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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.
221

An evaluation of responsible tourism on livelihoods and natural resource management : a case study of Malealea, Lesotho

Moeketse, Libuseng Mary-Stella January 2006 (has links)
Includes bibliographical references (leaves 71-79). / The past two decades have seen numerous changes in ideas that inform the tourism industry. In part this is as a result of the introduction of principles of sustainability in tourism which endeavours to address key concerns in tourism including socio-economic inequity and environmental degradation. This dissertation seeks to understand these changes by evaluating the influence of responsible tourism on livelihoods and natural resource management. Malealea Lodge in Lesotho is used as a case study. The objectives of this study elucidate the influence of responsible tourism on livelihoods and naturalresource management, and how these two themes are integrated through responsible tourism practice. The study seeks to understand the nature and extent of the influence of tourism on both the well-being of social and natural systems in a rural, developing society. It further aims to inform entrepreneurs who are keen to improve their tour operations so as to practice responsible tourism. Primary data for this research was collected from a sample of fifty interviewees involving those who were directly involved in a tour operation at Malealea; those indirectly involved; and from those living in the surrounding area who were not involved in the operation in any way. Structured interviews were utilised for data collection. The results show that those directly involved with Malealea Lodge were able to enhance their skills through various education programs offered by the Lodge and were able toearn money to complement other sources of income. Alcohol abuse, child labour and uncontrollable children are reported as the most common negative impacts of the lodge on the host community. Most importantly, evidence of the integration of livelihoods and natural resource management in Malealea is limited. This conclusion is reached despite the fact that the management of the Lodge have established a few projects in an effort to address natural resources use and management concerns.
222

Can we go circular? : On the multifaceted challenges of facilitating shredder fines valorisation in the Swedish context

Gunaratne, Tharaka January 2020 (has links)
In concomitance with the growing developments around the circular economy concept in the region, the resource recovery and recycling of industrial production residues is increasingly being envisaged in the European Union and its member states. The role of the recycling industry has become ever important in this context. The shredding industry is based on shredding discarded products such as end-of-life vehicles, and municipal white goods, and subsequent retrieval of (primarily) metals. Shredder fines (or fines) is a heterogeneous fine-granular production residue of this industry, which is currently disposed of. Shredder fines presents, and will continue to do so in the foreseeable future, several challenges that need to be addressed. It creates a disposal problem given the shrinking landfill availability and incurs handling costs to the shredding industry. Furthermore, it reduces our resources efficiency in general. This thesis aims to contribute knowledge on the challenges of facilitating the valorisation of shredder fines in the context of Sweden. In doing so, the current situation concerning fines and its management was investigated by addressing the research questions; 1) What is the resource potential of fines generated at the studied shredding plant, and 2) Why is the current disposal-oriented management of shredder fines sustained in Sweden. There, a systems perspective was employed, where the research questions were addressed on the material, actor, and institution levels, based on three scientific articles, which are appended. The studied material carries a certain amount of potentially recoverable resources, nevertheless shows a significant need for upgrading pertaining to the user requirements and regulatory standards of different recovery applications. The full recovery of fines requires integrated processes that could simultaneously harness these resource opportunities and resolve the material constraints. When it comes to the current practice of managing fines in Sweden, the utilisation in landfill covering offers the shredding companies a secure outlet for the material, given it is a well-established practice that has evolved over decades of operations and there is still a significant demand for landfill cover materials. Additionally, it provides shredding companies with a legislatively-compliant low-cost disposal option for managing fines. On the other hand, the complex materiality, lack of marketability of secondary raw materials (SRMs), and unfavourable governmental regulation of waste recovery create strategic disincentives for shredding companies in opting for fines valorisation. Fines valorisation calls for change in the well-established current practice of utilising the material in landfill covering. Thus, drastic policy measures such as phasing out landfilling and mandating resource recovery and recycling of fines are required to remove the incentives for fines disposal and compel the shredding industry to seek valorisation alternatives for its management. In order to ensure long-term sustenance, applications based on fines valorisation need favourable and more predictable circumstances and settings on different societal levels. There, secure outlets for potential fines-derived SRMs is one of the essential elements. Governmental interventions to create demand and alleviate valorisation investments via market and financial instruments play a significant role in that regard. The other primary requirement to facilitate fines valorisation in the long term is to set clear market and regulatory playing rules. Established supply and demand structures would enable clear pricing mechanisms for fines-derived SRMs and accurate economic assessments of fines valorisation, thus reducing the investment risk for shredding companies. On the other hand, clear regulatory standards and favourable regulatory practices would reduce the uncertainty of the realisation of valorisation applications and gain trust among actors.
223

