Experimental investigation on flow splitting for the elimination of localized secondary flow in cyclones and enhancement of their performance

Abstract

The limitation of cyclone performance is attributed to the presence of localized secondary flow, including longitudinal circulation, short circuit flow and eccentric circulation. The present study proposes an enhanced cyclone with split flow (ECSF) to effectively suppress the local secondary flow in cyclones. An experimental setup was constructed to evaluate the performance of ECSF under various operating conditions. The results of the experiment demonstrate that the separation efficiency of ECSF surpasses that of Lapple cyclone due to the synergistic effect of split flows in both the by-pass flow and underflow. When the feed velocity is 13 m/s, the ECSF exhibits a reduced separation efficiency of 89.8% for 10 μm silica particles, which surpasses that of the Lapple cyclone by 10.6%. The ECSF achieves its maximum total and reduced separation efficiencies at a feed velocity of 27 m/s, reaching values of 96.3% and 95.7%, respectively. Compared to the Lapple cyclone, the ECSF demonstrates an extended range of operational capabilities with respect to feed velocity. By maintaining a constant total split ratio in ECSF while increasing the proportion of by-pass flow, it is possible to improve its separation efficiency without augmenting overall energy consumption. The findings of this investigation offer valuable insights for enhancing the dust removal efficiency of cyclones.