27    WASTEWATER PROFILE OF AN ETHANOL PRODUCTION
FACILITY
Kurt W. Anderson, Environmental Supervisor
Dave Szumski, Environmental Technician
New Energy Company of Indiana
South Bend, Indiana 46680
John F. H. Walker, Senior Staff Environmental Engineer
Davy McKee Corporation
Chicago, Illinois 60606
INTRODUCTION
Little published information exists regarding actual operating experience of a major dry-milling-
based fuel alcohol plant which would assist the designer or operator of such a plant in developing
those modifications that could accomplish desired reductions in overall wastewater loads. It is hoped
that this paper will both provide some assistance in these matters and encourage other major fuel
alcohol producers to share their experience.
In a time of increasing surplus crop reserves, dwindling fuel resources, widening foreign trade
deficits, and record unemployment, the federal government established a new and progressive program, the Alcohol Fuels Program. The program was intended to create a renewable fuel source,
reduce foreign trade deficits, stabilize the agricultural market, provide a more environmentally
acceptable fuel source, create new jobs, and reduce American dependence on foreign oil. As Barry
Commoner put it ... . "If the government, instead of seeking to reduce agricultural output, were to
facilitate the introduction of a crop system capable of producing ethanol as well as food, and suitably
integrated with the necessary changes in the oil and automobile industries, farmers would be better
off, and the nation would be on the way to a more stable, solar economy."
The New Energy Company of Indiana was formed to play an important role in this new ethanol
industry. New Energy Company of Indiana operates a new 60-million-gallons-per-year grassroots
production facility in South Bend, Indiana. Design of this facility has incorporated some of the latest
technological innovations to ensure efficient and reliable production. The New Energy plant processes
more than 22 million bushels of corn per year to produce alcohol, carbon dioxide, and animal feed.
The facility has brought over 1,000 new jobs to the state and added needed dollars to the local tax
base. The future of this new industry, and the rewards to be realized by the American people, are
dependent upon facilities such as the one operated by the New Energy Company.
Process Description and Wastewater Sources
The most common method of producing ethanol-for-fuel begins with conversion of starchy materials to sugars by a process known as saccharification. These sugars are then converted to alcohol via
fermentation. The choice of feedstock is dependent upon availability, economics, and byproduct
recovery. Corn is the most common feedstock in the United States being widely available, economically feasible, and producing a high quality animal feed byproduct.
Corn-based ethanol plants are of two basic types, wet corn milling and dry corn milling. Most wet
corn milling plants were established originally for the production of other types of corn products but
have been converted to the manufacture of ethanol-for-fuel as that market has developed. The New
Energy Company plant was created expressly for the manufacture of ethanol-for-fuel and is based on
a dry corn milling process.
In a modern dry corn milling facility, manufacturing ethanol from corn begins with the grinding of
the feedstock in hammermills. Grinding reduces the size of the raw material and breaks up the outer
cellulosic wall, making the interior starches more accessible to saccharification. The ground corn is
then mixed with water to form a slurry or mash. This mash is then cooked to solubilize the starches.
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