422 / 2018-07-31 11:48:35

Integrating sugarcane molasses into sequential cellulosic biofuels production based on SSF process of high solid loading

全体主题 > 其它

Sugarcane bagasse (SCB) is one of the most promising lignocellulosic biomasses due to its abundance and low price. However, bioethanol production from pure SCB fermentation is still limited by its high process cost and low fermentation efficiency. Sugarcane molasses, as a carbohydrate-rich biomass, can provide fermentable sugars for ethanol production. In this research, molasses were integrated into lignocellulosic ethanol production to boost the final ethanol concentration and ethanol yield in batch modes. The co-fermentation of pretreated SCB and molasses at ratios of 3:1 (mixture A) and 1:1 (mixture B) were conducted at solid loadings of 12% to 32%. While, the fermentation of pretreated SCB alone at the same solid loadings was also compared. At solid loading of 32%, ethanol concentrations of 64.10 g/L, 74.69 g/L, 75.64 g/L were obtained from pure SCB, mixture A, and mixture B, respectively. To further boost ethanol concentration, the fermentation of mixture B (1:1) with higher solid loading of 36% to 48% was also implemented. The highest ethanol concentration of 94.20 g/L was generated at high solid loading of 44% with the ethanol yield of 72.37%. In addition, after evaporation, the wastewater could be converted to biogas by anaerobic digestion. The final methane production of 312.14 mL/g volatile solids (VS) was obtained and the final chemical oxygen demand (COD) removal and VS degradation efficiency was 85.9% and 95.9%. Sequential biofuels production could improve the utilization of biomass resource.