Eddy Current Separator

An Eddy Current Separator (ECS) is a machine that is used to separate and recover non-ferrous metals such as aluminium, copper and brass from non-metallic material in a waste stream.

Eddy Current Separator Magnet Rotor and Splitter. Image: OKAY Engineering.

Overview

An Eddy Current Separator (ECS) is a machine that is used to separate and recover non-ferrous metals such as aluminium, copper and brass from non-metallic material in a waste stream. Material is fed onto the conveyor of the separator, which moves it across the magnetic rotor, situated underneath, to result in separation. The two resultant streams discharge into different bins/compartments with the aid of the splitter which divides the non-ferrous metal from the non-metallic waste such as paper, plastic, wood or automotive shredder residue (known as shredder fluff). This process is usually employed after magnetic separation has removed the bulk ferrous fraction from a scrap material stream.

The Magnet Rotor

The key component is the magnetic rotor, which is a series of permanent rare earth magnets mounted on a support plate attached to a shaft. The magnetic rotor is surrounded by, but not attached to, a non-metallic shell which supports the conveyor belt. This allows the rotor to spin independently and at a much higher speed than the non-metallic shell and belt.

Stated Benefits

• Very high hit rates
• Very high purity rates
• Compact and flexible
• Removes ranging sizes of non-ferrous metals

The Process

Eddy Current Separator Diagram. All Rights Reserved. Schematic Diagram of an Eddy Current Separator	1. The waste stream is fed onto the conveyor belt and is transported towards the magnetic rotor end.
	2. When a piece of non-ferrous metal passes over the magnetic rotor, the magnets inside the shell rotate past the metal at high speed which forms eddy currents to create a magnetic field around the piece of metal.
	3. The polarity of that magnetic field is the same as the rotating magnet, causing the non-ferrous metal to be repelled away from the magnet.
	4. This repulsion makes the trajectory of the non-ferrous metal greater than that of the non-metallic, allowing the two material streams to be separated.