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  • 1.
    Ahmad, Arslan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Arsenic in Drinking Water: Is 10 μg/L a Safe Limit?2019In: Current Pollution Reports, ISSN 2198-6592, Vol. 5, no 1Article in journal (Refereed)
  • 2.
    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. 

  • 3.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Mukherjee, A.
    University of Texas at Austin, TX, USA and Albert Geological Survey, Edmonton, AB, Canada.
    Mukherjee, A. B.
    University of Helsinki, Helsinki, Finland.
    Arsenic in Groundwater of India2011In: Encyclopedia of Environmental Health, Elsevier Inc. , 2011, p. 150-164Chapter in book (Other academic)
  • 4.
    Björk, Folke
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Sederholm, Bror
    Trägårdh, Jan
    RISE Cement- och betonginstitutet.
    Dränering av fukt i betong genom elektrokemisk metodik (elektroosmos) 2018Report (Other academic)
    Abstract [sv]

    Syftet med detta projekt är att studera funktionen av elektroosmos som åtgärd mot fukt-problem i byggnader i Sverige samt att utifrån detta ge rekommendationer kring om och i så fall när det är lämpligt/olämpligt att använda metodiken under de varierande fuktighets-förhållanden som vanligtvis råder i Sverige.

    I projektet har vi gjort en litteraturstudie, en modellering av fysikaliska processer, studie-besök i byggnader med installationer för elektroosmos och mätningar av fukt i en källarvägg där en installation för elektroosmos blivit gjord.

    Vi ser metoden elektroosmos som en möjlighet för att hantera fuktproblem i grunder. Det behövs dock en del av utveckling både kring tekniken för metoden och kring vad som ska kunna förväntas av den.

    Det behövs bättre möjligheter att kunna förutsäga att metoden kommer att fungera i ett visst fall. Att inte kunna förutsäga detta bör vara ett bekymmer för dem som marknadsför metoden.

    Elektroosmos kräver höga fuktnivåer för att fungera. Torkning ned till under kritiska fuktnivåer kräver komplettering med andra torkmetoder. Det krävs en tydlighet kring hur detta ska lösas.

    Det behövs en bättre förståelse kring hur elektroderna ska placeras för bästa funktion.

    Fuktvandring i jorden kan ha stor betydelse för processen i praktiken. Det är idé att undersöka om detta kan användas för att utveckla metoden.

    Det behövs klara regler kring hur elinstallationen ska utformas på ett säkert sätt.

    Eftersom jontransporten i betongen är av ganska liten omfattning så tror vi inte att elektroosmos kommer att påverka, eller skada, betongens egenskaper på lång sikt.

  • 5. Blum, K. M.
    et al.
    Gallampois, C.
    Andersson, P. L.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Agnieszka
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Haglund, P.
    Comprehensive assessment of organic contaminant removal from on-site sewage treatment facility effluent by char-fortified filter beds2019In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 361, p. 111-122Article in journal (Refereed)
    Abstract [en]

    To remove organic contaminants from wastewater using cost-efficient and currently existing methods, our study investigated char-fortified filter beds for on-site sewage treatment facilities (OSSFs) in a long-term field setting. OSSFs are commonly used in rural and semi-urban areas worldwide to treat wastewater when municipal wastewater treatment is not economically feasible. First, we screened for organic contaminants with gas chromatography and liquid chromatography mass spectrometry-based targeted and untargeted analysis and then we developed quantitative structure-property relationship models to search for key molecular features responsible for the removal of organic contaminants. We identified 74 compounds (24 confirmed by reference standards) including plasticizers, UV stabilizers, fragrances, pesticides, surfactant and polymer impurities, pharmaceuticals and their metabolites, and many biogenic compounds. Sand filters that are used as a secondary step after the septic tank in OSSFs could remove hydrophobic contaminants. The addition of biochar significantly increased the removal of these and a few hydrophilic compounds (Wilcoxon signed-rank test, α = 0.05). Besides hydrophobicity-driven sorption, biodegradation was suggested to be the most important removal pathway in this long-term field application. However, further improvements are necessary to remove very hydrophilic contaminants as they were not removed with sand and biochar-fortified sand.

  • 6.
    Braun, Sabina
    et al.
    Swedish University of Agricultural Sciences, Department of Soil and Environment.
    Warrinnier, Ruben
    KU Leuven, Belgium.
    Börjesson, Gunnar
    Swedish University of Agricultural Sciences, Department of Soil and Environment.
    Ulén, Barbro
    Swedish University of Agricultural Sciences, Department of Soil and Environment.
    Smolders, Erik
    KU Leuven, Belgium.
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Assessing the ability of soil tests to estimate labile phosphorus in agricultural soils: Evidence from isotopic exchange2019In: Geoderma, ISSN 0016-7061, E-ISSN 1872-6259, Vol. 337, p. 350-358Article in journal (Refereed)
    Abstract [en]

    Efficient phosphorus (P) fertilization strategies are essential for intensive crop production with minimal negative environmental impacts. A key factor in sustainable P use is assessment of the plant available soil P pool using soil P tests. This study determined isotopically exchangeable P after six days of reaction with 33PO4 (P-E (6 d)) to determine how accurately two commonly used P tests, Olsen and AL (acid ammonium acetate lactate) can quantify the amount of labile P. Soil samples were taken from both highly P-amended and unamended plots at six sites within the Swedish long-term soil fertility experiments. According to P K-edge XANES spectroscopy, the P speciation was dominated by Al-bound P and organic P, with additional contributions from Fe-bound P and Ca phosphates in most soils. The results showed that the AL test overestimated P-E (6 d) by a factor of 1.70 on average. In contrast, the Olsen test underestimated P-E (6 d), with the mean ratios of P-Olsen to P-E (6 d) being 0.52 for high-P and 0.19 for low-P soils. The 33P/31P ratio in the Olsen extract of a 33PO4 spiked soil was closer to that of a 0.005 mol L−1 CaCl2 soil extract than the corresponding ratio in the AL extract, suggesting that AL extraction solubilized more non-labile P. In conclusion, the AL and Olsen methods are not suitable for direct quantification of the isotopically exchangeable soil P pool after 6 days of equilibration. However, based on the results, Olsen may be superior to AL for classification of soil P status, due to its even performance for calcareous and non-calcareous soils and lower extraction of non-labile P.

  • 7. Bundschuh, Jochen
    et al.
    Maity, Jyoti Prakash
    Mushtaq, Shahbaz
    Vithanage, Meththika
    Seneweera, Saman
    Schneider, Jerusa
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Khan, Nasreen Islam
    Hamawand, Ihsan
    Guilherme, Luiz R. G.
    Reardon-Smith, Kathryn
    Parvez, Faruque
    Morales-Simfors, Nury
    Ghaze, Sara
    Pudmenzky, Christa
    Kouadio, Louis
    Chen, Chien-Yen
    Medical geology in the framework of the sustainable development goals2017In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 581, p. 87-104Article in journal (Refereed)
    Abstract [en]

    Exposure to geogenic contaminants (GCs) such as metal(loid)s, radioactive metals and isotopes as well as transuraniums occurring naturally in geogenic sources (rocks, minerals) can negatively impact on environmental and human health. The GCs are released into the environment by natural biogeochemical processes within the near-surface environments and/or by anthropogenic activities such as mining and hydrocarbon exploitation as well as exploitation of geothermal resources. They can contaminate soil, water, air and biota and subsequently enter the food chain with often serious health impacts which are mostly underestimated and poorly recognized. Global population explosion and economic growth and the associated increase in demand for water, energy, food, and mineral resources result in accelerated release of GCs globally. The emerging science of "medical geology" assesses the complex relationships between geo-environmental factors and their impacts on humans and environments and is related to the majority of the 17 Sustainable Development Goals in the 2030 Agenda of the United Nations for Sustainable Development. In this paper, we identify multiple lines of evidence for the role of GCs in the incidence of diseases with as yet unknown etiology (causation). Integrated medical geology promises a more holistic understanding of the occurrence, mobility, bioavailability, bio-accessibility, exposure and transfer mechanisms of GCs to the food-chain and humans, and the related ecotoxicological impacts and health effects. Scientific evidence based on this approach will support adaptive solutions for prevention, preparedness and response regarding human and environmental health impacts originating from exposure to GCs.

  • 8.
    De Colle, Mattia
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Jönsson, Pär
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Processing.
    Karasev, Andrey
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Processing.
    Gauffin, Alicia
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Renman, Agnieszka
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    The Use of High-Alloyed EAF Slag for the Neutralization of On-Site Produced Acidic Wastewater: The First Step Towards a Zero-Waste Stainless-Steel Production Process2019In: Applied Sciences, ISSN 2076-3417, Vol. 9Article in journal (Refereed)
    Abstract [en]

    Recycling of steelmaking slags has well-established applications, such as their use in cement, asphalt, or fertilizer industries. Although in some cases, such as the electric arc furnace (EAF) high-alloyed stainless-steel production, the slag’s high metal content prevents its use in such applications. This forces companies to accumulate it as waste. Using concepts such dematerialization, waste management, industrial symbiosis, and circular economy, the article drafts a conceptual framework on the best route to solving the landfilling issue, aiming at a zero-waste process re-design. An experimental part follows, with an investigation of the use of landfill slag as a substitute of limestone for the neutralization of acidic wastewater, produced by the rinsing of steel after the pickling process. Neutralization of acidic wastewater with both lime and slag samples was performed with two different methods. Two out of four slag samples tested proved their possible use, reaching desired pH values compared to lime neutralizations. Moreover, the clean waters resulting from the neutralizations with the use of both lime and slag were tested. In terms of hazardous element concentrations, neutralization with slag yielded similar results to lime. The results of these trials show that slag is a potential substitute of lime for the neutralization of acidic wastewater.

