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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.
101

Evaluation of landfill leachate treatment using aerobic granular sludge and activated sludge processes

Ren, Yanan 09 March 2017 (has links)
The treatment of synthetic landfill leachate and raw landfill leachate were investigated using two sets of 3 L aerobic sequencing batch reactors (SBR): activated sludge SBR (ASBR) and granular SBR (GSBR). In synthetic young landfill leachate treatment, GSBR was more efficient in nitrogen and carbon removal than ASBR. During the steady period of the experiment, 99% total ammonium nitrogen (TAN) was removed through nitritation and nitrification in GSBR with an average influent TAN concentration of 498 mg/L. On the contrary, complete nitrification was not achieved in ASBR with a nitrification efficiency of 77±10%. GSBR also presented higher efficiency in denitrification and COD removal compared to ASBR. Phosphorus removal efficiency was almost identical in both reactors. Synthetic old landfill leachate treatment using GSBR maintained the stable COD removal efficiency at 66%, when the ammonia nitrogen to the maximum of 465±46 mg/L. The ASBR required a start-up of at least 30 days and removed 59±9% of COD when an influent ammonia nitrogen concentration about 200 mg/L. The GSBR was also more efficient than the ASBR for nitrogen removal. The granular sludge reached a maximum ammonia removal of 95±7%, whereas 96±5% was achieved by ASBR. The phosphorus removal was likely affected by the free nitrous acid (FNA) and the low biodegradability of tannic acid. In raw landfill leachate treatment, the total ammonia nitrogen (TAN) removal efficiency was in GSBR approximately 99.7%. However, the ASBR treatment did not show a consistent performance in TAN removal. TAN removal efficiency decreased with increasing ammonia concentration in the influent. Nitrification in GSBR was partially inhibited at FA concentrations of 48 to 57 mg/L, which was two times more than the FA concentration that inhibited nitrification in ASBR. In terms of chemical oxygen demand (COD) removal, low removal efficiencies of 17% and 26% were observed in ASBR and GSBR, respectively. The low COD removal efficiencies were associated with the refractory organic content of the leachate used in this study, which resulted in a poor phosphorous removal performance as well. Overall, aerobic granular sludge showed a better performance in removing nutrients and organic matter from young or old landfill leachate, being more efficient than the conventional suspended growth activated sludge. Therefore, the use of AGS for leachate treatment should be encouraged. Further investigations should also be addressed, especially with a focus on improving SND and phosphorus removal efficiencies. / May 2017
102

Analýza inženýrskogeologických a geotechnických poměrů skládky TKO v Úholičkách / Analysis of engineering geological and geotechnical conditions in the MSW landfill Úholičky

Matoušová, Jana January 2013 (has links)
This thesis analyzes the engineering-geological and geotechnical conditions MSW landfills in Úholičky. It includes the methodology of field mapping and documentation work, evaluation of natural conditions the area of interest, the assessment of geotechnical properties of rocks and soils and geotechnical conditions at the landfill and finally deals with risk analysis MSW landfill in Úholičky. At the same thesis includes a search of domestic and foreign literature. The outcome of their work is the engineering map, evaluation and interpretation of the data from the MSW landfill settlement Úholičky. This interpretation has use for further progress of the construction landfill. Powered by TCPDF (www.tcpdf.org)
103

Monitoring and Inverse Dispersion Modeling to Quantify VOCs from MSW Landfill

Das, Sarit Kumar 20 December 2009 (has links)
In USA, the Municipal Solid Waste (MSW) landfills accumulate about 130 million tons of solid waste every year. A significant amount of biodegradable solid waste is converted to landfill gas due to anaerobic stabilization by bacteria. These biochemical reactions produce volatile organic compounds (VOCs) like methane and others. Due to heterogeneity in refuse composition, unpredictable distribution of favorable environmental conditions for bacterial actions and highly uncertain pathway of gases, estimation of landfill gas emission for a particular landfill is complex. However, it is important to quantify landfill gases for health risk assessment and energy recovery purposes. This research is based on the monitoring and modeling methodology proposed by researchers at University of Central Florida is reported in this thesis. River Birch Sub-title D landfill, Westwego, LA was selected as the study area. The total emission calculated using the mathematical model ran on MATLAB is comparable with the result obtained from EPA LandGEM model, using historical waste deposition records
104

