Extension of liquid-limited trickle-bed reactor modelling to incorporate channelling effects

Evidence exists that, depending on the manner in which a bed is pre-wetted, some regions in a trickle-bed reactor may not be utilised due to the absence of liquid flow in these regions. However, liquid-limited trickle-bed reactors are usually modelled as if all of the particles are actively wetted. An average wetting efficiency is then used to represent the whole reactor. Previous work shows that, depending on the underlying hydrodynamic characteristics of the bed, an average wetting efficiency may not be representative for the whole population. By means of a simple reactor model, it is shown that for liquid-limited reactors the particle wetting distribution can accurately be represented by the average wetting efficiency and the fraction of completely dry particles alone. Data regarding the latter parameter is reported for different flow conditions and is shown to correlate well with related parameters in literature. (c) 2007 Elsevier Ltd. All rights reserved.