Shear, selective and temperature responsive flocculation: A comparison of fine particle flotation techniques

Mineral flotation is a process whereby valuable hydrophobic mineral particles are recovered from low grade mineral pulp by means of attachment to air bubbles. Particles smaller than 10 μm have a low probability of collision with bubbles, due to their tendency to be caught in streamlines created by a rising bubble. This review focuses on the techniques aimed at increasing the effective size of ultrafine mineral particles through aggregation, as an aid in improving flotation performance. These techniques are: shear flocculation, selective polymer flocculation and temperature responsive flocculation. Each technique is evaluated in terms of its mechanisms and its efficacy at improving the flotation of fine mineral particles.