A groundbreaking wastewater treatment system developed by researchers at RMIT University promises to tackle the global issue of fatbergs—solid masses of fat, oil, and grease (FOG) that clog sewers and cost water utilities billions annually. These blockages, which form when FOG binds with wet wipes and other debris, significantly reduce sewer capacity, trigger overflows, and pose public health risks.
The team from RMIT’s Water: Effective Technologies and Tools (WETT) Research Centre has engineered a solution that combines a redesigned grease interceptor with a smart chemical treatment, effectively 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,” stated Dr. Biplob Pramanik, senior lead researcher and WETT Director.
Revolutionary Design and Chemical Treatment
The new system features a series of physical barriers, or baffles, within a grease interceptor to slow wastewater flow and separate larger fat particles. A small dose of alum, a common water treatment chemical, is then introduced to clump smaller, suspended fats for easy removal. This approach targets all fat types, including the hard-to-remove emulsified fats that often evade conventional traps.
Dr. Nilufa Sultana, the lead author, emphasized the system’s efficacy under real-world conditions, noting, “While traditional interceptors only remove around 40% of fats, our system achieved up to 98% – even when tested with actual kitchen wastewater.”
Scalability and Industry Implications
The researchers highlight the technology’s scalability for different kitchen sizes and its potential for retrofitting existing grease management systems, offering a cost-effective solution to protect sewer infrastructure and reduce maintenance costs. Emeritus Professor Felicity Roddick noted the broader implications, stating, “Fat, oil, and grease blockages can lead to sewage spills in our streets and waterways. 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 also developing a suite of integrated technologies to combat fatbergs throughout the wastewater system. Led by Dr. Pramanik, the team collaborates 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 initiative aims to optimize fluid dynamics within the grease interceptor to enhance FOG removal without chemical treatment, aligning with current industry practices.
Research and Future Prospects
The research article, titled “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. This publication underscores the significant advancements made by the RMIT team in addressing a pervasive environmental challenge.
Looking ahead, the implications of this technology extend beyond immediate infrastructure improvements. By reducing the incidence of fatbergs, cities can mitigate the risk of environmental contamination and public health hazards associated with sewer overflows. As the technology gains traction, it could set a new standard for wastewater management in commercial kitchens worldwide.
For more information, images, and video footage of the team and their innovation in the lab, visit: RMIT University Media Resources.
