Grit Classifier

Grit Classifiers or also known as grit screws, grit separators, or grit classifiers are used at wastewater plants at the headworks (front end of the plant) to help separate the grit from organics and water.
Grit removal needs to be done at the headworks of plants to help reduce wear to upstream pumps and mechanical equipment. Grit can also cause pipe blockage and reduce the effective volume of the treatment basins. Grit classifiers usually consist of a hopper positioned on top of an inclined screw conveyor. Typically grit classifiers are made of stainless steel housing and have a high strength abrasion resistant fights on the screw because of the abrasive application.
All types of grit classifiers typically receive a grit slurry from an airlift pump or a grit pumps) Most classifiers receive a grit slurry that is 1-3% solids mixture. The hopper of a traditional grit classifier is designed for the shortest retention time to allow heavier grit to settle, but not the lighter organic material. The organic material is carried out of the hopper with the grit-free overflow and is returned to the plant’s process. As the grit is carried up the incline and passes the water line elevation, rotating avery slow RPM screw conveyor, allows time for the water to drain back into the hopper. The screw conveyor conveys the grit out of the system and usually into a dumpster to then be hauled to a landfill.
Adventages:
Low-speed shafted conveyor dewaters grit as it conveys beyond the water surface.
External bearings for better access, visibility, and reduced maintenance costs.
Enclosed to avoid exposure and for odor control.