ABSTRACT
In this chapter, we focus on primary sedimentation-the use of large basins in which primary settling is achieved under relatively quiescent conditions (see Figure 8.1). Within these basins, the primary settled solids collect and are mechanically scraped into a hopper, from which they are pumped to a sludge-processing area. Oil, grease, and other floating materials (scum) are skimmed from the surface. The effluent is discharged over weirs into a collection trough.
