Skip to main content

Application of a CFD Model to improve the Performance of Rectangular Clarifiers

The full text article is not available for purchase.

The publisher only permits individual articles to be downloaded by subscribers.

or click here to sign up for a free trial


There has been a long standing debate about the relative merits of circular and rectangular clarifiers. Both have been shown to be capable of excellent performance and both have experienced problems. The hydrodynamics of each configuration under similar hydraulic loading differ in fundamental aspects that determine what types of geometric modifications are likely to improve the clarifier performance. Griborio (2004), Griborio and McCorquodale (2005) and McCorquodale et al. (2005) presented the development and application of a computational fluid dynamics (CFD) model for predicting the performance of circular clarifiers under different geometric configurations. This paper uses a 2-D CFD model to investigate the response of a secondary rectangular settling tank to various internal modifications. Among the salient features of this model are: (1) discrete, zone and compression settling; (2) flocculation; (3) non- Newtonian flow; (4) floatable particles; (5) variable internal tank options including skirts and perforated baffles.

A simple rectangular tank with no special treatment was selected to demonstrate the response of rectangular tanks to different internal geometries. The selected clarifier is the Tomelilla secondary settling tank, which is describe by Larsen (1977). This tank was selected because performance data are available for model calibration, and because it represents a marginal performance case. After calibration, the model was used to evaluate different internal configurations. For the simulated trials, the best combination was an inlet skirt and an extended inboard launder with a perforated baffle.

Document Type: Research Article


Publication date: January 1, 2006

More about this publication?
  • Proceedings of the Water Environment Federation is an archive of papers published in the proceedings of the annual Water Environment Federation® Technical Exhibition and Conference (WEFTEC® ) and specialty conferences held since the year 2000. These proceedings are not peer reviewed.

    WEF Members: Sign in (right panel) with your IngentaConnect user name and password to receive complimentary access.
  • Subscribe to this Title
  • Membership Information
  • About WEF Proceedings
  • WEFTEC Conference Information
  • Ingenta Connect is not responsible for the content or availability of external websites

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Partial Open Access Content
Partial Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more