Nieuwsbrief Sanitary Engineering

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1 Nieuwsbrief Sanitary Engineering Uitgave: TU-Delft Faculteit CiTG sectie Sanitary Engineering Redactie: Mieke Hubert Luuk Rietveld Bouke Kooreman Contact: Postbus GA Delft +31(0) Internet: Nummer: 12 e jaargang nummer 5 oktober 2012 Redactie De afgelopen tijd heb ik mij weer eens begeven in het Afrikaanse om daar twee weken lang les te geven aan Mozambikaanse Bachelor studenten. Wij hebben daar samen met UNESCO-IHE, IRC, NHL en Vitens Evides International een project om een programma op te zetten voor Water en Sanitatie onderwijs (en onderzoek). Mijn filosofie is dat onderwijs in Afrika het allerbelangrijkste is voor ontwikkeling. Met goed opgeleide mensen kan de samenleving dan zelf de infrastructuur op orde brengen. De opzet is dat de studenten twee weken intensief theorielessen krijgen (8 uur per dag) en daarna, gedurende zes weken, een praktisch project doen, waarbij ze de theorie in de praktijk moeten brengen. Het is fantastisch om te zien hoe gemotiveerd de studenten zijn. Hun achtergrond is op sommige punten belabberd. Zo hadden ze nog geen vloeistofmechanica gehad en wisten ze niet wat het concept druk betekent ( hoe kan het dan dat het water door een leiding weer naar boven stroomt? ). Na een paar weken waren ze (gelukkig) een stuk opgeschoten en snapten ze waarom er soms geen water uit de kraan komt, wat de gevolgen zijn van het uitzetten van de beluchting in de waterzuivering en waarom het water in de stad naar ijzer smaakt. Op dit moment zijn ze aan het uitvogelen hoeveel water er verdwijnt omdat het simpelweg niet wordt afgerekend. Ik hoop dat we met deze studenten weer een nieuwe generatie kunnen opleiden die Mozambique verder kan brengen. Hierbij hoort natuurlijk niet alleen de inhoud, maar ook de teamsfeer en de gezelligheid. Hoe leg je uit in het Portugees wat de VrijMiBo is? Wat is het verschil tussen Mozambikaanse studenten en Delftse studenten dan opeens weer klein. Wat is het leuk om bij terugkomst te zien dat, in het kader van het lustrum van de TU Delft, de Eerste Nederlandse Studenten Fitterijwedstrijden werden gehouden. In eerste instantie was men wat gereserveerd, maar na afloop verklaarde het dispuut dat dit ECHT een jaarlijkse activiteit moet worden!! Hulde aan KWN en de fitterijcommissie om zo weer een stukje dichter bij onze studenten te staan. Er zijn er tenslotte wel (weer) genoeg. We hebben weer verschillende afstudeerders, zie hiervoor de aankondigingen in de nieuwsbrief. Het zijn aansprekende onderwerpen, waarbij vooral de toename van het aantal afstudeerders op het gebied van Urban Drainage opvalt. Ook de stroom gepromoveerden begint op gang te komen. Voor de komende periode zijn dat Ignaz Worm (PWN), Karin Lekkerkerker (Dunea) en David de Ridder (TU Delft/UGent). Leuk om te noemen is verder dat tijdens de IWA conferentie in Busan de TU Delft in de prijzen viel. Prof Mark van Loosdrecht won de IWA s Global project innovation awards voor het behandelen van zout afvalwater (toiletspoeling met zeewater) met het SANI proces. Prof Jan Peter van der Hoek won IWA s sustainability award in de categorie Excellent Research met het artikel Climate change mitigation by recovery of energy from the water cycle: a new challenge for water management. Tot slot willen wij u attent maken op de komende Vakantiecursus. Het is weer een aansprekend programma met als titel De watercyclus, daar zit wat in. Wij hopen u te kunnen verwelkomen op 11 januari 2013 (lijkt nog heel ver) om onze 65ste verjaardag te vieren. Vooruitlopend op het regeerakkoord kunnen we echter nu al zeggen: we gaan niet met pensioen!! Luuk Rietveld

2 Agenda Data colloquia: Donderdag van uur 25 oktober, zaal november zaal november zaal december zaal 2.62 For information: r.shang@tudelft.nl Promoties Ignaz Worm Topic: Integration of drinking water treatment plant process models and emulated process automation software Datum: 12 november,12.00 uur Lokatie: Aula TU Delft, Senaatszaal Karin Lekkerkerker-Teunissen Topic: Advanced oxidation and managed aquifer recharge:a synergistic hybrid for organic micropollutant removal Datum: 14 november, uur Lokatie: Aula TU Delft, Senaatszaal David de Ridder Topic: Adsorption of organic micropollutants onto activated carbon and zeolites Datum: 15 november, uur Lokatie: Aula TU Delft, Senaatszaal Mini symposium Schade door wateroverlast Datum: 29 november 2012, :00 uur Lokatie: zaal G, Faculteit CiTG Registreren: secr-gez-citg@tudelft.nl Arsenic Workshop Topic: Arsenic in Drinking water Datum: 7 december 2012 Lokatie: UNESCO-IHE, Delft Registreren: Aankondiging Intreerede Walter van der Meer Topic: De drinkwaterzuivering van de toekomst? datum: 15 februari 2013 Afstudeercolloquia Johan Post Topic: Combining Field Observations and Hydrodynamic Models in Urban Drainage Datum: 25 oktober, uur Lokatie: zaal 2.02, Faculteit CiTG Wouter Bosch Topic: The underground connects us Datum: 26 oktober, uur Lokatie: zaal F, Faculteit CiTG Pawel Krzeminski Topic: Activated sludge filterability and full scale membrane bioreactors operation Datum: 22 januari, 9.30uur Lokatie: Aula TU Delft Franca Kramer Topic: Riverbank filtration used as removal step of pharmaceuticals present in river water Datum: 29 oktober, uur Lokatie: zaal E, Faculteit CiTG Workshops International Water Conferences Datum: 4-6 november 2012 Lokatie: West-Indisch Huis Amsterdam Registreren: Bram Stegeman Topic: Calibration in the field of urban drainage as a tool to identify maintenance Datum: 29 november, uur Lokatie: zaal G, Faculteit CiTG 2

