PVC compounder EcoVyn Ltd installed two Bunting Drawer Filter Magnets to remove ferrous metal contamination from plastic waste. Since installation, EcoVyn has reduced its waste by 94%.
EcoVyn Ltd is at the forefront of PVC compounding and brings pioneering new technology to the market place. They offer one of the most advanced and innovative production processes in the UK producing reprocessed, blended and virgin compounds for a variety of applications.
Blending Reclaimed Plastic Waste
EcoVyn first met Bunting at the Interplas international plastics exhibition in September 2017. The company use a high proportion of plastic waste, of which 80% is post-consumer. Presently, EcoVyn processes 1000 tonnes per month of good quality reclaimed plastic waste, which they plan to increase to 16,000 tonnes per annum. The cleansed plastic waste is blended into virgin material, resulting in a 90% output of grade A product. Waste generated during the manufacturing process is also recycled, leaving less than 1% being discarded.
However, plastic waste is often highly contaminated with metal. Metal detectors were already installed to remove the metal contamination, but the reject rate was very high with over 60 tonnes of waste being generated, of which a high proportion was good quality plastic.
Issue of Metal Contaminated Plastic Waste
At Interplas, EcoVyn explained the problem to the Bunting team who agreed to conduct a site review. During the review, it was concluded that easily removable magnetically-susceptible metal could be removed, leaving the metal detectors to detect and separate non-ferrous metals. This would then significantly reduce the number of metal detector rejections and, therefore, the amount of waste generated.
After a review of the process, Drawer Filter Magnets were recommended to be installed between the screw conveyor transporting the 8-10mm sized infeed material and the metal detector. The metal-cleansed material would then pass onto a pulveriser before continuing through the process.
- Technical information: Magnetic Separators and Metal Detectors used in the plastics industry
Drawer Filter Magnet – A Plastics Industry Standard
The Bunting Drawer Filter Magnet is used widely in the plastics industry and enables the simple and effective removal of ferrous metal from free-flowing materials. The Drawer Filters installed at EcoVyn have two rows of high strength Rare Earth Neodymium Magnets. The top row has two Tube Magnets with three in the second row aligned to sit below the gap in the top row. This ensures that all the product strikes at least one of the Tube Magnets, where ferrous metal is attracted by the strong magnetic field and captured.
After the installation of Drawer Filter Magnets, the amount of waste was reduced from 60 tonnes to 4 tonnes.
Since installing the Drawer Filter Magnets, EcoVyn has established that a 20 minutes cleaning frequency is required, highlighting the high level of metal contamination commonly found in plastic waste. The ferrous metal found captured on the Tube Magnets ranges from small fine ferrous dust to nails, washers, steel sheet shards and electrical capacitors.
Following the installation of the Bunting Drawer Filter Magnets, controlled laboratory tests have been conducted at Bunting’s Recycling Test Facility in Birmingham which indicated that 99.9% of all ferrous metals had been removed.
The final plastic product produced by EcoVyn is then used to manufacture products such as pipe, internal windows, beading, picture frames, and shoe soles.
- Related technical article: 3 Metal Items Contaminating Plastic Waste