ABSTRACT
Gravity settlers that use inclined surfaces in the form of flat plates or tubes have the effect of increasing the settling rate of the particulates. Sedimentation is a separation of solid particles from a suspension under action of a body force, which may be either gravity or centrifugal, on the buoyant mass of the particle. The gravity flux of solids goes through a maximum as the concentration increases, as obtained from batch sedimentation tests for various concentrations. For most zone settling slurries, the combination of gravity and bulk flow flux terms produces a total flux curve with a maximum and minimum. In the thickening region, solids move toward the underflow both by gravity sedimentation and by bulk movement resulting from underflow withdrawal. A thickener is a sedimentation basin that is employed to concentrate a slurry prior to filtration or centrifugation. In designing a thickener, the areas needed for clarification and thickening are therefore examined separately.
