Effect of Nepheline Syenite on Iron Losses in Slags during Desulphurization of Hot Metal

The effect of injection of nepheline syenite (NS) together with CaC2 and C on the iron losses in form of metal droplets in a slag during desulphurization of hot metal is investigated in industrial trials. The characteristics of different metal droplets (such as morphology, number, size and composition) in slags of trials without and with injection of a NS are investigated using SEM. All metal droplets in the slag are classified into three groups according to morphology: Type A-spherical/oval; Type B-spherical/irregular; Type C-irregular. It is found that the addition of NS influences the compositions of hot metal, slag and metal droplets in slag. As a result, the amount (area fraction) and size of metal droplets decreased for Type A and B and increased significantly for Type C droplets present in the slag.