An Integrated Membrane-based Process Train for Reducing Costs of Ethanol Production

Domestic ethanol production has grown substantially over the last 30 years due to a growth in national energy security concerns, more stringent Federal standards for vehicle emissions, and government agricultural incentives. The recently signed Federal energy legislation requires an increase in ethanol production to 7.5 billion gallons a year within the next 10 years. There is, however, a recognized need to reduce the production costs for fuel ethanol and to make its manufacture more energy-efficient. In the U.S., most ethanol derives from corn starch saccharification and fermentation. The production schemes used to produce ethanol from corn utilize mature unit operations (e.g., batch fermentation, distillation, centrifugation, evaporation), such that there are minimal marginal economic benefits for improving the productivities of these process operations. However, via incorporation of improved process operations, it will be possible to substantially decrease the production costs for starch-derived ethanol. The use of selective membranes as substitutes for conventional separation operations in corn refining have demonstrated significant process improvements and projected economic benefits. However, such technologies will require substantial pilot-scale demonstration to ensure that the risk of technical failure is minimized. The subject of this proposal is the development of an integrated membrane-based process that will provide substantial ethanol cost reduction and that builds upon existing membrane products that are unique to the proposing organization.