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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.
251

An investigation into effectiveness of household solid waste management strategies in Harare, Zimbabwe

Mandevere, Benjamin 20 April 2016 (has links)
The main objective of the study was to investigate the effectiveness of the strategies employed by the City of Harare in household solid waste management. To achieve these, structured questionnaires, interviews, observations and focus group discussions were employed in data gathering together with secondary data. The study was conducted in Harare’s low, medium and high density income suburbs. Findings revealed that organic solid waste constituted the largest proportion of waste generated in Harare and other forms are also generated yet their collection is very minimal. Residents resort to illegal night dumping, resulting in the proliferation of associated diseases. In light of these findings, it was recommended that waste collection entities be capacitated, people be educated on waste recycling, reduction and reusing. A commission was to be put in place to ensure proper enforcement of waste legislation, effective and sustainable day in running of household solid waste management in the city / Environmental Sciences / M.Sc. (Environmental Management)
252

Environmental Systems Analysis Tools as Decision-Support in Municipal Solid Waste Management : LCA in Sweden, Estonia and Lithuania

Johnson, Amanda January 2013 (has links)
In order to deal with the mounting issue of Municipal Solid Waste (MSW) in a way that is in line with sustainable development and Integrated Solid Waste Management (ISWM) a systems approach is necessary.This approach can practically be integrated into the MSW decision-making process through Life Cycle Thinking(LCT) and environmental systems analysis tools such as Life Cycle Assessment (LCA). This paper is written within the context of the RECO Baltic 21 Tech (RB21T) project which aims to improve waste management practices in 12 countries in the Baltic Sea Region. The main aim of this paper is to investigate the extent to which LCA is used as decision-support in MSW management in Sweden, Estonia and Lithuania. The use of LCA is examined on a national level as well as on a local or regional level based on relevant literature and a set of interviews conducted in each country. According to the results the use of LCA as decision-support in MSW management is very limited in Estonia and Lithuania whilst it is already a well-established tool in Sweden. Most of the LCA efforts in the Baltic States have been conducted in connection with foreign projects and investments,such as RB21T. Although an actual LCA might not always be applied in Sweden, LCT is prevalent in MSW management both on a national and local level. In order for LCA to be better integrated into MSW management this paper argues that there is a need for increased knowledge, data, more user-friendly LCA-tools andstrengthening regional partnerships for further transfer of knowledge between countries.
253

Skarreling for Scrap: a case study of informal waste recycling at the Coastal Park landfill in Cape Town

