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  • 151.
    Barås, Madeleine
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    Assessing the environmental sustainability of an apparel supply chain: the development of a conceptual model based on a comparative study of preferred tools and actual practices2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The apparel and textile industry is one of the largest in the world and is characterised by complex, global supply chains, water and chemical intensive processes as well as environmentally harmful raw material extraction and production. Because of this, environmental sustainability has become a key issue for the businesses in recent years. With this in mind, and considering an increasing demand for textile and apparel goods, the industry is in urgent need of improving the environmental footprint of its products. However, lack of transparency and available data throughout apparel supply chains decrease chances of producing accurate sustainability assessments, which in turn obstruct improvement measures. Moreover, companies often lack the in-house competence required to manage and create strategies for sustainability assessments.

    In this study an overview of an apparel supply chain is provided, highlighting phases, sub phases, input and environmental indicators. Appropriate tools for assessing the environmental sustainability of such a supply chain are inventoried and examined. Based on a case study, a literature review and a stakeholder opinion assessment, misalignments between actual practices within an apparel company and recommended practices of the researcher and stakeholder communities are uncovered. These identified misalignments enabled the development of a conceptual model, aiming at facilitating the process of developing an environmental sustainability assessment strategy within an apparel company. 

  • 152.
    Basmaci, Benjamin
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Improving indoor thermal comfort in residential buildings in Andean regions of Peru2018Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    In the Peruvian Andes, inadequate housing represents an important problem for the local rural people. Over 3000 meters above sea level, communities suffer from very low indoor temperatures this becomes an issue which affects the health and indoor thermal comfort of the building. At early winter mornings, outdoor temperatures can occasionally go down to -15°C and indoor temperatures can drop below zero. Previous work in the field has been done by the Pontifical Catholic University of Peru PUCP, to address thermal comfort in Langui, Peru involving participatory design techniques, multidisciplinary approaches and a focus on sustainability. Their most recent design is based on an attached passive solar heating system similar to a Trombe wall.

    The effect of housing environment on human health has been an acknowledged issue for many years. In the area, the occupants live with high levels of air infiltration, dirt floor (soil), simple windows, metallic or wood doors, roof most commonly made of corrugated metal sheets, adobe walls, no additional insulation attached and no house heating system. This thesis aims to contribute to a current body of research on thermal comfort and provide insights on how the building environment in Langui can be improved.

    The main objective is to improve thermal comfort in residential buildings in Andean regions of Peru. An improvement was made by installing a Heat Transfer Rocket which increased the temperature while the relative-humidity stayed steady. Overall, the study shows that indoor improvements can increase thermal comfort in Andean regions of Peru.

  • 153.
    Bast, Sigvard
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Schück, Fredrik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Laver, då som nu: En fallstudie om efterbehandlingens vikt vid planering av gruvor2019Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Ökad efterfråga på koppar har inneburit att man börjat prospektera områden där kopparhalten är låg. Ett sådant område är Laver i Älvsbyn kommun där Boliden vill etablera ett dagbrott i vad som förut var ett gruvsamhälle men nu står övergivet. Den planerade gruvan orsakar konflikter med närliggande rennäring, Natura 2000-områden samt har konsekvenser för miljön och samhället i Älvsbyn. Denna rapport undersöker effekterna av den tidigare och planerade gruvan i Laver med fokus på hur efterbehandling ska gå till och hur den påverkar olika aktörer. Materialet är hämtat från litteratur, intervjuer och ett fältarbete i Laver och har resulterat i en scenarioanalys där påverkan på miljön, rennäring och samhället värderats. Om en gruva etableras i Laver kan gruvavfallet tas hand om av Boliden och det finns idéer om hur en efterbehandling kan tillgodose kommunens behov men projektet riskerar att slå ut rennäringen. Det är därför viktigt att konsekvenserna vägs utifrån ett helhetsperspektiv där alla aktörers intressen tillgodoses.

  • 154.
    Bedoire Fivel, Johannes
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Achieving a decarbonised European steel industry in a circular economy2019Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    As part of the European Union’s climate commitment including the adoption of the Paris agreement, the European commission has developed a long-term strategy with the goal to reach net zero CO2emissions in 2050. To achieve this, a transformation of the European industry is necessary, as it represents 30% of EU’s total emissions. A major challenge will be to cut emissions in the CO2intensive steel industry, which is considered hard to abate. To reach the Paris agreement, deep emission cuts are necessary to occur within a decade, before cumulative emissions are too high.

    Today, about 60% of all steel in the EU is produced using coke as feedstock, a process resulting in large CO2 emissions. A new process in which hydrogen is used instead of coke is under development, with no direct CO2 emissions as result. The implementation of such technologies can help shift the production from fossil based to renewable, with declining emissions as a result. Until now, most abatement methods are focused on the supply side, finding technical solutions that can reduce emissions. This study shows that technology can play an important role in the transformation of the steel industry but will not alone achieve the necessary reductions fast enough.

    To achieve near-zero emissions in the steel industry, the solution set needs to widen to include demand side measures. The results show that circular economy principles that promote higher shares of recycled steel and reduced losses have the potential to lower total demand. This also applies for circular business models, by which incentives for higher utilisation and lifetimes of products can be created. In this report, demand-side measures are analysed using a stock-based steel demand model. It is estimated that demand-side measures can decrease the steel demand by 27% in 2050, compared to a business as usual scenario. Applying circular principles would also increase the share of recycled steel being produced from old steel scrap, a process far less CO2 intensive than virgin production.

    The findings are, that demand side measures can provide immediate deep emission cuts necessary, saving time before new technologies are implemented. The lower steel demand also helps making the transition from fossil to fossil-free steel production easier. By a combination of demand side reductions and hydrogen-DR the steel industry in Europe can reach near-zero emissions by 2050.

  • 155. Begum, Shamim A.
    et al.
    Hyder, A. H. M. Golam
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Vahdat, Nader
    Adsorption isotherm and kinetic studies of As(V) removal from aqueous solution using cattle bone char2016Inngår i: Journal of Water Supply: Research and Technology - Aqua, ISSN 0003-7214, E-ISSN 1365-2087, Vol. 65, nr 3, s. 244-252Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The As(V) adsorption onto bone char was investigated as a function of bone char dosage, pH and contact time in batch tests. The initial As(V) concentrations were varied from 0.1 to 1 mg/L to evaluate the adsorption kinetics and isotherm. The As(V) concentrations were analyzed using a graphite furnace atomic absorption spectrophotometer. The highest As(V) removal was found to be 62% after 3 d using 3 g bone char at a pH level of 4.0 for 0.5 mg/L As(V) concentration. The maximum adsorption capacity was 0.13 for 1 mg/L As(V) concentration. A Langmuir isotherm and second order adsorption kinetics were observed for As(V) adsorption.

  • 156.
    Belaieff, Vera
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Barns mobilitet: En analys av barns skol- och fritidsresor samt det kommunala arbetet kring de respektive resorna2019Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Barn reser mycket, precis som vuxna människor gör. En stor andel av barnens resor går till och från skolan, men utöver det sker även mycket fritidsresor till bland annat föreningsliv och idrottsanläggningar. Hur barn reser i vardagen påverkar både barns hälsa och utvecklande av självständighet. Med anledning av detta handlar detta examensarbete om just barns mobilitet och hållbara vardagsresor. Syftet är att lyfta barns olika resande samt inspirera och ta fram underlag för ett vidare arbete med barns mobilitet.

    Studien utfördes främst genom litteraturstudier samt enkätundersökningar. En resvaneundersökning gjordes tillsammans med Järfälla kommun för elever och föräldrar på Skälbyskolan, där frågorna undersökte resorna till skolan samt fritidsaktiviteter. En ytterligare enkät skickades ut till kommuner i nätverket ResSmart i Stockholmsområdet, och undersökta huruvida kommunerna arbetar med skol- respektive fritidsresor eller inte samt anledningar till detta.

    Resultatet av undersökningarna visar att gång och cykel är de vanligaste färdsätten till skolan, oftast själv eller tillsammans med jämnåriga. Skillnaden är dock stor gällande hur många barn som cyklar beroende på årstid, där endast en mycket liten andel cyklar på vinterhalvåret. Till fritidsaktiviteter är det överlägset vanligaste färdmedlet bil, vilket leder till att barnens självständighet kring dessa resor är låg. Anledningen till skjuts till fritidsaktiviteter är främst avståndet men även kopplat till tiden på dygnet och det generella familjepusslet. Vid skjuts till skolan uppgavs anledningen vara tidsbrist och att föräldrarna ändå skulle resa vidare med bilen.

    Vid jämförelse mellan förortsskolan Skälbyskolan och Gustav Vasa skola i Stockholms innerstad, syns att gång är det vanligaste färdsättet i båda områden. Däremot sker varken skjutsning eller cykling till Gustav Vasa skola, trots att anledningen till skjuts när den väl sker är densamma som vid Skälbyskolan.

