Humans produce a lot of wastewater, and treating it can be laborious, energy intensive and expensive. In one part of the treatment process, for example, wastewater is churned in aeration tanks, which provide oxygen to microorganisms that extract nitrogen pollution from the water. The process of aerating microorganisms, however, requires a lot of energy.
NSF-funded researchers from Columbia University’s Engineering School are investigating ways to clean wastewater more efficiently. By fostering the growth and activity of anammox, a type of bacteria that uses 60 percent less oxygen to remove nitrogen pollution, researchers have been able to lower energy and other costs. The structures seen here start off white but are colonized by anammox and other bacteria, which produces a reddish-orange biofilm.
The researchers are also investigating ways to extract the organic carbon from waste to produce biodiesel and bioplastics, and phosphorous for use in irrigation.