Microbubble augmented flotation of ultrafine chalcopyrite from quartz mixtures

Abstract

The impact of microbubbles on flotation efficiency has been studied for ultrafine ( < 12 μm) chalcopyrite recovery from chalcopyrite/quartz artificial mixtures using laboratory pneumomechanical and column flotation cells. The findings show that significant enhancement in the efficiency of ultrafine minerals beneficiation is ensured by using the method known as combined microflotation based on simultaneous use of both coarse air bubbles (conventionally produced in flotation cells) and microbubbles generated by a standalone generator in the form of air in water microdispersion. Introduction of microbubbles at the dosage of 8–16 L per 1 kg of chalcopyrite before its treatment in a pneumomechanical flotation cell increased the flotation rate by several times. In the case of column flotation, introduction of microbubbles at the dosage of around 50 L per 1 kg of chalcopyrite following pulp treatment in a static mixer for 60 s before feeding it into the column cell increased the copper recovery by more than 50%. Increasing the treatment time of the pulp in the static mixer to 80 s led to gains in copper recovery by more than 60%, even in the absence of cell aeration by coarse air bubbles (turbulent microflotation regime).