How is an Eddy current separator actually getting the particle fly off?

Question

I am currently trying to understand the eddy current separator on a physical level, but unfortunately I have a few uncertainties to resolve. I don't quite understand what is ultimately the reason why a particle that is electrically conductive can take off. I have two explanations, but I am not sure if either of them is correct:

First explanation: 
When a particle is moved towards a magnet by a conveyor belt, the magnetic field that passes through the particle becomes larger and larger.  Because a particle wants to keep a magnetic field always constant, it tries to create a magnetic field which points against the magnetic field of the magnet. Are the opposing magnetic fields the reason why a particle that is electrically conductive takes off?
Second explanation:
The magnetic field and the velocity create a Lorentz force that moves the electrons into one half of the particle and the polarity combined with the magnet from the magnetic drum causes the particle and the magnet to repel each other.

Many thanks for your answers

niels nielsen · Answer

In the case of aluminum in an eddy current separator, the cause is as follows.

There is an electromagnetic coil in the separator drum which is carrying an AC current. This induces eddy currents to flow within the pieces of scrap aluminum going by the outside of the drum. Those eddy currents generate a magnetic field of their own which opposes the AC field generated by the coil, and thereby a repulsive force is developed between the aluminum bits and the coil inside the drum. This kicks the bits out of the conveyor stream.

This principle is used in solenoid actuators that run on AC. Inside the solenoid coil is a rod of aluminum which is attached to the mechanism that the coil actuates. When the coil is switched on, it pushes the aluminum rod out of the coil.

How is an Eddy current separator actually getting the particle fly off?

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