ABSTRACT
The behavior of colloids concentrated at an interface is strongly affected by surface interactions that occur on the nanoscale between colloids and between the colloids and the surface. This chapter shows how the concept of solid pressure can be a good vehicle to account for particle–particle interactions in the macroscopic description of separation processes like membrane filtration, sedimentation, or drying. It also shows how solid pressure can be related to the way a suspension resists an increase in concentration. The chapter illustrates in which way the change of state of the suspension, can be put in relation to the various forms of accumulation on a surface, both from a theoretical and an experimental point of view. The resistance of the dispersion to over-concentration will be defined by osmotic pressure variation and this resistance will be linked to a Peclet number relative to the filtration conditions.
