Leaf and Panicle Separator for Sweet Sorghum

Abstract

High-biomass sweet sorghum is considered a promising energy crop suitable for the production of energy, first- and second-generation biofuels and biobased chemicals. Processing in a typical sugar cane mill or dedicated sorghum mill is challenged by the presence of trash (leaves and panicles). The separation of leaves and panicles could generate additional value streams, and the reduction of trash is considered beneficial for juice extraction and juice quality. A two-stage trash removal system for the separation of leaves, and panicles was designed and tested. The pneumatic leaf separation stage allowed the removal of up to 56% of leaves in a single pass and the second stage, a novel rotating-disk separator, demonstrated the feasibility of the panicle separation. The basic design parameters were optimized for both systems, and the impact of trash removal tested on Ceres® Inc. “Durasweet” sorghum in 2015 and 2016. Trash removal from the feedstock allowed practically identical recovery (97.3–99.9%) of soluble solids, while up to 19.1% less feedstock with significantly less fiber (82.6% of original feedstock) was processed.