Modeling and Performance Evaluation of a full scale Petrochemical WastewaterTreatment Process

Evaluation and modeling of the wastewater treatment plants (WWTP) have to be based on the fact that the pollutant concentrations and flow rates change constantly. In addition, different approaches must used due to there are different processes in a WWTP. A Mexican petrochemical complex has a WWTP that processes wastewaters from several petrochemical plants, where the flow rates and pollutant concentrationschange constantly. The actual WWTP has an equalization pond (EP) followed by an aerated lagoon (AL). The EP performance was evaluated by CFD tool and it was possible to evaluate the equalization pond performance. In the biological process, a more realistic dynamical model to evaluate the AL performance was developed and calibrated. The reactor was modeled as a plug flow reactor with high dispersion, due to there is no biological sludge recirculation. It was found that with an increase of 12.5% in the wastewater flow rate the Mexican regulation will not be satisfied The model improves modeling because considers different actual operational factors as lost of VOC and variations of temperature, influent COD and flow rate, which have tremendous impact on the petrochemical wastewater treatment plant performance.