转炉留渣双渣工艺两阶段脱磷对比

Comparison of two-stage dephosphorization during remaining slag-double slag process in converter

为了获得两阶段脱磷的关键工艺参数,通过统计100t转炉留渣双渣工艺生产数据,比较了脱磷及脱碳阶段的脱磷有利条件,研究结果表明,两阶段脱磷条件对脱磷效果的影响规律存在显著差异,脱磷阶段炉渣碱度为1.8~2.2、Fe2O3质量分数为23%~28%、钢液温度为1 350~1 400℃时,可获得最优的脱磷效果;脱碳阶段炉渣碱度为3.2~5.2、Fe2O3质量分数为18%~30%、钢液温度为1 600~1 700℃时,提高炉渣碱度及Fe2O3质量分数或降低钢液温度可获得更优的脱磷效果;脱磷、脱碳阶段都没有达到热力学平衡,但脱磷阶段与热力学平衡差距更大,脱碳阶段更接近热力学上的平衡。

In order to obtain the key process parameters of two-stage dephosphorization,the production data during remaining slag-double slag process for 100 tconverter were collected.The favorable conditions of dephosphorization and decarburization were compared.The results show that there was a significant difference in the change rules of phosphorus removal with the changing conditions between these two stages.The optimal dephosphorization effect can be obtained in dephosphorization stage when the basicity of slag was in the range of 1.8~2.2,the mass percent of Fe2O3 was 23%-28%and molten steel temperature changed from 1 350 to 1 400℃.Better dephosphorization effect can be obtained by increasing the basicity of slag and Fe2O3 mass percent,or decreasing the temperature of molten steel in decarburization stage when the basicity of slag was in the range of 3.2-5.2,the mass percent of Fe2O3 was 18%-30%and the molten steel temperature changed from 1 600 to 1 700℃.Thermodynamic equilibrium state have not been reached during dephosphorization stage and decarbonization stage.It was further to be thermodynamic equilibrium state in dephosphorization stage but closer to that in decarbonization stage.