Magnetic Separation Flashcards
(25 cards)
is a physical separation of
particles based on the magnetic property of the mineral particles.
Magnetic Separation
- have a very high susceptibility to
magnetic forces and retain some magnetism when removed from the
magnetic field, ex Magnetite.
Ferromagnetic Minerals
- are repelled along the lines of magnetic
force to a point where the field intensity is smaller, ex. Quartz and
feldspar.
Diamagnetic Minerals
are weakly attracted by magnetic field,
ex. Ilmenite, Rutile, Wolframite, Hematite
Paramagnetic Minerals
It is achieved by simultaneously applying a magnetic force on all particles of
an ore which acts on magnetic particles and a combination of forces which acts
in a different direction and affects both magnetic and nonmagnetic particles.
Magnetic Separators
are magnetized steel bars which retain magnetism
indefinitely.
Permanent Magnets
alloys produce a magnetic field at a constant level
indefinitely after initial charging.
Special permanent Magnet
are those used to remove tramp iron and protect
the handling and processing equipment.
Tramp Iron Magnetic Separator
in the form of barium and strontium
ferrites, and rare-earth-cobalt permanent magnet alloys are also being in use.
Newer Ceramic permanent Magnet
bars of soft wrought iron, soft steel or cast iron are
magnetized by electric currents through the insulated copper or aluminum wire
windings around the iron bars.
Electromagnet
are those used to separate the bulk of magnetic materials from a stream of ore. They are classified into dry and wet separators which may
further classified into low- and high-intensity separators.
Concentrators
magnetic separators that are used to remove small quantities of
deleterious magnetic material from a product.
Purifiers
- the concentrators that remove magnetic material from a product and return to the process.
Reclaimers
are common low-intensity dry magnetic separators.
Drum Separators
- Consist of a rotating non-magnetic drum containing either permanent or electromagnets
- Magnetic particles are attracted by the magnets, pinned to the drum, conveyed out of the field and discharged while the nonmagnetic
particles are discharged unaffected
Drum Separator
are high intensity dry magnetic separators.
* Consist of a horseshoe magnet faced by an iron bridge bar or keeper and
of two rolls, one opposite each pole.
Induced Roll Separator
are high intensity dry magnetic separators.
* Consist of a horseshoe magnet faced by an iron bridge bar or keeper and
of two rolls, one opposite each pole.
Induced Roll Separator
Non-magnetic particles are thrown off the roll into the
tailings compartment, whereas magnetics are
gripped, carried out of the influence of the field and
discharged.
Induced Roll Separator
are high intensity dry magnetic separators.
* Consists of two or more horseshoe electromagnets arranged with poles of opposite sign in apposition, one electromagnet being below and the other above the feed belt.
* This concentrates the field and attracts the paramagnetic minerals toward the wedge-shaped poles.
Cross-belt separator
is the modification of the cross-belt separator wherein discs revolve above a conveyor belt and are magnetized by induction from powerful
stationary electromagnets placed below the belt
Disc Separator
WET MAGNETIC SEPARATOR
most common low-intensity wet magnetic separators.
* Magnetic particles are lifted by the magnets and pinned to the drum and are conveyed out of the field leaving the gangue particles.
* Water is introduced into the machine to provide a current which keeps the pulp in suspension.
Drum Separator
Types of Drum Separator
- are used when clean concentrate is
required from relatively coarse material such as heavy medium
recovery systems.
Concurrent Type Separators
Type of drum separator
are used in the roughing
operation of larger tonnages
Counter-rotation type separator
Types of Drum Separator
are designed for finishing
operation on relatively fine material
Counter-current type separator
