Anaerobic mono-manure digestion for combined heat and power (CHP) production – small-scale

The data refers to small scale 100% manure installations. The manure, at the farm level, is fermented in an anaerobic digestion installation to produce biogas. The biogas is fed into a cogeneration unit to produce electricity and heat. Biogas is a blend of methane (50–75% CH₄) and carbon dioxide (25-50% CO₂) with some trace amounts of ammonia (NH₃), hydrogen sulphide (H₂S), and water.

Digestate is often separated into a thick and thin fraction. The thick fraction can then be hygienized to make it safe for use or export as a fertilizer. The hygienisation prior to export is mandatory. During hygienisation, the digestate is kept at a temperature of at least 70°C for one hour. The thin aqueous fraction can be further purified to a concentrated fraction and water.