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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Sustainable Public Procurement : Development and analysis of tools for construction works

Verzat, Benoit January 2008 (has links)
Embedded in the economic competition, public procurement has amajor role to play in being a driving force for the promotion of a globallypositive competition that prides the best sustainable products and services,rather than only the more economically efficient ones. Responsible for ahuge part of the human pressure on natural resources, and having a largeshare in the public funding, the built environment sector provides animportant venue for the use of sustainable public procurement as a tool toenhance the sustainability of societies.Selecting the best sustainable offer is a challenging task requiringenvironmental and social assessments that can only be based on complexlife cycle thinking analysis. Through the development of the “ExhaustiveSustainable public procurement clauses Manual”, this paper analyses publicprocurement issues and their potential solutions, with a focus on theenvironmental performance in buildings procurement.
112

Technical Development of Waste Sector in Sweden: Survey and LifeCycle Environmental Assessment of Emerging Technologies

Uz Zaman, Atiq January 2009 (has links)
Waste can be considered as an urban burden or as a valuable resource depending on how it ismanaged. Different waste treatment technologies are available at present to manage municipal solidwaste (MSW). Various actors are involved to develop waste treatment technology for certain area.The aim of this study is to analyze the driving forces in technical development in waste sector inSweden. The study is also done to identify emerging waste management technology in Sweden.Moreover, a comparative study of existing and emerging technologies is done by Life CycleAssessment (LCA) model. An extensive literature review and pilot questionnaire survey among thewaste management professionals’ is done for the study. LCA model is developed by SimaProsoftware CML2 baseline method is used for identifying environmental burden from the wastetechnologies.Dry composting, Pyrolysis-Gasification (P-G), Plasma-Arc are identified as potential emergingtechnologies for waste management system in Sweden. Technical developments of thesetechnologies are influenced by indigenous people’s behavior, waste characteristics, regulations, healthor environmental impact and global climate change. Comparative LCA model of P-G andIncineration shows that, P-G is a favorable waste treatment technology than Incineration for MSW,especially in acidification, global warming and aquatic eco-toxicity impact categories.
113

Improvements of U-pipe Borehole Heat Exchangers

Acuña, José January 2010 (has links)
The sales of Ground Source Heat Pumps in Sweden and many other countries are having a rapid growth in the last decade. Today, there are approximately 360 000 systems installed in Sweden, with a growing rate of about 30 000 installations per year. The most common way to exchange heat with the bedrock in ground source heat pump applications is circulating a secondary fluid through a Borehole Heat Exchanger (BHE), a closed loop in a vertical borehole. The fluid transports the heat from the ground to a certain heating and/or cooling application. A fluid with one degree higher or lower temperature coming out from the borehole may represent a 2-3% change in the COP of a heat pump system. It is therefore of great relevance to design cost effective and easy to install borehole heat exchangers. U-pipe BHEs consisting of two equal cylindrical pipes connected together at the borehole bottom have dominated the market for several years in spite of their relatively poor thermal performance and, still, there exist many uncertainties about how to optimize them. Although more efficient BHEs have been discussed for many years, the introduction of new designs has been practically lacking. However, the interest for innovation within this field is increasing nowadays and more effective methods for injecting or extracting heat into/from the ground (better BHEs) with smaller temperature differences between the heat secondary fluid and the surrounding bedrock must be suggested for introduction into the market. This report presents the analysis of several groundwater filled borehole heat exchangers, including standard and alternative U-pipe configurations (e.g. with spacers, grooves), as well as two coaxial designs. The study embraces measurements of borehole deviation, ground water flow, undisturbed ground temperature profile, secondary fluid and groundwater temperature variations in time, theoretical analyses with a FEM software, Distributed Thermal Response Test (DTRT), and pressure drop. Significant attention is devoted to distributed temperature measurements using optic fiber cables along the BHEs during heat extraction and heat injection from and to the ground. / <p>QC 20100517</p> / EFFSYS2 / Efficient Use of Energy Wells for Heat Pumps
114

Bed filters for phosphorus removal in on-site wastewater treatment : Removal mechanisms and sustainability

