New Sludge Dryers Enhance Sustainability of Water Treatment Chain
Aquafin has started the construction of two CO₂-neutral sludge dryers in Beringen and Roeselare. The residual heat from Biostoom Beringen and the intermunicipal organization Mirom will be used to dry the sludge from wastewater treatment plants (WWTPs).
Together with Aquafin, Stadsbader, and Huber, Sweco has been responsible for the design and preparation of the environmental permit for both sludge dryers. We also contributed to the HAZOP (Hazard and Operability Analysis) to ensure maximum integration of safety aspects into the concept. Currently, we are working on the architectural design, structural stability, and building systems.
This project is a crucial step in Aquafin’s ambition to make wastewater sludge processing more efficient and sustainable. The two new facilities are expected to be operational by 2026, replacing three outdated sludge dryers in Deurne, Leuven, and Houthalen. With an investment value of over €110 million, this project plays a key role in achieving Aquafin’s goal of eliminating fossil fuels from the sludge treatment process.
Dried Sludge Valorized as Fuel
With the construction of new sludge dryers, Aquafin is taking a significant step toward a CO₂-neutral future. These innovative facilities combine advanced technology, sustainable energy sources, and residual heat, setting a new standard for sludge treatment and contributing to the circular economy. The dried sludge does not end up as waste but is valorized as fuel in a planned mono-processing facility. Here, it will be used to generate high-pressure steam for industrial processes, making sludge treatment both more sustainable and circular. The locations in Beringen and Roeselare have been strategically chosen to ensure efficient sludge transport and minimize transport distances.

Design & Build Follows Successful Permit Process
The project was launched through a design-and-build procedure, with the Stadsbader-Deckx-Sweco-Huber team selected as the best bidder. After a complex permitting process, the permits for the Beringen and Roeselare sites were granted in June and August 2024, respectively. During the permitting phase, Sweco was responsible for the architectural, structural, and process design. In the execution phase, our teams are handling the detailed engineering of architecture, structural stability, and building systems, while also coordinating with Deckx and Huber, who are carrying out the detailed process engineering. At both sites, construction has now started with the installation of pile foundations and retaining walls for the deeply excavated sludge bunker.
