N-Removal on Wastewater Treatment Plants: A Process Control Approach

Ramon Vilanova, Reza Katebi, NoraLiza Wahab

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DOI: 10.4236/jwarp.2011.31001                

Abstract

A multilayered control design approach is proposed here. Starting with the Dissolved Oxygen (DO) control loop in the last aerated tank, the control of the recirculation sludge is added next. Once the limitations of this two-loop control strategy are highlighted, a cascade control loop is proposed. This cascade control is further enhanced by a feed-forward control action that makes use of influent ammonia concentration. The resulting cascade+feedforward control configuration achieves satisfactory nitrogen removal for the three influent operating conditions (dry, rain and storm.)

Keywords

Wastewater Process Control, Nitrogen Removal, PID Control

Conflicts of Interest

The authors declare no conflicts of interest.

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