B04—CENTRIFUGAL APPARATUS OR MACHINES FOR CARRYING-OUT PHYSICAL OR CHEMICAL PROCESSES
B04C—APPARATUS USING FREE VORTEX FLOW, e.g. CYCLONES
B04C5/00—Apparatus in which the axial direction of the vortex is reversed
B04C5/14—Construction of the underflow ducting; Apex constructions; Discharge arrangements ; discharge through sidewall provided with a few slits or perforations
B04C5/18—Construction of the underflow ducting; Apex constructions; Discharge arrangements ; discharge through sidewall provided with a few slits or perforations with auxiliary fluid assisting discharge