Integrating sugarcane molasses into sequential cellulosic biofuel production based on SSF process of high solid...

Area of Science:

• Biotechnology
• Renewable Energy
• Biochemical Engineering

Background:

• Sugarcane bagasse (SCB) is a promising lignocellulosic biomass for biofuel production.
• High processing costs and low fermentation efficiency limit bioethanol production from pure SCB.
• Sugarcane molasses offers fermentable sugars to improve ethanol production economics.

Purpose of the Study:

• To reduce high processing costs in lignocellulosic ethanol production.
• To improve fermentation efficiency and boost final ethanol concentration and yield.
• To investigate the co-fermentation of SCB and molasses.

Main Methods:

• Co-fermentation of pretreated SCB and molasses at various ratios (3:1 and 1:1).
• Experiments conducted at solid loadings ranging from 12% to 48%.
• Comparison with fermentation of pretreated SCB alone.
• Anaerobic digestion of wastewater for biogas production.

Main Results:

• Co-fermentation of SCB and molasses (1:1 ratio) at 44% solid loading yielded the highest ethanol concentration (94.20 g/L) and ethanol yield (72.37%).
• Ethanol concentrations of 75.64 g/L were achieved with a 1:1 SCB-molasses mixture at 32% solid loading.
• Wastewater from the process was converted to biogas, achieving 312.14 mL/g VS methane production with high COD and VS removal efficiencies (85.9% and 95.9%).

Conclusions:

• Molasses creates a favorable environment for yeast and inoculum growth.
• Integrating molasses into cellulosic biofuel production enhances biomass resource utilization.
• Co-fermentation is a viable strategy to improve the economics and efficiency of bioethanol production from SCB.