Biomethane plant in Oberlauterbach

Hallertau produces nearly one third of the global hops production, which is used to flavour beer around the world. Only female flowers are used in the production of the drink. What happens to the rest of the plant? Traditionally, the plant is chopped and used as a soil conditioner. At the time of harvesting, however, there is no need to fertilise the soil; hence, the waste needs to be stored.

There is also another problem: the presence of iron wires that are used to tie the plant to the supports. Their presence creates issues for transport and for use as a soil conditioner. Without adequate pre-treatment, the plant is unusable.

Chopped hop plants are a valuable material, rich in fibre and with a high dry matter content. The biogas plant developed by Schmack follows a two-stage process and consists of three EUCO® continuous plug-flow fermenters and four COCCUS® secondary fermenters.

In the EUCO®, the substrate becomes more liquid, since the first phase of the anaerobic digestion breaks down the complex organic molecules, releasing water. This way, the secondary fermenters require lower mixing power. The EUCO® plants don’t just facilitate hydrolysis; that’s where approx. 50% of the biogas is produced. The combination of both types of fermenter produces the largest quantity of biogas.