High-Efficiency Nanobubble Coal Flotation

Abstract

The high efficiency of a froth flotation process is limited to a narrow particle size range. Nanobubbles integrated into a specially designed flotation column expanded the particle size range for effective froth flotation as a result of increased probabilities of particle-bubble collision and attachment and reduced probability of detachment. Results show that combustible recovery of a −150 μm coal sample increased by 5%–50% in the presence of nanobubbles. Nanobubble also increased the kinetic flotation rate constant by more than 40%. Other major advantages of the nanobubble flotation process include lower collector dosage since nanobubbles are produced selectively on hydrophobic particle surface.