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›› 2010, Vol. 10 ›› Issue (1): 127-132.

• 过程与工艺 • 上一篇    下一篇

Al-Si-Fe合金真空热法炼镁过程动力学

胡文鑫 刘建 冯乃祥 彭建平   

  1. 东北大学材料与冶金学院 东北大学材料与冶金学院 东北大学材料与冶金学院 东北大学材料与冶金学院
  • 收稿日期:2009-09-25 修回日期:2009-11-09 出版日期:2010-02-20 发布日期:2010-02-20
  • 通讯作者: 胡文鑫

Vacuum Thermal Reduction Kinetics of Calcined Dolomite with Al-Si-Fe Alloy

HU Wen-xin, LIU Jian, FENG Nai-xiang PENG Jian-ping   

  1. School of Materials and Metallurgy, Northeastern University School of Materials and Metallurgy, Northeastern University School of Materials and Metallurgy, Northeastern University School of Materials and Metallurgy, Northeastern University
  • Received:2009-09-25 Revised:2009-11-09 Online:2010-02-20 Published:2010-02-20
  • Contact: HU Wen-xin,

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摘要： 采用收缩未反应核模型研究Al-Si-Fe合金真空热还原煅后白云石制镁过程动力学，考察了制团压力、还原温度(T)和添加氟盐对镁还原率(R)的影响. 结果表明，在40~150 MPa内，制团压力越大，镁还原率越高；添加氟盐可加快还原反应速率，提高镁还原率. 确定了还原过程最佳工艺条件为：还原温度1413 K、还原时间(t) 120 min、真空度4 Pa、制团压力150 MPa、CaF2添加量3%. 在1373~1413 K内，还原过程为一级反应，由还原剂通过固体产物层的内扩散步骤控制，宏观动力学方程为1+2(1-R)-3(1-R)2/3=0.194exp(-8.38×103/T)t，表观活化能为69.7 kJ/mol.

关键词: Al-Si-Fe合金, 金属镁, 真空热还原, 动力学

Abstract: Vacuum thermal reduction kinetics of calcined dolomite with Al-Si-Fe alloy was studied using shrinking unreacted-core model. The effects of pellet forming pressure, reduction temperature (T), and villaumite on reduction rate (R) of calcined dolomite were investigated. The results show that within the pellet forming pressure from 40 to 150 MPa, the reduction rate is increased with increasing of the pressure. Villaumite can accelerate the reduction rate and then increase the reduction rate, and the optimal conditions are reduction temperature 1413 K, reduction time (t) 120 min, vacuity 4 Pa, pellet forming pressure 150 MPa and addition of CaF2 3%. The reduction process is the first order reaction and controlled by diffusion of reductant in solid product layer. The equation for the reduction kinetics is 1+2(1-R)-3(1-R)2/3=0.194exp(-8.38×103/T)t, and the apparent activation energy 69.7 kJ/mol.

Key words: Al-Si-Fe alloy, magnesium, vacuum thermal reduction, kinetics

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