Landfill Mining : Institutional challenges for the implementation of resource extraction from waste deposits

Johansson, Nils January 2016 (has links)
The overall aim of the thesis is to examine the institutional conditions for the implementation and emergence of landfill mining. The result shows that  current policy makes it difficult for landfill mining operators to find a market outlet for the exhumed material, which means that landfill mining may result in a waste disposal problem. Regulations also restrict accessibility to the material in landfills. Therefore, it has generally been municipal landfill owners that perform landfill mining operations, which directs learning processes towards solving landfill problems rather than resource recovery. Landfill mining is not, however, necessarily to be perceived as a recycling activity. It could also be understood as a remediation or mining activity. This would result in more favorable institutional conditions for landfill mining in terms of better access to the market and the material in the landfill. The regulatory framework surrounding landfills is based on a perception of landfills as a source of pollution, a problem that should be avoided, capped and closed. Extracting resources from landfills, challenges this perception and therefore results in a mismatch with the regulatory framework. On the other hand, the material in mines is typically regarded in the formal institutions as a positive occurrence. Mining activities are regarded as the backbone of the Swedish economy and therefore receive various forms of political support. This favorable regulatory framework is not available for secondary resource production. Based on the identified institutional conditions, institutional challenges are identified. The core of these challenges is a conflict between the policy goal of increased recycling and a non-toxic environment. Secondary resources are typically punished through strict requirements for marketability, while primary resources are supported through subsidies such as tax exemptions. The authorities lack capacity to manage the emergence of unconventional and complex activities such as landfill mining. The institutional arrangements that are responsible for landfills primarily perceive them as pollution, while the institutions responsible for resources, on the other hand, assume them to be found in the bedrock. The major contribution of the thesis is to go beyond the potential-oriented studies of landfill mining to instead focus on how institutions relate to landfill mining. In order to move towards a resource transition with dominant use of secondary resources a new institutional order is proposed.
105

Municipal regulation of food and waste pickers on landfill sites in South Africa: what should municipalities (dis)allow?

Damon, Lucille Tracy January 2019 (has links)
Magister Legum - LLM / The unemployment rate in South Africa is alarmingly high. In the year 2018, the unemployment rate was recorded at 27.2%. Many people are forced to do desperate, and even dangerous things in order to sustain themselves. This includes people going into landfills to collect recyclable materials to sell and look for a meal. Collecting and retailing recyclable waste has become an informal source of income for thousands of people in South Africa. Waste pickers are individuals whose survival largely depends on collecting, sorting and selling recyclable waste. Waste pickers are defined as people who “collect, sort and sell reusable and recyclable materials”. They embark on waste picking as a means of survival. Given the fact that informal waste management is not regulated by the government, waste pickers are left vulnerable to exploitation and hazardous working environments. Waste pickers are denied access to landfills by either private companies, where municipalities have outsourced this function, or by municipalities themselves. Depending on the management of the landfill, waste pickers could also potentially be faced with crime on landfills with gangsters robbing them of their recyclables and/or hard earned money.
106

Landfills gas emissions and the associated air quality, energy and climate change implications in South Africa

Bhailall, Shaazia January 2016 (has links)
A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. Johannesburg, 2016. / Global methane (CH4) emissions are divided mostly into three sources; biogenic, thermogenic and pyrogenic. The sources can be anthropogenic or natural in origin. Anthropogenic sources include emissions associated with agriculture (rice paddies and ruminants), waste (landfill and waste water), biomass burning and fossil fuels. Landfills have been implicated as one of the largest anthropogenic sources of atmospheric CH4 globally and as a significant contributor to global warming. According to the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report anthropogenic sources account for 304 – 368 TgCH4/year and methanogenesis in landfills and waste contributes between 67 and 90 TgCH4/year to this amount (between 22 and 24% of emissions). / GR2016
107

