Anaerobic Digestion

Anaerobic Digestion

Anaerobic digestion is the process by which organic matter such as animal or food waste is broken down to produce biogas and biofertiliser in an oxygen-free tank called an anaerobic digester. (Anaerobic means ‘in the absence of oxygen’).

A typical anaerobic digester is a sealed vessel, or series of vessels, in which bacteria act without oxygen.  The organic material needs to be fully mixed and warmed, usually to blood temperature.


Anaerobic digestion is recognised by the government bodies and environmental organisations as one of the best methods for food waste recycling and dealing with farm waste and sewage sludge.


Biogas is the name given to the mixture of gases formed during the anaerobic digestion process, mainly consisting of methane (c70%) and carbon dioxide (c30%). Biogas can be burned to produce both heat and electricity, while methane can be used as vehicle fuel or injected into the gas grid.


What’s left from the process is a nutrient rich biofertiliser which is pasteurised to kill any pathogens, then stored in large covered tanks ready to be applied on farmland in place of fossil fuel derived fertilisers.


Every tonne of food waste recycled by anaerobic digestion as an alternative to landfill prevents between 0.5 and 1.0 tonne of CO2 entering the atmosphere, one of the many benefits of anaerobic digestion.

Recommended pumps and brands for the anaerobic digestion industry



(Shown left) Heavy duty solids handling suitable for pumping slurries and sludges. They also have a large combination of wearing parts.




AL Series – suitable for cleaner water applications


AW Series – small solids handling, ideal for yard drainage and run-off water.


Peristaltic Pumps


Excellent for sludges with considerable increased wear life over other pumps such as lobe pumps. Atlantic Pumps are the exclusive UK distributor for Danish-based peristaltic pumps manufacturer LSM pumps. For further information on LSM, please visit our dedicated brand page here.