Coke Combustion Rate with the Presence of Hematite in Quasi-particles

The coke combustion rate in the iron ore sintering process is one of the most important factors affecting the quality and productivity of iron ore sintering. The purpose of this study was to investigate the combustion rate of coke in the presence of hematite to simulate the actual conditions in a sinter machine. The experimental samples were prepared by mixing coke powder with hematite powder. Experiments were carried out under an air or N₂ atmospheres at 1 073, 1 173 and 1 273 K. From the results of the reaction curves, the coke combustion rates were analyzed using an unreacted-core model with one reaction interface. From the kinetic analysis, it was found that the reaction rate constant k_c (m/s) and effective diffusion coefficient D_e (m²/s) of the sample were both affected by the experimental temperature. Furthermore, the D_e value of the sample was affected by the amount of coke. However, the k_c of the sample was not affected by this.