In this paper

based on an analysis of the Ergun equation used for single phase flow in a packed bed

characteristic scales of flow are established for an equivalent representation of gas-liquid two phase flows in low and high pressures trickle beds. In terms of the scales and using available data by different authors

new improved correlations for evaluation of two phase pressure drop and phase holdups are proposed for porous and non-porous packings with equivalent diameters of 1.5—6 mm

and for modified Reynolds number from 3.3 to 88

operation pressures up to 6 MPa and superficial gas velocities up to 8.8 cm·s-1. The evaluation gives a mean relative deviation 35.8% for the two phase pressure drop

and a mean relative deviation 11.2% for liquid holdup.