Vegetation and land-use data collection methods for environmental management purposes, with particular reference to the rivers entering False Bay, Cape, South Africa

O'Callaghan, M January 1985 (has links)
The increasing population and urbanization occurring in South Africa is threatening the survival of many environments, particularly those in close proximity to urban areas. Present legislation does not adequately protect the environment, and methods are needed to collect data to guide the development of conservation-orientated management and developmental policies. These data should provide a general description of the environment, Indicating sensitive areas, while taking physical, socio-economic and natural features into account. To be most meaningful, these data should be stored in a survey information system which is accessible to any person or institution involved in management or developmental policy formulation. Chapter 2 describes some of the components of such a system. Chapter 3 discusses the data collection component of the survey Information system. The use of vegetation features to describe the natural environment, and the use of land-use features for the socio-economic environment, are emphasized. Numerous methods are available to collect vegetation and land-use data, but for management purposes the methods should be elementary enough to be used by non-specialists while still supplying meaningful data. Aerial photography can be applied to vegetation and land-use studies. However, numerous inaccuracies can occur when using aerial photography as a source of data and Chapter 3 also discusses some of these limitations. The study area used to test proposed methods of collecting vegetation and land-use data for a management information system are described in Chapter 4. The study area consists of eleven study sites, each at a river mouth on the False Bay coast.
224

Återvinning av litiumjonbatterier : En jämförelse av metallutvinningsmetoder / Recycling of lithium-ion batteries : A comparison of metal extraction methods

Myhr Radell, Ingrid, Carlsson, Fanny January 2019 (has links)
Rapporten identifierar befintliga återvinningsmetoder för litiumbatterier och analyserar två avmetoderna på djupare nivå, en hydrometallurgisk metod och en pyrometallurgisk metod.Analysen är avgränsad till att utvärdera metoderna med Sverige som systemgräns och utifrånett ekologisk hållbarhets- och ekonomiskt lönsamhetsperspektiv. Verktyg som använts är enSWOT-analys som baseras på en litteraturstudie och intervju där kriterier identifierats. Dekriterier som valts för att utvärdera ekologisk hållbarhet är elkonsumtion, behov avkemikalier samt farligt avfall. De ekonomiska lönsamhets aspekterna har utvärderats medavseende på återvinningsmetodernas kapacitet, återvinnings- och reningsgrad,investeringskostnader samt metodkomplexitet. Analysen resulterar i att denpyrometallurgiska metoden är mest lämpad för Sverige i dagsläget eftersom den har högkapacitet och överensstämmer med befintlig infrastruktur. Andra slutsatser som dragits är attval av återvinningsmetod är kontextbaserat med stor vikt vid geografiskt område och tillgångtill batterimaterial. / The report identifies existing recycling methods for lithium batteries and analyzes two of themethods, a hydrometallurgical method and a pyrometallurgical method, on a deeper level.The analysis is limited to evaluating the methods with Sweden as a system boundary basedon environmental sustainability and economic profitability. Tools used are a SWOT analysisbased on a literature study and interview where criteria were identified. The criteria chosenfor evaluating environmental sustainability are energy consumption, the need for chemicalsand hazardous waste. The economic profitability aspects have been evaluated with respect tothe capacity of the recycling methods, recovery and purification, investment costs andmethod complexity. The analysis concludes that the pyrometallurgical method is mostsuitable for Sweden today as it has high capacity and conforms with existing infrastructure.Other conclusions drawn are that the choice of recycling method is context-based with greatemphasis on geographical location and access to battery material.
225

Flytande våtmark för dagvattenhantering i Rönningesjön, Täby kommun : Reningseffekt och framtidsutsikter

