氧化铝含量对高炉熔渣析晶行为的影响

高炉熔渣直接纤维化过程中,晶相析出会使熔渣的黏度增加、流动性降低,从而影响矿渣棉纤维质量.熔渣的化学组成会对其析晶行为产生重要影响.采用FactSage热力学模拟结合X射线衍射分析(XRD)、场发射电子显微镜分析(FESEM)、能谱分析(EDS)和热丝法(HTT)等研究方法,探析了 Al2O3质量分数(11％～19％)...

Influence of alumina content on crystallization behavior of molten blast furnace slag

The crystallization of molten blast furnace (BF) slag can increase its viscosity and reduce its liquidity, which can affect the quality of slag fibers during BF slag direct fibrosis process. The chemical composition is one of the main factor which impacts on the crystallization behavior of molten BF slag. FactSage thermodynamics simulation, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS) and hot thermocouple technique (HTT) were performed to investigate the effect of Al₂O₃ mass fraction (11%-19%)on the crystallization behavior of BF slag during cooling process. It was found that the main crystallized minerals of BF slag were melilite, anorthite, clinopyroxene and wollastonite during the cooling process. The critical cooling rates of BF slag with Al₂O₃ mass fraction of 11%, 13%, 15% and 17% were 60, 50, 15, 15 ℃/min, respectively. The crystallization of molten BF slag was not observed when Al₂O₃ mass fraction was increased to 19% and the cooling rate was higher than 3 ℃/min. Increase of Al₂O₃ content decreased the initial crystallization temperature and the critical cooling rate of BF slag, which would benefit the production of slag fiber using BF slag. This work aims at investigating the influence of Al₂O₃ content on the crystallization behavior of molten BF slag, which would lay a theoretical and experimental foundation for the direct production of slag fiber using molten BF slag.