Conveying mechanism

The product, after filtration, is conveyed mechanically to another filter on which the cyclonite is washed with cold water until deacidification is as complete as pos-... 

L. Frye, W. Peukert, Attrition of bulk solids in pneumatic conveying mechanisms and material properties, Part. Sci. Technol. 20 (2002) 267-282. 

The previously described solids conveying mechanism represents, in essence, the conveying of solids in SSEs, although a realistic conveying model for the latter is somewhat more complicated because, as Chapter 9 explains, the channel is curved. 

Drag-induced flow in a rectangular channel, as in Fig. 4.15, neglecting cross-channel forces, resulted in Eq. 4.9-3. We now consider the effect of these forces on the conveying mechanism. 

An excellent historical review and applications of this type of extruder were produced by White (53), and the flow was modeled by Janssen et al. (62) and Wyman (63), whose derivation we follow. The easiest way to visualize the conveying mechanism of a counterrotating intermeshing TSE is to place a robot viewer into the screw channel at point 0 in Fig. 6.37(d) and let it report its observations. We first stop the rotation of the screws and tell our viewer to explore the space around it. It will report that the space is entirely confined by steel walls the barrel surface from above, the flights of screw A at either side, and the intermeshing flight of screw B both up-channel and down-channel. The space is a helically distorted C-shaped channel that can be shown schematically, as in Fig. 6.46, or by molding silicone rubber into the space in Fig. 6.47. Clearly, by fully... 

The Melting Zone As we pointed out earlier, from the axial location where a melt film is formed at the barrel surface (either as a result of barrel heating or as a result of heat generation due to friction), to the axial location where a melt pool appears at the pushing flight, lies the delay zone. The conveying mechanism in this zone is one of viscous drag at the barrel surface, determined by the shear stresses in the melt film and,... 

Consideration must also be given to ancillary requirements that will be necessary to support the milling process. Such equipment could include cooling systems, dust collectors. special electrics and conveying mechanisms which will affect capital requirements and day to day operating costs. Dust-free manufacturing capability is a very important requirement in current industry standards. 

Continuous tunnels are batch truck or tray compartments, operated in series. The solids to be processed are placed in trays or on trucks which move progressively through the tunnel in contact with hot gases. Operation is semicontinuous when the tunnel is filled, one truck is removed from the discharge end as each new truck is fed into the inlet end. In some cases, the trucks move on tracks or mono-rails, and they are usually conveyed mechanically, employing chain drives connecting to the bottom of each truck. 

Fig. 2 Comparison of twin-screw conveying mechanisms. (Courtesy of Coperion Corporation.) (View this art in color at WWW. dekker. com.)...

Continuous conveyor, through-circulation, or impinging jet-fluidized bed dryers (sometimes called jet-zone dryers) are often used in the wood processing (e.g., wafer board) and food processing (e.g., potato chips, etc.) industries. In the jet-zone process, hot air jets impinge on a thin layer of wet chips, which are conveyed mechanically the high-velocity jets pseudo-fluidize the material to accomplish uniform drying. Wood chips, for example, may be dried in a rotary or a conveyor dryer. 

Material conveying mechanism Flow stability (surging) Pressure generation Venting capability Feeding capability Molten flow pattern in 8-figure cross-section... 

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