Agglomeration wanted

The time available for the drops to dry depends on their average velocity and the radius of the dryer (Figure 14-13). In the small machine you want a small radius you get this by minimizing the velocity of the drops. This requires low ejection velocities and low air circulation velocities. (The two are related). In the large machine drops have to move away quickly from the atomizer to minimize collisions and agglomeration. This is a very different requirement. 

Even though the prevention of undesirable agglomeration is a potentially important, but mostly neglected, part of agglomeration science (see Section 1.3), this book is mainly devoted to wanted, desirable agglomeration and the procedures or methods to accomplish size enlargement by agglomeration. 

Table 24, Wanted and unwanted agglomeration in various product areas...

W. Pietsch, Erwiinschte Agglomeration mit Granulatformmaschinen. (Wanted agglomeration with pelleting machines.) Maschinenmarkt MM - Industriejournal 77 (1971)10, 193-196. W. Pietsch, Size enlargement of solids. Particulate Matter (Bulletin of the Powder Advisory Center) 2 (1971)1, 15-22. 

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