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DOC and Ammonium Removal Processes in Slow Sand FIlters - Influence of Grain Size and Flow Rate

Huang, Yuwei (author)

Slow sand filters (SSFs) are essential for ensuring microbial quality and biological stability of drinking water in the Netherlands. However, gaps exist in understanding of removal processes of dissolved organic carbon (DOC) and ammonium and the effects of grain size, loading rate, and backwashing on removal in SSFs.<br/>Four lab-scale SSF...

master thesis 2023

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Microbiome, resistome and mobilome of chlorine-free drinking water treatment systems

Calderon Franco, D. (author), Corbera Rubio, F. (author), Cuesta Sanz, M. (author), Pieterse, Brent (author), de Ridder, David (author), van Loosdrecht, Mark C.M. (author), van Halem, D. (author), Laureni, M. (author), Weissbrodt, D.G. (author)

Drinking water treatment plants (DWTPs) are designed to remove physical, chemical, and biological contaminants. However, until recently, the role of DWTPs in minimizing the cycling of antibiotic resistance determinants has got limited attention. In particular, the risk of selecting antibiotic-resistant bacteria (ARB) is largely overlooked in...

journal article 2023

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One-Step Reverse Osmosis Based on Riverbank Filtration for Future Drinking Water Purification

Zhai, Yujia (author), Liu, G. (author), van der Meer, Walter G.J. (author)

The presence of newly emerging pollutants in the aquatic environment poses great challenges for drinking water treatment plants. Due to their low concentrations and unknown characteristics, emerging pollutants cannot be efficiently removed by conventional water treatment processes, making technically, economically, and environmentally...

journal article 2022

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Hydraulic modelling of liquid-solid fluidisation in drinking water treatment processes

Kramer, O.J.I. (author)

In drinking water treatment plants, multiphase flows are a frequent phenomenon. Examples of such flows are pellet-softening and filter backwashing where liquid-solid fluidisation is applied. A better grasp of these fluidisation processes is needed to be able to determine optimal hydraulic states. In this research, models were developed, and...

doctoral thesis 2021

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Genomic profiles and removal mechanisms explain the observed stratification of Fe²⁺, NH₄⁺ and Mn²⁺ removal in rapid sand filters

Koudijs, Nienke (author)

Groundwater is an excellent source for the production of drinking water due to its low concentration of microorganisms and contaminants. The main contaminants present in groundwater are iron, ammonium and manganese, which are sequentially removed in rapid sand filters by a combination of biological and chemical processes. Currently, limited...

master thesis 2021

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Fluoride removal from water by Ca-Al-CO₃ layered double hydroxides and simultaneous acidification

Wei, L. (author), Zietzschmann, F.E. (author), Rietveld, L.C. (author), van Halem, D. (author)

Millions of people worldwide are exposed to excessive concentrations of fluoride (F⁻) from groundwater sources. Ca-Al-CO₃ layered double hydroxides (LDHs) have shown promising defluoridation efficiency; however, defluoridation by Ca-Al-CO₃ LDHs is highly pH sensitive. This study showed that simultaneous...

journal article 2021

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Fluidisation characteristics of granular activated carbon in drinking water treatment applications

Kramer, O.J.I. (author), van Schaik, C. (author), Dacomba Torres, P.D.R. (author), de Moel, P.J. (author), Boek, E.S. (author), Baars, E.T. (author), Padding, J.T. (author), van der Hoek, J.P. (author)

Granular activated carbon (GAC) filtration is an important unit operation in drinking water treatment. GAC filtration is widely used for its filtration and adsorption capabilities as a barrier for undesired organic macro- and micro-pollutants. GAC filtration consists of two successive phases: adsorption and filtration, capturing the impurities...

journal article 2021

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Arsenic removal from iron-containing groundwater by delayed aeration in dual-media sand filters

Annaduzzaman, M. (author), Rietveld, L.C. (author), Amin Hoque, Bilqis (author), Bari, Md Niamul (author), van Halem, D. (author)

Generally, abstracted groundwater is aerated, leading to iron (Fe²⁺) oxidation to Fe³⁺ and precipitation as Fe³⁺-(hydr)oxide (HFO) flocs. This practice of passive groundwater treatment, however, is not considered a barrier for arsenic (As), as removal efficiencies vary widely (15–95%), depending on Fe/As ratio...

journal article 2021

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New hydraulic insights into rapid sand filter bed backwashing using the Carman–Kozeny model

Kramer, O.J.I. (author), de Moel, P.J. (author), Padding, J.T. (author), Baars, Eric T. (author), Rutten, Sam B. (author), Elarbab, Awad H.E. (author), Hooft, Jos F.M. (author), Boek, Edo S. (author), van der Hoek, J.P. (author)

Fluid flow through a bed of solid particles is an important process that occurs in full-scale water treatment operations. The Carman–Kozeny model remains highly popular for estimating the resistance across the bed. It is common practice to use particle shape factors in fixed bed state to match the predicted drag coefficient with experimentally...

journal article 2021

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Quantification and modelling of organic micropollutant removal by reverse osmosis (RO) drinking water treatment

Ebrahimzadeh, S. (author), Wols, Bas (author), Azzellino, Arianna (author), Martijn, Bram J. (author), van der Hoek, J.P. (author)

Reverse osmosis (RO) is the most promising membrane technology in organic micropollutants (MPs) removal of drinking water treatment. For 78 MPs, passage and removal were evaluated with an ESPA3 RO membrane and the robustness of RO against MPs was studied. The MPs were classified according to their charge and hydrophobicity. The results showed...

