Structure of Floes and Sediments

A factor of very great importance in the handling of colloidal dispersions is the structure of floes and sediments. Thus, in the filtration of a flocculated suspension it is necessary to have as open a structure as possible so that liquid can flow through the filter cake. 

The morphology of floes is determined to a large extent by the nature of the interparticle forces involved. Thus, if the particles arc strongly repelling but sediment under gravity or centrifugation, they tend to form a close-packed structure because the particles can slide across one another under the influence of Brownian motion and seek out a configuration of minimum 

The formation of a close-packed structure or clay on storage of a dispersion has to be avoided in many technical applications since such sediments are difficult to re-disperse (see Chapter 14). 

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