Jig concentrators
Encyclopedia
Jig concentrators are devices used mainly in the mining industry for mineral processing
, to separate particles within the ore body, based on their specific gravity
(relative density
). The particles would usually be of a similar size, often crushed and screened prior to being fed over the jig bed. There are many variations in design, however the basic principles are constant: The particles are introduced to the jig bed (usually a screen) where they are thrust upward by a pulsing water column or body, resulting in the particles being suspended within the water. As the pulse dissipates, the water level returns to its lower starting position and the particles once again settle on the jig bed. As the particles are exposed to gravitational energy
whilst in suspension within the water, those with a higher specific gravity (density) settle faster than those with a lower count, resulting in a concentration of material with higher density at the bottom, on the jig bed. The particles are now concentrated according to density and can be extracted from the jig bed separately. In the mining of most heavy minerals, the denser material would be the desired mineral and the rest would be discarded as floats (or tailings
). There are some minerals, notably coal
, that are lighter (lower in density) than the surrounding rock and in such instances the process of extraction would work in reverse, i.e. the coal would settle on top with the rock below (on the jig bed). There are several designs and methods of extraction from the jig bed.
Mineral processing
In the field of extractive metallurgy, mineral processing, also known as mineral dressing or ore dressing, is the process of separating commercially valuable minerals from their ores.-History:...
, to separate particles within the ore body, based on their specific gravity
Specific gravity
Specific gravity is the ratio of the density of a substance to the density of a reference substance. Apparent specific gravity is the ratio of the weight of a volume of the substance to the weight of an equal volume of the reference substance. The reference substance is nearly always water for...
(relative density
Relative density
Relative density, or specific gravity, is the ratio of the density of a substance to the density of a given reference material. Specific gravity usually means relative density with respect to water...
). The particles would usually be of a similar size, often crushed and screened prior to being fed over the jig bed. There are many variations in design, however the basic principles are constant: The particles are introduced to the jig bed (usually a screen) where they are thrust upward by a pulsing water column or body, resulting in the particles being suspended within the water. As the pulse dissipates, the water level returns to its lower starting position and the particles once again settle on the jig bed. As the particles are exposed to gravitational energy
Gravitational energy
Gravitational energy is the energy associated with the gravitational field. This phrase is found frequently in scientific writings about quasars and other active galaxies.-Newtonian mechanics:...
whilst in suspension within the water, those with a higher specific gravity (density) settle faster than those with a lower count, resulting in a concentration of material with higher density at the bottom, on the jig bed. The particles are now concentrated according to density and can be extracted from the jig bed separately. In the mining of most heavy minerals, the denser material would be the desired mineral and the rest would be discarded as floats (or tailings
Tailings
Tailings, also called mine dumps, slimes, tails, leach residue, or slickens, are the materials left over after the process of separating the valuable fraction from the uneconomic fraction of an ore...
). There are some minerals, notably coal
Coal
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...
, that are lighter (lower in density) than the surrounding rock and in such instances the process of extraction would work in reverse, i.e. the coal would settle on top with the rock below (on the jig bed). There are several designs and methods of extraction from the jig bed.