Flotation and entrainment of particles during batch flotation tests

A novel technique is proposed that allows the contributions made by true flotation and the entrainment of mineral particles during the flotation process to be determined. A transfer factor for entrained particles, which describes the differential classification of entrained particles and water, is calculated from the recoveries of solids and water, and changes in the composition of the pulp with time during a batch flotation test. Laboratory-scale test work was conducted, during which various amounts of floatable gangue materiass from three different sources were substituted for the feed (a pyritic dump residue). The results show that, as the degree of substitution increased, the ratio of floated to entrained particles decreased, while the transfer factor and the stability and mobility of the froth increased. These trends were independent of the origin of the gangue material, and indicate that an excessively stable froth increases the amount of material that is recovered by entrainment.