Efficiency of selected shapes of grit chamber troughs

Grit is usually removed from sewage flow just prior to treatment by some type of grit chamber, often little more than a wide channel with a depressed trough to trap the grit. Three shapes of grit chamber troughs were studied in a model to determine which was the most efficient for the selective capture of grit. The model was constructed of wood, with plastic, interchangeable troughs, and was six inches wide by about ten feet long, including a three foot approach channel to the chamber. The three troughs were six inches deep with 2:1, side slopes and differed, therefore, only in bottom length. Trough 1 tapered to a point, Trough 2 had a four inch bottom length, and Trough 3 had an eight inch bottom length. Water from a town main was run through the apparatus at velocities varying from 0.11. to 0.8 fps and depths from 0.1 to 0.33 feet. Grit was added, as the flow entered the approach channel, through a funnel. Ordinary construction sand was used as grit after being sieved to obtain 0.1 and 0.2 mm diameter particles. When all the grit had been added the flow was stopped and all grit which had not passed the trough was removed and measured. This measurement when compared with the known amount of grit which was added produced a value of per cant grit passing the trough for each run. Trough 2, the medium length trough, was found to be relatively most efficient for the selective capture of grit.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Sanitary Engineering

Department dc:contributor.department

Sanitary Engineering

Grantor dc:publisher

Virginia Polytechnic Institute

Year dc:date.issued

1964

Author dc:creator

• Van Natta, Craig

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en_US

Handle dc:identifier.uri

http://hdl.handle.net/10919/76362

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/76362