富硼渣MgO-B2O3-SiO2-FeO体系表面张力计算

摘要

Based on the coexistence theory of ions and molecules of molten melt structure and Butler's equation,a thermodynamic model was developed to establish the surface tension of MgO-B2O3-SiO2-FeO system and its sub-system.The relationship between the composition and temperature and surface tension of molten slag was investigated.The results indicate that the calculated values for related systems show good agreements with the literature data,and the average error is about 11.85％.The surface tension of molten slag decreases with increasing the B2O3 content significantly in molten slag binary system.The surface tension value of pure oxide is related to the electrostatic potential of cations and the ion bond percentage in oxide.The surface tension in MgO-B2O3-SiO2-FeO system decreases significantly with increasing temperature and the B2O3 content,and increases with increasing the mass ratio of MgO to SiO2.While the B2O3 content is 17％-19％,the trends that surface tension varied with the FeO content,are changed.When the B2O3 content is low,surface tension of slag increases with the increase of the FeO content;when the B2O3 content is high,the surface tension decreases with the increase of the FeO content.%基于熔渣结构离子与分子共存理论和Butler方程建立MgO-B2O3-SiO2-FeO体系表面张力计算模型,计算该体系及其子体系的表面张力,考察熔渣组元和温度对表面张力的影响.研究结果表明:本模型计算的相关体系熔渣表面张力与文献实验值吻合较好,模型平均相对误差为11.85％.含B2O3体系熔渣中,B2O3组元能够显著降低熔渣表面张力,纯氧化物表面张力与形成氧化物的阳离子静电势及氧化物中离子键分数有关.MgO-B2O3-SiO2-FeO体系表面张力随B2O3含量增加和温度升高而显著降低,随着MgO/SiO2质量比的增加而逐渐增大;当B2O3质量分数为17％～19％时,表面张力随FeO含量的变化规律发生改变,当B2O3含量较低时,熔渣表面张力随着FeO含量的增加而增大,当B2O3含量较高时,表面张力随着FeO含量的增加而降低.