Use of CFD for pressure drop, liquid saturation and wetting predictions in trickle bed reactors for different catalyst particle shapes

[Display omitted] •Multiphase flow simulation in Trickle-Bed Reactors (TBR) using the Volume-Of-Fluid approach (VOF)•Pressure drop, liquid saturation and wetting efficiency prediction are investigated.•Three different catalyst shape particle loadings: spheres, trilobes and quadrilobes are studied.•Satisfactory predictions of hydrodynamic parameters: two-phase pressure drop, liquid saturation and wetting efficiency.•New wetting efficiency correlation accounting for gas velocity and particle shape effects. The characterization of hydrodynamics in Trickle-Bed-Reactors is a complex task due to the opacity of the medium. In particular, the determination of pressure drop, liquid saturation , wetting of the catalyst surface and catalyst shape effect on these parameters is very important for optimal catalyst use and reactor operation. Measurements under industrial conditions are limited to indirect estimations, and direct measurement methods are limited to near-ambient conditions. In this context, the objective of the present article is to use Computational-Fluid-Dynamics to investigate pressure drop, liquid saturation and wetting efficiency in Trickle-Bed-Reactors and to improve existing correlations, with a special focus on the catalyst shape effect and wetting prediction. The Volume-Of-Fluid approach was used to simulate two-phase flow through particle loadings of spherical, trilobe and quadrilobe-shaped particles. The numerical model was validated against literature correlations in terms of pressure drop, liquid holdup and wetting efficiency. The CFD model was then employed to explore two effects that does not reach out a consensus in existing literature, i.e effects of particle shape and gas-phase velocity on wetting efficiency. As a result, it was shown that CFD provides good predictions of pressure drop and liquid saturation for different catalyst particle shapes, the achieved deviations between CFD results and correlation estimations are below 20%. A new wetting efficiency correlation is also proposed. This new correlation is able to predict wetting efficiency with a precision of 6.99% for a wide range of liquid velocities (from 0.2 to 0.8 cm/s) and gas velocities (from 5 to 20 cm/s) and three particle shapes.