Fill 'er Up With Corn

Ethanol is becoming a component in an increasing amount of the nation’s fuel supply. Those who manufacture and sell it and the associations that represent them hail ethanol as the reducer of and, ultimately, the means for ending the nation’s dependency on foreign oil.

In late February 2008, Bob Dinneen, president and chief executive officer of the Renewable Fuels Association (RFA) told those attending the association’s annual National Ethanol Conference that the U.S. ethanol industry is bringing about “revolutionary” change.

“Ethanol is now a ubiquitous component of the U.S. motor fuel supply, blended in more than 50 percent of the nation’s gasoline and will very soon be in virtually every single gallon of gasoline sold from coast to coast and border to border,” said Dinneen in his 2008 State of the Ethanol Industry Address. “The 6.5 billion gallons of ethanol produced in 2007 displaced America’s need for 228 million barrels of oil, saving more than $15 billion, or $45 million a day.”

Ethanol’s revolution isn’t limited to motor fuels, Dinneen said. With corn being the primary feed stock currently used to produce ethanol, production already has made a significant impact in areas that have depended on traditional agricultural economies.

“The [ethanol] industry is reshaping our rural landscape, revitalizing communities, and providing the most significant value-added market farmers have ever had,” he said.

That impact comes from operation of 143 biorefineries in 22 states with a collective capacity of 7.9 billion gallons per year. Twenty-nine of these plants opened in 2007, increasing production capacity by 32 percent. Sixty additional biorefineries currently are under construction with seven existing plants undergoing expansion. In addition, 57 new plants are under construction.

Ethanol plant construction projects represent significant opportunities for electrical contractors to do industrial work projects, especially those located or doing business in the Midwest. Plants are generally located near readily available corn supplies.

For example, Kansas is the nation’s third-leading producer of ethanol, and currently there are 11 dry-mill ethanol plants operating in the state with three more under construction, two projects nearing start of construction, and 10 more under consideration.

Ethanol construction

Shelley Electric, Wichita, Kan., has experience on three Kansas ethanol plant construction projects. The company, one of two electrical contractors on a completed 110-million-gallon-per-year (mgpy) ethanol plant in Liberal, currently is working with another contractor on a 10-mgpy facility in Scandia and is the sole electrical contractor for construction of a 55-mgpy plant now under construction in Lyons.

Ethanol plant construction projects usually have very aggressive completion dates and, therefore, demand large numbers of skilled electricians, said Tom Zoglmann, Shelley project manager.

“Electrical work is similar to that of a refinery, but much cleaner,” Zoglmann said. “With just grain and water involved, it’s obvious the work will be cleaner than handling crude oil and its byproducts.”

Shelley Electric’s three ethanol plant projects all use the dry-mill process for producing ethanol, the method used for more than 80 percent of ethanol production.

In the dry-milling process, whole corn kernels or other starchy grain is ground into meal and mixed with water to form a mash slurry. The addition of enzymes converts the starch to dextrose, a simple sugar. The addition of ammonia controls acidity-alkalinity balance and serves as a nutrient to the yeast that will be added later.

The mash is processed in high-temperature cookers to reduce bacteria levels before the fermentation process. Next the mash is cooled and transferred to fermenters where yeast is added, and the conversion of sugar to ethanol and carbon dioxide (CO2) begins.

Fermentation requires from 40 to 50 hours while the mash is agitated and kept cool to facilitate activity of the yeast. After fermentation, the resulting “beer” is transferred to distillation columns where the ethanol is separated from the remaining “stillage,” residue composed of nonfermented solids and water.

The ethanol is concentrated to 190 proof by conventional distillation, then is dehydrated to approximately 200 proof in a molecular sieve system.

The anhydrous ethanol then is blended to make it approximately 5 percent gasoline, making it undrinkable and not subject to alcohol beverage taxes.

The finished ethanol then is shipped in tank trucks to gasoline terminals or retailers. (This simplified description of the dry-mill process is summarized from information from RFA.)

Byproducts of the process are not wasted. The CO2 released during fermentation is captured and sold for carbonating soft drinks and beverages and for use in manufacturing dry ice.

