Predicting Power for a Scaled‐up Non‐Newtonian Biomass Slurry

Abstract

High-solids biomass slurries exhibit non-Newtonian behavior with a yield stress and require high power input for mixing. The goals were to determine the effect of scale and geometry on power number P 0 , and estimate the power for mixing a pretreated biomass slurry in a 3.8 million L hydrolysis reactor of conventional design. A lab-scale computational fluid dynamics model was validated against experimental data and then scaled up. A pitched-blade turbine and A310 hydrofoil were tested for various geometric arrangements. Flow was transitional; laminar and turbulence models resulted in equivalent P 0 which increased with scale. The ratio of impeller diameter to tank diameter affected P 0 for both impellers, but impeller clearance to tank diameter affected P 0 only for the A310. At least 2 MW is required to operate at this scale.

Volumetric Mass Transfer Coefficient in Fermenters: Scale‐up Study in Viscous Liquids

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Enzyme digestion of biofiber from mechanical heat treated municipal solid waste: Accessing kinetic and rheological design data using a pilot-scale high-solids mixer

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