1 State Key Laboratory of Advanced Metallurgy and School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China 2 The Key Laboratory of Chemical Metallurgy Engineering of Liaoning Province and School of Materials and Metallurgy, University of Science and Technology Liaoning, Anshan 114051, Liaoning, China
Primary slag formation behavior during reduction process of SFCA-I and SFCA
1 State Key Laboratory of Advanced Metallurgy and School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China 2 The Key Laboratory of Chemical Metallurgy Engineering of Liaoning Province and School of Materials and Metallurgy, University of Science and Technology Liaoning, Anshan 114051, Liaoning, China
摘要 Because the formation behavior of primary slag which decomposed from complex calcium ferrite (SFCA-I and SFCA) is not quite clear, the migration behavior of CaO and Al2O3 derived from high basicity or high alumina sinter is always worth studying. The reducibility of three representative sinter samples and the formation behavior of primary slag during reduction process were investigated via X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy characterization. The results show that the reducibility of high basicity sinter is superior to that of high alumina sinter. Minerals with poor reducibility like hercynite and brownmillerite and with large-grained particles like free alumina and silica form in sinters with basicity of 2.4 and Al2O3 content of 4 wt.%, respectively. The appearance of these minerals can well explain the reduction stagnation phenomenon occurring in these sinter samples. The migration behavior of CaO and Al2O3 during slag formation process is different. CaO can easily combine with SiO2 to form silicate phase or firstly form calcium-rich ferro-aluminate solid solution and then transform to silicate phase, while Al2O3 firstly combines with CaO and FeO to form solid solution and then, gradually combines with SiO2 to form calcium aluminum silicate phase.
Abstract:Because the formation behavior of primary slag which decomposed from complex calcium ferrite (SFCA-I and SFCA) is not quite clear, the migration behavior of CaO and Al2O3 derived from high basicity or high alumina sinter is always worth studying. The reducibility of three representative sinter samples and the formation behavior of primary slag during reduction process were investigated via X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy characterization. The results show that the reducibility of high basicity sinter is superior to that of high alumina sinter. Minerals with poor reducibility like hercynite and brownmillerite and with large-grained particles like free alumina and silica form in sinters with basicity of 2.4 and Al2O3 content of 4 wt.%, respectively. The appearance of these minerals can well explain the reduction stagnation phenomenon occurring in these sinter samples. The migration behavior of CaO and Al2O3 during slag formation process is different. CaO can easily combine with SiO2 to form silicate phase or firstly form calcium-rich ferro-aluminate solid solution and then transform to silicate phase, while Al2O3 firstly combines with CaO and FeO to form solid solution and then, gradually combines with SiO2 to form calcium aluminum silicate phase.
Fan-jian Meng,Chang-yu Sun,Ting-le Li, et al. Primary slag formation behavior during reduction process of SFCA-I and SFCA[J]. Journal of Iron and Steel Research International, 2022, 29(11): 1748-1759.