Alex Van der Helm

The operation of smart wastewater treatment plants (WWTPs) is increasingly paramount in improving effluent quality, facilitating resource recovery and reducing carbon emissions. To achieve these objectives, sensors, monitoring systems, and artificial intelligence (AI)-based models are increasingly being developed and utilised for decision support a...

Typically, within the context of treatment plant-wide data, the quality of data can be impacted by sensor faults, sensor calibration issues, fouling of and obstruction to the sensors and connectivity problems between sensors, actuators and the data management system, therefore hampering advanced data driven monitoring and control of (critical) wate...

Although water quality has extensively improved over the last decade, recreational uses of the canal network in Amsterdam are limited by variations in water quality associated with stormwater runoff and episodic harmful algal blooms. The current systems for monitoring water quality are based on a stationary network of sampling points, offline testi...

As of the beginning of 2017, more than four years after opening, Zaatari refugee camp in the Hashemite Kingdom of Jordan hosts around 80,000 Syrian refugees. Zaatari is one of the largest refugee camps in the world, in one of the most water scarce countries. Since its establishment, drinking water has been trucked to communal facilities. Wastewater...

The application of ozone in water treatment serves many purposes, such as disinfection and degradation of organic micro-pollutants. To optimise the applied ozone dosage by on-line control, real-time information on the actual Ct value, the bromate and assimilable organic carbon concentration (AOC) is necessary. With UV/Vis spectroscopy, algorithms h...

Softening at drinking water treatment plants is often realised by fluidised bed pellet reactors. Generally, sand is used as seeding material and pellets are produced as a by-product. To improve to sustainability, research has been carried out to replace the seeding material by re-using grained and sieved calcite pellets as seeding material. An expl...

In practice, drinking water technologists use simplified calculation methods for aquatic chemistry calculations. Recently, the database stimela.dat is developed especially for aquatic chemistry for drinking water treatment processes. The database is used in PHREEQC, the standard in geohydrology for calculating chemical equilibria in groundwater. Th...

http://www.drink-water-eng-sci.net/6/115/2013/dwes-6-115-2013.html The new German standard on the calculation of calcite saturation in drinking water, DIN 38404-10, 2012 (DIN), marks a change in drinking water standardization from using simplified equations applicable for nomographs and simple calculators to using extensive chemical modeling requi...

This research deals with the contribution of process simulation models to the factory acceptance test (FAT) of process automation (PA) software of drinking water treatment plants. Two test teams tested the same piece of modified PA-software. One team used an advanced virtual commissioning (AVC) system consisting of PA-emulation and integrated proce...

The new German standard for calcium carbonate saturation in drinking water, DIN 38404-10, 2012 (DIN), marks a change in drinking water standardization from using simplified equations applicable for nomographs and simple calculators to using extensive chemical modeling requiring computer programs. The standard specifies the chemical outlines for the...

Waternet, the water cycle company of Amsterdam and surrounding areas, uses the life cycle assessment (LCA) method to evaluate the environmental impact of investment decisions and to determine the potential reduction of direct and indirect greenhouse gas (GHG) emissions of different alternatives. This approach enables Waternet to fulfil its corporat...

Waterspot is a plant-wide drinking water treatment simulator that has been developed in a 3 year research project. The incorporation of real-time and historical data of on-line water quality measurements, flow measurements, process data and water quality laboratory measurements in the simulator improves the acceptance of model output by technologis...

An inventory is made of the possibilities to recover sustainable energy from the water cycle by identifying different water flows in a municipal environment as a sustainable energy source. It is discussed what role public water utilities should play in the market of energy from water. This is done for Waternet, the public water utility of Amsterdam...

Good modelling practice increases the credibility and impact of the information and insight that modelling aims to generate. It is known to be crucial for model acceptance and it is a necessity to amass a long-term, systematic thorough knowledge base for both science and decision making. This paper shows how ten steps in model development and evalu...

Water supply companies are gradually changing to a centralised, fully automated operation. The drivers for this change are the increase in efficiency and a better and more stable water quality. Fully automated treatment plants will require more sophisticated operator care than manually operated plants, so operation supervisors should periodically t...

