Investigation of Mineral Phase Transformation Technology Followed by Magnetic Separation for Recovery of Iron Values from Red Mud

Abstract

Experiments were conducted to investigate the mineral phase transformation technology of high-iron red mud, effectively extracting valuable iron minerals and reducing the hazards associated with red mud stockpiling and storage. A magnetic concentrate with an iron grade of 55.84% and recovery of 93.75% could be obtained at a roasting temperature of 560 °C, roasting time of 15 min, CO concentration of 20% and total gas flow of 500 mL/min. A combination of XRD and SEM-EDS analysis was employed to evaluate the phase transformation during the roasting process. ToF-SIMS analysis was applied to assess the occurrence state of various elements during the roasting of red mud.