    Gällande det kommunala arbetet är det fler kommuner som arbetar med hållbara skolvägar än barns fritidsresor. Dessutom skiljer sig arbetssättet, och vid arbete med fritidsresor nämns endast fysiska åtgärder och mjuka åtgärder saknas helt.

    Utifrån resultatet har åtgärdsförslag presenterats för ett utvecklat arbete inom området. För skolresor bör fokus ligga på att påverka föräldrarnas resvanor samt underlätta för vintercyklande. För fritidsresor föreslås istället att mycket åtgärder kopieras från skolvärlden, och där arbetet bör starta med inventering och resvaneundersökningar. Vidare föreslås att mjuka åtgärder ska introduceras, samt att komplexa och långsiktiga åtgärder som fritidsbussar och tätare stadsplanering är nödvändiga.

    Slutligen menar studien att vidare arbeten och arbete krävs för ett fortsatt utvecklat arbete med barnsresor. Området fritidsresor behöver lyftas både i underlag och information men även i medier och i större forum.

  • 157. Bengtsson, Magnus
    et al.
    Alfredsson, Eva
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Strategiska hållbarhetsstudier.
    Cohen, Maurie
    New Jersey Inst Technol, Newark, NJ 07102 USA..
    Lorek, Sylvia
    Sustainable Europe Res Inst, Cologne, Germany..
    Schroeder, Patrick
    Inst Dev Studies, Brighton, E Sussex, England..
    Transforming systems of consumption and production for achieving the sustainable development goals: moving beyond efficiency2018Inngår i: Sustainability Science, ISSN 1862-4065, E-ISSN 1862-4057, Vol. 13, nr 6, s. 1533-1547Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The United Nations formulated the sustainable development goals (SDGs) in 2015 as a comprehensive global policy framework for addressing the most pressing social and environmental challenges currently facing humanity. In this paper, we analyse SDG 12, which aims to ensure sustainable consumption and production patterns. Despite long-standing political recognition of this objective, and ample scientific evidence both on its importance and on the efficacy of various ways of promoting it, the SDGs do not provide clear goals or effective guidance on how to accomplish this urgently needed transformation. Drawing from the growing body of research on sustainable consumption and production (SCP), the paper identifies two dominant vantage pointsone focused on promoting more efficient production methods and products (mainly through technological improvement and informed consumer choice) and the other stressing the need to consider also overall volumes of consumption, distributional issues, and related social and institutional changes. We label these two approaches efficiency and systemic. Research shows that while the efficiency approach contains essential elements of a transition to sustainability, it is by itself highly unlikely to bring about sustainable outcomes. Concomitantly, research also finds that volumes of consumption and production are closely associated with environmental impacts, indicating a need to curtail these volumes in ways that safeguard social sustainability, which is unlikely to be possible without a restructuring of existing socioeconomic arrangements. Analysing how these two perspectives are reflected in the SDGs framework, we find that in its current conception, it mainly relies on the efficiency approach. On the basis of this assessment, we conclude that the SDGs represent a partial and inadequate conceptualisation of SCP which will hamper implementation. Based on this determination, this paper provides some suggestions on how governments and other actors involved in SDGs operationalisation could more effectively pursue SCP from a systemic standpoint and use the transformation of systems of consumption and production as a lever for achieving multiple sustainability objectives.

  • 158.
    Berger, Malin
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    STADSODLINGAR: En litteraturstudie kring hållbarhet och byggnadsintegrerade stadsodlingar i Afrika och Nordamerika2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Jordens befolkning ökar i snabb takt och stadsodlingar kan vara ett sätt att förse den ökande populationen med mat. Hur byggnadsintegrerade stadsodlingar, med fokus på tak, kan kopplas till hållbarhet undersöks i denna rapport. Den nuvarande situationen i Afrika och Nordamerika undersöks och frågeställningen som besvaras är: Hur skiljer sig prioriteringen av olika dimensioner av hållbarhet vid olika förutsättningar för urbana byggnadsintegrerade odlingar i Afrika och Nordamerika?

    Vilka aspekter av hållbarhet som kopplas till byggnadsintegrerade stadsodlingar bestäms till ekologiska, sociala och ekonomiska. Stadsodlingar kan också delas in i fyra olika verksamhetsplaner, av vilka institutionella odlingar, kommersiella odlingar och community farms analyseras.

    Resultatet visar att Afrika och Nordamerika har olika förutsättningar för att stadsodling ska vara en hållbar lösning. Afrika består idag av 1.1 miljarder människor vilket beräknas stiga till 2.4 miljarder år 2050. Klimatet är torrt på de flesta platser och en stor del av befolkningen lever i fattigdom och svält. Nordamerika har ett tempererat klimat med fyra årstider, och befolkningen kommer att ligga på en stabil nivå fram till år 2050. Nordamerika räknas som ett mer utvecklat land, vilket innebär att de ekonomiska förutsättningarna här är större än de är i Afrika. Det finns en större andel stora odlingar i Nordamerika jämfört med Afrika, där odlingarna är mindre till ytan. Det finns också fler exempel på byggnadsintegrerad stadsodling i Nordamerika än i Afrika.

    Slutsatserna blir att byggnadsintegrerade stadsodlingar har bättre potential att utvecklas i Nordamerika då de kräver en stor investeringskostnad vid anläggning. För att byggnadsintegrerade stadsodlingar ska bli en mer hållbar och utbredd lösning både i Afrika och Nordamerika krävs att anläggningskostnaderna sänks med hjälp av nya tekniker.

    Community farms och institutionella odlingar prioriterar social hållbarhet medan kommersiella odlingar främst satsar på ekologisk och ekonomisk hållbarhet.

    Stadsodlingar är och har möjlighet att bli en allt viktigare del i matförsörjningen i städer. Då städerna förtätas minskar tillgänglig odlingsyta och andra lösningar måste användas. Byggnadsintegrerad stadsodling är en hållbar lösning både ekologiskt och socialt, och kan även kostnaderna för en byggnadsintegrerad odling minska kan dessa odlingar vara till stor hjälp för att minska svält och fattigdom. 

  • 159. Berger, T.
    et al.
    Mathurin, F. A.
    Gustafsson, Jon Petter
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik. Swedish University of Agricultural Sciences, Sweden.
    Peltola, P.
    Åström, M.E.
    The impact of fluoride on Al abundance and speciation in boreal streams2015Inngår i: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 409, s. 118-124Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The impact of fluoride on the abundance and speciation of aluminium (Al) was investigated in three boreal streams characterised by overall high concentrations of fluoride and dissolved organic matter. Stream-water sampling was carried out several times a year for at least 4 years, and a chemical equilibrium model (Visual MINTEQ) was applied in order to model the proportion of colloidal and organically/inorganically complexed Al in the waters. The Al concentrations in filtered (0.45 μm) water samples were inversely correlated with pH, and reached values up to approximately 1. mg/L during low pH conditions (pH < 6.0). In a stream with high fluoride concentrations, as compared to a similar stream with only moderately elevated fluoride concentrations, the Al concentrations were consistently elevated. For the stream with high concentrations of fluoride and Al, the model predicted both high concentrations and proportions of Al-fluoride complexation. This prediction indicates that high fluoride levels contribute to raise both the Al abundance and the ratio of inorganic to organic Al complexation in stream water. In contrast, for another stream with high fluoride concentrations and consistently high (near neutral) pH, there was no evidence of fluoride affecting Al concentration or complexation. These results show that it is important to focus future studies on the role of high levels of dissolved fluoride on both the speciation and the toxicity of Al in stream water.

  • 160.
    Berggren, Anders
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    LCA of Egg Phospholipids2013Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Egg phospholipids are a group of fats or lipids in the egg yolk, commonly used as emulsifiers in the chemical industry to facilitate the dissolving of substances. The pharmaceutical company Fresenius-Kabi manufactures this product and seeks a better understanding of the product’s major environmental impacts in order to comply with the ISO 14001 requirements, communicate its environmental performance and choose raw materials that result in lower environmental impacts.

    The aim of this study is to quantify and identify environmental impacts that occur in the life cycle of Fresenius-Kabi’s egg phospholipids product, and to suggest improvements on how the impacts could be reduced. The aim has been reached by following the life cycle assessment methodology. The life cycle consists of egg, egg yolk powder and egg phospholipids production. The major inputs to the life cycle include fertilizers, pesticides, hen feed, fuel oil and solvents. The major outputs are hen manure, egg residues, air and water emissions.

    The results show that the greatest impacts are generated in the production of hen feed, solvent feedstocks, the hen manure handing and the final egg phospholipids production. The most severe environmental impacts are found in the human toxicity and eutrophication impact categories. Pesticide and fertilizers usage in the cultivation of hen feed and solvent feedstocks generate phosphorus, manganese and arsenic emissions, which are emission substance sources in the human toxicity impact category. In addition, nitrate and phosphate emissions from fertilizer and hen manure affect the eutrophication. The emissions of NMVOC and carbon dioxide to air, as well as phosphorus to waste water, are the major environmental concerns in the final egg phospholipids manufacturing. Other impact categories such as climate change, photochemical oxidant formation, terrestrial acidification and fossil depletion have lower global impact.

