A DISCUSSION
ON
MAGNETIC SEPARATION
By :- SHISHIR VIKRANT (495/08)
&
RAJESH PASWAN (290/08)
INTRODUCTION
# Magnetic separation is a process in which
magnetically susceptible material is
extracted from a mixture using a magnetic
force.
# Since 19th century magnetic separation
processes have been used to concentrate and
separate minerals.
INTRODUCTION
# By combining the different forces of magnets with
gravitational or frictional forces a separation of
mineral particle is possible. Two or more products
are obtained depending on their commercial
value, these products are concentrates, middlings,
or tailings.
#
Ferromagnetism,
paramagnetism
and
diamagnetism are the three important properties of
the minerals which is used for Magnetic separation.
APPLICATION OF MAGNETISM AS SEPARATOR
Basically Magnetism is used for five distinct type of separation :
1. For the removal of tramp iron in coarse and
intermediate- crushing circuits, as a protection to
the crushing machinery.
2. For the concentration of magnetite ores.
3. For the concentration of iron ore other than
magnetite, after preliminary conversion of iron
minerals to artificial magnetite by suitable
Roasting.
4. For the removal of small quantities of iron ore
minerals from Ceramic raw materials.
5. For the concentration of slightly Paramagnetic
minerals such as those of Manganese,
tungsten, chromium, tin, zinc, titanium, etc.
ELEMENTS OF DESIGN OF MAGNETIC SEPARATORS
1. Production of suitably converging magnetic field.
2. Even feeding of ore particles as a stream or sheet.
3. Control of speed of passage of ore through the
magnetic field.
4. Avoidance and / or correction of occlusion or non
magnetic material between or within magnetic
flux.
5. Provision of suitable means for disposing of
separated products.
6. Provision for production of a middling.
7. Elimination or reduction to a minimum of moving
(wearing ) parts.
CLASSIFICATION OF MAGNETIC SEPARATOR
It can be classified according to the medium in which
the separation is made, the mode of the presentation
of the feed, the mode of disposal of the products, &
whether the magnets are stationary or moving.
IMPORTANT TYPES OF MAGNETIC SEPARATOR
1.
2.
3.
4.
5.
6.
7.
EDISON SEPARATOR
BALL NORTON SEPARATOR
MAGNETIC DRUM SEPARATOR
ROLLAR TYPE SEPATOR
GRAVITY FEED MAGNETIC SEPARATOR
MAGNETIC COOLENT SEPARATOR
WET DRUM SEPRATOR
EDISON SEPARATOR
Edison separator consists of a bar
magnet . The ore as thin streams falls
in front of the poles, susceptible
particles being deflected inwards &
nonsusceptible particles continuing
to fall undeflected.
This separator was not wholly
successful because of inability of
control flow of solid in a thin sheet,
& because of lack of control over the
speed of the falling particles.
Ball Norton Separator
Unlike most magnetic separators which are used to remove relatively
small amounts of metal, the Ball Norton Separator is designed to
handle large amounts of ferrous material - removing other
undesirable elements. A unique combination of alternating
magnetic poles and vibratory conveying works to clean the magnetic
material. Applications include foundry shot, crushed borings, slag
and magnetic ores.
MAGNETIC DRUM SEPARATOR
Magnetic drum separators are important
magnetic separators that removes ferrous metal
from dry bulk products in free-flowing
processing systems. They are self cleaning unit
consisting of drums and housing normally of
stainless steel. The magnets used by the
magnetic drum separators are either ceramic
magnets or rare earth magnets. The magnetic
drum separators are available both in single or
double drum configuration.
How it Works?
The processing materials enters the top of the magnetic
drum separator and flows across the surface of the drum.
The rotatory drum in the magnetic field captures the
ferrous tramps whereas non ferrous falls free from the
drum into the cleaned material flow. As the drum rotates,
the ferrous metal so captured is carried past the diverter
and released outside of the magnetic field.
Types
Magnetic drum separators are of different types like:
•Electro drum separators
•Wet drum separators
Double drum separators
Applications
The magnetic drum separator is ideal for separating iron particles from
granules & powders It is widely used in the following industries:
•Glass
•Ceramic
•Chemical
•Fertilizer
•Plastic
•Food industry
•Iron and steel slag treatment
•Reduced pyrite ash separation
•Calcined ilmenite production
Metal powder production
Roller type magnetic separator is
meant to separate ferrous contaminants
from the flimsy magnetized dry
granular metallic and nonmetallic
materials. Roller type magnetic
separator has wide application in
industries and mineral technology. The
separator uses high powered rare earth
magnets with very low dimensional
tolerance. The other components of the
machine are conveyor and vibratory
feeder. The magnetic rolls are available
in different widths and magnetic
strength
How it Works?
The material is discharge on the belt by the feeder. The magnetic roll
is enveloped by the conveyor. The para and ferro magnetic
ingredients remains stuck to the belt whereas non magnetic
ingredients passes freely at the end of the conveyor.
Applications
Roller type magnetic separator finds applications in the following areas
like:
•Glass industries
•Abrasive refractory
•Quartz cleaning
•Upgrading of graphite
•Recovery of metals from slag removal of ferro silicates
•Chemical industries
Gravity feed magnets separates ferrous tramp metal
through gravity system. These magnets are constructed
out of welded stainless steel and are available in stainless
steel structure. The gravity magnet comes in different
shapes and sizes and are ideal for narrow chute
applications. Gravity feed magnets are normally used in
vertical flow system.
Applications
Gravity magnetic separators have different industrial and commercial
usage. They are applied in industries like:
•Food industry
•Chemical industry
•Grain processing industries
Pharmaceutical industries
MAGNETIC COOLENT SEPARATOR
Magnetic coolant separator is a
device which cleans the coolant
liquid of very fine ferrous particles.
It removes the iron chips from the
milling or grinding liquid. It is light
and compact structure having
strong magnetic power which can
remove very fine ferrous particles.
For precise grinding operations
uninterrupted flow of oil is must.
The coolant magnetic separator
ensures the uninterrupted flow of
the liquid.
WET DRUM SEPARATOR
Features
 Wet drum magnets have high magnetic recovery and
discharge.
 The feed slurries recover the magnetics.
 Available in single or multiple drum applications.
 Recover magnetic solids in as clean a magnetic
concentrate as possible .
 Permanent magnet assembly eliminates coil burn-outs .
 The magnet / pole elements are bolted to a mild steel
shaft.
 The drum is made from thick stainless steel for long
service life.
 Wet drum separators are available in different
configuration like single drum,double drum and multiple
drum. In double drum two separators are arranged back
to back with a common feed back.
Applications

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Glass industry
Chemical industry
Plastic industry
Mining industry
Food industry
Pharmaceuticals industry
Foundry industry
REFERENCES :
1. Principles of Mineral dressing by A. M. Gaudin
2. www.themagnetguide.com
3. www.en.wikipedia.org
4. Mineral processing design & operation by
A.Gupta & D.S. Yan
THANK YOU