Let algae do the dirty work.
Researchers at Rochester Institute of Technology are developing biodiesel from microalgae grown in wastewater. The project is doubly "green" because algae consume nitrates and phosphates and reduce bacteria and toxins in the water. The end result: clean wastewater and stock for a promising biofuel.
The purified wastewater can be channeled back into receiving bodies of water at treatment plants, while the biodiesel can fuel buses, construction vehicles and farm equipment. Algae could replace diesel's telltale black puffs of exhaust with cleaner emissions low in the sulfur and particulates that accompany fossil fuels.
Algae have a lot of advantages. They are cheaper and faster to grow than corn, which requires nutrient-rich soil, fertilizer and insecticide. Factor in the fuel used to harvest and transport corn and ethanol starts to look complicated.
In contrast, algae are much simpler organisms. They use photosynthesis to convert sunlight into energy. They need only waterponds or tanks to grow insunlight and carbon dioxide.
"Algaeas a renewable feedstockgrow a lot quicker than crops of corn or soybeans," says Eric Lannan, who is working on his master's degree in mechanical engineering at RIT. "We can start a new batch of algae about every seven days. It's a more continuous source that could offset 50 percent of our total gas use for equipment that uses diesel."
Cold weather is an issue for biodiesel fuels.
"The one big drawback is that biodiesel does freeze at a higher temperature," says Jeff Lodge, associate professor of biological sciences at RIT. "It doesn't matter what kind of diesel fuel you have, if it gets too cold, the engine's not starting. It gels up. It's possible to blend various types of biodieselalgae derived with soybeans or some other typeto generate a biodiesel with a more favorable pour point that flows easily."
Lannan's graduate research in biof
|Contact: Susan Gawlowicz|
Rochester Institute of Technology