3 Onder auspiciën van de Faculteit Civiele Techniek van de Technische Universiteit Delft en met medewerking van Vewin, RIVM, KWR, Waternetwerk, RIONED en STOWA. Plaats: collegezalen A en B, Faculteit Civiele Techniek en Geowetenschappen, Stevinweg 1, 2628 CN Delft PROGRAMMA Ontvangstbalie begane grond Welkomstwoord Prof.dr.ir. Bert Geerkens, Decaan Faculteit CiTG Parallelsessie Drinkwater zaal A Inleiding schoon water Prof.dr.ir. Luuk Rietveld (TU Delft) Strategische innovatie: de creatie van het waterbedrijf van de toekomst Prof.dr. Taco van Someren (Ynnovate) Water met inhoud Lieve Declerq, MSc (Vitens) Parallelsessie Afvalwater zaal B Inleiding vies water Prof.dr.ir. Jules van Lier (TU Delft/Unesco-IHE) Koffiepauze: begane grond en eerste verdieping Leven in het drinkwater distributienetwerk Dr. Hans Vrouwenvelder (TU Delft/Kaust/Wetsus) Flash presentaties NOM in de waterzuivering: Ir. Anke Grefte Detecteren afwijkingen distributienet: Ir. Martijn Bakker Data + models = dynamic information (=sexy): Ir. Ignaz Worm Lunchpauze: begane grond en eerste verdieping Recycling of Industrial Water: The journey of Pearl GT Drs. Koen de Leeuw (Shell P&T EUHT) Flash presentaties Filtration in surface water treatment: Peter Lu, MSc Water supply for developing countries: Dr.ir. Doris van Halem Solar driven desalination in Indonesia: Ir. Reinoud Feenstra Faculteit Civiele Techniek en Geowetenschappen Congres De Watercyclus; daar zit wat in! 65 ste VC: maar nog lang niet met pensioen! 65 ste Vakantiecursus Drinkwater en Afvalwater Vrijdag 11 januari Theepauze: begane grond en eerste verdieping Gezamenlijke slotsessie Uitreiking Waternet Watercyclus Innovatie prijs Uitreiking Jaap van der Graaf prijs De ontdekking en toepassing van onmogelijke bacteriën (Winnaar Spinoza prijs 2012) Prof.dr.ir. Mike Jetten (RU Nijmegen) Het waterschap anno 2012: van lijderschap naar leiderschap Dr. Renze van Houten (Waterschap Aa en Maas) Nereda : Voorbeeld van succesvolle innovatie? Ir. Helle van der Roest (RHDHV) Flash presentaties Anaerobic nutrient rich effluents: Hale Őzgűn, MSc The enzymatic degradation of excess sludge: Steef de Valk, MSc Assessing the quality of sewer pipes: Nikola Stanic, MSc Priester, koopman & ingenieur: iedereen ziet er wat anders in Dr.ir. Fons Nelen (Nelen & Schuurmans/KWN) Flash presentaties Industrial AMBR: Kaan Dereli, MSc High Pressure Digestion: Drs. Ralph Lindeboom Meten in rioolstelsels: Ing. Marco van Bijnen Yes!Delft: from idea to techno-starter Ir. Sid Vollebregt (Elemental Water Makers) De watervoetafdruk: instrument voor overheden en bedrijven Prof.dr.ir. Arjen Hoekstra (Universiteit Twente) NL water innovatie onder het Bestuursakkoord Water: wat biedt de politiek? Joop Atsma, Staatssecretaris van Infrastructuur en Milieu (onder voorbehoud) Nieuwjaarsborrel 3

