Chemistry · Ch 1 — Metallurgy
Magnetic Separation
Magnetic Separation
Magnetic separation exploits a DIFFERENCE IN MAGNETIC PROPERTY between the ore and its impurities, and applies specifically to FERROMAGNETIC ores -- ores that are themselves strongly attracted by a magnet -- or, in the reverse situation, to a magnetic IMPURITY that needs to be removed from a non-magnetic ore.
A worked example of each direction is given: tin stone (cassiterite, SnO2, non-magnetic) can be freed of magnetic wolframite impurity by this method, since the wolframite is pulled away by the magnet while the tin stone is not; and, conversely, ores such as chromite and pyrolusite, which are themselves magnetic, can be separated away from non-magnetic siliceous gangue. …
What this figure shows. A schematic of a magnetic separator: powdered ore is fed from a hopper onto a moving belt that runs over two rollers, one of which (the right-hand roller) is a magnetic wheel; as the belt passes over the magnetic roller, the magnetic ore particles are attracted and fall close to the roller in a heap labelled 'Magnetic ore', while the non-magnetic ore particles are flung further away and fall in …