菱铁矿在煤基直接还原条件下的转化过程  

Transformation process of siderite under the conditions of coal-based direct reduction

作　　者：闫树芳[1] 孙体昌[1] 许言[1] 

机构地区：[1]北京科技大学土木与环境工程学院,北京100083

出　　处：《北京科技大学学报》2012年第7期755-760,共6页Journal of University of Science and Technology Beijing

摘　　要：为研究菱铁矿在强还原气氛下加热过程中铁矿物的转化过程和规律,采用热重分析、X射线衍射和扫描电镜等手段研究了嘉峪关某菱铁矿石在煤基直接还原过程中菱铁矿的热行为和不同条件下焙烧产物中铁矿物的存在形式等.结果表明,菱铁矿在煤基直接还原条件下转化为金属铁的历程为FeCO3→Fe3O4→FeO→Fe.转化过程分为菱铁矿分解和铁氧化物还原两个阶段;热分解阶段在556.6℃时基本结束,最终产物为Fe3O4;铁氧化物的还原阶段在556.6℃以后、1200℃时完全结束,最终产物为金属铁.In order to research the transformation process and transformation path of siderite during heating process in strong reduction atmosphere, the thermal behaviors of siderite from Jiayuguan Mine in Gansu Province of China under coal-based direct reduc- tion conditions were studied by thermogravimetry, X-ray diffraction （XRD） , scanning electron microscopy （SEM） , etc. The existence form of iron minerals in roasting products in different roasting conditions was observed. It is shown that the path of transforming siderite into iron is FeCO3→Fe3Og→FeO→Fe. The transformation process includes two stages： siderite decomposition and iron oxide reduction. The thermal decomposition stage of siderite finishes at 556.6 ℃ , and the product is Fe3 04 ; the reduction of iron oxides comes out after 556.6 ℃ and finishes completely at 1 200 ℃ , and the final product is metallic iron.

关 键 词：菱铁矿 煤 直接还原 铁 焙烧 

分 类 号：TD925.7[矿业工程—选矿]