Modelling of the liquid distribution in a trickle flow packed column based upon X-ray tomography images

X-ray tomography is used to characterise the liquid distribution in a 0.6 meter diameter and 2 meter height column filled with gas-liquid absorption polypropylene packing elements (Cascade Mini-Ring 1A, Glitsch Benelux). The liquid holdup distribution is determined for liquid flowrates ranging from 1000 l/h to 6000 l/h, that correspond to superficial velocities ranging from 10(-3) to 6 10(-3) m/s, in several cross sections situated at different heights in the packed column. A characteristic length, corresponding to the smallest scale beyond which the packing properties may be supposed statistically homogenous and isotropic, as determined by Means of the autocorrelation function method applied to the images of the solid distribution. Both local and global liquid holdup measurements are satisfactorily modelled by means of a partial wetting model based on a probabilistic approach.