基于微观结构解析的转炉熔渣泡沫化评估

Foaming Evaluation of Converter Slag Based on Microstructure Analysis

摘要: 为明晰化学成分变化对转炉渣泡沫化程度的影响机制，采用Raman光谱对CaO-SiO₂-Fe_xO系转炉渣的微观结构进行解析，结合转炉渣黏度与表面张力的检测结果，应用泡沫化模型来评估转炉渣的发泡性能。结果表明，熔渣中存在Q⁰_Si、Q¹_Si、Q²_Si、Q³_Si、Q⁴_Si五种硅氧四面体结构和[FeO₄]-四面体及[FeO₆]-八面体结构，随着碱度和Fe_xO含量的升高，高聚合度四面体结构向低聚合度转变，熔渣非桥氧数增多，聚合程度降低；黏度随Fe_xO含量降低而增大，随碱度的升高而减小，表面张力随Fe_xO含量降低而减小，随碱度的升高而增大，这与熔渣微观结构转变行为相符。依据泡沫化模型计算结果表明，转炉渣本身的发泡性随Fe_xO含量降低而增大，随碱度的升高而减小；另外，探讨了转炉渣发泡性、物理性质和微观结构间的关系。

Abstract: To clarify the influence mechanism of chemical composition on the foaming of converter slag, the microstructure of CaO-SiO₂-Fe_xO slag system was analyzed by Raman spectroscopy and the viscosity and surface tension of converter slag. Finally, the foamability of the converter slag was eval-uated by the foaming model. The results showed that Q⁰_Si, Q¹_Si, Q²_Si, Q³_Si, [FeO₄]-tetrahedron and [FeO₆]-octahedron existed in the molten slag. With the increase of basicity and Fe_xO content, the tetrahedral structure with a high degree of polymerization transforms to the tetrahedral structure with a low degree of polymerization, the non-bridging oxygen number increases, and the degree of polymerization decreases. The physical property test results showed that the viscosity increased with the decrease of Fe_xO content and decreased with the increase of basicity; the surface tension decreased with the decrease of Fe_xO content and increased with the increase of basicity. According to the calculation results of foaming model, the foamability of converter slag increased with the decrease of Fe_xO content, and decreased with the increase of basicity. In addition, the relationship among the foaming of converter slag, physical properties and microstructure was discussed.