Statistical Study of the Influence of Operating Parameters on Entrainment Rate of Slimes in Froth Flotation Using Ross Method

In this paper, effect of operating parameters on entrainment rate of fine particles in froth flotation was studied. Main and interaction effects of frother concentration, solid content and particle size on entrainment factor were assessed using a full factorial experimental design and results were interpreted by analysis of variance method. Ross method was used to determine entrainment factor for each experiment. Results showed that the entrainment factor would increase by decreasing solid content and particle size. The chance of particle to transfer to froth zone increases by increasing solid content since it improve the dispersion of particle throughout the pulp which further increases the froth solid content and retention time and therefore, the chance of dropping particles back to the pulp increases which leads to the decrease of concentration of particles enters to froth zone by entrainment mechanism. In addition, particles with smaller diameter will show higher entrainment rate relative to those with larger diameter due to water wake effect behind rising bubbles. Therefore, entrainment factor would decrease as particle size increases. Frother concentration effect was also found to be insignificant. In addition, the only significant interaction was that between solid content and particle size.

Keywords:

Froth flotation , Entrainment rate , Selectivity , Ross Method