14 Facts About Anaerobic digestion

Anaerobic digestion is a sequence of processes by which microorganisms break down biodegradable material in the absence of oxygen.

Anaerobic digestion occurs naturally in some soils and in lake and oceanic basin sediments, where it is usually referred to as "anaerobic activity".

Anaerobic digestion is used as part of the process to treat biodegradable waste and sewage sludge.

Four key stages of anaerobic digestion involve hydrolysis, acidogenesis, acetogenesis and methanogenesis.

Anaerobic digestion can be performed as a batch process or a continuous process.

Examples of this form of anaerobic digestion include continuous stirred-tank reactors, upflow anaerobic sludge blankets, expanded granular sludge beds, and internal circulation reactors.

In contrast, while thermophilic Anaerobic digestion systems are considered less stable, their energy input is higher, with more biogas being removed from the organic matter in an equal amount of time.

Length of time required for anaerobic digestion depends on the chemical complexity of the material.

Anaerobic digestion microorganisms are generally unable to break down lignin, the recalcitrant aromatic component of biomass.

Anaerobic digestion digesters were originally designed for operation using sewage sludge and manures.

Anaerobic digestion is particularly suited to organic material, and is commonly used for industrial effluent, wastewater and sewage sludge treatment.

In developing countries, simple home and farm-based anaerobic digestion systems offer the potential for low-cost energy for cooking and lighting.

In countries where the driver for the use of anaerobic digestion are renewable electricity subsidies, this route of treatment is less likely, as energy is required in this processing stage and reduces the overall levels available to sell.

Anaerobic digestion'story of anaerobic digestion is a long one, beginning as early as tenth century BCE in Assyria where biogas was used to heat bath water.