In 2019, STADLER UK Limited was appointed by Viridor as one of two main contract partners for the £15.4m upgrade of its Masons Materials Recycling Facility (MRF) near Ipswich, modernising the facility as part of a ten-year Viridor-Suffolk County Council contract renewal. Viridor runs the MRF on behalf of the Suffolk Waste Partnership.
Having already worked together on several projects around the world, STADLER and TOMRA worked in close collaboration from the earliest stages of the tender enquiry to ensure the plant and equipment met Viridor’s specific requirements.
By investing heavily in the plant upgrade, Viridor has been able to transform its operations, increasing capacity from 65,000tpa to 75,000tpa, equivalenting it to 17 tonnes per hour.
The plant is now operating at full capacity and at optimum processing levels, while output quality has also improved considerably due to the new TOMRA equipment installed during the upgrade.
Masons’s infeed material is commingled dry mixed recyclables (not including glass) from Suffolk County Council. The material is first processed using brand new mechanical separation equipment, including a dosing drum, a STADLER PPK ballistic separator, a screening drum, STADLER STT 2000 ballistic separators, overband magnets and eddy current separators.
Following mechanical separation, the material (apart from fibre) then goes through an air separation process before arriving at the newly installed TOMRA AUTOSORT® optical sensor-based sorting units.
Prior to the upgrade, three TOMRA optical sorters were in place at the MRF. These were replaced by 11 new TOMRA AUTOSORT® units. As one of the existing units was only four years old, TOMRA simply uploaded the latest software.
The units have been programmed to sort and recover mixed fibre (cardboard, mixed paper and newspapers and pamphlets), and to sort mixed plastics by polymer into high purity single stream plastics (PET, HDPE, hard plastics, film, pots, tubs and trays).
Once the MRF’s infeed material at has been processed by the relevant AUTOSORT® units, it is given a final quality control check before being baled ready for transportation to end customers, all of whom are UK-based. Any material that is left once all the target fractions have been recovered is sent for energy recovery or to landfill.
With the new mechanical and sensor-based equipment in place, Viridor has increased throughput as the plant can cope with a higher tonnage of infeed material. In addition, market-leading purity of target fractions, eg 98.5% purity on newspapers and pamphlets and 95%+ for polymers such as PET, HDPE and mixed plastics
The company says it is cost savings derived from sorting PET and HDPE. Previously this material was sent to Viridor Rochester for reprocessing but now it can be reprocessed on-site, cutting the carbon footprint and saving on reprocessing costs.
Steven Walsh, Sales Engineer at TOMRA Sorting Recycling, said: “We were delighted to work with STADLER on this project, having already worked with them on a number of other projects nationally and internationally. Prior to the refurb, this Viridor site could only sort mixed plastics for further processing at the Rochester PRF and it was extremely manual sorting focused, with hand sorting used for all cardboard and refined paper grades. Now though, Masons is among the most highly automated plants in the UK and by integrating TOMRA equipment and benefitting from TOMRA’s technical expertise, Viridor can capture superior quality materials ready to feed back into the circular economy.”
“This is by far the largest investment in a UK MRF in recent years. Viridor is heavily focused on developing opportunities to put quality recycling materials back into the economy where they belong. This starts with viewing waste as a resource, rather than rubbish, and, thanks to Suffolk’s commitment to recycling, and our investment in the Masons MRF, we are well positioned to make the most of the county’s recycling opportunities and to sell that material onto UK-based end customers,” explained Viridor Recycling Director, Derek Edwards.
“The Masons investment plan has been specifically designed not only to achieve greater capacity but to match its output quality with market requirements. The plant has the same infeed material as before, but can now cope with an additional 10,000 tonnes of material per annum. We’re delighted with the performance of the plant and its equipment since the upgrade was completed.”