Comparison of guideline- and model-based WWTP design for uncertain influent conditions

Abstract

In this study, two methods for wastewater treatment plant (WWTP) dimensioning were compared: (1) a traditional guideline-based approach, and (2) a mechanistic model-based approach. The design outputs depended on uncertainties in correlated influent concentrations, which emphasises the importance of uncertainty analysis. The results showed that model-based design could simplify and reduce the time required for uncertainty and sensitivity analysis compared to a conventional design approach, in which the equations are solved manually and iteratively. A benefit of the conventional design approach was the simple interpretation of which factors limited the design capacity. In the end, this study shows the potential, as well as the need for, model-based design of WWTPs. HIGHLIGHTS Process model-based design can simplify uncertainty and sensitivity analysis compared to a conventional design approach.; Process models are more detailed than traditional sizing calculations and may require design pre-requirements to be specified in more detail.; Typical assumed design parameter values differ from the output of mechanistic models.;

Keywords

• sensitivity
• design
• guideline
• influent concentrations
• simulation