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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.
61

Estudo comparativo de processos de gaseificação de resíduos sólidos urbanos no Brasil. / Sem título em inglês.

Ramires Menezes da Silva Araújo 21 June 2016 (has links)
Os resíduos sólidos urbanos (RSU) no Brasil são na grande maioria direcionados para aterros e lixões a céu aberto, onde ocupam grandes áreas, geram transtornos relacionados ao trafego aéreo, emitem gases responsáveis pelo efeito estufa sem o devido reaproveitamento energético. Como alternativa para a minimização do passivo ambiental causado pelos RSUs e potencial reaproveitamento energético propõe-se um estudo comparativo de processos de gaseificação desses resíduos em diferentes meios gaseificantes. A modelagem e simulação dos processos foram feitas aplicando-se o método de minimização da energia livre de Gibbs não estequiométrica. Considerou-se a quantidade de resíduo sólido urbano destinado da sub-região de Campo Limpo - São Paulo - e a sua composição representativa expressa pelo método ultimate-analysis. O processo de gaseificação foi implementado em simulador de processo e o estudo se concentrou nas etapas do processo de gaseificação, investigando-se a ação dos seguintes meios gaseificantes: ar, vapor e mistura ar e vapor. Os principais resultados analisados foram a composição do produto da gaseificação e o potencial energético do produto. / The major destiny of Municipal Solid Waste (MSW) in Brazil is landfill. These sites occupy large areas; most of them are open, being simply disposal areas. This situation causes several problems ranging from greenhouse gases to air traffic jeopardizing. The use of MSW in energy generation addresses these problems, once it is one of most promising solutions to MSW treatment. This work is the study of gasification from the energy potential. It was carried out through minimization of Gibbs energy in a process simulator. The MSW considered was the one from area of Campo Limpo in São Paulo city. Its composition was expressed by ultimate analysis. The use of different gasification agents included air, steam and their mixtures was analyzed. The results were HHV and composition of generated gases.
62

ASTM D5231 aplicada à caracterização da composição gravimétrica dos resíduos sólidos urbanos : estudo de caso : Novo Hamburgo, RS

