New invention could help reduce fatbergs and unclog sewers in Australia

Fatbergs are the cause of around 40 per cent of Australia’s sewer blockages, but their grip could be significantly reduced thanks to a new invention.

Fatbergs are congealed masses of wet wipes, oils and waste that block the sewer system, can grow to ungodly sizes and cost taxpayers up to $100 million a year.

Now a group of engineers from Melbourne’s RMIT University have invented a way to potentially reduce blockages in sewers, using an anti-fatberg coating for concrete pipes.

The invention – a zinc-reinforced polyurethane coating – targets calcium, a key contributor to fatberg formation, in the concrete that forms our sewers.

Dr Biplob Pramanik, a civil engineer who led a trial of the coating at RMIT University, said applying it to pipes prevented the release of calcium, reducing fatbergs by 30 per cent.

“When we thought about whether we could control this problem, we thought about coating (the pipes),” he said.

“This can control calcium which plays a major role in interacting with fats to form (fatbergs) into solids and create blockages.”

The protective coating has been shown to limit calcium release by up to 80% compared to uncoated concrete, Dr. Pramanik said.

He said traditional coatings in sewers, such as magnesium hydroxide, which has been widely used for decades, could control sewer corrosion but also contribute to the buildup of grease, oil and grease.

The new coating, he said, could “work with existing pipes and new pipes and has a dual function, working for both corrosion and fatberg control.”

He said engineers participating in the trial had worked with local water utilities to control fatbergs. He now hopes that this invention can be integrated into sewer management.

“It works and the next step is to optimize it… and then we can think about implementation,” he said.

“At this point we are doing more work and understanding the science and how it can be improved.”

In Geelong, western Victoria, workers will next week begin clearing a fatberg in the sewers 30 meters underground – a project Barwon Water says will be part of around $600,000 a year spent on blockages reactive sewers.

“Items such as wet wipes, tissues, sanitary items, paper towels and waste can form together, causing blockages which can lead to sewage spills,” said David Snadden of Barwon Water.

“These blockages and spills can impact our natural and built environments, as well as being costly and time-consuming to repair.”