The curved vanes of the "Fixed Vane Assembly" rotate the inlet stream at the entrance into the vortex tube. The resulting centrifugal action forces the free liquids to the wall of the tube and along to the circumferential gap. As with the vertical units, the liquids and solids are drawn through the gap together with a portion of the gas stream, into the annulus between the vortex tube and the body shell. The low-pressure core of the vortex creates suction at the gap. This suction of recycle is achieved by means of a single port from the "Fixed Vane Assembly" into the annulus. Liquids, having passed through the gap, drop out due to gravity and drain back to the sump. The recycled gas re-enters the vortex tube and combines with the main stream. The clean gas leaves the system (tube) thoroughly scrubbed and liquid free.

Retrofitting the axial flow vortex tubes to replace vane-pack, wire-mesh, or other deminsters in existing vessels is typically done when an increase in the volume may cause the existing demister not to keep up and be ultimately undersized. This may also be combined with a vortex-tube cluster installed at the inlet.