    Five scenarios have been conducted in order to validate the results, and to provide Fresenius-Kabi with improvements. Lowering the production and intake of hen feed per kilogram eggs with six percent decrease the environmental impacts by 2 to 6 percent. Changing the ethanol feedstock to cellulose-based feedstocks clearly diminishes the toxicity related emissions due to lower fertilizer and pesticide usage. To replace other fat and protein sources with the egg residue byproduct that is yielded within the life cycle is the best treatment method of the egg’s non-phospholipids content. No specific improvements to the treatment method of the hen manure have been found. The fifth scenario includes a sensitivity analysis on the egg yolk powder allocation factor. To increase it from 11 to 25 percent does not give any significant effect on the final results, since this life cycle phase already has very low environmental impact.

    Actions that will have a significant effect on the egg phospholipids’ total environmental impact are optimize fertilizer and pesticide usage at hen feed and ethanol feedstock cultivations, lower ammonia and phosphate emissions from the hen manure management, and finally, reduced solvent, carbon dioxide, phosphorus and phosphate emissions from the final egg phospholipids manufacturing. Fresenius-Kabi is recommended to further look into these emission sources in order to decrease the egg phospholipids’ environmental impact.

  • 161. Berggren, C
    et al.
    Finnveden, Göran
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Miljöstrategisk analys (fms).
    Gullberg, Anders
    KTH, Skolan för datavetenskap och kommunikation (CSC), Centra, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centre for Sustainable Communications, CESC.
    Jacobsson, S
    Kågesson, P
    Biltillverkare bör vara öppna kring utsläppen2015Inngår i: Svenska dagbladet, ISSN 1101-2412Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 162.
    Berggren, Max
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    Aerodynamisk optimering av vindkraftverks rotorblad med en genetisk algoritm, BEM-teori, och XFOIL2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    This study presents a methodology that enables the annual average power of a wind turbine to be increased by automatically optimizing it’s airfoil, twist and chord dis- tribution. As a part of the study the software SiteOpt has been developed. This software connects the open source software XFOIL with the blade element momen- tum theory. XFOIL gives lift and drag coefficients which enable the blade element momentum theory to predict the power of a wind turbine at different wind and ro- tational speeds. An optimization algorithm of the type genetic algorithms is used to develop a new rotor blade. An academic benchmark case (Unsteady Aerodynamics Experiment Phase III) was selected as a starting point of the optimization because wind tunnel data was available for that campain. With the geometry developed by the genetic algoritm a theoretical increase of 15 % more power could be extracted. However, it has been shown that the model has shortcomings at high wind speeds where the predicted power does not match wind tunnel data. This is thought to be related to that the model assumes a completely rigid blade. In real world applica- tions a rotorblade will bend on higher wind speeds (about 8 m/s). It is therefore concluded that the model in its current form is flawed and that future work should aim to take these effects into account. However, a wind histogram for a specific loca- tion was used in order to calculate the annual average power for the wind turbine. The wind histogram used in this study to obtain the results has it’s wind speeds 81 % before 10 m/s where the model is acceptable. Therefore the results are largely to be considered accurate. 

  • 163.
    Berglund, Daniel
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Miljöstrategisk analys (fms).
    Life cycle assessment comparison of CIPP lining and traditional pipe replacement2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    During the so-called “Miljonprogrammet”, over a million homes were built in Stockholm. As the buildings mature, parts of the buildings reach their technical life times and it is time to renovate them. At a time when the environmental impact of humans is a hot topic, it is appropriate to take the environment into account when deciding upon which restoration method to use. The sewage pipes are one of the important building parts in need of repair. This can be achieved by for example traditional pipe replacement or Cure-In-Place-Pipes (CIPP-lining).The goal of this study is to investigate and compare the environmental impact of traditional pipe replacement versus the use of the relining method CIPP lining by conducting a comparative life cycle assessment (LCA). The methods differ in the way that traditional pipe replacement demolishes the outer layers of the bathrooms and remove the old pipes to replace with new and restore the surface layers while CIPP-lining renovates the pipes from the inside with the use of a flexible liner.The purpose of the study has been to clarify the differences in environmental impacts of the different methods in a clear and easily understood way and thereby also simplify the decision-making process of property owners in need of renovation.With aid of the guidelines in ISO standards 14040 and 14044 a correct methodology has been used to ensure that the level of this work will be as high as possible. In combination with the software SimaPro specifically developed to handle the creation of various forms of life cycle assessments and the ISO standards a complex system been analyzed in detail.The results of the study show that CIPP-lining generally cause less environmental impacts than the traditional pipe replacement method. The analysis of 14 selected impact categories show that CIPP lining is preferable in 13 categories and that the traditional pipe replacement is preferable in 1 category. The sensitivity analysis show that the results change drastically depending on how much of the materials and energy used to demolish and reconstruct the outer layers of the bathroom one chooses to allocate to the new sewer pipes.The results show that the CIPP-lining results are dependent on the consumables and the liner assembly processes while the energy usage of the production process does not have a large impact on the results. For the traditional pipe replacement the results show that the consumable process is clearly the biggest impact while the piping production inflicts the least impact on the result.

  • 164.
    Berglund, Daniel
    et al.
    Tyréns AB, Stockholm, 118 86, Sweden.
    Kharazmi, Parastou
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap.
    Miliutenko, S.
    Björk, Folke
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap.
    Malmqvist, Tove
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Comparative life-cycle assessment for renovation methods of waste water sewerage systems for apartment buildings2018Inngår i: Journal of Building Engineering, E-ISSN 2352-7102, Vol. 19, s. 98-108Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This comparative life-cycle assessment highlights three main alternatives for renovation of waste water sewerage: pipe replacement, cured- in- place pipe (CIPP) lining (also called sliplining) and renovation by coatings. The functional unit of this study is a six-story block house that was built in 1960 and has 29 apartments. The characterized results of environmental impacts display an advantage for CIPP-lining over pipe replacement in 14 of the 18 studied impact categories. Regarding those categories in which impacts were comparatively large, when looking at the average impact from a European citizen according to the ReCiPe methodology for life cycle inventory list, pipe replacement has greater impacts than CIPP-lining. In general, the impacts of pipe replacement are related to new tiles, expanded polyester cement, the screed, and the material for waterproofing, as well as the electricity needed for drying the structure. The CIPP-lining method displays higher impacts than pipe replacement in just four categories. These impacts are, to a large extent, caused by the use of consumables such as gloves and cotton cloths. From an LCA-perspective, the study shows that the CIPP and coatings relining methods have advantages over pipe replacement under the condition that the technical lifetime is the same for these methods. Still, the uncertainty of service life, as well as Bisphenol A (BPA) emissions, remain as issues of concern for further study. There are also other differences among the alternatives that ultimately influence a property owner's choice of method, such as costs, inconvenience for the residents, renewal of bathroom interiors, and the way in which the property owner values the alternative technologies.

  • 165.
    Bergstrand, Susanne
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    Bonnier, Thérèce
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    Norra Djurgårdsstaden som nollstad: En studie av miljöprojektets sista etapp och dess potential2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    All around the world more and more people move from rural areas to live in the cities. Because of this, the urban areas have become an important part in the debate about the effects on the environment and sustainability. In many countries word wide initiatives have been taken to build sustainable cities and eco cities, the Stockholm Royal Seaport is one example. The vision for the district is to become a world class sustainable city based on the three dimensions of sustainable development: social, economic and ecologic. The municipality of Stockholm has set requirements for the buildings’ energy usage, emissions and amount of waste generated during the building process. These requirements are dynamic and will become stricter for every phase. To fulfill the requirements new innovations and technologies are being developed, among other solutions to change how people live in order to

    become a sustainable city.

    This paper examines if it is possible for the last phase, Loudden, of Stockholm Royal Seaport to become a city of zero-net energy buildings, zero carbon and zero waste, and what it would take to achieve this. The results show that from a technical perspective, and with the delimitations of this study, it would be possible for Loudden to become completely self-sufficient on solar energy, but not to become a city of zero carbon and zero waste. 

  • 166.
    Bergström, Ida Gomez
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    Bahr, Maximilian von
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    Konventionell sprängning eller fullortsborrning som tunneldrivningsmetod?2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    I denna rapport har de två vanligaste tunneldrivningsmetoderna konventionell sprängning och fullortsborrning, TBM undersökts. Konventionell sprängning innebär att små borrhål görs i berget där sprängmedel förs in för att sedan spränga bort materialet. Fullortsborrning innebär å andra sidan att en enda stor borr används vilket gör att tunnelhålet får samma dimension som själva borren. Målen med detta arbete var att ta reda på vilka faktorer som påverkar valet mellan dessa två metoder i Stockholm, att göra en jämförelse mellan metoderna ur ekologisk- och ekonomisk hållbarhetssynpunkt samt att undersöka hur hanteringen och användningen av

    det uttagna bergmaterialet för respektive metod ser ut. Med hjälp av kvalitativa intervjuer med tio personer inom tunnelbyggnadsbranschen har dessa mål besvarats. De resultat som framkommit visar att det finns ett flertal faktorer som påverkar valet, några mer än andra. De tyngst vägande är de ekonomiska och erfarenhetsmässiga faktorerna som talar till fördel för konventionell sprängning. Fullortsborrning har dock funnits vara den fördelaktiga metoden ur ett hållbarhetsperspektiv, främst eftersom den ger en mindre påverkan på den omgivande miljön. Hanteringen och användningen av det uttagna bergmaterialet har däremot visat att konventionell sprängning kan vara fördelaktigt eftersom det idag finns en etablerad industri kring just sprängt bergmaterial. Fullortsborrat material är idag inte efterfrågat på grund av dess dåliga kvalitet.

