Powder heaps, segregation

Fig. 7 Segregation in powder heaps. Finer particles are illustrated in black and coarser particles are in white. (Reprinted from Ref by courtesy of Marcel Dekker, Inc.)...

Fig. 1.1 Segregation of powders when poured into a heap.

Handling of free-flowing powders can result in size segregation hence the distribution of particle size in a powder depends upon its previous history. If free-flowing powder is poured into a heap there is a tendency... 

If the powder has been charged on the conveyor, fines concentrate at the center of the belt while coarse particles roll to the outer edges such as the segregation seen when sampling from a heap. 

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