Ins and outs of ethanol in Meade County By SANDRA STONE One customer – the Meade County Riverport Authority – was already on board before the 551-acre parcel adjacent to Arch Chemicals was purchased late last year for the purpose of developing an industrial park. Another customer – AgriFuels, LLC – was already expressing interest. Now, approximately eight months later, plans are in the works for AgriFuels to purchase a portion of this land for the purpose of building a 55 million-gallon ethanol plant. Preliminary design of the plant is slated to begin this fall. Several articles about the proposed ethanol plant have appeared in the Messenger, but questions still arise. What is ethanol? What effect will an ethanol plant have on Meade County? How many jobs will it bring to the community? Will the plant affect our air quality? What’s in it for us? Beginning this week, let’s take a closer look at some of these questions. Let’s start with the most basic question. What, exactly, is ethanol? Ethanol is grain alcohol, produced from crops such as corn or sugar. It is a clean-burning, high-octane fuel that is often blended with unleaded gasoline for several reasons. It decreases the cost of gas, making that trip to the pump a little less painful. It increases the octane of gasoline, resulting in better performance. And it decreases emissions from the vehicle (fewer emissions, cleaner air). Ethanol is produced from a corn kernel or other starchy grain that is first ground into flour called meal. The meal is then mixed with water to form a mash. Enzymes, water and ammonia are added in a high-temperature cooker that produces a mash. (Moonshiners from back in the day are probably wondering when we’re going to tell them something they don’t know.) The mash is then cooled and transferred to fermenters where yeast is added and the conversion of the mash to ethanol and carbon dioxide (CO2) begins. The fermentation process, which usually takes 40 to 50 hours, produces a beer like any brewery would produce. After fermentation, the resulting beer is transferred to distillation columns where the ethanol is separated from the remaining mash. The ethanol is concentrated to 190 proof then dehydrated until it reaches about 200 proof. At this point, the ethanol, which is essentially pure alcohol, is blended with about five percent natural gasoline to make it undrinkable. The byproducts of this process are also utilized. The remaining mash is sent through a dryer that produced dried distillers grains with solubles (DDGS), a high-quality, nutritious livestock feed. The CO2 released during fermentation is captured and sold for use in carbonated beverages, welding supplies and the manufacturing of dry ice. As for concerns about air quality or noxious odors, emissions will be controlled by a closed loop system that captures all particulate matter and odors. The system, a thermal oxidizer, recycles all emission through a high temperature process (essentially burning it off before it reaches the air). In the past, ethanol plants have been known to give off some emissions of particulate matter, but most ethanol plants, including AgriFuels, are classified as minor emissions sources by the United States Environmental Protection (EPA).
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