Low-Cost and Large-Scale Clean Steel Production Technology

As the market demand for clean steel increased,a number of new technologies for clean steel production have been developed in some domestic and foreign steelmaking plants.Based on the existing equipments and technical conditions in the No.1 steelmaking plant of Ansteel,a series of clean steel technologies have been integrated including single bay duplex-dephosphorization in steelmaking control technology,high efficiency desulfurization technology,the control technology for nitrogen content during the whole process,the control technology for hydrogen content in VD,and the systematic control technology for oxygen content.A series of process for all kinds of ultra-low phosphorus,ultra-low sulfur and relative low level of inclusions have been designed in clean steel production.This process include hot metal desulfurization and slag-off,single bay duplex-dephosphorization in BOF,molten steel slag-off,LF processing,VD processing,and continuous casting with protection,then a stable,low-cost and large-scale production process has been formed.Applying this integrative technology,the sum of 5 major elements including phosphorus,sulfur,oxygen,nitrogen,hydrogen is less than 80×10-6 in high alloy steel scale production,and the industrial applications for clean steel technology have been achieved.