Humphreys spiral concentration

Principle of Operation Spiral concentration of ores and industrial materials is based primarily on the specific-gravity differentials of the materials to be separated. The shape facdor of the feed material is also important, and utilization of reagentized feed can change the apparent specific gravity of component minerals by forced attachment of air bubbles to mineral floes. The best known spiral-type concentrator is the Humphreys spiral concentrator, which first proved its commercial feasibihty in 1943. In that year an Oregon plant successfully... 

The Humphreys spiral concentrator is a spirally shaped channel or launder with a modified semicircular cross section, as illustrated in Fig. 19-30. The standard spiral consists of five complete turns, but three-turn units are used in some instances when an unusually rapid and clean separation takes place, as in second-stage or cleaner spirals. There is a drop of 0.34 m (13.5 in)/turn as the flowing pulp progresses from the top to the bottom of the spiral. One spiral concentrator occupies about 0.37 m" (4 ft") of floor space and about 2.1 m (7 ft) of headroom measured from feed to discharge box. The optimum particle-size range of feed particles for spirals is about 10 to 200 mesh (2 to 0.074 mm). 

Gravimetric separation systems. These include jigs, shaking tables, Humphrey-type spiral concentrators, and so on. 

Humphrey s spiral gravity flow concentrator, 16 632 100% product philosophy,... 

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