Eveborn, David January 2010 (has links)
For many surface waters, phosphorus (P) leaching is a serious problem that should be minimized to prevent eutrophication. In Sweden there is a demand for physical and technical development of high-performance P removal techniques to reduce phosphorus leaching from on-site wastewater treatment systems to the Baltic Sea. However, although these systems are designed to reduce eutrophication there are also other environmental impacts to be considered when implementing them in on-site systems; energy use and global warming potential are two examples. This study has investigated several bed filter materials (reactive media and natural soils) for their total environmental impact (in commercial applications) as well as for the predominating chemical phosphorus removal mechanisms. The use of life cycle assessment revealed that several reactive bed filters are relatively energy-consuming due to the material manufacturing process. Characterization of phosphorus compounds in used reactive media provided evidence for calcium phosphate precipitation as the predominating P removal mechanism in alkaline filter materials. However, in soil treatment systems with noncalcareous soils, batch experiments and extractions suggested that aluminium compounds were important for P removal. According to mass balance calculations that compared accumulated P with the estimated P load in a soil treatment system, the long term P removal capacity was very low; only 6.4 % of the applied phosphorus had been removed during 16 years of operation. / <p>QC 20110413</p>
115

OPERATIONALIZING SUSTAINABLE DEVELOPMENT GOAL 11 : Utilization of a neighborhood sustainability assessment tool for localizing the sustainable development goals in Swedish municipalities

Boxner Åsbrink, Johannes January 2023 (has links)
Efforts towards sustainable urban areas are fundamental for the attainment of the Sustainable Development Goals [SDGs], embodied in goal 11 of sustainable cities and communities. Sustainable urban development requires the goals to be localized and operationalized to the applied areas needs and prerequisites. Localization and operationalization of the goals has, however, proved to be difficult in a local setting. In relation, Neighbourhood Sustainability Assessment [NSA] tools are found to provide directives, metrics and indicators of community sustainability assessments, possibly appliable to provide guidance for local governance to operationalize the SDGs. This degree project aims to evaluate the possibility of SDG.11 attainment and policy operationalization at a local level through the use of an established NSA-tool, BREEAM-C. To do so, this degree project use deductive thematic analysis, with SDG.11 targets as analytical framework, to evaluate connectivity to SDG.11 of local policy documents stated to direct efforts of SDG.11 implementation and the selected NSA-tool manual. Further, a composite index of NSA-tool indicators, ranked and adapted to local intentions, is developed through an analytical hierarchy process. Overall strong connections, though variable, to SDG.11 are found for both municipal and NSA-tool intentions of urban development as well as between municipal and NSA-tool intentions. The proposed composite index for SDG.11 implementation is deemed to adequately answer to municipal intentions of SDG.11 implementation.
116

Biodiversity in environmental assessment : tools for impact prediction

Gontier, Mikael January 2005 (has links)
Urbanisation and infrastructure developments impact on the surrounding natural environment and threaten biodiversity. The fragmentation of natural habitats in particular is a major obstacle for the preservation of biodiversity in a long-term perspective. In the planning process, both the environmental impact assessment and strategic environmental assessment processes play a central role in the identification and prediction of impacts on biodiversity. At the same time, the devel-opment of GIS technologies and GIS-based ecological models offer new perspectives in the elaboration of predictions. In order to analyse current practices and identify the need for im-provements in the environmental impact process, a review of environmental impact assessment reports was carried out. Further, a review of existing GIS methods and GIS-based ecological models is presented. The results of the review of environmental impact assessment reports show a lack of predictions in current biodiversity assessments. These asssessments often concentrate on impacts at the local scale, failing to consider large-scale and widespread impacts at the ecosys-tem and landscape levels. The review of GIS methods and GIS-based ecological models demon-strate the possibility to generate quantitative predictions for a specific area as well as for it’s sur-rounding environment. At the same time, the flexibility and reproducibility of such methods would allow predictions to be made for different alternatives or scenarios, therefore providing decision makers with relevant information of potential impacts on biodiversity. This would, in turn, result in an improved integration of biodiversity issues in physical planning and contribute to a sustainable development. / QC 20101129
117

Småskalig vattenkraft i Tyresån : En undersökning av ekologiska åtgärder utifrån de globala hållbarhetsmålen / Small scale hydro power in Tyresån : Evaluating ecological measures based on the sustainable development goals

