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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.
161

Programas municipais de coleta seletiva sem parceria com catadores de materiais recicláveis, no Estado de São Paulo / Municipal Selective Collection Programs without waste pickers organization in São Paulo State.

Reis, Thatiana Costa 28 August 2015 (has links)
Introdução - No Brasil, o Programa Municipal de Coleta Seletiva (PMCS) pode ser executado pelo próprio município, por empresa contratada ou em parceria com uma organização de catadores. Mais de 50 por cento dos PMCS no Estado de São Paulo é realizado por essas organizações. Logo, a maioria dos estudos foca-se nessas organizações, mas os municípios que não possuem parceria também precisam ser estudados. Objetivo - Analisar e avaliar PMCS realizados sem parceria com organização de catadores, na perspectiva de sustentabilidade socioeconômica, ambiental e institucional. Métodos - Para esse estudo, 7 municípios foram selecionados conforme os critérios porte do município e tempo de existência mínima de 2 anos do PMCS, a partir de dados do Sistema Nacional de Informações sobre Saneamento e ligações telefônicas Os municípios estudados foram divididos em pequeno (4) e grande (3) porte. Os responsáveis pelo PMCS foram entrevistados, com base em questionário semiestruturado. Os resultados permitiram caracterizar os PMCS e alimentar 13 indicadores e 2 índices de sustentabilidade de PMCS. Resultados - Foram identificados 4 arranjos institucionais de execução dos PMCS, envolvendo a prefeitura municipal e empresa terceirizada. Os municípios de grande porte apresentam mais indicadores favoráveis à sustentabilidade que os de pequeno porte. A produtividade é maior nos de grande porte, mas a remuneração é melhor nos pequenos. Por outro lado, esses apresentam melhor taxa de recuperação, adesão e atendimento e menor taxa de rejeito, o que eleva o índice de sustentabilidade. Para os 2 índices considerados, os municípios de pequeno porte são mais favoráveis à sustentabilidade que os de grande porte. Conclusões - Os municípios de pequeno porte apresentam maior tendência à sustentabilidade nos indicadores considerados mais importantes num PMCS sem parceria com organizações de catadores. Embora a Política Nacional de Resíduos Sólidos priorize PMCS em parceria com organização de catadores, arranjos sem parceria são possíveis e apresentam-se também sustentáveis na sustentabilidade da valorização de materiais recicláveis. / Introduction - In Brazil, the Municipal Program for Selective Collection (MPSC) can be performed by the municipality itself, by a company contracted or through a partnership with waste pickers organization. More than 50 per cent of the MPSC in São Paulo State is performed by these organizations. Then, most of the studies focuses on these organizations, but the municipalities that dont have partnership also need to be studied. Objective - To analyze and evaluate MPSC performed without partnership with waste pickers organization, through the perspective of socioeconomic, environmental and institutional sustainability. Methods For this study, 7 municipalities were selected according to the criteria: size and minimum time of existence, using data form the National Sanitation Information System and phone calls. The municipalities studied were divided into small (4) and large (3) sizes. The people responsible for MPSC were interviewed, based on a semi-structured questionnaire. The results allowed to characterize the MPSC and feed 13 indicators and 2 MPSC sustainability indexes. Results - Were identified 4 institutional arrangements of MPCS, involving the city government and outsourcing company. The large cities have more favorable indicators of sustainability than the small ones. The productivity is bigger in large municipalities, but the payment (compensation) is better in the small ones. Nevertheless, these present higher recovery rate, adherence and attendance and lower reject rate, what raises the sustainability index. For the 2 index considered the small municipalities are more sustainability favorable than the large ones. Conclusions - Small municipalities are more likely to sustainability for those indicators considered more important in a MPCS without a partnership with waste pickers organizations. Although the National Solid Waste Policy prioritizes MPCS through a partnership with waste pickers organization, arrangements without these kind of partnership are possible and also are sustainable for the recovery of recyclable materials.
162

Combined Electricity Production and Thermally Driven Cooling from Municipal Solid Waste

