From Biomass to Biogas
How is biogas produced?
Biogas plants predominantly process energy-rich vegetation, such as grass silage, maize and sugar beet, as well as solid manure and slurry. In addition, organic residues, such as lawn cuttings, food leftovers or by-products from the food processing industry can be fermented.
Biomass is broken down by special bacteria under the exclusion of oxygen. In this process, approximately two thirds of the total amount of gas produced by the bacteria is methane; carbon dioxide, nitrogen and a small number of other gases are also produced.
The methane can be used as fuel in CHP modules, where it generates power and heat. If the biogas is scrubbed, it can also be fed into the gas mains to supply decentralised CHP modules with biogas. One cubic meter of methane contains a calorific value of 10 kWh. The fermented plant residues can be reused in agriculture as a high grade fertiliser.
Fermenting materials (such as, for example, sustainable raw materials, slurry, solid manure and biowaste) -- Silos for storage – Digester -- Residual digestion store / Discharge as fertiliser -- Gas treatment -- Combined heat and power units (CHP).