  • 9.
    Earon, Robert
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Groundwater resources in hard rock coastal terrains: Insights into heterogeneity and spatial variability2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Challenges regarding water security in hard rock coastal regions with limited soil cover are: a seasonal absence of recharge during times of peak residency, heterogeneity and variability of the fracture network, close proximity to saline water sources and spatially inconsistent storage and extraction. In areas where it is not feasible to connect residents to municipal water systems, a better understanding of the resilience of reservoirs is needed. The purpose of this study is to investigate and describe the spatial nature of hydraulic data in these types of terrains and present several novel GIS-based groundwater tools with the intent of increasing local water security and aiding in sustainable water resources management. Methods used in this study include groundwater balance modelling and conceptual groundwater storage modelling, as well as a combination of parametric and non-parametric statistical methods such as ANOVA, PCA, correlation and semivariogram analyses. Specific capacity estimates from the Geological Survey of Sweden’s well archive grouped by age or rock type showed very little autocorrelation and in assumed homogeneous geological regions showed statistically significant differences when arbitrarily grouped along a lineament. Estimates of kinematic porosity based on surface fracture data were found have statistically significant correlations with the well data. A GIS-based multivariate prediction tool for assessing Groundwater Resources Potential (GRP) was found to have statistically significant correlations with well data. The GRP method was then combined with a conceptual groundwater storage model and was subsequently found to have statistically significant correlations with chloride concentrations in well quality tests. The storage model was found to have a spatially-dependent sensitivity, meaning that different assumptions within the model had varying effects on the model depending on the geological settings. Incorporating the storage model into a spatial groundwater balance model was then compared with groundwater level time series data over a period of two years, where it was found to have a good explanative capacity and RMSE values of the storage ratio (0.06 to 0.34). Additionally, a soil depth model was developed, tested and found to produce promising results in regions with frequent rock outcrops, where up to 86% of estimates were within 2 m of actual soil depths. Conclusions from this study illustrate the need for a spatial approach to groundwater resources in these types of terrains, and demonstrate a strong potential of several new tools for quantity, capacity and vulnerability estimates to increase water security in a changing climate.

  • 10.
    Earon, Robert
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Hydraulic heterogeneity and its impact on kinematic porosity in Swedish coastal terrains2018In: Engineering Geology, ISSN 0013-7952, E-ISSN 1872-6917, Vol. 245Article in journal (Refereed)
    Abstract [en]

    Hydrogeology in crystalline rock aquifers is often problematic due to the heterogeneity and anisotropy in thefracture network. Kinematic porosity of the host rock is exceedingly important for municipal decision makers inassessing sustainably extractable water supply volumes and assessing contaminant transport behavior within thematrix. This study explores heteroscedasticity in the hydrogeological characteristics of the fracture network andestimation of kinematic porosity from superficial fracture measurements. Estimates were based on the geometricalproperties of the fractures including: fracture frequency, aperture and orientation. The estimates wereadjusted for aperture changes with depth, connectivity of the fracture network, fracture continuity and measurementorientation bias. The results were compared with well archive data and correlations were found to besignificant with more than 95% confidence. Erratic behaviour of well data relative to fracture measurementsindicates that well orientation with respect to the fracture network gives incomplete hydrogeological data.Spatial heterogeneity of the bedrock was examined using spatial statistics and geographic information systems.The results from the spatial statistical analyses of well data showed that the heterogeneity within the bedrock issufficiently high that spatial correlations cease to exist in nearly all investigated rock types at distances greaterthan 500 m, and in some rocks, particularly sedimentary gneisses, no spatial correlations were observed.Arbitrarily grouped samples with similar geology and topography showed evidence of non-stationary variance.Results indicate that regional generalizations based on sparse point measurements are highly error prone andpotential exists in complementary field-based estimates.

  • 11.
    Earon, Robert
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Integrating storage and spatial variability into regional groundwater balances: Moving towards water security in hard rock coastal areasManuscript (preprint) (Other academic)
    Abstract [en]

    In terrains with limited soil cover and groundwater storage, groundwater resource management is governed by the spatial nature of storage, recharge and extraction. Local soils may act as important groundwater reservoirs for residents which have no other feasible water supply. A novel groundwater balance methodology is presented which accounts for the spatial distribution of storage and extraction. Existing topographical and geological databases as well as well data were used to construct a conceptual model of the groundwater system, assuming stratigraphy based on typical geology. The method is implemented in a geographic information systems environment and allows for variable climate and land use scenarios.

    Several scenarios were examined with this method, demonstrating that on a regional scale average reservoir volumes meet demand but at the local levels depletion of reservoirs may be experienced. Groundwater level drawdown in excess of 50% of the projected reservoir storage were seen, particularly near the coast. Soil-filled valleys may act as local hydraulic barriers, preventing contamination from saline water provided no direct hydraulic connection is present. The method demonstrates the importance of a spatial approach in managing groundwater resources, and shows promise as a tool for planners in increasing water security.

  • 12.
    Earon, Robert
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    The importance of a spatial approach to water resources management in heterogeneous regionsManuscript (preprint) (Other academic)
    Abstract [en]

    Limited groundwater storage in recently glaciated terrains with frequent hard, crystalline bedrock outcrops poses challenges for groundwater resources management. Due to often-limited economic resources allocated to groundwater investigations in areas where drinking water is primarily supplied by private wells, heuristic solutions such as groundwater balances with built-in limitations of storage may serve a vital role in improving water security. This study investigates the use of a conceptual groundwater balance model and the use of a conceptual-statistical reservoir vulnerability model with this aim. A limited storage, GIS-based groundwater balance model using existing databases was applied to an area outside of Stockholm, Sweden with existing groundwater level measurement data. The spatial model showed improved performance over existing S-Hype model estimates of groundwater levels currently used in groundwater resources management by the Geological Survey of Sweden, even without local calibration. Differences between two wells with time series data showed evidence of strong influence due to in-situ geological conditions. Groundwater vulnerability estimates correlated significantly with chloride measurements from an existing chemistry database. The performance of the conceptually-based spatial groundwater balance supports the use of the approach as an aid for municipal planners and decision-makers in moving towards sustainable groundwater resources planning and improving water security in areas with limited storage and a large number of dispersed, private wells.

  • 13.
    Hamisi, Rajabu
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Agnieszka
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Performance of an On-Site Wastewater Treatment System Using Reactive Filter Media and a Sequencing Batch Constructed Wetland2019In: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 11, no 11, article id UNSP 3172Article in journal (Refereed)
    Abstract [en]

    Many on-site wastewater treatment systems, such as soil treatment systems, are not sustainable in terms of purification efficiency, nutrient recycling potential, and economics. In this case study, a sequencing batch constructed wetland (SBCW) was designed and added after a package treatment plant (PTP) using reactive filter media for phosphorus (P) removal and recycling. The treatment performance of the entire system in the start-up phase and its possible applicability in rural areas were investigated. Raw and treated effluents were sampled during a period of 25 weeks and analyzed for nitrogen, phosphorus, BOD7, and bacteria. Field measurements were made of wastewater flow, electrical conductivity, oxygen, and temperature. The entire system removed total-P and total inorganic nitrogen (TIN) by 83% and 22%, respectively. High salt concentration and very low wastewater temperature were possible reasons for these unexpectedly low P and TIN removal efficiencies. In contrast, removal rates of bacteria (Escherichia coli, enterococci) and organic matter (as BOD) were high, due to filtration in the alkaline medium Polonite((R)) (Ecofiltration Nordic AB, Stockholm, Sweden) and the fine sand used as SBCW substrate. High pH in effluent from the PTP was efficiently reduced to below pH 9 in the SBCW, meeting recommendations by environmental authorities in Sweden. We concluded that treating cold on-site wastewater can impair treatment performance and that technical measures are needed to improve SBCW performance.

  • 14.
    Hamisi, Rajabu
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Agnieszka
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Wörman, Anders
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Resources, Energy and Infrastructure.
    Modelling Phosphorus Sorption Kinetics and the Longevity of Reactive Filter Materials Used for On-site Wastewater Treatment2019In: Water, Vol. 11, no 4, article id 811Article in journal (Refereed)
    Abstract [en]

    Use of reactive filter media (RFM) is an emerging technology in small-scale wastewater treatment to improve phosphorus (P) removal and filter material longevity for making this technology sustainable. In this study, long-term sorption kinetics and the spatial dynamics of sorbed P distribution were simulated in replaceable P-filter bags filled with 700 L of reactive material and used in real on-site treatment systems. The input data for model calibration were obtained in laboratory trials with Filtralite P®, Polonite® and Top16. The P concentration breakthrough threshold value was set at an effluent/influent (C/C0) ratio of 1 and simulations were performed with P concentrations varying from 1 to 25 mg L−1. The simulation results showed that influent P concentration was important for the breakthrough and longevity, and that Polonite performed best, followed by Top16 and Filtralite P. A 100-day break in simulated intermittent flow allowed the materials to recover, which for Polonite involved slight retardation of P saturation. The simulated spatial distribution of P accumulated in the filter bags showed large differences between the filter materials. The modelling insights from this study can be applied in design and operation of on-site treatment systems using reactive filter materials

  • 15.
    Hamisi, Rajabu
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Agnieszka
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Wörman, Anders
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Modelling phosphorus sorption kinetics and the longevity of reactive filter materials used for on-sitewastewater treatment2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 4, article id 811Article in journal (Refereed)
    Abstract [en]

    Use of reactive filter media (RFM) is an emerging technology in small-scale wastewater treatment to improve phosphorus (P) removal and filter material longevity for making this technology sustainable. In this study, long-term sorption kinetics and the spatial dynamics of sorbed P distribution were simulated in replaceable P-filter bags filled with 700 L of reactive material and used in real on-site treatment systems. The input data for model calibration were obtained in laboratory trials with Filtralite P®, Polonite® and Top16. The P concentration breakthrough threshold value was set at an effluent/influent (C/C 0 ) ratio of 1 and simulations were performed with P concentrations varying from 1 to 25 mg L -1 . The simulation results showed that influent P concentration was important for the breakthrough and longevity, and that Polonite performed best, followed by Top16 and Filtralite P. A 100-day break in simulated intermittent flow allowed the materials to recover, which for Polonite involved slight retardation of P saturation. The simulated spatial distribution of P accumulated in the filter bags showed large differences between the filter materials. The modelling insights from this study can be applied in design and operation of on-site treatment systems using reactive filter materials.

  • 16.
    Hamisi, Rajabu
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Agnieszka
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Wörman, Anders
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Resources, Energy and Infrastructure.
    Phosphorus sorption and leaching in sand filters used for onsite wastewater treatment - a column experimentIn: Article, book review (Refereed)
    Abstract [en]

    The sorption capacities of filter sands used for onsite wastewater treatment and their associated risks of phosphorus (P) leakage on contact with rainwater were investigated in column experiments and modelling studies. Columns packed with sand were exposed to real domestic wastewater of different characteristics and hydraulic loading modes. The wastewater fed into the columns was effluent collected from three different treatment units in the field: a septic tank (ST), biofiltration tank (BF) and Polonite® filter bag (PO). The risk of P leaching to groundwater and surface water was also assessed, by exposing the same sand columns to artificial rainwater. The results indicated that sand columns can exhibit different adsorption capacities for Total-P, phosphate-P and total suspended solids, depending on the characteristics of influent wastewater. The adsorption capacity increased in the order ST > BF > PO, based on availability of organic matter to form biofilm. Effluent from Pol columns was significantly clearer, indicating lower organics content, than effluent from ST and BF columns. The modelled breakthrough curves for Total-P desorption agreed satisfactorily with the measured values, but further model improvement is needed.

