Skip to main content

USING SHOTCRETE FOR REPAIR OF CONCRETE STRUCTURES IN A HIGH PURITY OXYGEN ACTIVATED SLUDGE SYSTEM

Buy Article:

$17.50 plus tax (Refund Policy)

Or sign up for a free trial

Abstract:

The County Sanitation Districts of Los Angeles County (Districts) treat 8.8 m3/s (200 mgd) of wastewater using a high-purity oxygen activated sludge (HPOAS) process at its main wastewater treatment plant, the Joint Water Pollution Control Plant (JWPCP) in Carson, California. This secondary treatment process has produced high quality secondary effluent for 16 years. Because the JWPCP HPOAS system utilizes enclosed reactors, carbon dioxide (CO2), a product of oxidation of organic material, builds up in the reactor head spaces. High concentrations of CO2 in solution have resulted in carbonic acid formation. The carbonic acid has caused considerable deterioration to occur in equipment and structures in the secondary treatment process trains. Up to 1.3 cm (0.5 inch) of section loss in some concrete structures has been observed. To repair and replace deteriorated concrete, a pneumatically applied cementitious overlay is being used. Testing of different surface preparations, application techniques, and overlay materials has shown that if the concrete surface is adequately prepared and if a high quality, low water-tocement ratio, silica fume rich cement mix is used for the overlay, the new material will have excellent adhesion to the existing concrete and very low permeability. Accelerated corrosion testing indicated that the cementitious overlays will significantly decrease the rate of concrete deterioration occurring at the JWPCP.

Document Type: Research Article

DOI: https://doi.org/10.2175/193864700784546053

Publication date: 2000-01-01

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 These proceedings are not peer reviewed.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
X
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