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  • 1. Abu-Ghunmi, Diana
    et al.
    Abu-Ghunmi, Lina
    Kayal, Bassam
    KTH, School of Industrial Engineering and Management (ITM).
    Bino, Adel
    Circular economy and the opportunity cost of not 'closing the loop' of water industry: the case of Jordan2016In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 131, p. 228-236Article in journal (Refereed)
    Abstract [en]

    The water industry is moving from an end-of-pipe approach consistent with the linear economic model to a circular approach consistent with the circular economy model. The economic dimension of wastewater circularity has not received the attention that other dimensions have; this study attempts to fill this research gap by studying the economic dimension, in order to estimate the net opportunity cost of a non-circular water industry The financial and environmental benefits of treating wastewater, along with the associated operating and capital costs, are calculated to arrive at the opportunity cost and the 'closing the loop charge'. The analytical results reveal an estimated net opportunity cost of 643 million Jordanian dinar (JOD) (907 million US$) if the option not to go circular is chosen, with JOD 212 million (US$ 299 million) of this amount currently squandered. Furthermore, this indicates an average 'closing the loop charge' of JOD0.70/m(3) ($1.0/m(3)), which represents the average shadow price of the associated environmental externalities. Having thus shown a strong economic case for the circular model in the water industry, movements in all economic sectors to adhere to this model appear to be highly desirable.

  • 2. Abu-Khader, M. M.
    et al.
    Shawaqfeh, A. T.
    Naddaf, Z.
    Maity, J. P.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Radon in the groundwater in the Amman-Zarqa Basin and related environments in Jordan2018In: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 7, p. 73-81Article in journal (Refereed)
    Abstract [en]

    The occurrence of radon (222Rn) in environment (groundwater and indoor air) from geogenic sources is receiving an growing attention due to its adverse impact on human health worldwide including Jordan. Highlighting the current status of radon in Jordan, the present study of radon concentrations in ground waters in the Amman-Zarqa basin (AZB) was investigated. Groundwater samples were collected from fifteen wells located in three main areas of Ras Al-Ain, Al-Rsaifeh and Al-Hashemite. Radon concentration was measure using Liquid scintillation counting (LSC) Tri- Carb 3110 with discriminator and the highest values for radon concentration in water were observed in Al-Rsaifeh area and ranged from 4.52 up to 30.70 Bq/l with an average of 11.22 Bq/l, which were attributed to the decay of naturally distributed uranium in phosphate rock from Al-Rsaifeh mines. In Ras Al-Ain area, the radon concentration were noted ranged from 0.6 to 5.55 Bq/l with an average of 2.82 Bq/l, and also in Al-Hashemite area were ranged from 0.77 to 5.37 Bq/l with an average of 4.04 Bq/l. The overall average concentration of tested samples was 5.77 Bq/l and found within the acceptable international levels. Ground water samples of Ras Al-Ain area showed good quality as was tested of low salinity. It recorded the lowest average radon concentration of 2.82 Bq/l. Also, Radon indoor and building materials was reviewed. In conclusion, this study presented an urged need for developing national regulations and standards as well as awareness program concerning the radon status in Jordan.Elsevier B.V.

  • 3. Admass, M.
    et al.
    Dargahi, Bijan
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Hydraulic Engineering.
    3D numerical modelling of flow and sediment transport in rivers2007In: International Journal of Sediment Research, ISSN 1001-6279, Vol. 22, no 2, p. 168-174Article in journal (Refereed)
  • 4.
    Ahlberg, Fanny
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Ivansen, Anders
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Analys över variationer i vattenförbrukning och dess påverkandefaktorer: En fallstudie över områden i Borås2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The steady supply of fresh water is, and has always been, one of the most important functions in human societies. Different users have been able to take advantage of this resource in different extents and for different purposes. The major areas for water usage are drinking water, water supply for industrial purposes and the usage in agricultural sector.

    By dimensioning the supply- and sewer systems accordingly to the demand of the users a more sustainable and optimal system can be achieved. A proper dimensioning has six general factors it should to take in consideration. These are the size of the population, water consumption in residents, general water consumption in schools and offices, water consumption in industry, leakage and different water losses. With a background of these factors this reports main focus and purpose is analysing the variation in water consumption for different consumers (such as residential houses or apartment blocks) in different time intervals (in this report during days and years) and in respect to different factors. The factors that has been chosen to be examined is how water consumption depends on mean age of the consumers and the outdoor temperature. To complete this study water consumption data of different areas in Borås has been provided from the Swedish consultant firm Tyréns. Before analysing the data another study was made by Victor Eliasson, which included the revealing of different faults in the provided data. As a result of this study the most reliable data was chosen to further analysis with respect to the chosen aspects. During the project the calculation- and modelling program Matlab was used alongside the chart program excel. These two programs combined made it possible to handle large amounts of data and present it in different graphs and models. Conclusions could later be made by analyses and different statistical methods. The result from the comparison between areas with different mean ages of the residents showed that the area with high mean age (80 years) hade a higher water consumption than the other areas. The variation in water consumption differed as well between the area with the high mean age compared to the other areas. A regression- and correlation analysis between water consumption and temperature was performed to see if water consumption is depending on the outdoor temperature. The function of a regression analysis is to describe the relation between different parameters with a mathematic model (in this study a linear model). A correlation analysis is then performed to tell how well the mathematic model describes the relation. A conclusion could be made that the water consumption tends to increase with increasing temperature during parts of the year, since a correlation could be found during mars to September. The strongest correlation was in general during May and July for all the areas. No conclusion of how the variation i water consumption depends on different consumers could be made for the analysis during a day and a year. In contrast to the parameters that had a correlation with water consumption there was no visible connection between water consumption over a year or day depending on different users. 

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  • 5.
    Ahlberg, Jesper
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Physics.
    Gustafsson, David
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Physics.
    Distributed snow modelling integrating ground penetrating radar data for improved runoff predictions in a Swedish mountain basin2009In: EGU General Assembly 2009, 2009Conference paper (Other academic)
    Abstract [en]

    Operational forecasts of snow melt runoff in Sweden are currently running with precipitation and temperature as the main input variables and calibrated with runoff data, and there is an interest to make better use of new measurement systems for distributed snow data. At the same time, various data assimilation techniques are becoming more frequently used in hydrological modeling, in order to reduce uncertainties related to both model structure errors and errors in input and calibration data. Thus, it is important to address not only what type of snow data that can be used to improve the model predictions, but also what type of input data and model structures that are optimal in relation to the available snow data. The objective of this study is to investigate to what extent the runoff predictions can be improved by assimilation of temporal and spatially distributed snow data, and if the improvements depend on the choice of model structures, for instance the use of energy balance or day-degree snow models. In order to achieve these objectives a new distributed snow model has been implemented into the hydrological modeling framework HYSS/HYPE. This model can easily be setup with either an energy balance model or a day-degree model for the snow pack calculations, and it is easy to run the model with different spatial resolutions. In the fully distributed case, snow drift processes are implicitly included in the model through a precipitation distribution model, based on topographical information and wind direction. The model was applied to a mountain basin in northern Sweden used for hydropower production, where extensive snow measurements were taken during the last two winters 2007-2009. A climate station is located at the outlet of the regulation lake, including automated point measurements of snow depth, snow mass (snow pillow), snow wetness and snow temperature. Distributed snow cover data was sampled using ground-penetrating radar from snow mobiles. Measurements were taken at the time of the maximum snow cover, providing a data set with snow depth, snow density, snow water equivalent along 20 km long transects in representative areas of the basin. The precipitation distribution model was calibrated using the distributed SWE data from the GPR measurements. Application of the calibrated model to previous years without available snow data show that the runoff predictions was improved compared to calibrations without the distributed snow data, however the improvements were larger for the energy balance compared to the day-degree model. Further developments will include assimilation of the temporal and spatial snow data to adjust the distribution of various input variables, for instance air temperature and wind speed.

  • 6.
    Ahlkvist, Ossian
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Är avloppsreningsverk lämpliga mottagare av backspolvatten från simhallar?2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Swimming pools are used as leisure centers, for sports or as therapeutic rehabilitation, and in Stockholm municipality there are 15 municipal swimming facilities and very many private ones in the form of, for example, hotel pools. A relatively inattentive problem with these pools lies in the chemical reactions that take place in the water. Sodium Hypochlorite reacts in the pool with organic material to form Adsorbable Organic Halides (AOX) and Extractable Organic Halides (EOX). These get stuck in the filter at the plant locally and free chlorine can form additional AOX in the wastewater network. These compounds are harmful for humans and animals to ingest and sometimes even to come into direct contact with. These substances have been studied to bioaccumulate in living organisms and have caused problems such as impaired reproductive capacity and other cell damage. The substances have also been observed to accumulate in dunes in watercourses. These substances that are created then get stuck in the filtration systems that are located locally at the plants due to pressure differences in these. When this happens, the filters need to be backwashed and this generates concentrated contaminated water. 

    In the background, I have examined different kinds of disinfection methods in swimming pools, as well as different ways to treat wastewater of AOX and EOX in treatment plants. This was done to build a good background to the issue at hand of AOX and EOX. 

    In this bachelor's thesis, I have studied how many swimming facilities there are in the catchment area of the Käppalaverket, Bromma treatment plant, and Henriksdal treatment plant. With this information, I have found out how much water is generated by pools at these facilities and supplemented these figures using standard values obtained from managers and estimated from received values. 

