Fatbergs remain one of the most persistent and costly problems in urban wastewater systems. They form when fats, oils, and grease (FOG) bind with wipes, sanitary products, and other debris, reducing sewer capacity, triggering overflows, and creating serious public health hazards. Utilities around the world spend billions each year removing them.
This week, Water Treatment 411 dives into a new solution from RMIT University that aims to stop the problem at its source.
A New Take on Grease Interceptors
Traditional grease traps remove only about 40% of fats, leaving emulsified and finer particles free to pass through. A research team at RMIT University’s WETT Research Centre came up with a solution that introduces physical baffles to slow wastewater, separating out larger particles more effectively. It then applies a small dose of alum to coagulate suspended and emulsified fats, which are otherwise the most difficult to capture.
When tested in real-world conditions, along with high temperatures, strong detergent use, and genuine commercial kitchen effluent, the system removed up to 98% of fats. That’s more than double the efficiency of current approaches.
The design is scalable for kitchen sizes ranging from small restaurants to large food processing facilities. It can also be retrofitted to existing grease management systems, a factor that significantly lowers barriers to adoption.
Cost, Compliance, and Public Health Benefits
For utilities, the implications go beyond saving on sewer maintenance. Sewer blockages create overflow events that directly increase regulatory exposure and public dissatisfaction. Preventing FOG at the source reduces spill risks and associated cleanup costs.
For food service operators, the system offers a compliance advantage. Many municipalities are tightening FOG discharge standards, and technologies like this could help businesses stay ahead of enforcement while minimizing maintenance of their own plumbing.
For public health, reducing sewage overflows lowers the likelihood of untreated wastewater reaching streets, rivers, and coastal waters.
Integration and Next Steps
The RMIT team is not treating this as a one-off invention. The technology is part of a broader suite being developed with partners including South East Water, Barwon Region Water Corporation, Queensland Urban Utilities, and ACO. Their next phase focuses on optimizing interceptor fluid dynamics to maximize FOG removal without relying on chemical dosing.
That direction matters for long-term sustainability. While alum is cost-effective and widely used in treatment, minimizing reliance on coagulants aligns with utility goals to reduce chemical inputs where possible. If fluid dynamics optimization proves successful, future interceptors could be even more efficient, chemical-free, and maintenance-light.
What This Means for You
This development highlights two key takeaways. First, prevention at the source remains one of the most cost-effective strategies for infrastructure protection. Fatbergs are expensive to remove, but preventing them is comparatively cheap. Second, partnerships between researchers, utilities, and technology providers are accelerating solutions that are immediately practical.
Stay tuned to Water Treatment 411, and keep an eye out on the rollout of these technologies. Widespread adoption in the food service sector could significantly reduce FOG load on wastewater systems, freeing up resources for utilities to focus on other pressing challenges like emerging contaminants or climate-driven system resilience.
SOURCES: ACS ES&T Water, Smart Water Magazine
