Considering the heat effect of chemical reaction in microscale
a model coupling heat and mass transfer with chemical reaction was developed to simulate the kinetic behavior of fine ferrous oxide.Finite Volume Method(FEM)with fully implicit technique were applied for solving the governing parabolic equations.The reduction degrees of fine iron oxide at different conditions of temperature
initial gas concentration and particle size were calculated with the model.The model was validated by comparing with experimental results in the literature.The gas concentration profile developing inside the ferrous oxide particle and the time of complete reduction were given.Simulation results show that the diffusion of gas inside the particle influences the reduction rate extremely
and that the time for full reduction of iron oxide with particle size of 200~300 μm is from 450 s to 1 400 s.
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references
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