Quantifying the frother potential of industrial flotation cell process water using dilution curves

Effective frother dosing in flotation circuits is challenging due to varying process water chemistry, frother volatility, and partitioning effects that create unknown background frother potential. This study presents a dilution-curve methodology to quantify frother potential Ψ − a dimensionless indicator of coalescence suppression capacity relative to the critical coalescence concentration (CCC 95 ). The method systematically dilutes process water while measuring bubble size ( d 32 ) under controlled aeration, then aligns the resulting curve to infer Ψ and, with the use of a frother specific reference curve, equivalent concentration C eq . Laboratory validation with MIBC (6–50 ppm) showed agreement between inferred and known concentrations (RMSE = 0.97 ppm, MAPE = 4.5 %). Tests with MIBC in 0.2 M and 0.7 M NaCl demonstrated the method’s ability to quantify Ψ in the presence of background water chemistry, with electrolyte alone achieving Ψ = 1.02 for 0.2 M NaCl and Ψ = 1.62 for 0.7 M NaCl. A plant case study on a copper rougher bank revealed pre-flotation process water frother potential ( Ψ = 0.65) and cellwise profiles ( Ψ = 2.81, 2.14, 2.15, 2.14, 2.24) indicating operation well above CCC 95 with partitioning effects. The method provides actionable frother control metrics, enabling cell-specific dosing adjustments and gas dispersion optimization.