MODELLING AND IDENTIFICATION OF AERATION SYSTEMS FOR MODEL PREDICTIVE CONTROL OF DISSOLVED OXYGEN – SWARZEWO WASTEWATER TREATMENT PLANT CASE STUDY

Aeration is an important and expensive activity that is carried out during wastewater treatment plant (WWTP) operation. The aeration system serves as the actuator to deliver the airflow prescribed by the dissolved oxygen controller. It is on its own a complex dynamic system with nonlinear hybrid dynamics. Recently hybrid model predictive controllers (HMPC) were proposed in order to control the system valve and blower operation so that the required airflow can be accurately delivered and the energy cost due to blowing the air minimised. Availability of a suitable model of the aeration system is vital for a successful operation of these controllers. The paper improves the model recently proposed. A practical approach to the model identification and validation is proposed and applied to Swarzewo WWTP.