Mixer pug mills

B.2 Mixers with horizontal movement (ribbon mixers, pug mills)... 

Auger machines, cutting tables Brick machines, dry press, granulator Mixer, pug mill, rolls Centrifuges Compressors... 

Another type of mixer is the pug mill, in which roughly two S-shaped, intermeshing blades revolve in opposite directions and at different speeds in an adjacent trough (Fig. 7.15). A high consistency (viscous) pigment-binder paste is subjected to a mechanical breakdown. The dispersion efficiency is, however, rather poor [7]. 

The procedures described above are used chiefly in fine ceramics. For plastic forming of coarse ceramics, it is common to use wet pan mixers or pug mills in which the wet mix is kneaded with rotating knives. Subsequent degassing in a vacuum chamber and extrusion are usual. 

The mixes are usually prepared in pan mixers and pug mills. The ware is then shaped by some of the following processes ... 

Among the first mixers other than drums and pug mills used for agglomeration was the Eirich mixer. In 1934 a patent was issued in Germany for the Eirich... 

Coal fines stored in bins (2) are discharged through several pantlegs (3) into a metering hopper (4). Variable speed discharge belts (8) under the bin (7) and hopper (4) meter the correct amount of each feed into the screw conveyor (9) the binder is pulverized in the hammer mill (10). Both components are premixed in a double screw mixer (11) and elevated (12) into another screw feeder (13). The latter discharges into two vertical pug mills (14) excess feed overflows at the end of the conveyor through a chute (30). 

Fig. 8.76a is a schematic cross section through an extruder with vacuum degassing. It shows first the end of the mixing/conditioning equipment (in this case an open pug mill but more commonly a closed paddle or screw mixer/ conditioner [see, for example, Fig. 8.70, Section 8.4.2]) in which the feed is prepared for extrusion. The mass is then densified in a pug sealer in which a compacted plug of material is formed that provides a dynamic seal against the vacuum that is created in the feed chamber of the extruder. While dropping into the extruder screw by gravity, gas is removed from the particulate mass. Alternatively, there is a vertical feeder/sealer (Fig. 8.76b) for smaller capacities which mounts directly to the vacuum chamber of the extruder and accomplishes a similar degassing effect.

Fig. 11.13 Photograph of different tumble/growth agglomeration work modules that are attached to the all purpose drive stand of Fig. 11.12. (a) disc or pan agglomerator (b) coating pan (c) bowl blender (d) planetary bowl blender (e) double cone blender (f) cube mixer (g) high shear mixer (h) pug mill/kneader (courtesy Erweka, Heusenstamm, Germany).

One of the major problems associated with the wet granulation of fertilizers is the very reason why the wetted particulate mass agglomerates and forms granules. The moistened solid particles not only adhere to each other but also to equipment walls and parts. This build-up can not be avoided and must be controlled. In mixers employing agitators, such as pug mills, ribbon blenders, or Errich-type pan mixers, the tools them-... 

During normal operation fresh pre-mixed (if applicable) feed (2) and recyclate (18) are proportioned by rotary gates and weigh belts (3). The ratio of fresh feed to recyclate should be kept constant it is only adjusted if the level controls in bins (2) and (18) require modification of compactor feed composition. Typically a changed relationship fresh feed to recyclate necessitates readjustment of the compactor (8) and, sometimes, the oversize crusher (16) parameters. Fresh feed and recyclate are homogenized in a low-intensity mixer (e.g.,. pug mill, mix muller) (4) and transported by buck-... 

Most plants use hardwood charcoal (F), which is crushed to < 3 mm (1), stored in a small surge bin (2), and then mixed with the binder. Often premixing occurs in a simple paddle mixer (3) and conditioning in a double shaft vertical pug mill ((4) called vertical fluxer), similar to the one shown in Fig. 6.10-21 but without steam injection. A typical mix formulation consists of 76% charcoal, 4% pregelatinized starch, and 20%... 

The amount, quantity, or total produced. Something resulting from or necessarily following from a set of conditions. A paddle type mixer usually with open top, single or double shafts, and trough shaped chamber, (see also VERTICAL PUG MILL)... 

Any type of solids conveyor may be suitable for recycle mixing however, the most universally applicable is the double-shaft pug-mill-type paddle mixer. This conveyor or mixer should be insulated to prevent excessive heat losses from the hot, dry recycle product. To ensure uniformity in the recycle operation, a surge storage reserve of recycle solids should be installed for startup purposes and in the event of interruption of product discharge from the cylinder. In recycle operations, 50 to 60 percent product recirculation is found economical in many instances. 

The most universally applicable mixer suitable for recycle mixing is the double-shaft, pug-mill-type mixer [28]. This mixer should be insulated to prevent excessive heat losses from the hot, dry recycle product. Moreover, a surge tank of... 

Pug Mill a shaft mixer with a closed barrel instead of an open trough the term pug mill should not be confused with PUG (q.v.)... 

Different devices for wetting Fluidized bed fly-ash will be studied rotating screw, pug mill, drum. The problem of wet ash transport will be studied as well. Concrete rotating mixer tracks have already been tested it is a costly solution but it gives encouraging results. 

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