Friday, July 21, 2017

The Role of Magnets in the Recycling Process

“Paper and paperboard have always had high recycling rates for bulk newsprint, office paper, and old cardboard.  Metal, however, is the material with the second-highest MRF-related recycling rates at over one third.”
Machines in recycling facilities designed for the purpose of separating recyclables are made up of several components.  Among these are different types of magnets to sort and handle metallic materials.  The most popular and widely used are overbelt magnets, electromagnets and eddy current magnets.

Overbelt magnets are magnets placed above a conveyor belt that recyclable materials run on.  As the conveyor passes under the magnet, ferrous metals are captured.

Electromagnets are magnets that can be controlled by a flow of electricity that, when turned on, causes them to become magnetic.  When the electric current is turned off, however, they are no longer magnets.

These are extremely useful in mixed-waste recycling facilities because they can be passed through a pile of recyclables, turned on and come out full of metallic material to be stockpiled until it’s ready to be transported.

An eddy current is the current is induced in little swirls ("eddies") on a large conductor.
If a large conductive metal plate is moved through a magnetic field which intersects perpendicularly to the sheet, the magnetic field will induce small "rings" of current which will actually create internal magnetic fields opposing the change.”

In other words, eddy current magnets create a negative charge repelling certain metal materials and, therefore, causing them to fling away from the magnet and be collected in a bunker.
This is just one component of the fast, efficient sorting machines making single stream recycling as easy as ever before.

1 comment:

  1. I didnt even knew that magnets plays an important role in recycling. I always thought they are for playing or may be in science. Thanks for sharing