  • 167. Berndes, Göran
    et al.
    Cederberg, Christel
    Finnveden, Göran
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Persson, Linn
    Persson, Martin
    Sterner, Thomas
    Världshandeln har varit förödande för miljön på många ställen.2018Inngår i: Dagens NyheterArtikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 168. Bhattacharjee, S.
    et al.
    Saha, B.
    Uddin, M. S.
    Panna, C. H.
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Saha, R.
    Groundwater governance in Bangladesh: Established practices and recent trends2019Inngår i: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 8, s. 69-81Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Legal framework is very crucial to protect the vital resources, to provide rights to public and administration, to support national policy and to bring technological intervention to ensure equitable distribution, fair management, and effective decision making. In Bangladesh, groundwater is not directly priced (other than pumping costs), perhaps such issue is not surprising that users do not meter the volumes of water usage. Beside the industry, agricultural sector is by far the biggest groundwater consumer of this country, contributing significant amount of annual meter drop in the groundwater table to the annual decline of groundwater table. Additionally, the groundwater resources are severely affected by, pollution, encroachment and overexploitation. National Water Policy (1999) and Bangladesh Water Act (2013) are considered as country's pivotal legal framework but both of these lag behind to provide effective guidelines on permission, extraction limit, monitoring, protection of quality, water harvesting procedure, and recharge mechanism. Existing institutions suffer from consistent crisis, politics, corruption, absence of public participation and coordination of other institutions, mismanagement, and empirical assessment. This study evaluates the existing water related policies and functions of multidimensional institutions, and discusses the key challenges of effective groundwater management. The present paper also provides an overview of established practices around the world to cope with the common challenges.

  • 169.
    Bhattacharya, P.
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Hossain, M.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Jacks, G.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Matin Ahmed, K.
    Hasan, M. A.
    Von Brömssen, M.
    Frape, S. K.
    Hydrogeochemical contrasts across the multi-level aquifers of Bengal basin in Matlab, Bangladesh: Implications for arsenic free and low-manganese drinking water sources2016Inngår i: Arsenic Research and Global Sustainability - Proceedings of the 6th International Congress on Arsenic in the Environment, AS 2016, CRC Press/Balkema , 2016, s. 45-46Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Targeting shallow, intermediate-deep and deep aquifers, piezometers nests were installed at 15 locations in the Matlab region, an As hotspot in southeastern Bangladesh. Groundwater levels and water quality were monitored for over a three years period. Stable isotopic composition was used to identify the hydrogeological characteristics of different aquifers, hydraulic connectivity between the contaminated and safe aquifers. Within the shallow depth (up to 100m), two aquifers (Aquifer-1 and Aquifer-2) were identified, and groundwater from Aquifer-1 indicated consistently high As concentration was found to be As-enriched (median As levels upto 714 μg/L). Considerable variability in As concentrations were observed in Aquifer-2 wells (6–30 μg/L) comprising relatively oxidized or less reduced red and off-white sands. The intermediate-deep and deep aquifers were found to contain very low As concentration and these aquifers are hydraulically separated from the shallow aquifers. Groundwater depth and elevation and stable isotope signatures also reflect that intermediate-deep and deep aquifers, in most places belong to the same hydrostratigraphic unit (Aquifer-3). © 2016 Taylor & Francis Group, London.

  • 170.
    Bhattacharya, Prosun
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Bundschuh, J
    Groundwater for sustainable development - cross cutting the UN sustainable development goals2015Inngår i: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 1, nr 1-2, s. 155-157Artikkel i tidsskrift (Fagfellevurdert)
  • 171.
    Bhattacharya, Prosun
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Hossain, Mohammed
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Jacks, Gunnar
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Ahmed, K. M.
    Hasan, M. A.
    Von Brömssen, M.
    Groundwater arsenic pollution: A conceptual framework for sustainable mitigation strategy2014Inngår i: One Century of the Discovery of Arsenicosis in Latin America (1914-2014): As 2014 - Proceedings of the 5th International Congress on Arsenic in the Environment, CRC Press, 2014, s. 881-885Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Tubewells installed by local drillers, provide access of drinking water in rural Bangladesh. Significant proportion of these wells contains arsenic (As) above the WHO guideline and the Bangladesh Drinking Water Standard. Various attempts for mitigation at household and community scale have resulted in limited success, but through the local driller's initiatives, the tubewells are the source of priority drinking water supply. We have developed a concept of Sustainable Arsenic Mitigation (SASMIT) to identify and target the safe aquifers through detailed hydrogeological studies for scientific validation of the water quality with respect to the color of the shallow sediments as perceived by local drillers. Together with water quality monitoring, we have also targeted the Intermediate Depth Aquifers (IDA) for providing As-safe and low manganese (Mn) water. SASMIT intervention logic also considered the relevant socio-economic scenario, such as household distribution, poverty issues and available safe water access for prioritizing safe well installation.

  • 172.
    Bhattacharya, Prosun
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Vatten- och miljöteknik.
    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 India2011Inngår i: Encyclopedia of Environmental Health, Elsevier Inc. , 2011, s. 150-164Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 173.
    Bhattacharya, Prosun
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Mukherjee, A.
    Mukherjee, A. B.
    Groundwater Arsenic in India: Source, Distribution, Effects and Alternate Safe Drinking Water Sources2013Inngår i: Reference Module in Earth Systems and Environmental Sciences, Elsevier, 2013Kapittel i bok, del av antologi (Annet vitenskapelig)
    Abstract [en]

    Elevated natural groundwater arsenic, a carcinogen, has created a severe environmental health crisis in several parts of India. Since the discovery of groundwater arsenic and arsenicosis in West Bengal, in 1984, a huge wealth of information has been generated by groundwater arsenic research during the last three decades. The principal mechanism of arsenic mobilization in groundwater is believed to be reductive dissolution of Fe-oxyhydroxides in aquifer sediments. Arsenic enriched groundwater used for irrigation also leads to long-term risks for arsenic enrichment in the soils and bioaccumulation in crops. Various studies are ongoing to develop a holistic approach for arsenic mitigation.

  • 174.
    Bhattacharya, Prosun
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Naidu, Ravi
    Polya, David A.
    Mukherjee, Abhijit
    Bundschuh, Jochen
    Charlet, Laurent
    Arsenic in hydrological processes-Sources, speciation, bioavailability and management2014Inngår i: Journal of Hydrology, ISSN 0022-1694, E-ISSN 1879-2707, Vol. 518, s. 279-283Artikkel i tidsskrift (Annet vitenskapelig)
  • 175.
    Bhattacharya, Prosun
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Thunvik, Roger
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Jacks, Gunnar
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik. International Groundwater Arsenic Research Group.
    von Brömssen, Mattias
    Department of Soil and Water Environment Ramböll Sweden AB.
    Targeting Arsenic-Safe Aquifers in Regions with High Arsenic Groundwater and its Worldwide Implications (TASA)2015Rapport (Annet vitenskapelig)
  • 176.
    Bhattacharya, Prosun
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Vahter, M.
    Jarsjö, J.
    Kumpiene, J.
    Ahmad, A.
    Sparrenbom, C.
    Jacks, Gunnar
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Donselaar, M. E.
    Bundschuh, J.
    Naidu, R.
    Editors’ foreword2016Inngår i: 6th International Congress on Arsenic in the Environment, AS 2016, s. xlv-xlviArtikkel i tidsskrift (Fagfellevurdert)
  • 177. Bhowmick, S.
    et al.
    Halder, D.
    Chatterjee, D.
    Nriagu, J.
    Guha Mazumder, D. N.
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Iglesias, M.
    Saliva as a biomarker of arsenic exposure2014Inngår i: One Century of the Discovery of Arsenicosis in Latin America (1914-2014): As 2014 - Proceedings of the 5th International Congress on Arsenic in the Environment, CRC Press, 2014, s. 540-542Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Saliva is a biofluid that has not been used extensively as a biomonitoring tool in epidemiological studies. This study presents the arsenic (As) concentrations in saliva samples collected from populations of West Bengal, India. We found a significant (p &lt; 0.05) association between the Log transformed Daily Ingestion of As (μg day-1) and the As concentration in saliva (r = 0.68). Additionally, As concentration of saliva and urine also had a significant positive correlation (r = 0.60, p &lt; 0.05). Male participants, smokers and cases of skin lesion were independently and significantly associated with increase in salivary As. Thus our findings show that saliva is a useful biomarker of As exposure in the study population.

