Specific gravity recovery

If antimony and arsenic are present ia the feed, copper and iron react to form the respective antimonides and arsenides known as speiss (specific gravity 6.0). If it is preferred to remove copper ia a speiss layer, the sulfur ia the siater must be reduced and the addition of scrap iron may be necessary to encourage speiss formation. Matte and speiss are usually sent to a copper smelter for recovery of the metals. 

The electrostatic separation method is the exclusive choice in some specific situations, for example in the cases of rutile and ilmenite deposits. These deposits generally contain minerals of similar specific gravities and similar surface properties so that processes such as flotation are unsuitable for concentration. The major application of electrostatic separation is in the processing of beach sands and alluvial deposits containing titanium minerals. Almost all the beach sand plants in the world use electrostatic separation to separate rutile and ilmenite from zircon and monazite. In this context the flowsheet given later (see Figure 2.35 A) may be referred to. Electrostatic separation is also used with regard to a number of other minerals. Some reported commercial separations include those of cassiterite from scheelite, wolframite from quartz, cassiterite from columbite, feldspar from quartz and mica, and diamond from heavy associated minerals. Electrostatic separation is also used in industrial waste recovery. 

The Ferret process actively draws in water, as well as free and dispersed hydrocarbons. The inward pull causes water and product to move toward the Ferret inlet, enhancing recovery. Once the product/water mixture is taken inside the Ferret inlet, separation takes place specific gravity is used to split the hydrocarbons and water into separate pumping paths. 

Fibers (qv) have been defined by the Textile Institute as units of matter characterized by flexibility, fineness, and a high ratio of length to thickness (3). For use in textile applications, fibers should have adequate temperature stability, strength, and extensibility. Other important qualities include cohesiveness or spinability and uniformity. There are also several secondary characteristics that improve customer satisfaction and therefore may be desirable. These include cross-sectional shape, specific gravity or density, moisture regain, resiliency, luster, elastic recovery, and resistance to chemicals, environmental conditions, and biological organisms. 

The increased mining requirement is due to a decrease in clean coal recovery at lower specific gravities of separation. Although the specific gravity of coal is less than its mineral impurities, some coal is lost with the refuse material (mineral matter) as the specific gravity at which the coal is cleaned decreases. The rela-... 

Dense-media cyclones are generally operated in the (0.7—1.0) X lO Pa (10-15-lbf/in ) range. It is not aclvisable to go below (0.4-0.56) X 10 Pa because the recovery of low-specific-gravity material and the rejection of impurity are improved at higher pressures. 

After petroleum recovery and prior to the commencement of refining, there needs to be an estimate of the potential behavior of petroleum during refining operations. Briefly, three frequently specified properties that are used to evaluate petroleum are density (specific gravity, API gravity), characterization factor, and sulfur content (Matar, 1992 Speight, 1999 2000 2001). 

Figure 3. Weight recovery vs. specific gravity for mine-run composites...

Successful development of a commercial-scale solvent-extraction process depends to a large degree on selection of the most appropriate solvent. Important criteria for solvent selection include price, toxicological constraints, availability, solute selectivity, recovery difficulties, physical properties (water solubility, specific gravity, viscosity, boiling point), and operational hazards (flammability, volatility). Final choice would likely be a compromise among these criteria. 

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