Experimental measurements of hydrodynamic and interfacial area parameters are carried out over two rectangular pilot scale valve tray columns. The effect of tray path length on extrapolation between the two columns is studied and phenomenological correlations for hydrodynamic and interfacial area are proposed. Correlations are compared both to literature and to industrial results showing good agreement and a significant improvement for the prediction of industrial conditions. Discrepancies preventing an accurate description of industrial trends are highlighted through comparison between typical emulsion height profiles on both columns. (C) 2014 Elsevier Ltd. All rights reserved.