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  • 7.
    Ahmed, K. Matin
    et al.
    Univ Dhaka, Dept Geol.
    Bhattacharya, Prosun
    KTH, Superseded Departments (pre-2005), Land and Water Resources Engineering.
    Hasan, Md. Aziz
    Univ Dhaka, Dept Geol.
    Akhter, S. Humayun
    Univ Dhaka, Dept Geol.
    Alam, S. M. Mahbub
    Univ Dhaka, Dept Geol.
    Bhuyian, M. A. Hossain
    Univ Dhaka, Dept Geol.
    Imam, M. Badrul
    Univ Dhaka, Dept Geol.
    Khan, Aftab A.
    Univ Dhaka, Dept Geol.
    Sracek, Ondra
    Masaryk Univ, Fac Sci, Dept Mineral Petrol & Geochem.
    Arsenic enrichment in groundwater of the alluvial aquifers in Bangladesh: an overview2004In: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 19, no 2, p. 181-200Article in journal (Refereed)
    Abstract [en]

    Arsenic in the groundwater of Bangladesh is a serious natural calamity and a public health hazard. Most groundwater from the shallow alluvial aquifers (<150 m), particularly in the Holocene plain lands, are vulnerable to As-enrichment. Delta plains and flood plains of the Ganges-Brahmaputra river system are moderately to severely enriched and more than 60% of the tube wells are affected. Shallow aquifers in the Meghna river basin and coastal plains are extremely enriched with more than 80% of the tube wells affected. Aquifers in the Pleistocene uplands and Tertiary hills are low in As. The vertical lithofacies sequence of the sediments from highly enriched areas of the country show two distinct lithofacies associations-a dominantly sandy channel-fill association and a fine-grained over bank association. The sediments can be grouped into 4 distinct lithofacies, viz. clay, silty clay, silty sand and sand. Thin section petrography of the As-enriched aquifer sands shows that the sands are of quartzolithic type and derived from the collision suture and fold thrust belt of the recycled orogen provenance. Groundwater is characterized by circum-neutral pH with a moderate to strong reducing nature. The waters are generally of Ca-Mg-HCO3 or Ca-Na-HCO3 type, with HCO3- as the principal anion. Low SO42- and NO3-, and high dissolved organic C (DOC) and NH4+ concentrations are typical chemical characteristics of groundwater. The presence of dissolved sulfides in these groundwaters indicates reduction Of SO4. Total As concentration in the analyzed wells vary between 2.5 and 846 mug l(-1) with a dominance of As(III) species (67-99%). Arsenic(III) concentrations were fairly consistent with the DOC and NH4+ contents. The HNO3 extractable concentrations of As (As-NO3) in the sediments (0.5-17.7 mg kg(-1)), indicate a significant positive correlation with Fe-NO3, Mn-NO3, Al-NO3 and P-NO3. The concentrations Of S-NO3 (816-1306 mg kg(-1)) peaked in the clay sediments with high organic matter (up to 4.5 wt.%). Amounts of oxalate extractable As (As..) and Fe (Fe x) ranged between 0.1-8.6 mg kg(-1) and 0.4-5.9 g kg(-1), respectively. Arsenic(ox) was positively correlated with Fe-ox, Mn-ox, and Al-ox in these sediments. Insignificant amounts of opaque minerals (including pyrite/arsenopyrite) and the presence of high As contents in finer sediments suggests that some As is incorporated in the authigenically precipitated sulfides in the reducing sediments. Moreover, the chemical extractions suggest the presence of siderite and vivianite as solid phases, which may control the aqueous chemistry of Fe and PO43-. Reductive dissolution of Fe oxyhydroxide present as coatings on sand grains as well as altered mica (biotite) is envisaged as the main mechanism for the release of As into groundwater in the sandy aquifer sediments.

  • 8.
    Akbaribaseri, Mojtaba
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Phosphorus removal capacity of the materials Polonite and Sorbulite: Influence of saturated falling-head hydraulic conductivity and particle size2024Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Treatment of waste water containing high amount of anthropogenic nutrient is a matter of great necessity acknowledged extensively.  Phosphorus (P) is one of the major nutrients of waste water threatening the aquatic ecosystems. If the phosphorus amount exceeds the system limits, growth of algae and microorganisms in system starts to speed up and consumption of oxygen is hence increased. Because of depletion of oxygen by algae the system is transformed from oxygen based (aerobic) to non-oxygen based (anaerobic) system threatening the ecosystem. 

    The increasing removal actions of phosphorus existing in wastewater by treatment around the world contributes to preserve the natural ecosystem to a better situation. In this study a literature survey was carried out and different methods of phosphorus treatment were investigated such as wetlands filter wells, infiltration beds and filter materials. Then two mineral based filter materials, Polonite® and Sorbulite® were evaluated experimentally in laboratory conditions.  

    In this study hydraulic conductivity and phosphorus sorption capacity of two mineral-based filter materials were analyzed and evaluated. The objective was to investigate the hydraulic conductivity and sorption capacity of the materials. Different particle sizes were also tested aiming to find the optimum particle size of the filter materials.  

    The analysis was done by testing the filter materials in laboratory experiments. Two sets of hydraulic conductivity and sorption batch experiments were done for five different particle sizes, according to universal sieve numbers categories of the particle sizes: (0.25-1 mm) (1-2 mm) (2-4 mm) (4-5.6 mm) (5.6-8 mm). The adsorption mechanism was explained briefly, and the two mineral-based materials are expressed and clarified. Finally, the experiment tests to measure the hydraulic conductivity and sorption capacity were explained. The experimental work was conducted for eight different phosphate concentrations (PO4-P) and various particle sizes of Polonite and Sorbulite. The hydraulic conductivity and sorption capacity in batch experiments were measured for periods of 24 and 48 hours, respectively. 

    The results showed that both filter materials have high and acceptable hydraulic conductivity specifically at large particle sizes. For the adsorption capability it was observed that both materials can adsorb almost all the phosphorus in the solution. Consequently, no major distinction was seen between Polonite and Sorbulite; eventually it is concluded that the current sizes of particles are too much for such range of concentration. The solution for future studies is to carry out the sorption batch experiment for either smaller particle sizes or for higher concentration of phosphate solution.  

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  • 9. Al-Abri, M.
    et al.
    Al-Ghafri, B.
    Bora, T.
    Dobretsov, S.
    Dutta, Joydeep
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Castelletto, S.
    Rosa, L.
    Boretti, A.
    Chlorination disadvantages and alternative routes for biofouling control in reverse osmosis desalination2019In: npj Clean Water, ISSN 2059-7037, Vol. 2, no 1, article id 2Article in journal (Refereed)
    Abstract [en]

    With an ever-increasing human population, access to clean water for human use is a growing concern across the world. Seawater desalination to produce usable water is essential to meet future clean water demand. Desalination processes, such as reverse osmosis and multi-stage flash have been implemented worldwide. Reverse osmosis is the most effective technology, which uses a semipermeable membrane to produce clean water under an applied pressure. However, membrane biofouling is the main issue faced by such plants, which requires continuous cleaning or regular replacement of the membranes. Chlorination is the most commonly used disinfection process to pretreat the water to reduce biofouling. Although chlorination is widely used, it has several disadvantages, such as formation of disinfection by-products and being ineffective against some types of microbes. This review aims to discuss the adverse effect of chlorination on reverse osmosis membranes and to identify other possible alternatives of chlorination to reduce biofouling of the membranes. Reverse osmosis membrane degradation and mitigation of chlorines effects, along with newly emerging disinfection technologies, are discussed, providing insight to both academic institutions and industries for the design of improved reverse osmosis systems. 

  • 10.
    Alderman, Carin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Hydraulic Engineering.
    Andersson, Sophia
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Hydraulic Engineering.
    Cavitation assessment of the Baihetan discharge tunnel – Using Computational Fluid Dynamics2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Recently it has become more common in the construction of large dams to reuse diversion tunnels as flood discharge tunnels in the final structure. These tunnels handle large flows with the characteristics of open channel flow. When such large hydrological forces act upon a structure there are several problems to be expected. One of these is the occurrence of cavitation, which could have potential hazardous erosion as a consequence. Cavitation is the formation and collapse of bubbles that create a shockwave strong enough to erode the underlying material.

    The Baihetan dam is one of the largest hydro power projects in China at present. It has three discharge tunnels that all run the risk of developing cavitation damages. By modelling one of the tunnels using Computational Fluid Dynamics (CFD) it is possible to investigate where in the tunnel structure cavitation is likely to occur.

    This degree project assesses the risk of cavitation erosion in the Baihetan tunnel using the static pressure distribution, the velocity distribution and modern cavitation theory. Several modifications of the tunnel – including alterations in the gradient and construction parameters – are simulated in order to investigate if changes in the design can mitigate the cavitation problem. None of the analysed modifications completely eliminate the problem and aeration is recommended to counteract the problem. This study indicates where cavitation might be a problem in the Baihetan tunnel and can be used as a basis for further research.

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  • 11.
    Alexandroff, Ronja
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Drugge, Paulina
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    A study of the survival rate of Acropora corals outplanted in Damselfish territories: A minor field study in Malolo Lailai, Fiji2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor thesis was executed as a Minor Field Study (MFS) in Malolo Lailai Island, Fiji.The Minor Field Study was funded by the state agency Swedish International DevelopmentCooperation Agency (SIDA). The thesis was written during the spring of 2023 at the RoyalInstitute of Technology (KTH) in Stockholm and the project was created and executedtogether with the organisation Corals for Conservation (C4C) located in Fiji.

    Coral reefs around the world are degraded due to many different anthropogenic stressors,where climate change is a major one. This has affected the reefs in Fiji as sea temperaturesare rising which is causing corals to bleach. Efforts are being made to restore the reefs whichincludes outplanting and monitoring corals in degraded reefs. As conditions in the seaschange, corals are increasingly exposed to predators and disease. Against this backgroundthis project was created in order to see if outplanting corals inside or close to a Damselfish(Stegastes nigricans) territory makes any difference to the survival rate of the corals. Theresults show that corals outplanted outside of a Damselfish territory has a higher risk ofexposure to predators as well as foragers which leads to a lower survival rate. The conclusionthat was made was that planting corals inside of a Damselfish territory therefore increases thechances of corals surviving.  

