Algae, the simple, one-celled organism, hides a surprisingly “green” elegance: It converts to biodiesel fuel and it cleans the water in which it grows.
Researchers at RIT are testing the commercial viability of algae as a multi-tasking green technology that small towns could adopt.
“Rural communities don’t always get the benefit of green technologies,” says Ali Ogut, professor in the Department of Mechanical Engineering at RIT and president and CTO of Environmental Energy Technologies Inc. “If we can prove there is commercial potential, then I think we could approach small towns with wastewater treatment plants to consider using this technology to treat their wastewater and then process the algae.”
Jeff Lodge, associate professor of biological sciences, sees a clear niche for this technology. “If a small town can put out a much cleaner product that won’t contaminate the land and people’s well water, and that can be converted to biodiesel to fuel the town’s trucks—that’s a win, win, win.”
Lodge and Eric Lannan, a mechanical engineering graduate student from Columbus, Ind., have spent the last two years growing algae in wastewater in the lab. Lannan, who will earn his master’s degree this spring, wanted to explore the aquatic plant’s potential as an alternative fuel.
The traditional way to grow algae in a laboratory uses a synthetic solution enriched with nitrogen and phosphates. The algae consume the chemicals and produce lipids, or fats. Not all algae strains are the same. And not all produce lipids with the right kind of carbon chains that yield valuable oil, such as biodiesel.
Using wastewater instead of a synthetic medium eliminates the steepest cost in the algae-production equation. According to Lannan, the chemical solution alone can account for as much as 70 percent of the cost of biodiesel.
“You can stick algae in a pond and it grows on its own,” Lannan says. “You get a lot of upstream costs when you’re making synthetic media on a large scale. The cost is the production of all those nutrients that you’re adding to the solution and related transportation costs.”
Opting for wastewater bypasses the need to supplement purified water; it’s dirty upon arrival. And the algae strains Lodge and Lannan are using—Scenedesmus, Chlorella and Chlamydomonas—like it that way.
“Algae will take out all the ammonia—99 percent—88 percent of the nitrate and 99 percent of the phosphate from the wastewater,” Lodge says. “We’ve got data to show that the coliform counts are dramatically reduced below the level that’s allowed to go out into Lake Ontario.”
“Our original goal was not cleaning wastewater,” notes Ogut, Lannan’s thesis advisor. “We are using algae as a feedstock for making oil. Determining that it also cleans wastewater is a big plus. It’s a great result.”
“Wastewater is cheap, abundant and we knew where we could get it,” he says.
Ogut’s connections with Monroe County led the team to the Frank E. Van Lare Wastewater Treatment Plant in Irondequoit, which was happy to accommodate them. At first, Lodge and Lannan showed up with jugs to fill the small tanks at the lab—eight gallons in all. Now they are filling a 100-gallon tank at Environmental Energy Technologies, an RIT spinoff Ogut launched in 2004.
In May, Lodge and graduate student Christina Karas, who has transitioned into the project as Lannan writes his thesis, will take the experiment outside. They will move the 100-gallon tank to the parking lot behind the building to grow algae under sunlight. If Lodge and Karas can cultivate it in large quantities, they’ll be ready for the next challenge: replicating their success in a 1,000-gallon pond at the Van Lare Wastewater Treatment Plant.
One thousand gallons is the magic number for Ogut. Reaching that volume will predict algae’s commercial potential, he says.
“The question is, ‘Does our algae, which does a great job at cleaning wastewater, make great oil?’” asks Ogut. “If the answer is ‘yes,’ then we’ve got something.”
Web extra: To hear more about RIT’s research associated with algae, scan the QR code to the left with your smartphone or mobile device, or visit www.thetigerbeat.com/rss/podcasts/eric_lannan.mp3