Sedimentation

Abstract

Sedimentation is the process of letting suspended material settle by gravity. It is accomplished by decreasing the velocity of the water being treated to a point in which the particles will no longer remain in suspension. When the velocity no longer supports the transport of the particles, gravity will remove them from the flow.

For example, in a glass cylinder, when solids diffuse through the interface, the process starts then to settle from slurry during a batch settling test and is assumed to approach terminal velocities under hindered settling conditions. Thus, several zones of concentration will be established. The particle is not actually sent all the way to the bottom of the cell, resulting in sediment. Rather, a low centrifugal field is used to create a concentration gradient wherein more particles are near the bottom of the cell than near the top. When the temperature decreases, the rate of settling becomes slower.