Dunér, Veronica, Myhrberg, Therese January 2014 (has links)
Täby kommun har sommaren 2013 infört en för Sverige ny dagvattenreningsteknik i form av en flytande våtmark, som har anlagts i Rönningesjön. Tekniken kan förklaras som en hybrid, där de biologiska reningsprocesserna liknar en naturlig våtmark, medan anläggningen hydrologiskt fungerar mer som en sedimentationsdamm. Att våtmarken är den första i Sverige gör det extra intressant att utvärdera. I och med denna rapport har dels en specifik undersökning av anläggningen gjorts, med särskild vikt vid det begränsande näringsämnet fosfor. Vidare ges en bredare överblick av tekniken som sådan och dess framtidsutsikter i Sverige. För att bedöma anläggningens reningseffekt har flödesmätningar och provtagningar vid in- och utlopp gjorts under en period mellan vecka 15-24 2014. Analysen har sedan gjorts med avseende på fosfor, pH, konduktivitet och turbiditet. Utifrån undersökningen har beräknats att det vid utloppet till anläggningen skett en minskning av medelkoncentrationen totalfosfor med 9,4 %. Denna relativt låga reningseffekt förklaras utifrån en förhållandevis låg fosforhalt överlag vilket skulle kunna göra att våtmarken inte når sin maximala effektivitet, samt att anläggningens unga ålder gör att den ännu inte är fullt utvecklad. En ytterligare förklaring kan vara att det i denna begränsade studie har behövt göras ett antal förenklingar och antaganden, vilket innebär osäkerheter i resultatet. Reningseffekten bör därmed snarare ses som en riktlinje än ett absolut värde. För en mer komplett bild av våtmarkens reningskapacitet bör ytterligare analyser göras, och även på parametrar som denna undersökning ej tar hänsyn till, som exempelvis rening av kväve och tungmetaller. Vad gäller teknikens framtidsutsikter i Sverige finns det flera fördelar som talar för en fortsatt etablering. Tekniken är billig och i princip underhållsfri. Dessutom lämpar den sig väl att använda som komplement till redan befintliga anläggningar. Å andra sidan är det Svenska klimatet inte optimalt i och med långa vintrar med låg biologisk aktivitet vilket skulle kunna göra att effektiviteten i Sverige blir lägre än i varmare länder där tekniken använts tidigare. / The municipality of Täby has in the summer of 2013 introduced a storm water treatment technology, new to Sweden, in the lake Rönningesjön. The technology, which is called floating treatment wetlands (FTWs), can be explained as a hybrid system, where the biological treatment mechanisms are similar to the ones of a natural wetland, while the facility hydrologically behaves like a retention pond. This report is the result of a first examination of the water purification capacity, where the removal capacity of phosphorus has been of particular importance. Furthermore, the techology and its future prospects is being discussed in a wider perspective. To evaluate the removal capacity, a series of flow measurements and collection of water samples has been executed in a period between week 15-24 in the year of 2014. The analysis has subsequently been done in regard to the parameters total phosphorus, pH, conductivity and turbidity. The results show a reduction of mean total phosphorus betwen inflow and outflow by 9,4 %. This relatively low efficency may depend on the overall low concentrations of phosphorus, while the wetland reaches its maximum capacity at higher concentrations. Furthermore, the wetland may not be fully developed due to the youth of the facility why an improvement of efficiency could be expected over time. A further explanation could be that in this limited study, some simplifications and assumptions has been neccesary to do, and these provides some incertainty in the results. The removal efficiency should thereby rather be seen as a guideline. To provide a complementary view of the FTW removal capacity, further analysis should be executed, and also in parameters such as nitrogen and metal removal, which this study has not taken into account. Regarding the future prospects of the technology in Sweden there a several advantages proposing a continued establishment. The technology is inexpensive and requires a low maintenance. It is also suitable to use as a complement to existing facilities. On the other hand long winters in Sweden with low bioactivity may reduce the efficency compared to other countries where the technology previously has been used.
226

Effects of Varying Sludge Quality on the Permeability of a Membrane Bioreactor

Apostolopoulou - Kalkavoura, Varvara January 2014 (has links)
This master thesis firstly includes a theory part describing, the conventional municipal wastewater treatment plant (WWTP) and especially the conventional activated sludge (CAS) process. As Stockholm municipality want to retrofit the current activated sludge system at Henriksdal into a membrane bioreactor (MBR), an extensive description of the MBR and its advantages and disadvantages are included. Fouling is considered a really important issue for the operation of an MBR since it reduces an MBR’s productivity over time. Therefore, description of the fouling mechanisms and the potential foulants is included as well as a description of the membrane cleaning procedures. Sludge composition is considered a very important parameter which contributes to membrane fouling and thus this master thesis aims to identify the effects of varying sludge quality on the membranes operation. Precipitation chemicals used for phosphorus chemical precipitation and especially ferrous sulphate which is examined in this master thesis are also affecting the sludge quality and the membranes operation. The report includes description of Henriksdal reningsverk and line 1 of the pilot MBR at Hammarby Sjöstadsverk where the experimental work was performed. The following chapter describes the experimental work performed in the laboratory including the determination of total suspended solids (TSS), volatile suspended solids (VSS), sludge volume index (SVI) and sludge’s filterability. The filterability was determined by performing the time to filter (TTF) method and the sludge filtration index (SFI) method. Furthermore, the samples were also examined in the optical microscope to determine their bulkiness and their filaments content. The iron content in the sludge was also measured from Eurofins Environment Testing Sweden AB. In the results section, the different parameters measured are illustrated in charts and they are compared to each other in order to define which factors contribute positively or negatively to the sludge’s filterability and thus affect the sludge quality and the membranes operation. The results indicate that SFI is a more reliable method for measuring filterability compared to TTF. Furthermore, the iron content in the sludge is proportional to the permeability as well as the filaments content observed during microscopy is proportional to the SFI or TTF. Finally, this master thesis includes recommendations for future research which basically include more analyses to identify the sludge biology and more samples taken for longer time periods.
227

