A DISCUSSIONONMAGNETIC SEPARATIONPresented By:Gulfam Hussain
INTRODUCTIONMagnetic separators are used to separateeither valuable minerals from non-magneticgangue, e.g. magnetite fromquartz, or magnetic contaminantsOr other valuable minerals from the non-magnetic values.All materials are affected in some way whenplaced in a magnetic field, although with mostsubstances the effect is too slight to bedetected.
Materials can be classified into two groups.1. Diamagnetic Materials2. Paramagnetic MaterialsDiamagnetic are repelled along the lines of magneticforce to a point where the field intensity is smaller.The forces involved here are very small.Paramagnetic are attracted along the lines ofmagnetic force to points of greater field intensity.Examples of paramagnetic are ilmenite(FeTiO3), pyrrhotite (FeS), and manganese minerals.Some elements are themselves paramagnetic, suchas Ni, Co, Mn , Cr and Pt.The paramagnetic properties of minerals are due tothe presence of iron in some
APPLICATION OF MAGNETISM AS SEPARATOR1. For the removal of tramp iron in coarse andintermediate- crushing circuits, as a protection tothe crushing machinery.2. For the concentration of magnetite ores.3. For the concentration of iron ore other thanmagnetite, after preliminary conversion of ironminerals to artificial magnetite by suitableRoasting.4. For the removal of small quantities of iron oreminerals from Ceramic raw materials.
ELEMENTS OF DESIGN OF MAGNETIC SEPARATORS1. 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 themagnetic field.4. Avoidance and / or correction of occlusion or nonmagnetic material between or within magneticflux.5. Provision of suitable means for disposing ofseparated products.6. Provision for production of a middling.7. Elimination or reduction to a minimum of moving(wearing ) parts.
CLASSIFICATION OF MAGNETIC SEPARATORIt can be classified according to the medium in whichthe separation is made, the mode of the presentationof the feed, the mode of disposal of the products, &whether the magnets are stationary or moving.
IMPORTANT TYPES OF MAGNETIC SEPARATOR1. EDISON SEPARATOR2. BALL NORTON SEPARATOR3. MAGNETIC DRUM SEPARATOR4. ROLLAR TYPE SEPATOR5. GRAVITY FEED MAGNETIC SEPARATOR6. MAGNETIC COOLENT SEPARATOR7. WET DRUM SEPRATOR
EDISON SEPARATOREdison separator consists of a barmagnet . The ore as thin streams fallsin front of the poles, susceptibleparticles being deflected inwards &nonsusceptible particles continuingto fall undeflected.This separator was not whollysuccessful because of inability ofcontrol flow of solid in a thinsheet, & because of lack of controlover the speed of the fallingparticles.
Magnetic drum separators are importantmagnetic separators that removes ferrous metalfrom dry bulk products in free-flowingprocessing systems. They are self cleaning unitconsisting of drums and housing normally ofstainless steel. The magnets used by themagnetic drum separators are either ceramicmagnets or rare earth magnets. The magneticdrum separators are available both in single ordouble drum configuration.
How it Works?The processing materials enters the top of the magneticdrum separator and flows across the surface of the drum.The rotatory drum in the magnetic field captures theferrous tramps whereas non ferrous falls free from thedrum into the cleaned material flow. As the drumrotates, the ferrous metal so captured is carried past thediverter and released outside of the magnetic field.TypesMagnetic drum separators are of different types like:•Electro drum separators•Wet drum separatorsDouble drum separators
ApplicationsThe magnetic drum separator is ideal for separating iron particles fromgranules & 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 productionMetal powder production
Ball Norton SeparatorUnlike most magnetic separators which are used to remove relativelysmall amounts of metal, the Ball Norton Separator is designed tohandle large amounts of ferrous material - removing otherundesirable elements. A unique combination of alternatingmagnetic poles and vibratory conveying works to clean the magneticmaterial. Applications include foundry shot, crushed borings, slagand magnetic ores.
How it Works?The material is discharge on the belt by the feeder. The magnetic rollis enveloped by the conveyor. The para and ferro magneticingredients remains stuck to the belt whereas non magneticingredients passes freely at the end of the conveyor.Roller type magnetic separator ismeant to separate ferrous contaminantsfrom the flimsy magnetized drygranular metallic and nonmetallicmaterials. Roller type magneticseparator has wide application inindustries and mineral technology. Theseparator uses high powered rare earthmagnets with very low dimensionaltolerance. The other components of themachine are conveyor and vibratoryfeeder. The magnetic rolls are availablein different widths and magneticstrength
ApplicationsRoller type magnetic separator finds applications in the following areaslike:•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 metalthrough gravity system. These magnets are constructedout of welded stainless steel and are available in stainlesssteel structure. The gravity magnet comes in differentshapes and sizes and are ideal for narrow chuteapplications. Gravity feed magnets are normally used invertical flow system.
ApplicationsGravity magnetic separators have different industrial and commercialusage. They are applied in industries like:•Food industry•Chemical industry•Grain processing industriesPharmaceutical industries
MAGNETIC COOLENT SEPARATORMagnetic coolant separator is adevice which cleans the coolantliquid of very fine ferrous particles.It removes the iron chips from themilling or grinding liquid. It is lightand compact structure havingstrong magnetic power which canremove very fine ferrous particles.For precise grinding operationsuninterrupted flow of oil is must.The coolant magnetic separatorensures the uninterrupted flow ofthe liquid.
Features Wet drum magnets have high magnetic recovery anddischarge. The feed slurries recover the magnetics. Available in single or multiple drum applications. Recover magnetic solids in as clean a magneticconcentrate as possible . Permanent magnet assembly eliminates coil burn-outs . The magnet / pole elements are bolted to a mild steelshaft. The drum is made from thick stainless steel for longservice life. Wet drum separators are available in differentconfiguration like single drum,double drum and multipledrum. In double drum two separators are arranged backto back with a common feed back.
Applications Glass industry Chemical industry Plastic industry Mining industry Food industry Pharmaceuticals industry Foundry industry