Chapter 2
Figure 2.4 shows a typical profile for U[2]. When two droplets are very close
(ft→O), attractive forces dominate and droplets are expected to aggregate
irreversibly, which is referred to as coagulation. When h reaches secondary
energy minimum, droplets may form aggregates reversibly that can be
re-dispersed which is usually termed flocculation. Generally aggregation is used
to describe either coagulation or flocculation.
Primary minimum (coagulation)
h (nm)
Figure 2.4 Energy of interaction between two spherical droplets [2]
If L∕max ≤0, there is no energy barrier to prevent the two surfaces from
approaching each other. In this case, so-called fast aggregation takes place. On
the other hand, if l∕max > 0, an energy barrier must be overcome to achieve
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