Íons metálicos (Al, Fe, Mn e Pb) associados a aterros (sanitário e industrial) no município de Tremembé/SP / Metals ions (Al, Fe, Mn and Pb) associate to landfills (domestic and industrial) in the city of Tremembé/SP

Moura, Claudia Lucia de 28 November 2008 (has links)
Um dos grandes problemas das Metrópoles tem sido o descarte de resíduos sólidos. Em diversas situações aterros são selecionados como solução de melhor viabilidade para disposição final desses materiais que, na maioria das vezes, são agentes poluentes. Condições inadequadas de operação e conservação desses locais vêm acarretando inúmeros danos ao meio ambiente, em especial, nas áreas de seu entorno que, muitas vezes, possuem aglomerados residenciais. Neste trabalho foram avaliadas condições ambientais mais significativas de uma área e de seu entorno onde se encontram instalados quatro Aterros, três Sanitários e um Industrial, localizados no Município de Tremembé/SP. Provavelmente como conseqüência do mau gerenciamento e descaso das atividades destes Aterros, eles têm sido alvo de inúmeras denúncias, uma vez que trazem grandes prejuízos à população vizinha. Foram estudados os principais agentes poluidores com especial atenção ao comportamento dos íons metálicos alumínio, ferro, manganês e chumbo, em amostras de diferentes compartimentos - solo, solo/sedimento, sedimento de fundo e águas superficiais e subterrâneas. As águas subterrâneas associadas aos Aterros Sanitários encontram-se comprometidas devido a altas concentrações dos íons estudados, cujo comportamento são, em alguns deles, regidos fundamentalmente pelos valores de pH e potencial óxido-redução. Este fato é motivo de grande preocupação, uma vez que na região a grande maioria da população faz uso de águas para consumo humano extraídas de poços do tipo cacimba, além de regas a hortas, dessedentação de animais e abastecimento de ranários por rios e lago. Os dados analíticos das águas superficiais do Rio Serragem e seu afluente que limitam a área de estudo, também apresentaram valores superiores aos permitidos pelos órgãos oficiais para os íons ferro, alumínio e manganês, sempre ligados aos Aterros. Comprovou-se que as características mineralógicas, granulométricas e capacidade de troca catiônica dos solos associados aos Aterros, não são adequadas para a retenção de íons metálicos. Por outro lado os dados de pH do solo (pH) se mostram favoráveis aos fenômenos de adsorção iônica. A geração de chorume é um dos principais passivos ambientais resultados das atividades dos aterros. No âmbito de sugerir idéias que minimizem os impactos produzidos pelo chorume, este trabalho propôs uma destinação mais apropriada para este efluente. Foram realizados experimentos com chorumes dos três Aterros Sanitários estudados e também com chorume coletados no Município de Santo André e Mauá. O trabalho permitiu afirmar que com a eliminação, por aquecimento, da fração líquida do chorume, resulta em um resíduo que tem seu transporte significativamente facilitado devido à redução em mais de 95% de volume, além de apresentar-se rico em potássio, magnésio, cálcio, fósforo, manganês e ferro e cloretos que podem ser reaproveitado na agricultura, em especial no plantio resistente à teores mais elevados de sódio. / A major problem of big cities have been the disposal of solid wastes. In several situations, landfills are selected as solution of better feasibility for final placement of such material that, in most cases, are pollutants. Inadequate conditions of operation and conservation of those locations are giving rise to numerous damage to the environment, in particular, in the surroundings areas that often have residential clusters. In this work have been assessed the most significant environmental conditions in a particular area and its surroundings where were installed four landfills, three sanitaries and one industrial, located in the city of Tremembé / SP. Probably as a result of bad management and careless of these landfills, they have got many complaints, once is bringing on great damage to neighboring population. Were studied the main pollutants with special attention to the behaviour of metal ions, aluminium, iron, manganese and lead on samples of different compartments - soil, sediment / soil, sediment of surface water and groundwater. Groundwater associated with landfill are involved due to high concentrations of the studied ions, which behaviour are, in some of them, essentially governed by the values of pH and oxide-reduction potential. This fact is a reason of great concern, since in the region the vast majority of the population makes use of water, extract from production well, for human consumption, beyond frog farm. The analytics data of the surface water of Serragem River and its stream limits the study field, also submitted values higher than those allowed by official bodies for ions iron, aluminium and manganese, always related to the landfills. It was proved that the mineral characteristics, size analysis and ability to cationic exchange from associated soils with landfills, are not suitable for the retention of metal ions. In the other hand, the data from pH soil ( pH) are favorable to the phenomena of Ionic adsorption strength. The generation of leachate is one of the main environmental liabilities results of the activities of landfills. With the idea to minimize the impact produced by leachate, this work propose a more appropriate destination for this effluent Were carried out experiments with leachate of three studied landfills and also with collected leachate in Santo André and Mauá cities. This work allowed to affirm that with the disposal, by heating the liquid part of the leachate, results in a residue that has its transport significantly facilitated due to the reduction in more than 95% of its volume, and also it performs rich in potassium, calcium, magnesium, phosphorus, iron, manganese and chlorides that can be reused in agriculture, in particular, plantation resistant to higher levels of sodium.
108

