Low Energy Particle Size Reduction for Biomass Feedstocks

Size reduction, or comminution, is a necessary, but energy intensive, processing step in the conversion of lingo-cellulosic biomass feedstocks into biofuels, including ethanol, bio-oil, and other products. Comminution ¿ by chippers, grinders, hammer mills, and the like ¿ not only consumes excessive energy but also produces a wide particle size distribution and often requires costly dust control and mitigation. This project will develop a comminution system that employs a rotary bypass shear and material crusher that work with the biological structure of the cellulosic feedstocks to improve energy efficiency. Moreover, the system has the capability to narrow the range of particle sizes to improve conversion efficiency. The size reduction process would be useful for conversion processes that can handle feedstocks in the 4-12 mm particle size or as the primary size-reduction process in two stage systems. Commercial Applications and other Benefits as described by the awardee:The new comminution system would enable the design, manufacture and implementation of new pre-processing equipment for bioenergy facilities, reducing the energy cost for primary particle size reduction by at least 50 percent compared to grinders and hammer mills