Huegel, Christoph Peter January 2011 (has links)
A widespread phenomenon on dumpsites in the developing world, subsistence waste picking is also a common practice at the city-owned Coastal Park Landfill (CPL) in Muizenberg. Poor unemployed people from the townships of Capricorn, Vrygrond and Hillview, situated at the foot of the tip “skarrel for scrap” every day. The word skarreling is an Afrikaans term meaning to rummage or scrabble, scuttle or scurry. Thus, if one talks of “skarreling for scrap”, it generally refers to poor peo-ple trying to eke out a living by looking for recyclables in the waste that can be put to personal use or turned into money.In the two decades since the transition to democracy, South Africa and the City of Cape Town (CCT) have formulated a number of framework and subordinate policies which express their commitment to sustainable development (SD). SD aims to achieve a balance between its three components, econom-ic, environmental and social sustainability. Thus, SD is not only about increased economic efficiency and stability, while at the same time reducing pollution and handling natural resources more thought-fully; it is also about promoting social equity by reducing poverty and empowering the poor. This study is guided by the assumption that waste pickers in developing countries play an important part in recycling efforts, and that recycling in turn is an integral component of SD, which is the guid-ing principle of South African policy-making. In an ideal scenario – as implicitly promised by the policies on SD – the management of solid waste should pursue the economic and environmental goals of SD by promoting recycling and should be aligned with the goal of creating sustainable livelihoods.However, the reality in the CCT is a different one. Landfill skarreling in the CCT, and particularly at CPL, is accompanied by conflict and a criminalisation of the skarrelaars. The CCT decided to phase out landfill salvaging in 2008, and subsequently has put a lot of effort into keeping skarrelaars away from its landfills. The implications of this decision – job losses for poor people and a potential in-crease in crime – have not been thought through. There is thus a dysfunctional triangular relationship around waste recycling in the CCT, leading to tensions between (1) the City’s commitment to SD; (2) its approach towards recycling (as part of solid waste management) in policy and practice; and (3) the livelihoods of the poor in adjacent townships. In the CCT the goals of SD are undermined by the City’s recycling strategies, with adverse effects for the livelihoods of the people who live off skarrel-ing.There are several causes for this disjuncture between policy and reality. The first has to do with igno-rance on the side of the policymakers. They seem to be badly informed about the extent and nature of skarreling, perhaps assuming that this activity is performed only by a few people who need quick cash for drugs. The second cause can be attributed to the neoliberal macro-policies pursued in South Africa, as well as to the global competition between cities for investment. This neoliberal urbanism leads cities like Cape Town to re-imagine themselves as “world (-class) cities”, in which poor waste pickers are perceived as a disturbing factor. In the CCT, this goes hand in hand with an approach reminiscent of the apartheid mindset, which saw the need to control poor, black (and potentially unru-ly) people.The dissertation therefore focuses on the core themes of sustainable development, (urban) neoliberal-ism, and informality in combination with a case study of the informal waste pickers at the chosen landfill site. Writing from a political studies angle, this study is framed as a policy critique: it argues that the policies around SWM ignore South African realities, and that the SD policies and their im-plementation lack coherence. Moreover, the conflict between the skarrelaars and the CCT at the CPL is rooted in inadequate national and local legislation which does not acknowledge the role of informal waste pickers in SWM and aims at excluding rather than including them. If waste pickers were sup-ported in their recycling efforts in both policy and practice, this would be a win-win situation for the state/city (economic benefits and less crime), the skarrelaars (regular employment and incomes) and the environment (less waste buried on landfills).The case study is primarily designed as a qualitative study, but also includes quantitative elements as it attempts a first quantification of the extent and nature of skarreling at the CPL site, one of only three operating dumpsites in Cape Town. The aim on the one hand is to estimate the contribution of the skarrelaars to waste reduction (and therefore to sustainability) in the City, especially since the waste they collect is not buried on the landfill, thereby prolonging the operational life span of the landfill. The other aim is to assess the role of the skarrelaars as an economic factor in the township, in particular the question of how important the incomes generated from skarreling are for their individu-al livelihoods and for the community as a whole. / Magister Artium - MA
254

Mixed fuels composed of household waste and waste wood : Characterization, combustion behaviour and potential emissions

