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Bioprocess and Biosystems Engineering

, Volume 27, Issue 4, pp 223–228 | Cite as

Feedforward-feedback control of dissolved oxygen concentration in a predenitrification system

  • Ma YongEmail author
  • Peng Yongzhen
  • Wang Shuying
Original papers

Abstract

As the largest single energy-consuming component in most biological wastewater treatment systems, aeration control is of great interest from the point of view of saving energy and improving wastewater treatment plant efficiency. In this paper, three different strategies, including conventional constant dissolved oxygen (DO) set-point control, cascade DO set-point control, and feedforward-feedback DO set-point control were evaluated using the denitrification layout of the IWA simulation benchmark. Simulation studies showed that the feedforward-feedback DO set-point control strategy was better than the other control strategies at meeting the effluent standards and reducing operational costs. The control strategy works primarily by feedforward control based on an ammonium sensor located at the head of the aerobic process. It has an important advantage over effluent measurements in that there is no (or only a very short) time delay for information; feedforward control was combined with slow feedback control to compensate for model approximations. The feedforward-feedback DO control was implemented in a lab-scale wastewater treatment plant for a period of 60 days. Compared to operation with constant DO concentration, the required airflow could be reduced by up to 8–15% by employing the feedforward-feedback DO-control strategy, and the effluent ammonia concentration could be reduced by up to 15–25%. This control strategy can be expected to be accepted by the operating personnel in wastewater treatment plants.

Keywords

Energy-saving Feedforward-feedback control DO control Predenitrification 

Notes

Acknowledgements

This work was supported by the key project of the National Natural Science Foundation of China (NSFC) (50138010), Key Technology Project of Beijing Municipal Education Commission (Kz200310005003), and The Project of Beijing Science and Technology Committee (H020620010120).

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Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  1. 1.School of Municipal and Environmental EngineeringHarbin Institute of TechnologyHarbinChina
  2. 2.Key Laboratory of Beijing for Water Quality Science and Water Environmental Recovery EngineeringBeijing University of TechnologyBeijingChina

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