Comportamento de íons chumbo, cobre, níquel e zinco em área de manguezal associado a antigo lixão no Município de Santos - SP / Behavior of lead copper; nickel and zinc ions in magrove area associated with antique landfill in Municipal district of Santos - SP

Fortunato, Janaina Mara 19 August 2009 (has links)
Um dos maiores problemas enfrentados pelas grandes cidades tem sido o gerenciamento de seus resíduos sólidos, principalmente no que tange seu descarte. Condições inadequadas de disposição desses resíduos causam inúmeros danos ao meio ambiente. Em cidades litorâneas é bastante comum a utilização dos manguezais como locais de disposição do lixo, resultando em sua degradação parcial ou mesmo total, levando muitas vezes ao desaparecimento desses ecossistemas. Durante mais de 50 anos a área de manguezal estudada neste trabalho serviu como local de descarte de resíduos provenientes das diversas atividades portuárias sendo utilizada como lixão e mesmo como aterro. Com o objetivo de estudar o comportamento geoquímico de íons de metais pesados chumbo, zinco, cobre e níquel foram analisados e estudados os atributos do solo/sedimento e as águas subterrâneas e superficiais do mar e do Rio Saboó, compartimentos próximos a área de estudos. Através de extrações parciais constatou-se que esses íons encontram-se acima dos valores de Referência de Qualidade da CETESB. O elevado teor de matéria orgânica, característico em área de manguezal, assim como a presença de minerais como illita, de elevado poder adsortivo, foram os principais responsáveis pela fixação iônica apesar das características texturais areno siltosa da área. A presença de íons de metais pesados nas águas subterrâneas e superficiais acima dos Padrões de Referência se deve ao contato do solo/sedimento com soluções com elevados valores de força iônica. Análises químicas do chorume, produto da percolação do antigo lixão, indicaram penas a presença de Pb em quantidades mais elevadas devido, principalmente, ao fenômeno de complexação com a matéria orgânica. / One of the biggest problems big cities are facing is how to manage its solid wastes, especially when we are talking about its disposal. Inadequate condition of its disposal causes many damages to environment. In coast cities are very common the use of mangroves as garbage disposal resulting in its partial or total degradation leading, many times, to ecosystems disappearances. For over 50 years the mangrove site studied in this project was the place of residual disposal from several harbor activities been used as landfill. With the aim to study the geochemistry behavior of ions of hevy metals, such as lead, zinc, copper and nickel, were analysed and studied the attributes of soil/sediment, groundwater and surface water from Saboó river, compartment close to the study field. Through partial extraction was proved that these ions were found above the values from Quality References of CETESB. High content of organic matter, characteristic in mangroves sites, just like the presence of minerals such as illite, which is very adsorptive, were the main responsible from ionic fixation despite the sandy-silty grains size characteristics of the area. The presence of ions in groundwater and superficial waters above the Reference Standarts is due to the contact of soil/sediment with solutions with high values of ionic force. Chemistry analysis of leachate, percolations product of the former landfill, indicated the presence only of Pb in high amount because of complexation phenomenon with the organic matter.
109

