Chemical Engineering & Technology, Vol.36, No.1, 43-52, 2013
Numerical and Experimental Study of Catalyst Loading and Body Effects on a Gas-Liquid Trickle-Flow Bed
The influence of tortuosity and fluid volume fractions on trickle-flow bed performance was analyzed. Hydrodynamics of the gas-liquid downward flow through trickle beds, filled with industrial trilobe catalysts, were investigated experimentally and numerically. The pressure drop and liquid holdup were measured at different gas and liquid velocities and in two different loading methods, namely, sock and dense catalyst loading. The effect of sharp corners on hydrodynamic parameters was considered in a bed with rectangular cross section. The reactor was simulated, considering a three-phase model, appropriate porosity function, and interfacial forces based on the Eulerian-Eulerian approach. Computational fluid dynamics (CFD) simulation results for pressure drop and liquid holdup agreed well with experimental data. Finally, the velocity distribution in two types of loading and the effect of bed geometry in CFD results demonstrated that pressure drop and liquid holdup were reduced compared to a cylindrical one due to high voidage at sharp corners.
Keywords:Computational fluid dynamics;Dynamic liquid holdup;Multiphase flows;Trickle-bed reactor;Trilobe catalysts