Waskow, Régis Pereira January 2015 (has links)
O presente trabalho avaliou a composição gravimétrica dos resíduos sólidos urbanos (RSU) do município de Novo Hamburgo-RS. Foram realizadas 10 amostragens de diferentes setores de coleta ao longo dos meses de março e abril de 2014. Juntamente com a análise da composição gravimétrica foi avaliada a densidade dos RSU de Novo Hamburgo. No mesmo período foram realizadas amostragens da saída das esteiras de triagem da central de transbordo do município, com um total de 5 amostras. Os procedimentos amostrais seguiram a norma americana ASTM D5231/2008. A composição gravimétrica obtida para os RSU corresponde em: 57,13% matéria orgânica; 14,82% plástico; 12,69% papel; 4,34 têxtil; 1,62% metais ferrosos; 0,69% borracha; 0,49% metais não ferrosos; 0,40% couro; 0,35% madeira e 3,86% outros. O valor médio para a densidade do RSU encontrado foi de 173 kg/m³. Alguns resíduos encontrados como eletroeletrônicos, pilhas e baterias, embalagens contaminadas com óleo, alguns resíduos sólidos industriais (RSI) e outros, não deveriam ser destinados junto aos RSU. A maior fração da matéria orgânica era esperada visto que este comportamento é identificado na composição gravimétrica média dos RSU do Brasil. Os resultados demonstram um potencial para implantação do processo de compostagem pelo alto potencial de resíduos orgânicos, sendo necessário mais análises para garantir a qualidade e aplicabilidade do composto. O descarte inadequado de resíduos orgânicos e recicláveis juntos inviabiliza a reciclagem, aumentando as quantidades destinadas ao aterro sanitário. A composição gravimétrica obtida para a saída das esteiras de triagem corresponde em: 81,60% matéria orgânica; 8,63% plástico; 2,89% papel; 1,66 têxtil; 0,58% borracha; 0,52% metais ferrosos; 0,37% metais não ferrosos; 0,35% madeira; 0,23% couro e 1,81% outros. Foi identificada uma grande presença de materiais recicláveis na saída das esteiras de triagem. Ações foram propostas para aumentar a eficiência do processo de triagem e melhorar o aproveitamento dos recicláveis. Políticas públicas foram sugeridas visando à melhoria dos processos de gestão dos RSU do município. Os resultados obtidos são representativos para o período avaliado, sendo passíveis de alteração quando de amostragem em outros períodos. / The purpose of this paper is evaluate the gravimetric composition of Municipal Solid Waste (MSW) of Novo Hamburgo - RS. Ten samples were collected in different areas between March to April 2014 according to ASTM D5231/2008. Simultaneously were evaluated the MSW density and the materials collection after sorting followed the ASTM D5231/2008. The gravimetric composition of MSW consists in 57,13% of organic matter; 14,82% of plastic; 12,69% of paper; 4,34% of textile; 1,62% of ferrous metals; 0,69% of rubber; 0,49% of noun ferrous metals; 0,40% of leather; 0,35% of wood and 3,86% of others. The MSW density were 173 kg/m³. Some residues as electronics, batteries, oil contaminated packaging and some industrial solid waste should not be disposed as MSW. A larger fraction of organic matter was expected as shown in the most Brazilian analyzed papers since that behavior is known about the gravimetric average composition of MSW in Brazil. The results demonstrate the potential implementation of the composting process considering the amount of organics, requiring further analysis to ensure the quality and applicability of the produced compounds. The inappropriate disposal of organic matter and recyclables together turn unfeasible the recycling. The gravimetric composition of material after sorting consists in: 81,60% of organic matter; 8,63% of plastic; 2,89% of paper; 1,66 of textile; 0,58% of rubber; 0,52% of ferrous metals; 0,37% of non ferrous metals; 0,35% of wood; 0,23% of leather e 1,81% of others. Amounts of recyclables was identified after sorting and based on this evidence actions were proposed to increase the sorting process efficiency and improve the recycling. Public policies were recommended to enhance the MSW management. The results are representative considering this measuring period, which could change if realized in another periods.
63

Análise da composição gravimétrica dos Resíduos Sólidos Urbanos (RSU) da região de Santa Maria, pré e pós-triagem / Gravimetric composition analysis of municipal solid waste from Santa Maria region, pré and post separation process

