Australian team uses electricity to clean up industrial wastewater

Technology developed by a team of researchers at the University of Sydney could ultimately make it easier to clean up contaminated industrial wastewater streams.

industrial wastewater
Safely managed wastewater is thought to be an affordable and sustainable source of water, energy, nutrients and other recoverable materials

The group’s electrochemical oxidation process involves treating wastewater with electricity using specialised electrodes.

These electrodes discharge electricity, then drive oxidation reactions near the electrode surfaces, transforming the organic contaminants into harmless gasses, ions or minerals.

A study published in the journal Algal Research describes how the technology was trialled on a sample of wastewater containing carbon, nitrogen and phosphorus that was generated in a pilot biofuel production plant.

“We have employed an incredibly powerful process that eliminates even the most persistent non-biodegradable pollutants, such as pharmaceuticals and pesticides, as well as various classes of organic compounds that can be found in many industrial effluents,” explained researcher Julia Ciarlini Jungers Soares.

Industrial wastewater
Water before and after electrochemical treatment. Image: Julia Ciarlini Jungers Soares, University of Sydney

The process – which is claimed to be relatively simple – doesn’t require the addition of chemicals or severe operational conditions, and does not produce additional waste streams, added Soares.

The group claims that the method could be readily applied to a wide range of industries that must comply with strict regulations for industrial wastewater disposal, such as pulp and paper processing, wineries, as well as pharmaceutical production facilities.

“Worldwide, researchers are investigating methods for the development of biofuels from algae. Developing alternatives for the treatment and reuse of this industrial effluent is a hot research topic and can bring opportunities for energy and resource recovery within a circular bio-economy framework,” said Soares.

The team now plans to carry out research focused on specific contaminants to better understand the chemical transformations that take place during electrochemical oxidation and to explore the challenges of scaling up the process.