  • 17.
    Hamisi, Rajabu
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Agnieszka
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Wörman, Anders
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Resources, Energy and Infrastructure.
    Simulating the hydraulic dynamics and treatment performance of a sequencing batch flow constructed wetlandIn: Article, book review (Refereed)
    Abstract [en]

    In a six-month field trial, the performance of a full-scale sequencing batch flow constructed wetland (SBCW) treating on-site wastewater was determined. The filling and draining periods lasted 5-9 days, depending on wastewater production by users (two households). The results indicated that the SBCW system efficiently removed ammonium-nitrogen (NH4-N, 76%) and Escherichia coli (89%). However, draining by pumping increased preferential water flow and considerably limited removal of dissolved phosphorus (PO4-P) in the filter bed. Analysis of water samples from nine points and three vertical levels of the wetland bed showed that pumping aerated the bed, resulting in removal of NH4-N being highest in the top 0-0.2 m layer (43%) intermediate in the 0.2-0.4 m layer (32%), and lowest in the deep (0.4-0.6 m) layer (4%). Complementary modeling using COMSOL Multiphysics software to predict the hydraulic dynamics for three different SBCW designs indicated that the drainage system of the present SBCW should be re-designed to increase contact time and aeration, for improved phosphorus and nitrogen removal.

  • 18.
    Hasselström, Linus
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. Anthesis Enveco AB, Sverige.
    Håkansson, Cecilia
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Noring, Maria
    Kemikalieinspektionen.
    Soutukorva, Åsa
    Enveco.
    Khaleevac, Julia
    Costs and benefits associated with marine oil spill prevention in northern Norway2017In: The Polar Journal, ISSN 2154-896X, E-ISSN 2154-8978, Vol. 7, no 1, p. 165-180Article in journal (Refereed)
    Abstract [en]

    The purpose of this study is to analyse conflicts regarding natural resources and ecosystem services involving different stakeholder groups using cost–benefit analysis (CBA). The paper is formed around a specific case study in Lofoten–Vesterålen in northern Norway, investigating costs and benefits of decreasing the probability of a major oil spill from shipping in the area. Benefits of decreasing the probability of a spill are far greater than costs, which means that measures to improve maritime safety would be economically profitable for society. Figures showing the effects of the impacts on fisheries and tourism sectors indicate that, compared to the total value for society, the market values of decreasing the probability of a spill are very small. On the other hand, non-market values associated with the protection of ecosystem services are of a much greater magnitude. These results suggest that the neglecting of non-market ecosystem service values in economic assessments for the Arctic may cause a biased picture of costs and benefits associated with measures to prevent environmental degradation. When feeding into decisions, such assessments may lead to too little preventive action from an economic perspective.

  • 19.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. Department of Geology and Mineralogy, Åbo Akademi, Åbo, Finland.
    Drainage in Sweden -the past and new developments2019In: Acta Agriculturae Scandinavica - Section B, ISSN 0906-4710, E-ISSN 1651-1913, Vol. 69, no 5, p. 405-410Article in journal (Refereed)
    Abstract [en]

    Land drainage in Sweden has been regulated in various laws since the Middle Ages. The lowering of lake surfaces and the ditching of wetlands has been considered a valuable task to gain cultivable land, and more recently, to promote forest growth. However, in recent years the debate surrounding drainage in forests has been a matter of considerable discussion. The dry and hot summer of 2018 has awakened new views on the subject. Monitoring has shown an exceptionally low groundwater levels countrywide. Especially the islands of Öland and Gotland have faced groundwater shortages and the groundwater levels are still low in both small and large aquifers. Drainage within forest land has lacked any scientific basis until rather recently. Still, it has been a supported activity during the twentieth century. However, this has gradually as knowledge on the activity has increased and the ecology of downstream water bodies has been considered. Today, only the rinsing of existing drainage is actively practised, and it is surrounded by a number of recommendations which are still under discussion.

  • 20.
    Jacks, Gunnar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Nystrand, M.
    Abo Akad Univ, Dept Geol, SF-20500 Turku, Finland..
    Speciation of trace elements in groundwater, surface water and sediments: a short review2019In: Environmental Earth Sciences, ISSN 1866-6280, E-ISSN 1866-6299, Vol. 78, no 12, article id 349Article, review/survey (Refereed)
    Abstract [en]

    In order to understand the interaction between groundwater, surface water and sediments, there is a need for speciation analysis of trace elements in the mentioned matrices. This could be done experimentally or by calculation with e.g. thermodynamic codes. This article will give a short overview of methods with some examples and results. Speciation in water could be determined by thermodynamic calculations with e.g. PHREEQC or Visual MINTEQ. Experimental speciation in water could be done by ultrafiltration or dialysis in situ. If applicable, in situ dialysis in the field is simple with little need of equipment. Speciation of trace elements in drinking water is of special interest to assess possible health effects. Speciation of trace elements in sediments and soils can be done by any one of the numerous selective extractions. Which speciation approach depends on which trace elements are of interest. A common need is to get information about plant uptake of specific elements.

  • 21.
    Joyce, Peter James
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Finnveden, Göran
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Håkansson, Cecilia
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Wood, Richard
    Norwegian Univ Sci & Technol, Dept Energy & Proc Engn, N-7491 Trondheim, Norway..
    A multi-impact analysis of changing ICT consumption patterns for Sweden and the EU: Indirect rebound effects and evidence of decoupling2019In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 211, p. 1154-1161Article in journal (Refereed)
    Abstract [en]

    Information and Communication Technology (ICT) is one of the major areas of growth in consumption seen over the last two decades. The falling prices of ICT and increasing energy efficiency of ICT may lead to reduced spending on ICT and electricity in the future. However, lower spending in one area can trigger higher spending elsewhere, leading to 'rebound effects' which can reduce or even cancel out the environmental benefits associated with lower consumption of a given product or service, and reducing the efficacy of environmental policy. In this study we use Multi-Regional Input Output analysis to investigate trends in the consumption of, and environmental and social impacts associated with la products in Sweden and the EU. We find that ICT spending is linked to prosperity, with a clear fall as a result of the 2008 financial crisis, but a recovery since. There is some evidence that the environmental impact associated with ICE has begun to decouple from consumption in Sweden, but not at an EU level. Environmental rebound effects associated with reduced ICT consumption are strong close to, and in most cases far above 100% (so called backfire effects). This backfire effect is strongest for energy use and total material footprint, which are both close to 200% in Sweden. This means that an increased spending on ICE products and services while keeping the overall consumption level constant, would decrease environmental impacts. Environmental rebound effects are much lower for reduced energy spending (as low as 2 percent), particularly at an EU level. Rebound effects in social indicators are assessed for the first time for 10' products. We find that value added in the EU is relatively insensitive to changes in spending patterns related to ICT and energy (rebound effects similar to 100%), however rebound effects in employment are seen, particularly resulting from decreased energy spending. At an EU level, reallocation of spending resulting from lower energy consumption results in a net increase in employment, while in Sweden the reverse is true. We conclude that policies focused on reducing energy spending are likely to have a greater overall environmental effect than measures which result in reduced consumer spending on ICT. However, in light of the conflicting social rebound effects at an EU and Swedish level, the importance of understanding the broader consequences of policy decision across a broad range of measures in advance of their implementation is once again highlighted.

  • 22.
    Kadefors, Anna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    Uppenberg, Stefan
    WSP.
    Alkan-Olsson, Johanna
    Lunds universitet, Centre for Environmental and Climate Research .
    Balian, Daniel
    WSP.
    Lingegård, Sofia
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Procurement Requirements for Carbon Reduction in Infrastructure Construction Projects: An International Case Study2019Report (Other academic)
    Abstract [en]

    Executive Summary

    Introduction

    Following alarming reports from the IPCC, climate change has engaged policymakers world-wide to chart policies at different administrative levels to mitigate increasing greenhouse gas emissions. The construction sector causes a substantial part of all greenhouse gas emissions, primarily carbon dioxide. Traditionally in this sector, the focus of carbon reduction measures has been on improving the energy efficiency of buildings. Further, various sustainability assessment schemes (BREEAM, LEED, Green Star, etc.) have been developed to assess sustainability performance. More recently, awareness has increased of the considerable greenhouse gas emissions arising from the manufacturing of construction materials and components, and also from construction processes and transport. Consequently, the infrastructure construction sector is now considered as a major source of greenhouse gases. In the UK, The Infrastructure Carbon Review has estimated that the construction, maintenance and operations of infrastructure assets account for 16% of the nation’s total carbon dioxide emissions. It is widely acknowledged that these emissions need to be significantly reduced if the international and national reduction targets are to be met.

    About the project

    This research project has investigated the institutional and organisational contexts, policies, procurement requirements and implementation strategies used to drive greenhouse gas reduction in large infrastructure projects in five countries world-wide: Australia, The Netherlands, Sweden, the UK and the US (see below for an overview of case study projects). The study is based on interviews with key partners on the client side and in the supply chain of each project. To provide a contextual understanding of the strategies used in these projects, we further include descriptions of the policy background that underlies current strategies and ambitions. Thus, the project traces the pathway from political and organisational goals to actual realisation in projects.

    Overview of case studies in the Impres project

    Country

    Impres case studies

    Australia

    Sydney Metro Northwest

    Newcastle Light Rail

    The Netherlands

    Motorway A6 Almere

    Sweden

    Results from the Swedish Transport Administration research project Control Station 2018 - an evaluation of carbon procurement requirements in Swedish infrastructure projects.

    UK

    High Speed 2

    Anglian Water (Grafham WTW Resilience and Dalton Piercy WTW) 

    USA

    California High-Speed Rail

    SFO AirTrain Extension

     

    The title of this research project is Implementation of procurement requirements for sustainable collaboration in infrastructure projects, also referred to as Impres. The project is a collaboration between the engineering consultancy firm WSP, the KTH Royal Institute of Technology in Stockholm, Lund University and the construction company Skanska. The project is co-financed by Construction Climate Challenge (CCC), a sustainability research fund and network initiated by Volvo Construction Equipment, and the Swedish Research Council Formas. The latter funding comes through a grant for the Strong Research Environment ProcSIBE, Procurement for Sustainable Innovation in the Built Environment[1].

    We expect that results from this research project will be useful for decision-makers on the client side that are in charge of developing policies, procurement strategies and procurement requirements to reduce carbon emissions in the construction sector. Further, client and contractor project managers, environmental specialists and procurement staff responsible for implementing policies will be interested in experiences gained in similar initiatives in other countries. In parallel with this report, scientific articles are being developed by the authors to analyse and discuss the results described in this report more thoroughly in relation to other studies and to theory.

