On the Characteristics of a Uniflow Type Classifier (4th Report)

Abstract

It is very difficult to separate the powder particles into two classes, the coarse and the fine, when the particles are fine and have a narrow range of size distribution, as they offer a strong cohesion and agglomomeration property. In order to raise the efficiency of the classifier, it is better to send the fine particles to classifier in a state of mono particles. For this purpose we set a dispersion chamber on this side of the classifier, and in the chamber the powders are blown off with a compressed air jet from a nozzle, striking against a collision plate. Then the powders will be dispersed, and a primary classification of the particles can be effected by the drop of velocity and the sudden change of direction of the air flow. In this study, the classifying characteristic of our classifier having a center core along the center axis of classifying chamber was compared with that of an ordinary type cyclone used as a classifier. As a typical material, we used the powdered particles of MgCO₃ having a range of particle size distribution of 1∼23 μ and taking the classifying point at 8 μ.