Holistic Energy Analysis of Municipal Wastewater Treatment & Sludge Handling

Taylor, Shannon January 2014 (has links)
Municipal wastewater treatment and associated sludge handling is an essential process for modern society and contributes to both human and environmental health. However, it is energy intensive. There has been a focus on cleaning efficiency in the subprocesses, e.g. activated sludge treatment; however, a holistic approach that reviews different system setups in detail is lacking. The aim of this project is to analyze the mass and energy flows through core municipal wastewater treatment plant (WWTP) subprocesses and propose holistic measures to improve the total efficiency. Two configurations for sludge-handling are proposed: incineration and gasification; additionally, detailed models of the mass and energy flows in/out of each subprocess are created. Unit processes such as a heat pump, heat exchangers, and combined heat and power plants are incorporated into each model configuration to maximize the energy efficiency. The result is that the gasification option is self-sufficient in heat and saves over half of the electricity needs. The incineration option is also self-sufficient in heat but still requires significant electricity. Both options contain inspiring characteristics for the future generation of WWTPs.
228

How might the collaborative economy influence sustainability of tourism in Barcelona?

García Betorz, Sara January 2014 (has links)
The aim of this project is to analyze how the Collaborative Economy (CE) might influence sustainability of tourism in Barcelona.<img src="file:///page4image78608" /> Since The Olympic Games in 1992, Barcelona has become a leader in many aspects, but especially in the tourism sector. Nowadays the city is a highly popular tourist destination and the tourism industry has made a significant contribution to the economics of Barcelona with the creation of income, taxes, hard currency and jobs (Sirakaya, Jamal, &amp; Choi, 2001). Despite the high success achieved by “model Barcelona” it is important to take into account some challenges faced by the city in terms of tourism, creating a need for alternative and more environmentally and host-friendly practices in development, planning, and policies (Saarinen, J. 2006). One example of this is CE, which, since 2011, has started to have an impact on the Catalan capital, and all indicators show that the peer to peer (P2P) sites are one of the technology trends that are already radically transforming tourism (Sunyer, 2014). Collaborative consumption was named one of TIME Magazine's 10 ideas that will change the world. All we do, create and produce has an impact on the environment (tourism generates an impact as well as the CE) and measuring the impact of our actions helps us to know where to improve and develop better strategies. The questions now are: what is the real impact that these new systems have on the city? Do they contribute to the path of sustainable tourism? To answer these questions and form a point of departure for this study, I interviewed different stakeholders: twelve experts from CE and tourism in Barcelona and 49 students from UAB University under the Tourism Grade. Interviews made to experts were based on face to face meetings carried out in two parts; firstly semi-structured questions and secondly a survey based on an evaluation of a previously selected tourism system indicator. The survey consisted of the evaluation of the European Tourism Indicators System – ETIS for Sustainable Destinations, where the interviewees had to evaluate the influence of CE through the validation of the 27 core indicators (deciding whether the indicator would increase, decrease or remain equal with the influence of the CE). The interviews conducted with the forty-nine students were made online and based on the survey evaluation of ETIS (like with the experts). The results show that CE could generate a better distribution of income around the city and could support the process of descentralization of tourism activity in the city center. Furthermore, it could strengthen social relations between locals and visitors, and thereby improve the negative perception that mass tourism generates in some specific points like Ciutat Vella. According to the stakeholders interviewed, the influence of CE in Barcelona could ensure a higher rate of satisfaction among tourists and increase the number of strategic plans of the city in terms of sustainability. On the other hand, it is noteworthy to consider the negative effects that CE could generate; the more distribution the city has, the more social friction is generated and so more specific managing plans are needed. Furthermore, interviewees considered that the occupancy rate in commercial accommodation and direct tourism employment would decrease, which means less income from the “traditional” tourist enterprises. The results also illustrate a lack of understanding of the CE and sustainable tourism concepts. Although experts were familiar to both concepts, researchers and tourism managers had a better understanding of sustainability in tourism while promoters of the CE were the stakeholders with more knowledge about the Collaborative movement. There is still a need of more comprehension of both terms. There are three elements to consider for discussions which concern respondents with such a variety of opinions depending on their background; 1) the understanding of the two concepts (CE and sustainable tourism) of the case from the all stakeholders involved. If there is a lack of comprehension of both it is just impossible to apply them; 2) the regulation process of the CE which nowadays has split the opinion of the population and 3) the carrying capacity that the city can support. They are the key elements to discuss in the collaborative economy wave. Nonetheless, one must consider what CE means, what its main principles are and why it exists and connect all these with the necessities related with tourism, which presents a considerable challenge in certain parts of the world. Only when an appropriate comprehension of the “core” and “essence” of both concepts is achieved will we be able to connect them, understand their strengths and weaknesses and aim for genuine sustainable development.
229