Udomsri, Seksan January 2011 (has links)
Increasingly intensive efforts are being made to enhance energy systems via augmented introduction of renewable energy along with improved energy efficiency. Resource constraints and sustained high fossil fuel prices have created a new phenomenon in the world market. Enhanced energy security and renewable energy development are currently high on public agenda worldwide for achieving a high standard of welfare for future generations. Biomass and municipal solid waste (MSW) have widely been accepted as important locally-available renewable energy sources offering low carbon dioxide (CO2) emissions. Concerning solid waste management, it has become a critical issue in Southeast Asia since the most popular form for waste disposal still employs open dumping and landfilling. While the need for a complete sustainable energy solution is apparent, solid waste management is also an essential objective, so it makes sense to explore ways in which the two can be joined. Electricity production in combination with energy recovery from flue gases in thermal treatment plants is an integral part of MSW management for many industrialized nations. In Sweden, MSW is considered as an important fuel resource for partially meeting EU environmental targets within cogeneration. However it is normally difficult to justify traditional cogeneration in tropical locations since there is little need for the heat produced. Similarly, MSW-fired cogeneration usually operates with low capacity during non-heating season in Sweden. Therefore, it is very important to find new alternatives for energy applications from waste, such as the implementation of thermally driven cooling processes via absorption cooling in addition to electricity production. The work presented herein concentrates first on an investigation of electricity generation from MSW power plants and various energy applications from waste in tropical urban areas. The potential for various types of absorption chillers driven by MSW power plants for providing both electricity and cooling is of particular interest. Additionally a demonstration and analysis of decentralized thermally driven cooling in district heating network supplied by low temperature heat from a cogeneration of MSW have been conducted. This study aims at developing the best system configuration as well as finding improved system design and control for a combination of district heating and distributed thermally driven cooling. Results show that MSW incineration has the ability to lessen environmental impacts associated with waste disposal, and it can contribute positively towards expanding biomass-based energy production in Southeast Asia. For electricity production, the proposed hybrid dual-fuel (MSW/natural gas) cycles feature attractive electrical efficiency improvements, leading to greenhouse gas emissions reduction. Cogeneration coupled with thermally driven cooling is a solution that holds promise for uniting enhanced sustainability with economic advantages. The system offers great opportunity for primary energy saving, increasing electrical yield and can significantly reduce CO2 emissions per unit of cooling as compared to compression chiller. The demonstration and simulation have also revealed that there is a potential with some modifications and improvements to employ decentralized thermally driven cooling in district heating networks even in temperate regions like Sweden. Thus, expanding cogeneration towards trigeneration can augment the energy supply for summer months in Europe and for year-round cooling in tropical locations. / QC 20110408
163

Organic Acid Production From The Organic Fraction Of Municipal Solid Waste In Leaching Bed Reactors

Dogan, Evrim 01 February 2007 (has links) (PDF)
This study was carried out to evaluate the potential of high-rate anaerobic digestion of high-solids organic fraction of municipal solid waste (OFMSW) for the production of organic acids and alcohols in leaching bed reactors (LBRs). For this purpose, two different experimental set-ups, namely Set-1 and Set-2, were operated. In the Set-1, only OFMSW without paper was studied in two identical LBRs, whereas, four identical LBRs, fed with OFMSW with paper and cow manure in different proportions, were operated in the Set-2. In this study, 50-60% of hydrolysis efficiency was achieved in the LBRs of Set-1, whereas this value was decreased to 20-25% in the LBRs of Set-2 / which was resulted from OFMSW containing cellulose and less volume of water addition in the Set-2. The mass of total volatile fatty acids (tVFA) production was found as 7000-9000 mg at the end of 80 days in the LBRs of Set-1, fed with OFMSW without paper, whereas it was 3000 mg at the end of 40 days in the LBR of Set-2, containing only OFMSW with paper. It was also observed that cow manure addition increased the amount of tVFA production in the LBR of Set-2. In conclusion, LBRs were found as alternative reactors for the degradation of OFMSW compared to completely stirred tank reactors (CSTRs) in terms of rapid hydrolysis and acidification, which can result in high hydrolysis yield and tVFA production.
164

