Separation of Solids from Fluids by Sedimentation

Sedimentation involves particle motion in gravitational, centrifugal, magnetic, and electrical fields, and is used in chemical, biological, and environmental processes 

Sedimentation in a Gravitational Field Usually, the acceleration phase until a constant sedimentation velocity is reached is negligible (Example 3.4.8). Thus particle sedimentation in a gravitational fleld is described by the balance of forces on a particle moving with constant velocity (steady-state), that is, the weight (less the lifting force) equals the hydrodynamic resistance. For spheres (Section 3.4.1.2) we have  

Example 3.4.9 shows how to estimate the size of a sand trap by Eq. (3.4.55). 

Equation (3.4.55) does not consider that the sedimentation process may be hindered by the interactions of particles with each other. In case of a volume content of the particles (ey) of more than about 5%, the sedimentation velocity is substantially lower than calculated by Eq. (3.4.55). An empirical correlation to account for this effect is  

Separation of solids from gases (dust removal) 

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