Woody biomass size reduction with selective material orientation

Background: Roundwood logs from forests and energy plantations must be chipped, ground, or otherwise comminuted into small particles prior to conversion to solid or liquid biofuels. Results & discussion: Rotary veneer followed by cross-grain shearing is demonstrated to be a novel and low energy consuming method for primary breakdown of logs into a raw material having high transport and storage density. Processing of high-moisture raw logs into 2.5-4.2-mm particles prior to drying or conversion consumes less than 20% of the energy required for achieving similar particle size with hammer mills, while producing a more uniform particle shape and size. Conclusion: Energy savings from the proposed method may reduce the comminution cost of woody feedstocks by more than half.