Melting of glass batch: Model for multiple overlapping gas-evolving reactions

In this study, we present a model for the kinetics of multiple overlapping reactions. Mathematical representation of the kinetics of gas-evolving reactions is crucial for the modeling of the feed-to-glass conversion in a waste-glass melter. The model simulates multiple gas-evolving reactions that occur during heating of a high-alumina high-level waste melter feed. To obtain satisfactory kinetic parameters, we employed Kissinger's method combined with least-squares analysis. The nth-order reaction kinetics with variable reaction order sufficed for obtaining excellent agreement with measured thermogravimetric analysis data.

► We model kinetics of multiple overlapping glass-melting gas-evolving reactions.
► Three kinetic coefficients plus reaction weight suffice for agreement with data.
► Kissinger method allows avoiding problems with the compensation effect.
► Maximum temperature shift by overlapping does not affect use of Kissinger method.
► The model is adequate for implementing in an advanced waste-glass melter model.