Habitzreuter, Milena Tomasi January 2008 (has links)
Neste trabalho foi estudada a caracterização gravimétrica dos resíduos sólidos da macroregião de Santa Maria (RS). A região estudada é composta pelos municípios de Júlio de Castilho, São Pedro, e pela região da Quarta Colônia, que por sua vez engloba os municípios de Faxinal do Soturno, Nova Palma, São João do Polêsine, Agudo, Paraíso do Sul e Dona Francisca. Os ensaios de caracterização gravimétrica foram realizados na Unidade de Triagem de Paraíso do Sul, município vizinho à Santa Maria no período entre julho e setembro de 2007. Avaliou-se a composição do resíduo in natura e após a triagem de material reciclável e orgânico para que fosse possível analisar a eficiência da triagem e estudar algumas características físicas do rejeito (resíduo sem as porções orgânica e reciclável). A massa de resíduos sólidos urbanos da macro-região de Santa Maria é bastante heterogênea e apresenta variações de acordo com as características sócio-econômicas das regiões. Os resultados da caracterização gravimétrica dos resíduos urbanos mostraram uma significativa influência de fatores externos, tais como a presença de umidade devido ao nível pluviométrico e a ação dos ventos. Isto é devido ao fato que materiais como papel e papelão são descaracterizados em presença de umidade e misturam-se às porções de rejeito e matéria orgânica. A realização da caracterização gravimétrica pré e pós-triagem permitiu uma análise da eficiência da caracterização (ou triagem) feita pela esteira e a verificação do potencial de aproveitamento dos resíduos. A média dos dados analisados indica uma eficiência de cerca de 86 % na triagem efetuada pela esteira, sendo que grande parte do material mal caracterizado é matéria orgânica, um material difícil de ser triado e que muitas vezes incorpora-se a outros materiais. O resíduo da região de Santa Maria apresenta um potencial de aproveitamento de 62 %, seja com a triagem de recicláveis, seja com a compostagem da matéria orgânica. Foi feito um ensaio de compactação no material de rejeito da esteira, o qual foi compactado em prensa estática com uma pressão equivalente de 250 kPa, obtendo-se um fardo com densidade de 7, 66 kN/m3 (ou cerca de 750 kgf/ m3). Este fardo de rejeito apresentou uma consistência firme que permitiu seu manuseio sem necessidade de reforços, mas seu elevado peso dificultou as operações de transporte. Este rejeito compactado não tinha uma significativa quantidade de material orgânico, e por isso, a compactação não gerou líquido (chorume) em quantidade significativa. A compactação do rejeito proporcionou uma redução volumétrica da ordem de 3,2 vezes. / On this work the gravimetric composition of solid wastes from Santa Maria (RS) region was studied. The region is composed by the towns of Júlio de Castilho and São Pedro and by the so-called Quarta Colônia, composed by Faxinal do Soturno, Nova Palma, São João do Polêsine, Agudo, Paraíso do Sul e Dona Francisca towns. The tests were carried out at the Separation Unity of Paraíso do Sul, close to Santa Maria town, which receive the municipal waste of the region. The gravimetric characterization tests were carried out from July to September 2007. The composition of the waste was determined just after arrival and also after the separation of organic matter and recyclables, in order to study the efficiency of the separation process and analyze some physical characteristics of the waste with and without these components. The municipal solid wastes from Santa Maria region is heterogeneous and presents variations which are related to socio-economic characteristics of the regions which originated them. The results of gravimetric characterization showed a significant influence of the external factors, such as the presence of humidity, due to rains, and the wind. This is due to the fact that materials like cardboard and normal paper loose their characteristics and aspect in presence of water, getting mixed up with the refuse and organic matter. The characterization carried out pre and post separation of recyclables allowed to examine the efficiency of the separation which is done on the mat and also to make an analysis of the potential of waste reuse. The data average indicates an efficiency of around 86% in the separation process on the mat, being organic matter a large part of the material wrongly classified as refuse, as it is a difficult material to select from the waste and one which easily incorporates into others. The waste from Santa Maria region has a potential of 62% of being reused or through recycling or by composting (organic matter). A compaction test was carried out on the refusal of the mat. The material was compacted statically on a frame with an equivalent pressure of 250 kPa. A block of refuse with unity weight of 7.66 kN/m3 was obtained. This block had a firm consistency and did not require reinforcing to be moved around, but its large weight imposed some difficulties. The refuse had little quantity of organic matter and so the test did not generate significant amount of liquid. The refuse compaction generated a volumetric reduction of 3.2 times.
64

Gestão de resíduos sólidos urbanos no município de Porto da Folha-SE / Urban solid waste management in the municipality of Porto da Folha-SE

