Wastewater treatment system recovers electricity, filters water

Whether wastewater is full of “waste” is a matter of perspective.

“Why is it waste?” asked Zhen (Jason) He, the Laura and William Jens Professor in the Department of Energy, Environmental & Chemical Engineering in the McKelvey School of Engineering at Washington University.

“It’s organic materials,” He said, and those can provide energy in a number of ways. Then there is the other valuable resource in wastewater.

Water.

He’s lab has developed one system that recovers both, filtering wastewater while creating electricity. Results from bench-scale trials were published May 6, 2021, and featured as a front cover article in the journal Environmental Science: Water Research & Technology.

In addition to the paper’s first author, Fubin Liu, a PhD candidate at Washington University, He collaborated with two scientists from the Institute of Graduate Studies and Research at Alexandria University in Egypt: Mohammed Salah El-Din Hassounab and Hanan Moustafa.

He says the waste materials in wastewater are full of organic materials which, to bacteria, are food.

“Bacteria love them and can convert them into things we can use,” He said. “Biogas is the primary source of energy we can recover from wastewater; the other is bioelectricity.”

He’s research focuses on more efficiently recovering valuable resources from wastewater, both by improving existing technologies and developing novel ones.

Collaboration with Alexandria University

Proper treatment of municipal wastewater is critical to societal development and human health. The existing treatment technologies consume a large amount of energy, and the valuable resources in wastewater are not well recovered.

Supported by the U.S. – Egypt Science and Technology Joint Fund, researchers from Washington University and Alexandria University are jointly developing innovative wastewater treatment systems to enhance resource recovery and wastewater reuse. The recovered resource includes bioenergy, nitrogen, and high-quality water for reuse.

The Washington University team recently hosted Hanan Abdallah, the co-principal investigator of the Egyptian team from Alexandria University. The collaboration has generated four jointly authored papers in premier environmental journals such as Water Research, Environment International, and Chemosphere. The project has attracted other Egyptian researchers to Washington University, including a Fulbright scholar, Mostafa El-Nahas, from Cairo University, and a visiting scholar, Rehab Hamdy Mahmoud ElSayed, from National Research Centre, Egypt.