300 t转炉IF钢低枪位低终点氧冶炼工艺实践

Process Practice of 300 t BOF Smelting with Low Lance Position and Low End-Point Oxygen for IF Steel

在脱磷理论分析基础上,采用低枪位冶炼和低终点氧出钢,增大出钢口直径和降低终点温度,并优化底吹工艺降低碳氧积,取得了较好的脱磷效果。生产应用结果表明:采用增大出钢口和优化底吹工艺后,300 t转炉出钢时间缩短至5.1 min,缩短了1.9 min;IF钢终点温度降低至1 670.6℃,降低了17.4℃;碳氧积降低至13.3,降低了8.9;终点氧降低至422.5×10^(-6)。在铁水磷升高0.010%,枪位降低30 cm,终点氧降低153.3×10^(-6)的条件下,工艺优化后的平均终点磷含量为0.012 4%,能够满足转炉冶炼IF钢对脱磷效果的要求。

On the basis of theoretical analysis of dephosphorization,by using low lance position smelting and low endpoint oxygen tapping,increasing diameter of tapping hole and reducing the end-point temperature,and optimizing bottom blowing process to reduce the carbon-oxygen equilibrium,a better dephosphorization effect is achieved.The results of production and application show that after adopting large tapping hole and optimizing bottom blowing process,the tapping time of 300 t converter is shortened to 5.1 min,shortened by 1.9 min;the end-point temperature of IF steel is reduced to1670.6℃,reduced by 17.4℃;the carbon-oxygen product is reduced to 13.3,reduced by 8.9;the end-point oxygen is reduced to 422.5×10-6.Under the condition of increase of hot metal phosphorus by 0.010%,decrease of lance position by 30 cm and decrease of end-point oxygen by 153.3×10-6,the average end-point phosphorus content after process optimization is reduced to 0.0124%,which can meet the requirements of dephosphorization effect of IF steel smelting in converter.