The objective of this study was to evaluate the effects of the character and the removal of natural organic matter (NOM) on the formation of assimilable organic carbon (AOC) and bromate during ozone disinfection. Natural waters from two locations with different dissolved organic carbon (DOC) concentrations were tested. In addition, the DOC concentr...

In general, the available control actions in drinking water treatment plants are not directly related to the process objectives for water quality. Model based optimization of operation of a drinking water treatment plant by direct control of water quality objectives is discussed. Plant control with PID controllers is embedded in the model of a drin...

Ozonation experiments (2.5-5 m(3)h(-1)) were performed by dosing dissolved ozone in a continuous flow pilot-scale contactor consisting of a pipe with plug flow reactor (PFR) characteristics. In the PFR ozone, E. coli, bromate and AOC concentrations were measured from 1.3 to 1,460 seconds retention time during ozonation of natural water. The experim...

Optimization for operation of drinking water treatment plants should focus on water quality and not on environmental impact or costs. Using improvement of water quality as objective for optimization can lead to new views on operation, design and concept of drinking water treatment plants. This is illustrated for ozonation in combination with biolog...

Major emphasis must be laid on guaranteeing high standards in drinking water quality. This can only be achieved when the drinking water treatment plant operates optimally. In this paper a treatment plant, consisting of ozonation with low dosage of ozone, pellet softening, pH correction and activated carbon filtration, treating lake water with high...

In this research, the environmental and financial impact of the existing water treatment—i.e. the drinking water production plant Weesperkarspel and its pre-treatment plant Loenderveen—are determined as a reference for future changes and for assessing opportunities for the reduction of the environmental impact.Environmental impact for Loenderveen a...

Waternet (formerly Amsterdam Water Supply) has been seeking a sustainable scenario for producing drinking water and offering services that fulfill the requirements of clients and regulations, and, at the same time, maintains a sound environmental performance while keeping costs as low as possible. Presently, the company is in the process of evaluat...

The concentrations of dissolved ozone and assimilable organic carbon (AOC) are important performance parameters in drinking water production. For the measurement of ozone, a spectral algorithm was developed that allows quantification in situ using a UV/Vis spectrometer probe. Furthermore, a strong correlation between the change in the absorption sp...

Experimental research was carried out for calibration and validation of a model describing ozone decay and ozone exposure (CT), decrease in UV absorbance at 254 nm (UVA254), increase in assimilable organic carbon concentration and bromate formation. The model proved to be able to predict these parameters on the basis of the applied ozone dosage. Th...

The concentration of dissolved ozone and Assimilable Organic Carbon (AOC) are important performance parameters in drinking water production. For the measurement of ozone, a spectral algorithm was developed that allows quantification insitu using a UV/Vis spectrometer probe. Furthermore, a strong correlation between the change in the absorption spec...

To determine the disinfection efficacy of ozonation, water companies can apply several disinfection calculation methods. The goal of this study was to evaluate the use of the T10 and continuous stirred tank reactor (CSTR) method to extrapolate inactivation rates of ozone sensitive microorganisms observed in laboratory tests to full-scale ozonation...

Bromate formation experiments were carried out in a 100 l/h bench-scale dissolved ozone plug flow reactor (DOPFR) with natural filtered water from the drinking water treatment plant Leiduin of Amsterdam Water Supply at gross ozone dosages of 0.7–3.4 mg/l. In the DOPFR, ozone is dosed by intensively mixing a dissolved ozone water flow (side stream)...

Waterleidingbedrijf Amsterdam wil in de toekomst een verdere verbetering van haar waterkwaliteit realiseren. Daarvoor zal een integrale benadering van het zuiveringsproces noodzakelijk zijn. Processturing zal daarbij plaatsvinden op basis van een integraal sturingsmodel van de zuivering. In het kader van Promocit (PROces Modelling and Intelligent C...

Drinking water production plants (in The Netherlands) are normally controlled by effluent quality. When the effluent quality does not meet the guidelines, the treatment process is manipulated. This is mainly done using the experience of the operators. Water quality models can be used to support the operators' task by off-line process evaluation and...

Drinking water treatment plants automation becomes more sophisticated, more on-line monitoring systems become available and integration of modeling environments with control systems becomes easier. This gives possibilities for model-based optimization. In operation of drinking water treatment plants, the processes are usually optimized individually...