Australian researchers use electricity to clean up contaminated wastewater

Researchers from the School of Chemical and Biomolecular Engineering at the University of Sydney in Australia have used electricity for cleaning up heavily contaminated industrial wastewater streams.

Wineries, pharmaceutical manufacturers and other industries that need to comply with strict wastewater regulations are expected to benefit from these findings.

The researchers have developed an electrochemical oxidation process in order to clean up contaminated wastewater that contained a toxic cocktail of chemical pollutants.

University of Sydney researcher Julia Ciarlini Jungers Soares said: “Our study, published in Algal Research, involved industrial wastewater that had been heavily contaminated with a cocktail of organic and inorganic species during a biofuel production process.”

A pilot plant designed by the team was used to generate the wastewater, which contained carbon, nitrogen and phosphorus. The plant has been designed to produce biofuels using naturally abundant microalgae.

As part of the process, the contaminated wastewater was treated with electricity using specialised electrodes.

During this process, they discharged electricity, drove oxidation reactions later near the electrode surfaces and transformed the organic contaminants into harmless gasses, ions or minerals.

The process does not require the addition of chemicals or severe operation conditions. It also does not produce additional waste streams.

Soares further added: “Wastewater is a significant issue for our environment, as well as for many industries who use substantial volumes of water in their processes, such as in reactions, transport, and washing and cooling. Finding suitable solutions for reuse or disposal is often very challenging and costly.

“The electrochemical method that we used can be readily applied to industries that must comply with strict regulations for wastewater disposal, such as pulp and paper processing, wineries, as well as pharmaceutical production facilities.”

Going forward, the team plans to conduct research focused on specific contaminants to better understand the chemical transformations that would occur during electrochemical oxidation.