News Feature | August 26, 2014

Bacteria: The Key To Desalination?

Sara Jerome

By Sara Jerome


The federal government is funding research to investigate how bacteria could be used to improve desalination processes.

Researchers at Rice University, armed with around $1 million in National Science Foundation (NSF) grants, are working on reengineering bacteria to suit particular purposes.

The researchers "believe they can help reduce the buildup of biofilms in desalination equipment. Biofilms are thin layers of cells that stick to each other on a surface and have the ability to obstruct the flow of liquids in water purification systems," the NSF, a federal agency, reported

"Biofilm control is crucial for bacteria-based environmental remediation and for modern desalination," an abstract of the study said. 

Focusing on a species called Bacillus subtilis, the researchers want to create new, reliable behaviors in the bacteria, the NSF report said. 

Ryan Cheng, one of the researchers, explained why the idea could work.

"It has been shown experimentally that wrinkle formation in the biofilms of B. subtilis result from localized cell death," Cheng said in the report. "Since cell death is regulated by two-component and related signaling systems, the potential for controlling the morphology and mechanical properties of biofilms exists."

Research in this vein could have practical implications, according to Joshua Boltz, senior technologist at CH2M HILL, an engineering company with an influential water solutions program.

"The potential applications for sanitation engineers are both numerous and profound," he said in the report. "Using membranes as a desalination tool to separate solids from liquids has emerged as a mature technology that is widely used globally."

He added, "a key concern with using membranes is their fouling, or a reduction in filtration capacity due to orifice clogging as a result of biofilms."

The federal government also funds a Brackish Groundwater National Desalination Research facility, which began its work in 2009.

Desalination supporters have framed it as California's best path through the effects of the historic drought. But the inefficiency and expense of desalination has also created doubts. 

"Currently California is building the largest desalination plant in the Western Hemisphere in Carlsbad. At a cost of $1 billion, the plant will produce 50 million gallons a day for San Diego County by 2016," the International Business Times recently reported. "Fourteen other desalination plants are in the works. Critics say the process is too costly."

Check out Water Online's Desalination Solution Center

Image credit: "Cell Culture," Umberto Salvagnin © 2008, used under an Attribution 2.0 Generic license: