ABSTRACT
A new approach has been developed for the prediction of coal slag viscosity in the case of phase separation below the temperature of critical viscosity. This phenomenon causes deviations from ideal viscosity as compared to unseparated slag of the same bulk composition. We discuss the cause of viscosity deviation in slags and introduce a new method of viscosity calculation that accounts for the structural changes in the slag as phase separation begins. It is assumed that the viscosity depends on the degree of polymerization of the slag and the dispersion of nuclei. Above the critical temperature, viscosity is calculated from both Arrhenian and configurational entropy models. Both models are modified as the base/acid ratio crosses a value of 0.2.
