PNNL

Abstract

Using existing data on corrosion of partially crystallized, simulated, high-level waste glasses, coefficients were introduced to evaluate the cumulative influence of secondary effects, such as residual stresses or concentration gradients on product consistency test response. As compared to predictions based solely on residual glass composition effects, the results showed that cristobalite, eucryptite, and nepheline had a higher-than-predicted impact on glass corrosion, while the effects of baddeleyite, hematite, calcium-zirconium silicate, and zircon were close to those predicted. The effects of acmite and lithium silicate were opposite to those expected based on their compositions. The analysis revealed important limitations of the databases currently available. Better understanding of corrosion phenomena will require quantitative composition data, microscopic characterization of pristine and corroded surfaces, and long-term tests with glass coupons or monoliths.