Integratıon of sweet sorghum ınto bıoethanol facılıtıes ın Turkey: Productıvıty and process analysıs
摘要
Several studies have evaluated the adaptation and yield of sweet sorghum in different regions of Turkey; however, its process compatibility and efficiency as an alternative feedstock for existing bioethanol plants have not yet been thoroughly assessed. In this study, three registered varieties of sweet sorghum in Turkey—Erdurmuş, Gülşeker, and Uzun—were cultivated at the research fields of Sarayönü Vocational School, Selçuk University, and harvested at maturity. Plant stalks were shredded and pressed to extract sap, yielding 2279 L (Erdurmuş), 3286 L (Gülşeker), and 747 L (Uzun) per decare. For processing, each variety of 5 L of sap was collected and stored at –20°C until use. Fermentation experiments were conducted at the Konya Sugar Bioethanol Plant using Saccharomyces cerevisiae in 3.5-L fermenters, followed by distillation under laboratory conditions. Practical trials produced 2.5 L of bioethanol from each variety, with concentrations of 32%, 35%, and 46%, respectively. Fuel analysis of the Uzun variety indicated a lower heating value (LHV) of 2180 cal/g despite containing 2.48% water by mass. Gas chromatography analysis revealed only trace impurities, and further dehydration was found necessary to achieve the 99.8% purity required for fuel-grade bioethanol. These findings provide preliminary evidence that sweet sorghum, particularly the Uzun variety, could be a promising candidate for integration into existing molasses-based bioethanol facilities in Turkey. With its potential to enhance production capacity while supporting sustainability, sweet sorghum represents a valuable alternative feedstock worthy of further research and development.