Dalton utilities experiments with algae to treat wastewater, produce fuel

Dalton utilities experiments with algae to treat wastewater, produce fuel

June 29th, 2009 by Kelly Jackson in News

DALTON, Ga. -- Dalton Utilities is going green with something that is green -- algae.

The company has partnered with the University of Georgia for the past two years on pioneering research for using algae to treat wastewater and produce fuel.

"We'd been hearing about people trying to work with algae to produce biodiesel," said Mark Marlowe, vice president of wastewater engineering for Dalton Utilities. "We decided to talk to the University of Georgia about partnering on a project that would benefit us from the standpoint that it would treat the wastewater to a higher standard and that it had potential to produce a biofuel that we might be able to utilize in our operation."


The process of making biodiesel from algae involves:

* Oil is extracted from the algae

* Oil is refined, basically a filtration process

* Clean oil is mixed with alcohol and a catalyst

* The three react to produce biodiesel

Source: K.C. Das, University of Georgia

Dalton Utilities has a 9,000-acre land application system off the South Bypass. Treated wastewater is sprayed on soil at the site to remove remaining nutrients such as phosphorus before the water enters the Conasauga River. Mr. Marlowe said the company has determined through soil testing that the soil is reaching a concentration level that will not allow it to absorb phosphorus for many more years, so officials began looking at ways to continue using the existing site without relying on expensive chemicals for phosphorus removal.

Initial research with the university has shown successful results for using algae to remove these nutrients from wastewater at the Dalton Utilities site and produce fuel, he said.

Mr. Marlowe said university researchers isolated naturally occurring strains of algae from the wastewater. Those strains were cultivated in university labs to determine which would be the most effective at removing phosphorus and producing oil for biodiesel and which would best flourish in an outdoor environment, according to K.C. Das, director of UGA's biorefinery and carbon cycling program. They've identified six organisms they'll use for further testing at a one-acre pilot facility Dalton Utilities plans to start building this winter, he said.

Mr. Marlowe said the ultimate goal is to build a full-scale facility of 20 to 40 acres that could treat much of the wastewater sprayed on the site, which is 25 million to 35 million gallons per day. The full-scale operation has the potential to produce 260,000 gallons of biodiesel per year, enough to fuel the Dalton Utilities diesel fleet, he said.

Algae also feed off carbon dioxide, so the company is looking at the potential to pipe carbon dioxide emissions from its nearby power plant into the wastewater to be absorbed by the algae. Dalton Utilities will receive renewable energy credits as these plans come into play, Mr. Marlowe said.

The use of algae for fuel is a developing technology, but it shows promise because it doesn't compete with space needed for food crops and produces a higher yield than other crops used for alternative fuels, according to Mr. Das.

He said algae has the potential to produce up to 2,000 gallons of oil per acre per year. By comparison, a soybean crop can produce up to 75 gallons of oil per acre per year, he said.