(44b) Flow Characterization of Biomass Solids

Crawford, N. C., National Renewable Energy Laboratory
Sievers, D. A., National Renewable Energy Laboratory
Stickel, J. J., National Renewable Energy Laboratory

The conversion of biomass, specifically lignocellulosic biomass, into fuels has the potential to provide renewable alternatives to those derived from fossil carbon sources (oil, natural gas, and coal). Currently, biomass transport is a key obstacle for the cost-competitive production of biofuels. Their elasticity and irregular shape make biomass solids exceedingly difficult to process. Therefore, a better understanding of biomass flowability is needed in order for engineers to develop cost-effective processing strategies.

In the work presented here, we examine the flow characteristics of biomass solids using Freeman Technology’s FT4 powder rheometer (a novel application of the FT4). Compressibility, shear cell, wall friction, and the tendency for bridge formation were assessed for milled corn stover (unmodified, acid-sprayed, and deacetylated), as well as more “model-like” biomass materials (α-cellulose). In order to validate the use of the FT4 for characterizing biomass particulates, FT4 results were compared to literature data gathered using more established shear testing technologies. Overall, the FT4 can provide robust and reliable flowability data for biomass solids.