ABSTRACT
Grit includes sand, dust, cinder, bone chips, coffee grounds, seeds, eggshells, and other materials in wastewater that are nonputrescible and are heavier than organic matter. This chapter presents the design information on various types of grit removal facilities. It provides design procedure and equipment details, operation and maintenance, and equipment specifications for aerated grit removal facility in the design example. The chapter shows that the advantages and disadvantages of having a grit removal facility installed at different locations. Grit is removed from wastewater by gravity settling or by centrifugal force. Gravity settling is encountered in many treatment units. There is no significant interference between the settling particles, and the particles settle as individual entities. Many systems are used to remove grit along with organic solids. Degritting of sludge is necessary to separate grit from the organic solids. Degritting devices include cyclones, centrifuges, and detritus tanks.
