Outing to Cupids Green April 2013

On the 23 April, the Science and Technology Group visited the Cupids Green Recycling Centre.

Cupid Green is a very large site where all materials for recycling arrive to be sorted into separate categories before being sent elsewhere for further processing. There were 20 to 25 separate bays in a very large yard, with each one holding a different category of material. These ranged from innocuous things like tree branches, through cans and plastics, to potentially dangerous substances, such as solvents and paints, held in large fireproof containers. We passed by a small shed (Hut 13) where 'roadkill' is kept by law in a freezer for 2 weeks, before being disposed of. Fly-tipping, of materials that are difficult to dispose of, is a big problem. We were shown a huge tree-trunk that had just been dumped 'down a lane'. CCTV cameras are placed in popular dumping spots.

Some categories of materials are able to be sold at a profit - such as baled and compressed aluminium cans at £850 per ton. Others cost us, as ratepayers, to be processed elsewhere. For example it costs us £3-50 each to process mattresses elsewhere. Overall the running costs of the centre seem to roughly offset by the materials sold. However the capital costs of the heavy equipment needed to collect and process the materials are heavy, and probably not covered. For example a simple waste collection vehicle costs around £80,000, while a more sophisticated vehicle costs £180,000. They have 34 vehicles in total. A specialised vehicle-cleaning rig cost £100,000.

We were shown the MRF (Material Recovery Facility), which is a rather noisy mainly-automatic piece of plant machinery that separates plastics, aluminium cans and steel. These are fed as a mixture into one end of the process and emerge from the building as separate bales of compressed plastics, aluminium, and steel. It was interesting to see the point in the machine where mixed plastics and aluminium cans are separated by the cans leaping forward by half a metre away from the plastic. This is done by an eddy current induced into the cans causing a repulsive effect.

We were told that landfill sites are rapidly running out, and costs are rising faster than expected. There is a plan to build a large incinerator ('energy from waste') at Hatfield in 2016.