Anaerobic Digestion

The remaining small fraction of waste sorted and processed from the Mechanical Biological Treatment (MBT) process is further treated using a biological process called Anaerobic Digestion (AD).

Here, material is placed in sealed vessels and heated to a temperature of around 57ºC for a period of around 20 days to break down the matter. This produces:
• Biogas − a methane-rich gas which will be used to produce green electricity (around 2MW of power) – half of which will be used to run the site and the rest will be fed into the national grid; and
• Refuse Derived Fuel (RDF) − an energy source for use in thermal power generation at a separate site.

Click here to find out more about MBT and AD.