RATIONAL DESCRIPTION OF TRICKLE FLOW THROUGH PACKED-BEDS .1. LIQUID DISTRIBUTION FAR FROM THE DISTRIBUTOR

The aim of the first part of this paper is to obtain a simple rational description of trickle flow, which may be extended to a radial dispersion study. Indeed, a straightforward extension of the results, derived previously on the basis of a thermodynamical analogy (P. Marchot, M. Crine and G. A. L'Homme, Chem. Eng. J., 36 (1987) 141), has not been possible until now. This is the reason why, in part I, we examine carefully the probabilistic content of our method. Then, on this basis, the results are generalized in part II. Simple probabilistic reasoning leads to analytical relations between liquid flow-rate distributions, and the irrigated fraction of the bed and the operating conditions. These relations (at the limit) can also be derived by maximizing the informational entropy of the system. This method provides numerical algorithms which are used to simulate the flow structure within beds of realistic length. The theoretical results are compared with numerical simulations, and with experimental distributions measured on biofilters using four different types of packing.