Liquid biofuels produced through the biochemical processing of lignocellulosic biomass are considered as sustainable energy alternatives to the depleting fossil fuels. The products of the Acetone-Butanol-Ethanol (ABE) fermentation process are used as liquid transportation fuels (butanol and ethanol), solvents and for the production of other chemicals. A major hurdle, however, in transitioning to biofuels produced from lignocellulosic feedstock in a traditional biorefinery is the need to harvest, transport and process large volumes of these feedstocks to provide a continuous fuel supply. Farms have the space to store biomass and time to accomplish biomass processing. A proposed on-farm high-solids biomass processing, therefore, circumvents the transportation and storage of sheer volumes of the feedstock needed at a central processing facility. Furthermore, on-farm bioprocessing uses the existing agricultural framework to convert lignocellulose to ABE fermentation solvents as semi-finished products that can be shipped economically to traditional biorefineries for further processing into products that meet market standards.
The profitability of the on-farm processing system depends on the production capacity, processing technology employed, product profile, product concentration leaving the on-farm bioprocess, governmental policies, market and environmental factors. These factors are interrelated such that decisions made with regard to one factor affect all the others and the overall profitability. Process System Engineering (PSE) is an approach that is well suited to solve such a complex interplay of policies, process simulation and optimization of the on-farm bioprocess. To this end, this research aims to develop a multidisciplinary framework that integrates process simulation and optimization of the ABE production by fermentation and products separation. The commercial simulation packages, Aspen Engineering SuiteTM, IBM ILOG® Optimization Program Language (OPL), Microsoft Excel® and MATLAB will be employed in this research to simulate, optimize and perform economic analyses of the on-farm high solids ABE production by fermentation and the subsequent product concentration into semi-finished products based on dynamic mathematical models. The multidisciplinary framework should allow the various discrete models to be linked and exchange information and data. The multidisciplinary framework can be used to determine the quantities and concentrations of products leaving the farm that are economically profitable to be shipped to a central traditional biorefinery and assess how the profitability of an on-farm high-solid biomass processing to produce ABE as semi-finished products compares with the profitability of a centralized processing facility that processes lignocellulosic biomass into biofuels in a traditional biorefinery. Thus, the multidisciplinary framework will provide a decision support tool that can be used to assess the economic viability of a proposed on-farm ABE production process using various feedstocks to produce semi-finished products.
See more of this Group/Topical: Sustainable Engineering Forum