Performance Evaluation of Magnetic Field Intensity on Iron ore slimes

Abstract

Iron ore industries facing a problem of huge slime generation, dumping causing not only environmental issues but prime natural resources are wasted also. A detailed characterization followed by beneficiation of two different slimes of iron ores generated during processing of ROM and dump fines was studied using hydrocyclone followed by wet high intensity magnetic separator to recover the valuables and as these are already in fine state can be converted to pellets for DRI or blast furnace application. Slime sample-I, generated from ROM through scrubbing and sizing for coarse lump as well as fines and classification assayed 59.25% Fe, 5.14% Al 2 O 3, 4.11% SiO 2 , and 4.83% LOI. The Slime sample-II generated from dump fines after classification assayed 58.4% Fe, 5.27% Al 2 O 3, 4.67% SiO 2 , and 5.22% LOI. Although the slimes chemical composition is different, XRD analysis shows that hematite and goethite are major phase whereas gibbsite, kaolinite and quartz are minor gangue minerals phases. One interesting aspect of the observation is that Slime –I indicated higher percentage of goethite compared to low grade slime –II. Multi-stage processing has been done at different magnetic field intensity for two different slimes. Detailed characterization of product sample has been carried out to study the performance of field intensity on separation efficiency.