Rotating-shell mixers

Industrial equipment. Rotating-shell mixers or tumbling mixers are shown in Fig. 3. Drum-type, cubical-shaped, double-cone, and twin-shell blenders with their axis of rotation horizontal to the center of the drum on its axis increase crossflow and improve the mixing action. Cubical and polyhedron-shaped... 

Stationaiy. shell or trough. There are a number of different types of mixers in which the container is stationary and material displacement is accomplished by single or multiple rotating inner mixing devices. 

Figure 10.15. Some mixers and blenders for powders and pastes, (a) Ribbon blender for powders, (b) Flow pattern in a double cone blender rotating on a horizontal axis, (c) Twin shell (Vee-type) agglomerate breaking and liquid injection are shown on the broken line, (d) Twin rotor available with jacket and hollow screws for heat transfer, (e) Batch muller. (f) Twin mullers operated continuously, (g) Double-arm mixer and kneader (Baker-Perkins Inc.), (h) Some types of blades for the double-arm kneader (Baker—Perkins Irtc.).

Entrop [63] reported the process characteristics of the Nauta mixer. The Nauta mixer utilizes an orbiting action of a helical screw rotating on its own axis to carry material upward, while revolving about the centerline of the cone-shaped shell near the wall for top-to-bottom circulation., see the sketch in Fig. 37. Nauta mixers of different sizes are not build geometrically similar to each other The diameter of the helical screw and its pitch are kept equal. 

Fig. 32. Diagrammatic outlines of powder mixers (Al). A, horizontal rotating cylinder B, cylinder—off center axis of rotation C, similar to B but hexagonal shape D, rotating cube E,G, double cone F, pyramid H, twin shell I,J, Y cone.

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