The formation of bubble clusters in flotation cells

Previously unpublished photographs of bubble clusters rising out of industrial flotation cells are presented, that provide further evidence of cluster formation. The mechanics of cluster formation are discussed, and the implications for the modelling of the flotation process, and the performance of flotation cells, are explored. Clusters would be expected to lead to increased entrainment of non-floating particles into the froth in industrial cells, resulting in reduced product purity or grade. Cluster formation would be expected to increase the flotation recovery of coarse particles.