The Brabantse Delta Water Board is renovating the fermentation tank at the Dongemond water treatment plant. This tank ferments wastewater sludge into biogas. With new mixers and a fresh inner layer, the water board aims to produce more gas using less electricity. This will help lower energy bills and increase its own clean energy production.
Every resident pays a sewage tax. The more efficiently the treatment plant operates, the better the costs can be managed. Additional biogas means more on-site electricity and heat. This makes the plant less dependent on grid purchases and less sensitive to price fluctuations. It's also a step in the broader direction of water boards to operate their plants as energy factories.
The concrete tank will be cleaned and recoated. The old agitator will be replaced by two vertical mixers that require less electricity. This allows for more consistent fermentation and produces more biogas from the same sludge. The tank will be gas-freed and ventilated beforehand for safety reasons, after which the renovation can begin.
Impact on energy and climate
Biogas from sewage sludge replaces natural gas or purchased electricity at the treatment plant. It reduces emissions and contributes to the water boards' goal of climate neutrality. The approach demonstrates how waste can be transformed into a raw material and how local infrastructure can contribute to the energy transition without taking up new space.
The Netherlands has dozens of wastewater treatment plants using anaerobic digestion. Many facilities are due for major maintenance. By choosing technology that requires less energy and produces more biogas during renovations, you win twice. Dongemond is not an isolated case; it fits into a trend of smarter use of existing assets.
Source: Brabantsedelta.nl
Photo: Video still of “Dongemond WWTP timelapse scaffolding construction fermentation tank”
