Abstract
Dust separation characteristics of a counter-flow vortex tube were investigated with lime powders whose mean particle sizes were 5 and 14.6µm. The experiment showed that a vortex tube can be used as an efficient pre-skimmer to separate particles from the waste gas in industry. In case of fine particles, a trend of increasing separation efficiency was observed with inlet pressure up to 160kPa at which the flow rate was 9.5m3/hr, but there was a tendency of reduction in the coarse particles. For both powder sizes, the efficiency and the effective nozzle inlet velocity were 93% and 14.52m/s respectively, while the tested vortex tube had a small diameter of 16mm and the ratio of the nozzle hole area to the tube cross-sectional area was 0.15. Additionally, the geometric ratios of the vortex tube could be proposed as 0.44 for the ratio of the orifice diameter at clean gas exit to the tube diameter and 14.0 for the ratio of the tube length to the diameter.
