Investigation on the Kinetics of Iron Ore Fines Reduction by CO in a Micro-fluidized Bed

AbstractKinetics of Brazilian iron ore fines reduction was investigated in a micro fluidized bed, a newly developed kinetics analyzer for gas-solid reactions, where the effects of external and internal diffusion were significantly reduced by modifying the operation conditions. The reducing gas was a mixture of CO and N2 and the temperature ranged from 973K to 1123K. The experimental data was analyzed with respect to the reduction mechanism of iron oxides, and the feasibility of the segment treatment on the experimental data was discussed. The kinetics parameters were determined by the iso-reduction degree method as well as models matching method, and compared with available data in the literature. Moreover, a reduction model for iron ore fines was hence established in terms of piecewise differential rate function, and the reduction stage FexO→Fe is considered as the most likely limit step during the reduction of iron ore fines