The GSA-GLUE approach for uncertainty assessment of an integrated MBR model

In the recent literature, the uncertainty of wastewater treatment plant (WWTP) modelling has had relevant interest both for designers and operators. Indeed, the frequent data lacking and the need to improve process knowledge, in case of innovative technologies, make the use of mathematical models more uncertain. Therefore, the need to make model uncertainty more explicit is warmly recommended. However, only few applications of uncertainty analysis in the wastewater field have been carried out. In this work, the combination of the global sensitivity analysis (GSA) and the Generalized Likelihood Uncertainty Estimation (GLUE) is applied for the uncertainty assessment of a WWTP model, in order to discuss and verify its applicability. In particular, the GSA-GLUE approach is applied to an integrated membrane bioreactor (MBR) model able to simulate the biological nutrient removal processes occurring in a University Cape Town (UCT)-MBR system. The model under study is also able to simulate the physical processes of cake layer formation on membrane surface and the particle retention inside the cake layer. The GSA-GLUE approach has been applied by using quantity-quality data acquired in a UCT-MBR pilot plant. The results have demonstrated that the GSA-GLUE approach can be a valuable tool for designing and managing WWTP