Pirak Kuoljok, Simon, Wallin, Tony January 2019 (has links)
I Sverige finns det ungefär 2 100 vattenkraftverk som står för ca 40 % av Sveriges elproduktion.Ungefär 1 700 av dem är småskaliga vattenkraftverk och utgör 2,1 % av vattenkraftens elproduktion.Vattenkraften har negativa ekologiska konsekvenser på vattendragets konnektivitet vilket skaparproblem för den biologiska mångfalden. Tyresån vattensystem ligger i Stockholms län och är reglerat.Vattensystemet har tre vandringshinder, inklusive ett småskaligt vattenkraftverk – Uddby kvarn,vilket medför att vattensystemet har en dålig ekologisk status utifrån konnektivitet. Syftet medrapporten är att sammanställa de nyttor och problem som finns kopplade till den småskaligavattenkraften i Sverige och utifrån detta ta reda på vilka av FN:s globala hållbarhetsmål som påverkasav den småskaliga vattenkraftens verksamhet. För att undersöka det genomförs en litteraturstudiesamt en fallstudie, med inslag av intervjuer från sakkunniga informanter, som fokuserar på Tyresånsvattensystem. Platsbesök har även förekommit vid två tillfällen. De värden som är kopplade till småskalig vattenkraft är betydelsen för elsystemet, ekologiskaeffekter samt sociala och kulturella värden. I nedre Tyresån finns de tre strömmarnaFollbrinksströmmen, Nyfors och Uddby kvarn som alla är reglerade på olika sätt. Uddby kvarnlevererar el till ungefär 500 hushåll. Utifrån intervjuerna är närheten till höga naturvärden samt högakulturvärden positivt i Tyresån och bör behållas. Tyresåns ekologiska status utifrån konnektivitet ochfisk är dålig samt näringsämnen och bottenfaunan är måttlig. De åtgärder som tas upp för förbättradkonnektivitet är inlöp, anpassad reglering, återställning i Nyfors, biotopvård i Follbrinksströmmen,fingaller och uppsamling av ål. Sex globala hållbarhetsmål har tagits fram som går att koppla tillTyresåns vattensystem. Målkonflikter och synergier diskuteras, likaså ekologiska effekter kontra elproduktion och betydelsenav den småskaliga vattenkraften i Sverige. Den åtgärd som skulle gynna alla globala målen förTyresån är en återställning i Nyfors. Det finns även synergier mellan de globala målen rent vatten ochekologisk mångfald samt hållbar energi och bekämpa klimatförändringarna. Den störstamålkonflikten mellan de globala målen hållbar energi för alla och ekosystem och biologisk mångfald. / In Sweden, there are approximately 2 100 hydropower plants, which account for about 40 % ofSweden's electricity. Approximately 1 700 of them are small-scale hydropower plants and constitute2,1 % of the hydroelectric power generation. Hydroelectric power has negative ecologicalconsequences on the water's connectivity, which creates problems for biodiversity. Tyresån islocated in Stockholm County and is regulated. The water system has three migratory obstacles,including a small-scale hydropower plant - Uddby kvarn, which means that the water system has apoor ecological status based on connectivity. The aim of the report is to compile the benefits andproblems associated with the small-scale hydropower in Sweden and investigate which of the UN'ssustainable development goals that are affected by the small-scale hydropower. A literature study isconducted along with a case study which focus on Tyresån’s water system where two interviews andtwo site visits has been carried out. The values linked to small-scale hydropower are the importance for the electricity system, ecologicaleffects as well as social and cultural values. In the lower Tyresån there are the three streamsFollbrinksströmmen, Nyfors and Uddby kvarn which are all regulated in different ways. Uddby kvarnsupplies electricity to approximately 500 households. Based on the interviews, the proximity tonature and high cultural values are positive in Tyresån and should be sustained. Tyresån's ecologicalstatus is poor, due to lack of connectivity, fish, nutrients and bottom fauna. The actions suggested forimproved connectivity are inlets, custom regulation, restoration in Nyfors, biotope care inFollbrinksströmmen, grid and collection of eels. Six sustainable development goals can be linked tothe Tyresån water system. Conflicts and synergies are discussed. The main conflict is between ecological effects versuselectricity production and the importance of small-scale hydropower in Sweden. The action thatwould benefit all sustainable development goals for Tyresån is a restoration in Nyfors. There are alsosynergies between the sustainable development goals of clean water and sanitation and life on land,as well as affordable and clean energy and climate action. The largest conflict between thesustainable development goals related to small scale hydro power are affordable and clean energyand life on land.
118

Fosforsorptionskapaciteten i djupa jordlager : En kemisk analys av fosforadsorption i svenska grus- och sandjordar / Phosphorus sorption capacity in deep soils : A chemical analysis of phosphorus sorption in Swedish gravel and sand soils

