Gear pelleter

Figure 12.10. Equipment for compacting, briquetting, and pelleting, (a) Flowsketch of a process for compacting fine powders, then granulating the mass (Allis-Chahners Co.), (b) Integrated equipment for roll compacting and granulating (Fitzpatrick Co.), (c) A type of briquetting rolls, (d) A gear pelleter. (e) A double roll extruder.

A wide variety of extruders are available on the market, including basket extruders, screw extruders, gear pelletizers, and... 

Figure 89 depicts sketches of typical pelleting machines.With the exception of the first method (a), which applies a flat die, all other machines feature cylindrical dies and operate in a very similar manner as roller presses. The general principle is modified such that the material is pulled into the nip but then is extruded through bores in the dies and often scraped off with a knife . Equipment types (b) and (d) represent directly the modified roller press principle. Machine type (c) uses a press roller located within the cylindrical die and therefore resembles ring roll presses (see Section 4.2.2.4.4). To improve the grip and increase densification force gear pelleters (e) are applied which are said to produce pellets of superior quality. 

Figure 89. Schematic representation of different pelleting machines, (a) Flat die and edge rollers, (b) two hollow cylindrical dies, (c) one hollow cylindrical die with internal solid press roller, (d) one hollow cylindrical die with external solid press roller, (e) gear pelleter...

Figure 324. Photograph of a gear pelleter . (Courtesy of Bepex/Hutt, Leingarten, FRG)...

In pressure agglomeration, the distance between the surfaces of compacting tool sets specifically in extrusion, the distance between the pressure generating device and the die plate, in roller presses, the closest distance between the rollers. Double-roll pellet mill in which the rollers are in the shape of coarse, intermeshing gears with bores at the root sections between the gear teeth. (Also gear pelletizer.) Distribution plate in which the perforations are manufactured such that they produce a directional flow of gas. See melt solidification. 

Usually rotating pan, drum, cone, or the like for growth a lomeration. (See also gear pelletizer .)... 

In medium-pressure agglomeration equipment (Fig. 8.42), the perforated support (die) can be either flat (a), concave (b), or convex (c). For all three designs, intermeshing, toothed executions have been proposed in the patent literature [B.42] to avoid slippage and improve extrusion as well as extrudate quality, but only the so called gear pelleter , in which the convex dies (Fig. 8.42c) are hollow gears with extrusion channels between the teeth, has reached commercial importance (see below). 

Fig. 8.66 Schematic representation of the operating principle of a "gear pelletizer" (courtesy Hosokawa Bepex/HUTT. Leingarten. Germany).

Double-roll PELLET MILL in which the ROLLERS are in the shape of coarse, intermeshing gears with bores at the root sections between the gear teeth. (Also gear PELLETIZER)... 

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