for National Geographic News
As Americans prepare to gobble down 45 million turkeys on Thursday, a factory in Carthage, Missouri, is turning the feathers and innards of the feted bird into a clean-burning fuel oil. Changing World Technologies (CWT), a New York environmental technology company that is behind the project, also has plans to turn the organic waste from chickens, cows, hogs, onions, and Parmesan cheese into light crude oiland those are just the some of CWT's proposed ventures.
The company works such miracles through thermo-depolymerization (TDP), a process by which waste materials are broken down by intensive heat and pressure to produce natural gas, fuel oil, and minerals. The company's CEO, Brian Appel, says he can turn any type of carbon-based wastebe it computers or offalinto combustible fuel. But he admits many people are skeptical.
Any technology that promises to empty U.S. landfills, reduce dependence on foreign oil, and create a clean-burning crude is going to attract naysayers. While presenting New York City officials with a proposal to reform its municipal waste into fuel, one member of the consumer, environmental, and government reform advocacy group NYPIRG (New York Public Interest Research Group) stood up and said, "This guy isn't for real!"
"Afterwards," says Appel, a towering former college basketball player, "I went over and asked her, 'Who are you?' I had never heard of PIRG."
Appel heard from the group again when U.S. PIRG, the national advocacy office of the state PIRGs, mocked Republicans for including a U.S. $3-a-barrel tax incentive for TDP in the now-derailed energy bill. "After including their cash cows and all the polluter pork they could find," said a U.S. PIRG representative, "energy conferees have moved on to tax breaks for turkeys"a $95 million dollar break, by U.S. PIRG accounting.
In actuality, CWT says, TDP would have received only a little more than U.S. $150,000 in credits.
Thermo-depolymerization mimics the Earth's own recipe for fossil fuels, but shaves millions of years off the production time. Wasteturkey guts, for instanceis mixed with water and ground into a thick slurry, which is then heated to 500 degrees Fahrenheit (260 degrees Celsius), pressurized at roughly 600 pounds per square inch (42 kilograms per square centimeter), and cooked for about 15 to 60 minutes until the organic material's molecular structureits polymersbegin to break apart.
Pressure on the mixture is then dropped, releasing steam that is recaptured to power the remaining process. More heat, then distillation, creates the byproductsnatural gas, which is diverted back to fuel the bio-reformer; crude oil, which can be sold to refineries; minerals, to be used in materials like fertilizers; and water.
Barring nuclear waste, anything can yield these goods, according to proponents of the process: 100 pounds (45 kilograms) of tires, for instance, yields 44 pounds (20 kilograms) of oil (along with the other byproducts); a similar quantity of medical waste would result in 65 pounds (30 kilograms) of oil.
Other versions of the process have existed since the 1970s, but only Appel's addition of water and pressurizationinstead of incineration, for examplehas made the process environmentally friendly and, he claims, 85 percent energy efficient. "For every 100 Btus of energy in the waste that's used, only 15 Btus are needed to power the process," Appel said.
Some find that rate hard to believe. Immediately after a Discover article on TDP appeared in its May issue, bloggers began criticizing Appel's math online. To date, no study of his figures has appeared in an independent, peer-reviewed journal, a sure way to verify his claims. Appel says enough scientists have reviewed his technology, including Jeff Tester, a chemical engineer at MIT who acknowledged in MIT's Technology Review "They have certainly produced the products they've claimed at a smaller scale," but it remained to be seen whether the same results could be replicated at Carthage.
Appel received U.S. $5 million from the EPA to build the $20-million dollar Carthage facility it jointly owns with ConAgra, one of North America's largest packaged food companies. At full capacity, the plant is designed to turn 200 tons of turkey guts into 500 barrels of oil a day. If it performs as expected, proposed plants in Nevada, Colorado, Alabama, and Italy will also get off the groundand make the oil more competitively priced. Appel estimates he would need around a few dozen plants in operation to put the cost of producing the oil at around $10 a barrel. The price could drop further as more plants are built, he says.
SOURCES AND RELATED WEB SITES