An Experimental Study of Swirling Flow Pneumatic Conveying System in a Vertical Pipeline

Abstract

A swirling flow is adopted for a vertical pneumatic conveying system to reduce conveying velocity, pipe wear, and particle degradation. An experimental study has addressed the characteristics of swirling flow pneumatic conveying (SFPC) for the total pressure drop, solid flow patterns, power consumption, and additional pressure drop. Polystyrene, polyethylene, and polyvinyl particles with mean diameters of 1.7, 3.1, and 4.3 mm, respectively, were transported as test particles in a vertical pipeline 12.2 m in height with an inside diameter of 80 mm. The initial swirl number was varied from 0.38 to 0.94, the mean air velocity was varied from 9 to 23 m/s, and the mass flow rate of the solids was varied from 0.3 to 1.25 kg/s. The minimum and critical air velocities decreased as much as 20 and 13 percent, respectively, when using SFPC. The total pressure drop and power consumption of SFPC are close to those of axial flow pneumatic conveying in the low air velocity range.