Separability curves (mineral recovery versus yield) have been used to characterize the copper flotation process both at batch laboratory scale and industrial plant scale (rougher banks). Then, to approach the scale-up problem the rougher bank operation and the batch were compared using the corresponding separability curves. Comparison was made at the maximum separation efficiency point in both operations. Thus, a time factor was established for optimal technical separation. The time factor can then be used for kinetic scale-up models, together wit h,the ratio between minerals recovery in both operating scales. Experience from several tests recorded over a period of 10 months in an industrial concentrator showed a good consistency for scaling-up the rougher flotation recovery from batch tests within a 1% absolute error range. The effect of particle size and air flowrate in laboratory batch tests was evaluated in the space of separability curves, regarding their effect on recovery at the optimum separability point. Also, the effect of pulp level and particle size on the bank flotation kinetics was evaluated in an industrial flotation circuit. Thus, estimation of recovery changes due to variations in mineral characteristics and operating conditions was explored. (C) 2003 Elsevier Science Ltd. All rights reserved.