Basic concept of the Wastewater Model

This library offers tools to make an advanced model for a wastewater treatment plant including sludge treatment. As modelling base the ASM1 and the ADM1 were chosen and can be adapted to the individual needs. The library can be used in teaching, research and as well in optimisation of existing WWTP. The model starts always with a source, where the concentrations, the flow rate and the temperature are defined. The flow is directed to the wastewater sink(s). All internal flows like recirculation, or dividing has to be realised with pumps to fulfil the requirements of a flow variables in modelica.

For every flow variable in modelica, a potential variable is required. For a flow this should be the pressure, but we don’t make hydrodynamic modelling. Therefore, the temperature is chosen to be the potential variable an in declared in the inflow. The stream variables are not declared as stream variables, because the our wastewater components are grouped in form of records. For stream variables don’t work with records. It is not possible to add
variables we have to use the prefix input or output. This explications may confuses, but you are getting it while reading the part where the connectors are explained.

The modelling can be done graphically. You can create a new model and place the sub-model via mouse to the new model. The model without icons are not intended for the direct use. Now you can connect the model with the mouse clicking on a output connector,
moving the mouse to an input connector and clicking here again. Then a line should be sketched. You can click on the way as well to achieve a better looking line. If the model is complete, please save it. If no error occurs, you can run the model and have fun.