Proposing a seven-parameter kinetics model for predicting cerussite flotation recovery

Sulfide lead resources are being depleted and the exploitation of carbonate lead deposits is now the main focus of lead mining. Cerussite, PbCO3, is majorly discarded to tailing damps because it is difficult to be processed by flotation in lead concentration units. This paper not only investigates the optimization of cerussite flotation, but it also proposes a model for predicting the recovery. Froth flotation was used for cerussite recovery from a previously existing tailing damp in the ChahGaz mine in Kerman Province, Iran. The response surface method was used for experimental design and optimization of Pb flotation in which a statistical experimental model was suggested to model flotation kinetics based on the effective parameters. The results showed that particle size, pH, solid content, Na2S dosage, collector dosage and collector type to be the most effective parameters. These parameters were applied for investigating flotation kinetics. A three-fraction (with seven-parameter) flotation model, with fast, medium and slow kinetics rate constants was obtained via 64 designed tests. The proposed model showed a good agreement with experimental data (R2 more than 0.8). Also optimum conditions of cerussite flotation were set at pH= 9, d80= 53 µm, solid content= 26%, Na2S= 4000 g/t and collector dosage = 1500g/t of PAX.