Blue bin - 'dry' recycling
When the blue bin lorries are full, they empty their load at a 'waste transfer station' in Waterbeach. From here the recycling is loaded into large articulated lorries and then taken to a sorting plant, called a 'Materials Recycling Facility' (MRF) in Peterborough.
Once at the sorting plant a variety of magnets, eddy currents (reverse magnets), size-sorting equipment and conveyor belts separate the different materials. The materials are then baled and sold to processors who melt, pulp or crush them to make new products.
Paper
Paper is sorted into different grades and sent on to mills to be pulped and made into a variety of different paper products.
Glass
Some glass that has not broken before it gets to the MRF can be melted and used to make new bottles. The rest of the glass is crushed and used as aggregate in construction, or as filtrates in filter beds.
Cans
Cans are separated into aluminium and steel at the MRF. Then they are melted by processors to form ingots to sell to manufacturers who can make anything from bikes and aeroplanes to new cans.
Plastic bottles
Plastic bottles go through a further sorting phase to separate the different polymer types. They are then shredded and cleaned by a machine that rubs the flakes together. They are usually then melted into tiny pellets that are sold to manufacturers to make new plastic bottles, garden furniture and even fleece jackets.
Cartons
Drinks cartons (eg Tetra Pak cartons) are pulped and the paper parts are used to make plasterboard lining, envelopes, paper bags and other low-grade paper products.
Green bin - food, cardboard and garden waste
The waste from your green bin is taken to Donarbon near Waterbeach - here it goes through an intensive 'in-vessel' composting process.
The resulting soil conditioner is sold for local agriculture, and is also available to householders to collect free of charge from the site. Please call 01223 861010 for details.
Black bin - non-recyclable rubbish
Black bin rubbish is taken to Donarbon where it is passed through the Mechanical Biological Treatment plant (MBT). The MBT mechanically removes some items from the waste and then treats the rest in a huge composting hall. This breaks the waste down as much as possible, helping to reduce methane and carbon dioxide emissions it might release if it were simply landfilled.
The resulting compost-like output might be used for growing non-food crops like turf, as fuel in an energy-from-waste plant, or for quarry restoration. The material needs to be tested before the best application is decided on.
How the recycling rate is worked out
All of the rubbish that you recycle or dispose of is weighed. This is done by weighing the collection vehicles on a weighbridge before and after they empty a load.
The recycling rate is worked out by subtracting the total weight of materials diverted from landfill (recycled or composted) from the total amount of materials collected.
Cambridge's recycling rate for 2007/08 was 42%.
The UK’s national recycling rate is about 37%.