  • 178. Bhowmick, S.
    et al.
    Nath, B.
    Halder, Dipti
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Biswas, Ashis
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Majumder, S.
    Mondal, P.
    Chakraborty, S.
    Nriagu, J.
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Iglesias, M.
    Roman-Ross, G.
    Guha Mazumder, D.
    Bundschuh, J.
    Chatterjee, D.
    Arsenic mobilization in the aquifers of three physiographic settings of West Bengal, India: Understanding geogenic and anthropogenic influences2013Inngår i: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 262, s. 915-923Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

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

  • 179. Bhowmick, Subhamoy
    et al.
    Halder, Dipti
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Nriagu, Jerome
    Mazumder, Debendra Nath Guha
    Roman-Ross, Gabriela
    Chatterjee, Debashis
    Iglesias, Monica
    Speciation of Arsenic in Saliva Samples from a Population of West Bengal, India2014Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 48, nr 12, s. 6973-6980Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Saliva, an easily accessible biofluid, is validated as biomarker of arsenic (As) exposure in several villages of West Bengal, India. Pentavalent arsenic [As(V)] was found to be the predominant species in saliva, with the amount of inorganic As [As(V) and trivalent form, As(III)] being more than half of the total As in the samples. Significant association was found between total daily ingestion of As and As(V) (r = 0.59; p = 0.000), As(III) (r = 0.60; p = 0.000), dimethylarsinous acid (DMA(V)) (r = 0.40; p = 0.000), and monomethylarsonous acid (MMA(V)) (r = 0.44; p = 0.000), implying that these species have mainly been derived from the methylation of the inorganic As in the water that study participants drank and the food they ate. Analysis of confounding effects of age, sex, smoking, body mass index and the prevalence of skin lesion suggests that women and controls with no skin lesion had a higher capacity to methylate the ingested As compared to the rest of the population. Thus, our study demonstrates that As species in saliva can be an useful tool to predict the individual susceptibility where higher As exposure and a lower methylation capacity are implicated in the development of As-induced health effects.

  • 180.
    Bianchi, Adam
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Nylander, Gabriel
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Operation and Control of HVDC Grids2018Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Meshed high-voltage direct current grids are becoming an increasingly important technology for integrating renewable energies into the power system. To control the grids in the best possible way, optimal converter and grid control strategies are needed. This project studies how a four-terminal high-voltage direct current grid is operated and controlled by implementing different grid and converter control strategies. The grid control strategies examined are centralized voltage control and distributed voltage control with and without deadband. Simulations are made in the software PSCAD. Different fault types on the grid are studied to investigate how the power flow and voltage level are affected. An optimal value for both the deadband width and droop constant has been identified. Moreover, the results indicate that centralized droop control is not a suitable grid control strategy, whereas distributed voltage control with and without deadband are. The fault study indicates no differences between distributed voltage control with and without deadband. The power flow and voltage levels are identical for all fault types.

  • 181.
    Billstein, Tova
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Värnqvist, Sara
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Dagvattenåtervinning i byggnader: Analys av effektivitet, kostnad och miljöcertifiering i system inom Norden2019Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    I samband med kommande klimatförändringar kommer antalet skyfall och perioder av torka att öka i världen vilket i sin tur ställer större krav på städers dagvattenhantering. Ett sätt att förbättra dagvattenhanteringen är att införa vattenåteranvändning i byggnader. Syftet med detta arbete är därför att utreda olika referensobjekt inom Norden som planerar att införa denna sorts teknik, eller som redan etablerat tekniken på marknaden. Arbetet ämnar även att utforska olika driftrelaterade frågor samt utreda vilken teknik som är mest lönsam utifrån faktorerna effektiv återvinning av dagvatten, projektkostnad samt poänggivande möjligheter inom olika miljöcertifieringssystem.

    För att besvara de formulerade frågeställningarna utfördes fem intervjuer baserat på en semistrukturerad intervjuteknik med individer insatta i de olika referensobjekten. Därutöver granskades ett flertal dokument som införskaffats från de olika företagen, både från intervjuobjekten men även från andra inblandade. En modell i programmeringsprogrammet MATLAB togs fram för att beräkna antalet dagar då det insamlade dagvattnet täcker behovet i byggnaderna övriga beräkningar gjordes i Excel där data inhämtats från SMHI:s hemsida över historisk data.

    Efter vidare undersökning framkom det att det inom Norden finns fem aktuella projekt varav ett är i projekteringsfasen, ett i byggnadsfasen och tre är i drift. Sergelhuset i Stockholm är det största projektet sett till takyta. Huset försörjer systemet flest antal dagar av året med tillräckligt dagvattenmängd för att täcka upp det dagliga vattenbehovet i byggnaden. Citypassagen i Örebro bedömdes vara minst kostnadseffektivt då projektet hade högst kostnader samtidigt som byggnaden hade minst antal dagvattenförsörjningsdagar. Då information saknas för Skanskas huvudkontor och Humlehuset kunde dessa referensobjekt inte jämföras på likartat sätt.

    Det framkom även att det vanligaste förekommande miljöcertifieringssystemet var LEED som tillämpats inom både Sergelhuset, Celsius och Skanskas huvudkontor. Samtliga projekt har ambitioner om att nå den högsta nivån, platinum, främst på grund av kommersiella skäl. Citypassagen hade ansökt om Miljöbyggnad och beräknas att certifieras enligt näst högsta nivån - Silver.

  • 182.
    Bin Ashraf, Faisal
    et al.
    Univ Oulu, Water Resources & Environm Engn Res Unit, POB 4300, Oulu 90014, Finland..
    Haghighi, Ali Torabi
    Univ Oulu, Water Resources & Environm Engn Res Unit, POB 4300, Oulu 90014, Finland..
    Riml, Joakim
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Resurser, energi och infrastruktur.
    Alfredsen, Knut
    Norwegian Univ Sci & Technol NTNU Vassbygget, 442 Valgrinda, Trondheim, Norway..
    Koskela, Jarkko J.
    Finnish Environm Inst SYKE, Mechelininkatu 34a,POB 140, Helsinki 00260, Finland..
    Klove, Bjorn
    Univ Oulu, Water Resources & Environm Engn Res Unit, POB 4300, Oulu 90014, Finland..
    Marttila, Hannu
    Univ Oulu, Water Resources & Environm Engn Res Unit, POB 4300, Oulu 90014, Finland..
    Changes in short term river flow regulation and hydropeaking in Nordic rivers2018Inngår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, artikkel-id 17232Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Quantifying short-term changes in river flow is important in understanding the environmental impacts of hydropower generation. Energy markets can change rapidly and energy demand fluctuates at sub-daily scales, which may cause corresponding changes in regulated river flow (hydropeaking). Due to increasing use of renewable energy, in future hydropower will play a greater role as a load balancing power source. This may increase current hydropeaking levels in Nordic river systems, creating challenges in maintaining a healthy ecological status. This study examined driving forces for hydropeaking in Nordic rivers using extensive datasets from 150 sites with hourly time step river discharge data. It also investigated the influence of increased wind power production on hydropeaking. The data revealed that hydropeaking is at high levels in the Nordic rivers and have seen an increase over the last decade and especially over the past few years. These results indicate that increased building for renewable energy may increase hydropeaking in Nordic rivers.

  • 183. Birgisdottir, H.
    et al.
    Moncaster, A.
    Wiberg, A. Houlihan
    Chae, C.
    Yokoyama, K.
    Balouktsi, M.
    Seo, S.
    Oka, T.
    Luetzkendorf, T.
    Malmqvist, Tove
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Hållbarhet, utvärdering och styrning.
    IEA ESC annex 57 'evaluation of embodied energy and CO2eq for building construction'2017Inngår i: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 154, s. 72-80Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The current regulations to reduce energy consumption and greenhouse gas emissions (GHG) from buildings have focused on operational energy consumption. Thus legislation excludes measurement and reduction of the embodied energy and embodied GHG emissions over the building life cycle. Embodied impacts are a significant and growing proportion and it is increasingly recognised that the focus on reducing operational energy consumption needs to be accompanied by a parallel focus on reducing embodied impacts. Over the last six years the Annex 57 has 'addressed this issue, with researchers from 15 countries working together to develop a detailed understanding of the multiple calculation methods and the interpretation of their results. Based on an analysis of 80 case studies, Annex 57 showed various inconsistencies in current methodological approaches, which inhibit comparisons of results and difficult development of robust reduction strategies. Reinterpreting the studies through an understanding of the methodological differences enabled the cases to be used to demonstrate a number of important strategies for the reduction of embodied impacts. Annex 57 has also produced clear recommendations for uniform definitions and templates which improve the description of system boundaries, completeness of inventory and quality of data, and consequently the transparency of embodied impact assessments.

