Bank profiling and separation efficiency

• We modelled a rougher bank modelled in JKSimFloat using a three mineral system.
• We created six bank profiles to compare gangue recovery by true flotation and entrainment.
• Simulations support the effect of bank profile on separation efficiency.
• A balanced recovery profile provides the best separation efficiency against floatable gangue.
• A balanced mass profile provides the best separation efficiency against entrained gangue.

Various authors have discussed methods of optimising a bank of flotation cells. In this paper, JKSimFloat is used to investigate the effect of recovery profiling and mass pull profiling (i.e., mass distribution to cells in a bank) on the separation efficiency between floatable minerals and against entrained gangue.In the case of two floatable minerals, a balanced recovery profile was found to be optimal: supporting and extending previous analysis. In the case of separation of a floatable mineral from entrained gangue, the entrainment model that links water overflow rate to solids overflow rate was employed. When the value of b in the entrainment model is greater than one, a balanced mass pull profile was found to be optimum. The evidence for b > 1 is briefly reviewed; no example has been found where b < 1. Most of the profiles were controlled in the software by altering the bubble surface area flux distribution; a sensitivity analysis was performed using other variables.Recovery profiling was tested as part of a bank optimisation campaign at a talc operation in Timmins, Canada. Using air and frother as manipulated variables, it was found that as the rougher bank was moved toward a balanced profile the final plant product showed improvement in grade and yield.