Axpo Kompogas Ltd

The patented Kompogas process is based on the continuous dry fermentation of organic waste using a plug-flow digester. The fermentation process is both thermophilic and anaerobic. In this kind of dry fermentation, the temperature in the digester is maintained at 55°Celsius. The average substrate moisture is around 75% and the retention time is approximately 14 days. The Kompogas process ensures that the organic waste is degraded properly and freed of undesired spores, germs and micro-organisms.

The continuous-feed, horizontal plug-flow digester facilitates a high gas yield and offers high operating reliability thanks to the simple and efficient control systems. A low-speed agitator ensures the optimum formation of methane. The special design and arrangement of the agitator paddles also prevents sedimentation of dense media materials in the fermentation substrate.

Fermentation involves various upstream and downstream processes. Via a feed unit, the organic waste is fed into the digester for treatment. Subsequently, the substrate is automatically conveyed to the digester. A discharge pump withdraws the hard substrate. Around one-third of this substrate is pumped back for inoculation. The remaining quantity is either pushed out of the digester or mixed with green waste using the partial flow process.