Agglomeration pan

In order to coat each particle in a discrete manner and avoid agglomeration, the coating fluid must often be atomized more finely and in a more controlled manner than in the case where tablets are coated in a typical pan process. 

Fig. 3.10. Flow of material in a balling pan, indicating segregation and discharge of the largest agglomerates. (Courtesy Maschinenfabrik Gustav Eirich.)...

The influence of a number of the system variables relating to powder and liquid properties, etc., has already been discussed in Section 1 above. With proper control of these variables and of the pan operating conditions, it is possible within limits to influence agglomerate properties such as shape, size and porosity. A discussion of such factors has been given by Pietsch [24] and by Ball [25]. 

Fig. 3.11. Relationship between mean pellet size and residence time (throughput rate) as a function of liquid content for pan agglomerators [24,37].

The capacity data in Fig. 3.12 range between Q = 0.5jD2 Mg/h and Q = 1,2jD2 Mg/h whereas the installed power data in Fig. 3.13 range from P = Q.6D2 kW to P=2.3jD2kW. These quite broad variations in capacity and power requirements may be explained by variations in rotational speed, pan depth and inclination, feed density and by different requirements in agglomerate properties such as size and porosity. The manufacturers quoted data are generally more conservative than those quoted by Pietsch [24], which is to be expected. 

Paddle mixers, see Pugmills Pan agglomerators, see Disc agglomerators Peg granulator, see High speed shaft mixers... 

For a solid matrix, spraying a solution on particles under agitation (fluid bed or pan coating or agglomeration). 

This consists of agglomerating a powder into beads b moistening it as it rolls about in a rotating pan (I ig 6) Seed granules arc coated with humidified powder under... 

Numerous equipment types can be used for agglomeration, including horizontal ribbon and vertical mixers, rotary drums, zig-zag mixers, and pan agglomerators. Horizontal ribbon mixers as shown in Fig. 36.41 are used primarily for dry mix formulating, where only limited agglomeration occurs. They are comprised of a U-shaped trough and a ribbon or paddle-type agitator. Liquids are sprayed onto the surface of the dry material and slowly dispersed into the mix. Mixer operations can be either batch or continuous. 

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