Small Scale Ethanol Drying

There continues to be a need for the production of fuel-grade ethanol from agricultural sources. The Federal Government is actively looking for biomass renewable feed stocks for enhancing gasoline and reducing our dependence on foreign oil. Ethanol from agricultural sources has many advantages, including fuel independence and its significant value as an oxygenate and octane improver. Unlike gasoline, ethanol does not generate net greenhouse gases. Also, with significant environmental pressure to move away from MTBE (methyl tertiary butyl ether) as an oxygenate because of its environmental impact, there is further need for ethanol. Despite a significant need for ethanol, the cost of agriculture-based ethanol, and most specifically, the energy costs associated with developing dry fuel-grade ethanol, are quite severe. Existing and new legislation provides significant incentives for use of fuel-grade ethanol. Costs for manufacturing fuel-grade ethanol, especially on small facilities, are significant. Membrane processes are ideal for small applications because the associated pumps scale down linearly. Therefore, while many existing biomass-to-ethanol plants are at 40 million gallons per year or greater and very few are at 10 million gallons per year, a membrane process focused on fuel-grade ethanol membranes would be the most advantageous. The product concept associated with this program is to operate primarily membrane and related processes to convert low volumes of biomass to fuel-grade ethanol. In Phase I, we will demonstrate all key components of the membrane process on water-ethanol streams. Using these basic data, we will facilitate an engineering evaluation to determine overall process costs. Our objective is to demonstrate a membrane process that is superior to any other process for 10 million gallons per year operations and to show that costs for fuel-grade ethanol at 10 million gallons per year are within 10 percent of those of a large-scale (40 million gallons per year) facility. Compact Membrane Systems has established key industrial relationships with both membrane companies and ethanol engineering design firms. These relationships will be helpful in this project and in subsequent commercialization.