Algae Provide Clean Water Solution
Don’t underestimate the power of algae. The single-celled organism often associated with pond scum is also a microscopic water filter. Alison Chan, a wastewater engineer based in Fresno, California, is working on a pilot project on the effectiveness of algae in treating wastewater at a winery. “The goal is to reuse 100 per cent of their water for irrigation in the vineyard,” says Chan, M.A.Sc. ’10. Aside from turning wastewater into clean water, the algae can also be used as fertilizer or feedstock for farms, she adds.
Nitrogen and phosphorus can harm the environment and must be removed from wastewater. Ammonia is toxic to aquatic organisms and removes oxygen from water, making it uninhabitable. When wastewater is discharged without being treated properly, it can cause thick layers of “algae bloom” to form in lakes and ponds, an indication that the body of water is dying. “Oxygen can't get through; sunlight can't get through. Basically, it kills the ecosystem,” says Chan. The winery is also interested in removing potassium from its wastewater, since the element can affect the flavour of its wine.
Chan did her undergrad in chemical engineering at the University of Waterloo before coming to Guelph to study environmental engineering. For her master’s thesis, she studied the use of algae in wastewater treatment facilities, a practice used on a small scale in some municipalities. Chan says wetlands often serve as natural wastewater purifiers in developing countries. Living in a state where water is scarce, she says California has stringent regulations for conserving and protecting its water supply.
“I'm really interested in water,” she says. “I think it’s a very valuable resource and it's not something we can just overlook in the years to come.” Once the project is complete, Chan says, she hopes to work with industrial wastewater.