Skip to main content


Buy Article:

$17.50 plus tax (Refund Policy)

Or sign up for a free trial


Controversy continues among wastewater treatment facilities owners and operators, consulting engineers, and process equipment manufacturers and their representatives as to the advantages and disadvantages of alternative sludge collection mechanisms for secondary clarifiers in the activated sludge process. This paper summarizes the four alternative collector mechanisms available while presenting an evaluation of the advantages and disadvantages of each mechanism. These evaluations incorporate the results of several recent engineering studies.

The paper concludes that, from a process perspective, the suction plenum or Tow-Bro mechanism offers significant advantages over all presently available mechanisms and recommends that new secondary clarifiers or retrofitted existing secondary clarifiers utilize this design.

This paper concludes by suggesting that additional improvements in the design of secondary clarifiers may be achieved in the future through the use of mathematical models of the secondary clarifier coupled to existing models of the activated sludge process and the flow regimes in which these systems operate.

Document Type: Research Article


Publication date: 2002-01-01

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 These proceedings are not peer reviewed.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 ContentFree content
  • Partial Free ContentPartial Free content
  • New ContentNew content
  • Open Access ContentOpen access content
  • Partial Open Access ContentPartial Open access content
  • Subscribed ContentSubscribed content
  • Partial Subscribed ContentPartial Subscribed content
  • Free Trial ContentFree 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