Stillage is sent through a centrifuge separating the coarse grain from the solubles. The solubles then are concentrated by evaporation, resulting in a syrupy solution. The coarse grain and syrup are dried together to produce livestock feed.

What’s electrical about it?

The electrical work is varied in ethanol plants, and it is good work for those ECs that can get it. Zoglmann detailed the electrical work required for the 55-mgpy plant in Lyons.

“The project requires two 600-amp, 15-kV loops to provide power to the plant,” he said. “There are two 3,000-amp, 480-volt main switchboards that feed the process area, two 3,000-amp, 480-volt main switchboards to feed the energy center, and one 3,000-amp, 480-volt main switchboard for water treatment equipment.”

In the grain-handling portion of the plant, large, 350-

horsepower hammer mills grind the corn. The process area has pump and agitator electric motors ranging from .5 to 150 horsepower, and the energy center requires electric motors ranging from 3 horsepower for the conveyor system to the 350-horsepower boiler fan motor.

The water treatment area has .5-horsepower pump motors with 250-horsepower pump motors for the cooling tower.

“All motors in the facility are 480-volt, except the chiller, which is fed 4,160 volts. Larger plants use 4,160 volts for cooling tower pumps,” Zoglmann said.

A full tank of opportunities

Advocates for the continuing and increased use of ethanol fuels have every reason to be optimistic. Passage late last year of the federal Energy Independence and Security Act of 2007 couples increased vehicle fuel consumption efficiency with increased use of fuels containing renewable constituents and will usher in a new energy era in America, the RFA’s 2008 outlook report states.

“The law,” states the report, “increases the Renewable Fuels Standard (RFS) to 36 billion gallons of annual renewable fuel use by 2022. And by requiring that nearly 60 percent of the new RFS be met by advanced biofuels, including cellulosic ethanol, it paves the way for commercialization of these vital next-generation ethanol technologies.”

However, as with any industry, there are issues to address.

The ripple effect of a worsening general economy can impact this industry as it does most other. In its March 2008 issue, Ethanol Producer magazine reported rising construction costs, high feed stock prices, and a sputtering economy were factors in several planned ethanol plants being dropped.

The opposition

There are critics who question whether costs to produce ethanol justify industry claims about its benefits, citing the cost of using natural gas and electricity produced by the use of fossil fuels to produce each gallon of ethanol negates any savings in oil usage.

Furthermore, ethanol is not transported by pipelines, but by truck, train or ship, all of which burn fuel, making costs to move ethanol higher than gasoline and other petroleum-based energy products. Ethanol fires following accidents earlier this year drew attention to the fact that burning ethanol is more difficult to extinguish than gasoline and requires a special foam, which many fire departments either don’t have or lack a sufficient supply of for a large fire.

Yet, with the 2007 Energy Act in place, the RFA and other well-financed national organizations, such as the American Coalition for Ethanol, American Farm Bureau Federation and the National Corn Growers Association (NCGA), supported by numerous state associations, are aggressively responding to these and other questions.

To the contention that ethanol takes more energy to produce than it contributes, the NCGA responds that the viewpoint is based on data that includes costs of energy required to plant, grow and harvest the corn, in addition to that needed to produce ethanol, and that the net energy balance of ethanol production is improving because production is becoming more efficient. The association said one bushel of corn today yields 2.8 gallons of ethanol, an improvement over just a few years ago.

Along with others, the NCGA refutes objections that ethanol production wastes corn that could be used to feed hungry people. The association said that there is an ample supply of corn for both food and ethanol production, and most corn used in ethanol production is of varieties used to feed livestock.

Advances in technology that allow ethanol to be produced from cellulosic feed stocks also will be used for ethanol production. The American Coalition for Ethanol said technology is available today to make ethanol from corn stalks; grain straw; rice hulls; sugarcane bagasse; native grasses, such as switch grass; wood chips; or even municipal waste.

As more cellulosic sources are used to make ethanol, the food-for-fuel argument likely will become less compelling.

GRIFFIN, a construction and tools writer from Oklahoma City, can be reached at 405.748.5256 or up-front@cox-net.



About the Author

Jeff Griffin

Freelance Writer
Jeff Griffin, Oklahoma City, is a construction journalist specializing in the electrical, telecommunications and underground utility construction industries. Contact him at .

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