Application of Optical Basicity for Estimation of Viscosity of SiO2-CaO-MgO-Al2O3 System
A viscosity model based on NPL model with the corrected optical basicity is proposed for quaternary SiO2-CaO-MgO-Al2O3 slag system in the present work. The modified Arrhenius type of equation for temperature dependence of slag viscosity is employed. By means of fitting measured viscosity values for slags with basicity from 0.4 to 1.0 and temperature from 1593 to 1803 K, model parameters are optimized against values of optical basicity, which represents both the structure of molten slags and cationic effects. The relationship between model parameters and optical basicity, which is different from NPL model, is obtained. The present model is applied to estimate viscosity values of slag in SiO2-CaO-MgO-Al2O3 system. The comparison between estimated and measured values shows good agreement with a mean deviation of 12%. It proves fully that the present model can express the temperature dependence and composition dependence of viscosity.