SPHC钢LF精炼过程的抑制回硅与脱硫研究

生产SPHC钢在LF处理脱硫过程中不能抑制回硅.根据热力学理论推导出降硅参数A/S和脱硫参数C/A,应用共存理论作用浓度模型,在试验渣系成分范围内计算CaO、SiO2、Al2O3的活度求解A/S和C/A,探讨了它们与w(CaO)/w(Al2O3)、w(CaO)/w(SiO2)的关系.分析结果认为,控制w(CaO)/w(Al2O3)、w(CaO)/w(SiO2)在合适的范围内,可以有效地分别或同时抑制回硅和脱硫.与试验结果对照得知,A/S和C/A分别与LF渣系的抑制回硅和脱硫能力相对应,根据A/S和C/A进行控制是可行的.

Study on Silicon Increase and Desulphurization During LF Treatment of SPHC Steel

It is very difficult to inhibit silicon pick-up during desulfurization in LF treatment of SPHC steel.According to thermodynamic analysis,the silicon content decrease parameter A/S and desulphurization parameter C/A are put forward.The activities of CaO,SiO2 and Al2O3 are calculated with the model of mass action concentration of co-existence theory for experimental slags.Thus the parameters A/S and C/A are calculated and the relationship between w(CaO)/w(Al2O3),w(CaO)/w(SiO2) and the parameters A/S,C/A are discussed.Firstly,if the w(CaO)/w(Al2O3),w(CaO)/w(SiO2) are controlled within a rational range,it is possible to inhibit silicon increase and desulphurize by refining slag individually or simultaneously.Additionally,it is known that A/S can denote the refining slag's ability of decreasing the silicon pick-up from slag and C/A can denote slag's ability of desulphurization from experiment results.Finally,it is proved that it's feasible to control the slag composition according to A/S and C/A for achieving low silicon content or low sulphur or for both of them of molten steel.