4 Recent papers in DWES Recent Final Revised Papers 79.Assessing variable speed pump efficiency in water distribution systems, A. Marchi, A. R. Simpson, and N. Ertugrul, 4 juli 2012 Drink. Water Eng. Sci., 5, 15-21, Low-cost multi-stage filtration enhanced by coagulationflocculation in upflow gravel filtration, L. D. Sánchez, L. M. Marin, J. T. Visscher, and L. C. Rietveld, 29 juni 2012, Drink. Water Eng. Sci. Discuss., 5, , Effect of biostimulation on biodegradation of dissolved organic carbon in biological filters, K. Tihomirova, A. Briedis, J. Rubulis, and T. Juhna,10 juli 2012, Drink. Water Eng. Sci., 5, 23-29, The large-scale impact of climate change to Mississippi flood h a z a r d i n N e w O r l e a n s, T. L. A. D r i e s s e n a n d M. v a n L e d d e n 5 juli 2012, Drink. Water Eng. Sci. Discuss., 5, , Robust optimization methodologies for water supply systems d e s i g n, J. M a r q u e s, M. C. C u n h a, J. S o u s a, a n d D. S a v i ć 15 augustus 2012,Drink. Water Eng. Sci., 5, 31-37, Modelling water quality in drinking water distribution networks from real-time direction data, S. Nazarovs, S. Dejus, and T. Juhna,17 augustus 2012, Drink. Water Eng. Sci., 5, 39-45, Accumulation and modeling of particles in drinking water p i p e f i t t i n g s, K. N e i l a n d s, M. B e r n a t s, a n d J. R u b u l i s 3 september 2012, Drink. Water Eng. Sci., 5, 47-57, 2012, Papers in Open Discussion 84. How much are households willing to contribute to the cost recovery of drinking water supply? Results from a household survey, S. Tarfasa, 25 juni 2012, Drink. Water Eng. Sci. Discuss., 5, , Predicting the residual aluminum level in water treatment process, J. Tomperi, M. Pelo, and K. Leiviskä, 27 juni 2012, Drink. Water Eng. Sci. Discuss., 5, , Water use scenarios as a tool for adaptation to climate change of a water supply company, R. Jacinto, M. J. Cruz, and F. D. Santos, 28 juni 2012, Drink. Water Eng. Sci. Discuss., 5, , Preventive strategy in response to climate change and infrastructural failures for Jakarta slum dwellers,v. Pooroe and I. Prabaharyaka 6 aug 2012, Drink. Water Eng. Sci. Discuss., 5, , Non-residential water demand model validated with extensive measurements, E. J. Pieterse-Quirijns, E. J. M. Blokker, E. van der Blom, and J. H. G. Vreeburg, 24 aug 2012, Drink. Water Eng. Sci. Discuss., 5, , Numerical and experimental investigation of leaks in viscoelastic pressurized pipes, S. Meniconi, B. Brunone, M. Ferrante, and C. Massari, 3 sept 2012, Drink. Water Eng. Sci. Discuss., 5, , Fluoride in the drinking water of Pakistan and the possible r i s k o f c r i p p l i n g f l u o r o s i s, M. A. Ta h i r a n d H. R a s h e e d 7 sept 2012, Drink. Water Eng. Sci. Discuss., 5, , Application of DVC-FISH method in tracking Escherichia coli in drinking water distribution networks, L. Mezule, S. Larsson, and T. Juhna, 26 sept 2012, Drink. Water Eng. Sci. Discuss., 5, , 2012 Nieuwsbrief ontvangen? Wilt u onze nieuwsbrief voortaan ook ontvangen? Stuur dan even een naar het secretariaat van de Sectie Sanitary Engineering: secr-gez-citg@tudelft.nl; 4

5 Afstudeerverslagen Riverbank filtration used as removal step of pharmaceuticals present in river water Franca Kramer For several years small concentration of pharmaceuticals and pesticides have been measured in river water. The source of these pollutants in the river water is the increasing consumption of pharmaceuticals by human beings. Most pharmaceuticals are after consumption are not degraded by the human body and thus leave the body with urine. This means that they end up in the wastewater and via the sewer in the wastewater treatment plants. The wastewater treatment plants are only capable of removing a small part of these pharmaceuticals and pesticides from the wastewater; the rest will be discharged into the river with the treated water. Meaning that for instance in the river Rhine a build-up of pharmaceuticals can be measured originating from the pharmaceutical use in Germany. The pharmaceuticals and pesticides measured consist among others of birth control and natural hormones, antibiotics, antimicrobials, pain relievers, and caffeine; compounds with known pharmacological actions in humans and animals. Although quantities of these contaminants in surface water may be low, they constitute a constant exposure, because they are almost constantly present. Effects of these compounds on human health are assumed to be non-existent, but this has not been fully characterized. Toxicological studies have shown that these small pollutants might have an effect on aquatic life. Meaning very small animals in the river have a higher chance of growing mutant forms. A big part of the drinking water produced in the Netherlands is gained from the rivers Rhine and Meuse. 5

6 A large part of the drinking water produced in the Netherlands is gained from the river Rhine and Meuse by drinking water treatment plants. Due to the senescence of the population, more and more pharmaceuticals will be used in the future. This leads to higher pharmaceutical concentrations in the river water. Some are removed with the current treatment, e.g. adsorption with activated carbon, nano filtation and reversed osmosis. But to be able to secure safe and healthy drinking water in the Netherlands future measures need to be considered. Therefore further research on this topic is required. One possible measure to remove pharmaceuticals from river water is using riverbank filtration as a pretreatment step for producing drinking water. This way the water will be gained from the soil next to the river instead of from the river itself. Studies have shown that during riverbank filtration a major part of the pharmaceuticals and pesticides are removed from the river water. However what happens in the riverbank is not fully understood. This is where the topic of my master thesis research starts. Looking at the removal of organic micro pollutants in different layers of the riverbank (oxic, and anoxic zones) and trying to distinguish main removal mechanism of removal; this can be sorption onto the sand or/and biodegradation by microorganisms present in the sand. This study is part of the research project ESTAB, just like the PhD research of Cheryl Bertelkamp. To be able to contribute to this study, I designed and performed a laboratory experiment, using sand and river water from the Lek river (near Oasen). During this study batch processes were used to mimic riverbank filtration for two layers of the aquifer; the oxic- and nitrate reducing zone. In practice bottles were filled with sand and water and samples were taken after certain time steps. These samples were analysed with a LCMS-MS to determine the removal of 20 selected pharmaceuticals and pesticides. Moreover eight other analysing procedures were used to make sure the conditions stay comparable with the natural riverbank. At this moment my lab days are over and my report is almost finished. For me this research is almost finished; hopefully my results can contribute to a small part of the understanding of the processes in the sand of the riverbank. However the knowledge on this field is still very minor, thus there is still a lot to be discovered! francakramer@gmail.com 6

