Solid/liquid separation equipments classifiers

Solid-liquid separation equipment can also be classified according to principle of each unit operation. A list of equipment based on operating principle is given as follows and will be discussed. 

Industrial separators nearly all provide for the continuous removal of settled solids. The separation may be partial or very nearly complete. A settler that removes virtually all the particles from a liquid is known as a clarifier, whereas a device that separates the solids into two fractions is called a classifier. The same principles of sedimentation apply to both kinds of equipment. 

Preliminary Selections Assembling background information permits tentative selection of promising equipment and rules out clearly unsuitable types. If the material to be processed is a slurry or pumpable suspension of sohds in a liquid, several methods of mechanical separation m be suitable, and these are classified into settling and filtration methods as shown in Fig. 18-196. If the material is a wet solid, removal of hquid by various methods of expression should be considered. 

Setthng does not give a complete separation one product is a concentrated suspension and the other is a liquid which may contain fine particles of suspended solids. However, settling is often the best way to process very large volumes of a dilute suspension and remove most of the liquid. The concentrated suspension can then be filtered with smaller equipment than would be needed to filter the original dilute suspension, and the cloudy liquid can be clarified if necessary. Settlers can also be used for classifying particles by size or density, which is usually not possible with filtration. 

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