Anaerobic Digestion: All You Need To Know
Anaerobic Digestion has become an increasingly popular way for businesses to deal with their waste, and reduce their carbon footprint. But what exactly is it?
In the 2007 Waste Strategy for England, businesses were urged to consider AD as a way of helping the UK meet European waste and recycling targets. DEFRA (Department for Environment, Food and Rural Affairs) published a report which claimed that, at its full potential, AD could potentially produce enough electricity to power 2 million homes.
In 2015, there were over 200 operational AD plants in the United Kingdom, which generated enough energy to power over 500,000 homes.
Here is all you need to know about this innovative process, which turns organic waste into sustainable energy.
What Is Anaerobic Digestion?
Anaerobic Digestion is a treatment applied to organic waste. It is a series of biological processes in which microorganisms break down food waste, manure, etc in the absence of oxygen. The process results in the production of Biogas, a methane-rich gas, which once it has been cleaned is used either in a power generation unit or a chp unit within the site.
How Does AD Work?
Anaerobic Digestion takes place inside equipment known as an Anaerobic Digester. This is a large, sealed, oxygen-free tank. The waste and organic material (biomass) is heated to around 55°C, which causes it to react with naturally occurring micro-organisms and bacteria to produce biogas and a compost-like product. The digestion process takes three to four weeks, after which the gas is extracted. The Biogas is taken to a Combined Heat and Power (CHP) unit, where it is used to generate renewable energy. The digestive material is often used as fertiliser.
What are the Benefits of Anaerobic Digestion?
Waste Management: AD is an innovative way of dealing with organic waste and diverting it from landfill. The breakdown of animal slurry, food waste etc leads to the production of methane, which is 25 more times more powerful than CO2 as a greenhouse gas. The AD sector could reduce the UK’s total greenhouse gas emissions by over 2%.
Nutrient Management: Organic waste (including food, manure and waste water) contains valuable nutrients. Through AD the material retains its nutrients, while pathogenic organics and foul odours are eradicated. The nutrient-rich residues which remain at the end of the AD process are; a nutrient rich liquid which can be sprayed onto or injected into the land and a nutrient rich compost-like soil improver which can be spread onto soil as an alternative to chemical fertiliser.
Renewable Energy: AD produces a methane-rich biogas,which, once cleaned, can be put back into the mains gas supply for other users as well as transported to other locations for storage and use on remote sites for generating either electric and or heat and power.
Anaerobic Digestion in Northern Ireland
ISL Waste Management sends tonnes of food and organic waste, collected from our industrial and commercial clients, to Anaerobic Digestion plants across NI. In the UK, around 40% of food waste ends up in landfill each year. We are committed to reducing this figure and first work with clients to help them reduce their waste, through increased efficiencies and streamlined processes. We then strive to deal with essential waste in the most environmentally sound way possible.
Since August 2009 ISL have successfully diverted over 10,000 tonnes of food waste to both AD plants and composting facilities. This figure is increasing this year on year.
Get in touch with ISL Waste Management, Belfast today and we’ll help turn your food waste into a valuable resource.