Reaction Mechanism and Thermodynamics of Segregation Roasting of Iron Oxide

This paper presents the reduction mechanism of iron recovery from pure ferric oxide by the segregation roasting-magnetic separation process both from the chemical reaction and physical phenomena point of view. In segregation roasting process, coal is used as the reducing agent and calcium chloride as chlorinating agent. Segregation roasting of iron oxide has been studied at different temperatures from 800 to 1000°C varying the chloride and carbon percentages. The same experimental conditions have been adopted to recover iron from mill scale by the process of segregation roasting. By segregation roasting, iron oxide is reduced by a combination of chlorination, volatilization and hydrogen reduction. Elucidation of the reaction mechanism of segregation process is being attempted in this present study. Characterization of the segregated iron particles recovered after magnetic separation both from ferric oxide and mill scale is studied by electron probe microscopy analyzer.