Íons metálicos (Al, Fe, Mn e Pb) associados a aterros (sanitário e industrial) no município de Tremembé/SP / Metals ions (Al, Fe, Mn and Pb) associate to landfills (domestic and industrial) in the city of Tremembé/SP

Claudia Lucia de Moura 28 November 2008 (has links)
Um dos grandes problemas das Metrópoles tem sido o descarte de resíduos sólidos. Em diversas situações aterros são selecionados como solução de melhor viabilidade para disposição final desses materiais que, na maioria das vezes, são agentes poluentes. Condições inadequadas de operação e conservação desses locais vêm acarretando inúmeros danos ao meio ambiente, em especial, nas áreas de seu entorno que, muitas vezes, possuem aglomerados residenciais. Neste trabalho foram avaliadas condições ambientais mais significativas de uma área e de seu entorno onde se encontram instalados quatro Aterros, três Sanitários e um Industrial, localizados no Município de Tremembé/SP. Provavelmente como conseqüência do mau gerenciamento e descaso das atividades destes Aterros, eles têm sido alvo de inúmeras denúncias, uma vez que trazem grandes prejuízos à população vizinha. Foram estudados os principais agentes poluidores com especial atenção ao comportamento dos íons metálicos alumínio, ferro, manganês e chumbo, em amostras de diferentes compartimentos - solo, solo/sedimento, sedimento de fundo e águas superficiais e subterrâneas. As águas subterrâneas associadas aos Aterros Sanitários encontram-se comprometidas devido a altas concentrações dos íons estudados, cujo comportamento são, em alguns deles, regidos fundamentalmente pelos valores de pH e potencial óxido-redução. Este fato é motivo de grande preocupação, uma vez que na região a grande maioria da população faz uso de águas para consumo humano extraídas de poços do tipo cacimba, além de regas a hortas, dessedentação de animais e abastecimento de ranários por rios e lago. Os dados analíticos das águas superficiais do Rio Serragem e seu afluente que limitam a área de estudo, também apresentaram valores superiores aos permitidos pelos órgãos oficiais para os íons ferro, alumínio e manganês, sempre ligados aos Aterros. Comprovou-se que as características mineralógicas, granulométricas e capacidade de troca catiônica dos solos associados aos Aterros, não são adequadas para a retenção de íons metálicos. Por outro lado os dados de pH do solo (pH) se mostram favoráveis aos fenômenos de adsorção iônica. A geração de chorume é um dos principais passivos ambientais resultados das atividades dos aterros. No âmbito de sugerir idéias que minimizem os impactos produzidos pelo chorume, este trabalho propôs uma destinação mais apropriada para este efluente. Foram realizados experimentos com chorumes dos três Aterros Sanitários estudados e também com chorume coletados no Município de Santo André e Mauá. O trabalho permitiu afirmar que com a eliminação, por aquecimento, da fração líquida do chorume, resulta em um resíduo que tem seu transporte significativamente facilitado devido à redução em mais de 95% de volume, além de apresentar-se rico em potássio, magnésio, cálcio, fósforo, manganês e ferro e cloretos que podem ser reaproveitado na agricultura, em especial no plantio resistente à teores mais elevados de sódio. / A major problem of big cities have been the disposal of solid wastes. In several situations, landfills are selected as solution of better feasibility for final placement of such material that, in most cases, are pollutants. Inadequate conditions of operation and conservation of those locations are giving rise to numerous damage to the environment, in particular, in the surroundings areas that often have residential clusters. In this work have been assessed the most significant environmental conditions in a particular area and its surroundings where were installed four landfills, three sanitaries and one industrial, located in the city of Tremembé / SP. Probably as a result of bad management and careless of these landfills, they have got many complaints, once is bringing on great damage to neighboring population. Were studied the main pollutants with special attention to the behaviour of metal ions, aluminium, iron, manganese and lead on samples of different compartments - soil, sediment / soil, sediment of surface water and groundwater. Groundwater associated with landfill are involved due to high concentrations of the studied ions, which behaviour are, in some of them, essentially governed by the values of pH and oxide-reduction potential. This fact is a reason of great concern, since in the region the vast majority of the population makes use of water, extract from production well, for human consumption, beyond frog farm. The analytics data of the surface water of Serragem River and its stream limits the study field, also submitted values higher than those allowed by official bodies for ions iron, aluminium and manganese, always related to the landfills. It was proved that the mineral characteristics, size analysis and ability to cationic exchange from associated soils with landfills, are not suitable for the retention of metal ions. In the other hand, the data from pH soil ( pH) are favorable to the phenomena of Ionic adsorption strength. The generation of leachate is one of the main environmental liabilities results of the activities of landfills. With the idea to minimize the impact produced by leachate, this work propose a more appropriate destination for this effluent Were carried out experiments with leachate of three studied landfills and also with collected leachate in Santo André and Mauá cities. This work allowed to affirm that with the disposal, by heating the liquid part of the leachate, results in a residue that has its transport significantly facilitated due to the reduction in more than 95% of its volume, and also it performs rich in potassium, calcium, magnesium, phosphorus, iron, manganese and chlorides that can be reused in agriculture, in particular, plantation resistant to higher levels of sodium.
110

