The bowl classifier incorporates a two-stage baffled-return separating action, and it consists of a straight classifier with the usual reciprocating rakes, upon which is superimposed at the lower end a shallow circular bowl with a revolving rake mechanism. The general construction of the Dorr Bowl Classifier is shown in Fig. 20.
The feed enters at the centre of the bowl, and, falling on to a baffle-plate placed at the level of the surface of the pulp, is directed radially outwards. In passing from the centre to the periphery the coarser particles settle and only the fines overflow into the annular