Conveyor-bowl centrifuge

The Imperforate Bowl Centrifuge. In an imperforate bowl centrifuge the dow of the continuous Hquid phase is nominally axial, except for areas immediately adjacent to the feed inlet and efduent oudet. Tubular soHd-bowl basket and imperforate bowl conveyor-discharge centrifuges satisfy this definition. 

Excessive volume of soHds may be retained in the bowl of conveyor centrifuges if (/) the conveyor volumetric displacement is not sufficient to handle the sedimentation rate of soHds (2) the sedimented soHds cannot be successfully conveyed and discharged over the soHds port until a sufficient layer has been built up inside the bowl and (3) soHds do not easily sHde outwardly on the underside of the disk of a disk centrifuge. 

Fig. 16. An imperforate bowl conveyor-discharge centrifuge, where 1 corresponds to feed suspension 2, to hquid phase 3, to sohd phase 4, to hquid pool ...

Effect of Fluid Viscosity and Inertia The dynamic effect of viscosity on a rotating liquid slurry as found in a sedimenting centrifuge is confined in veiy thin fluid layers, known as Ekman layers. These layers are adjacent to rotating surfaces which are perpendicular to the axis of rotation, such as bowl heads, flanges, and conveyor blades, etc. The thickness of the Ekman layer 6 is of the order... 

Power generates bigb settling forces. Slurry centrifuged against rotating bowl, and removed by slower rotating helical screw conveyor within bowl. 

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