Classification of Particles in the Submicron Range in an Impeller Wheel Air Classifier

Abstract

It is the aim of this paper to show that it is possible in principle to obtain submicron cut sizes with a counterflow centrifugal classifier, provided that a forced vortex is used in the classification chamber and the circumferential velocities are greater than 100 m/s. These findings can be generalized and are not limited to the geometrical dimensions of the classifier used in the experiments. With a new impeller or deflector wheel classifier, cut sizes as small as 0.3 μm have been obtained with feed mass flow rates of 5 kg/h and higher.