- document
-
van der Hoek, J.P. (author), Deng, Tianyi (author), Spit, Tiza (author), Luimstra, Veerle (author), de Kreuk, M.K. (author), van Halem, D. (author)Organic micropollutants (OMPs) enter the aquatic environment via municipal wastewater treatment plants (WWTPs). As conventional WWTPs have limited capacity for the removal of OMPs, additional processes are required, like ozone - granular activated carbon (GAC) filtration. A specific lay-out of this process is the O3-STEP® process, in which the...journal article 2024
- document
-
Kraaijeveld, E. (author), Rijsdijk, S. (author), van der Poel, S. (author), van der Hoek, J.P. (author), Rabaey, K. (author), van Halem, D. (author)The mechanisms and by-product formation of electrochemical oxidation (EO) for As(III) oxidation in drinking water treatment using groundwater was investigated. Experiments were carried out using a flowthrough system, with an RuO <sub>2</sub>/IrO <sub>2</sub> MMO Ti anode electrode, fed with synthetic and natural groundwater containing As(III)...journal article 2024
- document
-
Roy, M. (author), Kraaijeveld, E. (author), Gude, J.C.J. (author), van Genuchten, Case M. (author), Rietveld, L.C. (author), van Halem, D. (author)Long-term consumption of groundwater containing elevated levels of arsenic (As) can have severe health consequences, including cancer. To effectively remove As, conventional treatment technologies require expensive chemical oxidants to oxidise neutral arsenite (As(III)) in groundwater to negatively charged arsenate (As(V)), which is more...journal article 2024
- document
-
Trikannad, S.A. (author), Attiani, Valentina (author), van der Wielen, Paul W.J.J. (author), Smidt, Hauke (author), van der Hoek, J.P. (author), van Halem, D. (author)Slow sand filters (SSFs) are widely used in drinking water production to improve microbial safety and biological stability of water. Full-scale SSFs are maintained by scraping the biomass-rich top layers of sand. The period of downtime required for filter recovery after scraping is a major challenge due to limited knowledge of the re...journal article 2024
- document
-
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
- document
-
Trikannad, S.A. (author), van Halem, D. (author), Foppen, J.W.A. (author), van der Hoek, J.P. (author)Slow Sand Filtration is popular in drinking water treatment for the removal of a wide range of contaminants (e.g., particles, organic matter, and microorganisms). The Schmutzdecke in slow sand filters (SSFs) is known to be essential for pathogen removal, however, this layer is also responsible for increased head loss. Since the role of deeper...journal article 2023
- document
-
Wang, K. (author), Holm, P. E. (author), Trettenes, U. Brinkmann (author), Bandaru, S. R.S. (author), van Halem, D. (author), van Genuchten, C. M. (author)Iron (Fe)-based treatment methods are widely applied to remove carcinogenic arsenic (As) from drinking water, but generate toxic As-laden Fe (oxyhydr)oxide waste that has traditionally been ignored for resource recovery by the water sector. However, the European Commission recently classified As as a Critical Raw Material (CRM), thus...journal article 2023
- document
-
Corbera Rubio, F. (author), Laureni, M. (author), Koudijs, N. (author), Müller, S. (author), van Alen, Theo (author), Schoonenberg, Frank (author), Lücker, Sebastian (author), Pabst, Martin (author), van Loosdrecht, Mark C.M. (author), van Halem, D. (author)Rapid sand filters (RSF) are an established and widely applied technology for groundwater treatment. Yet, the underlying interwoven biological and physical-chemical reactions controlling the sequential removal of iron, ammonia and manganese remain poorly understood. To resolve the contribution and interactions between the individual reactions...journal article 2023
- document
-
Annaduzzaman, M. (author), Rietveld, L.C. (author), Hoque, Bilqis Amin (author), van Halem, D. (author)Sequential iron (as Fe<sup>2+</sup>) oxidation has been found to yield improved arsenic (as As(III)) uptake than the single-step oxidation. The objective of this study was to gain a better understanding of interactions with phosphate (PO<sub>4</sub><sup>3−</sup>) and silicate (SiO<sub>4</sub><sup>2−</sup>) during sequential Fe<sup>2+</sup>...journal article 2022
- document
-
Roy, M. (author), van Genuchten, Case M. (author), Rietveld, L.C. (author), van Halem, D. (author)Groundwater contaminated with arsenic (As) must be treated prior to drinking, as human exposure to As at toxic levels can cause various diseases including cancer. Conventional aeration-filtration applied to anaerobic arsenite (As(III)) contaminated groundwater can remove As(III) by co-oxidizing native iron (Fe(II)) and As(III) with oxygen (O...journal article 2022
