磁化焙烧冷却过程中磁铁矿氧化动力学

Oxidation Kinetics of Magnetite During the Cooling Process of Magnetization Roasting

针对磁化焙烧冷却过程开展了研究,考察了磁铁矿氧化反应分数和反应速率的变化规律,并采用模型匹配法进行了氧化动力学分析.结果表明:磁化焙烧冷却过程中,氧化温度对反应分数和反应速率均有着显著的影响;相同氧化时间下,反应分数和反应速率随氧化温度的升高而增加;不同氧化温度下,反应分数和反应速率随反应时间变化呈现出相同的变化规律;磁铁矿氧化过程动力学机理函数为n=4的AvramiErofee方程,氧化反应的表观活化能为135. 2 k J·mol,指前因子为6. 19×1010min-1.

The cooling process of magnetization roasting has been investigated.The variation of magnetite oxidation reaction fraction and rate was observed,and the oxidation kinetics was analyzed using model matching method.The results indicated that oxidation temperature had a significant effect on the reaction fraction and rate.At the same oxidation time,the reaction fraction and rate increased as temperature increasing.The curves of reaction fraction and rate under different temperatures presented the similar variation with increasing reaction time.The mechanism function of isothermal oxidation of magnetite was determined to be Avrami-Erofee equation with n=4.The apparent activation energy and pre-exponential factor were 135.2 kJ·mol and 6.19×10^10 min^-1,respectively.