7 Calibration in the field of urban drainage as a tool to identify maintenance Bram Stegeman As a result of in-sewer defects (e.g. root intrusion, attached and settled deposits and sediment) the hydraulic behavior of a sewer system changes. Although the latter could lead to e.g. an increase in urban pluvial flooding, in practice in-sewer defects are often not incorporated in a hydrodynamic model as a result of lack of knowledge and data. From visual inspections it is known that in the combined sewer system of the Professor Fuchslaan catchment (Utrecht, the Netherlands) in-sewer defects are also present. To investigate the influence of the in-sewer defects on the hydraulic behavior of the sewer system, a detailed monitoring network (32 gauging stations) is installed and the sewer system is not cleaned in recent years. In this research the measurement data is also used to check the reliability of the full hydrodynamic model with help from a model calibration procedure. The latter holds that next to the removal of systemic errors, model parameters are optimized with help from algorithms to fit the model results as closely as possible with the measurement data available. Measurement data from the monitoring network revealed that persistent in-sewer defects (e.g. root intrusion) significantly influences the local system behavior and due to in-sewer defect dynamics this varies during and between different storm events. As a result, the in-sewer defect has to be incorporated in the hydrodynamic model during the calibration procedure. In this research various options are investigated to 7

8 mimic the behavior of the in-sewer defect and how to deal with it during model calibration. In addition, a calibration procedure is conducted without the incorporation of the in-sewer defects in the model to investigate the influence on the calibration results. As an alternative to the model calibration process, the theoretical application the Ensemble Kalman Filter is investigated. Development of water level upstream (Lev 13) and downstream (Lev 12) at in-sewer defect (root intrusion). As can be observed the upstream water level increases likely due to a accumulation of debris. Although in preceding period also storm events occurred, the blockage is eventually removed at an intensive storm event. Due to among others complicated in-sewer dynamics and modeling possibilities available, it was not always possible to exactly mimic the influence of the in-sewer defects with the hydrodynamic model. However, a significant model improvement is obtained with help from relatively simple model components, such as an orifice and a weir. The calibration results in which the in-sewer defects are incorporated illustrates that the characteristics of the components are dependent of the in-sewer dynamics in combination with the characteristics of different storm events analyzed. As a result, the model parameters introduced for the in-sewer defect are different for each storm event. The results illustrates that without the incorporation of the in-sewer defects in the calibration process an obvious shift in some model parameter values occurred to compensate for the in-sewer defect influence visible in the measurement data. In addition, as a result of a new balance between the different model parameters, in general the differences between modeled and measured hydraulic behavior increased (i.e. the residues) at the different water level measurement locations. As a result, the presence of the in-sewer defect is visible in both the joint statistical properties of the residues, as well as in the statistical properties of the individual measurement locations. Although in this research not implement, it is likely that the Ensemble Kalman Filter could be used as an alternative to the applied model calibration procedure. The latter has interesting aspects with respect to the parameter optimizing process, since at each time step new measurement data is taken into account and subsequently parameters are estimated. Therefore a significant change in parameter values over time, such as an increase of the hydraulic roughness could be used to identify in-sewer defects. From this research it can be concluded that if once a full hydrodynamic model is calibrated, in-sewer defects could be spotted with help from different calibration runs since next to a deterioration in statistical properties of the residues a change in parameter values is expected. For this purpose, storm events with different characteristics have to be used since these determine next the in-sewer defects dynamics the influence on the local system behavior visible in the measurement data. Next to the model calibration process, the Ensemble Kalman Filter is a promising tool with respect to sewer management. Although more investigation is needed, both methods could be used to save money and effort since sewer inspections does not necessarily need to be performed regularly to determine the state of the sewer system. Since both methods are dependent on measurement data, next to automatic validation of the latter, the amount and exact location of the different measurement locations is an important aspect for further research. bramstegeman@hotmail.com 8

9 The underground connects us Exploratory study into the added value of information exchange between network managers for assetmanagement of underground infrastructures Wouter Bosch an assetmanagement based strategy, requires a number of conditions. Information from the networks themselves and of the surroundings of the networks, are crucial in meeting these conditions. The exchange of information between network managers in the Netherlands, is currently driven by the Wet Informatie-uitwisseling Ondergrondse Netwerken (Act on Information-exchange Underground Networks). However, this is limited to the location data of the networks to prevent damages caused by digging. Another form of information exchange is sharing the short term planning, for decreasing digging costs. By increasing the current exchange of information, possibilities are seen to limit costs and nuisance for the consumers of the services provided by the networks. The reduction of costs and nuisance is the reason why the purpose of the research is to make an exploration of the information network managers gather now, and see where there is potential added value by sharing this information. The added value is expressed in the way it contributes in the balancing of performance, cost, risk and nuisance for consumers. In the Netherlands managers of underground infrastructures are facing the same challenges: aging networks, upcoming replacement waves, change in demand, increasing public awareness and an ever increasing busyness of the underground are a few examples. To tackle these challenges network managers see that management on a reactive basis is not adequate anymore. A (new) form of management called assetmanagement, is seen as a fit strategy to face the mentioned challenges. Assetmanagement seeks a balance between performance, cost and risk in the management of the networks. However, with this new form of management, a different kind of information is necessary compared to management on a reactive basis. Making effective decisions on In the research the following underground infrastructures are considered: drinking water, sewerage, gas, electricity and telecommunications. Because it is expected that the same sort of materials are used in the construction of these networks and the fact that that the networks are situated in the same ground layer, the same need for information is expected for the management of the considered networks. The research is performed by a literature study and interviews with assetmanagers. The literature study gives a theoretical framework of the information requirement and shows to what degree network managers acquire such information. The interviews are to acquire the information need in practice. 9

