Planning industrial flotation operation and earlier flotation equipment sizing are commonly based on batch flotation testing, where ideal operating conditions can be provided. Each plant has its own batch flotation standards and typically uses a time scale-up factor in order to compare laboratory and plant flotation performance. However, flotation scale-up is more complex, and it is not yet completely understood. In this work, a novel scale-up approach was developed, where the effects of the hydrodynamic regime (mixing), solid segregation (effective residence time) and froth recovery on the plant flotation rate were identified and evaluated. Each effect was then described by means of correction factors applied on the batch flotation rate, which was considered the optimal condition. These factors can be determined from laboratory and plant experimental data. This methodology was successfully applied at the rougher copper flotation plant of Codelco Norte Division, Codelco-Chile, for cells of 160 and 300 m(3). (C) 2010 Elsevier Ltd. All rights reserved.