CONTROL STRATEGY FOR THE ACTIVATED-SLUDGE PROCESS UNDER SHOCK LOADING

A two-hierarchical-level control strategy for the activated sludge wastewater treatment process was developed. The super level control is a fuzzy control system for bringing the process to the optimal operation state. The lower level control consists of two proportional-integral-derivative feedback controllers for maintaining the concentration of the dissolved oxygen in the aerator and the height of the sludge blanket at the bottom of the clarifier at the set-points. The simulation of the activated sludge process showed that such a control strategy could improve the process performance, especially in the case of shock loading.