IRON RECOVERY FROM RED MUD BY REDUCTION ROASTING-MAGNETIC SEPARATION

摘要

This work provided an effective method for comprehensiveutilization of red mud, which mainly focused on the first stepof recovering iron from a high iron content red mud byreduction roasting-magnetic separation. During the reduction,iron oxides were reduced to metallic iron with the aid ofsodium sulfate and sodium carbonate. Effects of the dosages ofsodium sulfate and sodium carbonate, roasting temperature androasting time on the metallization ratio of iron of roastedproduct, total iron grade and iron recovery of magneticconcentrate were primarily investigated. In the presence of 6%Na_2SO_4, 6% Na_2CO_3 and optimal reduction roasting-magneticseparation conditions: roasting temperature of 1050°C,roasting time of 60 min, magnetic separation feed fineness of90% passing 74 μm and magnetic field intensity of 0.1 T, amagnetic concentrate containing 90.12% iron with ironrecovery of 94.95% was obtained from a red mud containing48.23% total iron, 7.71% Al_2O_3 and 7.69% SiO_2.