Edo Giménez, Mar January 2016 (has links)
Incineration with energy recovery is the main disposal strategy for waste that cannot be reused or recycled, and a well-established source of energy in Europe, especially in Sweden where 2.2 Mtonnes of waste including domestic and imported municipal solid waste (MSW) and waste wood (WW) were combusted during 2015. However, owing to its inherent heterogeneous composition, inclusion of such waste in Waste-to-energy (WtE) technologies is challenging. These heterogeneities may lead to operationally-related issues in the WtE facilities and contribute to toxic emissions, which can be reduced by waste pre-treatment technologies.    This thesis examines the variations in the composition of MSW and WW streams used as a fuel supply in WtE facilities after undergoing waste pre-treatment technologies, and the effect of fuel composition on its combustion behaviour and formation of persistent organic pollutants (POPs) such as polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The overall objective is to contribute to a more thorough understanding of the selection of waste pre-treatment technologies to mitigate harmful emissions into the atmosphere when waste fuels are combusted in WtE facilities.    This thesis describes the high variability of contaminants in domestic and imported WW and suggests adaptation of WW pre-treatment techniques to produce fuels with a low potential for generating pollutants. A comparison of mechanical solid waste pre-treatments revealed that screening and shredding is more efficient than extrusion for reducing emissions of pollutants such as PCDDs and PCDFs in combustion. The evaluation of the combustion behaviour of MSW-based fuels showed a three-stage oxidative decomposition, and an acceleration of the decomposition of the MSW compared to the lignocellulosic materials, which may be attributed to the presence of food waste and plastics in the MSW. Combustion tests of fuel blends containing WW and MSW-based fuels with different food waste content suggested that WW, not food waste content, is the key factor for the formation of PCDDs, PCDFs, and polychlorinated biphenyls (PCB), benzenes (PCBzs) and phenols (PCPhs). Torrefaction may be a suitable technology for improving the properties of waste as a fuel e.g. due to its low PCDD and PCDF emissions. / Förbränning med energiåtervinning är det huvudsakliga sättet att ta hand om avfall som inte kan återanvändas eller återvinnas. Det är en väletablerad energikälla i Europa och särskilt i Sverige där 2,2 miljoner ton avfall, däribland inhemskt och importerat hushållsavfall och returträ, förbrändes under 2015. På grund av den heterogena sammansättningen hos hushållsavfall och returträ är förbränning av dessa material i anläggningar med energiåtervinning (så kallade WtE-anläggningar) förknippade med en del driftsrelaterade utmaningar. Det kan även ge upphov till miljöfarliga utsläpp, som dock kan reduceras genom förbehandling av avfallet. I denna avhandling har variationer i sammansättningen hos hushållsavfall och returträ som förbränns i WtE-anläggningar undersökts. Effekten av bränslemixens sammansättning och ev förbehandling på bränslets förbränningsegenskaper samt bildning av långlivade organiska föroreningar (så kallade POPar) såsom polyklorerade dibenso-p-dioxiner och polyklorerade dibensofuraner vid förbränning har utvärderats. Det övergripande målet är att bidra till en djupare förståelse av hur valet av förbehandlingsteknik för avfall kan bidra till att minska skadliga utsläpp till luft när avfallsbränslen förbränns i WtE-anläggningar. Denna avhandling beskriver den stora variabiliteten av metall- och materialföroreningar i inhemskt och importerat returträ och föreslår förbehandlingstekniker för att producera bränslen med låg potential att generera föroreningar. En jämförelse av mekaniska förbehandlingstekniker visade att mekanisk sönderdelning och separering (krossning och siktning) är mer effektivt än s.k. högtrycks-pressning för att minska utsläppen av föroreningar som dioxiner och furaner vid förbränning. Utvärderingen av bränslemixar innehållande hushållsavfall uppvisade en oxidativ nedbrytning i tre steg vid förbränning, och en accelererad nedbrytning av avfallsmaterialet jämfört med vedmaterialet i bränslet, troligen som effekt av innehållet av matavfall och plast i hushållsavfallet. Förbränningsförsök med bränsleblandningar av returträ och hushållsavfall med olika innehåll av matavfall visade att mängden returträ, och inte mängden matavfall, är den viktigaste faktorn för bildning av dioxiner, furaner, klorbifenyler, klorbensener, och klorfenoler. Torrefiering kan vara en lämplig teknik för att förbättra avfallets bränsleegenskaper, t.ex. på grund av dess låga emissioner.
255

The Analysis of PCDD and PCDF Emissions from the Cofiring of Densified Refuse Derived Fuel and Coal