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  • 12.
    Almulla, Youssef
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Ramirez Gomez, Camilo
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Joyce, Brian
    Stockholm Environm Inst, SEI US, Boston, MA USA..
    Huber-Lee, Annette
    Stockholm Environm Inst, SEI US, Boston, MA USA..
    Nerini, Francesco Fuso
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    From participatory process to robust decision-making: An Agriculture-water-energy nexus analysis for the Souss-Massa basin in Morocco2022In: Energy for Sustainable Development, ISSN 0973-0826, E-ISSN 2352-4669, Vol. 70, p. 314-338Article in journal (Refereed)
    Abstract [en]

    The Water-Energy-Food (WEF) framework is widely used to address sustainability and resource management questions. However, many WEF methods miss engaging with stakeholders in the process. In this study, we intro-duce a stakeholder-driven and model-supported robust nexus decision-making framework. This methodology is exemplified by a case study in the Souss-Massa basin (SMB) which has significant importance for the agricultural sector in Morocco. However, the water scarcity exacerbated by climate change, overexploitation of groundwater and heavy use of fossil fuels for pumping is threatening the future of this fertile land. An integrated agriculture, water and energy model was developed to explore various potential solutions or scenarios such as desalination, wastewater reuse and improved water productivity. The analysis revealed that engaging with stakeholders and developing common robust nexus decision metrics is essential to establishing a shared and transparent approach to address the complicated nexus challenges. It also showed that no one solution can address all nexus challenges and highlighted the need for an integrated strategy that stimulates the contributions from different sectors. Fi-nally, the transition from fossil fuel groundwater pumping to solar pumping is shown to be economically and en-vironmentally viable.

  • 13.
    Amiri, Vahab
    et al.
    Department of Geology, Faculty of Science, Yazd University, Yazd, Iran.
    Li, Peiyue
    School of Water and Environment, Chang’an University, No. 126 Yanta Road, Xi’an, 710054, China Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of the Ministry of Education, Chang’an University, No. 126 Yanta Road, Xi’an, 710054, China.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. KWR Water Cycle Research Institute, Groningenhaven 7, 3433 PE, Nieuwegein, The Netherlands.
    Nakhaei, Mohammad
    Department of Applied Geology, Faculty of Earth Science, Kharazmi University, Tehran, Iran.
    Mercury pollution in the coastal Urmia aquifer in northwestern Iran: potential sources, mobility, and toxicity2021In: Environmental Science and Pollution Research, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 28, no 14, p. 17546-17562Article in journal (Refereed)
    Abstract [en]

    The concentration of total dissolved mercury (HgT) in surface and groundwater resources in the coastal parts of Urmia aquifer (NW of Iran) was investigated to identify the possible sources and sinks of mercury and the geochemical mechanisms controlling its mobilization. The distribution of water samples on the Piper diagram demonstrates that most samples have the Ca-Mg-HCO3 facies. From 62 water samples collected in this area, one sample contained HgT concentrations exceeding the maximum contaminant level recommended by the WHO (6 μg/L). The principal component analysis (PCA) produced five principal components. The positive moderate correlation of HgT with EC, Cl, K, Mg, and Na indicated that the weathering of geological formations was one of the main sources of mercury in groundwater samples. Position of water samples in Eh-pH regions where microorganisms involved in mercury methylation and mineralization were potentially active demonstrated that the aquifer had undergone sulfate reduction and had reached the final stage of the terminal electron accepting process (TEAP) sequence in the methane production processes which are limited to only 37% of the water samples that have anaerobic conditions. Some Hg-bearing species are in nonequilibrium geochemical conditions. The supersaturation of water samples with magnetite and goethite indicated that these Fe-bearing minerals could act as the strong reducing agents for the reduction of Hg(II) to Hg(0).

  • 14.
    Andersson, Josefin
    KTH, School of Architecture and the Built Environment (ABE).
    Hållbar Dagvattenhantering på Kvartersmark: En utvärdering av hur väl den planerade dagvattenhanteringen fungerar i verkligheten2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Storm water management in residential areas is facing tough challenges. Climate change, with its altered precipitation patterns, in combination with an increasing development rate, results in higher risk of flooding with its complications. EU-Water Framework Directive (WFD) and its environmental quality standards, set to achieve good chemical and biological status in all waters, got a more strict interpretation after the implementation of the ruling of Weserdomen. This means that no activity is allowed that cannot prove not to endanger prevailing environmental quality standards. This complicates the planning process and infrastructure development since some form of WFD assessment needs to be performed.

     

    This master´s thesis is of importance since it identifies common occurring problems within the planning- and construction process and highlights ways to achieve a more sustainable storm water management, where environmental quality standards are not jeopardized, in the future. An evaluation is performed in terms of interviews, a literature review and by using a storm water model called StormTac applied on two case studies. Results of this thesis show that lack of communication, vague directives, inadequate design and maintenance of storm water facilities are reasons that a sustainable storm water management is not achieved.

     

    Results from modeling the storm water situation prior to construction of the residential areas were set as benchmarks, which were not to be exceeded by results from modeling areas after construction. The purpose of this was to not endanger the current storm water state and thereby not risk violating prevailing environmental quality standards. The result from modeling the storm water situation after construction shows that both case studies exceed the flow and pollution load benchmarks. Because of this, solutions to the current storm water situation was created and modeled to achieve the study aim.

     

    StormTac can be applied as a tool for comparison of flow and pollution load prior to and after construction, given that the same land uses are used in both cases. Land use choices should be evaluated and the degree of uncertainty should be considered when interpreting the results.

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  • 15.
    Annaduzzaman, Md
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Chitosan biopolymer as an adsorbent for drinking water treatment: Investigation on Arsenic and Uranium2015Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    In many countries over the world (including Sweden), metal toxicity in freshwater resources causes a severe drinking water quality problem and poses a threat to the environment and human health. Among the different toxic metals in the water resources of Sweden, arsenic and uranium are the biggest threats to health. These elements, over long time consumption, may even lead to cancer and/or neurological disorder. Most of the wells are installed in crystalline and sedimentary bedrock and the received water comes from water bearing fractures in the bedrock. The handling of such water is an issue and there is a need to reduce the arsenic and uranium exposure by improving processes and technologies. It is a very serious problem demanding a safe, sustainable and eco-friendly arsenic and uranium removal technology prior to drinking water supply. Different treatment systems are available, but many of them are not suitable due to their high cost, operation complexity and waste management issues. Through this study, chitosan biopolymer the second largest abundant polysaccharide on earth after cellulose, was verified as a potential adsorbent for arsenic(V) and uranium(VI) removal from water solution. Adsorbent characterizations were also conducted by XRD, FTIR, SEM, UV-visible spectrum and TGA/DTA investigations. Bench-scale batch experiments were conducted using chitosan biopolymer (DDA-85%) as an adsorbent to determine the arsenic(V) and uranium(VI) removal efficiency, by allowing four important effective parameters e.g. chitosan dosages, pH, contact time and contaminant concentration. The adsorption data at optimum conditions were fitted with Langmuir, Freundlich and Dubinin-Radushkhevic (D-R) isotherm and Lagergren pseudo-first-order and pseudo-second-order kinetic model to investigate the adsorption process. The characterization of materials assured the presence of effective amino, hydroxyl, and carboxyl groups of chitosan. Another advanntage is that the materials are bio-degradable. The results show that the arsenic(V) and uranium(VI) removal efficiency was 100% and 97.45% after 300 minutes with optimum pH of 6.0 and 7.0 respectively. The optimum adsorbent dosages and initial concentration were 60 and 80g/L and 100 and 250 µg/L respectively. The adsorption process was suitably described by Freundlich isotherm (R2 = 0.9933) and Langmuir isotherm (R2 = 0.9858) correspondingly for arsenic(V) uranium(VI) compared to other isotherms. This is an important indicator of homogeneous monolayer adsorption of metals. For both of arsenic(V) and uranium(VI), pseudo-second-order explained the adsorption kinetics better than pseudo-first-order and the second-order kinetic regression coefficient (R2) were 0.9959 and 0.9672 correspondingly. Connecting to the above mentioned results, it can be summed up that the chitosan biopolymer (DDA 85%) can be used as an inexpensive, sustainable and environment-friendly treatment option for arsenic(V) and uranium(VI) contaminated drinking water.

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    Annaduzzaman, M. (2015)
  • 16.
    Ardakani, Amir Hossien Hatefi
    et al.
    Univ Semnan, Coll Nat Resources & Desert, Dept Management Arid & Desert Reg, Semnan, Iran..
    Shojaei, Saeed
    Univ Tehran, Fac Nat Resources, Dept Arid & Mt Reg Reclamat, Tehran, Iran..
    Shahvaran, Ali Reza
    Iran Univ Sci & Technol, Sch Civil Engn, Tehran, Iran..
    Kalantari, Zahra
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. Stockholm Univ, Dept Phys Geog, S-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, S-10691 Stockholm, Sweden..
    Cerda, Artemi
    Univ Valencia, Dept Geog, Soil Eros & Degradat Res Grp, Blasco Ibanez 28, Valencia 46010, Spain..
    Tiefenbacher, John
    Texas State Univ, Dept Geog, San Marcos, TX USA..
    Selecting potential locations for groundwater recharge by means of remote sensing and GIS and weighting based on Boolean logic and analytic hierarchy process2022In: Environmental Earth Sciences, ISSN 1866-6280, E-ISSN 1866-6299, Vol. 81, no 1, article id 8Article in journal (Refereed)
    Abstract [en]

    Growing demand for water, as a consequence of population growth, farmland irrigation, and industrial expansion, results in groundwater resources exploitation. This, in combination with droughts induced by climate change, has caused a sharp drop in groundwater levels throughout arid and semiarid countries. In Iran, all these factors are resulting in alarming water scarcity. Appropriate management and control of existing water resources can overcome water shortages, with healthy and sustainable management of groundwater as one of the most efficient tools. Artificial recharge of aquifers can be used to replenish water supplies and restore the water resources in Iran and other semiarid and arid countries, but selection of the right location for runoff collection is essential to achieve success. Precipitation, slope, geology, lineament density, drainage density, aquifer water quality, groundwater level, vegetation, and land use were selected in this study as key factors in locating suitable sites for artificial recharge. The weight of each, in terms of importance and impact on aquifer recharge, was determined using remote sensing techniques to prepare layers and analytic hierarchy process (AHP) and Boolean logic to identify the optimal weight for each factor. Geographic information system (GIS) was used for modeling, applying the weight of each criterion, and producing a final map. The results showed better performance of AHP than Boolean logic. For artificial recharge, 9.9% of the total study area (Mahdishahr in northern Iran) was found to be in a very good position and 22.6% in a good position. On filtering the privacy layer of fountains and aqueducts, the very good and good area declined to 8.4% and 14.7% of the total area, respectively, and mainly comprised alluvial valleys and coarse alluvial sediments with low slope and drainage density.

