By Iva Jovanovic and Sandra Tjokro Rahardjo

Pacific Northwest National Lab, Richland WA

Filamentous fungi are well known cellulolytic producers and are currently utilized in research attempts to develop a consolidated ethanol production from biomass fermentation. A consolidated approach is achieved by combining enzyme production, saccharification, and fermentation in one reactor utilizing one strain of fungi. In this presentation a techno-economic analysis of a filamentous fungal fermentation ethanol plant utilizing corn stover as the carbon source is examined.

Two cases were modeled and considered for this bioprocess; a state of technology based model and a futuristic model dependent on further fungal research. The state of technology model examines cost and benefit of biomass-to-ethanol production today. Current bench scale fermentation processes data is used and a scale up analysis completed to evaluate costs. The limiting case model is designed as a futuristic case based on the same fermentation process with assumptions that fungal performance under the same fermentation conditions has been improved and milder pretreatment condition can be utilized due to better enzyme degradation. A more robust fungus is assumed which produces a greater quantity of biomass degrading enzymes, has enhanced function under micro-aerobic conditions, and has a higher tolerance of ethanol.

The intent of this work is to present the current state of fungal fermentation technology with respect to biomass-to-ethanol production and indicate areas of research which need further development and attention to achieve a competitive ethanol market price.