(409c) Low Cost and Low Energy Consumption Process to Convert Soluble Sugar and Homocelluloses in Sweet Sorghum Stalks Into Ethanol

Sweet sorghum is a promising feedstock for ethanol production due to its high fermentable sugar and homocellulose content in the stalks. The soluble sugar in sweet sorghum stalks can be converted into ethanol by a solid-state fermentation technology which uses the crushed stalks as culture substrates directly. Ethanol produced during the solid-state fermentation can be separated by distillation of these fermenting stalks. And the residue solid is called SSB which is rich with homocelluloses (70%). In present research, a process which combined ethanol separation stage after solid-state fermentation and alkaline pretreatment stage of SSB was designed for ethanol production with sweet sorghum. The process was optimized according to the yield of sugar-ethanol and amounts of monosaccharide released from SSB. In our novel process, energy consumption of mechanically squeeze and pretreatment of SSB was avoided. So it is efficient to reduce the cost of ethanol production with sugar crops and implement bio-conversion of all carbohydrates in sweet sorghum stalks. It is considered a promising process to produce ethanol at commercial scale.