1980 Volume 66 Issue 13 Pages 1985-1994
In order to clarify the effect of the pressure on the hydrogen reduction of iron oxide pellets by a laboratory moving bed, the experiments were performed under the conditions of pressure at 0.117, 0.304 and 0.507 MPa by using the apparatus which was 0.13 m in internal diameter of reaction tube and 2.0 m in availble height. The results obtained were analysed by the one dimentional mathematical model considering both heat and material transfer.
Final fractional reduction, gas utilization and production rate of reduced iron were increased by pressure increase and pressure drop in the moving bed were decreased. The rate parameters in the reduction rate equation were determined by the stepwise reduction experiments of a single iron oxide pellet and overall heat transfer coefficient of the moving bed was obtained by the heat transfer experiments of a fixed bed. The distribution of calculated process variables such as gas temperature, fractional reduction and mol fraction of hydrogen are well agreed with the observed data at 0.117 MPa. However, both calculated distributions and observed data at high pressure were not in agreement sufficiently. Furthermore, observed pressure drops in the moving bed were represented by the Ergun's equation.
