Modelling of liquid dispersion in trickle-bed reactors: Capillary pressure gradients and mechanical dispersion

Modelling is one of the most significant prospective tools for design and analysis of trickle-bed reactors. Unfortunately current hydrodynamic models, developed on laboratory experiments, often work poorly in industrial scale. Therefore physically more authentic models are required, in which the small scale phenomena are separated from the large-scale phenomena. This would improve the scale-up of the model, and consequently its applicability to industrial-scale reactors. One of the reasons, why current models fail in industrial-scale reactors, is that radial distribution of liquid is not considered in the model development. Here models for liquid distribution, caused by capillary pressure gradients and mechanical dispersion, are suggested and the outline of the implementation of these models to CFD programs is presented. Laboratory experiments and CFD simulations of the experimental setup are performed to gain better understanding about liquid radial distribution. The physical validity of the presented models is assessed on the consistency between the experimental and the modelled liquid flow profiles.