Performance improvement of wastewater transport systems and treatment processes by advanced monitoring and predictive control
Icke, O.1, Lubbers, C.1, van Eijden, R.1, de Koning, M.1, Huising, C.2 and de Wit, R.3, 1Royal HaskoningDHV, 2Water authority Vallei en Veluwe, The Netherlands, 3Water board Limburg, The Netherlands
(free)
Abstract
Water authorities aim to operate the wastewater transport and treatment systems as cost-effectively
as possible. Asset control, based on accurate predictions, is a proven way to optimise wastewater
processes. This requires accurate information and data on the assets, how they perform and the
ability to change operations to optimise required processes. The often fouled state and inherent
unsteady behaviour of transport systems yield a technical challenge analysing and controlling these
systems. Methods, based on real-time data for advanced monitoring and predictive control of
wastewater transport systems, have been developed. This paper demonstrates in two case studies
that performance monitoring and predictive control was successfully implemented. One case study
describes an application of an advanced performance monitoring system. Performance indicators are
defined and derived from real-time measurements in combination with hydraulic numerical model
simulations. Results show that condition-based maintenance and performance predictions are
possible. Another case study describes an application of a predictive controller using rainfall and dryweather flow predictions. Predictive control reduced peak discharges to the wastewater treatment
plant by 58% using the available storage of the sewerage without extra combined sewer overflow. It
improved the performance of the treatment processes and increased the utilisation of the posttreatment phase.
Keywords
Asset management, digital twin, dry-weather flow prediction, optimisation of existing assets,
performance monitoring, predictive control, rainfall forecast, wastewater transport.
Introduction
The corporate aim of water authorities is to operate the wastewater systems as efficiently as possible
with minimal costs while meeting all required goals. These goals include minimising combined sewer
overflows (CSO), minimising energy costs / carbon emissions, predictive condition-based
maintenance and improving effluent quality of the wastewater treatment plant (WwTP).
A challenge many water authorities face realising these goals is the lack of information on the
performance of the system and as a consequence the insight to control the processes to realise the
goals. Normal operation of the pumping station is based on the local sump level prescribing the flow
rate of the pump. This often leads to unnecessary large dynamics in the flow rate, which is detrimental to treatment processes and energy consumption. Altering pump deployment is an effective way to realise calm networks and as a result the mentioned goals.