10 The literature study shows that there are indeed similarities between the materials used and the way these materials fail. Thus showing the same requirement of information. Next to damages done by digging, other causes such as external corrosion, loads due to traffic and tree roots etc. and settlements are of influence on all of the considered infrastructures. Information from the surroundings is important in determining the condition of the infrastructures. Here, there are possibilities to share information. The results from the interview show that combining research of material failure, combining field actions and sharing information about the surroundings of the networks is desirable. In total the results of the research are seven suggestions where information exchange potentially has added value: 1. Combining research of commonly used materials 2. Exchange of failure data 3. Further exchange of location data 4. Information about local influences on the risks 5. Long term planning 6. Combining actions in the field 7. Exchanging experience dealing with the transition from building networks to maintaining networks On the 26th of October I will explain my research further and will elaborate more on the seven suggestions. w.a.bosch@student.tudelft.nl Combining Field Observations and Hydrodynamic Models in Urban Drainage Johan Post Hydrodynamic models are often the main source of information used in engineering practice to judge the performance of urban drainage systems with respect to the occurrence of flooding. If the hydraulic performance is deemed insufficient, these models are used to determine the effect of proposed alterations to the system. does not result in an equally good match for a specific storm event, compared to single event calibration. This research focusses on the application of data assimilation (DA) to address model uncertainties for continuous time series. The process of data assimilation combines measurements and models by updating the set of model parameter values when new measurements are available (see Figure 1). In order to obtain sufficient field observations for data assimilation, a method for the design of a monitoring network capable of collecting information on the relevant processes is elaborated. Due to the fact that hydrodynamic models are subject to uncertainties originating from various sources, the reliability of the model results is limited. These uncertainties can be minimized when a calibrated model is applied. However, is has been found that water level predictions for a storm event other than the storm event used to calibrate the model are less reliable. Furthermore, the use of continuous time series containing multiple storm events for model calibration For two simple examples, the applied data assimilation method is able to accurately simulate water levels and proves to be robust with respect to the initial estimation of the parameter values. Due to time constraints, the implementation of the data assimilation method for the case study of Delft s city centre drainage system has been unsuccessful. For the same case study, a monitoring network has been designed. This network is able to collect a wide variety of information with respect 10

11 to the parameters of interest, while still incorporating some form of redundancy to account for sensor failure and for the cross validation of data. Although it has been found that data assimilation is successful in simulating water levels for continuous time series, more research is needed on the implementation for large scale application in the field of urban drainage. Due to the spread of information over the potential monitoring locations, a well-designed monitoring network is considered to be a prerequisite for the collection of sufficient information for the application of data assimilation. j.a.b.post@student.tudelft.nl Figure 1: principle of data assimilation, adapted from (Solonen, 2011) 11

12 Promotieverslagen Advanced oxidation and managedaquifer recharge:a synergistic hybrid for organic micropollutant removal Karin Lekkerkerker Teunissen Organic micropollutants (OMPs) are present in sources for drinking water and, although in lower numbers and concentrations, also in finished drinking water. Although the risk of impact on human health by individual compounds is judges negligible, there is still discussion about their effect of the mixture of compounds, and water companies should be cautious. The current treatment of Dunea cannot adequately remove OMPs. When extension of the current treatment is considered, the application of an advanced oxidation process (AOP) before managed aquifer recharge (MAR) is proposed as the solution that fits best into the current treatment train. This chemical oxidation step is believed to enhance the natural treatment by MAR, resulting in a synergistic hybrid system against OMPs. This thesis focused on the performance of an oxidative process, implemented in the pre-treatment of Dunea, and its influence on the sequential dune filtration step. AOP and MAR An advanced oxidation process is able to transform many organic micropollutants. UV/H2O2 can remove OMPs by photolysis and by a-selective radical oxidation. O3-AOP can be used as a pre-treatment prior to UV-AOP, where DOC removal, UV-T increase and OMPs conversion by O3/H2O2 result in synergistic effects for this serial AOP application. Managed aquifer recharge has the potential to remove OMPs by biodegradation and adsorption. Batch experiments showed a large diversity in the removal of OMPs by MAR. AOP and MAR result in a synergistic hybrid system, because of the complementary properties of these two processes. MAR can remove by-products and transformation products and dampens peak concentrations. In addition, the natural treatment by MAR is enhanced: because the formation of AOC can results in a higher biodegradation potential and the partial oxidation of parent compounds results is smaller compounds which are more easy biodegraded. The multiple barrier treatment for Dunea For Dunea this thesis showed that low pressure lamps are most favorable for the application of UV/H2O2 in the pre-treatment in Bergambacht. Pre-oxidation by O3/H2O2 resulted in a lower energy consumption 12