Two-phase Anaerobic Digestion Of Semi-solid Organic Wastes

Dogan, Eylem 01 February 2008 (has links) (PDF)
The objective of this study is to illustrate that phase separation improves the efficiency of an anaerobic system which digests semi-solid organic wastes. Organic fraction of municipal solid waste (OFMSW) was the semi-solid organic waste investigated. In the first part of the study, the optimum operational conditions for acidified reactor were determined by considering the volatile solid (VS) reductions and average acidification percentages at the end of two experimental sets conducted. Organic loading rate (OLR) of 15 g VS/L.day, pH value of 5.5 and hydraulic retention time (HRT) of 2 days were determined to be the optimum operational conditions for the acidification step. Maximum total volatile fatty acid and average acidification percentage were determined as 12405 mg as HAc/L and 28%, respectively in the reactor operated at optimum conditions. In the second part, an acidification reactor was operated at the optimum conditions determined in the first part. The effluents taken from this reactor as well as the waste stock used to feed this reactor were used as substrate in the biochemical methane potential (BMP) test. The results of BMP test revealed that the reactors fed by acidified samples indicated higher total chemical oxygen demand (tCOD) removals (39%), VS reductions (67%) and cumulative gas productions (265 mL). The result of this study indicated that the separation of the reactors could lead efficiency enhancement in the systems providing that effective control was achieved on acidified reactors.
165

Relationship of waste characteristics to the formation of mineral deposits in leachate collection systems

Cardoso, Antonio J 01 June 2005 (has links)
Landfill leachate is generated as a result of reactions between water percolating through the landfill and wastes. Under normal conditions leachate is found at the bottom of landfills and from there, its movement can be controlled with collection systems to be treated, discharged, or recirculated. Landfill leachate collection systems are positioned above the liner and are designed to collect liquid under gravitational flow for the entire active, closure, and post-closure periods. Clogging of any portion of the system can lead to higher hydraulic heads and increase the potential for leakage through the liner. To reduce the quantity of municipal solid wastes (MSW) requiring landfilling, many municipalities have adopted waste-to-energy (WTE) facilities that yield energy in the form of combustible gases and noncombustible residues. Disposal practices for WTE residuals include landfilling in monofills or co-disposal with MSW and other materials such as residues from water and wastewater treatment facilities. There has been concern about co-disposal practices, because the impacts on leachate quality and waste interactions are not well known yet. This research was conducted to evaluate clogging of leachate collection systems due to co-disposal of MSW and combustion residues from WTE facilities. The use of laboratory lysimeters in conjunction with batch tests to predict short-term and long-term leaching characteristics of noncombustible residues from WTE facilities was also evaluated. Laboratory lysimeters were used to simulate monofills (WTE residues and MSW) and co-disposal practices. Relationships between waste composition and leachate quality were evaluated over a seven month period.
166

On the chemistry of combustion and gasification of biomass fuels, peat and waste : environmental aspects

Nordin, Anders January 1993 (has links)
<p>Diss. (sammanfattning) Umeå : Umeå universitet, 1993, härtill 7 uppsatser.</p> / digitalisering@umu
167

RACCOLTA E SMALTIMENTO DEI RIFIUTI SOLIDI URBANI: STIMA DI FUNZIONI DI COSTO IN ITALIA / ESSAYS ON COLLECTION AND DISPOSAL COSTS OF MUNICIPAL SOLID WASTE IN ITALY

ROBU, CRISTINA MANUELA 24 June 2015 (has links)
Questa tesi ha come obiettivo quello di contribuire all'analisi empirica della struttura dei costi del ciclo dei rifiuti solidi urbani in un campione di 534 comuni italiani, per un periodo di sette anni, dal 2004 al 2010. Dopo una panoramica sia delle varie fasi del servizio RSU che del funzionamento del settore in Italia, nel primo capitolo, il secondo analizza la letteratura empirica delle funzioni di costo, con particolare attenzione per i lavori più recenti, tra cui anche i pochissimi italiani sul tema. L’argomento del terzo capitolo riguarda lo studio della presenza di economie di scala e di densità nel settore dei rifiuti utilizzando una specificazione translogaritmica per la funzione di costo stimata con il metodo SUR. L'ultimo capitolo si propone di fornire risposte a domande molto attuali come: la raccolta porta a porta è più costosa? E' meglio smaltire in discarica i rifiuti residui o bruciarli? Data una certa quantità di rifiuti da smaltire, esiste una quantità ottimale da incenerire? Inoltre, dato che molte comunità usano contemporaneamente diversi siti di smaltimento, qual è il numero ottimale di siti per portare i propri rifiuti indifferenziati? / This thesis aims to contribute to the empirical analysis of the cost structure of municipal solid waste management in a sample 534 Italian municipalities, for a period of seven years, from 2004 to 2010. After giving an overview both of the various phases of the MSW service and of the functioning of the sector in Italy in the first chapter, the second chapter reviews the cost function studies, with particular emphasis on recent years including also the very few Italian papers on the topic. This topic of the third chapter the study of the presence of scale and density economies in the Italian waste sector using a translogarithmic specification estimated with the SUR method. The last chapter aims to provide answers to very actual questions as: is the door to door collection more expensive? Is it better to burry residual waste or to incinerate it? Given a certain amount of garbage, is there an optimal quantity to be incinerated? Moreover, given that many communities use contemporaneously different dumpsites, which is the perfect number of disposal sites for unsorted waste?
168

