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Random Walk Model for Biomass Particle Mixing in Bubbling Fluidized Beds

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Abstract

We propose a physically motivated random walk model to describe the spatial and temporal mixing of a single biomass particle in a bubbling fluidized bed. The model parameters are estimated from measurements of a magnetically tagged simulated biomass particle in a laboratory fluidized bed. We demonstrate that Monte Carlo simulations using the model match key statistical features of the observed behavior reasonably well. These results suggest that a model of this type can simulate the effects of biomass particle mixing in biomass conversion reactors. We suggest possible improvements to the random walk model and propose how it might be used in conjunction with computational fluid dynamics simulations.

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... • The Weibull distribution [see Halow etal (2012) and Daw and Halow (2014)]. ...
... A key aspect of these previous applications is that the rate of predicted events of interest is proportional to a power of time. More recently, magnetic tracking of simulated biomass particle motion in bubbling fluidized beds has been shown to be consistent with a type of correlated random walk that can be represented with Weibull statistics [Daw and Halow (2014)]. For these experiments, the Weibull model also appeared to account for particle size and density segregation effects, which are not considered in the above models. ...
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