Two types of equipments can be discerned, induced rotor electromagnetic separator and permanent magnet separator.
The induced rotor electromagnetic separator consists of two separation stages. The first stage or low intensity module it is composed of one permanent magnet magnetic drum, low intensity and high gradient, which task is avoiding the entry of ferromagnetic parts to the next separation stage, where they could cause mechanical breakdowns.
The next separation stage it is composed of a high intensity module with several induced rotor cascade-style, capable of attracting and extracting the paramagnetic materials, distributed in one or two parallel lines of one to three rotors each.
It is the most powerful separation equipment where magnetic fields of up to 21.000 Gauss and a high gradient are achieved. Under these working conditions, very high magnetic attraction forces are produced on paramagnetic materials of very low magnetic susceptibility such as iron and manganese oxides, hematite, limonite, micas, etc.
The second-high intensity and permanent magnet equipment is designed to perform the extraction of weakly magnetic material, which as an impurity is among a dry material of fine grain size.
The separator consists of a vibrating feeder that receives the product and distributes it evenly and in a thin layer over a special antistatic and very thin belt.
The drive or motor roller of this belt is made up of an accumulation of Rate Earth permanent magnets with a very high magnetic power and with high permeability steel magnetic poles.
This result is the creation of a high intensity and very high gradient magnetic field capable of attracting very weak magnetic materials such as iron oxide, weak magnetic dust and a large amount of paramagnetic materials.
Each material grain size corresponds to certain optimum pole width and magnet width.
Upon arriving to the roller, the material transported by the belt is subjected to its magnetic field. The magnetic particles are attracted, accompanying the roller in its rotation and becoming loose under and behind the roller, with a fall that is clearly differentiated from that of non-magnetic material, which falls freely without any influence by the magnetic field.