Ekstrand, Charlotte, Hamberg, Camilla January 2019 (has links)
Det största hotet mot våra vattenmiljöer idag är eutrofieringen - överskottet av näringsämnen orsakat av avlopp och jordbruk. För att motverka detta krävs mer kunskap kring uppträdandet av fosfor i jord och, mer specifikt, fosforsorptionskapaciteten i sand- och grusjordar. Särskilt intressant är detta då enskilda avlopp (som är en stor källa till fosforutsläpp i Sverige) är uppbyggda av infiltrationsbäddar bestående av sand- och grusjordar. Syftet med denna rapport har varit att bestämma fosforsorptionskapaciteten i olika sand- eller grusbaserade jordar. Undersökningen har genomförts med hjälp av skakförsök och verktyg såsom MS Excel och Visual MINTEQ, och resultaten modellerades utifrån Freundlichekvationen. Även kemisk analysutrustning såsom ICP och AutoAnalyzer har använts för att analysera elementkoncentrationer i jordproverna. Resultaten visar att det finns ett positivt linjär-logaritmiskt samband mellan mängden adsorberat P och mängden tillsatt P i proverna. Det visade sig att de undersökta jordarna i snitt kunde binda 0.56 mmol fosfor/kg jord, eller 26.01 g fosfor per m3 jord. Vidare konstaterades även att mängden adsorberat P korrelerar linjärt med mängden oxalatlösligt Al och Fe i jordprovet. För majoriteten av jordproverna som uppvisade ett pH-värde högre än 8, verkade utfällningar av kalciumfosfater öka mängden bunden P. Då svenska mineraljordar med låg halt humusämnen oftast har ett pH-värde på 5.2-5.4, kan det argumenteras för att Al- och Fe-(hydr)oxider är av större betydelse för lösligheten av P än förekomsten av kalcium. Vidare undersökningar skulle kunna genomföras för att öka förståelsen för hur närvaron av humusämnen och jorddjupet påverkar fosforsorptionen, samt dess pH-beroende. / The eutrophication of our seas, lakes, and rivers is one of today's biggest threats to the aquatic environment. To counteract this, more knowledge concerning the behavior of phosphorus in soils and, more specifically, the efficiency of phosphate removal in sand and gravel soils is, greatly needed. This is particularly the case as most private wastewater systems (a considerable source of phosphorus leakage in Sweden) are based on infiltration beds consisting of sand and/or gravel soils. The objective of this research has been to determine the phosphorus sorption capacity of different sand or gravel-based soils. The study has been carried out using batch experiments and tools such as MS Excel and Visual MINTEQ, and the results were modeled according to the Freundlich equation. Chemical analysis equipment such as an ICP and AutoAnalyzer were also used to determine element concentrations in the soil samples. The results show that there is a positive linear logarithmic relationship between the amount of sorbed P and the amount of added P to the sample. It was concluded that the analyzed soils on average bound 0.56 mmol P per kg soil, or alternatively, 26.01 g P per m3 soil. Furthermore, it was found that the amount of sorbed P correlated linearly with the amount of oxalate-extractable Al and Fe in the soil sample. For most of the samples with a pH exceeding 8, precipitation of calcium-phosphates appeared to increase the amount of sorbed P. Since most Swedish mineral soils with a low organic content have a pH of 5.2-5.4, it can be argued that Al- and Fe-(hydr)oxides play a larger role in the adsorption of phosphorus than precipitation of calcium-phosphates. Further testing should be carried out to determine the pH-dependency, influence of soil depth, and influence of organic compounds on the phosphorus sorption capacity in sand- and gravel soils.
119

Enhancing Environmental Performance by Green Procurement : A study of environmental procurement preferences in the construction industry

Varnäs, Annika January 2008 (has links)
In recent years, the general awareness of the environmental impacts that industrial production gives rise to has radically increased throughout the world. Finding ways to minimise these impacts has become a major concern of the authorities in many countries. In order to promote a more sustainable industrial production, different incentives can be used. Among these incentives, the consideration of environmental issues in public procurement is increasingly being emphasised. While much attention regarding sustainable procurement has centred on the purchase of products, this thesis focuses on green procurement of construction contracts. The construction industry is a major contributor to environmental pollution. It consumes about half of all resources humans take from nature and accounts for about 25 – 40 per cent of all energy used and about 30 – 50 per cent of all waste generated in OECD countries. In the procurement of products, the environmental impacts of the available products can be estimated and compared, for example by using tools such as life cycle assessments. When construction contracts are procured, assessing the suppliers’ environmental capabilities can be more challenging, as the contract to be procured has not yet been performed. However, at the same time, there are considerably more opportunities to steer the construction towards more environmentally friendly alternatives. In the thesis, it is suggested that the environmental requirements and the environmental criteria for tender evaluation should be used in combination, in order to safeguard environmental performance in the construction project and at the same time stimulate a green development within the industrial sector. In addition, the role of the client in ensuring that the environmental requirements are fulfilled during construction work is emphasised. / QC 20101125
120

