机械力储能对石墨-磁铁矿体系碳热还原热力学的影响

分析了石墨和磁铁矿的机械活化能, 并就其对碳气化反应及磁铁矿碳热还原反应热力学的影响进行了理论探讨。研究结果表明, 石墨或磁铁矿的储能均可使磁铁矿碳热还原温度降低。磁铁矿的储能对还原热力学的影响方式是直接的, 而石墨的储能对还原热力学的影响是间接的: 石墨储能导致气化反应平衡常数增大, 从而间接影响磁铁矿的碳热还原热力学。另外, 磁铁矿的两个还原反应1/4Fe₃O₄+CO=3/4Fe+CO₂和Fe₃O₄+CO=3FeO+CO₂的转折温度随磁铁矿储能的增加而线性下降, 但不受石墨储能的影响。

Impact of Stored Energy Derived from Mechanical Activation on Thermodynamics of Carbothermic Reduction of Graphite-magnetite Mixture

The mechanically activated energy of graphite and magnetite and its effects on gasification of graphite and carbothermic reduction thermodynamics of magnetite were analyzed and discussed. The results show that the stored energy in either graphite or magnetite can lead to the decrease of magnetite reduction temperature. However, the stored energy in magnetite impacts the reduction thermodynamics directly, while the stored energy in graphite impacts the reduction thermodynamics indirectly, that is, the stored energy makes the equilibrium constant of gasification reaction increase, which has indirect impact on the carbothermic reduction thermodynamics of magnetite. In addition, the transition temperatures for two reduction reactions such as 1/4Fe₃O₄+CO=3/4Fe+CO₂ and Fe₃O₄+CO=3FeO+CO₂ decrease linearly with the increase of the stored energy in magnetite, but is not affected by the stored energy in graphite.