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  • 1. 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.

  • 2.
    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.

  • 3.
    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.

  • 4. 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.

  • 5.
    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.

  • 6.
    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.

  • 7.
    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.

  • 8. 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.

  • 9. 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.

  • 10.
    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.

  • 11.
    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.

  • 12.
    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.

  • 13.
    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.

  • 14.
    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.

  • 15.
    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.

  • 16.
    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.

  • 17. 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)
  • 18.
    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.

  • 19.
    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.

  • 20.
    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 micropollutants and nutrients in household wastewater using organic and inorganic sorbentsIn: Desalination and Water Treatment, ISSN 1944-3994, E-ISSN 1944-3986Article in journal (Refereed)
    Abstract [en]

    The efficiency of five organic and five inorganic sorbents in removing 19 organic micropollutants (MPs), phosphorus, nitrogen, and dissolved organic carbon (DOC) was tested in a two-week column experiment using household wastewater spiked with pharmaceuticals (n = 6), biocides/pesticides (n = 4), organophosphates (n = 3), a fragrance, a UV-stablizer, a food additive,a rubber additive, a plasticizer and a surfactant. Two types of granular activated carbon (GAC), two types of lignite, a pine bark product, and five mineral-based sorbents were tested. All the organic sorbents except pine bark achieved better removal efficiencies of DOC (on average, 70 ± 27%) and MPs (93 ± 11%) than the inorganic materials (DOC: 44 ± 7% and MPs: 66 ± 38%). However, the organic sorbents (i.e. GAC and xyloid lignite) removed less phosphorus (46 ± 18%), while sorbents with a high calcium or iron content (i.e. Polonite® and lignite) generally removed phosphorus more efficiently (93 ± 3%). Ammonium-nitrogen was well removed by sorbents with a pH between 7 and 9, with an average removal of 87%, whereas lignite (pH 4) showed the lowest removal efficiency (50%). Some MPs were well removed by all sorbents (≥97%) including biocides (hexachlorobenzene, triclosan and terbutryn), organophosphates (tributylphosphate, tris-(1,3-dichloro-2-propyl)phosphate and triphenylphosphate) and one fragrance (galaxolide). The pesticide 2,6-dichlorobenzamide and the pharmaceutical diclofenac were poorly removed by the pine bark and inorganic sorbents (on average, 4%), while organic sorbents achieved high removal of these chemicals (87%).

  • 21.
    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.
    Wastewater purification and removal of micropollutants in a soiltreatment system and by subsequent filtration through activatedcarbon and xyloid lignite – a field experimentManuscript (preprint) (Other academic)
    Abstract [en]

    Soil treatment systems (STS) are often used in rural areas to remove nutrients and microorganisms from wastewater. These and other facilities designed for on-site sewage treatment should also have the capacity to remove micropollutants (MPs), i.e. pharmaceuticals, personal care products, detergents, polymer additives, and other synthetic organic compounds. In a six-month study on a medium-scale STS with two add-on filters installed to purify the effluent, possible removal enhancement of MPs, phosphorus (Ptot) and ammonium-nitrogen (NH4-N) was examined. The filters contained granular activated carbon (GAC) and xyloid lignite (Xylit). A total of 58 compounds were detected, comprising artificial sweeteners (n = 2), organophosphates (n = 7), parabens (n = 3), personal care products (n = 7), pesticides (n = 2), perfluoroalkyl substances (PFAS) (n = 3), pharmaceuticals (n = 27), a plasticiser, a polymer impurity, a rubber additive, stimulants (n = 3) and a surfactant. The concentrations in influent water to the STS ranged from 1.3 ng L-1 (ranitidine) to 110 μg L-1 (acetaminophen). Mean removal rate of MPs by the STS was 49 ± 56 %. The add-on filters significantly improved (ANOVA, p<0.001) removal of MPs, despite treating a high hydraulic load (2350 L m-2 day-1). The GAC and Xylit filters removed 98 ± 6 % and 87 ± 28 %, respectively, demonstrating the potential of these materials to reduce MPs in STS effluent to very low concentrations. The add-on filters did not improve removal of P and NH4-N from STS effluent, but the GAC-based filter improved removal of organics (COD) by 5%. 

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