Modelling of Viscosity of Melts Containing Iron Oxide in Ternary Silicate Systems

Abstract

The motivation of this work is to show that the structural model, which was initially used to estimate the thermodynamic properties of binary silicate systems, can be also used to estimate the viscosity of binary and ternary silicate melts in terms of temperature and composition. The model links the viscosity to the internal structure of melts through the concentration of the oxygen bridges present in the slag. A previously proposed structural thermodynamic model was used to calculate the content of oxygen bridges. The viscosity model requires only three parameters to obtain a good agreement between experimental and calculated data for the SiO 2 −FeO binary system and for the SiO 2 −CaO−FeO, SiO 2 −MgO−FeO and SiO 2 −MnO−FeO ternary systems. The viscosity of ternary systems was calculated with the model while assuming a linear function of the parameters from binary systems; however, the content of the oxygen bridges was calculated using the thermodynamic model for ternary systems.

Viskositas: Viscosity Prediction of Multicomponent Chemical Systems

“…SiO2 increases the viscosity of SiO2-FeO [53], SiO2-Al2O3 [62] and CaO-Fe2O3 [68] chemical systems when added, TiO2 increases the viscosity of CaO-SiO2 and CaO-Al2O3-based mold flux [69]. ZrO2 does not have much influence on viscosity [59].…”

“…With the dissociation in the chemical species MO, there is a reaction between the M 2+ ions that weaken the chain between Si-O-Si. MgO decreases the viscosity of chemical systems SiO2-CaO-Al2O3-MnO-MgO-K2O [49], FeO decreases the viscosity of chemical systems CaO-SiO2-Al2O3-MgO-P2O5 [50], CaO and MgO decay the viscosity of chemical systems CaO-MgO-SiO2-Al2O3 [51] and CaO-SiO2-Al2O3-B2O3-Na2O-TiO2-MgO-Li2O-MnO-ZrO2 [52], MnO in binary systems SiO2-MnO [53] and the addition of NiO decreases the viscosity of chemical systems SiO2-Al2O3-Fe2O3-CaO-MgO-TiO2-SO3-K2O-Na2O-P2O5 [54] in fully liquid physical systems. The addition of MO chemical species can cause an increase in viscosity in chemical systems when linked to the precipitation of solid phases, thus increasing their viscosity by the non-Newtonian behavior indicated by the Roscoe-Einstein equation [55] (Equation 11).…”