CaO-FeO-SiO2-Al2O3/Na2O/TiO2渣系与碳饱和铁水间磷分配行为

 为了研究Al2O3、Na2O和TiO2作为铁水预处理渣的助熔剂对铁水预处理脱磷的影响，借助FactSage热力学软件绘制了CaO-FeO-SiO2渣系1 573 K液相区。随着Al2O3和Na2O质量分数的增加，该渣系液相区明显扩大，TiO2对渣系液相区影响不大。实验室研究采用纯铁箔替代碳饱和铁水进行热力学平衡试验，间接测定了1 573 K时铁水预处理脱磷渣与碳饱和铁水间的平衡磷分配比。结果表明，渣铁磷分配比随渣中Al2O3和TiO2质量分数的增加而减小，TiO2对磷分配比的影响相对较小；渣铁磷分配比随渣中Na2O质量分数和碱度的增加而增加，Na2O可显著提高渣的脱磷能力；渣铁磷分配比随渣中FeO质量分数的增加先增加后减小，最合适的FeO质量分数为35%～40%。

Distribution behavior of phosphorus between CaO-FeO-SiO2- Al2O3/Na2O/TiO2 slags and carbon-saturated iron

The influence of Al2O3,Na2O and TiO2 on dephosphorization as fusing agent in liquid iron pretreatment slag was studied. The liquid region of CaO-FeO-SiO2 slag at 1573 K was drew using FactSage. It indicated that with the ad-dition of Al2O3 and Na2O,the area of liquid region of CaO-FeO-SiO2 slag at 1573 K was obviously enlarged,while TiO2 had little influence. In order to measure the phosphorus distribution ratios between dephosphorization slags for liquid iron pretreatment and carbon-saturated liquid iron at 1573 K,the carbon-saturated liquid iron was replaced with pure iron foil in this study. The results show that the phosphorus distribution ratio decreased with the increase of Al2O3 and TiO2 in slag. The influence of TiO2 on phosphorus distribution ratio was relatively weak. The phosphorus distribution ra-tio increased with the increase of Na2O content. The phosphorus distribution ratio firstly increased with the increase of FeO concentration,then shown a decreasing behavior. The most suitable concentration of FeO lied between 35%and 40%.