(573b) Flowability of Biomass Solids: The Effects of Preprocessing

Crawford, N. C., National Renewable Energy Laboratory
Nagle, N. J., National Renewable Energy Laboratory
Sievers, D. A., National Renewable Energy Laboratory
Stickel, J. J., National Renewable Energy Laboratory
Ray, A. E., Idaho National Laboratory

Continuous and reliable feeding of biomass is essential for successful biofuel production. However, the challenges associated with biomass solids handling are commonly overlooked. Proper biomass feeding is difficult because biomass particles are inherently heterogeneous, varying greatly in size, shape, density, moisture content, and compressibility (to name a few). In addition, minor alterations to the biomass, such as changes in moisture content or particle size, can significantly impact solids-handling systems. A feed system will commonly work well for one material and completely fail for another material with similar properties. In this study, we examine the effects of preprocessing (particle size reduction, moisture content, chemical additives, etc.) on the flow properties of corn stover. Compressibility, interparticle friction, cohesion, yield stress, and wall friction were assessed using Freeman Technology’s FT4 powder rheometer (a novel application of the FT4). The objective of this work was to elucidate the impact of preprocessing on the flowability and compressibility of corn stover and to link laboratory-scale flow measurements with feed performance in pilot-scale processing equipment.