Skip to main content


Buy Article:

$9.50 plus tax (Refund Policy)

Or sign up for a free trial

The purpose of this paper is to undertake a comparative analysis of the activated sludge (AS) and aerated stabilization basin (ASB) treatment processes with a focus on application to the pulp and paper industry. AS systems can achieve higher BOD percent removals, but for the systems studied, the minimum effluent BOD concentrations of the two systems were equivalent. A key advantage of the AS system is a very small footprint which not only leads to advantages in overall size, but, potentially, in off-gas collection and leakage control. ASB systems have typically lower capital, energy, and O&M costs than comparable AS systems. ASB systems are more forgiving in responding to influent quality and flow variations and are simpler to operate. For the systems studied the nutrient discharges were equivalent, but supplemental nutrient addition rates were much higher for AS systems. The waste solids process is a continuous, separate operation in an AS system. Settled secondary solids in an ASB system reduce in volume through hydrolysis to typically ten percent concentrations. At periods up to twenty years the accumulated solids must be dredged, dewatered, and disposed. ASBs, because of their longer hydraulic retention times, tend to have their effluent wastewater approach ambient air conditions. This is desirable during summer conditions, but can be a treatment problem during the wintertime – particularly in northern Canadian sites. Loss of an insulating foam cover is a greater problem for ASB systems. AS systems typically require supplemental cooling equipment to resolve high influent temperature conditions.

For the authors each system has advantages that make the selection of one system over the other a site-specific decision. Clearly, when the footprint is a major factor the AS system is favored. For reliability, ease, and cost of operation it appears that the ASB is favored. For pulp and paper application, the reliability of a wastewater treatment system to eliminate the need for production curtailments is a critically important factor in comparing AS and ASB systems. In this area, the authors have found the ASB system to be superior.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Article Media
No Metrics

Document Type: Research Article

Publication date: 2001-01-01

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.

    A subscription to the Proceedings of the Water Environment Federation includes access to most papers presented at the annual WEF Technical Exhibition and Conference (WEFTEC) and other conferences held since 2000. Subscription access begins 12 months after the event and is valid for 12 months from month of purchase. A subscription to the Proceedings of the Water Environment Federation is included in Water Environment Federation (WEF) membership.

    WEF Members: Sign in (right panel) with your IngentaConnect user name and password to receive complimentary access. Access begins 12 months after the conference or event
  • Subscribe to this Title
  • Membership Information
  • About WEF Proceedings
  • WEFTEC Conference Information
  • Learn about the many other WEF member benefits and join today
  • Ingenta Connect is not responsible for the content or availability of external websites
  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed 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