Ask any trash collector and they will tell you: People will throw absolutely anything in the trash. Never mind if it contains harmful materials that could pollute the environment or poison the water table.
Today, one of the most dangerous items that commonly makes its way into the trash pile are printed circuit boards, those tiny, flat green electronic devices that are found in practically every electronic device — from radios to computers, TVs to smartphones.
Most people don’t realize that printed circuit boards actually can contain highly toxic substances — including palladium, gold, silver, copper and other hazardous materials — that cannot safely stored in landfills.
Long-Term Dangers
Over time, these substances can be exposed to water and leach into the ground, where they can potentially cause damage that can last for hundreds of years. And if they make their way into a public water supply, they can cause even more problems.
Catching printed circuit boards before they make their way into the ground, where they can cause harm for many centuries to come, is a challenge for many recycling companies, especially those that frequently work with waste electrical and electronic equipment (WEEE). But now a new technology that can identify, capture and remove printed circuit boards via a new type of magnet has been discovered … completely by accident.
An Accidental Discovery
Bunting Mechanics — based in Newton, Kansas — had been working with an UK plastics recycling company to develop new ways to pull valuable abraded and shredded stainless steel from recycled materials as it moved down an conveyor line. The company installed a High Intensity Separation Conveyor (HISC) that featured an exceptionally strong magnetic head pulley.
During on-site tests, Bunting technicians determined that the experiment worked — the magnet was able to attracted the weakly magnetic materials the recycler was seeking to recover. But it also unexpectedly attracted another potentially harmful byproduct: Printed circuit boards.
Global Applications
Now Bunting is hoping that the technology can be used more widely to identify and remove the environmentally-unfriendly circuit boards from recycled materials worldwide, according to a company news release.
Bunting’s HISC Magnetic Separator typically is used after traditional recycling magnetic separation and eddy current separation pulls the most common metals — such as iron and steel — from recycled materials. It was intended to pull out weakly magnetic materials such as stainless steel so that clean recycled materials like UPVC window frames and recyclable plastics could be the end product.
HISC Magnetic Separators have a much stronger magnetic field that other types of magnets, allowing them to separate metals with very low magnetic susceptibility.