A discussion of magnetic separation techniques for concentrating ilmenite and chromite ores

Figure 1 depicts the basic magnetic separation technologies now available in the marketplace in terms of field intensities and modes of processing. LIMS and scalper magnets are not detailed in this paper. The selection of magnetic separation technology depends on many processing factors, including particle size, and the specific assemblage of minerals and grades as well as their corresponding magnetic susceptibility. Additionally, production and marketing factors must also be considered, i.e. is ilmenite production linked to rutile and zircon production, is the ilmenite saleable or is it waste, are further downstream processes necessary to bring products to a marketable quality, etc.? Prior to discussion of separator selection in specific circumstances, it is beneficial to understand the general rationale for placing different types of magnetic separators in mineral sands applications.