HoSt has constructed a biogas plant in Waalwijk, the Netherlands, with the purpose of generating biomethane (green gas) from various waste streams like roadside grass, vegetable waste, flotation sludge’s and unpacked supermarket waste. Due to the combination of different innovative techniques, it is one of the most advanced biogas units in the world.

The solid feeding system is capable of handling difficult fuels. The installation is provided with a size reduction step to make it possible to use high amounts of grass.

In this project, a biogas upgrading unit is placed to upgrade biogas to the quality of natural gas. The capacity of the plant is 850 m³/h biogas that will be upgraded to 500 m³/h biomethane. The biogas upgrading has an integrated heat recovery system, so that no gas is needed for the digester. The biomethane is injected into the national gas grid. The upgrading kit including compressor, membranes, control panel, heat recovery, odorisation and biogas analysis is placed in three containers. The three containers are located at an upgrading island besides the AD-plant.

The digestate coming out of the AD-plant will be processed to dischargeable water that will be discharged into the sewer. This is reached due to a screw press separator in combination with a decanter centrifuge and PE-injection. Deammonification is done by the DEMON® process.


Start construction October 2014
Start-up/ commissioning May 2015


Capacity 50.000 m³ / year
Input roadside grass, vegetable waste, flotation sludge’s and unpacked supermarket waste
Digester 1 * 3000 m³ (centrally mixed)
After-digester 1 * 2600 m³
Production Biomethane 500 m³/h
Liquid storage 6 * 150 m³
Solid feeding input 80 m³ with input system suitable for grass + cutting device


Capacity 850 m³/h
Methane concentration raw biogas 55 – 60%
Methane concentration product gas up to 97% (89% because of Dutch low calorific natural gas)
Efficiency > 99%


  • Solid feeding for difficult fuels
  • Biogas upgrading with integrated heat recovery
  • Digestate to clean water and solid compost

More information

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