Global predictive real-time control of Quebec Urban Community's westerly sewer network

Quebec Urban Community (QUC) has selected Global Predictive Real-Time Control (GP-RTC) as the most efficient approach to achieve environmental objectives defined by the Ministry of Environment. QUC wants to reduce combined sewer overflows (CSOs) frequency to the St Lawrence river to two events per summer period in order to reclaim the use of Jacques-Cartier Beach for recreational activities and sports of primary contact. QUC's control scheme is based on the Certainty Equivalent Control Open Loop Feedback (CEOLF) strategy which permits one to introduce, at each control period, updated measurements and meteorological predictions. A non-linear programming package is used to find the flow set points that minimise a multi-objective (cost) function, subjected to linear equality and inequality constraints representing the physical and operational constraints on the sewer network. Implementation of GP-RTC on QUC's westerly network was performed in the summer of 1999 and was operational by mid-August. Reductions in overflow volumes with GP-RTC compared to static control are attributed to the optimal use of two existing tunnels as retention facilities as well as the maximal use of the wastewater treatment plant (WWTP) capacity.

Download Full-text

Real-Time Control of Combined Sewer Overflows in Hamilton-Wentworth Region

Water Quality Research Journal ◽

10.2166/wqrj.1997.011 ◽

1997 ◽

Vol 32 (1) ◽

pp. 155-168 ◽

Cited By ~ 4

Author(s):

M. Stirrup ◽

Z. Vitasovic ◽

E. Strand

Keyword(s):

Control System ◽

Real Time ◽

Treatment Plant ◽

Simulation Models ◽

Real Time Control ◽

Combined Sewer Overflows ◽

Hydraulic Simulation ◽

Time Control ◽

Combined Sewer ◽

Sewer Overflows

Abstract The Regional Municipality of Hamilton-Wentworth operates and maintains a large combined sewer system in the Great Lakes basin. During dry weather and small storm events, two large interceptor sewers convey all sanitary and storm flows to the Woodward Avenue wastewater treatment plant. Larger rainfall events, specifically high intensity summer thunderstorms, generate flows which exceed the design capacity of the sanitary interceptors and result in combined sewer overflows to Hamilton Harbour and Cootes Paradise, which ultimately discharge to Lake Ontario. The Region is implementing a comprehensive program for reducing the pollution caused by these overflows. This program includes the construction of several off-line detention storage facilities and the implementation of a real-time control system for combined sewer overflow reduction. Real-time control will enable maximum utilization of the storage available within the combined sewer network and help reduce the frequency and volume of combined sewer overflows. New hydrologic and hydraulic simulation models have been specially developed for this project to help identify, test and implement optimal real-time control strategies. This paper discusses some of the more important aspects related to the design and implementation of the Region’s real-time control system, and focuses mainly on the development of these hydrologic and hydraulic simulation models.

Download Full-text

Advanced Integrated Real-Time Control of Combined Urban Drainage Systems using MPC: Badalona Case Study

10.29007/27gp ◽

2018 ◽

Author(s):

Congcong Sun ◽

Bernat Joseph-Duran ◽

Gabriela Cembrano ◽

Vicenç Puig ◽

Jordi Meseguer

Keyword(s):

Real Time ◽

Wastewater Treatment Plants ◽

Drainage System ◽

Urban Drainage ◽

Real Time Control ◽

Combined Sewer Overflows ◽

Control Approach ◽

Time Control ◽

Sewer Network ◽

First Results

Combined urban drainage system (CUDS) collect both wastewater and raining water through sewer networks to wastewater treatment plants (WWTP) before releasing to the environment. During storm weather, rain and wastewater can overload the capacity of the CUDS and/or the WWTPs, producing combined sewer overflows (CSO). In order to improve the management efficiency of CUDS, advanced real-time control (RTC) of detention and diversion infrastructures in the sewer systems has been proven to contribute to reducing the CSO volumes. This work considers the integrated RTC of sewer network and WWTPs based on model predictive control (MPC) and taking into account the water quality as well as quantity, with the objective of minimizing the environmental impact of CSO on receiving waters. The control approach is validated using a real pilot Badalona sewer network in Spain. The first results, discussion and conclusions are also provided.