13 during subsequent UV/H2O2. The bromate formation was kept below 0.5 µg/l with a peroxide dose of 6 ppm and an ozone dose of 1.5 mg/l. Since Dunea considers to implement AOP in the pre-treatment location before MAR, there is a biological treatment step subsequent to the AOP that can remove by-products (e.g., AOC) and transformation products. Two compounds illustrate the complementary between AOP and MAR at Dunea. The compound carbamazepine showed persistent behavior in the simulated MAR process, but showed good removal during AOP. The compound metformine showed low removal during AOP, but is removed in the MAR process of Dunea. If AOP is installed before MAR, Dunea has a multiple barrier treatment concerning OMPs. The majority of the OMPs are removed before MAR and will not enter the dune system. Further degradation of OMPs can be achieved in the subsequent MAR filtration step. MAR can also remove the transformation products and by-products, resulting in an excellent water quality which is biologically stable. k.lekkerkerker@dunea.nl Adsorption of organic micropollutants onto activated carbon and zeolites David de Ridder specific organic micropollutants are found in their source water, and enables policy makers to include treatment efficacy as a criterium when deciding if new products should be introduced. Numerous organic micropollutants are present in water sources used to produce drinking water, and this suite of organic micropollutants is constantly changing as new products (i.e pesticides, pharmaceuticals, industrial additives) are introduced, while other products are phased out. Organic micropollutants that adsorb poorly on activated carbon can potentially end up in finished drinking water. As such, a modeling approach is required that can give a quick indication of the adsorption efficacy of organic micropollutants. This would allow drinking water treatment plant operatives to make an informed decision on plant operation when In order to identify which mechanisms dominated in the adsorption of organic micropollutants (i.e. solutes) onto activated carbon, the adsorption of a wide range of solutes onto F400 activated carbon was investigated. It was found that hydrophobic partitioning, as represented by the solutes log D value (the ph-corrected octanolwater partitioning coefficient) was an important mechanism which especially dominated the removal of relatively hydrophobic solutes. For more hydrophilic solutes, hydrogen bond formation between the solute and the activated carbon surface strongly affected solute removal. Aromatic solutes showed slighty better 13

14 adsorption than aliphatic solutes, due to the potential to form pi-pi bonds with the basal planes of activated carbon. No significant influence of solute charge or size was observed. This approach was reversed; the adsorption efficacy of two probe solutes, hexanol and 1.3-dichloropropene, on a wide range of commercial activated carbons was investigated. Activated carbon hydrophobicity was measured with various methods; mass increase due to water vapour uptake, oxygen surface density of the activated carbon, contact angle measurements using the capillary rise approach and immersion calorimetry of activated carbon in water. It was found that the water vapour uptake correlated to the oxygen surface density, indicating that the oxygen surface density is a good indicator for the amount of adsorption sites for water. However, the oxygen surface density correlated poorly with the enthalpy of immersion of activated carbon in water, indicating that the oxygen surface density did not give information on the interaction strength between water and activated carbon. Nevertheless, activated carbon hydrophobicity (i.e. activated carbon-water interaction) alone could not explain the observed adsorption. According to thermodynamics, the interaction energy between solute and activated carbon, and solute and water have to be included as well. After deriving these from immersion calorimetry and the literature, respectively, and calculating the (3-phase) interaction of solute and activated carbon in water matrix, a good correlation (r2=0.82) with the observed adsorption is found. Hexanol showed higher solute-carbon interaction than 1,3-dichloropropene, which could be related to the potential of hexanol to form hydrogen bonds with the activated carbon surface, while 1,3-dichloropropene was unable to do so, confirming the previous finding that hydrogen bonding can be an important mechanism in adsorption. The thermodynamic approach was further refined by introducing surface tension components that correspond with van der Waals interaction, and electron donor-acceptor interactions (which also include hydrogen bond formation). Furthermore, it allows to determine solute-activated carbon interactions for solid solutes, which is not possible with the original approach. When activated carbons were preloaded with natural organic matter (NOM) from surface water and wastewater, adsorption was significantly reduced as compared to fresh activated carbon. For negatively charged solutes, this reduction was largest due to 14

15 charge repulsion with the negatively charged NOM preloaded on the activated carbon. High-silica zeolites proved to be interesting alternative adsorbents as, in contrast to activated carbon, NOM molecules cannot enter the zeolite pores and consequently, the negative effects of NOM competition and pore blockage can be avoided. The hydrophobicity and pore size of the zeolites affected their adsorption efficacy; the relatively hydrophobic ZSM5 (Si/Al 80) and Mordenite (Si/Al 200) zeolites showed high adsorption of solutes that closely fit into the zeolite pores. No adsorption was observed on the more hydrophilic Mordenite (Si/Al 30) and DAY (Si/Al 80), which had a relative large pore size. Zeolites are, however, more specific adsorbents then activated carbon and should therefore be regarded as complementary treatment for solutes which are poorly removed by activated carbon, rather than a replacement for activated carbon treatment. The original goal to develop a model to predict the adsorption efficacy of organic micropollutants is within closer reach. The thermodynamic approach can predict solute adsorption reasonably well, although still some experimental input is required to determine the surface tension components of each new activated carbon and each new solute. The predicted adsorption is for demineralized water and fresh activated carbon. As such, the model can give a best case removal efficacy, which can be used in a relative comparison. Pharmaceuticals which showed poor adsorption according to the model are Lincomycine and Cyclophosphamide and care should be taken to prevent these pharmaceuticals to enter source waters for drinking water production. d.j.deridder@tudelft.nl Activated sludge filterability and full scale membrane bioreactors operation Pawel Krzeminski Membrane bioreactors (MBR) become a mature technology and an alternative for the conventional wastewater treatment processes. Among other prospects, MBRs provide high effluent quality, free of suspended solids and very low levels of bacteriological contamination, at a relatively small plant footprint. Despite continuous developments, high operational and maintenance (O&M) costs related to membrane fouling mitigation remains a major challenge and restrain broader technology application. The efficiency of the filtration process in an MBR is governed by the activated sludge filterability, which is determined by the interactions between the biomass, the wastewater and the applied process conditions. The purpose of this thesis was to provide better understanding of the factors impacting activated sludge filterability in relation to full-scale MBR operation. To this end, the research focuses on activated sludge filterability assessment and on fullscale MBR functioning, i.e., design options, operation, performance and energy efficiency, aiming at enhanced and efficient operation of the MBR technology. Research work included both extended on-site measurements and operational data analysis. The Delft Filtration Characterization method (DFCm) was applied to experimentally determine the activated sludge filterability in full- and pilot-scale MBRs treating both municipal and industrial wastewater. To this end activated sludge samples were collected from 14 different MBRs and subjected to filtration test and set of physicochemical analyses. Subsequently, the most important parameters influencing activated sludge 15

