转炉终渣氧化性对脱磷的影响

Effect of Oxidability of Final Slag in Converter on Dephosphorization

为了研究唐山建龙60 t转炉中高碳钢脱磷的氧化性控制原则,对转炉冶炼终点C-O、Fe-O平衡进行了分析和计算,并对钢液中溶解氧平衡的磷含量和渣中（Fe O）平衡的磷含量进行了计算。结果表明：转炉冶炼终点渣氧化性决定钢液中的磷含量,当终点钢液溶解氧在0.03%到0.045%之间时,[P]-[O]平衡磷含量是（Fe O）-[P]平衡磷含量的21~38倍;终渣（Fe O）含量大于13%,可实现终点磷含量小于0.015%。对于终点碳含量大于0.1%的钢种进行工业实验,通过加料和枪位调整提高终渣氧化性,终点平均磷含量为0.013%,脱磷率提高8%。

Control principles of oxidability for Tangshan Jianlong 60 t converter slag middle （high）-carbon steel dephosphorization process was studied. The C-O, Fe-O reaction equilibrium of endpoint converter smelting were analyzed and calculated, the factors influencing the endpoint oxygen content of BOF were analyzed. The phosphorus content in liquid steel determined by the equilibrium of oxygen and phosphorus content in slag equilibrium of （FeO） were calculated. The results show that phosphorus content is decided by oxidability in molten steel. When dissolved oxygen content is between 0.03% and 0.045%, content of phosphorus determined by [P]-[O] equilibrium is 21-38 times of that determined by （FeO）-[P] equilibrium. Phosphorus content less than 0.015% can be achieved in endpoint of converter if the final slag （FeO） content greater than 13%. Industry experimental of endpoint carbon content 〉0.1% steel results show that the endpoint of an average phosphorus content was 0.013%, dcphosphorization rate increased 8% by adjusting the converter charging and oxygen lance position.