3D chemical reactor LB simulations

Abstract

The lattice Boltzmann (LB) method was used to simulate hydrodynamics and mass transfer, with reaction, in a 3D packed bed of porous catalyst particles. The current LB implementation enables particle Peclet numbers up to 1 0 8 to be readily simulated. Importantly we are able to easily and efficiently simulate realistic values of diffusivity and realistic values for the ratio of liquid viscosity to diffusivity. In addition, the mass transfer simulations are modified to permit spatially varying values of diffusivity, essential to differentiate between intra- and inter-particle diffusivity ( D intra and D inter , respectively). We investigate the effect of D intra and D inter on reaction conversion for a commercially relevant esterification reaction. The 3D simulations are conducted on an experimentally determined MRI image of a random packed bed of porous catalyst particles. Particle Reynolds and Peclet numbers were 0.13 and 88.4, respectively. The value of D intra is found to have a limited effect for D intra > 0 , which is in good agreement with an analytical study of catalyst effectiveness in literature for this reaction system. Simulated 3D conversion data agrees quantitatively well with the experimental findings.