- document
-
Bicudo, Bruno (author), Van Der Werff, Bart Jan (author), Medema, G.J. (author), van Halem, D. (author)Electrochemical water treatment is gaining increasing popularity due to its wide range of potential applications, its decreasing costs, and its suitability as a decentralized treatment alternative, but mainly due to it being considered a "green technology". In the field of municipal wastewater treatment, the use of iron electrocoagulation (Fe...journal article 2022
- document
-
Spit, T.P.M. (author), van der Hoek, J.P. (author), de Jong, Coen (author), van Halem, D. (author), de Kreuk, M.K. (author), Bicudo, Bruno (author)At wastewater treatment plants (WWTPs), additional steps are introduced for removal of organic micropollutants (OMPs) from the treated effluents, especially pharmaceutical residues. At the same time, a new concern is emerging: antibiotic resistance (AR). This research studied the effect of ozonation, coagulation and granular activated carbon ...journal article 2022
- document
-
Goedhart, R.C. (author), Müller, S. (author), van Loosdrecht, Mark C.M. (author), van Halem, D. (author)Iron in anaerobic groundwater is commonly removed by oxidation followed by sand filtration. This produces large volumes of iron(III)(hydr)oxide sludge with little value. Our research investigates the novel concept of anaerobic iron(II) recovery from groundwater as the valuable mineral vivianite (Fe<sub>3</sub>(PO<sub>4</sub>)<sub>2</sub> • 8...journal article 2022
- document
-
Bicudo, Bruno (author), Medema, G.J. (author), van Halem, D. (author)Electrochemical ferrous iron (Fe<sup>2+</sup>) wastewater treatment is gaining momentum for treating municipal wastewater due to its decreasing costs, environmental friendliness and capacity for removal of a wide range of contaminants. Disinfection by iron electrocoagulation (Fe-EC) has been occasionally reported in full scale industrial...journal article 2022
- document
-
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<sup>−</sup>) from groundwater sources. Ca-Al-CO<sub>3</sub> layered double hydroxides (LDHs) have shown promising defluoridation efficiency; however, defluoridation by Ca-Al-CO<sub>3</sub> LDHs is highly pH sensitive. This study showed that simultaneous...journal article 2021
- document
-
Annaduzzaman, M. (author), Rietveld, L.C. (author), Ghosh, D. (author), Hoque, Bilqis A. (author), van Halem, D. (author)Storage containers are usually used to provide a constant water head in decentralized, community groundwater treatment systems for the removal of iron (Fe) and arsenic (As). However, the commonly practiced aeration prior to storage assists in rapid and complete Fe<sup>2+</sup> oxidation, resulting in poor As removal, despite sufficient native...journal article 2021
- document
-
Wei, L. (author), Li, Z. (author), Ye, G. (author), Rietveld, L.C. (author), van Halem, D. (author)Excessive F<sup>-</sup> in drinking water due to natural and anthropogenic activities is a serious health hazard affecting humans worldwide. In this study, a comparative assessment was made of eight mineral-based materials with advantageous structural properties for F<sup>-</sup> uptake: layered-double-hydroxides (LDHs), geopolymers,...journal article 2021
- document
-
Bicudo, Bruno (author), van Halem, D. (author), Trikannad, S.A. (author), Ferrero, Giuliana (author), Medema, G.J. (author)In this paper we analyse the feasibility of low voltage iron electrocoagulation as a means of municipal secondary effluent treatment with a focus on removal of microbial indicators, Antibiotic Resistant Bacteria (ARB) and nutrients. A laboratory scale batch unit equipped with iron electrodes was used on synthetic and real secondary effluent...journal article 2021
- document
-
Roy, M. (author), van Genuchten, Case M. (author), Rietveld, L.C. (author), van Halem, D. (author)Arsenic (As) is a toxic element present in many (ground)water sources in the world. Most conventional As removal techniques require pre-oxidation of the neutral arsenite (As(III)) species to the negatively charged arsenate (As(V)) oxyanion to optimize As removal and minimize chemical use. In this work, a novel, continuous-flow As removal...journal article 2021
- document
-
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 (Fe<sup>2+</sup>) oxidation to Fe<sup>3+</sup> and precipitation as Fe<sup>3+</sup>-(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