Effects of MgO/Al2O3 and CaO/SiO2 ratios on viscosity of high titanium-bearing blast furnace slag

The effects of MgO/Al2O3 and CaO/SiO2 ratios on the viscosity, break-point temperature, and viscous activation energy of a high titanium-bearing slag were studied. The results showed that both the viscosity and the break-point temperature of the slag decreased with the MgO/Al2O3 ratio increasing from 0.50 to 0.65, the viscous activation energy decreased gradually, and the thermal stability became better. In addition, with an increase in CaO/SiO2 ratio from 1.12 to 1.22, the main viscous units in the slag depolymerized and the viscosity of slag decreased. However, the break-point temperature of slag showed an increasing tendency. The viscous activation energy decreased gradually and the thermal stability became better. The basic phase in the experimental high titanium-bearing slag was pyroxene, and its amount increased with increasing the MgO/Al2O3 ratio while decreased with increasing the CaO/SiO2 ratio.