    Conclusions

    In all countries studied, there is an ongoing process to develop and implement policies for carbon reduction in infrastructure projects, with raised ambitions over time. In some cases, the development has initially been driven by a few dedicated individuals, but today there are frameworks and executive mandates in place that would make it hard to avoid carbon reduction commitments. National and regional reduction policies were found to be important in encouraging clients to develop ambitious carbon requirements that can contribute to setting new industry standards.

    Carbon reduction measures such as optimisation of constructions, minimised transport, reuse of excavated material and cement clinker replacement are applied in the studied cases. However, most of these measures are also cost efficient and would – or should – have been undertaken in a normal design and construction optimisation process. The positive side of this is that considerable carbon reductions may be achieved within existing budgets, and in most cases will even reduce cost, and that an increased focus on carbon may contribute to finding more such options. However, it also raises the question of what constitutes a relevant reference case, or baseline. Further, to meet the target levels of the Paris agreement, costly measures will also be needed, and this research identified only a few examples of such policies being implemented. 

    Goals for carbon reduction are still new to many in the sector, and both clients and industry partners need time to adjust and develop new competencies. In countries with a longer history of carbon management, procurement strategies and requirements have advanced through continuous interaction between clients and industry actors over longer periods of time. Clients are wary of introducing requirements that may limit competition, and requirements to comply with rating schemes or to supply EPDs have been introduced successively to match the development of industry capacity. Award (MEAT) criteria related to carbon are used, but more often to increase awareness of carbon reduction rather than as a substantive basis for selection. Front-runner contractors and material suppliers were found to play important roles in reducing obstacles to innovation-oriented procurement. Moreover, the development of procurement requirements has been aligned with information and training initiatives, tool kits and guidelines to support low-carbon design and the calculation of emissions. In general, client environmental specialists have taken an active part in supporting the implementation of requirements in supply chains.

    Procurement requirements are considered important in driving carbon reductions in all countries, but the preferred style of these requirements vary. This diversity was partly related to general carbon management maturity and partly to general contracting practice and policy culture in the country or region. All countries used some form of contract-level reduction requirements, in most cases set in relation to a carbon emissions baseline. Overall, reduction requirements are perceived to encourage innovation, but our results show that such requirements were often more complex than foreseen and associated with administrative costs. First, to produce change and avoid speculation it is important to set requirements and incentives at the right level, which requires awareness on the client side of both the supplier’s competence and of the opportunities for carbon reduction in the specific project. Also, sharp requirements call for equally sharp and transparent performance evaluation. Moreover, much time was spent on calculation and re-calculation of baselines which could detract from measures for actual reduction of carbon emissions. In effect, time constraints in the projects limited the opportunities to involve subcontractors and material suppliers, which meant that all possible reductions were not realised. We conclude that expectations for substantial and innovative carbon reductions through functional reduction requirements may be too high. To influence sub-contractors and suppliers directly, several clients use specific requirements.

    Collaborative contracting models are a flexible option to encourage innovation and integrate knowledge of different participants. Many interviewees state the importance of breaking silo-thinking and integrating the supply chain in order to reach greater carbon reductions. Also, long-term alliances allow for continuous learning and more transformational innovation, including incentivising contractors to find ways of fulfilling client goals while building less. However, it should be emphasised that strong client leadership and commitment are essential both to legitimise collaborative contracting models and to achieve more fundamental behavioural change within collaborative projects and alliance schemes.

    Clients in mega-projects perceive an obligation to conform to national policy goals and may also have ambitions to be industry-level change agents. Since such projects have vast budgets, last for long periods of time and engage highly competent firms and individuals, they are often expected to show high performance in the area of innovation. However, mega-projects have many goals to fulfil, are technically and organisationally complex and associated with high risks. Therefore, time and willingness to develop new ways of working or implement new technology may be lacking. Further, even large projects may not be long enough to encompass processes to develop, test and approve new solutions. Thus, to support more efficient innovation processes in the industry, a long-term system perspective is needed. Interviewees suggested using smaller pilot projects for quicker testing of new materials, tools and technologies and, once proven, use procurement requirements in large projects to implement these more widely in the market.

    Overall, the study shows that the applicability of procurement requirements for carbon reduction is dependent on how well these requirements are aligned with culture, policies and capabilities in the local context. Inspiration may be sought from cutting-edge examples in other countries and regions, but practices may seldom be directly transferred. Also, it is clear that awareness, competence and capacity on the buyer (client) side is a key success factor. Such client capabilities involve constructive collaboration between procurement functions, environmental specialists and project managers. Further, policy makers need to acknowledge that measures to reduce carbon must align with existing procurement and innovation systems. To reach higher levels of ambition for carbon reduction, such institutional structures may also need to be changed.

    Recommendations

    Based on the findings, our recommendations to the target group of policy-makers and clients are:

    Policy level – national, regional and organisational

    • ·         Set high-level goals and policies for carbon reduction in order to sanction ambitious initiatives that contribute to setting new industry standards.
    • ·         To reduce barriers for innovation-oriented procurement requirements, engage industry associations and encourage initiatives by supply-side front-runners.
    • ·         When developing organisational policies and strategies, address not only ambitions but also what roles the client and other parties should have in implementation.

     

    Project level policies and procurement requirements

    • ·         When defining requirements, consider implementation costs for setting and following up requirements. In particular, be careful that focus stays on carbon mitigation measures and that calculation of baselines does not impact negatively on carbon management. Assess and mitigate behavioural risks associated with incentives.
    • ·         Ensure that requirements will be effective in influencing all relevant decision-makers in the supply chain (designing engineers, constructors and material suppliers). This implies that time, competence and resources should be available at relevant points in time.
    • ·        Apply a long-term learning perspective and acknowledge that different combinations of award and selection criteria, reduction requirements, specific requirements and rating schemes may be preferable over time.
      • ·         Align requirements and activities with general contracting models and encourage models that enable integration of knowledge and carbon management in the supply chain.

     

    Innovation and learning

    • ·         Develop guidelines, tools and training programs to help build industry capabilities.
    • ·         Establish which organisations should drive development, for example commission, host and update guidelines, and provide training and support.
    • ·         Communicate plans for raised ambitions well in advance, for example requirements to comply with established carbon management standards and rating schemes.
    • ·         Orchestrate long-term innovation by combining small pilot projects to test new solutions with systematic implementation in larger projects to achieve wide market dissemination. 
    • ·         Establish transparent procedures for updating client standard specifications based on frontrunner initiatives, planned pilots and academic research.
    • ·         Innovation should also address contracting and business models: develop institutional capabilities that enable and legitimise long-term, strategic collaborative alliances.

     

    [1]www.procsibe.se

  • 23.
    Karlsson, Caroline
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Kalantari, Zahra
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Lyon, Steve W.
    Natural hazard susceptibility assessment for road planning using spatial multi-criteria analysis2017In: Environmental Management, ISSN 0364-152X, E-ISSN 1432-1009, Vol. 60, no 5, p. 823-851Article in journal (Refereed)
    Abstract [en]

    Inadequate infrastructural networks can be detrimental to society if transport between locations becomes hindered or delayed, especially due to natural hazards which are difficult to control. Thus determining natural hazard susceptible areas and incorporating them in the initial planning process, may reduce infrastructural damages in the long run. The objective of this study was to evaluate the usefulness of expert judgements for assessing natural hazard susceptibility through a spatial multi-criteria analysis (SMCA) approach using hydrological, geological and land use factors. To utilize SMCA for decision support, an analytic hierarchy process (AHP) was adopted where expert judgements were evaluated individually and in an aggregated manner. The estimates of susceptible areas were then compared with the methods weighted linear combination (WLC) using equal weights and factor interaction method (FIM). Results showed that inundation received the highest susceptibility. Using expert judgement showed to perform almost the same as Equal weighting where the difference in susceptibility between the two for inundation was around 4%. The results also showed that downscaling could negatively affect the susceptibility assessment and be highly misleading. Susceptibility assessment through SMCA is useful for decision support in early road planning despite its limitation to the selection and use of decision rules and criteria. A natural hazard SMCA could be used to indicate areas where more investigations need to be undertaken from a natural hazard point of view, and to identify areas thought to have higher susceptibility along existing roads where mitigation measures could be targeted after in-situ investigations.

  • 24.
    Karrbom Gustavsson, Tina
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    Kadefors, Anna
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Building and Real Estate Economics.
    Lingegård, Sofia
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Laedre, Ola
    NTNU,Department of Civil and Transport Engineering.
    Klakegg, Ole Jonny
    NTNU, Department of Civil and Transport Engineering.
    Olsson, Nils
    NTNU, Production and Quality Engineering.
    Larsson, Johan
    Luleå University of Technology, Civil, Environmental and Natural Resources Engineering.
    Procurement Research: Current State and Future Challenges in the Nordic Countries2019In: 10th Nordic Conference on Construction Economics and Organization (Emerald Reach Proceedings Series, Volume 2) / [ed] Irene Lill, Emlyn Witt, Emerald Group Publishing Limited, 2019, Vol. 2, p. 195-204Conference paper (Refereed)
    Abstract [en]

    Purpose

    The purpose of the study is to map previous and current construction procurement research to further develop the research in the Nordic counties.

    Design/Methodology/Approach

    Mapping of previous and current research based on search in national database. The analysis is based on research perspectives, empirical contexts and research methods.

    Findings

    That the blind spots are partly overlapping, but that there is potential for knowledge transfer in some areas. There is also the potential for a Nordic research program on one or several of the blind spots.

    Research Limitations/Implications

    The study is limited to PhD and licentiate-thesis reports in Norway and Sweden. Further research should include the other Nordic countries and a more extensive literature review including journal articles to broaden the scope. Findings have implications on collaborative Nordic research initiatives, knowledge transfer and in a longer perspective on the level of procurement knowledge in industry and society.

    Practical Implications

    Findings provide a base for future research collaborations, initiatives and applications.

    Originality/Value

    Findings provide a comprehensive understanding of construction procurement research in the Nordic countries, starting with Norway and Sweden. This understanding is needed for developing research collaborations and applications.

  • 25. Kasiuliene, Alfreda
    et al.
    Carabante, Ivan
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Caporale, Antonio Giandonato
    Adamo, Paola
    Kumpiene, Jurate
    Removal of metal(oid)s from contaminated water using iron-coated peat sorbent2018In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 198, p. 290-296Article in journal (Refereed)
    Abstract [en]

    This study aimed at combining iron and peat to produce a sorbent suitable for a simultaneous removal of cations and anions from a solution. Peat powder, an industrial residue, was coated with iron by immersing peat into iron salt solutions. The adsorption efficiency of the newly produced sorbent towards As, Cr, Cu and Zn was tested by means of batch adsorption experiments at a constant pH value of 5. Coating of Fe on peat significantly increased the adsorption of As (from <5% to 80%) and Cr (from <3% to 25%) in comparison to uncoated peat. Removal of cations on coated peat slightly decreased (by 10-15%), yet remained within acceptable range. Electron Microscopy combined with X-Ray Energy Dispersive Spectroscopy revealed that iron coating on the peat was rather homogenous and As and Cr were abundantly adsorbed on the surface. By contrast, Cu and Zn displayed a sparing distribution on the surface of the iron coated peat. These results indicate that iron-peat simultaneously target sufficient amounts of both cations and anions and can be used for a one-step treatment of contaminated groundwater.

