Effect of Mineral Particle Size on Froth Stability

Abstract

Mineral particles offer an added stability to three-phase froths, in addition to the stability imparted by frothers. The ability of particles to influence froth stability is particle size dependent. Knowledge of the quantitative effect of particle size on froth stability is essential for froth flotation model development and prediction.

This study investigated the extent to which discrete particle size fractions, as well as mixtures of particle size classes, affect the stability of three-phase froths in a synthetic pyrite-quartz ore. A novel bench-scale continuous column flotation cell was used to assess froth stability and metallurgical performance. Results obtained show that froth stability decreases as a function of increasing feed particle size. When particle size is transformed to surface area, a linear relationship between froth stability and particle-specific surface area is obtained. The effect on flotation performance is reflected by an increase in valuable mineral recovery as froth stability increases.