Articles | Volume 10, issue 2
Research article
15 Aug 2017
Research article |  | 15 Aug 2017

Flow intake control using dry-weather forecast

Otto Icke, Kim van Schagen, Christian Huising, Jasper Wuister, Edward van Dijk, and Arjan Budding

Abstract. Level-based control of the influent flow causes peak discharges at a waste water treatment plant (WWTP) after rainfall events. Furthermore, the capacity of the post-treatment is in general smaller than the maximum hydraulic capacity of the WWTP. This results in a significant bypass of the post-treatment during peak discharge. The optimisation of influent flow reduces peak discharge, and increases the treatment efficiency of the whole water cycle, which benefits the surface water quality. In this paper, it is shown that half of the bypasses of the post-treatment can be prevented by predictive control. A predictive controller for influent flow is implemented using the Aquasuite® Advanced Monitoring and Control platform. Based on real-time measured water levels in the sewerage and both rainfall and dry-weather flow (DWF) predictions, a discharge limitation is determined by a volume optimisation technique. For the analysed period (February–September 2016) results at WWTP Bennekom show that about 50 % of bypass volume can be prevented. Analysis of single rainfall events shows that the used approach is still conservative and that the bypass can be even further decreased by allowing discharge limitation during precipitation.

Short summary
Flow intake based on predictive control using dry-weather flow and rainfall predictions offers reduced peak discharges on the waste water treatment plants. This results in a better performance of the waste water treatment plant and particularly the utilisation of the post-treatment phase. Results at waste water treatment plant Bennekom show that about 50 % of bypass volume of the post-treatment phase can be prevented with operational predictive control. This improves the surface water quality.