转炉冶炼高磷高带渣量铁液脱磷工艺研究

Process of Dephosphorization of Molten Iron with High Phosphorus and Slag in Converter Smelting

国内某钢厂在炼钢时采用铁液直上工艺,铁液磷含量高,带渣严重,脱磷效果差。通过对转炉冶炼高磷高带渣量铁液的脱磷工艺研究,结合其它企业双渣法脱磷工艺实践经验,优化了冶炼工艺。结果表明,将第一次倒渣时间推迟到4~6 min,第一次倒渣和终点温度控制在1 400~1 430℃和1 600~1 650℃,炉渣碱度控制在2.0~2.5和2.5~3.0,渣中Fe O质量分数控制在15%~20%和20%~25%,取得了良好脱磷效果。转炉整体脱磷率达到80%~95%,较原来工艺明显提高。

For one domestic steel plant, the molten iron was poured into converter directly. The molten iron was higher phosphorus content, and the amount of slag, and the dephosphorization effect was poor. Based on the study of dephosphorization and combined with the practice of double-slag process in other enterprises, the smelting process of converter with high phosphorus and high slag content was optimized. The results show that the time of the first deslaging is delayed 4 to 6 min, the first pour the slag and the temperature control in the 1 400-1 400℃ and 1 600-1 650℃, slag alkalinity is controlled at 2.0-2.5 and 2.5-3.0, the mass fraction of FeO in slag is controlled at 15%-20% and 20%-25%, Good dephosphorization effect is obtained. The dephosphorization rate of converter reaches 80%-95%, which is obviously higher than that of the original process.