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Magnetic Seperation
This document discusses various methods for separating mixtures, with a focus on magnetic separation. It provides an overview of different types of magnetic separators and how they work. The key methods mentioned include using magnetism to separate magnetically susceptible materials, concentrating ores containing iron or other magnetic minerals, and separating slightly paramagnetic minerals. The document also classified magnetic separators based on their magnetic source, field strength, materials, field type, body shape and other characteristics.
Magnetic Seperation
- 6. What are thedifferent ways of separating mixtures? • Magnetism • Hand separation • Filtration • Sifting or sieving • Extraction and evaporation • Chromatography
- 7. Adsorption, adhesion ofatoms, ions or molecules of gas, liquid, or dissolved solids to a surface Centrifugation and cyclonic separation, separates based on density differences Chromatography separates dissolved substances by different interaction with (i.e., travel through) a material Crystallization Decantation Demister (vapor), removes liquid droplets from gas streams Distillation, used for mixtures of liquids with different boiling points Drying, removes liquid from a solid by vaporisation Electrophoresis, separates organic molecules based on their different interaction with a gel under an electric potential (i.e., different travel)
- 8. Elutriation Extraction Leaching Liquid-liquid extraction Solid phaseextraction Flotation Dissolved air flotation, removes suspended solids non- selectively from slurry by bubbles that are generated by air coming out of solution Froth flotation, recovers valuable, hydrophobic solids by attachment to air bubbles generated by mechanical agitation of an air-slurry mixture, which float, and are recovered Deinking, separating hydrophobic ink particles from hydrophilic paper pulp in paper recycling
- 9. Flocculation, separates asolid from a liquid in a colloid, by use of a flocculant, which promotes the solid clumping into flocs Filtration, Mesh, bag and paper filters are used to remove large particulates suspended in fluids (e.g., fly ash) while membrane processes including microfiltration, ultrafiltration, nanofiltration, reverse osmosis, dialysis (biochemistry) utilising synthetic membranes, separates micrometre-sized or smaller species Fractional distillation Fractional freezing Oil-water separation, gravimetrically separates suspended oil droplets from waste water in oil refineries, petrochemical and chemical plants, natural gas processing plants and similar industries Magnetic separation Precipitation Recrystallization Sedimentation, separates using vocal density pressure differences Gravity separation Sieving Stripping Sublimation Vapor-liquid separation, separates by gravity, based on the Souders-Brown equation Winnowing Zone refining
- 11. INTRODUCTION # Magnetic separationis 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.
- 12. INTRODUCTION # By combiningthe 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.
- 16. APPLICATIONOF MAGNETISMAS SEPARATOR BasicallyMagnetism 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.
- 17. 4. For theremoval 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.
- 18. magnetic source • permanent magneticseparator • electromagnetic separator strength of magnetic field • Weak magnetic separator • Middle magnetic separator • Strong magnetic separator materials • wet type magnetic separator • dry type magnetic separator type of magnetic field • constant • pulsating • alternating body shape • belt-type magnetic separator • drum-type magnetic separator • roll-type magnetic separator • disc-type magnetic separator • ring-type magnetic separator • cage-type magnetic separator • pulley-type magnetic separator Classification of Magnetic seperators
- 19. S S S N NN Magnetic Feed N S Nonmagnetic dry separation drum separator Feed Magnetic permanentmagnets Nonmagnetic Wet separatior
- 20. Magnetic separation Magnetic N Nonmagnetic Feed S Semiproduct Drum witheasy and difficult to magnetise discs (IIIIII) Induction type separator
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- 24. Feed N S Cycle I Filling Water CycleII Magnetic particles Magnetic particles Nonmagnetic particles HGMS, peridical
- 27. HGMS, continueous Feed Feed Nonmagnetic Washing off semiproduct Separating compartment Washingoff magnetic particles Magnet coil Magnet yoke
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Editor's Notes
- #20 1, according to the magnetic source, the magnetic separator can be divided to permanent magnetic separator and electromagnetic separator. 2, according to the strength of magnetic field, it can be divided into: (1) Weak magnetic separator, the surface magnetic strength HO=72-136 KA/m, magnetic force HgradH= (2.5-5.0) 1011 A/m. (2) Middle magnetic separator, the surface magnetic strength HO=160-480 KA/m; (3) Strong magnetic separator, the surface magnetic strength HO=480-1600 KA/m, magnetic force HgradH= (1.5-6.0) 1013 A/m. 3, according to the materials, it can be divided to wet type magnetic separator and dry type magnetic separator; 4, according to the type of magnetic field, it can be divided into constant, pulsating and alternating magnetic separator; 5, according to the body shape, it can be divided into belt-type magnetic separator, drum-type magnetic separator, roll-type magnetic separator, disc-type magnetic separator, ring-type magnetic separator, cage-type magnetic separator and pulley-type magnetic separator. In the past, the electromagnetic separator had widely used in the industrial; the body shape mainly was drum or belt type. Now, the commonly used separators are wet type and permanent magnetic separators. The weak magnetic separator is mainly used to process the ferromagnetic minerals such as magnetite, titanium magnetite and ferrosilicon. The middle magnetic separator was mainly used to process the partial oxidation and strong magnetic minerals. In the past, the strong magnetic separator was mainly used to process the coarse minerals. The dry-type strong magnetic separator was used to process the non-ferrous minerals or rare metal minerals. In the recent years, we have developed various forms of wet-type magnetic separator to process the low grade, complex composition and weak magnetic minerals, for example ring-type strong magnetic separator, cage-type and disc-type strong magnetic separator.