Exploring the circular economy of urban organic waste in sub-Saharan Africa: opportunities and challenges

Ddiba, Daniel January 2020 (has links)
Globally, there is increasing awareness of the importance of applying circular economy principles to the management of organic waste streams through resource recovery. In the urban areas of sub-Saharan Africa which are going to host a significant part of population growth over the next three decades, this is especially relevant. Circular economy approaches for sanitation and waste management can provide incentives to improve infrastructure and consequently contribute resources for water, energy and food that power urban livelihoods. This thesis is situated at the intersection of the circular economy on one hand and sanitation and waste management systems on the other. It aims to contribute to knowledge about the circular economy by investigating the potential contribution of resource-oriented urban sanitation and waste management towards the implementation of a circular economy in sub-Saharan Africa and the opportunities and challenges thereof. In pursuit of the above aim, the thesis employs a mixed methods approach and is operationalized in two case study locations: Kampala (Uganda) and Naivasha (Kenya). The findings reveal the quantities of resource recovery products like biogas, compost and black soldier fly larvae that can be obtained from the organic waste streams collected in a large city, demonstrate the viability of valorizing dried faecal sludge as a solid fuel for industrial applications, and identify the factors that facilitate or impede the governance capacity to implement circular economy approaches to the management of organic waste streams in urban areas in sub-Saharan Africa. The methods used for quantifying the potential for valorizing organic waste streams and for assessing governance capacity demonstrate approaches that could be applied in other urban contexts with interest in implementing circular economy principles. The discussion highlights some key implications of these findings for sanitation and waste management practices, arguing that it is time for a shift in sub-Saharan Africa from designing sanitation and waste management systems for disposal to designing them for resource recovery. / Globalt ökar medvetenheten om vikten av att tillämpa principer för cirkulär ekonomi för att hantera organiska avfallsströmmar genom resursåtervinning. I de urbana områdena i Subssahariska Afrika är detta särskilt relevant, då dessa förväntas stå för en betydande del av befolkningsökningen under de kommande tre decennierna. En mer cirkulärekonomi för sanitet och avfallshantering kan ge incitament för att förbättra infrastrukturen och därmed bidra med resurser till produktion av vatten, energi och mat som driver städernas försörjning. Denna licentiatuppsats befinner sig i skärningspunkten mellan cirkulär ekonomi å ena sidan och sanitets- och avfallshanteringssystem å andra sidan. Syftet är att bidra med kunskap om cirkulär ekonomi genom att undersöka potentialen för resursorienterad stadssanitet och avfallshantering att bidra till genomförandet av cirkulär ekonomi i Subsahariska Afrika, samt dess möjligheter och utmaningar. För att uppnå ovanstående syfte används flera olika metoder och genomförs i två fallstudiestäder: Kampala i Uganda respektive Naivasha i Kenya. Resultaten visar på de mängder av resursåtervinningsprodukter som biogas, kompost och svarta soldatflugelarver som kan erhållas från organiska avfallsströmmar som samlas in i en stor stad. Dessutom visar resultaten livskraftigheten för att valorisera torkat avföringsslam som ett fast bränsle för industriella tillämpningar. Slutligen identifierar resultaten faktorer som underlättar eller hindrar styrningskapaciteten för att genomföra cirkulär ekonomi-strategier för hantering av organiska avfallsströmmar i stadsområden i Subsahariska Afrika. Metoderna som används för att kvantifiera potentialen att valorisera organiska avfallsströmmar och  att utvärdera styrningskapacitet är metoder som kan tillämpas i andra urbana sammanhang där det finns intresse för att genomföra cirkulära ekonomiska principer. Diskussionen belyser några viktiga konsekvenser av dessa fynd för sanitets- och avfallshanteringspraxis och argumenterar för att det är dags för en övergång i SSA från att utforma sanitets- och avfallshanteringssystem för bortskaffande till att utforma dem för resursåtervinning. / <p>QC 20200513</p> / UrbanCircle: Urban Waste into Circular Economy Benefits

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