复吹转炉双渣脱磷工艺实践

为解决帘线钢因磷偏析而造成的拧股断裂，根据现有的设备及生产组织情况，在中天120 t转炉上进行双渣工艺试验，通过对加料制度、顶枪操作、底吹等工艺制度进行研究，分析前期倒渣温度、碱度、FeO等对脱磷影响。结果表明，前期倒渣温度控制在1 320～1 400 ℃、炉渣碱度控制在1.8～2.0的工艺控制下，转炉终点脱磷率达到92.8%，平均出钢磷质量分数由0.011%降低至0.008 5%，平均终点碳质量分数由0.13%提高至0.205%。

Practice of double- slag dephosphorization technology for combined blown converter

In order to resolve the strand break caused by P segregation of cord steel and according to the existing equipment and production organization, the double- slag dephosphorization technology test of 120 t converter was conducted, the feeding system, the oxygen operation and the bottom blowing operation of the BOF steelmaking process were studied and the influences of semi steel temperature, basicity, oxide on dephosphorization were analyzed. The test results showed the optimal process condition for dephosphorization was the end of dephosphorization rate increased to 92.8% on the condition of the deslagging temperature of 1 320- 1 400 ℃ and the slag basicity of 1.8- 2.0 in the early stage of converter. At the same time, the average tapping P mass fraction decreased from 0.011% to 0.008 5%, and the average endpoint C mass fraction increased from 0.13% to 0.205%.