Classification with Streams of Air or Water

Hickson (1992) defined classification as a means for sorting out of particles to achieve a desired degree of uniformity. The term separation usually refers to dissimilar materials, whereas classification applies to different grades or sizes of the same material. These definitions will apply in this section. 

Particle characteristics affect classification. The particles should be 

As the name implies, air classifiers operate on the basis of air flow. It is an elutriation process in which the separation occurs using air. Fine particles rise in the air stream and the coarse particles that are too heavy to be carried upward fall under the influence of gravity. The cut point in a classification system can be adjusted by the air velocity within the unit. 

Improved designs enhance the economics of a process to produce finer, better quality products with 

Chemical Engineering Buyers Guide 2004 (2003) lists more than 30 manufacturers of such equipment. 

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