Anaerobic Digestion is the degradation of organic wastes in the absence of oxygen and has been used for many years for the treatment of agricultural and sewage sludges.
Anaerobic digestion is carried out in an oxygen-free environment (known as anaerobic conditions) to allow the presence of bacteria adjusted to these conditions which then multiply and grow, and by so doing achieve the process aims of: sanitisation of the feed material and of any liquid discharged; and a net positive surplus generation of energy as a biofuel to allow power production from methane gas (biogas) produced by the organisms.
The process has the advantage of producing gas for energy recovery in addition to a usable end product. The Publicly Available Specification (called PAS110) for digestate derived from anaerobic digestion of source segregated biodegradable materials creates an industry specification against which producers can verify that the digested materials are of consistent quality and fit for purpose.