Moore, Paul, 1962- 08 1900 (has links)
The United States leads the world in per capita production of Municipal Solid Waste (MSW), generating approximately 200 million tons per year. By 2000 A.D. the US EPA predicts a 20% rise in these numbers. Currently the major strategies of MSW disposal are (i) landfill and (ii) incineration. The amount of landfill space in the US is on a rapid decline. There are -10,000 landfill sites in the country, of which only 65-70% are still in use. The Office of Technology Assessment (OTA) predicts an 80% landfill closure rate in the next 20 years. The development of a viable energy resource from MSW, in the form of densified Refuse Derived Fuel (dRDF), provides solutions to the problems of MSW generation and fossil fuel depletions. Every 2 tons of MSW yields approximately 1 ton of dRDF. Each ton of dRDF has an energy equivalent of more than two barrels of oil. At current production rates the US is "throwing away" over 200,000,000 barrels of oil a year. In order to be considered a truly viable product dRDF must be extensively studied; in terms of it's cost of production, it's combustion properties, and it's potential for environmental pollution. In 1987 a research team from the University of North Texas, in conjunction with the US DOE and Argonne National Laboratory (ANL), cofired over 550 tons of dRDF and bdRDF with a high sulfur Kentucky coal in a boiler at ANL. This work examines the emission rates of polychlorinated dioxins (PCDDs) and furans (PCDFs) during the combustion of the dRDF, bdRDF, and coal. Even at levels of 50% by Btu content of dRDF in the fuel feedstock, emission rates of PCDDs and PCDFs were below detection limits. The dRDF is shown to be an environmentally acceptable product, which could help resolve one of the major social and environmental problems facing this country today.
256

Manufacturer [Sic] of Densified-Refuse Derived Fuel (d-RDF) Pellets and Methods for the Determination of d-RDF Pellet Densities

Attili, Bassam Saleem 12 1900 (has links)
There are 150 million tons of Municipal Solid Waste (MSW) annually produced in the United States, which is approximately equivalent to 150 million barrels of oil. MSW production is inexhaustible, and is increasing on an annual per capita basis of approximately three per cent. After controlling the moisture and adding a binder, the combustible portion of MSW was converted to pellets. The objects of this project were to 1) evaluate the binder, 2) prepare the pellets, and 3) evaluate the pellets with regard to density. The manufacture of pellets was conducted at the Naval Air Station, Jacksonville, Florida. The evaluation of the binders and the pellets was done at North Texas State University (NTSU). There were three procedures for measuring the density. The first, using water displacement, was from the American Society for Testing and Material (ASTM). The second, using wax coating, was also from ASTM. The third, using sharply-cut cylindrical pellets, was developed at NTSU.
257

Characterizing the Municipal Solid Waste Stream in Denton, Texas

Brady, Patricia D. 08 1900 (has links)
Forty-two commercially collected dumpsters from Denton’s Municipal Solid Waste Stream were emptied, sorted and weighed to characterize the material types and make preliminary recycling policy recommendations. The general composition of Denton’s solid waste stream was not significantly different from the composition of the nation’s solid waste stream. Fifty-eight percent of the observed waste stream was recyclable. Paper made up the largest portion of recyclable materials and the "grocery" source category had more paper than any of the other five categories. Based on these findings, an incrementally aggressive approach is recommended to reduce certain types of wastes observed in the waste stream. This would include a Pay-As-You-Throw Program followed by an Intermediate Processing Center that can be converted to a Materials Recovery Facility.
258

Differences between urban and landfill citizens in the An Giang province of Vietnam : - a field study about landfilling & solid waste management

