Fuel from foul
Using food and crop residues, a new breed of entrepreneur looks to cut waste and create energy
ST. LOUIS AND BOSTON — Forget Iraq, OPEC, and that Alaskan wildlife refuge for the moment. Some of the clues to the world's energy future may lie on your dinner plate.
The plants that grew the rice you're eating also produce rice straw, which is mostly burned today but could be turned into fuel. Corn already produces ethanol, but stalks left in the field have energy potential. And all the country's millions of pounds of leftover chicken and turkey bones could produce millions of barrels of crude oil. The turkey experiment is already under way.
For decades, scientists have worked to turn trash into energy: wood into gasoline and municipal waste into industrial fuel. Some ventures worked; others proved too expensive or unwieldy. Now, a new generation of entrepreneurs is trying to turn the nation's muck into black gold. Armed with better technology and understanding, they're making promising starts.
These conversions, if done correctly, could not only bolster the United States' energy reserves, they could cut its leading sources of waste, starting with the nation's farms.
"We're held hostage by troubles in Venezuela, by uncertainty in Kuwait," says Brian Appel, CEO of Changing World Technologies (CWT), a New York environmental technology company. "Let's take advantage of all this waste and make a product we really need."
CWT has made perhaps the biggest splash by teaming up with food production giant ConAgra Foods Inc. Later this month CWT's $25 million turkey-to-oil processor will start turning wastes from ConAgra's Carthage, Mo., plant into light crude oil and other products.
Jeff Tester, a chemical engineering professor at Massachusetts Institute of Technology (MIT) in Cambridge, has visited a CWT pilot plant in Philadelphia and is intrigued by the technology's potential. "This is a good example of a win-win situation," he says. "It's not necessarily the holy grail, but it's an innovative idea."
Using a process called thermal depolymerization, which breaks down organic compounds with water and heat, CWT can make fuel from fowl - or corn waste or municipal sludge, for that matter. The Carthage plant, which will process about 200 tons of animal waste daily, is expected to pump out some 7.6 million gallons of bio-derived oil in its first year.
That's tiny - about the size of a Texas wildcatter's well - even compared to the 2.7 billion gallons of ethanol the US expects to produce this year, largely from corn. But that industry receives government subsidies - something Mr. Appel doesn't receive. At the moment, it costs $15 per barrel to produce oil from the Missouri turkey plant, and costs could drop below $10 as more plants go up, he says. That would put his reprocessed oil on par with conventional drilling costs, roughly between $5 and $13 a barrel.
"Right now the margins are tight," Appel says. "If we really want to reduce [US] dependence on [foreign] oil, we need help to grow more quickly."
The company is also negotiating contracts to recycle municipal sludge, solid waste, and other materials.
Meanwhile, DDS Technologies, a European environmental technology company, is bringing another new waste-recycling system to the US. Already in use by several major Italian companies, the process reuses all the elements of the material it recycles, making it much more efficient than most primary food processors.
"When I look at some of the processes we use to make foods, they're archaic," says the company's COO Kerin Franklin. "The process for making soy milk, it must have been invented by a couple of hippies 20 years ago. You wind up throwing a lot away."
DDS takes all that trash and breaks it down into small enough bits to render it useful on many levels. Take pomace, the stuff left over when oranges and other fruit are squeezed for juice. Currently, fruit processors pay roughly $40 a ton to other companies to haul away the pomace, which they turn into livestock feed. DDS can take the same waste and harvest pectin (used in yogurt, gelatin, marshmallows, and fruit snacks), flavor substitutes (used in baking and animal feed), fiber (used in cosmetics production), and essential oil of orange (used as a flavoring). "Our goal is zero left over,"Ms. Franklin says. "The entire waste stream is utilized."
The US branch of DDS, based in Boca Raton, Fla., hopes to start making use of its innovative air-pressure technology later this year. By accelerating particles of matter then suddenly stopping them, DDS can separate their components much the way a speeding motorcycle, suddenly stopped, would send first the rider's helmet, then the rider, then the bike itself flying through the air.
The company is already working with a major US cityto handle its municipal sludge, and has just signed a 10-year joint venture with biomass-to-ethanol company Xethanol to convert sewage into the sugars used in ethanol production. Because DDS's process uses air and not physical contact with the material, Franklin says, it can assure a higher level of purity than other systems.
While reprocessing agricultural waste has huge potential, no one knows how huge. In a Foreign Affairs article earlier this year, Timothy Wirth, president of the United Nations Foundation, and two coauthors estimated that available agricultural waste could produce 10 times the ethanol that corn does today. But it's unlikely all of it will be reused for energy. Every year some of it gets plowed under, some gets burned, some gets thrown away. Much of the rest - 45 million tons, enough to cover the entire Washington, D.C., area in 17 inches of muck, according to the American Feed Industry Association - is reprocessed into animal feed.
Clearly, if environmental rules continue to stiffen, farmers will be casting about for new solutions. For example: federal regulations ban the burning of rice straw (the detritus left over after harvest) by mid-decade. So the industry is looking for ways to reuse the straw, including ways to process it into energy. Entrepreneurial firms such as CWT and DDS see potential. But some analysts believe such efforts will require federal help to blossom. "There's the potential to accelerate this much, much faster, if this country applies the same sort of aggressive approach we've taken to finding oil," says Dr. Tester of MIT. "But you have to learn by doing it."