  • 26.
    Kholoma, Ezekiel
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Agnieszka
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Filter media-packed bed reactor fortification with biochar to enhance wastewater treatmentManuscript (preprint) (Other academic)
    Abstract [en]

    Contamination of water bodies with inappropriately released, poorly treated wastewater from rural establishments is a challenge world-wide. Rural communities in developed countries are now required to comply with statutory discharge limits, but less costly alternative technologies by which to comply are scarce. However, it is possible that retrofitting on-site facilities with specialist treatment units could provide a feasible solution. This study tested the effectiveness of retrofitting sand (Sa)- and gas-concrete (GC)-packed down-flow reactors with biochar (BC) in removing turbidity, dissolved organic carbon (DOC), phosphate (PO43-) and total phosphorus (TP) from wastewater. The reactors were each intermittently loaded with 0.063 L/d for 399 days. In general, all reactors achieved <3 NTU effluent turbidity (99% efficiency). The GC reactors were best at removing incoming PO43- (6.1 mg/L) and DOC (25.3 mg/L), trapping >95% and >60%, respectively. Compared with a reference Sa reactor (PO43- removal 35%; DOC removal 52%), the fortified sand (Sa-BC) filter removed significantly more PO43- (>45% removal, p=0.022) and DOC (>58% removal, p=0.034). In regression analysis, 53%, 81% and 85% of PO43- sorption variation in Sa, BC and Sa-BC filters, respectively, was explained by variations in reactor effluent pH. Similarly, a strong linear correlation was found between PO43- sorption efficiency and the pH of fortified (GC-BC, r > 0.7) and reference (r = 0.6) GC filters, suggesting chemisorption mechanisms. Therefore, if only sand is readily available for treating septic tank effluent, fortifying it with biochar could be a possible measure to improve its efficacy.

  • 27.
    Kholoma, Ezekiel
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    A review of the potential of reactive filter media in fortifying on-site wastewater treatment systems - Lessons from full-scale wastewater treatment systems ManuscriptManuscript (preprint) (Other academic)
    Abstract [en]

    Wastewater with high concentrations of nutrients, pathogens and many micro-pollutants is usually satisfactorily treated by application of technologies which employ chemical processes. However, due to the absence of these processes in most small-scale wastewater treatment (SWT) systems, pollutants often escape treatment and ultimately end up in water bodies, hence the persistence of eutrophication and waterborne diseases experienced in many parts of world. Due to the recent introduction of requirements for SWT systems to comply with national discharge standards, alternative effective technologies are needed. Among the wide spectrum of supposedly effective alternative technologies which have been developed to-date, some can be incorporated to extend treatment chains of ineffective SWT facilities, e.g. package treatment plants and wetlands, while others are designed to enhance processes in some treatment steps, e.g. bioreactors for pre-treatment. However, due to the high costs, complexity and scarcity of many of these advanced technologies, reactive filter (RF) media are seemingly preferred. Much current knowledge about the potential of RF media is based on batch and column experimental findings. Therefore, various aspects of RF media relating to performance in full-scale plants are generally unknown. To our knowledge, no previous study has outlined the importance of key parameters distinguishing the performance of different RF media in full-scale plants or suggested the use of versatile media. This study therefore acquired and compiled data on RF media previously tested in full-scale plants, to compare and highlight parameters relating to their potential in treating wastewater of different strengths.

  • 28.
    Kholoma, Ezekiel
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Zhang, Wen
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Agnieszka
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Leachability and plant availability of phosphorus in post-sorption wastewater filters fortified with biocharManuscript (preprint) (Other academic)
    Abstract [en]

    Sand and gravel are widely applied in field filter systems for small-scale wastewater treatment. However, alternative filter materials are needed to achieve better treatment performance in removing contaminants and trapping plant nutrients for recycling to agriculture. This study assessed the plant availability and leachability of phosphorus (P) trapped in sand (Sa), biochar (BC) and gas concrete (GC, Sorbulite®) media used previously for phosphorus (P) removal in laboratory-scale packed bed reactors (PBR) and field-scale constructed filter beds (CFB). Phosphorus extraction and leaching were assessed in batch and leaching experiments using distilled water and ammonium lactate (AL) solution with a 1:20 solid:extractant ratio. The results revealed that both Sa (11.2 mgkg-1) and BC-fortified Sa (20.5 mgkg-1) leached P to percolating water, while P was less likely to leach from GC systems. Extraction with AL showed that the P retained in GC was plant-available and that the GC materials could release 65-90 mgkg-1 of the bound P mass. These findings highlight the need to evaluate the risk of nutrient leaching from filter media used in small-scale wastewater treatment systems with groundwater and surface water as final recipients. For greater sustainability, the P weakly bound in media such as sand and biochar and strongly bound in media such as gas concrete should be recovered by recycling the spent material to agriculture. However, this would require treatment system re-design to make recycling of filter material technically possible.

  • 29.
    Kianmeher, Peiman
    et al.
    Amer Univ Dubai, Dept Civil Engn, Dubai, U Arab Emirates..
    Alazawi, Sundus
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Enhancement of Physicochemical Properties of Dubai's Sand to Conserve Irrigation Water2018In: PROCEEDINGS OF 3RD INTERNATIONAL SUSTAINABLE BUILDINGS SYMPOSIUM (ISBS 2017), VOL 1 / [ed] Firat, S Kinuthia, J AbuTair, A, SPRINGER INTERNATIONAL PUBLISHING AG , 2018, p. 644-654Conference paper (Refereed)
    Abstract [en]

    Freshwater scarcity has been a considerable issue in the Gulf Region. The cities in the region including in the UAE depend mainly on seawater desalination. Their demand escalated about 15% annually regardless of seawater desalination direct cost of 1 US$/M-3. Thus, calling all water conservation techniques to reducing indoor and outdoor water demands is inevitable. Using Hydrophobic Sand (HS) to reduce water seepage and increase the contact time between irrigation water and plants' roots was seen as potential conservation technique. The HS is Normal Sand (NS) coated by a thin layer of hydrophobic organic silica compound called trimethylsilanol. However, concerns were raised about the leaching of harmful organic coating chemicals into the soil and groundwater. Assessing the potential risks of leaching additives is one of the objectives of this research. For some plants, requiring a certain range of soil permeability suggests a mixture of NS and HS. The permeability of mixtures of HS with abundant NS was examined to assess its validity and cost effectiveness when a certain permeability is required. Several elements leaching tests were conducted. The soil was classified and constant head permeability test was conducted for different configurations and mixtures of NS and HS. The leached elements, nutrients and organic silica were within the allowable limits set by the typical standards. Further experiments indicates that HS does not constitute an environmental hazard. Mixing different portions of NS and HS revealed unforeseen increase in the permeability. Instead, some layer configurations could reduce soil permeability.

  • 30. Maity, J. P.
    et al.
    Chen, C. -Y
    Bundschuh, J.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Mukherjee, A.
    Chang, Y. -F
    Hydrogeochemical reconnaissance of arsenic cycling and possible environmental risk in hydrothermal systems of Taiwan2017In: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 5, p. 1-13Article in journal (Refereed)
    Abstract [en]

    Hydrothermal activity creates geo-hydro-chemical interactions between hot water/fluid and the host rocks, which changes the hydro-chemical composition of the geothermal water/fluid and enriches trace elements. Existence of arsenic (As) is reported from different hydrothermal systems as well as several region in groundwater system at elevated concentration globally, compared to 10 μg/L WHO (World health Organization) guideline. The distribution of dissolved major and minor elements, including arsenic (As) was studied in hydrothermal systems of Taiwan. For the first time in Taiwan As(V) and As(III) species were researched from the three principal geological settings of Taiwan. Aim was to understand the cycling, fate and transport and potential impact of As on the surficial hydrological systems. Water samples were collected from sixteen hydrothermal springs of 3 different geological settings. Three groups of hydrothermal spring water samples could be distinguished: (i) strongly acidic (pH&lt;3), sulfate-enriched waters of H-SO4-type (Yangmingshan, and Taipu, Beitou), (ii) slightly alkaline waters (pH: 8–8.95) (Jiben, Antung and Kung-Tzu-Ling), and (iii) circum-neutral waters (pH 6.47–7.41) of Na-HCO3/Na-Cl-HCO3-type (Wulai, Hongye, Rueisuei, Chung-Lun and Biolai). The waters are enriched with alkali and alkali earth metals compared to drinking water. Similarly, the water of most of the geothermal springs were found to be enriched with As (highest concentration at Beitou: 1.456 mg/L) with As(III) being the principal As species. Arsenic concentrations of hydrothermal spring waters in igneous rock terrains exhibit highest concentrations (0.69±0.71 mg/L) followed by those of sedimentary (0.16±0.14 mg/L) and metamorphic (0.06±0.02 mg/L) terrains. The discharged geothermal springs water contaminate the surface and groundwater (including drinking and irrigation water resources), where significant levels of arsenic and other toxic element have detected and hence being a significant risk for human health and environmental.

  • 31. Maity, J. P.
    et al.
    Hsu, C. -M
    Lin, T. -J
    Lee, W. -C
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Bundschuh, Jochen
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. University of Southern Queensland, Australia.
    Chen, C. -Y
    Removal of fluoride from water through bacterial-surfactin mediated novel hydroxyapatite nanoparticle and its efficiency assessment: Adsorption isotherm, adsorption kinetic and adsorption Thermodynamics2018In: Environmental Nanotechnology, Monitoring and Management, ISSN 2215-1532, Vol. 9, p. 18-28Article in journal (Refereed)
    Abstract [en]

    Fluoride contamination in water due to natural and anthropogenic activities has been documented as serious problems worldwide commanding a major threat to the environment. Present study focuses to synthesis bacterial-surfactin (Bacillus subtilis) mediated nano-hydroxyapatite (HAp), novel adsorbents for defluoridation. HAp particle size and morphology were controlled by varying temperature of 90–150 °C and pH of 7–11, respectively. The TEM and SEM micrographs reveal that the short-rod particle is observed 20–30 nm at 90 °C and pH 11. The ratio between the length (nm) and width (nm) of nanoparticle are decreased from 4.17 to 1.65 with increasing pH (7–11). The selected area diffraction (SAD) of particles are indicated uniform rod-like monocrystals. The XRD and FTIR observations were indicated the synthesized HAp nanoparticles were well-crystallized with purity phase and high quality. The study reflected that the fluoride removal from contaminated water by HAp was increased significantly (R2 = 99) with the increasing adsorbent concentration, temperature and time, with two-step adsorption process as the first portion a rapid adsorption occurs during first 90 min after which equilibrium is slowly achieved. The adsorption process is closer to Freundlich isotherm (R2 &gt; 98) than to Langmuir isotherm (R2 ≈ 92), indicating HAp as a good adsorbent (n &gt; 3). Above 97% of fluoride removal were noticed at a HAp dose of 0.06 g/10 mL. The adsorption kinetics more fit with pseudo-second-order (R2= 99) in compare to pseudo-first-order (R2 ≈ 91). The slope and intercept of Arrhenius equation indicated the activation/adsorption energy (Ea) of 3.199 kJ/mol and frequency factor (A) of 1.78 1/s. Adsorption thermodynamic parameters (free energy (ΔG &lt; 0), enthalpy (ΔH &gt; 0) and entropy (ΔS &gt; 0)) indicates the spontaneous and endothermic reactions of the adsorption process. Thus, newly synthesized HAp nanoparticles exhibit as a good adsorbent for fluoride removal, theoretically and experimentally being applicable for environmental pollution control.

