Optimization of the Anaerobic-Anoxic-Oxic Process by Integrating ASM2d with Pareto Analysis of Variance and Response Surface Methodology

Wastewater treatment plants (WWTPs) are high-energy-consuming units. Reasonable operation strategies can enable WWTPs to meet discharge standards while reducing the operating cost. In this study, activated sludge model 2d (ASM2d), Pareto analysis of variance (ANOVA), and response surface methodology (RSM) were jointly used simulate optimize a lab-scale anaerobic-anoxic-oxic (AAO) reactor. The optimization objective was determine optimal design operational parameters (DOPs) that could enhance both pollutant removal energy saving. DOPs had significant influence on objective, such as retention time (SRT), dissolved oxygen (DO), ratio biodegradable chemical demand total nitrogen (BCOD/TN), identified by ANOVA. with SRT 15 days, DO concentration 0.5 mg/L, BCOD/TN 5.21 determined RSM. Under conditions, efficiencies NH4+-N, (TN), phosphorus (TP) 96.2%, 76.8%, 92.8%, respectively, annual cost $26.4. Furthermore, combination validated using pilot-scale AAO system. TN TP improved 11.0% 5.0%, be reduced 15.0%. Overall, study confirmed method integrating ASM2d ANOVA RSM effective in optimizing wastewater processes.