Reduction Behavior of Packed Bed of Sinter Reduced by CO-CO2-H2-H2O-N2 Gas

To mitigate CO2 emission from a blast furnace, the use of H-2 as a reducing agent is considered to be a prominent method. Reduction of iron ore was reported to be improved by H-2 addition. In the present research, reduction in a sinter-packed bed by CO and H-2 was carried out under various oxygen partial pressures, and the influence of reduction atmosphere on the reaction behavior was investigated. It was confirmed that the reduction rates were higher when using H-2/H2O and CO/CO2/H-2/H2O mixtures than when using a CO/CO2 gas mixture. The reaction rate constant for iron ore reduction was determined from the experimental result using a numerical model. The influence of the water-gas shift reaction on the reduction rate was analyzed by comparing the results obtained using the numerical model and those in the experiments. Moreover, the longitudinal distribution of the reaction rate in the packed bed was analyzed to examine the influence of the water-gas shift reaction.