We report results
from a multiscale computational modeling study
of biomass fast pyrolysis in an experimental laboratory reactor that
combined the hydrodynamics predicted by a two-fluid model (TFM) with
predictions from a finite element method (FEM) simulation of heat
and mass transfer and chemical reactions within biomass particles.
The experimental pyrolyzer consisted of a 2 in. (5.1 cm) diameter
bubbling fluidized bed reactor (FBR) fed with milled pine pellets.
The predicted FBR hydrodynamics included estimates of the residence
times that the gas and biomass particles spend in the reactor before
they exit. A single-particle FEM simulation was constructed on the
basis of the geometry and heat transfer properties determined from
optical and X-ray computed tomography measurements of wood and char
particles collected from the experimental FBR, along with previously
proposed pyrolysis reaction kinetics. Taken together, the combined
TFM and FEM simulation results predicted net bio-oil yields at the
reactor exit that agree well with experimental observations, without
any arbitrary fitting parameters. The combined computational models
also provided practical information about the most important reactor
and feedstock parameters.
The impact of bubbling bed hydrodynamics on temporal variations in the exit tar yield for biomass fast pyrolysis was investigated using computational simulations of an experimental laboratory-scale reactor. A multi-fluid computational fluid dynamics model was employed to
We report results from a computational study of the transition from bubbling to slugging in a laboratory-scale fluidized-bed reactor with Geldart Group B glass particles. For simulating the three-dimensional fluidized-bed hydrodynamics, we employ MFiX, a widely studied multi-phase flow simulation tool, that uses a two-fluid Eulerian-Eulerian approximation of the particle and gas dynamics over a range of gas flows. We also utilize a previously published algorithm to generate bubble statistics that can be correlated with pressure fluctuations to reveal previously unreported details about the stages through which the hydrodynamics progress during the bubbling-toslugging transition. We expect this new information will lead to improved approaches for on-line
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.