Biomass to Ethanol: Process Simulation, Validation and Sensitivity Analysis of a Gasifier and a Bioreactor

Abstract

The Gasification-Fermentation process for the production of fuel-grade ethanol from agricultural biomass is being investigated at Oklahoma State University, Stillwater. Process simulation software, Aspen Plus was used to study the gasifier and the bioreactor set-ups in this research. Process models were developed and validated with experimental data. Sensitivity studies were conducted for the gasifier by manipulating important process parameters like biomass feed rate, moisture content, operating temperature and equivalence ratio. Sensitivity of the bioreactor model was studied by manipulating the input gas composition of carbon monoxide, carbon dioxide and hydrogen gases, media flow rate, and stoichiometric conversion of substrates. The results from this work indicate that, the amount of carbon monoxide and hydrogen gases produced in the gasifier and the amount of ethanol produced in the bioreactor can theoretically be improved further.