Evaluating the contribution of cooperative sector recycling to the reduction of greenhouse gas emissions: an opportunity for recycling cooperatives in São Paulo to engage in the carbon credit market.

King, Megan Frances 27 April 2012 (has links)
Greenhouse gas emissions can be reduced through recovery and recycling of resources from the municipal solid waste stream. In São Paulo, Brazil, recycling cooperatives play a crucial role in providing recycling services including collection, separation, cleaning, stocking and collective sale of recyclable resources. The present research attempts to measure the greenhouse gas emission reductions achieved by the Cooperpires recycling cooperative, as well as highlight its socio-economic benefits. Methods include participant observation, structured interview, a questionnaire, and greenhouse gas accounting of recycling using a Clean Development Mechanism methodology. The results afford an exploration of the opportunity for Cooperpires and other similar recycling cooperatives to participate in the carbon credit market. / Graduate
169

Βέλτιστη χωροθέτηση μονάδας επεξεργασίας στερεών αστικών αποβλήτων σε συνδυασμό με το χώρο υγειονομικής ταφής υπολειμμάτων

Τσερώνης, Κωνσταντίνος 01 February 2013 (has links)
Χωροθέτηση μονάδας επεξεργασίας ΑΣΑ σε συνδιασμό με τον απαραίτητο ΧΥΤΥ, με μικτό ακέραιο γραμμικό προγραμματισμό, για τη βελτιστοποίηση των ακολουθούμενων διαδρομών των απορριμματοφόρων προς την μονάδα επεξεργασίας και απο την μονάδα προς τον ΧΥΤΥ.Εγινε με εφαρμογή GIS στη Μεσσηνία. / The current thesis is about optimum siting of a MSW treatment plant combined with a landfill for residues based on mixed integer linear programming (MILP) and GIS methodology.
170

Otimização de sistema de roteirização de coleta de resíduos sólidos domiciliares urbanos utilizando ferramentas computacionais. / Optimizing routing of household solid waste collection using computational tools.

Marcus Antonio Ventura 18 March 2013 (has links)
A operação de coleta e transporte de resíduos sólidos urbanos é indispensável dentro de quaisquer sistema de limpeza urbana. É necessário que se intensifique a pesquisa nessa área de conhecimento afim de produzir-se material de auxílio ao poder público municipal e o setor privado. Deste modo o objetivo geral deste trabalho é o estudo da utilização de ferramentas computacionais para a otimização dos roteiros dos serviços de coleta de resíduos sólidos domiciliares. Foi feito um comparativo entre os itinerários percorridos pelos caminhões de coleta quando dimensionados de forma empírica e quando dimensionados com o auxílio de ferramentas computacionais. Verificou-se as vantagens e desvantagens de cada modelo de dimensionamento e o grande potencial de redução de custos quando utilizadas ferramentas computacionais. / The operation of collection and transportation of municipal solid waste is essential within any system of urban sanitation. It is necessary to intensify research in this area of knowledge in order to produce up to aid the municipal government and the private sector material. Thus the objective of this work is to study the use of computational tools for the optimization of routes of solid waste collection services. A comparison between the routes traveled by pickup truck when scaled empirically and when scaled with the aid of computational tools was made. There are advantages and disadvantages of each model sizing and great potential for cost savings when used computational tools.

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