  • 184.
    Birkholzer, Jens T.
    et al.
    Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA..
    Tsang, Chin-Fu
    Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA.;Uppsala Univ, Uppsala, Sweden..
    Bond, Alexander E.
    Quintessa Ltd, Birchwood, England..
    Hudson, John A.
    Imperial Coll London, London, England..
    Jing, Lanru
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Stephansson, Ove
    GFZ Helmholtz Ctr Geosci, Potsdam, Germany..
    25 years of DECOVALEX - Scientific advances and lessons learned from an international research collaboration in coupled subsurface processes2019Inngår i: International Journal of Rock Mechanics And Mining Sciences, ISSN 1365-1609, E-ISSN 1873-4545, Vol. 122, artikkel-id UNSP 103995Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    This paper provides an overview of an international research collaboration for advancing the understanding and modeling of coupled thermo-hydro-mechanical-chemical (THMC) processes in geological systems. The creation of the international DECOVALEX Project, now running for over 25 years, was initially motivated by the recognition that prediction of these coupled effects is an essential part of the performance and safety assessment of geologic disposal systems for radioactive waste and spent nuclear fuel. Later it was realized that these processes also play a critical role in other subsurface engineering activities, such as storage of CO2, exploration of enhanced geothermal systems, and unconventional oil and gas production through hydraulic fracturing. Research teams from radioactive waste management organizations, national research institutes, regulatory agencies, universities, as well as industry and consulting groups have participated in the DECOVALEX Project, providing a wide range of perspectives and solutions to these complex problems. Analysis and comparative modeling of state-of-the-art field and laboratory experiments has been at the core of the collaborative work, with an increasing focus on characterizing uncertainty and blind prediction of experimental results. Over these 25 years, many of the major advances in this field of research have been made through DECOVALEX, as evidenced by three books, seven journal special issues, and a good number of seminal papers that have emerged from the DECOVALEX modeling work. Examples of specific research advances will be presented in this paper to illustrate the significant impact of DECOVALEX on the current state-of-the-art of understanding and modeling coupled THMC processes. These examples range from the modeling of large-scale in situ heater tests representing mock-ups of nuclear waste disposal tunnels, to studies of fluid flow and chemical-mechanical coupling in heterogeneous fractures, and to the numerical analysis of controlled-injection meso-scale fault slip experiments.

  • 185.
    Bisander, Iza
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Strategiska hållbarhetsstudier. Environmental strategies.
    Låga parkeringstal i utbyte mot grön mobilitet: erfarenheter från och jämförelse mellan kommuner i Sverige2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Denna studie har undersökt hur flexibla parkeringstal ser ut och motiveras i olika kommuner men har även undersökt ett specifikt fall där flexibla parkeringstal har tillämpats. Studien hade tre syften varav det första var att undersöka hur kommuner motiverar övergången till mer flexibla parkeringstal och det andra syftet var att undersöka hur kommunerna utformar principerna för flexibla parkeringstal för att tillmötesgå deras motiv. Det sista syftet var att analysera om mobilitetsåtgärder som införs i samband med flexibla parkeringstal påverkar de boendes resmönster och vardagsliv.

    För att besvara studiens syften användes kvalitativa forskningsmetoder. För att undersöka olika kommuners utformning och motivering av flexibla parkeringstal har en kvalitativ dokumentanalys genomförts. Alla kommuner använder inte flexibla parkeringstal utan det är ett relativt nytt fenomen. Denna studie identifierade 24 kommuner som tillåter flexibla parkeringstal i deras policydokument. När kommunernas parkeringspolicys jämfördes märkes en stor variation av utformningen av flexibla parkeringstal. Vissa kommuner har tydliga riktlinjer på vilka åtgärder som ger ett visst procentuellt avdrag medan andra kommuner lämnar det öppet för byggherren att utforma vilka åtgärder denne önskar göra utan förutbestämt avdrag.

    Området Fullriggaren i Malmö var ett av de första områdena som tillämpade flexibla parkeringstal. Området har varit bebott i cirka fem år och har inte utvärderats grundligt. Kvalitativa semi-strukturerade intervjuer utfördes med personer som bor i området Fullriggaren och det visade sig att de boende har influerats av mobilitetstjänsterna till en viss del men att deras resmönster också kan spåras till andra faktorer. Cykelinfrastrukturen, normer, attityder och närhet till service tros påverka respondenternas val av färdmedel.

  • 186.
    Biswas, Ashis
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Arsenic Geochemistry in the Alluvial Aquifers of West Bengal, India: Implications for targeting safe aquifers for sustainable drinking water supply2013Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The natural occurrences of high (>10 μg/L) dissolved arsenic (As) in groundwater of Bengal Basin has put millions of people under the threat of chronic As exposure through drinking water. Present study has examined the processes that regulate As mobilization and its distribution in shallow aquifers and the potentiality of finding safe aquifers within shallow depth (<50 m) for drinking water supply. The results indicate that in terms of aquifer sediment colors and water quality two types of aquifer namely brown sand aquifer (BSA) and grey sand aquifer (GSA) can be distinguished within the depth, accessible by low-cost drilling. The redox condition in the BSA is delineated to be Mn oxyhydroxides reducing, not sufficiently lowered for As mobilization resulting in high Mn and low Fe and As in groundwater. While in GSA, currently the reductive dissolution of Fe oxyhydroxides is the prevailing redox process causing As mobilization into groundwater of this aquifer type. It is revealed that the vertical distribution of As and other aqueous redox parameters is related to the redox zonation within aquifer. The decoupling of As and Fe release into groundwater is evident in the shallowest part of aquifer because of Fe enrichment by weathering of silicate minerals especially of biotite, the precipitation of secondary mineral phases like siderite and vivianite and incomplete reduction of Fe oxyhydroxides. It is characterized that the seasonal variations of As and other aqueous solutes are limited within the upper portion of aquifer only (<30 m bgl) and can be related to seasonal cycling of redox status, aggregation and dispersion of As scavenging colloids, local groundwater abstraction and monsoonal recharge. The results of surface complexation modeling indicate that PO43- is the major competitor of As(III) and As(V) adsorption onto Fe oxyhydroxides. This study concludes that the reductive dissolution of Fe oxyhydroxides followed by competitive sorption reactions with the aquifer sediment is the process conducive for As enrichment in groundwater of Bengal Basin. Present study advocates that despite low concentration of As in groundwater, a rigorous assessment of attendant health risk for Mn is necessary prior to considering mass scale exploitation of the BSA for sustainable drinking water supply. This study also validates that TW platform colors can be used as a rapid screening tool for As and Mn in drinking water wells to prioritize As mitigation management.

  • 187.
    Biswas, Ashis
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Mukherjee, Abhijit
    Nath, Bibhash
    Alexanderson, Helena
    Kundu, Amit K.
    Chatterjee, Debashis
    Jacks, Gunnar
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Delineation of shallow hydrostratigraphy in arsenic affected region of Bengal Basin: implication for targeting safe aquifers for drinking water supplyManuskript (preprint) (Annet vitenskapelig)
  • 188.
    Biswas, Ashis
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Mukherjee, Abhijit
    Nath, Bibhash
    Alexanderson, Helena
    Kundu, Amit K.
    Chatterjee, Debashis
    Jacks, Gunnar
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Shallow hydrostratigraphy in an arsenic affected region of Bengal Basin: Implication for targeting safe aquifers for drinking water supply2014Inngår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 485, s. 12-22Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To delineate arsenic (As) safe aquifer(s) within shallow depth, the present study has investigated the shallow hydrostratigraphic framework over an area of 100 km(2) at Chakdaha Block of Nadia District, West Bengal. Drilling of 29 boreholes and subsequent hydrostratigraphic modeling has identified three types of aquifer within 50 m below ground level (bgl). Aquifer-1 represents a thick paleochannel sequence, deposited parallel to the River Hooghly and Ichamati. Aquifer-2 is formed locally within the overbank deposits in the central floodplain area and its vertical extension is strictly limited to 25 m bgl. Aquifer-3 is distributed underneath the overbank deposits and represents an interfluvial aquifer of the area. Aquifer-3 is of Pleistocene age (similar to 70 ka), while aquifer-1 and 2 represent the Holocene deposits (age <951 ka), indicating that there was a major hiatus in the sediment deposition after depositing the aquifer-3. Over the area, aquifer-3 is markedly separated from the overlying Holocene deposits by successive upward sequences of brown and olive to pale blue impervious clay layers. The groundwater quality is very much similar in aquifer-1 and 2, where the concentration of As and Fe very commonly exceeds 10 mu g/L and 5 mg/L, respectively. Based on similar sediment color, these two aquifers have jointly been designated as the gray sand aquifer (GSA), which constitutes 40% (1.84 x 10(9) m(3)) of the total drilled volume (4.65 x 10(9) m(3)). In aquifer-3, the concentration of As and Fe is very low, mostly <2 mu g/L and 1 mg/L, respectively. This aquifer has been designated as the brown sand aquifer (BSA) according to color of the aquifer materials and represents 10% (4.8 x 10(8) m(3)) of the total drilled volume. This study further documents that though the concentration of As is very low at BSA, the concentration of Mn often exceeds the drinking water guidelines.

