Optimizing Nitrogen Removal in a MBR Under Abnormal Operating Conditions
During startup and commissioning of a modified Ludzack-Ettinger (MLE) membrane bioreactor (MBR), Pima County Wastewater Management Division (PCWMD) staff were concerned with the total nitrogen concentration (TN) in the plant effluent. Whereas in the traditional MLE process, increasing recycle ratio increases the TN removal, in this particular process increasing the recycle ratio proved to actually decrease TN removal. Influent five-day biochemical oxygen demand (BOD5) was also found to be only 50% of design. The process was found to be very sensitive to recycle ratio due to oxygen entering the anoxic zones. Increased process control testing provided insights into the process operation. Based on these data, significant changes were made to equipment operation to lower the aeration basin dissolved oxygen (DO) concentration. In addition, the recycle ratio was managed to minimize oxygen transfer to the anoxic zones. These operational changes improved TN removal beyond that predicted in the Biowin® model used for design. This paper describes the findings related to the operation of this MBR facility under abnormal conditions and some of the factors that were found to impact TN removal.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
Document Type: Research Article
Publication date: 2006-01-01
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 These proceedings are not peer reviewed.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