Among several pretreatment technologies currently being pursed, alkaline pretreatments are the most promising ones, since they produce lesser sugar and lignin degradation products during pretreatment that are good for downstream processing. One of the three bioenergy centers funded by Department of Energy (DOE), Great Lakes Bioenergy Center (GLBRC) are committed to develop alkaline pretreatments like, Alkaline Hydrogen Peroxide pretreatment (AHP), Ammonia Fiber Expansion pretreatment (AFEXTM) and Extractive ammonia (EA) pretreatments (that facilitates partial removal of lignin). Nevertheless, in order to consider the implementation of these technologies in an industrial scale it is necessary to determine their economic viability when operating on a large scale bio refinery.
In this work, a techno economic analysis of the application of AHP, AFEXTM and EA pretreatments on a bio refinery that processes 2000 tons of corn stover per day for the production of ethanol has been done. Various cost elements like water usage, energy requirements, capital cost, amount of catalyst used and recovered, amount of enzyme used and water recycling are taken in to consideration for doing this analysis. We have identified the minimum Ethanol selling price required for each of these pretreatments as well as the existing bottlenecks that have to be addressed in order to develop a competitive pretreatment applicable at large scale facility.