The digestion plant of Water Board Reest en Wieden ensures that the entire sewage treatment plant, including sludge digestion, runs energy neutral. The system leads to a reduction of the cost of sludge treatment and the raw materials can be recovered.

It’s the first system in the Netherlands that digests sludge in a thermophilic digester, followed by a mesophilic digester. With this combination, a higher degradation is achieved in comparison with conventional technology for sludge digestion. During multiple tests, the increased sludge digestion is demonstrated.

HoSt is responsible for the design, construction and commissioning of the plant and also provides for process technical guidance during the warranty period of 1 year.

Learn more in this video:


Start Construction April 2012
Startup May 2013


Capacity 193,000 m³/year
Input Secondary sludge from several wastewater treatment plants
Digester(s) 1 x 4,100 m³ (thermophilic);
1 x 5,800 m³ (mesophilic)
After-digester(s) 1 x 2,000 m³
CHP(s) 1 x 600 kWe
Pre-strorage/receipt 1,100 m³ mixing tank and 2 x 2,500 m³ silos for receipt
Digestate treatment Phosphate removal in struvite reactor


  • Increased sludge digestion with combination of thermophilic / mesophilic digestion
  • Struvite reactor for phosphate removal and struvite recovery
  • Optimization by pre-thickening sludge

More information

Do you want to receive more information about our biogas plants, want to learn more about our sludge digestion technology or do you want to know what HoSt can do for you? Don’t hesitate to contact us through [email protected] or call us on +31 (0)53 – 460 90 80.