  • 189.
    Biswas, Ashis
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Gustafsson, Jon Petter
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Neidhardt, H.
    Karlsruhe Institute of Technology, Germany.
    Halder, Dipti
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Kundu, A.K.
    University of Kalyani, India.
    Chatterjee, Debashis
    University of Kalyani, India.
    Berner, Z.
    Karlsruhe Institute of Technology, Germany.
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Surface complexation modeling of temporal variability of arsenic in groundwater: Estimating the role of competing ions in the mobilization processes2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This study investigates the relative roles of different competing ions on the mobilization of arsenic (As) by surface complexation modeling of As rich groundwater in the aquifer of Bengal Basin. Two sets of piezometers, installed at different depths of the shallow aquifer (<50 m), have been monitored for As and other relevant hydrogeochemical parameters over a period of 20 months. The potentiality of two different surface complexation models (SCM), developed for ferrihydrite and goethite has been explored to account for the observed temporal variation in As(III) and As(V) concentration in groundwater. The SCM for ferrihydrite appears as the better predictor for the observed variation in both As(III) and As(V) concentration. It is estimated that among the competing ions PO43- is the major competitor of As(III) and As(V) adsorption into Fe oxyhydroxide and competing ability of the ions decreases as PO43- >> Fe(II) > H4SiO4 = HCO3-. The result of sensitivity test indicates that the competition of PO43- with As for the adsorption sites might already reach nearly to the stage of maxima. It is also shown that a slight increase or decrease in pH can have overwhelming effect on the mobility of As(III) and As(V) by changing their concentration oppositely. It appears that only the reductive dissolution of Fe oxyhydroxide cannot explain the observed high As concentration in the groundwater of Bengal Basin. In absence of potential competition for the adsorption sites, As released due to reductive dissolution of Fe oxyhydroxide would have been re-adsorbed into the residual Fe phases. This study suggests that the reductive dissolution of Fe oxyhydroxide followed by competitive ion exchange with the aquifer sediment is the processes conducive for As enrichment in groundwater of the sedimentary aquifers.

  • 190.
    Biswas, Ashis
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Gustafsson, Jon Petter
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Neidhardt, Harald
    Halder, Dipti
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Kundu, Amit K.
    Chatterjee, Debashis
    Berner, Zsolt
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Role of competing ions in the mobilization of arsenic in groundwater of Bengal Basin: Insight from surface complexation modeling2014Inngår i: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 55, s. 30-39Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study assesses the role of competing ions in the mobilization of arsenic (As) by surface complexation modeling of the temporal variability of As in groundwater. The potential use of two different surface complexation models (SCMs), developed for ferrihydrite and goethite, has been explored to account for the temporal variation of As(III) and As(V) concentration, monitored in shallow groundwater of Bengal Basin over a period of 20 months. The SCM for ferrihydrite appears as the better predictor of the observed variation in both As(III) and As(V) concentrations in the study sites. It is estimated that among the competing ions, PO43- is the major competitor of As(III) and As(V) adsorption onto Fe oxyhydroxide, and the competition ability decreases in the order PO43- >> Fe(II) > H4SiO4 = HCO- (3.) It is further revealed that a small change in pH can also have a significant effect on the mobility of As(III) and As(V) in the aquifers. A decrease in pH increases the concentration of As(III), whereas it decreases the As(V) concentration and vice versa. The present study suggests that the reductive dissolution of Fe oxyhydroxide alone cannot explain the observed high As concentration in groundwater of the Bengal Basin. This study supports the view that the reductive dissolution of Fe oxyhydroxide followed by competitive sorption reactions with the aquifer sediment is the processes responsible for As enrichment in groundwater.

  • 191.
    Biswas, Ashis
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Gustafsson, Jon Petter
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Neidhardt, Harald
    Halder, Dipti
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Kundu, Amit K.
    Chatterjee, Debashis
    Berner, Zsolt
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Role of competing ions on the mobilization of arsenic in groundwater of sedimentary aquifers: insight from surface complexation modelingManuskript (preprint) (Annet vitenskapelig)
  • 192.
    Biswas, Ashis
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik. University of Kalyani.
    Gustafsson, Jon Petter
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik. Swedish University of Agricultural Sciences.
    Neidhardt, Harald
    Karlsruhe Institute of Technology, Germany.
    Halder, Dipti
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik. University of Kalyani.
    Kundu, Amit Kumar
    University of Kalyani, India.
    Chatterjee, Debashis
    University of Kalyani, India.
    Berner, Zsolt
    Karlsruhe Institute of Technology, Germany.
    Bhattacharya, Prosun
    University of Kalyani.
    Estimating the role of competing ions on the arsenic mobilization processes in the aquifers of Bengal Basin by surface complexation modeling2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This study investigates the relative roles of the different competing ions on the arsenic (As) mobilization in the sedimentary aquifers of Bengal basin by surface complexation modeling of the temporal varaibility of As in shallow (<50 m) groundwater. Two sets of piezometers (2×5 = 10), installed at the two sites with relatively contrasting dissolved As concentration in groundwater, were monitored bi-weekly for As and other hydrogeochemical parameters over a period of 20 months. The estimation of the standard deviation (SD) for As(III) reflects strong temporal variation (SD ≥10 μg/L) in all the piezometers of two sites over the monitoring period. Particularly, the variation is more prominent in the shallowest part of the aquifer, where the site specific cyclic trends are evident. While, As(V) shows significant temporal variation in the piezometers of high As site only and no specific trend is reflected in the variation.

    Two different surface complexation models (SCMs), developed for ferrihydrite and goethite have been explored to account for the observed temporal variation in As(III) and As(V) concentrations. The SCM for ferrihydrite has provided the better estimation for both As(III) and As(V) variations.

    Among the different competing ions, PO43- appears as the major competitor of As(III) and As(V) adsorption onto ferrihydrite and the competition ability decreases in the order PO43- >> Fe(II) > H4SiO4 = HCO3-. It is further revealed that a small decrease in pH significantly increases the concentration of As(III) and decreases the As(V) concentration and vice versa. The present study suggests that the reductive dissolution of Fe oxyhydroxides alone cannot explain the observed high As concentration in groundwater of the sedimentary aquifers. Perhaps, the reductive dissolution of Fe oxyhydroxides followed by competitive sorption reactions with the aquifer sediment is the processes conducive for As enrichment in the groundwater of Bengal basin.

  • 193.
    Biswas, Ashis
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Neidhardt, Harald
    Kundu, Amit K.
    Halder, Dipti
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Chatterjee, Debashis
    Berner, Zsolt
    Jacks, Gunnar
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Spatial, vertical and temporal variation of arsenic in the shallo aquifers of Bengal Basin: Controlling geochemical processesManuskript (preprint) (Annet vitenskapelig)
  • 194.
    Biswas, Ashis
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik. University of Kalyani, India .
    Neidhardt, Harald
    Kundu, Amit K.
    Halder, Dipti
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik. University of Kalyani, India .
    Chatterjee, Debashis
    Berner, Zsolt
    Jacks, Gunnar
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Spatial, vertical and temporal variation of arsenic in shallow aquifers of the Bengal Basin: Controlling geochemical processes2014Inngår i: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 387, s. 157-169Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A detailed understanding of the geochemical processes that regulate the spatial, temporal and vertical variation of dissolved arsenic (As) in shallow aquifers (<50 m) is a prerequisite for sustainable drinking water management in the Bengal Basin. The present study conducted at Chakdaha Block of the Nadia District, West Bengal, India, combined a high resolution hydrogeochemical monitoring study over 20 months from two sets of piezometers (2 x 5) to the sediment geochemistry at areas with high (average:146 mu g/L, n = 5) and relatively low (average: 53.3 mu g/L, n = 10) dissolved As concentrations in groundwater. The determination of the isotopic composition of delta H-2 and delta O-18 in groundwater of the two sites indicated the recharge of evaporative surface water to the aquifer. The concentrations of major aqueous solutes (Ca2+, Mg2+, Na+, K+, HCO3- and Cl-) and electrical conductivity were considerably higher in wells at the high As site compared to the low As site. Additionally, at the high As site, the major ions, Fe, SO42-, electrical conductivity, delta H-2 and delta O-18 showed markedly greater enrichment in the shallowest part (<24 m) of the aquifer compared to the deeper part, reflecting vertical layering of groundwater composition within the aquifer. The oxidation of pyrites has been attributed to the high rate of mineral dissolution resulting in such greater enrichments in this part of the aquifer. In addition, the anthropogenic input with recharge water possibly increased the concentrations of Cl- in this part of the aquifer. The vertical layering of groundwater was absent in the aquifer at the low As site. The absence of such layering and relatively low major ion concentrations and electrical conductivity could be linked to the enhanced aquifer flushing and decreased water-ediment interactions influenced by local-scale groundwater abstraction. The seasonal variations of As concentrations in groundwater were observed only in the shallowest part of the aquifers (<30 m). Furthermore, the As concentrations in groundwater at the uppermost part of the shallow aquifers (<21 m) increased continuously over the monitoring period at both sites. This study supports the view that the reductive dissolution of Fe oxyhydroxides coupled with competitive PO43- sorption reactions in the aquifer sediment enriches As in groundwater of the Bengal Basin. However, the additional Fe released by the weathering of silicate minerals, especially biotite, or the precipitation of Fe as secondary mineral phases such as siderite, vivianite and acid volatile sulfides may result in the decoupling of As and Fe enrichment in groundwater. The redox zonation within the aquifer possibly regulates the vertical distribution of As in the groundwater.

