Beneficial biofilm works as a 'probiotic' to control biofouling

Monday, May 2, 2016

A team of chemical engineers at Penn State has developed a beneficial biofilm with the ability to prevent the biofouling of reverse osmosis (RO) membranes.

The biofilm allows membranes to limit their own thickness via a quorum-sensing circuit, and ultimately to reduce the occurrence of biofouling in membrane-based water treatment systems by releasing chemicals that repel undesirable bacteria.

“We realized that the accumulation of microbial films in water treatment membranes is unavoidable,” said Manish Kumar, assistant professor of chemical engineering and the principal investigator on the project. “But just like good bacteria exists in your gut to keep you healthy, we predicted that helpful bacteria in RO may be able to prevent the unchecked reproduction of harmful biofilms. Essentially, our method is a ‘probiotic-approach’ to combat biofouling.”

With the demand for access to safe and clean water escalating globally, membrane filtration technologies are quickly becoming popular ways to utilize low quality and readily abundant water sources such as seawater, brackish water and recycled wastewater.

Complications with these systems arise frequently, however, most often in the form of biofouling—a buildup of microbes and bacteria on membrane surfaces that causes clogging and leads to decreased membrane permeability and an overall increase in energy consumption.