A modified QWASI model for predicting fate and transport of micropollutants in a wastewater lagoon

A modified Quantitative Water Air Sediment Interaction (QWASI) fugacity model was developed for a municipal wastewater lagoon to study the fate and removal of seven representative micropollutants (MPs). The sunlight photodegradation and transformation rate constants, and sorption coefficients for the target MPs, were obtained experimentally to serve as model inputs. The model predicted that at least 65% of the concentration of the MPs remained in the outflow of the lagoon. The greatest removal was for triclosan (35%) and the least for carbamazepine (5%). Sensitivity analysis revealed that the lagoon inflow rate was the most important input factor.