Adding to that momentum is the Energy Independence and Security Act of 2007 that President Bush signed into law just before Christmas. Although the act falls short of the President’s original proposal to Congress to reduce oil consumption by 20 percent over 10 years, it does set aggressive targets. The renewal fuel standard set by the law, for example, will require fuel producers to use at least 36 billion gallons of biofuels in their products by 2022.

“This is nearly a fivefold increase over current levels,” said the President during the signing ceremony at the Department of Energy. “It will help us diversify our energy supplies and reduce our dependence on oil.”

Tooling up

 Satisfying the expected surge in demand for biofuels will require a combination of reliable automation and technologies to extract more fuel from natural resources. The ethanol industry is already tooling up for the challenge on both fronts. One such tool is the National Corn-to-Ethanol Research Center, which opened its doors on the Southern Illinois University’s campus in Edwardsville in 2003. This Center is helping the industry to make existing processes for producing ethanol more efficient and to commercialize new technologies.

The Center also trains the workers needed to operate the growing number of biofuel facilities being built throughout the country. Classes range from one-hour seminars to five-day courses for operators and executives. In fact, the Center trained 45 displaced autoworkers from Michigan in two sessions in January and March last year.

More trained workers are needed, however. “Right now, there are about 130 to 135 ethanol plants already operating,” says Don Mack, biofuels initiative lead for the Process Automation Systems Group at Siemens Energy and Automation Inc., in Spring House, Pa. “Another 60 or so are being built.”

Mack works with the Center because Siemens formed a 10-year partnership with it last year. Since then, the automation supplier has donated hundreds of thousands of dollars in Simatic PCS 7 distributed-control equipment, instrumentation, software and configuration services. The Center accepted the gift because Siemens’ automation is the most commonly used technology in ethanol plants today. Of the nearly 200 that are already operating or are being built, over half are using it, according to Mack.

Smart fieldbus technology, such as Profibus, has caught on in this industry in a big way because it requires much less time and cost to install, commission and maintain. “A characteristic of the ethanol industry is that it contains a lot of greenfield plants,” explains Mack. These new plants do not have to overcome the same barriers that their already established counterparts in other industries face. So, they find it easy to adopt the technology from the start.

Rip and replace

This, however, doesn’t mean that ethanol plants won’t rip out technology when it gets in the way of satisfying the growing demand for their products. The Golden Triangle Energy Cooperative, in Craig, Mo., did just that last year when it replaced its old control system with a ControlLogix programmable automation controller from Milwaukee-based supplier Rockwell Automation Inc.

The cards in the old system were just that—old. “We got notification from the vendor that it wasn’t making the cards any more,” says Roger Hill, general manager at Golden Triangle and 30-year veteran of the ethanol business. Although the vendor would repair the cards, “we got to a point where it wasn’t supporting us as we needed.”

His highly automated facility needs attentive support because ethanol production must continue around the clock, except for the scheduled shutdowns that occur every six months or so. Only two operators control the production of 20 million gallons of ethanol a year. Process controllers oversee every aspect of the plant, from the time that the trucks dump the grain into the bins to the time that ethanol leaves the plant.

Corn from the bins is ground into flour, hydrated in a jet-cooker, and converted into sugar with enzymes that are metered into the process. Yeast added to the four 300,000-gallon stills ferments the sugar, transforming it into 15 percent to 17 percent alcohol in a continuous-batch process. Then, a series of distillation towers, flash evaporators and molecular sieves strip the water from the ethanol.

Meanwhile, the residual mash at the bottom of the stills goes to one of three centrifuges, which spin at 3,550 revolutions per minute (rpm) to separate the solids from the water. Another set of evaporators condenses the liquid further so that the solid material can be sold as a livestock feed additive. ...