECTS OF PARTICLE-SIZE ON THE FUSION OF SODA LIME SILICATE GLASS CONTAINING NACL

The coupled effects of particle size and 1 wt% NaCl additions on the s equence of melting reactions in a multicomponent system (sand-soda ash -calcite-dolomite-feldspar) were studied using data from DTA, DTGA, an d XRD interactively. Glass batches varied in average particle size fro m 250 mum to finer than 45 mum. Milestone events in the fusion process of the coarse particle base glass were elucidated. The termination te mperature of the last significant reaction associated with CO2 release was 35-degrees-C lower in the fine particle size batch than with the coarsest batch. Liquid-phase formation at approximately 523-degrees-C in the batch with 1 wt% NaCl occurred to an increasingly sizable exten t with decreasing particle size. This contrasts with a similar effect at approximately 630-degrees-C for a comparable batch without NaCl via eutectic melting between soda ash and dolomite. Sodium chloride addit ions significantly enhanced dissolution or CaO relic.