  • 17.
    Arregul, Ane
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Innovative solutions for odours reduction from wastewater treatment.2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 18.
    Aspegren, Martina
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Rutegård, Regina
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Möjligheten att använda Viträsket som vattentäkt: En studie om Runmarös vattensituation2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    According to the UN and Sweden’s environmental objectives it is important to attain a high water quality and a sustainable use of freshwater. More and more people are currently moving out to the archipelago, which increases the use of freshwater on the islands, especially during summer when guests tend to visit as well. Runmarö is an island in Värmdö archipelago where the residents currently only have individual wells and sewage systems. Runmarö is more vulnerable to disruption of the freshwater, compared to the mainland, and if a groundwater shortage were to happen during the summer, it would be a big concern. 

    Using the surface water from one of the island’s lakes could be an alternative to the use of water. The largest lake on the island is named Viträsket and is located on the southern part of Runmarö. Since cold temperatures might affect the water pipes negatively, it is more appropriate to use the seawater from the lake during the summer. In this report it is examined whether seawater can be used as a water supply on Runmarö and if Viträsket is an appropriate water source. For the seawater to be used on the island, the residents will have to form a community facility. 

    Literature studies were conducted to understand the prerequisites on the island and what further investigations could be carried out in this report. A field study was also carried out on the island where residents were interviewed about Runmarö’s current water situation and their thoughts about seawater and community facilities. The tap water was also tested at the interviewee’s homes. A test from Viträsket was collected as well to get a grip of its water quality. Bo Olofsson and Erni Bergenstråhle contributed with existing data of different wells on Runmarö. During the field study, Bergenstråhle was also interviewed about whether it is reasonable to use community facilities and seawater on Runmarö. 

    If the water samples collected from Viträsket and the water taps has a higher percentage than Livsmedelsverket recommends for a certain substance, it could be possible to drink the water, but one should be observant. Only two of the tap water tests had a percentage lower than Livsmedelsverket’s limits. The other tests had at least one substance that exceeded the limit. Lake Viträsket had a high percentage of culturable microbes that exceeded Livsmedelsverket’s limit. These microbes are not suitable to consume over a longer period of time. 

    The interviewed residents were all open to join a community facility, they do however prefer it if someone else brings up the question and organizes the start of the process. Runmarö’s interest group handles the infrastructure issue on the island among other things. They might therefore be able to organize the process of creating and building a community facility. The seawater from Viträsket can be used for things such as the laundry machine, dishwasher, shower, toilet and irrigation without further cleaning. To be used as drinking water, it needs to be cleaned and cooled down, otherwise it might affect a person’s health negatively. From a technical point of view, it is more reasonable for the residents living close to Viträsket to use the seawater from Viträsket. Also, it is important to investigate how the water pipes would affect the wildlife around Viträsket. Furthermore, calculations on how much water Viträsket can supply and how many households that can use Viträsket as a source of water needs to be conducted. 

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  • 19.
    Axelsson, Johan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Hydraulic Engineering.
    Knutsson, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Hydraulic Engineering.
    Numerical modeling of a slotted flip bucket spillway system – The Shibuya Hydropower Project. 2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    CFD is today a big part of the design process in hydraulic engineering and is more economical and time efficient than traditional scale models. But, there are still issues concerning the agreement with scale models in large and complex geometries.

    In this degree project a high head, five channeled, slotted flip bucket spillway system is analyzed with the CFD software FLUENT and compared with existing scale model results.

    The sought hydraulic parameters in each channel were the discharge capacity, the pressure distribution and the throw distance from the flip buckets.

    The discharge capacity and pressure distribution was practically equal for all five channels and only the throw distance from Channel 1 deviated from the others. The agreement with data from the scale model is quite low.

    The biggest error sources behind the bad agreement may depend on the lack of computational power which led to bad choice of cell size, model delimitations and simplifications.

    CFD models can easily be built up by people without experience in hydraulics which can lead to fatal errors when building up the model and interpreting results. Hence, long experience in CFD or verification of the numerical results with several different hydraulic parameters is the only way to guarantee qualitative results from CFD modeling.

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  • 20. Bakowska, A
    et al.
    Plaza, Elzbieta
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Water, Sewage and Waste technology.
    Medrzycka, K
    Influence of sulphanilamide in wastewater on Anammox process performance2006In: Water and Environmental Management Series / [ed] Stuetz, R., Teik-Thye, L., London: IWA Publishing, 2006, p. 69-76Chapter in book (Other academic)
  • 21.
    Bakyayita, Grace Kizito
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. Makerere University, Kyambogo University.
    Batch Sorption Studies of Aqueous Cadmium and Lead from Contaminated Water onto Selected Biosorbents2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Groundwater, wastewater, surface runoff and surface water samples from Lake Victoria basin, Uganda was assessed for trace metals contamination. Untreated, base-treated and peroxide-treated biosorbents from Albizia coriaria, Coffea canephora, Cyperus papyrus, Erythrina abyssinica and Musa spp were investigated for removal of selected trace metals from contaminated water in batch studies. The assessed shallow groundwater and surface water was contaminated with iron and manganese. Selected speciation studies using Visual MINTEQ showed that in leachates from Municipal dumpsites 74% of the metal ions were bound to DOM, 13% were free ions and 13% were in inorganic forms moreover for urban streams 37% of the metal ions were bound to DOM, 44% were free ions and 19% were in inorganic forms. The metal levels in surface water, landfill leachate and surface runoff showed elevated levels and revealed increased risks to environmental health. Risk analysis based on the Swedish EPA showed that varied risks of negative effects in 30% – 76% of the sample sites ranging from high to increased risk in surface water whereas the results from Bio-met tool showed potential risk to toxicity effects of Cu2+, Ni2+, Zn2+ and Pb2+ in 15.3% - 30.8% surface water samples and 8.3% - 62.5% groundwater samples. Batch sorption studies revealed that the optimal conditions for Cd2+ and Pb2+ ions uptake were; pH 3.5 – 5.0 for contact time 3.0 – 3.5 hours and biosorbent dosage 10 – 12.5 g/L. Base-treated biosorbents showed 10 – 17 % sorption enhancement for Cd2+ ions and 1.6 – 2.3 % uptake reduction for Pb2+ ions. The biomass negative potential for binding base cations was in the order; Musa spp. > A. coriaria > E. abyssinica and base treatment reduced DOC leaching from biosorbents in the order; E. abyssinica > A. coriaria > Musa spp. Speciation studies showed that more ions were complexed to DOC in solutions at various pH levels. The maximum sorption intensities for both Cd2+ and Pb2+ ions uptake onto biomass occurred for low initial metal concentration; 5 mg/L. Freundlich model best fitted data for Pb2+ ions ions uptake whereas Temkin model fitted the sorption data for Cd2+ ions onto both treated and untreated biomass. For peroxide treated biomass, the maximum sorption efficiencies for both Cd2+ and Pb2+ ions were between 95.2 – 98.7% for C.canephora, 79.9 – 92.2% for Musa spp. and 42.0 – 91.3% for C.papyrus in non-competitive media and 90.8 – 98.0% for C.canephora, 56.4 – 89.3% for Musa spp. and 19.5 – 90.4% for C.papyrus in competitive media. The Langmiur model fitted non-competitive sorption data with 0.769 ≤ R2 ≥ 0.999 and the Freundlich model fitted competitive sorption data with 0.867 ≤ R2 ≥ 0.989. The pseudo second order kinetic model fitted the sorption data for Cd2+ and Pb2+ ions for untreated, peroxide treated and base treated biomass with 0.917 ≤ R2 ≥ 1.000. The sorption of trace metals was a complex potentially monolayer chemisorption with heterogeneous surface properties exhibited. In competitive sorption, sorption suppression effects observed were greater for Cd2+ than Pb2+ ions. The comparative studies on sorption performance presented agreement and no significant difference between the untreated and base treated biosorbents. 

