Spiral concentrators are devices to separate solid components in a slurry, based upon a combination of the solid particle density as well as the particles hydrodynamic properties (e.g. drag). The device consists of a tower, around which is wound a sluice, from which slots or channels are placed in the base of the sluice to extract solid particles that have come out of suspension.
As larger and heavier particles sink to the bottom of the sluice faster and experience more drag from the bottom, they travel slower, and so move towards the center of the spiral. Conversely, light particles stay towards the outside of the spiral, with the water, and quickly reach the bottom. At the bottom, a cut is made with a set of adjustable bars, channels, or slots, separating the low and high density parts. Many things can be done to improve the separation efficiency, including: -changing the rate of material feed -changing the grain size of the material -changing the slurry mass percentage -adjusting the cutter bar positions -running the output of one spiral separator (often, a third, intermediate, cut) through a second. -adding wash water inlets along the length of the spiral, to aid in separating light minerals -adding multiple outlets along the length, to improve the ability of the spiral to remove heavy contaminants -adding ridges on the sluice at an angle to the direction of flow.
Typical spiral concentrators will use a slurry from about 20%-40% solids by weight, with a particle size somewhere between 1.5-.075 mm (17-340 mesh), though somewhat larger particle sizes are sometimes used. For good separation, the density difference between the heavy minerals and the light minerals in the feedstock should be at least 1 g/cm3; and because the separation is dependent upon size and density, spiral separators are most effective at purifying ore if its particles are of uniform size and shape. A spiral separator may process a couple tons per hour of ore, per flight, and multiple flights may be stacked in the same space as one, to improve capacity.
The early hematite beneficiation is mainly gravity separation with machines of jigger, centrifugal separator, spiral chute, spiral washer, shaking table can be involved and later floatation separation has been used in the hematite iron ore upgrading
The early hematite beneficiation is mainly gravity separation with machines of jigger, centrifugal separator,spiral chute, spiral washer, shaking table can be involved and later floatation separation has been used in the hematite iron ore upgrading with floatation separator and magnetic separator involved. However, these single separation methods can not help to get ideal beneficiation efficiency. In recently decades, combination of magnetic separation and gravity separation, magnetic separation andfloatation separation, gravity separation and floatation separation has been adopted to get high grade hematite iron concentrate.
Hematite is main mineral form of iron oxide and main ore mineral of iron.Hematite coexists with magnetite which can be transformed to hematite by oxidation and remain form of hematite forming the illusion of hematite. Hematite separation process is suitable for complex structure hematite such as hematite and impurities with uneven distribution of particle size, ore with large content of fine particle, ore with small amount of magnetite and the gangue minerals containing quartz or kaolin.The beneficiation process includes stage grinding, coarse-fine particle separation, heavy - Magnetic - anionic reverse flotation process.
1.Hematite ore crushing:in this stage there are also three steps, the hematite ore may go through primary crushing, secondary crushing and fine crushing. Hematite primary crushing equipment includes gyratory crusher, jaw crusher, hammer crusher etc. Hematite secondary and fine crushing plants mainly include cone crusher, ball mill, vertical mill, ultrafine mill etc.
2.Main operation steps in the whole hematite beneficiation process includesorting, gravity separation, floatation, magnetic separation, electrostatic separation, chemical mineral processing etc. There are many plants involves in hematite beneficiation process, such as flotation equipment, magnetic separator, electrostatic separator etc.
Closed circuit grinding consisted of ball mill and cyclone is adopted in the first grinding. This ensures the separation efficiency, particle size and part of qualified concentrate, and it also abandons part of low grade tailings which reduce the grinding volume of medium ore and the loss of metal.
Strong magnetic process recycles fine iron minerals, which can play a dual role of de-sliming and tailings out creating good conditions for flotation. Reverse flotation process system is simple, which can significantly reduce the flotation reagents into pulp and decrease the adverse effect on the flotation process.
Titanium is a chemical element with the symbol Ti and atomic number 22. It is a lustrous transition metal with a silver color, low density, and high strength. Titanium is resistant to corrosion in sea water, aqua regia, and chlorine.
Titanium is the ninth-most abundant element in Earths crust (0.63% by mass) and the seventh-most abundant metal. It is present as oxides in most igneous rocks, in sediments derived from them, in living things, and natural bodies of water. Of the 801 types of igneous rocks analyzed by the United States Geological Survey, 784 contained titanium. Its proportion of soils is approximately 0.5 to 1.5%.
Common titanium-containing minerals are anatase, brookite, ilmenite, perovskite, rutile, and titanite (sphene). Akaogiite is an extremely rare mineral consisting of titanium dioxide. Of these minerals, only rutile and ilmenite have economic importance, yet even they are difficult to find in high concentrations. About 6.0 and 0.7 million tonnes of those minerals were mined in 2011, respectively. Significant titanium-bearing ilmenite deposits exist in western Australia, Canada, China, India, Mozambique, New Zealand, Norway, Sierra Leone, South Africa, and Ukraine. About 186,000 tonnes of titanium metal sponge were produced in 2011, mostly in China (60,000 t), Japan (56,000 t), Russia (40,000 t), United States (32,000 t) and Kazakhstan (20,700 t). Total reserves of titanium are estimated to exceed 600 million tonnes.
Titanium can be alloyed with iron, aluminum, vanadium, and molybdenum, among other elements, to produce strong, lightweight alloys for aerospace (jet engines, missiles, and spacecraft), military, industrial processes (chemicals and petrochemicals, desalination plants, pulp, and paper), automotive, agriculture (farming), medical prostheses, orthopedic implants, dental and endodontic instruments and files, dental implants, sporting goods, jewelry, mobile phones, and other applications.