“Turnkey solution particularly attractive for us”
When opting for Krones, Mpact adopted an approach of cautious due diligence. “Before we made the investment, we carried out detailed research,” explains John Hunt, Managing Director of Mpact Recycling. “We talked to operators of recycling systems, converters and beverage producers all over the world and looked at quite a few different models. The key criteria for placing the order with Krones was FDA approval, plus the system’s relatively favourable water and energy consumption. Krones was able to offer the PET recycling capability as a complete system, and not just delivering individual parts.” Mpact carefully reviewed the system Krones was proposing. “The washing module’s technology is excellent. Here, in our view, Krones is able to benefit from its long years of experience with bottle washers. And the decontamination module seems very dependable to us too. With Krones offering the front end as well, the system is an attractive turnkey solution for us,” says Ronald Fairbanks, General Manager Mpact Polymers. “Taking a long-term commercial view, the Krones recycling system was the best solution for us.”
MetaPure bottle-to-bottle PET recycling system at Mpact:
- Front end: The PET bottles, delivered in bales, are pre-sorted, coarsely cleaned and crushed.
- Washing module: The PET flakes are intensively cleaned, and foreign substances removed.
- Decontamination module: Food-hazardous contaminants are removed and the flakes turned into pellets.
Stage 1: Front end
In the facility’s courtyard, the PET bottles from the collection points are delivered in bales. The material is introduced to the front end, which opens them up in a bale-breaker to distribute bottles evenly on the conveyor. The first metal removal is performed using a permanent magnet to remove ferrous metal. The next unit is a ballistic separator, which in two stages removes flat contaminants like foils from the bottles, and lighter ones like dirt, dust and glass, etc. In the de-labeller unit, the containers are now fed between two drums, which mechanically remove labels, which are then separated out and disposed of in skips. A cascade-structured near-infra-red (NIR) sorting station detects coloured PET bottles and foreign plastics, and ejects them. At the end of this cascade, only transparent and light-blue PET bottles are then passed to the downstream process. As part of a dual checking system, the NIR sorting stage is followed by a manual sorting station. At the grinders, the final station in the front end, the bottles are shredded into small flakes.
“Thanks to dry removal of labels and dry grinding, the washing process has significantly lower water and energy consumption, in fact the water consumption is running at approximately 2.5 litres per kilogram of rPET, which is about 40 per cent lower than the industry’s standard figure,” explains Ronald Fairbanks.