Novel approach to studying influences of Na2O and K2O additions on viscosity and thermodynamic properties of BF slags

The present work calculated the heat capacity, enthalpy change, and slag temperature of CaO–MgO–Al O –SiO slags after adding Na O or K O, and investigated the influences of Na O and K O on the slag viscosity under given temperatures and heat quantities. It was found that the slag viscosity decreases with the addition of Na O and tends to increase with K O additions at the same temperature. The heat capacity of the slag increases, while the enthalpy change decreases obviously with the increasing addition of Na O or K O. Under the constant heat quantity, an increase in content of Na O or K O of the slag leads to an appreciable increase in slag temperature, whereas the viscosity decreases significantly. Besides, the Na O or K O additions also help to stabilize the slag fluidity and lower energy consumption of blast furnace