提高淮钢转炉终点温度命中率的工艺优化

Process optimization for improving hit rate of BOF end-point temperature in Huaigang Works

为了解决转炉终点温度命中率低、造渣料消耗高的问题,对淮钢100 t转炉的冶炼工艺进行研究。主要措施包括氧枪喷头参数的选取、过程枪位的确定、造渣料的加入时机和底吹工艺模式的优化。根据工作氧压优化氧枪喷头参数,采用＂低-高-低＂枪位模式,总体枪位相比旧工艺提升0.1 m;控制加入造渣料的数量,石灰用量为27 kg/t（钢）,轻烧白云石用量为12 kg/t（钢）;把转炉前期底吹流量由0.02提高到0.1 m3/（t·min）。现场试验结果表明,终点温度命中率提高39.87%,脱磷率提高2.58%,总造渣料减少约8.5 kg/t（钢）,冶炼时间缩短0.53 min。通过岩相分析,新工艺整体渣中游离氧化钙控制在5%左右,比旧工艺成分更加稳定。

To solve the problems of low BOF end-point temperature hit rate and high consumption of slag materials,the smelting process was optimized for a 100 t converter in Huaigang. The main measures include the selection of oxygen lance nozzle parameters,the determination of lance height in smelting process,addition time of slag material and mode optimization of bottom blowing process. The oxygen lance parameters were optimized according to actual working oxygen pressure. The low-high-low lance height model was used and total lance height increased 0.1 m compared with original process. The amount of slag materials was controlled,and the lime and light burned dolomite were 27 and 12 kg/t（steel）. The bottom blowing rate of converter increased from 0.02 to 0.1 m3/（t · min）. The industrial test results show that temperature hit rate of BOF end-point was improved by 39.87%,the dephosphorization rate was improved by2.58%,the total slagging materials consumption was reduced by about 8.5 kg/t（steel）and the smelting time was shortened by 0.53 min. By means of petrographic analysis,the total free calcium oxide in the slag of the new process is controlled at about 5%,which is more stable than that of the old process.