  • 32. Melander, L.
    et al.
    Lingegård, Sofia
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Is the pace of technology development a threat or opportunity for sustainability?: the case of remanufactured industrial robots2018In: Procedia CIRP, Elsevier B.V. , 2018, p. 247-252Conference paper (Refereed)
    Abstract [en]

    Remanufacturing has been identified as having much potential and providing a wide range of benefits. However, challenges remain for remanufacturing to be widely accepted, both from customers as well as within industrial firms. Business models for remanufacturing are complex and remanufacturing requires multiple competences across the firm. This paper is a study of the remanufacturing market for industrial products and is exemplified by a case study of a leading robot company in the US market. The study shows that rapid technology development impacts the remanufacturing possibilities and as such has an impact on sustainability. Technology development can be seen as a threat to remanufacturing e.g. making products become obsolete as well as leading to compatibility problems where it is difficult to find spare parts. Technology development also results in cheaper robots, making it difficult to provide economic incentives to buy remanufactured products. However, fast technology development can also be a possibility to firms that have well developed remanufacturing processes, as they are able to adjust to newer technologies. The study also points to the importance of cross-functional collaboration in the design phase of products, where remanufacturing needs to be considered. The article provides implications on how to manage rapid technology development in remanufacturing. 

  • 33.
    Niarchos, Georgios
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Electrodialytic Remediation of PFAS-Contaminated Soil2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Per- and polyfluoroalkyl substances (PFASs) are a group of anthropogenic aliphatic compounds, widelyknown for their environmental persistence and toxicity to living beings. While they are ubiquitous in theenvironment, interest has been focused on contaminated soil, which can act as a primary recipient andsource of groundwater contamination. Electrokinetic technology is based on the movement of ionsunder the effect of an electric field. This could be a promising remediation solution, since PFASs areusually present in their anionic form. The contaminants can then be concentrated towards the anode,thus reducing a plume’s volume and possibly extracting the substances from soil. The preliminary aimof the present study was to evaluate the potential of using electrodialysis for the remediation of PFAScontaminatedsoil for the first time. Experiments were run with natural contaminated soil samples,originating from a fire-fighting training site at Arlanda Airport, and at Kallinge, Sweden, as well as inartificially spikedsoil. Electrodes were placed in electrolyte-filled chambers and separated by the soilwith ion-exchange membranes for pH-control. In total, five experiments were conducted. Two differentsetups were tested, a typical 3-compartment EKR cell and a 2-compartment setup, to allow for pHincrease and facilitate PFAS desorption. Two different current densities were tested; 0.19 mA cm-2 and0.38 mA cm-2. After twenty-one days, soil was cut in ten parts lengthwise and triplicate samples wereanalysed for PFAS concentrations, with HPLC-MS/MS. Sixteen out of the twenty-six screened PFASswere detected above MDL in the natural soil samples. The majority of the detected PFASs showed apositive trend of electromigration towards the anode, under both current densities, with only longerchainedcompounds (c>8) being immobile. This can be attributed to the stronger sorption potential oflong-chained PFAS molecules, as has been reported in previous sorption studies. Mass balancedistribution for a high current density (0.38 mA cm-2) experiment revealed that 73.2% of Σ26PFAS wasconcentrated towards the anode, with 59% at the soil closer to the anode, 5.7% at the anion exchangemembrane and 8.5% at the anolyte. It also showed higher mobility for short-chained molecules (c≤6),as they were the only compounds to be extracted from soil and be concentrated in the anolyte. Highercurrent densities were not directly correlated with higher electromigration rates, as to the lack of massbalance data for the low current density experiments. Regardless, electrodialysis could be a viable optionfor PFAS soil remediation and further research to encourage the understanding of the migrationmechanism, as well as combination with other treatment methods is encouraged.

  • 34.
    Paul, Seema
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Data preparation, hydrodynamic and contaminant transport shallow-water simulations of Lake Victoria2019Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This study explores shallow lake numerical hydrodynamic processes that support model development and validation, extreme events and effects of water circulation in Lake Victoria. Lake Victoria is the second largest freshwater lake in the world, and the largest in East Africa. It is the major freshwater reservoir and source for domestic, agriculture, industrial, fishery, and transport. The resources support livelihoods and ecosystem services for over 40 million people. The lake is severely affected by water quality degradation by pollution. This thesis aims at improving the understanding by following recommendation of the Lake Victoria Environment Management Project, Lake Victoria Basin Commission climate change adaptation strategy and action plan 2018-2023, Lake Victoria Basin Commission operational plan 2015-2020, and Lake Victoria Basin Commission report. These reports suggested detailed lake bathymetry survey, modelling of lake flow, study of lake hydrometeorological processes by modelling and simulation, to identify extreme weather events, assess water circulation effect, and study lake pollution near the shore. A numerical hydrodynamic model was built in the COMSOL Multiphysics (CM) software for assessing lake flows and water turn-over from river inflows which carry pollution. The work included the development of systematic methods for lake bathymetry that are relevant for lake numerical and hydrodynamic modelling. The hydrometeorological driven simulation model was employed to assess lake water balance, water circulation and soluble transport. Paper 1 creates a bathymetry from several methods and from several data sources, and a vertically integrated free surface flow model was implemented in CM. The model was used to investigate outflow conditions, mean velocities driven by river inflow, outflow, precipitation and evaporation. It is shown to be exactly conservative and give water level variation in reasonable agreement with measurements. The results indicate that the shallow water model is close to linear. An outflow model, linear in water level, predicts water level reasonable agreement with measurements. The findings suggest that the model should consider wind stress driven flow to provide more accurate lake flow behavior. Paper 2 performed an assessment of the hydro-meteorological processes and extreme weather events that are responsible for changing the characteristics of lake water balance, and changing streamflow variations, and lake transportation. We compare historical data over a long time with data from the model including water balance, sources of data uncertainty, correlations, extreme rain and inflow years, and seasonal variations. Solute loading and transportation was illustrated by tracing the water from the river inflows. The results indicate that the lake rainfall has a strong seasonal variation with strong correlations between tributary inflows and precipitation, and between lake outflow and water level. The tracer transport by mean flow is very slow. Flow increases somewhat in wet periods and is faster in the shallow Kenya lake zone than in the deeper Uganda and Tanzanian lake zones, where the major inflow, from the Kagera River, appears to strongly influence transportation.

  • 35.
    Paul, Seema
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Oppelstrup, Jesper
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Numerical Analysis, NA.
    Hydro-meteorological processes driving solute transport in Lake VictoriaManuscript (preprint) (Other academic)
    Abstract [en]

    This study explores by a vertically integrated tracer transport model, hydro-meteorological event characteristics and their influence on solute transport. Changes in Hydro-meteorological processes and increasing frequency of extreme weather events are responsible for changing the lake water balance, influencing streamflow variations, and lake tracer transport. We compare historical data over a long time with model data from a vertically integrated model in Comsol Multiphysics. We consider water balance, sources of data uncertainty, correlations, extreme rain and inflow years, and seasonal variations. The lake transport model has estimated soluble loading and transportation. The results showed that the lake rainfall is seasonal; there are strong correlations between tributary inflows and precipitation, and between lake outflow and water level. It was found that “events” influence lake level fluctuations. The solute transport was shown to vary more in wet periods. Modeled transportations were higher in Kenya and Uganda lake zones than in Tanzanian zones. The major inflow, from the Kagera river, appears to strongly influence lake solute transportation, so the composition of this river must be considered.

  • 36.
    Paul, Seema
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Oppelstrup, Jesper
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Numerical Analysis, NA.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Mango Magero, John
    Makerere University.
    DDumba Walakira, David
    Makerere University.
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Bathymetry Development and Flow Analyses Using Two-Dimensional Numerical Modeling Approach for Lake Victoria2019In: Fluids, ISSN 2311-5521, Vol. 4, no 4, p. 1-21Article in journal (Refereed)
    Abstract [en]

    This study explored two-dimensional (2D) numerical hydrodynamic model simulations of Lake Victoria. Several methods were developed in Matlab to build the lake topography. Old depth soundings taken in smaller parts of the lake were combined with more recent extensive data to produce a smooth topographical model. The lake free surface numerical model in the COMSOL Multiphysics (CM) software was implemented using bathymetry and vertically integrated 2D shallow water equations. Validated by measurements of mean lake water level, the model predicted very low mean flow speeds and was thus close to being linear and time invariant, allowing long-time simulations with low-pass filtered inflow data. An outflow boundary condition allowed an accurate simulation to achieve the lake’s steady state level. The numerical accuracy of the linear measurement of lake water level was excellent.

  • 37.
    Rasul, Hedi
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. Koya University.
    Water in roads: Flow paths and pollutant spread2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    For better road construction and maintenance while minimising damage to the environment and groundwater, it is essential to monitor and model hydrological impacts on roads and consider pollution of groundwater. Water content in unbound material in road layers changes continuously and water flow usually occurs along pathways that are the main corridors for pollutant spread to groundwater. Good awareness of hydrological conditions and of water and solute transport in road layers down to the groundwater can be helpful in minimising environmental impacts during construction and operation. Today, road planning is usually carried out without specifically considering hydrological criteria. To improve understanding of the links between water in roads and groundwater, this thesis developed investigation methods and used numerical simulations for estimating seasonal variations, flow pathways and pollutant spread.

