Research on the Effect of Limestone Slagging and Steelmaking in Converter on Silicon Gasification of Hot Metal
The influence of limestone addition process on silicon gasification of molten iron was studied through industrial experiments,and analyzed from four aspects:limestone addition amount,addition timing,addition batch,and gun position control.The results show that the silicon gasification rate of molten iron increases with the increase of limestone addition.When the limestone addition is higher than 6 tons,the silicon gasification rate of molten iron is about 15%.The silicon gasification rate of molten iron is less than 3%when limestone is input before smelting.The silicon gasification rate is 11.5%when F1(blowing stage)is input,and the highest is 14.7%when silicon manganese oxidation stage is input.The silicon gasification rate of molten iron is 2.5%when input in the early decarbonization stage.When limestone is divided into two inputs,the silicon gasification rate of molten iron is the highest,reaching 13.4%.By using the"high-low-high-low"gun position control method,the silicon gasification rate of molten iron is the highest,at 14.5%.However,this gun position is prone to oxygen gun nodulation and furnace mouth accumulation during smelting.Using the"high-low-high-high-low"gun position control method can not only ensure a high silicon gasification rate(14.1%),but also solve the problems of oxygen gun nodulation and furnace mouth accumulation.