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Anaerobic Digestion

​Anaerobic digestion is a sequence of processes by which microorganisms break down biodegradable material in the absence of oxygen.[1] The process is used for industrial or domestic purposes to manage waste or to produce fuels. Much of the fermentation used industrially to produce food and drink products, as well as home fermentation, uses anaerobic digestion.

Anaerobic digestion occurs naturally in some soils and in lake and oceanic basin sediments, where it is usually referred to as "anaerobic activity".[2][3] This is the source of marsh gas methane as discovered by Alessandro Volta in 1776.[4][5]

The digestion process begins with bacterial hydrolysis of the input materials. Insoluble organic polymers, such as carbohydrates, are broken down to soluble derivatives that become available for other bacteria. Acidogenic bacteria then convert the sugars and amino acids into carbon dioxide, hydrogen, ammonia, and organic acids. In acetogenesis, bacteria convert these resulting organic acids into acetic acid, along with additional ammonia, hydrogen, and carbon dioxide amongst other compounds. Finally, methanogens convert these products to methane and carbon dioxide.[6] The methanogenic archaea populations play an indispensable role in anaerobic wastewater treatments.[7]

Anaerobic digestion is used as part of the process to treat biodegradable waste and sewage sludge. As part of an integrated waste management system, anaerobic digestion reduces the emission of landfill gas into the atmosphere. Anaerobic digesters can also be fed with purpose-grown energy crops, such as maize.[8]

Anaerobic digestion is widely used as a source of renewable energy. The process produces a biogas, consisting of methane, carbon dioxide, and traces of other 'contaminant' gases.[1] This biogas can be used directly as fuel, in combined heat and power gas engines[9] or upgraded to natural gas-quality biomethane. The nutrient-rich digestate also produced can be used as fertilizer.

With the re-use of waste as a resource and new technological approaches that have lowered capital costs, anaerobic digestion has in recent years received increased attention among governments in a number of countries, among these the United Kingdom (2011),[10] Germany,[citation needed] Denmark (2011),[11] and the United States.[12]

​Wellingborough (/ˈwɛlɪŋbərə/ WEL-ing-bər-ə) is a large market town in the Wellingborough district of Northamptonshire, England, 11 miles (18 km) from Northampton on the north side of the River Nene.[3][4]

Originally named "Wendelingburgh" (the stronghold of Wændel's people),[5] the Anglo-Saxon settlement is mentioned in the Domesday Book as "Wendelburie". The town was granted a royal market charter in 1201 by King John.[6]

At the 2011 census, the town had a population of 49,128.[1] The Borough Council of Wellingborough has its offices in the town centre.[7] The town is twinned with Niort in France, and with Wittlich in Germany.

The town is predicted to grow by 30 per cent under the Milton Keynes South Midlands (MKSM) study, and the government has identified Wellingborough as one of several towns in Northamptonshire where growth in jobs and housing will be directed.[8] The area will see an addition of around 10,000 homes by 2031, mainly to the east of the town.[9] Wellingborough, along with Corby and Kettering together comprise the core of the North Northamptonshire growth area, coordinated by the North Northamptonshire Joint Planning and Delivery.[10] The town also has a growing commuter population as it is on the Midland Main Line railway, operated by East Midlands Railway, with trains to London St Pancras International taking under an hour, and an interchange with Eurostar services.[11]

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