The Efficiency Change of Spiral Classifier with Different Overflow Discharge Methods

Abstract

The basic structure, classification principle and low efficiency of the traditional spiral classifier were analyzed. The trial industrial comparative experiment was carried out by using φ300×4500 spiral classifier with the two-sided overflow and the port side overflow at the same parameter. The experimental results showed that, the qualified fine materials could overflow with the shortest distance by using two-sided overflow method, which avoided circulation circuit of fine materials and reduced the content of-200 mesh fine materials in the sinking sand down lower 2-5 percentage points compared with the port side overflow. At the same time, adjusting the overflow emissions height of two-sided overflow could delay the settling time of coarse mineral which reduced the content of +200 mesh materials of the overflow discharge lower 5-8 percentage points than the port side overflow. Compared with the port side overflow, the classification efficiency was improved about from 40% to 60%, and the average increase rate was up to 17%. The improvement of overflow discharge can be used not only for the adjusting of present spiral classifiers but also for making new machines, which is of a significant application prospect.