Process simulation of ethanol production from biomass gasification and syngas fermentation

- New gasification-syngas fermentation process model was developed using Aspen Plus.
- Model consists of gasification, fermentation and product recovery modules.
- 36.5 million gallons ethanol are produced from 1200 tons switchgrass per day.
- Syngas fermentation yields 97.7 gallons ethanol per dry ton of biomass.
- Sensitivity analyses were performed on gasification and fermentation parameters.

The hybrid gasification-syngas fermentation platform can produce more bioethanol utilizing all biomass components compared to the biochemical conversion technology. Syngas fermentation operates at mild temperatures and pressures and avoids using expensive pretreatment processes and enzymes. This study presents a new process simulation model developed with Aspen Plus® of a biorefinery based on a hybrid conversion technology for the production of anhydrous ethanol using 1200 tons per day (wb) of switchgrass. The simulation model consists of three modules: gasification, fermentation, and product recovery. The results revealed a potential production of about 36.5 million gallons of anhydrous ethanol per year. Sensitivity analyses were also performed to investigate the effects of gasification and fermentation parameters that are keys for the development of an efficient process in terms of energy conservation and ethanol production.