Download Full-text

The Importance of Rainfall Distribution in Urban Drainage Operation

Hydrology Research ◽

10.2166/nh.1992.0009 ◽

1992 ◽

Vol 23 (2) ◽

pp. 121-136 ◽

Cited By ~ 2

Author(s):

Fons Nelen ◽

Annemarieke Mooijman ◽

Per Jacobsen

Keyword(s):

Real Time ◽

Treatment Plant ◽

Rain Gauge ◽

Point Of View ◽

Rain Event ◽

Real Time Control ◽

Rainfall Distribution ◽

Statistical Point ◽

Time Control ◽

Spatially Distributed

A control simulation model, called LOCUS, is used to investigate the effects of spatially distributed rain and the possibilities to benefit from this phenomenon by means of real time control. The study is undertaken for a catchment in Copenhagen, where rainfall is measured with a network of 8 rain gauges. Simulation of a single rain event, which is assumed to be homogeneous, i.e. using one rain gauge for the whole catchment, leads to large over- and underestimates of the systems output variables. Therefore, when analyzing a single event the highest possible degree of rainfall information may be desired. Time-series simulations are performed for both an uncontrolled and a controlled system. It is shown that from a statistical point of view, rainfall distribution is NOT significant concerning the probability of occurrence of an overflow. The main contributing factor to the potential of real time control, concerning minimizing overflows, is to be found in the system itself, i.e. the distribution of available storage and discharge capacity. When other operational objectives are involved, e.g., to minimize peak flows to the treatment plant, rainfall distribution may be an important factor.

Download Full-text

Optimisation and control of the inflow to a wastewater treatment plant using integrated modelling tools

Water Science & Technology ◽

10.2166/wst.1998.0083 ◽

1998 ◽

Vol 37 (1) ◽

pp. 347-354 ◽

Cited By ~ 2

Author(s):

Ole Mark ◽

Claes Hernebring ◽

Peter Magnusson

Keyword(s):

Wastewater Treatment ◽

Real Time ◽

Wastewater Treatment Plant ◽

Treatment Plant ◽

Pilot Project ◽

Integrated Modelling ◽

Real Time Control ◽

Sewer System ◽

Time Control ◽

The Impact

The present paper describes the Helsingborg Pilot Project, a part of the Technology Validation Project: “Integrated Wastewater” (TVP) under the EU Innovation Programme. The objective of the Helsingborg Pilot Project is to demonstrate implementation of integrated tools for the simulation of the sewer system and the wastewater treatment plant (WWTP), both in the analyses and the operational phases. The paper deals with the programme for investigating the impact of real time control (RTC) on the performance of the sewer system and wastewater treatment plant. As the project still is in a very early phase, this paper focuses on the modelling of the transport of pollutants and the evaluation of the effect on the sediment deposition pattern from the implementation of real time control in the sewer system.

Download Full-text

Feasibility Study on the Real-time Control System of the Pumps for the Reduction of Combined Sewer Overflows

Proceedings of the Water Environment Federation ◽

10.2175/193864702784249114 ◽

2002 ◽

Vol 2002 (17) ◽

pp. 447-463

Author(s):

T. Sugita ◽

M. Kurozumi ◽

H. Ohashi ◽

H. Mizushima

Keyword(s):

Control System ◽

Real Time ◽

Feasibility Study ◽

Real Time Control ◽

Combined Sewer Overflows ◽

The Real ◽

Time Control ◽

Combined Sewer ◽

Sewer Overflows

Download Full-text

Effects of real time control of sewer systems on treatment plant performance and receiving water quality

Water Science & Technology ◽

10.2166/wst.2002.0083 ◽

2002 ◽

Vol 45 (3) ◽

pp. 229-237 ◽

Cited By ~ 2

Author(s):

