HOLISTIC APPROACH TO DESIGN OF DISSOLVED OXYGEN CONTROL SYSTEMS
Abstract:Many dissolved oxygen (D.O.) control systems installed at wastewater treatment plants are not in operation due to poor reliability. Poor reliability often is associated with either undetected hardware problems (usually D.O. sensors faults) or with unstable control. Investigation of several state-of-the art control and hardware fault detection algorithms is reported in the paper. Application of a pattern recognition algorithm allowed revealing of such difficult to detect problem as sensor drift within 8 hours after the drift started while air flow was still within 10% of normal value. Applications of Case Based Reasoning (CBR) instead of PID for calculation of airflow and blower control allowed not only avoiding stability problems but also operation of D.O. control system for more than 5 hours without receiving a signal from D.O. sensor. Modeling of aeration system using Matlab/Simulink modeling software showed that D.O. control systems utilizing PID based pressure blower control are inherently unstable. They can be improved, however, by continuously changing integral reset time based on operating conditions.
Document Type: Research Article
Publication date: January 1, 2004
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 These proceedings are not peer reviewed.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
- ingentaconnect is not responsible for the content or availability of external websites