Experimental verification of a mathematical model for quiescent settling of a flocculating slurry

Quiescent settling experiments were carried out with ferric hydroxide flocs to test a previously proposed theoretical model for settling. The model for orthokinetic flocculation includes a catch-up mechanism associated with the different fall velocities of particles of different sizes, and a turbulence mechanism resulting from the eddies caused by the dissipation of energy by the falling particles. Adjustment of parameters to yield settling velocities in agreement with experimental results at settleable solids volume fraction (SSVF) of 0.03 and 0.20 yielded plots in good agreement with the experimental data over the entire range of SSVF.