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  • 22.
    Bakyayita Kizito, Grace
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Equilibrium and Kinetic Batch Studies of Cadmium and Lead sorption using Low Cost Biosorbents2014Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Agricultural wastes; Albizia coriaria, Coffea canephora, Cyperus papyrus, Erythrina abyssinica and Musa spp were evaluated for uptake of aqueous Cd2+ and Pb2+ ions in single- and binary-component solutions. Untreated, base-treated and peroxide-treated biomasses were employed in batch studies. The optimal conditions for Cd2+ and Pb2+ ions biosorption were  pH 3.5 – 5 for contact time 3.0 – 3.5 hours and biosorbent dosage 10 – 12.5 g/L. Base-treated biosorbents showed a 10 – 17 %  sorption enhancement for Cd2+ ions and a 1.6 – 2.3 % uptake reduction for Pb2+ ions. The sorption capacities for Cd2+ and Pb2+ ions for base-treated biosorbents were between 1.738 and 1.760 mg g-1 compared to 1.415 – 1.539 mg g-1 for untreated materials. The maximum biosorption of peroxide treated materials in single component media was between 0.819 and 1.595 mg/g for Pb2+ ions and between 0.044 and 1.343 mg/g for Cd2+ ions while in binary component media it was between 0.472 and 1.303 mg/g for Pb2+ ions and between 0.008 and 0.195 mg/g for Cd2+ ions. The pseudo-second order kinetic model suitably fitted the Cd2+ and Pb2+ ions biosorption data with regression coefficients (R2); 0.892 – 1.000 for peroxide-treated materials and 0.9784 – 0.9999 for base-treated biosorbents which implied that the biosorption was mainly a chemisorption process. The base treated biosorbents had better sorption performance for Cd2+ ions than peroxide treated materials and untreated biomass whereas the order for Pb2+ ions biosorption was untreated > base treated > peroxide treated materials. All materials showed superior selectivity for Pb2+ ions biosorption in comparison to that of Cd2+ ions in single- and binary-component media. A. coriaria performed best of the base treated biosorbents while C. canephora performed best amongst peroxide treated materials for Cd2+ and Pb2+ ions biosorption in single-and binary-component media. In the competitive biosorption, Cd2+ ions showed higher synergistic effects than Pb2+ ions although Pb2+ ions were preferentially sequestered even when the Cd2+:Pb2+ ions ratio was increased through 3:2, 2:1, 3:1 and 5:1. Of the three isotherm models evaluated against the experimental data, the Langmuir model generally fitted the sorption data for both metals. Regression coefficients for the Langmuir model were; 0.983 ≤ R2 ≥ 1.000 for single-component and 0.939 ≤ R2 ≥ 1.000 for binary-component solutions which revealed that the biosorption was potentially monolayer. The biosorption equilibrium coefficient                          values and change in Gibbs’ free energy  values showed that Pb2+ ions biosorption was more thermodynamically favoured than that of Cd2+ ions in single-component and binary-component media. The materials studied displayed potential for use as biosorbents for remediation of aqueous Cd2+ and Pb2+ ions.

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    Thesis
  • 23.
    Bakyayita Kizito, Grace
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Kulabako, Robinah
    2Department of Civil and Environmental Engineering, Makerere University, Uganda.
    Nalubega, Mai
    Water and Sanitation Department, African Development Bank, Tunis, Tunisia.
    Norrström, Ann-Catrine
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Equilibrium batch studies for biosorption of Cd(II) and Pb(II) ions from single-and binary-component aqueous mediaManuscript (preprint) (Other academic)
  • 24.
    Bakyayita Kizito, Grace
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Norrström, Ann-Catrine
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Nalubega, Mai
    Water and Sanitation Department, African Development Bank, Tunis.
    Robinah, Kulabako
    Department of Civil and Environmental Engineering, Makerere University, Uganda .
    Kinetic studies of Cd (II) and Pb (II) ions biosorption from aqueous media using untreated and chemically treated biosorbents2014In: Water Science and Technology: Water Supply, ISSN 1606-9749, E-ISSN 1607-0798, Vol. 69, no 11, p. 2230-2236Article in journal (Refereed)
    Abstract [en]

    Untreated and chemically treated Albizia coriaria, Erythrina abyssinica and Musa spp were studied in batch for uptake of Cd2+ and Pb2+ ions at pH 2.0–9.0 and agitation time; 30–390 min. Optimum biosorption conditions were; pH 4 for Pb2+ ions and pH 5 for Cd2+ ions, contact time was 3.5 hours at 24 ± 1 °C for 10 mg/L biosorbent dosage and initial metal ions concentration of 20 mg/L. Chemical treatment had a 10–17% biosorption efficiency enhancement for Cd2+ ions and a 1.6–2.3% reduction effect for Pb2+ ions. The sorption capacities for Cd2+ and Pb2+ ions for treated biosorbents were between 1.760–1.738 mg g−1 compared to 1.415–1.539 mg g−1 for untreated materials. The pseudo second order model suitably fitted the Cd2+ and Pb2+ ions biosorption data with regression coefficients (R2) between 0.9784–0.9999. Fitting of the Ho model to the experimental data showed that the biosorption mechanism for both metal ions studied was mainly a chemisorption process. Therefore, treated A. coriaria, E. abyssinica and Musa spp were potential biosorbents for remediation of Cd2+ ions and the untreated materials suitable for removing Pb2+ ions from contaminated aqueous media.

  • 25.
    Baresel, Christian
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Environmental management of water systems under uncertainty2007Doctoral thesis, comprehensive summary (Other scientific)
    Abstract [en]

    Hydrological drainage/river basins constitute highly heterogeneous systems of coupled natural and anthropogenic water and pollutant flows across political, national and international boundaries. These flows need to be appropriately understood, quantified and communicated to stakeholders, in order to appropriately guide environmental water system management. In this thesis, various uncertainties about water and pollutant flows in drainage/river basins and their implications for effective and efficient water pollution abatement are investigated, in particular for mine-related heavy metal loadings in the Swedish Dalälven River basin and for nitrogen loadings in the Swedish Norrström drainage basin. Economic cost-minimization modeling is used to investigate the implications of pollutant load uncertainties for the cost-efficiency of catchment-scale abatement of water pollution.

    Results indicate that effective and efficient pollution abatement requires explicit consideration of uncertainties about pollution sources, diffuse contributions of the subsurface water system to downstream pollutant observations in surface waters, and downstream effects of different possible measures to reduce water pollution. In many cases, downstream load abatement measures must be used, in addition to source abatement, in order to reduce not only expected, but also uncertainties around expected pollutant loads. Effective and efficient environmental management of water systems must generally also consider the entire catchments of these systems, rather than focusing only on discrete pollutant sources. The thesis presents some relatively simple, catchment-scale pollutant flow analysis tools that may be used to decrease uncertainties about unmonitored water and pollutant flows and subsurface pollutant accumulation-depletion and diffuse loading to downstream waters.

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  • 26.
    Baresel, Christian
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Destouni, Georgia
    Diffuse subsurface zinc loads from mining areas in the Dalälven River Basin, Sweden2009In: Hydrology Research, ISSN 1998-9563, Vol. 40, no 5, p. 445-453Article in journal (Refereed)
    Abstract [en]

    The zinc load from the Dalalven River to the Baltic Sea is greater than for any other watercourse in Sweden. This paper investigates zinc mass flows into and through the Dalalven River from major mining areas within its drainage basin. Reported zinc mass flow data for this river are re-analyzed using an input-output flow analysis approach. Results show major inconsistencies in previous data interpretations which totally neglected possible zinc mass load contributions from the groundwater system to the river. This paper quantifies significant subsurface zinc load contributions that are consistent with all independently available data. Furthermore, a possible explanation for why these subsurface contributions may have been missed in previous studies and by the prevailing Swedish environmental monitoring system is provided. The study indicates that the input-output flow analysis approach may be generally useful for identifying and quantifying diffuse, unmonitored and uncertain pollutant load contributions from ground- to surface water systems.

  • 27.
    Baresel, Christian
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Destouni, Georgia
    Estimating subsurface nitrogen accumulation–depletion in catchments by input–output flow analysis2006In: Physics and Chemistry of the Earth, ISSN 1474-7065, E-ISSN 1873-5193, Vol. 31, no 17, p. 1030-1037Article in journal (Refereed)
    Abstract [en]

    We use input-output analysis of nitrogen flows between various sources-sectors and natural waters in the Swedish Norrstrom drainage basin for investigating and bounding the implication range of some uncertainty sources for results of subsurface nitrogen accumulation-depletion in this basin. We quantify different possible base and extreme assumptions of nitrogen discharges and transport pathways from agriculture to surface and groundwater in the basin. The results are robust in showing considerable nitrogen accumulation-depletion flow interactions taking place between the basin's mobile water and accumulated nitrogen pools in soils, sediments and/or relatively immobile subsurface water zones for all different scenario assumptions. Similar scenario robustness is also found in resulting relative contributions of different active nitrogen source-sectors to nitrogen flows in natural water systems. In the Norrstrom basin, and possibly more generally, nitrogen accumulation-depletion flows to and from accumulated legacies for the future or from the past appear therefore to be more important for water quality than current nitrogen discharges from active source-sectors.

  • 28.
    Baresel, Christian
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Destouni, Georgia
    Novel Quantification of Coupled Natural and Cross-Sectoral Water and Nutrient/Pollutant Flows for Environmental Management.2005In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 39, no 16, p. 6182-6190Article in journal (Refereed)
    Abstract [en]

    Human water use and anthropogenic water pollution and ecosystem deterioration have increased so much that it is now a strategic challenge to maximize benefits from various possible water uses, while ensuring that basic human needs are met and the environment is protected. We propose and develop a novel use of input-output flow analysis as a relatively simple, compact and powerful tool for quantification of coupled natural and cross-sectoral flows of water, nutrients, and pollutants in catchments. The tool quantifies implications of various environmental regulation and management scenarios for both natural water systems and engineered-economic systems and sectors that use and impact natural waters for meeting human needs. Specific case study application to water and nitrogen flows in the Swedish Norrstrom drainage basin indicates considerable nitrogen load contributions to surface and coastal waters from slow groundwater flow paths and legacies of accumulated nitrogen in subsurface and immobile water pools. This implies that effective nitrogen load abatement cannot focus only on active sources but must also include downstream measures, which can capture and abate nitrogen/pollutant loading from different types of known and yet unknown point and diffuse sources within associated catchments.

  • 29.
    Baresel, Christian
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Destouni, Georgia
    Subsurface Water System Contributions to Surface Water Zinc Loads in Mining AreasManuscript (Other academic)
  • 30.
    Baresel, Christian
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Destouni, Georgia
    Uncertainty-Accounting Environmental Policy and Management of Water Systems2007In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 41, no 10, p. 3635-3659Article in journal (Refereed)
    Abstract [en]

    Environmental policies for water quality and ecosystem management do not commonly require explicit stochastic accounts of uncertainty and risk associated with the quantification and prediction of waterborne pollutant loads and abatement effects. In this study, we formulate and investigate a possible environmental policy that does require an explicit stochastic uncertainty account. We compare both the environmental and economic resource allocation performance of such an uncertainty-accounting environmental policy with that of deterministic, risk-prone and risk-averse environmental policies under a range of different hypothetical, yet still possible, scenarios. The comparison indicates that a stochastic uncertainty-accounting policy may perform better than deterministic policies over a range of different scenarios. Even in the absence of reliable site-specific data, reported literature values appear to be useful for such a stochastic account of uncertainty.

