Performance evaluation of a laboratory floatex density separator and its comparison with a spiral concentrator

Two different samples were collected from the Beneficiation Plant (BP) for detailed studies. Sample I and Sample II are the feeds to the spiral concentrator from an existing beneficiation circuit of BP at JSW steel with two different size fractions of −1 mm + 150 µm assaying 53.26% Fe, 13.94% SiO2, 6.88% Al2O3 and −150 µm assaying 51.7% Fe, 17.4% SiO2, 4.3% Al2O3, respectively. The samples consist of hematite as the major iron-bearing mineral and goethite as the minor iron-bearing mineral. In both sample it was found that interlocked phases of hematite with gangue minerals like koalinite, quartz etc in varying proportion. Laboratory trials have been carried out using FDS by varying the teeter water flow rate and bed height set point at constant feed flow rate. For the spiral concentrator the feed rate, slurry density and splitter position were varied. Test results indicated that FDS was highly selective in rejecting siliceous and aluminous gangue from iron ore compared to the spiral concentrator.