Abstract
The separation performance of zigzag air classifier with angle of 90 degrees was studied using narrow size fractions of thin square samples and granular samples. The simulation results of air velocity inside the classifier indicated that the zigzag geometry induces a flow pattern consisting of an upward flow and a circulation flow. Experimental results showed that float product recovery was described as an integral calculus of normal distribution as a function of dimensionless air velocity (VA/VA50), where VA is superficial air velocity and VA50 is the VA at the fifty percent recovery. The VA values were predicted using the equations derived theoretically from dynamics for a particle dropping in air and derived experimentally. Newtons efficiencies of coal-quartz mixture and coal-pyrite mixture were estimated based on the recovery calculated using the above relations and coincided with the experimental results.