  • 195.
    Bitow Meles, Desbele
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Review of Methods of Wastewater Reuse to Diminish Non-Biodegradable Organic Compounds.2014Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Wastewater reuse is very important in water resource management for both environmental and economic reasons. Unfortunately, wastewater from textile industries is difficult to treat by convectional wastewater treatment technologies. Now days, polluted water due to color from textile dyeing and finishing industries is burning issue for researchers. Textile or industrial wastewaters contain non-biodegradable organic compounds, which cannot be easily biodegraded because of their complex chemical structure. Dye wastewater discharged from textile wastewaters is one example of non-biodegradable organic compounds and it is difficult to remove dye effluent by convectional wastewater treatment methods. Therefore, this thesis deals about a review of advanced treatment technologies, which can de-colorize and remove non-biodegradable organic compounds from textile wastewater effluents. In addition to this, the potential and limitation of these advanced treatment methods are reviewed. Advanced treatment technologies reviewed in this paper are; Adsorption process, Membrane bioreactor (MBR) and advanced oxidation process (AOPs).

  • 196.
    Björk, Erik
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    Åkerberg, Viktor
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    Data Acquisition Architecture for HVDC Grids2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    The climate crisis has caused many countries around the world to invest in large amounts of renewable energy. To be able to handle the intrinsic unreliability and geographic de- pendency of many renewable energy sources, HVDC technology is considered due to its low cost when transferring electricity across great distances. Traditional AC grids are controlled with 15-minute intervals at control centers, but HVDC grids require a faster control due to more power fluctuations within the grid. The aim of this project was to propose an architecture for a gateway in a control center for an HVDC grid. The gateway was programmed in C and C++ and the data was sent using UDP packets. Testing of the gateway was done using a real-time simulation of an HVDC grid. The data was sent with intervals smaller than a second which satisfied the speed requirements for this project. A gateway like the one developed in this project can be implemented at control centers to display and process data and to improve the overall reliability of an HVDC grid. 

  • 197.
    Björk, Folke
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Byggnadsteknik.
    Olofsson, Bo
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Vatten- och miljöteknik.
    Sederholm, Bror
    Trägårdh, Jan
    RISE Cement- och betonginstitutet.
    Dränering av fukt i betong genom elektrokemisk metodik (elektroosmos) 2018Rapport (Annet vitenskapelig)
    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.

  • 198.
    Björklund, Erik
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    Hansson, Linus
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    VÄRMEÅTERVINNING I ALBANO: Energieffektivisering i studentbostäder2013Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Rapporten beskriver undersökningen av två värmeåtervinningsmetoder, frånluftsvärmepump och frånlufts/tilluftsvärmeväxlingssystem (FTX-system), för en av Svenska Bostäders byggnader i det kommande byggprojektet i Albano. Syftet var att göra detta utifrån hållbarhetsaspekterna energieffektivitet, klimatpåverkan i form av växthusgasutsläpp samt driftskostnader för inköpt energi. Uppbyggnad av en värmeflödesmodell, baserad på en av byggnaderna i området, samt energiberäkningar för respektive uppvärmningssystem, visade att det relativt nollalternativ gick att spara 55 % av uppvärmningsbehovet om frånluftsvärmepumpen väljs och 45 % om FTX-systemet väljs. Totalt sett tyder resultaten på att frånluftsvärmepumpsystemet utgör ett något mer fördelaktigt alternativ, men om den studerade byggnadens totala klimatskalsprestanda kan uppnå mycket låga värmegenomgångstal utgör FTX-alternativet det bättre alternativet.

  • 199.
    Björling, Axel
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Hillesöy, Fredrik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Enkätundersökning om studenters resvanor på KTH: Vad kan göras för att främja cyklande på och till KTH Campus Valhallavägen?2018Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Abstract

    This report is a part of the project Pre-study on a proactive and integrative cycling strategy for KTH. A survey about the travel habits of KTH students to and from campus was done in collaboration with Nils Brown, employee at the SEED-institution at KTH. The results from the survey are presented in this report. The main focus is cycling, reasons for why students don’t ride a bike to campus, and what actions can be made to promote more students to use bicycles as their primary transport. The purpose of the project is to find out what actions can be taken for more students to ride a bicycle to campus. The results from the survey shows that public transport is the most common transport among students both during winter and summer. About 17 percent of the surveyed students ride a bicycle to campus during summer, while 6 percent do it during the winter. Further analysis of the answers from the survey have been made to find out if there’s any connection between the travel habits and the distance from where the students live to campus. Also, to find out if the habits have got any connection to where the students lived before commenced studies at KTH. An investigation has also been made about what different actors like Stockholms Stad, Akademiska Hus and Trafikverket are doing to encourage cycling. A short literature study has been made to gather complementary information about cycling. Some information has also been gathered from scientific articles about research on what actions have been taken to increase cycling in other cities. From the survey the conclusion that better options for showering/changing rooms on campus, better mindset towards cycling together with more and safer cycle paths to campus was made. The scientific articles used for the the report also explains that good infrastructure for cycling is important to encourage it, but it’s a combination of several different factors that makes cycling more appealing.

  • 200.
    Björn, Erik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    A circular production of fish and vegetables in Guatemala: An in-depth analysis of the nitrogen cycle in the Maya Chay aquaponic systems2018Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This study was done with the aim of deepening the understanding of the Maya Chay aquaponic systems. To meet the aim, a literature study on aquaponics, with an emphasis on the nitrogen metabolism in such systems, was conducted. Furthermore, a deep investigation of the specific Maya Chay systems was made to understand how these systems might be different from the general aquaponic designs. Finally, two nitrogen balances were developed with the purpose of examining the dynamics of the nitrogen transformations in two Maya Chay aquaponic systems. The measurements for the nitrogen balances was made between Mars 2017 to July 2017, and the model for the nitrogen balances evaluated the amount of nitrogen as:

    i) nitrogen input to the system through the feed,

    ii) nitrogen assimilated by the fish and the plants,

    iii) nitrogen accumulated in the sludge, and

    iv) nitrogen lost to the atmosphere through denitrification and similar processes such as anammox.

    The resulting nitrogen balances showed some interesting differences in the dynamics of nitrogen distribution. In the smaller Maya Chay XS system in Antigua, only 36 % of the nitrogen input was assimilated by the fish (30 %) and the plants (6 %) and 64 % of the nitrogen input could be regarded as lost, either to the atmosphere (46 %) or in the sludge (18 %). The other nitrogen balance showed that the distribution of nitrogen in the Maya Chay S system in Chinautla is much more efficient in taking care of the nitrogen input. In this system 70 % was assimilated by the fish (33 %) and the vegetables (37 %) and the remaining 30 % was lost, either to the atmosphere (14 %) or in the sludge (16 %).

    The nitrogen balances also showed that both systems are almost equally efficient in terms of nitrogen assimilation by the fish, and that the big differences lie in the rate of nitrogen assimilation by the plants (6 % vs. 30 %) and in the nitrogen loss to the atmosphere (46 % vs. 14 %). A likely explanation for these differences is the difference in design of the vegetable beds, where the less efficient system in Antigua has a large surface area for the vegetable bed, but only a small portion of this could be utilized for vegetable growth. Furthermore, a consequence of the larger surface is a larger anoxic zone in the bottom of the vegetable bed, which promotes the growth of denitrifying and anammox bacteria. These kinds of bacteria convert the dissolved ammonia, nitrite and nitrate to gas forms of nitrogen, such as nitrogen gas and nitrous oxide and thus nitrogen is lost from the system to the atmosphere.

    Finally, this study also showed a great difference in the ratio of vegetable to fish production between the systems, where the ratio was 0.43 in Antigua and 2.7 in Chinautla. This ratio further indicates the difference in design between the systems, especially regarding the vegetable beds, has an impact on how well they perform, both in terms in economic and productivity terms, but also in terms of the release of greenhouse gases (nitrous oxide). It can therefore be concluded that the original design of the Maya Chay system (i.e. the Chinautla system) is the preferable one.

    Even though the accuracy of the measurements in the experiments could be improved for future studies, this study has demonstrated the value of making nitrogen balances for aquaponic systems. Nitrogen balances increase the knowledge of the performance of the system and they increase the understanding of the dynamics of nitrogen transformations that takes place in the system. This knowledge can then be utilized to adjust the design and/or verify if either the aquaculture or hydroponic system is properly designed.

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