QFT Control of Dissolved Oxygen Concentration in a Wastewater Treatment Pilot Plant

The paper deals with the robust control of the dissolved oxygen concentration in the case of wastewater treatment processes from milk and beer industry. The QFT robust control method has been chosen for the dissolved oxygen concentration control. Firstly the dissolved oxygen control loop was identified. The QFT controller and prefilter were designed so that the behaviour of the closed loop system be bounded by the limits (upper and lower) imposed to the system. The QFT control of the dissolved oxygen concentration was tested using an experimentally pilot plant that is also presented in the paper.