  • 31.
    Baresel, Christian
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Destouni, Georgia
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Gren, Ing-Marie
    The influence of metal source uncertainty on cost-effective allocation of mine water pollution abatement in catchments2006In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 78, no 2, p. 138-148Article in journal (Refereed)
    Abstract [en]

    In mine water pollution abatement, it is commonly assumed that known mine waste sites are the major pollution sources, thus neglecting the possibility of significant contribution from other old and diffuse sources within a catchment. We investigate the influence of different types of pollution source uncertainty on cost-effective allocation of abatement measures for mine water pollution. A catchment-scale cost-minimization model is developed and applied to the catchment of the river Dalalven, Sweden, in order to exemplify important effects of such source uncertainty. Results indicate that, if the pollution distribution between point and diffuse sources is partly unknown, downstream abatement measures, such as constructed wetlands, at given compliance boundaries are often cost-effective. If downstream abatement measures are not practically feasible, the pollution source distribution between point and diffuse mine water sources is critical for cost-effective solutions to abatement measure allocation in catchments. In contrast, cost-effective solutions are relatively insensitive to uncertainty in total pollutant discharge from mine water sources.

  • 32.
    Baresel, Christian
    et al.
    KTH, Superseded Departments (pre-2005), Land and Water Resources Engineering.
    Larsén, Karin
    Destouni, Georgia
    Gren, Ing-Marie
    Economic Analysis of Mine Water Pollution Abatement in a Catchment2004In: Mine Water and the Environment, ISSN 1025-9112, E-ISSN 1616-1068, Vol. 1, p. 57-68Article in journal (Refereed)
  • 33.
    Basirat, Farzad
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Hydraulic Engineering.
    CO2 leakage in a Geological Carbon Sequestration system: Scenario development and analysis.2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The aim of this project was to study the leakage of CO2 in a Geological Carbon Sequestration (GCS) system. To define the GCS system, a tool that is known as an FEP database was used. FEPs are the features, processes and events that develop scenarios for the goal of the study. Combinations of these FEPs can produce thousands of scenarios. However, among all of these scenarios, some are more important than others for leakage. The FEPs that were used as scenario developers were the formation of the liquid flow, the salinity of the formation liquid, diffusion as a process for gas bubble transport and the depth of the reservoir layer. In this study, the leakage path is considered as the presence of a fracture in sealed caprock. The fractures can be modeled using various approaches. Here, I represented the influence of fracture modeling by applying the Equivalent Continuum Method (ECM) and the Dual-Porosity and Multi-continuum methods to leakage. This study suggests that considering groundwater in the aquifer would reduce the leakage of CO2 and that a shallower formation leads to higher leakage. This study can be expanded to future studies by including external FEPs that are related to the FEPs that were used in this study.

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  • 34. Bastin, G.
    et al.
    Chotteau, Véronique
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Centre for Advanced BioProduction by Continuous Processing, AdBIOPRO.
    Vande Wouwer, A.
    Metabolic flux analysis of VERO cells under various culture conditions2021In: Processes, ISSN 2227-9717, Vol. 9, no 12, article id 2097Article in journal (Refereed)
    Abstract [en]

    Although the culture of VERO cells in bioreactors is an important industrial bioprocess for the production of viruses and vaccines, surprisingly few reports on the analysis of the flux distribution in the cell metabolism have been published. In this study, an attempt is made to fill this gap by providing an analysis of relatively simple metabolic networks, which are constructed to describe the cell behavior in different culture conditions, e.g., the exponential growth phase (availability of glucose and glutamine), cell growth without glutamine, and cell growth without glucose and glutamine. The metabolic networks are kept as simple as possible in order to avoid underdeterminacy linked to the lack of extracellular measurements, and a unique flux distribution is computed in each case based on a mild assumption that the macromolecular composition of the cell is known. The result of this computation provides some insight into the metabolic changes triggered by the culture conditions, which could support the design of feedback control strategies in fed batch or perfusion bioreactors where the lactate concentration is measured online and regulated by controlling the delivery rates of glucose and, possibly, of some essential amino acids.

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  • 35. Battaleb-Looie, S.
    et al.
    Moore, F.
    Malde, M. K.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Fluoride in groundwater, dates and wheat: Estimated exposure dose in the population of Bushehr, Iran2013In: Journal of Food Composition and Analysis, ISSN 0889-1575, E-ISSN 1096-0481, Vol. 29, no 2, p. 94-99Article in journal (Refereed)
    Abstract [en]

    The goal of this study was to estimate the daily fluoride intake for residents of Bushehr province in southern Iran by determining their exposure to fluoride through consumption of drinking water, dates and wheat. The fluoride concentration of drinking water in this region varies between 0.5 and 3.0mg/L, with an average of 1.6mg/L; and 44.4% of the drinking water exceed the guideline value of 1.5mg/L recommended by WHO. The average fluoride content of dates is 10.0mg/kg; whereas wheat roots and shoots contain an average of 30.0 and 19.0mgF-/kg, respectively. The estimated intake from drinking water is 0.12mg/kg/d for children (20kg body weight) and 0.05mg/kg/d for adults (70kg body weight). The total estimated fluoride intake (from drinking water and dates) for children is 0.17mg/kg/d. Thus, dates contribute an average 30% to the daily fluoride intake in the population. The maximum estimated fluoride intake (from dates and drinking water) for children and adults are 3.4 and 1.6 times higher, respectively, than the minimum risk level of 0.05mg/kg/d calculated by Agency for Toxic Substances and Disease Registry.

  • 36.
    Bertino, Andrea
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Water, Sewage and Waste technology.
    Study on one-stage Partial Nitritation-Anammox process in Moving Bed Biofilm Reactors: a sustainable nitrogen removal.2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the last decade, several novel and cost-effective biological nitrogen removal technologies have been developed. The discovery of anaerobic ammonium oxidation (Anammox), about 15 years ago, has resulted in new opportunities for research and development of sustainable nitrogen removal systems. Compared to conventional nitrification/denitrification, Anammox eliminates necessity of external organic carbon source, has a smaller production of excess sludge, reduces energy demand for aeration (up to 60-90%) and CO2 emissions (up to 90%). Systems based on Anammox can be of great help to comply with stricter wastewater discharge regulations and reduce environmental problems caused by nutrients discharges (e.g. eutrophication).

    This thesis investigates the partial nitritation/Anammox in one stage system under oxygen limited condi-tions (also called CANON or Deammonification) and with the Moving Bed Biofilm Reactor (MBBR™) technology. Anammox process coupled with partial nitritation can be particularly suitable to treat ammo-nium-rich wastewater with low content of biodegradable organic matter, such as the reject water from dewatering of digested sludge, which is usually recirculated back to the main stream of wastewater treat-ment plants, accounting for the 15-20% of the total nitrogen load.

    Partial nitritation/Anammox process was successfully tested on a pilot plant scale for four months at 25°C, in a 200 L Continuous Stirred Tank Reactor (CSTR), filled with 40% of Kaldnes media (model K1). At an Ammonium Surface Load (ASL) of 3.45 gN m-2d-1, the removal rate was about 2.85 gN m-2d-1. Removal efficiencies of 95%, 85% and 83% were respectively achieved for NH4+-N, inorganic nitrogen, and Total Nitrogen (TN). Bacteria activity was followed by batch tests such as Specific Anammox Activity (SAA), Oxygen Uptake Rate (OUR) and Nitrate Uptake Rate (NUR), which revealed an increase in activi-ty for Nitrosomonas and Anammox bacteria within the biofilm. Dissolved oxygen concentration in the bulk liquid was a crucial parameter, whereas pH and conductivity turned out to be two useful monitoring tools.

    Two laboratory-scale reactors were previously run for two months each, in order to evaluate the one-stage partial nitritation/Anammox process with a lower ASL. One reactor was fed with diluted reject water, whereas the other one treated the effluent from UASB (Up-flow Anaerobic Sludge Blanket) reactor after sand filtration. Fairly good efficiency (>75%) were reached but, however, in the last case the low ammo-nium nitrogen load could represent a problem for a stable full-scale installation and long-term growth of Anammox bacteria.

    Some suggestions for full-scale implementation and further research are proposed in the last chapter of this master thesis.

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  • 37.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology. KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Mukherjee, A. B.
    Management of arsenic contaminated groundwater in the Bengal Delta Plain2017In: Conflict Management of Water Resources, Informa UK Limited , 2017, p. 308-348Chapter in book (Other academic)
    Abstract [en]

    In the first half of the 13th century, St. Francis of Assisi (1182-1226) predicted the acute importance of water, which he defined as pretiosa (Cascetta, 1995). Unfortunately, the world has forgotten this caveat and in recent years, the importance of water resources is finally receiving greater attention in our daily lives. This is the result of rising demands, declining availability, as well as treatment costs incurred as the result of pollution from industrial and natural sources.

