Efficiency of a turbidity-based, real-time control strategy applied to a retention tank: a simulation study

This paper compares several real-time control (RTC) strategies for a generic configuration consisting of a storage tank with two overflow facilities. Two of the strategies only make use of flow rate data, while the third also introduces turbidity data in order to exercise dynamic control between two overflow locations. The efficiency of each strategy is compared over a wide range of system setups, described by two parameters. This assessment is performed by simulating the application of control strategies to actual measurements time series recorded on two sites. Adding turbidity measurements into an RTC strategy leads to a significant reduction in the annual overflow pollutant load. The pollutant spills spared by such a control strategy strongly depend on the site and on the flow rate based strategy considered as a reference. With the datasets used in this study, values ranging from 5 to 50% were obtained.