The mining of iron ore is a high volume low margin business because the value of this commodity isrnsignificantly lower than that of base metals. The main metallurgical challenges in most of the iron orernprojects proposed for treatment nowadays have been in finding the optimum flowsheet for therntreatment of magnetite ores, mixed magnetite-hematite ores and even ores that have banded ironstonernformations (BIF). The associated plant designs incorporate very high capacity milling systems torngrind the ore down prior to magnetic separation and in being highly capital intensive requiresrnsubstantial investment in mega processing plants with associated infrastructure to mill down the runof-rnmine ore to the desired treatment size for upgrading.rnTo minimise the cost of infrastructure, better beneficiation techniques and technologies are beingrnsought to assist in reducing upfront ROM feed to allow for reduction in overall treatment plantrnfootprint necessary in extracting the desired downstream product. This paper discusses suchrnbeneficiation techniques and advancement in technologies for the upgrading of coarse and fine ironrnore utilising dense media separation (DMS), jigging, wet magnetic separation, dry magneticrnseparation, flotation and x-ray processing.rnAnother group of iron ore projects involve the mining of hematite ore below the water table. Often thernmined ore is wet and sticky. This combination requires high capacity processing of feed materialrnutilising large scrubbers or attritioning units to effectively remove the slimes component present in thernfeedstock. The fines removed, usually below 1 mm, are then discarded in large tailings storagernfacilities. Approaches to recovering the saleable material contained within these fines will also berninvestigated in this paper. This not only implies possible reduction in slimes discard footprint, but alsornholds potential benefit in augmenting overall yield and recovery of hematite product.
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