When necessity begets ingenuity: A study of informal waste recycling at Stellenbosch and Bellville, Cape Town

Muller, Monique January 2015 (has links)
Magister Artium - MA / The local economy of the City of Cape Town supported by formal economic activities that are carried out through modern production processes whose existence is officially recognized and benefits from the protection of the authorities, and the informal activities that exist outside official control and protection systems. There is a dynamic connection between actors in the formal sector and those in the informal sector, which is seen at the levels of production, distribution and consumption of goods and services. This research investigates the linkages between informal and formal resource recovery activities in Devon Valley Landfill Site in Stellenbosch and Bellville South Landfill Site in Bellville. The two landfill sites are at the margins on the city economy where the formal and informal sectors interact and at times collide. Notwithstanding the negative health effects associated with the informal waste collections and the fact that informal waste collectors are neglected by policy makers in many developing countries in general and in South Africa in particular, evidence from Southern Africa has shown that the informal sector fosters considerable social, environmental and economic benefits that should be preserved. Informal recyclers constitute the essential workforce of the recycling business. These recyclers have undertaken various commercial and environmental tasks as a survival strategy long before the state and private entities became interested in participating in this profitable business. Waste recycling in most developing countries is a response to the inability of the formal economy to absorb a growing urban population, and the value placed on recyclable materials in the globalized economy. The study explores the various linkages between the informal sector and formal sector in the recycling industry and it examines the activities of these people involved in informal sector activities at the bottom end of the commonly neglected waste recycling chain. It also examines how waste pickers have developed livelihoods based on resource recovery activities at Devon Valley Landfill Site and Bellville South Landfill Site. This thesis is the result of an extensive literature review and primary data collection using a mixed methods approach. Primary sources of information consulted include, waste pickers, dealers, buy-back centres and manufacturing companies. This thesis attempts to establish the respective correlation between urban poverty, informal waste collection, and the recycling industries. The findings reveal that informal recycling is intricately linked to the formal recycling sector with waste pickers selling their waste to merchants and recyclers.

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