T. Frehmann ◽

A. Niemann ◽

P. Ustohal ◽

W.F. Geiger

Keyword(s):

Real Time ◽

Treatment Plant ◽

Drainage System ◽

Control Measures ◽

Plant Performance ◽

Integral Model ◽

Real Time Control ◽

Time Control ◽

The Impact ◽

Receiving Water

Four individual mathematical submodels simulating different subsystems of urban drainage were intercoupled to an integral model. The submodels (for surface runoff, flow in sewer system, wastewater treatment plant and receiving water) were calibrated on the basis of field data measured in an existing urban catchment investigation. Three different strategies for controlling the discharge in the sewer network were defined and implemented in the integral model. The impact of these control measures was quantified by representative immission state-parameters of the receiving water. The results reveal that the effect of a control measure may be ambivalent, depending on the referred component of a complex drainage system. Furthermore, it is demonstrated that the drainage system in the catchment investigation can be considerably optimised towards environmental protection and operation efficiency if an appropriate real time control on the integral scale is applied.

Download Full-text

Modelling real-time control of WWTP influent flow under data scarcity

Water Science & Technology ◽

10.2166/wst.2015.641 ◽

2015 ◽

Vol 73 (7) ◽

pp. 1637-1643 ◽

Cited By ~ 10

Author(s):

Stefan Kroll ◽

Geert Dirckx ◽

Brecht M. R. Donckels ◽

Mieke Van Dorpe ◽

Marjoleine Weemaes ◽

...

Keyword(s):

Real Time ◽

Treatment Plant ◽

Added Value ◽

Minor Role ◽

Real Time Control ◽

Time Control ◽

Spatial System ◽

System Properties ◽

Secondary Settling ◽

A Minor

In order to comply with effluent standards, wastewater operators need to avoid hydraulic overloading of the wastewater treatment plant (WWTP), as this can result in the washout of activated sludge from secondary settling tanks. Hydraulic overloading can occur in a systematic way, for instance when sewer network connections are extended without increasing the WWTP's capacity accordingly. This study demonstrates the use of rule-based real-time control (RTC) to reduce the load to the WWTP while restricting the overall overflow volume of the sewer system to a minimum. Further, it shows the added value of RTC despite the limited availability of monitoring data and information on the catchment through a parsimonious simulation approach, using relocation of spatial system boundaries and creating required input data through reverse modelling. Focus was hereby on the accurate modelling of pump hydraulics and control. Finally, two different methods of global sensitivity analysis were employed to verify the influence of parameters of both the model and the implemented control algorithm. Both methods show the importance of good knowledge of the system properties, but that monitoring errors play a minor role.

Download Full-text

Astlingen – a benchmark for real time control (RTC)

Water Science & Technology ◽

10.2166/wst.2018.172 ◽

2018 ◽

Vol 2017 (2) ◽

pp. 552-560 ◽

Cited By ~ 5

Author(s):

Manfred Schütze ◽

Maja Lange ◽

Michael Pabst ◽

Ulrich Haas

Keyword(s):

Real Time ◽

Preliminary Analysis ◽

Control Strategies ◽

Treatment Plant ◽

Drainage System ◽

Real Time Control ◽

Sewer System ◽

Time Control ◽

System 2 ◽

Water Association

Abstract This contribution serves two purposes. (1) It presents an updated version of the Astlingen example developed by the working group ‘Integral Real Time Control’ of the German Water Association (DWA), which serves as a benchmark example for the setup and evaluation of real time control strategies. As this benchmark is also intended for educational use, it demonstrates a simple RTC algorithm, illustrating the main concepts of RTC of drainage system. (2) The paper also encourages the preliminary analysis of the potential feasibility and benefit of a temporal increase of inflow to the wastewater treatment plant (WWTP) before analysing the WWTP behaviour in detail. For the present example, RTC within the sewer system alone led to almost the same reduction of overflow volume as permitting the inflow to the WWTP to be increased for 6 h within any 24 h, if at all permitted.

Download Full-text