  • 38. Bhowmick, S.
    et al.
    Nath, B.
    Halder, Dipti
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Biswas, Ashis
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Majumder, S.
    Mondal, P.
    Chakraborty, S.
    Nriagu, J.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Iglesias, M.
    Roman-Ross, G.
    Guha Mazumder, D.
    Bundschuh, J.
    Chatterjee, D.
    Arsenic mobilization in the aquifers of three physiographic settings of West Bengal, India: Understanding geogenic and anthropogenic influences2013In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 262, p. 915-923Article in journal (Refereed)
    Abstract [en]

    A comparative hydrogeochemical study was carried out in West Bengal, India covering three physiographic regions, Debagram and Chakdaha located in the Bhagirathi-Hooghly alluvial plain and Baruipur in the delta front, to demonstrate the control of geogenic and anthropogenic influences on groundwater arsenic (As) mobilization. Groundwater samples (n=90) from tube wells were analyzed for different physico-chemical parameters. The low redox potential (Eh=-185 to -86mV) and dominant As(III) and Fe(II) concentrations are indicative of anoxic nature of the aquifer. The shallow (&lt;100m) and deeper (&gt;100m) aquifers of Bhagirathi-Hooghly alluvial plains as well as shallow aquifers of delta front are characterized by Ca2+HCO3 - type water, whereas Na+ and Cl- enrichment is found in the deeper aquifer of delta front. The equilibrium of groundwater with respect to carbonate minerals and their precipitation/dissolution seems to be controlling the overall groundwater chemistry. The low SO4 2- and high DOC, PO4 3- and HCO3 - concentrations in groundwater signify ongoing microbial mediated redox processes favoring As mobilization in the aquifer. The As release is influenced by both geogenic (i.e. geomorphology) and anthropogenic (i.e. unsewered sanitation) processes. Multiple geochemical processes, e.g., Fe-oxyhydroxides reduction and carbonate dissolution, are responsible for high As occurrence in groundwaters.

  • 39. Bhowmick, Subhamoy
    et al.
    Halder, Dipti
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Kundu, Amit Kumar
    Saha, Debasree
    Iglesias, Monica
    Nriagu, Jerome
    Mazumder, Debendra Nath Guha
    Roman-Ross, Gabriela
    Chatterjee, Debashis
    Is Saliva a Potential Biomarker of Arsenic Exposure?: A Case-Control Study in West Bengal, India2013In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 47, no 7, p. 3326-3332Article in journal (Refereed)
    Abstract [en]

    Saliva is a biological fluid that has not been used extensively as a biomonitoring tool in epidemiological studies. This study presents the arsenic (As) concentrations in saliva and urine samples collected from populations of West Bengal, India who had been previously exposed to high As levels in their drinking water. We found a significant (p < 0.05) association between the Log transformed Daily Ingestion of As (mu g day(-1)) and the As concentration in saliva (r = 0.68). Additionally, As concentration of saliva and urine also had a significant positive correlation (r = 0.60, p < 0.05). Male participants, smokers, and cases of skin lesion were independently and significantly associated with an increase in salivary As. Thus our findings show that saliva is a useful biomarker of As exposure in the study population. The study also advocates that measurement of the forms of As in saliva may additionally provide insight into the internal dose and any individual differences in susceptibility to As exposure.

  • 40.
    Biswas, Ashis
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Majumder, Santanu
    Neidhardt, Harald
    Halder, Dipti
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bhowmick, Subhamoy
    Mukherjee-Goswami, Aishwarya
    Kundu, Amit
    Saha, Debasree
    Berner, Zsolt
    Chatterjee, Debashis
    Groundwater chemistry and redox processes: Depth dependent arsenic release mechanism2011In: APPLIED GEOCHEMISTRY, 2011, Vol. 26, no 4, p. 516-525Conference paper (Refereed)
    Abstract [en]

    Patchy occurrences of elevated As are often encountered in groundwater from the shallow aquifers (<50 m) of the Bengal Delta Plain (BDP). A clear understanding of various biogeochemical processes, responsible for As mobilization, is very important to explain this patchy occurrence and thus to mitigate the problem. The present study deals with the periodical monitoring of groundwater quality of five nested piezometeric wells between December 2008 and July 2009 to investigate the temporal changes in groundwater chemistry vis-a-vis the prevalent redox processes in the aquifer. Geochemical modeling has been carried out to identify key phases present in groundwater. A correlation study among different aqueous redox parameters has also been performed to evaluate prevailing redox processes in the aquifer. The long term monitoring of hydrochemical parameters in the multilevel wells together with hydrogeochemical equilibrium modeling has shown more subtle differences in the geochemical environment of the aquifer, which control the occurrence of high dissolved As in BDP groundwater. The groundwater is generally of Ca-HCO3 type. The dissolved As concentration in groundwater exceeded both WHO and National drinking water standard (Bureau of Indian Standards; BIS, 10 mu g L-1) throughout the sampling period. The speciation of As and Fe indicate persistent reducing conditions within the aquifer [As(III): 87-97% of As-T and Fe(II): 76-96% of Fe-T]. The concentration of major aqueous solutes is relatively high in the shallow aquifer (wells A and B) and gradually decreases with increasing depth in most cases. The calculation of SI indicates that groundwater in the shallow aquifer is also relatively more saturated with carbonate minerals. This suggests that carbonate mineral dissolution is possibly influencing the groundwater chemistry and thereby controlling the mobilization of As in the monitored shallow aquifer. Hydrogeochemical investigation further suggests that Fe and/or Mn oxyhydroxide reduction is the principal process of As release in groundwater from deeper screened piezometric wells. The positive correlations of U and V with As. Fe and Mn indicate redox processes responsible for mobilization of As in the deeper screened piezometric wells are possibly microbially mediated. Thus, the study advocates that mobilization of As is depth dependent and concentrations of As in groundwater depends on single/combined release mechanisms.

  • 41.
    Blix, Annika
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Enhancing the capacity of seeds as turbidity removal agents in water treatment.: A Minor Field Study.2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The aim of this master’s thesis was to investigate if defattening of Parkinsonia aculeata (in

    swahili “mkeketa”) and Vigna unguiculata (in swahili “choroko”) would enhance the capacity of the seed’s properties in removing suspended particles from surface water. The seeds are used in local traditional treatment of drinking water in Tanzania. The aim was also to investigate the possibility to reduce high concentrations of fluoride with the seeds. The seeds contain proteins that act as coagulants. Coagulated particulate matter can be flocculated and separated from the water. A purification of the coagulants by defattening was expected to enhance the coagulating capacity. Experiments were conducted in jar-tests with dosages of coagulant solutions of undefattening and defattened seed solutions and alum (aluminium sulphate). The experiments showed that both Parkinsonia aculeata and Vigna unguiculata seeds can compete with alum in drinking water treatment of surface water, reaching the same or better final results in turbidity removal. Both seeds also produce less sludge volumes than alum and functions in turbidity removal together with alum. The seeds may be used as coagulant aids to reduce the usage of chemicals and sludge production. They were not able to clarify turbid waste water and did not reduce high concentrations of fluoride in groundwater. Further, the turbidity-removal capacity of the coagulants had reduced capacities in water with low pH-values.

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  • 42.
    Blomkvist, Pär
    et al.
    Division of Organization and Management, Mälardalen University, Högskoleplan 1, 722 20, Västerås, Sweden.
    Karpouzoglou, Timon
    KTH, School of Architecture and the Built Environment (ABE), Philosophy and History, History of Science, Technology and Environment.
    Nilsson, David
    KTH, School of Architecture and the Built Environment (ABE), Philosophy and History, History of Science, Technology and Environment.
    Wallin, Jörgen
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Entrepreneurship and alignment work in the Swedish water and sanitation sector2023In: Technology in society, ISSN 0160-791X, E-ISSN 1879-3274, Vol. 74, article id 102280Article in journal (Refereed)
    Abstract [en]

    Water and sewage (WS) systems are, like most grid based infrastructural systems, often centralised and hierarchical and the end user has almost no possibility to influence the technical standards, business models or system architecture. The preferred method for connecting new areas to the grid are underground water pipes and gravity flow for sewage. Thus, the WS system is “tightly coupled”. It is hard to change and conservative in its system culture, exhibiting a strong “momentum” or “path dependence”. In this article we investigate an unusual case in the development of WS-systems. As a rule, WS-systems, as most infrastructural systems, develop gradually through incremental innovations, and system owners/utilities traditionally build their systems “from the inside out”. In our case, we investigate a situation where the end users took the initiative to connect a residential area, Aspvik, part of the municipality of Värmdö, outside Stockholm, Sweden, to the municipal grid and thus expand the WS-system, not from the inside out, but from the outside in. Furthermore, we highlight another unusual feature: the role of a resident that acted as the “entrepreneur” in this process of WS-system expansion. The entrepreneur had unique trust building abilities in the local community, which the regime actor (the WS utility), could not match. Historically, inventor-entrepreneurs have been common, acting as “system builders” in the establishment phase of new infrastructural systems. However, entrepreneurs outside the regime are not common in the WS sector. Although atypical in mature WS systems in developed countries, these types of local initiatives or hybrid solutions are common in developing countries. In this article, we argue that there are lessons to be learnt from our case, when dealing with system expansion processes both inside and outside the Global North.

  • 43.
    Boberg, Björn
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Hydraulic Engineering.
    Holm, David
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Hydraulic Engineering.
    FEM modeling of concrete gravity dams.2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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  • 44.
    Boberg, Molly
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Selander, Märta
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Systematic and Automatized Hydrogeological Data Capturing for Provision of Safe Drinking Water in Daudkandi, Bangladesh2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Arsenic-contaminated drinking water exposes ~230 million people worldwide to increased risks of several diseases and is considered one of the greatest threats to public health. In Bangladesh, arsenic-contaminated water has been declared the largest poisoning of a population in history, where 39 million people are exposed to arsenic levels above the WHO guidelines (>10 μg/L). Drinking water is mainly provided by tube-wells installed by local drillers and the majority are located in aquifers with high arsenic levels. The major challenges of identifying arsenic-safe aquifers consist of a lack of a common tool for quality assurance of hydrogeological data, post-processing of the data, and a possibility to forward analyzed data to national and local stakeholders. Therefore, the purpose of this study was to investigate the potential of applying a digital solution for collecting and managing hydrogeological data in a quality assured platform. This study was a pilot-project in the sub-district Daudkandi, Bangladesh in collaboration with the KTH-International Groundwater Research Group. To fulfill the purpose, a method was developed for systematic and automated data capturing of hydrogeological information in GeoGIS, an advanced software that proved to be an efficient tool for visualizing hydrogeological data. The results show that collecting a few field data in a systematic and automated way is helpful for interpreting aquifer sequences and will enable better prerequisites for targeting safe aquifers and installing safe tube-wells. Conclusions are that the integration of a digital platform as a decision tool may significantly improve arsenic mitigation strategies. Furthermore, providing information to public and private sectors in Bangladesh would increase the transparency of hydrogeological conditions and may help improve safe water access to high arsenic areas of Bangladesh. 

