Experimental Research On Cyclone Performance At High Temperature And Dust Concentration

In order to predict the influence of operating temperatures and concentration on cyclone performance, an experimental investigation was conducted on particle separation in a reverse flow, tangential volute-inlet cyclone separator, which had a diameter of 300 millimeters, with air heated up to 673K. The test powder silica had a mass median diameter of ca. 16 microns and the test powder talcum had a mass median diameter of ca. 16 microns. The inlet concentration ranged from 2g/m3~60g/m3. Both the separation efficiency and pressure drop of the cyclone were measured as a function of the inlet velocity and operating temperature. Firstly, for silica powder, the separation efficiency decreased with the increase of concentration; but for talc powder, the separation efficiency increased with the rise of concentration. Secondly, the fractional efficiency exhibited the same trend as the separation efficiency when the dust concentration changed. Thirdly, for both test powders, an increase of dust concentration all resulted in a lower pressure drop though not to the same extent.. Forthly, as the temperature rised, the separation efficiency became higher for talc powder but lower for silica powder. Finally, With the increase in temperature, the pressure drop of a cyclone tended to fall with other conditions remained unchanged. It seemed that the physical property of the test powder had little influence on the cyclone pressure drop.An analysis of our own data and published results showed that the fractional efficiency of a cyclone was a definite function of such dimensionless numbers as Stokes number, Reynolds number, Froude number and dimensionless cyclone inlet area and dimensionless outlet diameter. A non-dimensional experimental correlation of the cyclone performance, including the influence of temperature, was obtained on the basis of previous work. The prediction of the influence of temperature on separation efficiencies and pressure drops was in fairly good agreement with experimental results.