Separação de ganga grosseira de minério de ferro através da flotação em leito fluidizado

Abstract

In the iron ore industry, reverse flotation is widely applied for particles smaller than 150 µm. Among the different types of flotation machines, mechanical cells and column cells are the most commonly used for iron ore flotation. In recent decades, innovative equipment that combines features of both cells and columns, as well as other separation technologies, has been developed and implemented in the mineral industry. This study aimed to evaluate the performance of the HydroFloat®, in the concentration of iron ore. This technology combines flotation with gravity separation through the use of a fluidized bed, which reduces turbulence in the cell and favors the formation of bubble-particle aggregates, thereby enhancing the flotation of particles larger than 150 µm. Two circuits were evaluated: one for pre-concentration and another to produce a final concentrate. The results showed that in the pre-concentration circuit, final tailings with iron grades between 5% and 12% and iron recoveries of up to 85.8% were obtained. The cleaner circuit produced concentrates with SiO₂ grades below 1.18% and iron grades above 67%, with metallurgical recovery exceeding 89%. In both circuits, it was possible to float quartz containing particles larger than 300 µm.