Effects of gas leakage from the dipleg on the pressure characteristics in a cyclone separator

Abstract

AbstractGas leakage from the dipleg of a cyclone separator usually exists due to the the inlet and dipleg output being in a common space. To gain further insight into the pressure characteristics produced by such gas leakage, the pressure drops and instantaneous pressures in a cyclone separator were measured by a U‐tube and dynamic pressure sensors, respectively, under the conditions of different inlet velocities and gas leakage rates. The results showed that the pressure drop linearly decreased with increased gas leakage rate. And the instantaneous pressure fluctuation amplitudes of some regions were greatly affected by gas leakage variations. Instantaneous pressure data were processed in terms of SD, which revealed that the oscillation of the vortex core caused the pressure fluctuations. When the pressure of the upward gas leakage was equal to that of the axial wall surface, the end of the vortex core attached to the lateral wall and formed the larger pressure fluctuation. A power spectral density analysis was carried out for pressure time‐series data, and then the swing frequency (180 Hz) of the vortex core end was detected on the cyclone separator wall surface in the cone lower region (tapping 4). As a consequence, gas leakage could lead to separated particles being re‐entrained, which might heavily deteriorate separation performance of the cyclone separator.