Identification of feed and simulation of industrial flotation circuits

Abstract

Feed to flotation circuits is characterized by conjugate distributions of total mass and mineral mass in apparent flotation rate constant as the common attribute. The rate constant is interpreted as a lumped kinetic parameter in a fairly detailed multi-phase flotation model which explicitly incorporates bubble phase and froth stability index. A method is described for identification of the discretized conjugate distributions from flotation plant data. The procedure entails random search of optimum feed parameters in conjunction with repeated simulation of the circuit in two parallel mathematical streams, one for total mass flows and second for mineral flows only. Feeds to three industrial flotation plants have been identified for which flotation data are available in literature. The plants could be simulated stage-wise quite accurately with two to five species description of the feed. From these results and extensive trials based on computer-generated flotation data, it is concluded that the inverse problem of feed identification can be solved. The identified feed is meaningful for circuit simulation, provided the flotation rate is scaled in each stage of the circuit to account for variations in pulp density and chemistry, residence time, aeration rate and froth stability. Some applications are discussed.