Recovery of iron from red mud-rice husk briquettes by microwave roasting
An innovative method to recover iron from reduction-roasted red mud-rice husk briquettes using microwave bulk-phase heating was proposed.The effects of the main process,parameters,such as feeding mode,biomass dosage,roasting temperature and time on iron recovery were investigated.The results show that,under the optimized conditions of rice husk to red mud mass ratio of 3,roasting temperature of 1000 ℃ and roasting time of 20 min,the iron concentrate with iron grade of 60.1%and recovery rate of 86.3%is obtained.The mechanism of the reduction process of iron oxides in red mud was analyzed and investigated using X-ray diffraction and X-ray fluorescence spectroscopy.The iron-containing minerals in red mud are reduced to magnetic substances,such as Fe and FeO.
microwave bulk-phase heatingreduction-roastingred mud-rice huskbriquettesrecovery of iron