Optimum Study Of Slag Splashing Technology In The Converter At Long-steel

In this paper,Lining life of 4 # BOF at the Shaanxi Long-men Steel and Iron Group Limited Company(Long-steel) is analyzed and studyed.By studying the slag composition and the properties of the process of slag splashing in laboratory,and the effects of TFe and MgO on the molten properties of slag and the mechanism of slag splashing,the main problem of influencing the results of slag splashing has been found.By studying the process of slag splashing for Long-steel to obtain:The main problems affecting the lining life are the molten iron ingredient fluctuating in a big way,the low quantity of MgO and the high quantity of FeO in slag.At the same time,normative practice and unreasonable parameters including the position of oxygen gun and the suitable amount of slag should also be considered especially.The optimal process parameters for the Long-steel 50t converter is the N₂ pressure for 0.9-1.1Mpa,and the flow for the 9000-11000m³.The lance position is in 1200 mm,when the furnace bottom rises,the lance position declines 900 mm.The average time for Splashing slag controls in 2.5min.The reasonable slag amount is 2.5～3.5t.On the other hand,the slag amount to stay is 60～80 kg each heat.Based on the above studying,splashing slag has been making a research at the Long-steel.Since slag splashing is carried out,it sovled the problem of the unstable antegrade production by the premium and non-plan maintenance of the furnace frequently.At present,the life of converter lining has already reached to 15,000 heats, the productivity reached 87%.In addition,through building the physical model for studying the selective slag splashing to obtain:Lance position LP2 is more appropriate for slag splashing than LP1.Plugging one nozzle from LP2 further improves splashing properties.At low lance distance(0.16-0.18m),the amount of splashing increased on charge pad and trunnion areas and decreased on slag hole side.If the lance height is the only variable for splashing procedure,splashes on slag hole side are difficult to avoid when protection for trunnion and charge pad areas is desired.