Reoxidation and carburization study of reduced iron ore pellets

Abstract

The influence of carburization on the reoxidation of commercial iron ore pellets was studied. The pellets were H₂-reduced up to 88 % and then carburized in H₂/CO/CO₂ gas mixture, for 0, 12, 18, 25 and 32 min, at 700, 800, 900 and 1000°C. After the reduction-carburization process, the pellets were reoxidized at 250, 300, 350 and 400°C. It was found out that the higher reduction temperature, the lower was the reoxidation degree. This effect was stronger at the reoxidation temperatures of 250 and 300°C. The presence of iron carbide (Fe₃C) was more notorious when the reduction was carried out at 700 and 800°C, and the carburization time was increased. Finally, it was observed that the higher the reoxidation temperature, the higher was the reoxidation degree.