ABSTRACT

Mineral flotation is a wet concentration operation that has a differentiating effect dependent on the surface properties of the minerals. Water quality is integral to the phosphate ore flotation, since the presence of certain ions in the solution can compromise the effectiveness of the operation. The objective of this study was to compare the effectiveness of phosphate ore flotation (dispersed air) before and after effluent treatment using coagulation, flocculation and dissolved air flotation (DAF) techniques. The mineral flotation tests were performed for new water (NW) and three effluents tailing dams (TD), simulated effluent with high concentrations of calcium and magnesium ions (SE) and simulated effluent after DAF treatment (SE_DAF). The simulated effluent underwent two stages of aggregation followed by DAF for cation removal. The results showed that the proposed technique removed 91.6% of magnesium and 66.4% of calcium from the original simulated effluent (SE). The SE_DAF presented better average values of mass recovery, content, and recovery of P₂O₅, confirming the effectiveness of the removing ions suggested as deleterious for mineral flotation. The flotation performance of the DAF-treated effluent was comparable to that of new water. This study underscores the significance of water quality management in optimizing mineral flotation processes.

Keywords:
Dissolved air flotation; Ca²⁺ and Mg²⁺ ions; Mineral flotation; Phosphate ore; Water reuse.