STUDIES ON PELLETIZATION, INDURATION AND REDUCTION OF MILL SCALE

An account of studies carried out on pelletization, drying, firing and hydrogen reduction of mill scale generated at Egyptian Iron and Steel Co. is presented. The mill scale contained a high proportion of wustite, magnetite, and metallic iron was pelletized in a disc pelletizer, using water as a binder material. The studies on pelletization was conducted by varying disc slope/angle (45-70°), residence time (5-12 min.), speed of pelletizer (13-17 rpm), feed size (-50 to 270 mesh) and amount of binder (6-11%) with an aim to prepare pellets with optimum properties. Green pellets were subjected to physical studies on drying (100-400 degreeC) and firing (500-1300 degreeC) for different periods of time prior to hydrogen reduction at 1000 °C. At each stage pellets were evaluated with respect to their compressive strength and average drop number. The changes in the properties at different stages of processing are explained with the support of chemical analysis and microstructure.