On the froth transport modelling in industrial flotation cells

Abstract

A froth transport model for industrial flotation cells characterisation has been developed in terms of operating variables for a three-phase system (i.e., gas, liquid and valuable/non-valuable solid). The new approach, based on previous literature, involves three transport mechanisms: a vertical transport zone, a combined vertical and horizontal transport zone that allows the liquid and solid phases to be carried to the concentrate stream, and a mechanism in which the gas phase is gradually removed from the top of the froth (bubble collapse).To develop and evaluate the model, non-conventional measurements were conducted in a 130m3 flotation cell in the Cu/Mo rougher circuit at Division El Teniente, Codelo-Chile. The solid axial profile in the froth, the froth recovery and the froth transport times for the three phases (measured by radioactive tracers), are among the most important measured variables. The mean froth residence times and froth recovery estimations were used as boundary conditions in the proposed model.The aim of the froth transport model was to provide a simple and practical understanding of the froth performance in the flotation equipment. A practical description of the froth zone behaviour will allow new designs and configurations to be evaluated for the radial and peripheral launders in mechanical cells, improve the recovery of valuable minerals and decrease the gangue entrainment into the concentrate stream.