Hydroseparators and sizers classifiers

Classifiers that depend on the difference in the settling rates of different size particles in water are frequently used for separating fine particles, in the 50 to 300 /im range. Various designs are used. The principal ones used in the chemical process industries are described below. 

Thickeners, thickeners are primarily used for liquid-solid separation (see Section 10.4). When used for classification, the feed rate is such that the overflow rate is greater than the settling rate of the slurry, and the finer particles remain in the overflow stream. 

Bowl classifiers are shallow bowls with concave bottoms, fitted with rakes. Their operation is similar to that of thickeners. 

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