300 t转炉IF钢低枪位低终点氧冶炼工艺实践

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,300t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。

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

On the basis of theoretical analysis of dephosphorization, by using low lance position smelting and low end¬point 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 to 1670.6 T , reduced by 17.4 °C ；the carbon-oxygen product is reduced to 13.3 , reduced by 8.9; the end-point oxygen is reduced to 422.5 x 10. 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 x 10^-6,the average end-point phosphorus content after process optimization is reduced to 0.012 4% , which can meet the requirements of dephosphorization effect of IF steel smelting in converter.