review 2021

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Experimental and numerical insights into heterogeneous liquid-solid behaviour in drinking water softening reactors

Nijssen, T.M.J. (author), Kramer, O.J.I. (author), de Moel, P.J. (author), Rahman, J. (author), Kroon, J.P. (author), Berhanu, P. (author), Boek, E.S. (author), van der Hoek, J.P. (author), Padding, J.T. (author)

Liquid-solid fluidisation is frequently encountered in drinking water treatment processes, for instance in seeded crystallisation softening processes. For modest superficial fluid velocities, liquid–solid fluidisation systems are generally considered to be homogeneous, as reported in literature. However, during fluidisation experiments with...

journal article 2021

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A novel sensor measuring local voidage profile inside a fluidised bed reactor

Kramer, O.J.I. (author), van Schaik, C. (author), Hangelbroek, J.J. (author), de Moel, P.J. (author), Colin, M.G. (author), Amsing, M. (author), Boek, E.S. (author), Breugem, W.P. (author), Padding, J.T. (author), van der Hoek, J.P. (author)

Liquid-solid fluidisation is frequently encountered in drinking water treatment processes, often to obtain a large liquid-solid interfacial surface area. A large surface area is crucial for optimal seeded crystallisation in full-scale softening reactors. Due to crystallisation, particles grow and migrate to a lower zone in the reactor which...

journal article 2021

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Monitoring the characteristics and removal of natural organic matter fractions in selected south african water treatment plants

Moyo, Welldone (author), Chaukura, Nhamo (author), Motsa, Machawe M. (author), Msagati, Titus A.M. (author), Mamba, Bhekie B. (author), Heijman, Sebastiaan (author), Nkambule, Thabo T.I. (author)

This study used spectroscopic methods to investigate the fate and dynamics of natural organic matter (NOM) as it traverses the treatment train at three water treatment plants (WTPs) in South Africa. The character, quantity, and removability of NOM at specific treatment stages was investigated by measuring changes in dissolved organic carbon ...

journal article 2020

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Accurate voidage prediction in fluidisation systems for full-scale drinking water pellet softening reactors using data driven models

Kramer, O.J.I. (author), de Moel, P.J. (author), Padding, J.T. (author), Baars, E.T. (author), El Hasadi, Yousef M.F. (author), Boek, E.S. (author), van der Hoek, J.P. (author)

In full-scale drinking water production plants in the Netherlands, central softening is widely used for reasons related to public health, client comfort, and economic and environmental benefits. Almost 500 million cubic meters of water is softened annually through seeded crystallisation in fluidised bed reactors. The societal call for a circular...

journal article 2020

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Fluidization behavior of granular activated carbon: For drinking water treatment applications

Dacomba Torres, Pablo (author)

For drinking water treatment applications, it is possible to predict the external porosity of an expanded bed of granular activated carbon in fluidized conditions. A new model has been developed with a 2% relative prediction error. <br/><br/>In order to supply sufficient and safe drinking water, water utilities use a treatment train consisting...

master thesis 2019

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The properties and removal efficacies of natural organic matter fractions by South African drinking water treatment plants

Moyo, Welldone (author), Chaukura, Nhamo (author), Msagati, Titus A.M. (author), Mamba, Bhekie B. (author), Heijman, Sebastiaan (author), Nkambule, Thabo T.I. (author)

This study presents an investigation on the fate of natural organic matter (NOM) and its dynamics throughout the treatment train at various drinking water treatment plants (WTP) in South Africa. The characteristics, concentration and removal efficiencies of NOM at various treatment stages on the basis of dissolved organic carbon, UV...

journal article 2019

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Bromate reduction by iron(II) during managed aquifer recharge: A laboratory-scale study

Wang, F. (author), Salgado Ismodes, V.A. (author), van der Hoek, J.P. (author), van Halem, D. (author)

The removal of bromate (BrO₃ ^-) as a byproduct of ozonation in subsequent managed aquifer recharge (MAR) systems has so far gained little attention. This preliminary study with anoxic batch experiments was executed to explore the feasibility of chemical BrO₃ ^- reduction in Fe-reducing zones of MAR...

journal article 2018

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Decision support for water quality management of contaminants of emerging concern

Fischer, A. (author), ter Laak, T (author), Bronders, J. (author), Desmet, N. (author), Christoffels, E. (author), van Wezel, A (author), van der Hoek, J.P. (author)

Water authorities and drinking water companies are challenged with the question if, where and how to abate contaminants of emerging concern in the urban water cycle. The most effective strategy under given conditions is often unclear to these stakeholders as it requires insight into several aspects of the contaminants such as sources, properties...

journal article 2017

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Preliminary Study of PDAM Tirtawening Water Treatment Plant, Bandung, Indonesia for Sustainable Production Capacity

Fausta, N. (author), Okumura, N. (author), Salgado Ismodes, V. (author), Speksnijder, R. (author)

In this study, the raw water intake, transmission pipeline and the PDAM Badaksinga Treatment Plant in the city of Bandung in West Java, Indonesia was researched in order to evaluate the increase of capacity of Treatment Plant in order to satisfy the water demand of the citizens of Bandung. For this purpose water quality and flow measurements...

student report 2016

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Plant wide chemical water stability modelling with PHREEQC for drinking water treatment

Van der Helm, A.W.C. (author), Kramer, O.J.I. (author), Hooft, J.F.M. (author), De Moel, P.J. (author)

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....

conference paper 2015