Greenhouse gas emissions are an environmental concern and a costly problem for coal-fired power plants, which are facing tighter federal pollution laws. But scientists at Ohio University are looking to nature to develop a cleaner, inexpensive way of removing carbon dioxide from smokestacks.
The researchers, supported by a new $1.07 million grant from the U.S. Department of Energy, are studying how algae and sunlight, in a natural process known as photosynthesis, can absorb some of the carbon dioxide produced after coal is burned. Though other scientists have used lakes filled with algae to absorb gas emissions, the Ohio University team has proposed growing and harvesting the organisms directly in the exhaust gas from power plants.
Algae is not only cheap and plentiful, but could be collected from the power plants for use by agricultural industries, says David Bayless, an assistant professor of mechanical engineering and lead researcher on the project.
"We're storing carbon dioxide in organisms that exist in your backyard," Bayless says. "Once the algae is grown, if it can't be used as fuel or a hydrogen source, it can be used as a fertilizer or soil stabilizer."
The process, he says, would work something like this: As the carbon dioxide exhaust moves toward the smokestacks, it would pass through tubes of running water, creating bicarbonates that would bubble in the water like soda pop. The water then flows through a bioreactor that contains a series of screens on which algae grow. "The algae basically drink the bicarbonates," says Bayless, who also serves as associate director of the university's Ohio Coal Research Center. "They get carbon through this system much quicker than trying to get it out of the air."
Using a system of solar panels, satellite dishes and fiber optic cables developed by scientists at the Oak Ridge National Laboratory, a partner in the project, only visible sunlight would be emitted into the bioreactor, help
Contact: Andrea Gibson