16 filterability could have been determined. In addition, the design, operational and performance data were collected from the selected full-scale MBR plants and analysed in respect to plant functioning, i.e., operation, energy efficiency and operational costs. Our results showed that the temperature and wastewater composition are important influencing parameters with respect to filterability. Deterioration of filterability under low temperatures was linked with a slower biodegradation of the wastewater in the mixed liquor compared to high temperatures. The results revealed that sludge parameters usually denoted in literature as membrane fouling indicators, e.g., BPC, SMP and TOC, are not clearly correlated with sludge filterability. Moreover, every parameter alone is a weak indicator of biomass fouling propensity. Combination of activated sludge parameters, i.e., the sludge morphology and relative hydrophobicity, better indicated sludge filterability than the parameters alone. It was proved, under circumstances of low return rates and for MBRs with a separate membrane tank, that, the MLSS concentration should be above a critical MLSS concentration of about 10 g/l to promote filterability improvement in the membrane compartment. Furthermore, an undesired and refractory composition of incoming wastewater, hydraulic and/or organic load shocks, as well as abrupt temperature changes of the influent lead to operational problems and affect sludge filterability. Nevertheless, MBR is a robust and reliable technology as permeate quality mostly complies with the regulations and is independent of the activated sludge quality and encountered operational problems. It was found that, both MBR plant layout and membrane configurations have some influence on overall plant functioning. Different membrane configurations require different mechanical pre-treatments and are associated with different filtration protocols, applied fluxes and membrane cleaning methods. In other words, membrane configurations selection influences mainly plant operational strategies. The MBR plant layout has more distinct influence on overall plant functioning due to indirect impact on operational flexibility and reliability, performance and O&M costs. Moreover, the activated sludge filterability was found independent of membrane configuration but not of the MBR plant layout. The investigated MBRs are under loaded and consequently operated under sub-optimal flow conditions which in turn result in reduced energy efficiency of the plant. Other factors like the system design and layout, the membrane utilization and the strategy applied for the membrane air-scouring are influencing the energy consumption and energy efficiency of an MBR system. Aeration is still major energy consumer, often exceeding 50% share of total energy consumption, therefore the coarse bubble aeration applied for continuous membrane cleaning remains the main target for energy saving actions, especially for installations with flat sheet membranes. Overall, in can be concluded that a good filterability of the activated sludge is indispensible for an efficient and optimal operation of an MBR. Operation with poor sludge filterability will be associated with a cost penalty due to sub-optimal filtration conditions. Wastewater composition and temperature were identified as main parameters influencing activated sludge filterability. MBR plant layout and membrane configuration has an influence on overall MBR functioning and should be chosen carefully. The energy efficiency of an MBR is driven by the hydraulic utilization of the membranes and can be improved mainly by implementation of flow equalization, new aeration strategies and adjusting operational settings to incoming flow. P.Krzeminski@tudelft.nl 16

17 Media 17

18 Nieuwe medewerkers Amer Samy El-Kalliny Hello I am Amer Samy El-Kalliny, born in Egypt in 1978 and brought up in Cairo. I have completed my graduation in Bsc. (1999) did my Masters in chemistry (2005) in Ain Shams University. Since 2000, I got a position of Assistant Researcher in Water Pollution Research Department, National Research Centre in Egypt. I am now a Ph.D. Student in Sanitary Engineering Department, Faculty of Civil Engineering and Geosciences, TU Delft, the Netherlands. I conducted the first phases of my Ph.D. in ChemE, Faculty of Applied Sciences, TU Delft. My Hobbies are playing and watching football, listening to music, and playing PS3, plus travelling a lot. My strength is that I am a quick learner and have a positive attitude and ability to work with the same amount of zeal at any time of the day. My short term goal is to finalize my Ph.D. thesies. My long term goal is to become more responsible and knowledgeable personality and on a respectable position at my work. That s all about me. a.s.m.el-kalliny@tudelft.nl Feifei Wang My name is Feifei Wang and I was born in Weifang, China in I did my master degree at the State Key Lab. of Estuarine and Coastal Research, East China Normal University in Shanghai, China. During my master study, my research was focused on the nutrient limiting factor (nitrogen or phosphorus?) of lake eutrophication. Specifically, I tried to study how nitrogen and phosphorus effected the growth of algae and which one could limit the algal bloom in the lake water. I wrote two papers which were published in Lake Journal and the Journal of Environment Science and Technology and a master thesis on lake nutrient (nitrogen and phosphorus) enrichment bioassay. After finishing my master study, I got a PhD position at Section of Sanitary Engineering of TU Delft and began to research the new field, drinking water treatment, since Sep Now I am focused on the Advanced Oxidation Processes and Artificial Recharge to remove the micro pollutant caused by pesticide, personal care products and so on, under the supervision of Prof. Jan Peter Van der Hoek. Though it is a new field for me, drinking water treatment is to some extent related to my master research topic, the control of lake-eutrophication. Besides, I am enthusiastic and diligent. So, I have a strong confidence to do a good job the coming four years. f.wang-2@tudelft.nl 18

