Modelling of wastewater treatment plant operation under variable conditions

Abstract

Modelling of the wastewater treatment plant in Żory, Poland was carried out using the BioWin 2.1 simulation program based on the real data regarding acquired in 2016-2017. It was made the static and dynamic calibration of the developed model of the treatment plant. The calibration and verification procedure was performed. In order to determine the optimal working conditions for the WWTP Żory, a series of simulation tests were carried out (44 simulations of the WWTP Żory model work). The simulations were carried out for: variable wastewater temperature, uniform and uneven distribution of wastewater to individual biological sequences, at variable sludge age and rate of the internal recirculation, and variable oxygen concentration in the nitrification and denitrification tanks. It was also investigated the influence of the external carbon source dosing, and the management method of wastewaters recycled from dewatering system, on the effectiveness of nitrogen removal in simulation conditions. The simulation studies resulted in determination of the optimal parameters for the WWTP Żory work, considering the variable inflow parameters, in order to intensify removal of the nitrogen compounds by biological means, and to achieve the target concentration of the total nitrogen at the outlet, i.e. 10 mgN/L.