稀土尾矿对CaO-SiO₂-Fe₂O₃-稀土尾矿渣系脱磷行为的影响

Effect of Rare Earth Tailings on Dephosphorization Behavior in CaO-SiO₂-Fe₂O₃-Rare Earth Tailings Slag System

摘要: 基于稀土尾矿可以作为炼钢氧化脱磷助熔剂的作用，论文借助于Factsage软件计算了稀土尾矿对CaO-SiO₂-Fe₂O₃-稀土尾矿渣系熔化温度和粘度的影响；通过实验研究了1390℃时，CaO-SiO₂-Fe₂O₃-稀土尾矿渣系对普通铁水氧化脱磷的影响。结果表明：随着w(稀土尾矿)的逐渐增大，CaO-SiO₂-Fe₂O₃-稀土尾矿渣系的熔化温度先逐渐降低后略有升高，当w(稀土尾矿) = 15.5%~23%时，CaO-SiO₂-Fe₂O₃-稀土尾矿渣系熔化温度可以控制在1350℃以下；w(稀土尾矿)对CaO-SiO₂-Fe₂O₃-稀土尾矿渣系的粘度影响不大。随着w(稀土尾矿)的逐渐增大，CaO-SiO₂-Fe₂O₃-稀土尾矿渣系的脱磷率先增大后减小，当w(稀土尾矿)控制在15.5%~21.5%时，CaO-SiO₂-Fe₂O₃-稀土尾矿渣系的脱磷率达到90%以上。

Abstract: Based on the role of rare earth tailings as flux for oxidation dephosphorization in steelmaking process, this paper calculates the effects of rare earth tailings on the melting point and viscosity of CaO-SiO₂-Fe₂O₃-rare earth tailings slag system with the help of Factsage software. The effect of CaO-SiO₂-Fe₂O₃-rare earth tailings slag system on oxidation and dephosphorization of ordinary hot metal at 1390˚C was studied experimentally. The results show that with the gradual in-crease of w(rare earth tailings), the melting temperature of CaO-SiO₂-Fe₂O₃-rare earth tailings slag system firstly decreases gradually and then increases slightly. When w(rare earth tailings) = 15.5~23%, the melting temperature of CaO-SiO₂-Fe₂O₃-rare earth tailings slag system can be controlled below 1350˚C. But w(rare earth tailings) has little effect on the viscosity of CaO-SiO₂-Fe₂O₃-rare earth tailings slag system. As w(rare earth tailings) gradually increases, the dephosphorization rate of CaO-SiO₂-Fe₂O₃-rare earth tailings slag system first increases and then decreases. When w(rare earth tailings) is controlled between 15.5% and 21.5%, the dephosphorization rate of CaO-SiO₂-Fe₂O₃-rare earth tailings slag system reaches over 90%.