The Influence of Particle Humidity on Separation Efficiency for an Axial Cyclone Separator

This study aimed at evaluating the influence of particle humidity on separation efficiency for an axial cyclone separator. The collection and grade efficiencies of an axial cyclone separator were measured by on-line method for inlet velocities, particle concentration and particle relative humidity in the ranges of 12-18 m/s, 30-500 mg/m³ and 8-30‰, respectively. The experimental results showed that the volume proportion of the inlet particles with bigger particle diameter increased with the increasing of particle relative humidity, because the liquid bridge forces among particles were strengthened with the increasing of particle relative humidity, which caused to the particles easily aggregates to bigger ones. If the inlet velocity and particle relative humidity were constant, the improvements on collection and grade efficiencies were obviously with the increasing of particle concentration because of particle aggregation. However, if the inlet velocity and particle concentration were constant, the grade efficiencies did not always increased with the increasing of particle relative humidity. Furthermore, the grade efficiency curves for different particle relative humidity crossed at the particle diameter approximately 10μm, the grade efficiency would be moved up with the increasing of particle relative humidity when the particle diameter bigger than 10 μm, and the trends of the curves were contrast when the particle diameter lower than 10 μm. Because the liquid bridges among particle were easy to be broken by centrifugal force, the higher the particle relative humidity got, the more fine particles escaped from the cyclone separator outlet.