Simulations of biomass pyrolysis using glued-sphere CFD-DEM with 3-D intra-particle models

TY - JOUR

T1 - Simulations of biomass pyrolysis using glued-sphere CFD-DEM with 3-D intra-particle models

AU - Lu, Liqiang

AU - Gao, Xi

AU - Shahnam, Mehrdad

AU - Rogers, William A.

N1 - Publisher Copyright: © 2021 Elsevier B.V.

PY - 2021/9/1

Y1 - 2021/9/1

N2 - The shape of biomass particles influences intra-particle heat transfer, particle-particle collisions, interphase momentum, heat transfer, and pyrolysis yield. In this research, the effects of these multi-scale phenomena are captured using a glued-sphere computational fluid dynamic discrete element method (CFD-DEM) with 3-D intra-particle models. The glued-spheres resolved the shapes of particles and intra-particle temperature and species distributions. The implementation was validated using the pyrolysis data of a spherical particle and a cylindrical particle. Then, the influences of biomass shapes and sizes on pyrolysis were investigated. The results revealed the significant influence of surface areas and mass distributions on interphase heat transfer and chemical reactions. The intra-particle heat transfer is neglectable for a Biot number smaller than 0.41. Finally, the pyrolysis of irregularly shaped biomass particles in a fixed bed, fluidized bed, and spouted bed was simulated. Analysis of conversion distributions showed the largest deviations in the fixed bed and the slowest conversion rate in the spouted bed. A good balance between uniform and fast conversion is achieved in the fluidized bed. The multi-scale method proposed in this research provides a tool for the evaluation of large irregular-shaped biomass particle pyrolysis in different types of reactors.

AB - The shape of biomass particles influences intra-particle heat transfer, particle-particle collisions, interphase momentum, heat transfer, and pyrolysis yield. In this research, the effects of these multi-scale phenomena are captured using a glued-sphere computational fluid dynamic discrete element method (CFD-DEM) with 3-D intra-particle models. The glued-spheres resolved the shapes of particles and intra-particle temperature and species distributions. The implementation was validated using the pyrolysis data of a spherical particle and a cylindrical particle. Then, the influences of biomass shapes and sizes on pyrolysis were investigated. The results revealed the significant influence of surface areas and mass distributions on interphase heat transfer and chemical reactions. The intra-particle heat transfer is neglectable for a Biot number smaller than 0.41. Finally, the pyrolysis of irregularly shaped biomass particles in a fixed bed, fluidized bed, and spouted bed was simulated. Analysis of conversion distributions showed the largest deviations in the fixed bed and the slowest conversion rate in the spouted bed. A good balance between uniform and fast conversion is achieved in the fluidized bed. The multi-scale method proposed in this research provides a tool for the evaluation of large irregular-shaped biomass particle pyrolysis in different types of reactors.

KW - Biomass

KW - CFD-DEM

KW - Glued-sphere

KW - Intra-particle

KW - Pyrolysis

KW - Shape

UR - http://www.scopus.com/inward/record.url?scp=85103717678&partnerID=8YFLogxK

U2 - 10.1016/j.cej.2021.129564

DO - 10.1016/j.cej.2021.129564

M3 - 文章

AN - SCOPUS:85103717678

SN - 1385-8947

VL - 419

JO - Chemical Engineering Journal

JF - Chemical Engineering Journal

M1 - 129564

ER -