The gas flow field and the fractional efficiency of a novel combined system of circulation pre stripper & vortex quick separator (CVQS) were investigated via a large-scale cold model. The results showed that the separation efficiency of particles under 7 μm almost unchanged with increasing ejection gas speed

while getting smaller when the particle size was between 7 μm to 20 μm

and higher as the particle size is beyond 20 μm. On the basis of above investigations

the gas-solid separation mechanism of CVQS was talked over

and a triple region model used for analyzing the fractional efficiency of CVQS was proposed. The calculated results showed that this model was in good agreement with experimental data within the larger particle size distribution (beyond 20 μm) and the maximum relative deviation was under 6.1%. For the particle under 20 μm

there was an obvious difference between experimental and model values

whose relative deviation was within 45.7% and 80.5%

respectively. Therefore

the triple region model had important reference value in CVQS engineering design for separating particles beyond 20 μm.