    Seasonal changes in road water content in an operational road, tracer tests pathways from the road shoulder and percolation down to groundwater were monitored non-destructively using electrical resistivity tomography (ERT). Chloride concentration changes were estimated based on ERT data inversion. New monitoring methodology was assessed and data analysis was performed on ERT data from different road zones and layers, which were analysed statistically and correlated to precipitation, temperature and ground moisture content. Data were collected at a unique road test station on a motorway north-west of Stockholm and in tracer experiments on typical roads in southern and central Sweden. Two-dimensional (2D) models of heat and moisture changes were prepared for a road section, considering vapour pressure and frozen water content changes using partial differential equations (PDE). Model parameters were optimised based on soil moisture and temperature data from the E18 road test station. A PDE model was used for calculating liquid water and ice content changes in different scenarios based on geometry and design changes. Both pathways and travel times were traced by 2D and pseudo 3D inverse modelling of the ERT measurements.

    The field data revealed clear preferential pathways of moisture and salt in the road shoulders that varied significantly during different seasons. Most infiltration occurred directly into the road shoulder, but entered the road embankment with higher percolation speed in modern roads than in old roads consisting of natural soils. The simulations showed that seasonal climate changes and the upper boundary condition were key factors determining water content in different road layers. These findings advance understanding of water in roads and represent a step towards more sustainable and environmental friendly road construction and maintenance. In addition the research results give lessons for practice both regarding monitoring and road construction. For monitoring it provides a new method in data collection and analysis. For construction and maintenance, mitigation measures are suggested, which comprise a tight road shoulder, by e.g. adding a fine grained layer on the shoulder or covering with vegetation.

  • 38.
    Rasul, Hedi
    et al.
    Koya University.
    Earon, Robert
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Detecting seasonal flow pathways in road structures using tracer tests and ERTIn: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932Article in journal (Other academic)
    Abstract [en]

    Roads and traffic can be a source of water-bound pollutants, which can percolate through the unsaturated zone to groundwater. Deicing salt is widely used on roads in northern Europe during winter and is usually applied at a time when the temperature is below zero and the soil is partly frozen. Understanding the mechanism by which water-bound pollutants such as deicing salt are transferred from roads to groundwater is highly important for groundwater protection, environmental sustainability and road maintenance. Electrical resistivity tomography (ERT) can be used for tracing the infiltration of deicing salt in different seasons, including the frozen period, as a step towards identifying pollutant infiltration pathways. In this study, a tracer-ERT monitoring method and analytical process was developed and evaluated for use in investigating and demonstrating deicing salt infiltration pathways in road structures in different seasons and weather conditions. The method involves using dissolved sodium chloride as a tracer and monitoring its infiltration using a multi-electrode array system. The tracer tests were performed at the same location in different seasons over a one-year period.

    The results indicated high seasonal variation in percolation pattern and flow velocity, with large decreases in December (winter), most likely due to preferential flow paths within the road shoulder. These findings can be applied to other water-soluble pollutants that move from the road surface to groundwater.

  • 39.
    Rasul, Hedi
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. Royal Inst Technol KTH, Div Land & Water Resources Engn, S-10044 Stockholm, Sweden.;Koya Univ, Dept Civil Engn, Fac Engn, KOY45, Koya, Kurdistan Regio, Iraq..
    Earon, Robert
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. Royal Inst Technol KTH, Div Land & Water Resources Engn, S-10044 Stockholm, Sweden..
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. Royal Inst Technol KTH, Div Land & Water Resources Engn, S-10044 Stockholm, Sweden..
    Detecting Seasonal Flow Pathways in Road Structures Using Tracer Tests and ERT2018In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 229, no 11, article id 358Article in journal (Refereed)
    Abstract [en]

    Roads and traffic can be a source of water-bound pollutants, which can percolate through the unsaturated zone to groundwater. Deicing salt is widely used on roads in northern Europe during winter and is usually applied at a time when the temperature is below zero and the soil is partly frozen. Understanding the mechanism by which water-bound pollutants such as deicing salt are transferred from roads to groundwater is highly important for groundwater protection, environmental sustainability and road maintenance. Electrical resistivity tomography (ERT) can be used for tracing the infiltration of deicing salt in different seasons, including the frozen period, as a step towards identifying pollutant infiltration pathways. In this study, a tracer-ERT monitoring method and analytical process was developed and evaluated for use in investigating and demonstrating deicing salt infiltration pathways in road structures in different seasons and weather conditions. The method involves using dissolved sodium chloride as a tracer and monitoring its infiltration using a multi-electrode array system. The tracer tests were performed at the same location in different seasons over a 1-year period. The results indicated high seasonal variation in percolation pattern and flow velocity, with large decreases in December (winter), most likely due to preferential flow paths within the road shoulder. These findings can be applied to other water-soluble pollutants that move from the road surface to groundwater.

  • 40.
    Rasul, Hedi
    et al.
    Koya University.
    Wu, Mousong
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Hansson, Klas
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Two-dimensional model for heat and moisture dynamics in Nordic roads: Model set-up and sensitivity analysisIn: Cold Regions Science and Technology, ISSN 0165-232X, E-ISSN 1872-7441Article in journal (Other academic)
    Abstract [en]

    Modeling moisture and heat changes in road layers is important for understanding road hydrology, but also for better construction and maintenance of roads. The modeling task is more complicated in cold regions, due to the water-ice phase change in wintertime. This paper presents a two-dimensional model based on a road section. The water and heat transport equations, including freezing/thawing and vapor flow, were implemented within the COMSOL Multiphysics tool. Parameters were optimized from modeling results based on measured soil moisture and temperature at a road test station near Stockholm. Impacts of phase change in the model were assessed. The results showed that model developed can accurately predict temperature changes, water and ice content in different road layers based on pressure head and temperature gradient. The model of water dynamics performs much better than predicting the average water content in the upper road layer. Parameters related to soil water retention curve are optimized and most parameters influence water and heat change in the same direction, except the thermal conductivity of soil. The optimized parameters based on moisture content and temperature data from the sensors in the road section can be used in this model for testing different road materials and geometries. The model provides a clear understanding of water and heat transfer in roads with ideal boundary and initial conditions. For a better understanding of road heat and moisture dynamics, more physical processes can be added to the model in future work by coupling snow melt and surface flow models.

  • 41.
    Rasul, Hedi
    et al.
    Koya University.
    Zou, Liangchao
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Resources, Energy and Infrastructure.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Monitoring of moisture and salinity content in an operational road structure by electrical resistivity tomography.In: Near Surface Geophysics, ISSN 1569-4445, E-ISSN 1873-0604Article in journal (Refereed)
    Abstract [en]

    Moisture dynamics in road systems significantly affect road structure design and maintenance. This study analysed moisture dynamics in a cross-section of motorway (the E18) in Sweden during a one-year period through in situ monitoring using electrical resistivity tomography (ERT). The monitoring methodology was assessed since resistivity can provide a good proxy for monitoring moisture in the road structure. Monthly electrical resistivity was calculated by inverting resistivity data along a pre-installed electrical resistivity line beneath the surface asphalt layer of the road at the test site. The electrical resistivity data were then statistically analysed and correlated with local climate data, i.e. precipitation and temperature, and with ground parameters such as moisture content. The results showed high variation in resistivity in the road surface layer and road shoulders depending on weather conditions, water flow and other surface activities. In general, negative correlations between electrical resistivity and precipitation were observed. The results also indicated possible retardation of de-icing salt after accumulating in the top layer during winter. These findings advance understanding of the moisture dynamics in roads and can help improve pavement design in response to future climate change.

  • 42.
    Renman, Agnieszka
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Kholoma, Ezekiel
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Zhang, Wen
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Leachability and plant -availability of phosphorus in post-sorption wastewater filters fortified with biochar2018In: Environmental technology, ISSN 0959-3330, E-ISSN 1479-487XArticle in journal (Refereed)
    Abstract [en]

    Sand and gravel are widely applied for filtering pre- or primary-treated wastewater in small-scale wastewater treatment (SWT) systems. However, ecological materials continue to attract increasing interest in use as retrofits for achieving better performance in removing dissolved contaminants and recovering nutrients from wastewater. In this study, we assessed the plant availability and leachability of phosphorus (P) from sand (Sa) and gas concrete (GC) media previously fortified with biochar (BC) and used for phosphorus (P) removal in laboratory-scale packed bed reactors and field-scale constructed filter beds. Batch and leaching experiments were conducted, with distilled water and ammonium lactate (AL) solutions (1:20 solid–liquid (w/v) ratio) applied as extractants. In the findings, reference (Sa) and fortified (Sa-BC) sand filters leached 11.2 and 20.5 mg P kg−1 respectively, to percolating water while the P seemed less likely to leach from GC systems. Extraction with AL showed that P retained in GC was plant-available and that GC could release up to 90 mg kg−1 of the bound mass. These findings highlight the need to evaluate risks of nutrient leaching from filter media for SWT systems especially where groundwater and surface water are final recipients of such effluents. For greater sustainability of use of the media, the weakly bound P in media such as Sa and BC and strongly bound in media such as GC types of materials may be recovered by recycling the spent material to agriculture. However, this may require re-design of the treatment system especially with respect to particle size to make recycling technically feasible.

  • 43.
    Robiglio, Alessio
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Nitrogen removal from municipal wastewater by mainstream Partial Nitritation/Anammox process2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Mainstream Partial Nitritation/Anammox, also known as Mainstream Deammonification, is a promising technology for future wastewater purification that aims to remove nitrogen from wastewater in order to prevent the eutrophication. It is less costly than the traditional nitrification/denitrification process and it heads towards the direction of converting the WWTPs from energy consuming into energy producing facilities.

     

    This Master’s thesis is based on a study regarding the nitrogen removal from mainstream wastewater. It was conducted at Hammarby Sjöstadsverk that is a research facility in the area of the Henriksdal Waste Wastewater Treatment Plant in Stockholm. Three parts of the study were developed. The main one had the purpose to evaluate the process performances of a biological pilot-scale IFAS reactor used for Mainstream Deammonification that was operated from October 2017 to March 2018. This evaluation was addressed to comprehend how the pilot-scale reactor works at different operational conditions. The remaining studies analysed the progress of the pilot-scale reactor in relation to different factors and to the settling properties of the activated sludge used in the process.

     

    It was found that the process performances improved by changing the aeration pattern from 40 to 50 minutes for non-aeration time and from 20 to 10 minutes for aeration time and by increasing the dissolved oxygen set-point from 0.6 to 1.0 mg/L. The enhancement of the performances consisted in an inhibition of nitrite oxidizing bacteria and rise of the total nitrogen removal efficiency. In addition, anammox biofilm was observed to grow on the carriers and it was observed that the activated sludge did not have good settling properties.

