Numerical simulation of iron ore fines reduction using COREX gas in Z-path moving-fluidized bed

A two-dimensional CFD model was developed for pre-reduction of iron ore fines using a Z-path moving-fiuidized bed. The proposed model was solved using an integration of PHOENICS and FLUENT. Simulation results of cold state including pressure drop per perforated plate, gas flow patterns and solid flow patterns were compared to experimental results and the agreement between them was good. The model was applied to predict the performance of the reactor for gaseous reduction of iron ore fines using purified COREX export gas as reductant. It is indicated that under the simulation conditions gas temperature drop is about 700 K, utilization rates of the gas reduction potential of CO and H2 are about 38% and 26%, respectively, and the reduction fraction of the ore fines reaches 75%. This means that the reactor has the advantages of excellent gas-solid heat transfer and high reduction potential utilization. The reactor realizes a gradient utilization of the heat and reduction potential of the reducing gas.