MgO对高碱度高铝烧结矿的影响  

Influence of MgO on high basicity high alumina sinter

作　　者：易正明[1,2] 覃佳卓 姜志伟[1] 秦庆伟[1] 邵慧君 杜东 YI Zheng-ming;QIN Jia-zhuo;JIANG Zhi-wei;QIN Qing-wei;SHAO Hui-jun;DU Dong(Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China;National provincial Joint Engineering Research Center of High Temperature Materials and Lining Technology,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China;Coking Division,Shuicheng Iron and Steel Group Co.,Ltd.,Liupanshui 553000.Guizhou,China)

机构地区：[1]武汉科技大学钢铁冶金与资源利用省部共建教育部重点实验室,湖北武汉430081 [2]武汉科技大学高温材料与炉衬技术国家地方联合工程研究中心,湖北武汉430081 [3]水城钢铁集团有限公司铁焦事业部,贵州六盘水553000

出　　处：《钢铁》2021年第2期50-56,92,共8页Iron and Steel

基　　金：国家自然科学基金资助项目(51604199)。

摘　　要：随着钢铁企业高铝铁矿粉使用比例的提高,带来了高炉炉渣黏度增大、渣铁分离困难等一系列问题。采用烧结杯试验,研究了MgO含量增加对高碱度高铝烧结矿经济技术指标、冷强度和冶金性能的影响,采用Nova400NanoSEM型场发射扫描电子显微镜分析了烧结矿微观结构。试验结果表明,高碱度高铝烧结矿中MgO质量分数从1.72%提高到2.49%时,垂直烧结速度降低4.38mm/min,利用系数降低0.51t/(m^(2)·h),低温还原粉化指数增加6.7%;当烧结矿中MgO质量分数为2.11%时,转鼓指数和还原度最高,分别达到61.93%和86.39%;Mg^(2+)主要固溶在磁铁矿晶格中并替代Fe^(2+),替代的质量分数最高达3.64%,生成的含镁磁铁矿抑制烧结矿降温过程中由Fe_(3)O_(4)→Fe_(2)O_(3)氧化过程的相变,减少了二次赤铁矿的生成,有利于改善烧结矿的低温还原粉化性能。研究结果可以为改善高碱度高铝烧结矿性能和提高炉渣流动性提供理论指导和参考依据。The increase of the proportion of high Al2O3 content iron ore fine in iron and steel enterprises has brought about a series of problems such as the increase of the viscosity of blast furnace slag and the difficulty of the separation of slag and iron.The effect of increasing MgO content on the technical and economic index,the cold strength,and metallurgical properties of high basicity and high alumina sinter was studied through the sinter pot test.Nova 400 NanoSEM field emission scanning electron microscope was used to analyze the microstructure of the sinter.The experimental results show that when the mass percent of MgO in the sinter with high alkalinity and high aluminum increases from 1.72% to 2.49%,the vertical sintering speed decreases by 4.38 mm/min,the utilization coefficient decreases by 0.51 t/(m^(2)·h),and the low-temperature reduction degradation index increases by 6.7%.When the mass percent of MgO in the sinter is 2.11%,the drum index and the reducibility index are the highest,reaching 61.93%and 86.39%respectively.Mg^(2+) is mainly solid dissolved in the magnetite lattice and replaces Fe^(2+),and the mass fraction of the replacement reaches up to 3.64%.The generated magnesium-containing magnetite inhibits the phase transition from Fe_(3)O_(4) to Fe_(2)O_(3) oxidation process in the sinter cooling process,which reduces the generation of secondary hematite and is conducive to improving the low-temperature reduction degradation performance of the sinter.The research results can provide theoretical guidance and reference for improving the properties of high-basicity and high-alumina sinter and adjusting the fluidity of blast furnace slag.

关 键 词：高铝烧结矿 高碱度烧结矿 MGO 冶金性能 微观结构 

分 类 号：TF046.4[冶金工程—冶金物理化学]