酸性球团还原过程中微观结构变化研究  

Research on microstructure change of acid pellets during reduction

作　　者：杨广庆[1] 国宏伟[2] 王春苗[3] 刘卫星[3] 

机构地区：[1]河北联合大学冶金与能源学院,河北唐山063009 [2]苏州大学沙钢钢铁学院,江苏苏州215021 [3]河北联合大学轻工学院,河北唐山063000

出　　处：《烧结球团》2015年第2期20-24,共5页Sintering and Pelletizing

基　　金：河北省科技计划项目(13214104);国家自然科学基金资助项目(51204013)

摘　　要：在实验室模拟高炉条件下研究球团还原过程,采用X射线衍射仪(XRD)测定球团在不同还原温度下的物相组成,通过光学显微镜和扫描电镜(SEM)观察球团还原过程中微观结构的变化。研究结果表明:球团在还原过程中出现分层现象,由低温下外层磁铁矿-核心赤铁矿逐渐转变为高温下外层金属铁-核心浮士体;球团还原停滞现象首先由生成的渣膜包裹铁氧化物颗粒,引起还原速率降低,之后生成密实金属铁壳阻碍还原气体进入球团内部,进一步减慢还原速率。The acid pellet reduction process under the simulated condition of blast furnace was studied,the material phasecomposition of pellets under different reduction temperature was investigated by means of XRD, and the mierostructure of pelletsduring reduction process was observed by the optical microscope and SEM. The research results show that, different layers appearin the process of pellet reduction, the outer layer of magnetite-inner core of hematite at low temperature gradually is transformedinto outer layer of metallic iron-inner core of wtistite;The phenomenon of pellet reduction retardation is as follows, firstly the gen-erated slag film wraps up the iron oxide particles, causing the decrease of reduction rate, and then the generated dense metal ironshell prevents the reducing gas from entering pellets inside, slowing down the reduction rate further.

关 键 词：酸性球团 微观结构 物相组成 还原停滞 

分 类 号：TF046.6[冶金工程—冶金物理化学]