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-Al2O3-SiO2 slags after adding Na2O or K2O, and investigated the influences of Na2O and K2O on the slag viscosity under given temperatures and heat quantities. It was found that the slag viscosity decreases with the addition of Na2O and tends to increase with K2O additions at the same temperature. The heat capacity of the slag increases, while the enthalpy change decreases obviously with the increasing addition of Na2O or K2O. Under the constant heat quantity, an increase in content of Na2O or K2O of the slag leads to an appreciable increase in slag temperature, whereas the viscosity decreases significantly. Besides, the Na2O or K2O additions also help to stabilize the slag fluidity and lower energy consumption of blast furnace.