Anaerobic Digestion of Food Waste

ReFood UK is the UK's leading operator of AD facilities custom designed and built to handle food wastes diverted from landfill.

There are currently 11 ReFood plants operating in Europe - 5 in Germany, 4 in France and 3 in the UK.

The ReFood AD plants operate as integrated recycling units, processing a variety of food wastes to produce renewable electricity, heat and ReGrow, a nutrient-rich fertiliser for local farms. The plants also recycle the food waste packaging.  The plants provide an environmentally-sustainable solution for all waste producers looking for a safe method of diverting food waste from landfill.

ReFood's first UK AD plant opened in September 2011 in Doncaster, South Yorkshire and was expanded in 2014. The plant processes approximately 160,000 tonnes of food waste per annum, collected from local shops, restaurants and cafes as well as residues from SARIA Group's petfood production plant.

The Doncaster ReFood plant generates just under 5MWh of renewable energy, which is used to power the Doncaster site and supply the national grid; the plant also features a high-efficiency heat recovery system which supplies heat and hot water to the adjacent Oils and Fats refinery.

The second ReFood plant in the UK at Widnes opened in June 2014; a third site at Dagenham in east London opened in July 2017.   Whereas Doncaster uses the biogas produced by AD to fuel the CHP engines, the Widnes and Dagenham plants refines the biogas to produce bio-methane which is then exported to the National gas grid to replace fossil fuel.


What is anaerobic digestion?

Anaerobic digestion (AD) is the term applied to the process of the biological breakdown of organic material in the absence of oxygen.

During the process organic matter such as food waste is broken down biologically and this generates large amounts of biogas - a mixture of methane and carbon dioxide.

The process is similar to that which takes place during composting, however it is done in the absence of oxygen and the methane generated is captured and utilised as a biogas rather than being lost to the atmosphere.

The biogas generated by ReFood's Doncaster AD plant is used as a fuel for the 5MW combined heat & power engines to generate heat for the processing site and for the generation of renewable electricity.

The biogas produced by the Widnes & Dagenham plants is refined and then exported to the national gas network. 

By using biogas from the AD process as a fuel the ReFood plant is displacing the use of fossil fuels; this in turn reduces the amount of carbon dioxide released into the atmosphere.

As well as producing biogas for the generation of 'green' energy, the AD plants also produce ReGrowa nutrient-rich liquid fertiliser for use by local arable farms.

Read more about ReFood's AD services»