Control of distributed tanks for stormwater treatment in combination with a wastewater treatment plant and a sewer system

In North Rhine-Westphalia (Germany) contaminated rainwater by traffic and industry areas could not pass into flowing waters without cleaning. Therefore, many purification tank for rainwater (PTR) have to be built in areas with separate sewers for rainwater and wastewater. The heavy polluted rainwater has to be transmitted over the wastewater treatment plant. The wastewater treatment plant and sewer are constructed only for the past wastewater quantities. Aggravatingly the inflow is added. For this reason, the wastewater treatment plant and sewer are strongly working close by full capacity during rain events. The additional wastewater caused by PBR can lead to an overload of the wastewater treatment plant sewer. This has the consequence of unsettled wastewater in nature. The goal of pollution reduction in flowing waters would be merged thereby. In this case, PTRs have to be controlled centrally. If enough capacity in the wastewater treatment plant and sewer is available each PTR by each PTR could be pumped dry. For this control application a PTR-controller is developed. The controller is tested in simulation tool simba#water. Thereby the operability of the PTR-controller and the discharge for sewer and wastewater treatment plant could be verified.