Grit Removal...

Wastewater contains a certain amount of inorganic, relatively heavy material. This includes sand, bits of hard plastic, glass, pebbles, etc. These materials are abrasive and can prematurely wear pumps and other equipment. There are several common methods of removing grit. This facility uses a centrifugal grit seperator. The wastewater enters a small, circular tank at a tangent. This produces a circular flow pattern. Centrifugal force causes the heavier matter to move to the center bottom of the chamber. There they through an opening into a temporary holding tank. The grit is periodically pumped out, dewatered, disposed of at the landfill.

1999 © Toprak Home Page...

Grit : sand, gravel, corn kernels, bone chips, coffee grounds.
Purpose of removal : (1) prevent excessive abrasion of mechanical equipment ; (2) prevent deposition of grit in pipes and channels (that eventually would lead to clogging) ; (3) reduce accumulation of grit in downstream units such as settling basins and digesters.
Aerated grit chamber : diffused air keeps organic solids in suspension as grit settles.



Square, clarifier-type : grit washing necessary to remove heavier organics.
Horizontal flow : was used in past, but rarely used today.
Purpose of "pre-aeration" in grit chambers : (1) freshen wastewater ; (2) remove gases ; (3) improve settling downstream.

"Centrifugal Grit Chamber"...