| Sinter as the main raw materials into the blast furnace, its quality has a great influence for blast furnace iron-making. In recent years, due to the benefit of iron and steel industry declining seriously and facing fierce competition, it is necessary to introduce some low-cost iron ore for cost reduction and resource conversation, what makes the sinter quality instability and intensity difference. Mineral composition and microstructure of the sinter are the fundamental factors which affect the quality of sinter. The article is taking samples from different types of sintering machine of the iron and steel enterprise. First observe and analyze the sample microstructure, then test the metallurgical properties of sinter samples further and judge the quality of sinter based on mineral composition and microstructure. The cohesive action and effect between them are understood by studying the combination of bonding and iron ore facies to explore whether there is potential factors causing sinter break even pulverization. Calcium ferrite in sinter is in good reducibility and high strength, according to this characteristic, through the configuration of different proportion of sintering raw material to design orthogonal experiment for sintering based on the material before adding into the furnace in iron and steel enterprises. Thereby analyze the factors influence on calcium ferrite generation in sinter, which provides the theoretical foundation for the iron and steel enterprise production.Due to complex calcium ferrite?SFCA? in the sinter with good reducibility and high intensity, the study configures with different ratio of sintered materials by designing orthogonal experiment which based on the sintering raw materials of Nangang, then sintering in the high temperature furnace after tableting and sampling. Study the generation and main influence factors of calcium ferrite by microscopic observation to the homemade sintering samples, providing theoretical basis for the optimization of sinter burdening of Nangang.With the improvement of binary basicity and ternary basicity, reducibility and low temperature reduction pulverization property of the sinter has a certain degree of improvement. Its structure makes change from porphyritic texture of poor quality to mixed corrosion structure of a better quality and the calcium ferrite generation of sinter increases simultaneously. The metallurgical properties of sinter reduce gradually with increasing of SiO2, but the sinter of calcium silicate bonding phase is in rising. The metallurgical property of sinter with increase of Al2O3 shows increasing trend after then decreases and poor strength of vitreous content increases gradually.The analysis of the sintering produced samples finds the content of calcium ferrite increases with increasing of sintered samples basicity and the content of calcium ferrite decreases with increasing of sintering time. The content of calcium ferrite shows increasing trend after then decreases as the increase of sintering temperature and the content of SiO2 and Al2O3. The sinter basicity on the effect of calcium ferrite generation is the largest, the second is sintering temperature and the influence of Al2O3 is minimal through range analysis. Analysis shows that the amount of calcium ferrite produces in the basicity of 2.4, the temperature of 1260 degrees, heat preservation time of 10 minutes, SiO2 content of 5.5% and Al2O3 content of 1.9%. In the paper, experiment study expects to provide theoretical guidance for optimizing the sinter quality. |
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