  • 44.
    Rostvall, Ande
    et al.
    Dept. of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden.
    Zhang, Wen
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Dürig, W.
    Dept. of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Wiberg, Karin
    Dept. of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden.
    Ahrens, Lutz
    Dept. of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden.
    Gago-Ferrero, Pablo
    Dept. of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden.
    Removal of pharmaceuticals, perfluoroalkyl substances and other micropollutants from wastewater using lignite, Xylit, sand, granular activated carbon (GAC) and GAC+Polonite® in column tests – Role of physicochemical properties2018In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 137, p. 97-106Article in journal (Refereed)
    Abstract [en]

    This study evaluated the performance of five different sorbents (granular activated carbon (GAC), GAC + Polonite® (GAC + P), Xylit, lignite and sand) for a set of 83 micropollutants (MPs) (pharmaceuticals, perfluoroalkyl substances (PFASs), personal care products, artificial sweeteners, parabens, pesticide, stimulants), together representing a wide range of physicochemical properties. Treatment with GAC and GAC + P provided the highest removal efficiencies, with average values above 97%. Removal rates were generally lower for Xylit (on average 74%) and lignite (on average 68%), although they proved to be highly efficient for a few individual MPs. The average removal efficiency for sand was only 47%. It was observed that the MPs behaved differently depending on their physicochemical properties. The physicochemical properties of PFASs (i.e. molecular weight, topological molecular surface area, log octanol water partition coefficient (Kow) and distribution coefficient between octanol and water (log D)) were positively correlated to observed removal efficiency for the sorbents Xylit, lignite and sand (p &lt; 0.05), indicating a strong influence of perfluorocarbon chain length and associated hydrophobic characteristics. In contrast, for the other MPs the ratio between apolar and polar surface area (SA/SP) was positively correlated with the removal efficiency, indicating that hydrophobic adsorption may be a key feature of their sorption mechanisms. GAC showed to be the most promising filter medium to improve the removal of MPs in on-site sewage treatment facilities. However, more studies are needed to evaluate the removal of MPs in field trials.

  • 45.
    Sterner, Martin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Ribeiro, Mauricio Sodre
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Edlund, Ulrica
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Cyclic fractionation process for Saccharina latissima using aqueous chelator and ion exchange resin2017In: Journal of Applied Phycology, ISSN 0921-8971, E-ISSN 1573-5176, Vol. 29, no 6, p. 3175-3189Article in journal (Refereed)
    Abstract [en]

    A new approach to process Saccharina latissima algal biomass was developed using sodium citrate and a polyvalent cation-specific resin to sequentially extract the alginate into several usable fractions. The fractionation was performed in a cyclic manner, utilizing a stepwise removal of the native polyvalent ions present in the algae to isolate fractions of alginate with different solubility in the presence of these ions. Sodium citrate was used in different concentrations in the extraction solution to remove polyvalent cations to adjust the alginate liberation while AMBERLITE IRC718 resin was added to further remove these ions and regenerate the extraction solution. Alginate was recovered by acid precipitation and analyzed for its uronic acid composition and molecular weight, and the carbohydrate compositions of the insoluble and soluble parts of the algal biomass residue were determined. Finally, the fractionation method was assessed with a life cycle analysis to determine the energy and water efficiency as well as the greenhouse gas emissions and the results were compared to conventional alkaline extraction. The results indicate that the energy and water use as well as the emissions are considerably lower for the cyclic extraction in comparison with the conventional methods.

  • 46.
    Suleiman, Lina
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Urban and Regional Studies.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Saurí, D.
    Palau-Rof, L.
    García Soler, N.
    Papasozomenou, O.
    Moss, T.
    Diverse pathways—common phenomena: comparing transitions of urban rainwater harvesting systems in Stockholm, Berlin and Barcelona2019In: Journal of Environmental Planning and Management, ISSN 0964-0568, E-ISSN 1360-0559Article in journal (Refereed)
    Abstract [en]

    Urban rainwater management is the terrain of varied initiatives that challenge existing drainage systems. The initiatives that this article refers to as Urban Rainwater Harvesting (URH), promise a more sustainable urban water approach; however, they remain isolated “niche” projects. The article aims to investigate challenges and opportunities for mainstreaming alternative URHs as sociotechnical systems (STS). It identifies six analytical categories: context, actors, instruments, processes/dynamics, outputs and impacts as a framework for the analyses of URH projects in Stockholm, Berlin and Barcelona. Despite the diversity of socio-spatial contexts, driving forces, purposes, instruments used, technical designs and scale of URH projects, relevant factors for a breakthrough of these systems are discussed. Even though URHs have not yet become a common component of rainwater management in any of the cities, context-specific combinations of these factors are found to be essential if these systems are to become complementary options for the sustainable management of rainwater in cities.

  • 47. Vega, M. A.
    et al.
    Kulkarni, H. V.
    Mladenov, N.
    Johannesson, K.
    Hettiarachchi, G. M.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. The University of Southern Queensland, Australia.
    Kumar, N.
    Weeks, J.
    Galkaduwa, M.
    Datta, S.
    Biogeochemical controls on the release and accumulation of Mn and As in shallow aquifers, West Bengal, India2017In: Frontiers in Environmental Science, ISSN 2296-665X, Vol. 5, no JUN, article id 29Article in journal (Refereed)
  • 48.
    von Bahr, Maximilian
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Gomez Bergström, Ida
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Investigation of the origin of salt in coastal aquifers and assessment of metals in the aquatic environment: River Drin and River Vjosa, Albania2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The preservation of freshwater aquifers is one important task of managing natural resources today. Intrusion of saltwater from the sea into the groundwater might occur in coastal-near areas and can affect the freshwater quality negatively. One such risk area is the Adriatic coast line of Albania, a country predominantly rich in freshwater resources due to the numerous rivers flowing from the mountains in the east towards the sea. The coastal areas are mainly used for agricultural activities were groundwater is an important resource for irrigation purposes. This study was therefore partly conducted in Albania where samples of groundwater and river waters were collected from the river deltas of Drin and Vjosa in order to investigate the origin of the salt and to assess the bioavailable metal concentrations of nickel and zinc. Both on-site tests and off-site tests, in laboratories, were conducted. In the laboratory, the samples were analysed for oxygen and deuterium isotope data. The results were used to assess the origin of the oxygen content as the method of investigating the origin of the salt uses the oxygen isotope as a tracer. Anion and cation concentrations were analysed as well as the concentrations of metals. These were used as input data to Visual Minteq, a model used to calculate the metal speciation of waters, and a Biotic Ligand Model used to calculate the bioavailable concentrations and the HC5 concentrations. The isotope analysis yielded results similar to previous studies conducted in the nearby area indicating that the salt does not have oceanic origin but meteorological. The bioavailable concentrations were in most sample sites lower than the calculated HC5 concentrations indicating that there is a sufficient buffering system present even though there are several mining activities upstream of the sample sites that could have affected the water quality.

    This study concludes that the origin of salt is of meteoric origin and not from seawater intrusion. The bioavailable concentrations do not pose a threat as the concentrations are under the HC5 concentrations for all sites but one.

    In order to deepen the understanding and knowledge of the water qualities in these areas, future studies should focus on a continuous measuring period lasting for example over the whole year minimizing any seasonal variations of the sampled data. Other methods such as geophysical measures could also contribute to a wider analysis of the groundwater condition.

  • 49.
    Zhang, Wen
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    An add-on filter technique to improve micropollutant removal and water quality in on-site sewage treatment facilities2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Onsite sewage treatment facilities (OSSFs) in Sweden currently release significant amounts of nitrogen (N) and phosphorus (P) into groundwater or/and receiving water bodies. Micropollutants (MPs) have been found in both surface water and groundwater, indicating insufficient removal of MPs by OSSFs. Two laboratory-scale column experiments, followed by a field experiment, were performed to study removal of a set of organic MPs by organic and inorganic sorbents. The set covered different product categories, e.g. an artificial sweetener, organophosphates, parabens, personal care products, perfluoroalkyl substances (PFASs), pesticides, pharmaceuticals, a plasticiser, a polymer impurity, stimulants and surfactants. An experiment using five organic and five inorganic sorbents showed that coal-based organic sorbents performed better than natural fibre and inorganic sorbents in removal of MPs, with 20% higher removal efficiency on average. Five sorbents were selected for a long-term column experiment examining 31 MPs. Physical properties and chemical structure of the sorbents, namely pore structure and surface functional groups, were found to be correlated to their capacity for removal of MPs. Molecular weight, solvent-accessible area, octanol-water partition coefficient and distribution-coefficient of PFASs were found to be strongly positively correlated with their removal by some sorbents. Organic sorbents with good performance in removal of MPs and a conventional sand bed showed limited ability to remove P, while calcium-rich sorbents increased P removal greatly. Two sorbents, granulated activated carbon (GAC) and xyloid lignite (Xylit), were tested for 24 weeks in an add-on filter for effluent from a soil treatment system and found to significantly improve removal of MPs. A replaceable add-on unit for removal of MPs from OSSF effluent is recommended and should contain an organic sorbent such as GAC or Xylit.

  • 50.
    Zhang, Wen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Removal of 31 organic micropollutants and phosphorus by filter media in a column experiment using household wastewaterManuscript (preprint) (Other academic)
    Abstract [en]

    A bench-scale column experiment was performed to study the removal of 31 selected organic micropollutants (MPs) by lignite, xyloid lignite (Xylit), granular activated carbon (GAC), Polonite® and sand over a period of 12 weeks. The MPs analysed included an artificial sweetener, biocides, fragrances, organophosphates, perfluoroalkyl substances (PFASs), pesticides, pharmaceuticals, a plasticiser, a polymer impurity, a preservative, a rubber additive, a surfactant and UV stabilisers. The removal of several MPs improved after four weeks in sand, Xylit, GAC and lignite which may be related to increased biological activity and biofilm development. In total 29 out of the 31 MPs showed a removal efficiency of >90% by GAC with an average removal of 97 ± 6%. Xylit and lignite were less efficient with an average removal of 80 ± 28% and 68 ± 29%, respectively. However, Xylit and lignite performed well for relatively hydrophobic (log Kow ≥3) MPs (i.e. hexachlorobenzene, galaxolide and tributylphosphate) with an average removal efficiency of 90 ± 5 % and 95 ± 4 %, respectively. The removal efficiency obtained with Xylit and lignite of moderately hydrophilic MPs (i.e. tris-(2-chloroethyl)phosphate), highly hydrophilic (i.e. sucralose) and negatively charged (i.e. PFOS and diclofenac) were lower (67 ± 35% for Xylit and 49 ± 26% for lignite). The organic sorbents were found to have more functional groups at their surfaces, which might explain the higher adsorption of MPs to these sorbents. GAC and sand had limited ability to remove phosphorus (12 ± 27% and 14 ± 2%, respectively), while the calcium-silicate material Polonite® precipitated phosphorus efficiently and increased the total phosphorus removal from 12% to 96% after the GAC filter.

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