Separating Ferrous Metals When Recycling Printer Cartridges – Magnetic Separation

Magnetic separation improves recycling applications in many ways—namely, by improving efficiency and increasing the amount of good material that is able to be recovered. Magnetic separation also allows for more unique recycling operations to take place, such as the recycling of printer cartridges. At BCMY Ltd., a recycling company based in the United Kingdom, a high strength rare earth drum magnet is used to separate ferrous metal from shredded laser printer and toner cartridges. This drum magnet protects downstream shredders from damage metal contamination can cause and maximizes the purity of the end recycled product.

Recycling Printer Cartridges

BCMY Ltd. receives used printer cartridges from the United Kingdom as well as greater Europe. It is one of the UK’s premier processors of used printer cartridges, although currently, only 15% of the 250 million ink cartridges and 25% of the 40 million toner cartridges used in Western Europe are recycled. Sadly, most used cartridges end up in landfills. Not only do cartridges take over 1,000 years to naturally decompose, but they also pose a threat to ground water pollution.

In order to process used printer and toner cartridges for recycling, the processing facility must possess specialized knowledge. Printer and toner cartridges are classified as hazardous materials due to the explosion risk presented by the small particle size of the toner dust.

The Cartridge Recycling Process

Once BCMY receives a shipment of used laser printer and toner cartridges, the company first assesses whether the item is reusable or needs to be completely recycled. Of all the cartridges BCMY receives, approximately 62% are reused. However, due to the growing number of low-quality replicas and compatibles (approximately 15% of materials received), as well as a growth in remanufactured cartridges (approximately 20% of cartridges received), the number of cartridges designated for internal recycling is increasing.

Despite the increased competition coming from the replicas/compatibles market, specific virgin empty cartridges remain in high demand. However, the overall percentage of collected reusable cartridges is falling. As a result of tighter waste legislation and a reduced industry capacity to deal with non-reusable cartridges, there are now more limited disposal options for high volume cartridge producers. Landfills are no longer a legal option for high volume producers in Europe, so now waste to energy plants have become popular as an alternative. Still, this option also comes with environmental concerns.

At BCMY’S UK plant, the company specializes in physical recycling of non-reusable cartridges. First, any hazardous toner dust is removed, leaving behind a mixture of plastic and metal. Next, empty cartridge shells are fed into a slow-speed shredder to reduce their size and help free any trapped particles before they move up an incline conveyor and onto the surface of Bunting’s powerful drum magnet. The drum magnet is able to separate all magnetic materials, including steel components, springs, small ferrous metals, and even ceramic magnets that may be present in the recycled material. After the drum magnet cleans the material of ferrous metal, the cleansed plastic fraction will be shredded again, then passed over an eddy current separator to separate aluminum and other non-ferrous metals.

Drum Magnet Separates Metal

A drum magnet features a stationary magnetic element housed within a rotating stainless-steel shell. In the drum magnet used in BCMY’s recycling facility, the magnetic element is constructed with powerful, permanent, rare earth neodymium magnets. The drum magnet is mounted within a dust-enclosed housing and driven using a direct shaft-mounted electric motor.

Material is moved via an inclined conveyor leading to the drum magnet’s feed hopper. After entering the hopper, material will then cascade down onto the drum magnet’s rotating shell. Here, the powerful magnetic field will attract and hold ferrous metals, carrying them underneath the drum magnet and out of the range of the magnetic field where they then fall into a designated container. Plastic and other non-magnetic materials will not be affected by the magnetic field and follow a standard trajectory into a separate collection container.

At BCMY’s plant, each cartridge contains approximately 42% metal. This metal, after being recovered, is then resold for further use. Recovered plastic, which can include PS, ABS, PET, PP, POM, and HDPE, is also resold for use in various other applications, including goods such as plastic planking for outdoor decks. Even the hazardous toner powder is collected and reused as a colorant in plastic manufacturing, as well as being used as a filler in tarmac and marine paint for boats.

Bunting’s drum magnets are highly effective in a wide range of recycling applications. To learn more about drum magnets and other magnetic separation solutions for recycling, contact Bunting today.