How does an Eddy Current Separator work?

An Eddy Current Separator is basically a device used to separate non-ferrous metals (aluminum, copper, tin, etc) and waste from each other. Prior to the use of an eddy current separator, it’s expected that ferrous and non-ferrous metals have been separated already using magnets. The final separation occurs with the help of eddy currents generated by the machine.

In this article, we’ll explore the intricacies of how exactly an eddy current separator functions. However, before we get into that, you might be wondering exactly why we need to go through the trouble. Why is it so important to separate non-ferrous metals from waste?

Well, read on and find out why we use eddy current separators to begin with.

eddy current separators

The Reason Why 
1. A large portion of waste discharge these days contains metals of various sorts. As you may well know, metals can be quite valuable. As such, it’s important to retrieve them for the cash value.
2. The waste has to eventually be dumped in landfills. As such, it’s important to take out anything that can be used, sold, or recycled (i.e., the metals), so as to minimize the volume of waste in the landfills.

How does an Eddy Current Separator work? 
Now that you know what’s an eddy current separator and why it’s used, let’s get into the details. It’s quite complicated to explain all the principles that go into making an eddy current separator work, so try and keep up.

  1.  First, the ferrous and non-ferrous metals have to be separated using special magnets. This is done because ferrous metals tend to heat up within eddy currents, thus potentially damaging the machine’s conveyer belt
  2.  The material with the non-ferrous metals and the waste is then fed onto the conveyer belt of the machine. It moves along till it reaches the magnetic rotor, and that’s where they get separated.
  3. The material is discharged into a large compartmentalized housing. The waste falls limp into one portion, and the non-ferrous metals shoot out and fall into the second compartment.

The Principle 
The most important piece of the eddy current separator is the magnetic rotor installed at the end of the conveyer belt. It’s kept inside a non-metal drum, where it rotates at the speed of 3000 revolutions per minute. The outer non-metallic drum rotates at the speed of the conveyer belt.This movement induces an electric current into the conducting non-ferrous metals. The current creates a magnetic field which is in opposition to the magnetic field created by the rotor, and this helps repel the non-ferrous conducting metals away from the magnetic rotor.The non-metal wastes don’t react to the magnetic field and drop into the compartment closest to the conveyer belt. The metallic wastes get shot ahead and thus drop into the further compartment.As you can probably tell, an eddy current separator is one of the most effective waste recycling equipments. I hope this article has given you some clarity on what it is, how it works, and why it’s so important.