The Stringent Wastewater discharge limits made the process modelling software an inevitable asset to many process-engineering companies. Process modelling provides a better understanding of new plant designing, upgrading the plant, optimizing the existing plants, and improvements in process control. It also helps to select the lowest CAPEX-OPEX solutions, in troubleshooting, to train the stakeholders, and nowadays even used to predict the greenhouse gas footprint of a treatment plant.