Mechanical Biological Treatment

The Mechanical Biological Treatment facility takes all of Cambridgeshire's residual (black bag) waste – that’s the waste which is left over after you have separated your food, garden and recycling items.

The MBT includes different technologies to sort this waste and increase the amount which is recycled.

We know some recyclable items such as cans and paper can accidentally be thrown away in the black sacks, so the use of this technology makes sure we can find and recycle them.

Bags are split open and waste goes through a trommel screen – this is like a giant sieve which sorts waste by its size.

Other technologies – including magnets and vibrating plates – can then extract items such as cans, metals, glass and stones, while targeted air jets can sort different types of plastics by blowing them into the right group.

Any rubbish left is then taken by conveyor belts to the MBT’s composting hall, where giant mechanical turning wheels keep turning it over 24 hours a day, seven days a week.

After six to eight weeks the organic material has been significantly reduced in weight. Because this is mixed waste, the material produced cannot be used by farmers or the public so it does go to landfill – however, the reduced weight means landfill costs are much lower.