Bridging particle and reactor scales in the simulation of biomass fast pyrolysis by coupling particle resolved simulation and coarse grained CFD-DEM. (28th April 2020)

• Record Type: Journal Article
• Authors: Lu, Liqiang; Gao, Xi; Shahnam, Mehrdad; Rogers, William A.
• Is Part Of: Chemical engineering science. Volume 216(2020)
• Publication Date: 2020-04-28
• Subjects: Biomass -- Pyrolysis -- CFD-DEM -- Coarse grained CFD-DEM -- Particle Resolved Simulation -- Fluidized Bed; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2020.115471
• Languages: English
• ISSNs: 0009-2509

Abstract

Graphical abstract: Highlights: The fluidized bed biomass pyrolizer was simulated using multi-scale CFD. The heat transfer correlation and reaction kinetics were calibrated using particle resolved simulations. A hybrid drag model was used to consider the different properties of sands and biomass particles. The predicted yields compare well with experiment data. Abstract: Efficient utilization of biomass is challenging due to the complexity of the feedstock at molecular, particle, and reactor scales. Direct coupling of particle scale model and reactor scale simulation is computationally infeasible. In this research, the results from a particle resolved simulation were used to calibrate the heat transfer and reaction kinetics of particles. A hybrid drag model was used to consider the different fluidization properties of sands and biomass particles. The computation cost was reduced using a coarse-grained Discrete Element Method (DEM). The simulated conversion rate, char yield, tar yield, and pyrolysis gas yield compare well with experiment. The residence time and axial distributions of biomass were also analyzed. This novel multi-scale method provides an efficient and accurate tool for the modeling of biomass pyrolysis reactors.