The physical separation
In physical separation, the differences in physical properties between components necessarily unlocked such as the specific gravity, shape, magnetic, electrical or optical properties are exploited either intrinsically or differentially.
The specific gravity is exploited through separation known as gravimetric, which brings together different techniques:
- Dense media which use a liquid medium in which components float or sink
- Techniques using fluidisation of components and where gravity is the driving force for separation (jig, spiral, shaking table, pneumatic table, etc.).
- Centrifugal techniques more suited to very fine products thanks to much stronger acceleration generated by centrifugal force (Knelson, Falcon, MGS, etc.).
The difference in the magnetic susceptibility of components is exploited through magnetic separation.
The difference in electrical conductivity, sometimes coupled with magnetic properties, is exploited through electrostatic separation.
Finally, optical recognition sorting techniques aim to separate a mixture of particles based on one of the physical recognition criteria which represents the shape, colour, emission or absorption of radiation.