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  • 45.
    Borzooei, Sina
    et al.
    IVL Swedish Environmental Research Institute, PO Box 210 60, Stockholm SE-100 31, Sweden, PO Box 210 60; BIOMATH, Department of Data Analysis and Mathematical Modelling, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Gent, Belgium, Coupure links 653.
    Scabini, Leonardo
    São Carlos Institute of Physics, University of São Paulo, 13560-970, São Carlos - SP, Brazil, SP; KERMIT, Department of Data Analysis and Mathematical Modelling, Ghent University, Coupure links 653, 9000 Gent, Belgium, Coupure links 653.
    Miranda, Gisele
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Computational Science and Technology (CST).
    Daneshgar, Saba
    BIOMATH, Department of Data Analysis and Mathematical Modelling, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Gent, Belgium, Coupure links 653; CAPTURE, Centre for Advanced Process Technology for Urban Resource Recovery, Frieda Saeysstraat 1, 9000 Gent, Belgium, Frieda Saeysstraat 1.
    Deblieck, Lukas
    Pantarein Water, Egide Walschaertsstraat 22L, 2800 Mechelen, Belgium, Egide Walschaertsstraat 22L.
    Bruno, Odemir
    São Carlos Institute of Physics, University of São Paulo, 13560-970, São Carlos - SP, Brazil, SP.
    De Langhe, Piet
    Pantarein Water, Egide Walschaertsstraat 22L, 2800 Mechelen, Belgium, Egide Walschaertsstraat 22L.
    De Baets, Bernard
    KERMIT, Department of Data Analysis and Mathematical Modelling, Ghent University, Coupure links 653, 9000 Gent, Belgium, Coupure links 653.
    Nopens, Ingmar
    BIOMATH, Department of Data Analysis and Mathematical Modelling, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Gent, Belgium, Coupure links 653; CAPTURE, Centre for Advanced Process Technology for Urban Resource Recovery, Frieda Saeysstraat 1, 9000 Gent, Belgium, Frieda Saeysstraat 1.
    Torfs, Elena
    BIOMATH, Department of Data Analysis and Mathematical Modelling, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Gent, Belgium, Coupure links 653; Université Laval, 1065 avenue de la Médecine, Québec G1V 0A6, QC, Canada, 1065 avenue de la Médecine.
    Evaluation of activated sludge settling characteristics from microscopy images with deep convolutional neural networks and transfer learning2024In: Journal of Water Process Engineering, E-ISSN 2214-7144, Vol. 64, article id 105692Article in journal (Refereed)
    Abstract [en]

    Timely assessment and prediction of changes in microbial compositions leading to activated sludge settling problems, such as filamentous bulking (FB), can reduce water resource recovery facilities (WRRFs) upsets, operational challenges, and negative environmental impacts. This study presents a computer vision approach to assess activated sludge-settling characteristics based on Microscopy Images (MIs). We utilize MIs to train deep convolutional neural networks (CNN) using transfer learning to investigate the morphological properties of flocs and filaments. The methodology was tested on the offline MI dataset collected over two years at a full-scale industrial WRRF in Belgium. Various CNN architectures were tested, including Inception v3, ResNet18, ResNet152, ConvNeXt-nano, and ConvNeXt-S. The sludge volume index (SVI) was used as the final prediction variable, but the method can be easily adjusted to predict any other settling metric of choice. The best-performing CNN, ConvNeXt-nano, could predict SVI values with MAE (37.51 ± 4.02), MTD (11.65 ± 1.94), MAPE (0.18 ± 0.02), and R2 (0.75 ± 0.05). The model was tested in real-life FB events, where it identified early indicators of bulking by predictive surges in SVI values. We used an explainable AI technique, Eigen-CAM, to discover key morphological indicators of sludge bulking transitions. The findings highlight the SVI multimodality issue, where SVI readings as a unidimensional metric could not capture delicate shifts from good to poor sludge settling, while the model detected these subtle changes. The key morphological attributes of threshold conditions leading to FB were identified, which can provide actionable insight for preemptive WRRF management.

  • 46.
    Bottacin-Busolin, Andrea
    et al.
    Univ Padua, Dept Hydraul Maritime Environm & Geotech Engn, I-35131 Padua, Italy.
    Marion, Andrea
    Univ Padua, Dept Hydraul Maritime Environm & Geotech Engn, I-35131 Padua, Italy.
    Zaramella, Mattia
    Univ Padua, Dept Hydraul Maritime Environm & Geotech Engn, I-35131 Padua, Italy.
    Modellazione a tempi di residenza del trasporto di soluti nei corsi d'acqua: Applicazione al fiume Yarqon, Israele2008Conference paper (Other academic)
    Abstract [it]

    Il trasporto di soluti nei corsi d’acqua è controllato dall’idrodinamica superficiale e da scambi di massa con distinte zone di ritenzione. La propagazione a valle delle sostanze trasportate è generalmente ritardata dall’immagazzinamento temporaneo in zone morte superficiali, tipicamente zone vegetate o sacche di ritenzione laterali, e nei sedimenti sottostanti, nella cosiddetta zona iporeica. In questo articolo viene presentato un modello concettuale per il trasporto di soluti nei corsi d’acqua (STIR, Solute Transport In Rivers) nel quale i singoli processi di scambio sono rappresentati separatamente da una probabilità di “uptake” e da un’appropriata distribuzione dei tempi di residenza. Ciò rende il modello flessibile e modulare, e consente di incorporare l’effetto di una varietà di processi d’immagazzinamento e reazioni chimiche in modo dettagliato. La capacità del modello di rappresentare situazioni reali è qui dimostrata dall’applicazione al fiume Yarqon, in Israele.

  • 47. Brandimarte, L.
    et al.
    D'Odorico, P.
    Montanari, A.
    A probabilistic approach to the analysis of contraction scour2006In: Journal of Hydraulic Research, Vol. 44, no 5, p. 654-662Article in journal (Refereed)
  • 48. Brandimarte, L.
    et al.
    Montanari, A.
    Briaud, J. -L
    D'Odorico, P.
    Stochastic flow analysis for predicting river scour of cohesive soils2006In: Journal of Hydraulic Engineering, Vol. 132, no 5, p. 493-500Article in journal (Refereed)
  • 49.
    Brandner, Hanna
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Hydraulic Engineering.
    Idenitfying the Influential Factors of the Temporal Variation of Water Consumption: A Case Study using Multiple Linear Regression Analysis2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis is a part of the water development project conducted by Svenskt Vatten, which is the Swedish Water and Wastewater Association (SWWA) as well as Tyréns, a consultancy company with offices based in Stockholm, Sweden. Prior to this thesis work, a quality assessment was conducted for some of the locations provided by municipalities in Sweden. This thesis builds upon the revised water consumption data, and also continues to work with validating and modifying the water measurement data in order to proceed with the next step of the water development project, which is to identify any trends in the temporal variation of water consumption. The main objective of this thesis work is to investigate the influence of climatic, time-related and categorical factors on water consumption data collected for different regions in Sweden, and includes a number of different sectors such as residential, industrial and agricultural water user sectors. For the analysis of data, spectral analysis and sinusoidal modelling will be applied in order to find the periodicity of the data, and then simulate the fitted sinusoidal equation to the observed water consumption data for the hourly interval period. Multiple linear regression analysis is then used to assess what independent variables such as climate, time-related and categorical variables can explain the variation in water consumption over hourly and daily periods of time. 

    Spectral analysis identifies high peaks in the spectral density of the data at 12 and 24 hour cycles, for the hourly water consumption data. For the total daily consumption of water, there is a peak at 7 days, which clarifies that there is a weekly pattern occurring throughout the year. The results from the simple linear regression analysis, where the linear relationship between temperature and water consumption was determined, reveals that the water consumption tends to increase within an increasing temperature, where in Lönashult, Alvesta municipality the water demand increased by 5.5% with every 2 ºC rise in temperature, at a threshold of 12 ºC. For Kalix municipality the three areas selected have around 1-2 % increase in water demand with every 2 ºC rise in temperature for the period of May to December. In Gothenburg, areas that were mixed villa areas or areas with summer homes there was a rise of around 2-12 % in water demand, however areas that are situated in the inner city Gothenburg, or that have majority student housing, the water consumption tends to decrease by 2-7% in water demand with every 2 ºC rise in temperature, with a threshold of 12 ºC.

    In multiple regression analysis, the hourly water consumption results in adjusted R2 values were in the range from 0.58 to 0.87 (58-87%) for the best model approach and therefore has a significant relationship between water consumption and the explanatory variables chosen for this study. For the daily water consumption, the adjusted R2 values were in the range of 0.22-0.83 (22-83%).  The adjusted R2 values are lower for certain areas and can be explained by a number of factors, such as the different variables used for the daily water consumption analysis, as variables that explain more the periodicity of the data such as the sinusoidal fitted variable and hourly or night/day changes in consumption are not included. As well as this, not all independent variables such as the climate variables were available or complete for particular time periods, and also errors in the data can lead to a significantly lower R2 value. 

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  • 50. Briaud, J. -L
    et al.
    Brandimarte, L.
    Wang, J.
    D’Odorico, P.
    Probability of scour depth exceedance owing to hydrologic uncertainty2007In: Georisk, Vol. 1, no 2, p. 77-88Article in journal (Refereed)
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