基于FactSage的脱磷渣中MgO饱和溶解度计算

Calculation of saturated solubility of MgO in dephosphorization slag based on FactSage

利用Factsage热力学软件对高磷铁水(w[P]=0.5%)的脱磷平衡过程进行模拟计算,并根据渣系相图对计算结果进行理论分析。结果表明,温度一定的条件下,渣中MgO饱和溶解度(w(MgO)SS)受到Fe t O质量百分比和碱度等因素的综合影响:当碱度R<1.5时,w(MgO)SS随着Fe t O质量百分比的增加而减小;当1.5≤R<4.0时,w(MgO)SS先随着Fe t O质量百分比的增加先增大后减小,且当w(Fe t O)为40%左右时,w(MgO)SS达到最大值;当R≥4.0时,w(MgO)SS随着Fe t O质量百分比的增加而增加。另外,温度升高会促进渣对MgO的溶解,渣中w(MgO)SS有所增加。

The dephosphorization equilibrium process of high-phosphorus molten iron(w[P]=0.5%)was simulated by thermodynamic software FactSage,and the calculation results were theoretically analyzed according to the slag phase diagrams.The results show that under the condition of constant temperature,the saturated solubility of MgO in the slag(w(MgO)SS)is affected by the combination of Fe t O content and basicity.When the basicity R is smaller than 1.50,w(MgO)SS decreases with the increase of Fe t O content;when basicity R is within the range of 1.5~4.0,w(MgO)SS first increases and then decreases with the increase of Fe t O content,and w(MgO)SS reaches the maximum when the Fe t O content is around 40%.When the basicity R is no less than 4.0,w(MgO)SS increases as the Fe t O content increases.In addition,the rise of temperature promotes the dissolution of MgO in slag;in other words,w(MgO)SS in the slag increases accordingly.