Pyrolysis of Waste Electrical and Electric Equipment (WEEE) for Energy Production and Material Recovery

EVANGELOPOULOS, PANAGIOTIS January 2014 (has links)
This master thesis focuses on pyrolysis of electronic waste (e-waste) for energy production and material recovery. Firstly, in the theoretical section a description of electronic waste their composition and the current waste management techniques is presented in order to get insights about their properties. As more and more sustainable solutions are required for waste handling, the advantages and disadvantages of the current treatment methods are analyzed in order to compare them with the innovative technique of waste pyrolysis. The substrate used for pyrolysis in terms of this master thesis was the printed circuit boards’ fraction (PCBs) and thus a particular description of this fraction is included. Furthermore, the pyrolysis as a thermal treatment method is fully described for getting an overview of the entire process. The next section of the current master thesis includes a description of the instrumentation used for conducting the experimental part, the thermogravimetric analysis (TGA) and the Analytical Pyrolysis (PY-GC-MS). The experimental part included as well the samples preparation in order to obtain a homogeneous mixture since various substances are used for PCBs manufacturing. Furthermore, samples were sent to an external company for elemental, proximate and ultimate analysis. After the samples preparation, the TGA and GC-MS were both used as analytical tools in order to identify the main substances produced, the reactions kinetics taking place, and various others important parameters. Furthermore, the results derived from the experimental were further analyzed using various calculations tools such as Microsoft Office Excel and Matlab as well as the software of GC-MS. The results section also includes a deep discussion of the results since the pyrolysis of electronic waste is still under research an extensive analysis is necessary. Summarizing, the results illustrates all the data gathered from the composition analysis, the TGA curves and a qualitative and quantitative analysis. The main product of pyrolysis of printed circuit boards is phenol and hydrocarbons with high heating value, while the increased ash content is promising for the recovery of metals. Finally, the report includes several recommendations for the future work to be done and the basic directions for the research of pyrolysis process for materials and energy recovery should get.
230

A literature study on the cleaning of streets in Stockholm city : The flow of snow and dust

Palén, Jennifer January 2014 (has links)
Stockholm, the capital of Sweden, is a big city with almost one million citizens. The city have got almost 4000 streets of different kinds and it is therefore important to see how the city's cleaning of streets is being managed. The surrounding environment is widely affected by it and a lot of money is being invested in the area since the city is interested in minimize its environmental impact. This study is a literature study which addresses the two largest parts in cleaning of streets, handling of street snow and street dust. It will elucidate how these two flows appears, interact and effect each other as well as how they circulate and recirculate in the city. The report will highlight that the city of Stockholm is doing a lot to minimize the environmental impacts of these flows but also discuss what the city can do to become even better within cleaning of streets from an environmental point of view. / Stockholm, Sveriges huvudstad, är en stor stad med nästan en miljon invånare. Staden har ungefär 4000 gator av olika slag och det är därför viktigt att se hur stadens renhållning av gator hanteras. Den omgivande miljön påverkas stort av detta och en massa pengar investeras inom området eftersom staden är angelägen om att minimera sin miljöpåverkan. Denna studie är en litteraturstudie som behandlar två största delarna inom renhållning av gator, nämligen hantering av gatusnö och gatudamm. Den kommer att belysa hur dessa två flöden ser ut, samverkar och påverkar varandra samt hur de cirkulerar och återcirkulera i staden. Rapporten kommer att belysa att Stockholms stad gör en hel del för att minimera miljöpåverkan av dessa flöden men kommer också det att diskutera vad staden kan göra för att bli ännu bättre inom renhållning, utifrån ett miljöperspektiv.

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