When you next take out your household recycling bin, spare a thought for the hard and unseen work of the humble magnet. We all take our recycling duties pretty seriously these days, and for good reason. Our planet would otherwise be literally buried under our waste if we didn’t have some sophisticated recycling methods to handle the mountains of waste we generate. That’s where magnets play a crucial role.
Magnets are involved in all stages of the recycling process, helping to separate and recover valuable metals from waste. From the moment our recyclables leave our bins to when they are processed into new products, magnets are involved at several key stages.
It starts at your place. When recyclables are collected from bins, they are transported to a materials recovery facility (MRF). Here, waste is sorted into different categories - paper, plastic, glass and metals. Magnets are used to separate ferrous metals - which contain iron - from non-ferrous metals, such as aluminium and copper.
It’s at the recycling centre where the power of magnetism does the heavy lifting. Super strong electromagnets and permanent magnets are used in conveyor systems to extract ferrous metals.
Magnetic separators are set up in a range of configurations to grab hold of that waste metal. One of the most useful applications is the Overhead magnet, which is suspended above conveyor belts to pull out the ferrous metals as waste moves underneath.
Another configuration of these powerful magnetic devices is the drum magnet. Rotating drums attract and separate ferrous metals while allowing non-magnetic materials to continue along the belt.
Eddy current separators are not technically magnets, but these devices use magnetic fields to repel non-ferrous metals, like aluminium, from the waste stream.
Magnetic swarf cleaners are one of the most valuable magnetic devices in the recycling chain, swooping up what’s known as swarf - tiny metal shavings, dust and chips produced in metalworking industries and manufacturing facilities.
Magnetic swarf cleaners work by collecting metal debris. The magnetic devices can be handheld or automated magnetic sweepers, removing swarf from workshop floors, machinery and cutting fluids.
In industries that produce a lot of metal shavings magnetic swarf cleaners are used at the source to minimise waste and improve safety. As well as the handheld magnetic sweepers used to pick up swarf from factory floors, magnetic swarf cleaners can also be fixed to forklifts or workbenches to continuously collect stray swarf. Swarf cleaners are also attached to magnetic conveyor belts to help move swarf to collection points, preventing accumulation in unwanted areas.
Magnetic filters another process used to remove metal particles from industrial oils and coolants, preventing contamination and allowing the metal to be reclaimed.
Once collected, swarf is melted down and repurposed into new metal products. The recovered metals are cleaned, shredded and melted in furnaces. The molten metal is then poured into moulds or rolled into sheets to create new products, such as construction materials, car parts or packaging.
Magnets make metal recycling more efficient by reducing landfill waste, conserving natural resources by reducing the need for new metal mining and lowering energy consumption. Recycling metals requires less energy than extracting and refining raw materials and together all these outcomes justify the continued development of magnetic innovations in the recycling industry.
Recycled metals are used in countless applications, from new food cans to car frames and appliances. Magnets play a massive role in this vital industry, making metal recycling more efficient, cost-effective and environmentally friendly.