Jonsson, Nina January 2019 (has links)
Landfilling is the most common treatment of Municipal Solid Waste (MSW) in the An Giang province in south Vietnam. Many of the landfills are not sanitary and can be harmful to the environment and the residents, especially those who live within the settled distance limit of 1000 meters. There is a lack of knowledge about the people living close to landfills in the An Giang province. Therefore, the aim of the study was to investigate any issues about living close to landfills, by comparing health, knowledge and social issues, between people living near landfills and people in urban areas in the An Giang province. A total of 80 people was chosen in Long Xuyen and An Phu, for a questionnaire. The data was compiled and coded in Excel for further analyzation in SPSS. The results show differences in social issues, health and knowledge related to landfilling and solid waste. The experiences in the landfill areas could be taken in advantage. The study suggests using students in communication programs and workshops to increase knowledge and practice about solid waste among the citizens. To monitor landfills and the air in due to open burning of solid waste, is recommended. / Deponering är den vanligaste behandlingen av hushållsavfall i An Giang-provinsen i södra Vietnam. Många av dessa soptippar (deponier) är inte sanitära och kan vara skadliga för både miljön och invånarna som bor inom den bestämda avståndsgränsen på 1000 meter. Det finns brist på kunskap om de människor som bor nära deponier i An Giang-provinsen. Därför var syftet med studien att undersöka förekomsten av problem av att bo nära deponier i provinsen. Detta gjordes genom att jämföra hälsa, kunskap och sociala frågor mellan människor som bor intill deponier och människor i urbana områden. Totalt valdes 80 personer i Long Xuyen och An Phu till en enkätstudie. Uppgifterna sammanställdes och kodades i Excel för vidare analys i SPSS. Resultaten visade skillnader i sociala frågor, hälsa och kunskap relaterade till deponering och fast avfall. I deponiområdena fanns det mycket erfarenhet som skulle kunna utnyttjas. Studien föreslår bl.a. att använda skolungdomar i kommunikationskampanjer och workshops för att öka kunskap och praxis hos invånarna. Att övervakning och mäta deponier och luften p.g.a. öppen eldning av avfall, rekommenderas.
259

Impacto ambiental gerado pela disposição de areias de fundição: estudo de caso / Environmental impact generated by foundry sand disposal: case study

Penkaitis, Gabriela 26 March 2012 (has links)
A disposição de areia de fundição em áreas não licenciadas foi uma prática até pouco tempo empregada por muitas empresas do setor. Em função dessa prática estuda-se nessa dissertação um passivo ambiental produzido em uma área no estado de São Paulo, que recebeu resíduos de fundição e pouco se sabe sobre o impacto ao meio ambiente ocasionado pela disposição inadequada desse material. O presente trabalho propõe avaliar potenciais impactos no meio ambiente pela disposição deste resíduo em um aterro não controlado de uma indústria de fundição e promover análise crítica diante das atuais normas e ferramentas de análises de impactos ambientais e classificação de resíduos sólidos, verificando eventuais conflitos entre as atuais ferramentas aplicadas. Para essa avaliação, foram empregadas algumas ferramentas de investigação científica como Microscopia Eletrônica de Varredura compreendendo análise morfológica e química qualitativa do resíduo depositado, análise granulométrica e análise química das águas subterrâneas, a partir de amostragens realizadas em campo e dados fornecidos por empresa de recuperação ambiental que atua na área. Assim foram obtidos dados que permitiram caracterizar a área, monitorar a qualidade das águas subterrâneas dentro e no entorno do aterro e caracterizar o resíduo sólido em questão, onde se analisou as questões ambientais e legais com base nas atuais normas e ferramentas de gestão de áreas contaminadas e resíduos sólidos. Os dados obtidos a partir das análises das amostras de água e resíduo demonstram clara e forte concentração de metais nas águas (ferro, manganês, boro e selênio) e no resíduo (cromo, cobre, cobalto, níquel, zinco, alumínio, ferro, manganês), no caso desse último, dentro dos limites da atual normatização para classificação, identificando-o como resíduo não perigoso. Ainda que esse não seja considerado perigoso, a identificação de elementos nas águas em concentrações acima do permitido compromete a qualidade ambiental do local, colocando em risco a população do entorno, visto que em suas adjacências algumas propriedades realizam cultivo agrícola, além de extrair água do subsolo. Evidenciase, a partir desse cenário, a necessidade de estreitamento técnico entre as atuais normas e ferramentas de análises de impacto ambiental e classificação de resíduos sólidos, permitindo realizar avaliações de passivos gerados pela disposição inadequada de resíduos que levem em consideração suas possíveis interações com o ambiente ao longo de seu tempo de exposição. / The disposal of foundry sand illegal areas was a practice until recently employed by many companies. Because this practice is studied in this dissertation an environmental liability produced in a land in the state of São Paulo that received foundry waste and little is known about the environmental impact caused by inadequate disposal of this material. This issue proposes detected the real effect in the environment by the disposal of this waste in an uncontrolled landfill foundry industry and promote critical analysis before the current standards and tools of environmental impact analyses and classification of solid waste, checking possible conflicts between the current tools applied. For this evaluation, some scientific research tools were employed as Electronic Microscopy of Scan including morphological and chemical waste analyses, particle size analysis and chemical analysis of groundwater samples collected from the field and data provided by an environmental recovery company that operates in the area. Thus data were obtained which allowed to characterize the area, monitor the groundwater quality in and around the landfill and to characterize the solid waste in question, which examined the environmental and legal issues based on current standards and management tools of contaminated lands and solid waste. The data from the analyzes of samples of water and waste show a clear and strong concentration of metals in water (iron, manganese, boron and selenium) and in the waste (chromium, copper, cobalt, nickel, zinc, aluminum, iron, manganese), in the last one according to current regulation for classification, identifying it as not dangerous. Although the waste is not considered dangerous, the identification of elements in water at concentrations above permitted to compromise the quality of the local environment, endangering the surround population, since in its surrounding some properties carry out agricultural, in addition extracting groundwater. It is evident from this scenario, the need for technical narrowing between the current standards and environmental impact analyzes tools and classification of solid waste, permitting carry out evaluations of liabilities generated by inadequate disposal of waste that take into account their possible interactions with the environment over time of exposure.
260

