东北大学学报:自然科学版 ›› 2019, Vol. 40 ›› Issue (2): 261-266.DOI: 10.12068/j.issn.1005-3026.2019.02.021

• 资源与土木工程 • 上一篇    下一篇

CO/CO2气氛下赤铁矿向磁铁矿的流化床还原转变

余建文, 韩跃新, 高鹏, 李艳军   

  1. (东北大学 资源与土木工程学院, 辽宁 沈阳110819)
  • 收稿日期:2017-09-06 修回日期:2017-09-06 出版日期:2019-02-15 发布日期:2019-02-12
  • 通讯作者: 余建文
  • 作者简介:余建文(1988-),男, 江西余干人, 东北大学博士后研究人员; 韩跃新 (1961-),男, 内蒙古赤峰人,东北大学教授,博士生导师.
  • 基金资助:
    国家自然科学基金资助项目(51734005,51674064,51674065); 中国博士后科学基金资助项目(2018M631812); 东北大学博士后科研基金资助项目(20180316).

Reductive Transformation of Hematite to Magnetite with CO/CO2 Under Fluidized Bed Conditions

YU Jian-wen, HAN Yue-xin, GAO Peng, LI Yan-jun   

  1. School of Resources & Civil Engineering, Northeastern University, Shenyang 110819, China.
  • Received:2017-09-06 Revised:2017-09-06 Online:2019-02-15 Published:2019-02-12
  • Contact: HAN Yue-xin
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摘要: 采用纯矿物试验、等温还原法和微观结构分析法研究了赤铁矿向磁铁矿流化床还原转变行为及动力学.动力学研究表明,以20%CO和80%CO2(质量分数)混合气体为还原流化剂、微型流化床为反应器,在还原温度为773~873K时,赤铁矿向磁铁矿的选择性还原转化受磁铁矿晶核的形成和一维生长A3/2模型控制,反应的表观活化能ΔEa为49.64kJ/mol,指前因子A为6.55s-1.BET比表面分析及扫描电镜测试结果表明,新生磁铁矿晶核呈致密针状结构,且长度不一;随着反应的进行,针状结构晶核增多并聚集形成多孔状的磁铁矿颗粒.

关键词: 赤铁矿, 悬浮磁化焙烧, 磁铁矿, 转变行为, 反应动力学

Abstract: The reductive transformation behavior and kinetics of hematite to magnetite under fluidized bed conditions were studied by single mineral roasting test, isothermal reduction method and microstructure analysis. The results of reaction kinetics show that the selective reduction of hematite to magnetite with reductive fluidizing agent of 20wt%CO-80wt%CO2 in a micro-fluidized bed reactor at 773-873K is controlled by formation of magnetite crystal nucleus and one-dimensional growth(A3/2 model), the apparent activation energy ΔEa of the reaction is 49.64kJ/mol and the pre-exponential factor A is 6.55s-1. The results of BET specific surface analysis and scanning electron microscopy measurement show that the fresh magnetite nucleus are dense needle-like structure with different lengths, and that as the reaction proceeds, the magnetite nucleus with the needle-like structure increases and aggregates to form porous magnetite particles.

Key words: hematite, fluidized magnetization roasting, magnetite, transformation behavior, reaction kinetics

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