Iron ore reverse flotation has been the main concentration process applied in iron ore processing plants since the 1970s. The performance of this process has been strongly affected by the control of the previous desliming stages. The presence of ultrafine particles promotes selectivity losses in the flotation circuits, in addition to a significant increase in the consumption of chemical reagents and pumping energy. The removal of ultrafine particles promotes metal losses, the need for additional dewatering steps, difficulties in handling and stacking together with flotation waste. This study focuses on investigating the feasibility of replacing desliming with high intensity vertical magnetic concentrators (VPHGMS). Pilot tests were carried out with this type of magnetic concentrator followed by flotation, the results show an increase in metal recovery of 4% when compared to the traditional desliming and flotation circuit, drastic possibility of reducing energy, chemical reagents and foot print and potential to reduce capex and opex by 22% and 24%, respectively, for new projects.
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