Arqueologia do Lixo: um estudo de caso nos depósitos de resíduos sólidos da cidade de Mogi das Cruzes em São Paulo / Archaeology of Garbage: a study of case in the solid waste landfill of the city of Mogi das Cruzes in Sao Paulo

Andrade, André Wagner Oliani 04 July 2006 (has links)
A presença do lixo como parte integrante e inevitável na vida do homem, o qualifica como um importante agente de interação nos mais diversos setores de atividade. A partir de uma visão holística, os resíduos sólidos relacionam-se com questões como energia, educação, saúde e saneamento, recursos naturais, geração de renda e de empregos, turismo e recreação, direito e cidadania, meio ambiente etc. (Andrade, 2001), através de várias áreas de conhecimento como Antropologia, Engenharia, Física, Química, Biologia, Geofísica, Economia, Geografia, Sociologia, Direito, entre tantas outras, inclusive ARQUEOLOGIA, principal objeto de interface deste trabalho. Neste sentido, o principal objetivo deste trabalho é apresentar uma metodologia que, através das técnicas de escavação, interpretação e análises arqueológicas, favoreça uma compreensão maior sobre as questões históricas, sociais, culturais, econômicas e ambientais relacionadas aos resíduos sólidos (lixo), visando encontrar informações que norteiem a gestão dos mesmos através de procedimentos que atendam às particularidades de uma fonte geradora específica. O projeto foi fundamentado em um estudo de caso, através da investigação do depósito de resíduos sólidos de Volta Fria na cidade de Mogi das Cruzes, localizada na região metropolitana de São Paulo. / The presence of solid wastes as an integrant and inevitable part in the life of the human being, characterizes it as an important agent of interaction in the most diverse sectors of activity. From a holistic vision, we relate the wastes to issues such as education, citizenship, health, sanitation, energy and environment, through knowledge areas as anthropology, engineering, chemistry, biology, economy, sociology and also archaeology. The purpose of this work is to show how techniques of archaeological intervention and interpretation can assist in the understanding on historical, social, cultural, economic and environmental questions related to the municipal solid wastes, aiming at to find information that guide its management in a specific generating source. Supporting our analysis the methodology of archaeological inquiry applied for the study of case in the Volta Fria landfill of the city of Mogi das Cruzes in Sao Paulo state, will be presented.

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