New wastewater tech tackles fatbergs at the source

New wastewater tech tackles fatbergs at the source

A new wastewater treatment system developed by RMIT University researchers could help prevent fatbergs – solid masses of fat, oil and grease (FOG) that clog sewers and cost water utilities globally billions to remove each year.

These congealed blockages, formed when FOG binds with wet wipes and other debris, reduce sewer capacity, trigger overflows and pose public health risks.

But a team from RMIT’s Effective Technologies and Tools (WETT) Research Centre has developed a solution that combines a redesigned grease interceptor with a smart chemical treatment – more than doubling fat removal rates in commercial kitchen wastewater.

“This is a major step forward in preventing FOG from entering our sewers from the biggest contributors: commercial food establishments,” said senior lead researcher and WETT Director Dr Biplob Pramanik.

“Traditional grease traps aren’t designed to catch the finer particles and emulsified fats in modern kitchen wastewater. Our system targets all fat types, even hard-to-remove emulsified fats that slip through conventional traps.”

Two researchers, a man and a woman, smile at the camera in a lab. Both wear lab coats, safety glasses and gloves. The woman holds a large beaker filled with clear water. They are Dr Biplob Pramanik and Dr Nilufa Sultana of RMIT University.RMIT researchers Dr Biplob Pramanik and Dr Nilufa Sultana are part of the team behind new technology to prevent fatbergs in our sewers. Their system removes up to 98% of fats, oils and grease from commercial kitchen wastewater. Credit: Will Wright, RMIT University

The new design features a series of physical barriers, or baffles, inside a grease interceptor to slow wastewater flow and separate larger fat particles. A small dose of alum, a common water treatment chemical, is then added to clump smaller, suspended fats for easy removal.

Lead author Dr Nilufa Sultana said the system worked effectively even in real-world conditions with high temperatures and detergent use.

“While traditional interceptors only remove around 40% of fats, our system achieved up to 98% – even when tested with actual kitchen wastewater,” she said.

The researchers say the technology can be scaled for different kitchen sizes and retrofitted to existing grease management systems, offering a cost-effective way to protect sewer infrastructure and reduce maintenance costs.

Two engineers in lab coats and safety glasses stand beside a transparent grease interceptor system. The woman, wearing a hijab and blue gloves, explains the setup. The man watches attentively. They are conducting research on wastewater treatment technology at RMIT University.Dr Nilufa Sultana and Dr Biplob Pramanik next to their anti-fatberg innovation in their lab at RMIT University. Credit: Will Wright, RMIT University

Emeritus Professor Felicity Roddick said the implications went beyond infrastructure.

“Fat, oil and grease blockages can lead to sewage spills in our streets and waterways,” she said. “This research shows we can stop the problem at its source, with a simple upgrade to the systems food businesses already use.”

The RMIT team is developing a suite of integrated technologies to tackle fatbergs across the wastewater system. 

Two engineers in lab coats, safety glasses and blue gloves examine a clear container of treated wastewater. Dr Biplob Pramanik is pointing at the sample while Dr Nilufa Sultana holds it up for inspection. The photo is taken in a lab at RMIT University.Senior researcher Dr Biplob Pramanik and lead author Dr Nilufa Sultana examine treated kitchen wastewater. Their new grease interceptor design, developed at RMIT, dramatically improves fat removal and is already showing strong results in real-world conditions. Credit: Will Wright, RMIT University

Led by Pramanik, the team is collaborating with South East Water, Intelligent Water Networks, Water Research Australia, Barwon Region Water Corporation, Queensland Urban Utilities and the water technology company ACO on an ARC Linkage Project.

This project aims to optimise fluid dynamics within the grease interceptor to enhance the removal of fat, oil and grease without the need for chemical treatment, aligning with current industry practice.

A woman with short white hair stands smiling in a lab, wearing safety glasses, a lab coat and a colourful scarf. She is Emeritus Professor Felicity Roddick, visiting the RMIT wastewater treatment lab working on fatberg prevention.Emeritus Professor Felicity Roddick visits the RMIT lab where new research is helping tackle the fatberg crisis at its source. Credit: Biplob Pramanik, RMIT University

The research article, ‘Performance optimization for the removal of fat, oil, and grease from food service establishment wastewater using a novel grease interceptor’, is published in ACS ES&T Water (DOI: 10.1021/acsestwater.5c00513).

To discuss collaboration, contact research.partnerships@rmt.edu.au


Story: Will Wright

21 August 2025

Share

Return to RMIT News
21 August 2025

Share

  • STEM
  • Industry
  • Society
  • Sustainability
  • Research
  • Engineering
  • Environment
  • Science and technology
Engage

Related News

news-eureka-prize-carbon-conversion-1220px.jpg

RMIT carbon conversion technology wins Eureka Prize

A breakthrough RMIT technology that captures and converts carbon dioxide into valuable products in a single process has won one of Australia's most prestigious science awards.

Floating_titanium_thumbnail.jpg

Engineers create a world-first in floating titanium

RMIT engineers have created a strong and lightweight titanium material that floats in water, even after severe damage, revealing a promising new material for marine infrastructure.

floating_wetland_thumbnail.jpeg

Floating wetlands slash wastewater greenhouse gas emissions: study

A world-first trial of floating wetland pods in wastewater lagoons shows they cut greenhouse gas emissions by more than a quarter, highlighting their potential as a nature-based solution for decarbonising the water sector.

Alec Cameron at the AFR Higher Education Summit 2026

Greater effort required to meet higher education participation targets

The higher education sector should urgently drive new and innovative learning models to meet the federal government’s tertiary participation targets, according to RMIT Vice-Chancellor and President Professor Alec Cameron.

Show more
aboriginal flag float-starttorres strait flag float-start

Acknowledgement of Country

RMIT University acknowledges the people of the Woi wurrung and Boon wurrung language groups of the eastern Kulin Nation on whose unceded lands we conduct the business of the University. RMIT University respectfully acknowledges their Ancestors and Elders, past and present. RMIT also acknowledges the Traditional Custodians and their Ancestors of the lands and waters across Australia where we conduct our business - Artwork 'Sentient' by Hollie Johnson, Gunaikurnai and Monero Ngarigo.

More information