The 132,000 tonnes-per-year capacity facility, based in Wolverton, brings together mechanical treatment, gasification and anaerobic digestion under one roof.
It has been developed under a 15-year contract between Amey and Milton Keynes council signed in 2013, and will take in municipal refuse from households in the town.
According to Amey, waste delivered at the plant will travel along 1,300 metres of conveyor belts where it will be separated to ensure recyclables and organic materials are extracted.
The mechanical treatment technology has been designed by Stadler UK, to extract materials including plastics, bricks and rubble, cardboard, film and metals. Three grades of plastics – PET, HDPE and mixed plastics – will be separated through the near infrared sorting technology supplied by TOMRA Sorting Recycling.
From there, the residual element of the waste will undergo advanced thermal treatment while organics will be put through the on-site AD plant. Combined the process will produce 5.8MW for the National Grid.
Amey’s Peter Waller confirmed that the AD plant is “already successfully producing electricity following its testing phases” as well as creating compost-like output (CLO) for use on brownfield sites.
He said: “We first started work in 2014 so the testing of the mechanical treatment technology is a major step as we near the final stages of building MKWRP. The technology not only picks out any recyclable items, such as plastic bottles and metal cans, but it takes out food and biodegradable items too.
“The technology includes air knives which separate light items from heavy, as well as ballistic separators which sort flat items from those which roll around – helping it to recognise what type of waste its dealing with.
“It can also identify the difference between different plastics thanks to near infrared sorting technology, which will be able to process waste at up to seven tonnes per hour despite the plastics being dirty.”
When the plant becomes fully operational next year, Milton Keynes’ reliance on landfill is expected to drop to around 3%.
The commissioning phase will come as a welcome milestone for Amey and the council, after the firm’s sub-contractor Energos entered administration during the summer.
Energos had been appointed to oversee installation of the thermal gasification technology at the site, and at the time Amey confirmed it had “put steps in place” to ensure the insolvency did not affect delivery of the plant.