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What happens to your food waste recycling

Your food waste is recycled by Bio Collectors in Mitcham. Here it is anaerobically digested (decomposed in the absence of oxygen), in a controlled system.

The process uses naturally occurring micro-organisms to break down the organic matter into a digestate, a compost-like product used as a soil conditioner and fertiliser on farmland, whilst also producing biogas (mainly methane).

The biogas is fed into the National Gas Grid, so the energy produced from recycling food is provided straight to homes and businesses, helping to reduce the UK's reliance on less sustainable energy sources such as natural gas (a fossil fuel).

Food waste recycling process

  1. Residents separate their food waste for recycling and present their food waste boxes for collection each week.
  2. Our waste collection contactor empties the food waste boxes and delivers the contents to the West London Waste Authority’s depot in Transport Avenue in Brentford.
  3. Bio Collectors collect your food from the depot  and take it to their  anaerobic digestion (AD) plant in Mitcham to begin the recycling process.
  4. Bio Collectors do their best to mechanically remove  any packaging, plastic or other materials  contaminating the food waste. It is then broken down into small particles.
  5. The resulting food waste is pumped through a series of temperature-controlled tanks and  is  carefully monitored to ensure the bacteria have  the optimal conditions to digest the food effectively.
  6. After 72 hours, the waste will be producing bio-gas (mainly methane, which is filtered, screened for purity and then fed into the National Gas Grid, helping to supply homes and businesses with clean, renewable energy.
  7. Once the bio-gas has been released the food waste turns into a 'digestate', a compost-like product meeting the PAS110 standard which is used as a soil conditioner and fertiliser on farmland. This helps farmers produce more food and revitalise the land without the need for industrial chemicals.

Updated: 04 March 2021