Process Simulation for Intensified Ethanol Production from Syngas Fermentation

Abstract

Microbial syngas conversion to liquid fuels, and commodity chemicals has emerged as a potential technique to extract energy from biomass, coal, and exhaust gases. Environmentally friendly consumption of fossils for short-term and renewable for long-term could be realized by scale-up of syngas fermentation. However, lower enzyme productivity and subsequent higher separation cost is causing hindrance in successful commercialization of this technology. Due to the lesser ethanol concentration in fermentation broth, conventional distillation scheme is consuming a major portion of total energy requirement of the process. The present study is designed to intensify the bioethanol production process by integrating pervaporation just after the fermentation. In order to make a fair conclusion pervaporation integration is applied on three different existing distillation based schemes. Comparison on the basis of energy consumption and economics is presented. The proposed pervaporation based scheme to obtain ethanol is then compared with conventional distillation based configuration recently published. The membrane based configuration showed 41.08% savings as compared to conventional technique resulting in intensified production process.