Centralisation of sludge fermentation at Ede WWTP

At the wastewater treatment plant (WWTP) in Ede, Vallei en Veluwe Water Board treats wastewater from the surrounding region. To organise sludge treatment more efficiently and sustainably, the water authority is decommissioning several small-scale fermentation plants in the region and centralising sludge treatment at a single location: WWTP Ede. A new central sludge fermentation facility has therefore been designed, generating sustainable gas from sewage sludge and contributing to the water authority’s energy ambitions. The design was developed by a building team comprising CLC Water and Iv. Iv was responsible for the civil and mechanical engineering aspects.

Working in a building team involving multiple parties and a complex division of responsibilities required precise coordination. Weekly on-site meetings, rather than digital meetings, enabled direct communication and engagement, but also demanded flexibility and tight coordination between the various disciplines. Additionally, the project for the centralisation of sludge fermentation at Ede WWTP included a challenging schedule, but thanks to effective collaboration, the design was delivered on time as agreed.

Sustainability also played a major role. Extensive research was conducted into the feasibility of using geopolymer concrete – a sustainable alternative to traditional cement concrete. The outcome was positive, making CSV Ede the first sludge fermentation facility in the Netherlands to be constructed using geopolymer concrete. This choice will significantly reduce the project’s CO₂ footprint.

The design for the centralisation of sludge fermentation at WWTP Ede supports the water authority’s policy objectives: a more sustainable, efficient, and future-proof treatment process. By centralising sludge processing, the installation optimises energy usage. The installation converts sewage sludge into green gas, which is then upgraded to natural gas quality.