4. Sedimentation theory

Sedimentation modelling is due to Kynch (1952), who proposed the following theory: the falling velocity of rigid particles in free sedimentation depends only on the local solid concentration of the suspension. It is a decreasing function of solid concentration. Particles of the same size, shape and density are equitominant, and their concentration is uniform at each level of the sedimentation column.

Thus, based on test specimens, Kynch plots isoconcentration lines in the diagram (h, t ) corresponding to levels where the concentration has a given value C, and their displacement over time (figure 5 ). The slope of these lines is given by :