19 Flavio Krzyzanowski My name is Flavio Krzyzanowski Junior. I come from Sao Paulo state, Sao Paulo city, Brazil. I am a Professor of Biology and Microbiology of the Federal Institute of Sao Paulo, Brazil. I made my Master in clinical microbiology at the University of Sao Paulo and now I am making my doctorate thesis in Public Health, also at University of Sao Paulo. My main goal is to evaluate the wastewater sludge application in agriculture soils in Brazil. I am here, at TuDelft, to develop the Quantitative Microbiological Risk Assessmentof this sludge application in order to characterize the sludge that is produced in Sao Paulo State.Professor Gertjan Medema is my Supervisor. f.krzyzanowski@tudelft.nl Borja Sanchez Rodriguez I am Borja Sanchez Rodriguez. I have just start my research period in the Sanitary Engineering department. Previously I have studied chemistry and Msc in Water Pollution. I have started my research at the first of September and will stay till the end of Januari f.b.sanchezrodriguez@tudelft.nl 19

20 Verslagen CONGRESVERSLAG URBAN DRAINAGE MODELLING 9 TE BELGRADO Petra van Daal Belgrado en Servie Van 3 tot en met 7 september 2012 is de negende Urban Drainage Modelling conferentie gehouden in Belgrado, de hoofdstad van Servië. Het congres had we in een Jazz-restaurant aan de Donau: een toilet met 2 potten achter 1 deur (foto 3). Wellicht handig met kleine kinderen, maar over het algemeen zou een muurtje en een extra deur toch handiger zijn. Congres Terug naar het congres zelf. Met een afvaardiging van 11 personen waren de TU Delft (vooral gezondheidstechniek) en de Nederlandse ingenieursbureaus goed zichtbaar. In totaal hebben zij 7 papers en 4 posters gepresenteerd. Daarnaast hebben Francois Clemens en Marie-Claire ten Veldhuis enkele sessies voorgezeten, en Jeroen Langeveld is toegetreden tot het IAHR/IWA Joint Committee Urban Drainage. Ivo Pothof is uitgenodigd om guest-editor te worden voor een speciale uitgave van Urban Water Journal over water-lucht stromingen in Urban Drainage systemen. een vol wetenschappelijk programma, mede doordat de organisatie ook graag de stad en het land wilde promoten. Het eigenlijke congres was in 2,5 heel lange dagen gestopt, met daarvoor 1 dag voor workshops en daarna middag voor een site-seeing tour en een dagtrip naar Romeinse opgravingen. Door de indeling van het congresprogramma en de inspanningen van onze Servische reisgenoot, hebben we een goede indruk van de stad en het land gekregen. Deze is zeker positief. De stad is mooi, heeft een rijke historie die goed zichtbaar is, is niet duur en het weer was uitstekend. Bovendien bestaat er nog echte natuur, waar je niet overal met de auto kunt komen (foto 1). Uiteraard ontbreekt de charme van taxichauffeurs die je (soms) proberen op te lichten niet, moet je als bestuurder goed oppassen voor mogelijke gaten in de weg en vinden kleine autootjes dat ze altijd voorrang hebben. Een van de opvallendste ontdekkingen deden Het programma bestond uit het hele spectrum van (stedelijk) waterbeheer: data, modelleren, toepassingen, management en speciale onderwerpen. De Nederlandse bijdragen waren verspreid over de eerste vier thema s. Tijdens het congres hebben we vooral sessies bezocht over integraal modelleren, modelkalibratie en gevoeligheidsanalyses, neerslag, hydraulica, monitoring en asset management. 20

21 Hoewel het algemene niveau van het congres een beetje tegenviel, waren er wel enkele opzienbarende presentaties. Een interessant voorbeeld is dynamic time warping, waarbij 2 meetsignalen op elkaar worden gefit door te manipuleren met de tijdas. Dit is vooral een interessante techniek wanneer een meetnet enige redundantie heeft, maar door bijvoorbeeld mengingsprocessen signalen met een variabele vertraging doorkomen (Dürrenmatt, Del Giudice, and Rieckermann 2012). Referentie Dürrenmatt, D.J., D. Del Giudice, and J. Rieckermann Dynamic Time Warping Improves Sewer Flow Monitoring. In 9th International Conference on Urban Drainage Modelling, Belgrade. p.m.m.vandaal-rombouts@tudelft.nl Deliver healthy and wholesome drinking water to Citizens -Seminar trip to China with the subtitle of Scientific discussion, culture visit and Chinese food taste, none should be missed Gang Liu Healthy and wholesome drinking water is a basic need for citizens. Provision of healthy and wholesome drinking water through central water supply and distribution systems is a challenging task of the water utilities, with pressures such as increasing urbanization and environmental pollution, climate change, ageing infrastructure and increasing demands of the citizens. The Netherlands has developed significant experience in delivering safe, high standard drinking water, without a disinfectant residual. After gaining remarkable development of economics, the Chinese government is committed to improve the citizens living circumstances and life quality. One of the most important issues is drinking water quality. In the past decades, treatment facilities with new/high techniques have been building up in most of the cities. While topics such as the leakage rate and water quality deterioration during distribution are still main challenge faced by Chinese water companies. The Dutch scientific basis, technology and practices will be of high valuable for the Chinese water industry. NOW funded a seminar on this topic to foster scientific exchange between China and The Netherlands. 21