Coupling CFD–DEM and microkinetic modeling of surface chemistry for the simulation of catalytic fluidized systems

Abstract

In this work, we propose numerical methodologies to combine detailed microkinetic modeling and Eulerian-Lagrangian methods for the multiscale simulation of fluidized bed reactors. In particular, we couple the hydrodynamics description by computational fluid dynamics and the discrete element method (CFD-DEM) with the detailed surface chemistry by means of microkinetic modeling. The governing equations for the gas phase are solved through a segregated approach. The mass and energy balances for each catalytic particle, instead, are integrated adopting both the coupled and the operator-splitting approaches. To reduce the computational burden associated with the microkinetic description of the surface chemistry, in situ adaptive tabulation (ISAT) is employed together with operator-splitting. The catalytic partial oxidation of methane and steam reforming on Rh are presented as a showcase to assess the capability of the methods. An accurate description of the gas and site species is achieved along with up to 4 times speed-up of the simulation, thanks to the combined effect of operator-splitting and ISAT. The proposed approach represents an important step for the first-principles based multiscale analysis of fluidized reactive systems.

Computational Fluid Dynamics of Reacting Flows at Surfaces: Methodologies and Applications

“…Schematic representation of the operator splitting (right branch) and the operator coupling (left branch) numerical strategies. Adapted with permission from 63.…”

Oxidative Coupling of Methane for Ethylene Production: Reviewing Kinetic Modelling Approaches, Thermodynamics and Catalysts

“…Their simulations were carried out using the Euler-Euler (EE) model approach based on the kinetic theory of granular flow. In the EE approach, both gas and solid phases are interpenetrating fluids [132]. For each gas and solid phase, the model comprises momentum conservation equations, which are linked by interphase momentum transfer, energy conservation equations, including a radiative heat transfer between the reactor wall and the feed, and mass conservation equations for each compound.…”

Product Design and Engineering in Chemical Engineering: Past, Present State, and Future

“…. It seems that the LB and VOF approaches are the best candidates to link CFD with CCH, e.g., for modeling colloidal dynamics with mesoscopic features , for the simulation of the expansion of polyurethane foams of industrial interest , or for the modeling of surface chemistry for the simulation of catalytic fluidized‐bed reactors . In addition, another interesting potential option is the integration of the mesoscale modeling (MM) techniques, i.e., micro finite elements (microFE) with CFD approach, which could provide information on properties of pure components or complex materials .…”