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Wednesday, Aug. 22, 2007 04:54 am

Energy hogs

Illinois scientsts get the poop on pig power

Untitled Document Yuanhui Zhang knew that some people would pooh-pooh his research proposal to take the stink out of hog manure 11 years ago. He’s heard every joke and pun in the book, but Zhang is able to keep his sense of humor, partly because he realizes that the potential value of his research goes beyond cheap punch lines. Using a technique he developed known as thermochemical conversion, Zhang, a professor of agricultural and biological engineering at the University of Illinois at Urbana-Champaign, initially believed that he and his research team could eliminate the environmental pollutants and odors associated with storage and disposal of liquid animal waste on large concentrated animal-feeding operations. In short, he thought he could turn something that smells awful into products that have no smell. He was thinking about something like odorless fertilizer, but he may have stumbled on something much more valuable. “We are turning so-called waste material into something useful,” Zhang says.
Human greed is the very thing that has fueled interest and helped Zhang narrow his research. Consider that a barrel of crude oil in 1996, when Zhang began his research, traded for around $22 a barrel; today oil costs more than $70 per barrel. Furthermore, world oil consumption is expected to grow to 118 million barrels per year by 2030, and increasing demand for fossil fuels in developing nations such as China and India, which combined represent more than two-fifths of the planet’s population, continues to drive up energy costs. To combat the inevitable petroleum shortfall and cut back on U.S. dependence on the earth’s finite supply of petroleum, energy experts believe that developing renewable sources of fuel, particularly on Midwestern farms, is key. National security and environmental concerns aside, swine-manure conversion appeals especially to hog farmers, who fork over billions of dollars each year to have the smelly pits located beneath their pig pens pumped. Zhang takes it off their hands for free. His researchers collect manure — the fresher the better, he says — and haul it back to the lab, where it’s dumped into a pressure cooker for 40 minutes to squeeze out a dark, viscous substance that, molecularly, is almost identical to the black stuff that sent Jed Clampett’s family to Beverly Hills. Thermochemical conversion mimics the process by which nature produces oil, substituting swine manure and laboratory equipment for the remains of dinosaurs, saber-toothed tigers, cave people, and prehistoric plants, which are heated and pressurized over millions of years. The process yields five parts: one is oil and the remaining four are wastewater, which retains 95 percent of the fertilizing capability of the original manure. Net energy balance is another plus. According to the researchers’ calculations, three parts come out for every unit of energy that goes in. Compare that to the output of corn ethanol, which, depending on whom you ask is closer to 1.0 — or, some scientists say, a negative balance. One 250-pound hog can produce as much as 15 gallons of oil, adding approximately $10 of profit per animal. One half-gallon batch of manure converts to about 9 ounces of a No. 6 heating oil that retains no trace of manure odor. Naturally the research has drawn a flurry of attention from the commercial interests, and businesspeople are helping Zhang with the next step: nailing down the economics of larger-scale production. Otis Jessee, a principal with Jefferson City, Mo.-based Worldwide BioEnergy, bought the exclusive license to Zhang’s technology and is working on building a pilot plant. He has plans for a 1,000-square-foot facility located near a 5,000-head hog farm, most likely in southeastern Missouri. Jessee, a semiretired engineer, has given $200,000 over the past years to underwrite some of the costs and has agreed to pay a 3 percent royalty back to the University of Illinois. He estimates that construction could begin in three months and that the poop plant could be pumping out petroleum within a year.
“There is a lot of potential, but we’re just trying to do it on a small scale,” Jessee says. “We’re also going to do human waste.”

Bioenergy was everyone’s mind at this year’s Agronomy Day, held in Urbana. In addition to swine manure, tours focused on biodiesel, wind power, miscanthus, and switchgrass. “We’re not here to bash corn; we’re not here to bash trees. It’s all going to be part of the answer,” says Frank Dohleman, a researcher studying miscanthus and switchgrass.
Hans Blaschek, director of the U of I’s Center for Advanced BioEnergy Research, says that the environment has taken center stage in recent years. “Yes, it’s true that high oil prices have been driving a lot of the interest,” Blaschek says, “but I think people are concerned today more about the environment more than they ever have before, and renewable bioproducts offers us an opportunity to do things that are sustainable.”
Just look at how far ethanol has come since the national energy crisis of three decades ago, he says. Blaschek acknowledges that the debate over whether crops should be used for fuel or food will continue to be waged into the future, but he suggests that that the future for bioenergy and Illinois agriculture remains bright: “Some people think it’s like a dot-com event or something, but let me suggest to you that this is not going to be a flash in the pan.”
Ethanol critics call the fuel a boondoggle because the planet’s energy needs would not be met even if corn covered every acre of Earth.
Certainly the same holds true for hogs, but Zhang agrees with Dohleman’s assessment that biofuels research is aimed to augment, not immediately replace, oil. Zhang asks the American public to have patience with researchers. Next he wants to develop and optimize a continuous thermochemical conversion process that turns the swine manure into a liquid biofuel. He’s hoping that one day lawmakers in Springfield will realize the value in funding cutting-edge biofuels research like his.  “I hope our state leaders are listening. We just don’t have as much support as other Midwestern states, in my opinion,” presumably because of the Chicago-centric nature of the Illinois legislature, he says. “The engineering part we need to perfect, and we need to learn more about the chemistry. Manure itself is very complicated.”

Contact R.L. Nave at rnave@illinoistimes.com.


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