基于转炉CaO-SiO_2-FeO-10%MgO渣系脱磷行为

Dephosphorization behavior of CaO-SiO_2-FeO-10%MgO slag in BOF melting process

基于CaO-SiO_2-FeO-10%MgO渣系,从热力学角度对渣钢界面的脱磷行为进行分析,归纳出磷分配比与钢液温度、碳质量分数以及炉渣成分间的表达式,并在此基础上绘制出了CaO-SiO_2-FeO-10%MgO渣系的等磷分配比线,同时分析了转炉终渣氧化性、碱度以及温度对磷分配比的影响情况。研究结果表明,转炉吹炼过程磷分配比是钢液温度、碳质量分数和炉渣成分的函数,通过与实际生产数据进行验证,发现其与实际结果吻合良好。基于该预测公式,在其他条件不变情况下,随着炉渣FeO质量分数增加,磷分配比LP先增加后减小,当终渣FeO质量分数为18%左右时达到最大值;随着终渣碱度的增加,渣钢间磷分配比增加,当终渣超过4.0时,磷分配比增加不再明显。

An expression among phosphorus partition ratio,slag composition,carbon content in steel and temperature is regressed based on thermodynamic analysis of the dephosphorization behavior of CaO-SiO_2-FeO-10%MgO slag system at the slag-steel interface,and the iso-phosphate partition ratio graph of the CaO-SiO_2-FeO-10%MgO slag system is depicted by regression expression,and the effect of Fe O content,basicity of slag and temperature in the endpoint of BOF smelting process on the phosphorus partition ratio is analyzed. The results show that phosphorus partition ratio is a function of temperature,carbon content and slag composition,which has been proved based on actual production data.According to the above equation,with the increasing of FeO content of slag,the distribution ratio LPof phosphorus between slag and steel first increases then decreases and reaches a maximum when FeO content is about 18%. With the increasing of basicity of slag,the distribution ratio LPof phosphorus between slag and steel increases and the increase amount is not obvious when the basicity of slag is over 4.0.