ABSTRACT
Biofuels, including corn-based ethanol, can partially meet the increasing demand for transportation fuels. The production of ethanol in the United States has dramatically increased; so too has the quantity of manufacturing coproducts. These non-fermentable residues (i.e., proteins, fibers, and oils) are sold as “distillers dried grains with solubles” (DDGS) and are used to feed livestock in local markets. As the industry grows, the need to ship large quantities of coproducts nationally and internationally has also been increasing. Various processing options offer the potential to increase the economic sustainability of each ethanol plant, and thus the industry overall. However, implementation will be dependent upon how these new costs impact current processing costs. The objective of this study was to model the economics of adding a pelleting operation at a fuel ethanol plant and examine the effects on the transportation and logistics of DDGS, including related cost measures. We have simulated the implications of varying pelleting costs (5–15 $/t) and pelleting rates (0–100%), for a series of DDGS sales prices (50–200 $/t) using modeling and analysis software. The results indicated that, as the proportion of pelleting increases, the cost of transporting DDGS drastically declines, because rail cars can be filled more effectively. At a DDGS sales price of $50/t, 100% pelleting reduces shipping costs for each rail car by 71% compared to shipping the DDGS in bulk form, whereas at a DDGS sales price of $200/t, it will reduce costs by over 91%. Clearly the sustainability of the ethanol industry can be improved by implementing pelleting technology for coproducts.