Santos, Anne Grazielle Costa 15 February 2012 (has links)
The solid waste production is entirely linked to economic development and population, however, the development doesn t recognize limits, happens disorderly significant indices contributing pollution and environmental degradation. The economic model exercised since the Industrial Revolution with the disconnect of the growth of cities and the health infrastructure has enabled new sources of secular problems spreading into the environment. Among them, the solid waste configures an aggravating faced by society by involving aspects of political, social, economic, environmental and public health. In Brazil, the absence of supervision and of propositions for implementation of solid waste management resulting in poor living conditions in the poorest regions mainly. The goal of this research was to make a diagnosis of municipal solid waste management in the municipality of Porto da Folha/SE thus wished to describe the characteristics of municipal solid waste management home; evaluate the social and environmental risks resulting from inadequate management and determine the composition of the waste produced in the city. The hypothesis of question assumed that the inefficiency of urban solid waste management anticipated hiring cleaning agents and the availability of adequate facilities, while the lack of supervision and universalization of services imply social and environmental risks. The survey has a qualitative character, however the data analysis are held of interdisciplinary problem quantitatively. The methodology was divided into: bibliographical, characterization of the area under study, instruments for data collection and waste characterisation. Porto da Folha has a municipal population of 27,146 inhabitants, the municipality is bordered on the North by the State of Alagoas, in the East with Gararu West with Poço Redondo and South with the municipalities of Nossa Senhora da Glória and Monte Alegre the Sergipe. Upon completion of this study it was found that the city has urban cleaning system through the services of sweeping, collecting and transporting waste, however this system presented managerial difficulties arising from territorial distances, costs and expenditure for personnel and equipment, soas proposition suggested the Waste Management Plan that meets all of the municipality. / A produção de resíduos sólidos está inteiramente ligadaao desenvolvimento econômico e populacional, no entanto esse desenvolvimento não reconhece limites, acontece desordenadamente contribuindo para índices significativos de poluição e degradação ambiental.O modelo econômico exercido desde a Revolução Industrial com o descompasso do crescimento das cidades e a infraestrutura sanitária permitiram novas fontes de propagação aos problemas seculares no meio ambiente. Entre eles, os resíduos sólidos configuram-se como um agravante enfrentado pela sociedade por envolver aspectos políticos, sociais, econômicos, ambientais e de saúde pública.No Brasil, a fiscalização precáriae a ausência de proposições para implementação da gestãode resíduos sólidos resultam em condições de vidade baixa qualidade, principalmente nas regiões mais pobres. O objetivo desta pesquisa foi realizar um diagnóstico da Gestão dos Resíduos Sólidos Urbanos do município de Porto da Folha/SE, dessa forma, pretendeu-se descrever as características do gerenciamento dos resíduos sólidos urbanos domiciliares; avaliar os riscos socioambientais decorrentes do manejo inadequado e determinar a composição dos resíduos produzidos na cidade.No desenvolvimento desta pesquisa pressupôs como hipótese que a ineficiência do gerenciamento dos resíduos sólidos urbanos precedea contratação de agentes de limpeza e a disponibilidade de equipamentos adequados, enquanto que a falta de fiscalização e universalização dos serviços implicam em riscos socioambientais. A pesquisa possui caráter qualitativo, contudo a análise de dados realizou-se quantitativamente, permitindo uma visão interdisciplinar da problemática. A metodologia foi dividida em: levantamento bibliográfico, caracterização da área em estudo, instrumentos para coleta de dados e a caracterização dos resíduos. Porto da Folha possui uma população municipal de 27.146 habitantes,o município limita-se ao norte com o Estado de Alagoas, a leste com Gararu, a oeste com Poço Redondoe Sul com os municípios de Nossa Senhora da Glória e Monte Alegre de Sergipe. Na conclusão deste estudo verificou-se que o município possui sistema de limpeza urbana através dos serviços de varrição, coleta e transporte de resíduos. Entretanto esse sistema apresentou dificuldades gerenciais decorrentes das distâncias territoriais, custos e dispêndio depessoal e de equipamentos, portanto como proposição sugeriu-se o Plano de Gerenciamento de Resíduos que atenda todo o município.
65

Aproveitamento energético dos resíduos sólidos urbanos : desafios e tecnologias

Vieira, Anne Caroline Almeida 14 February 2011 (has links)
This dissertation aims to evaluate the energy use of household waste by considering the various existing technologies. The achievement of this study was made possible by the bibliography of studies relevant to the topic to the theme in focus, and from them were chosen technologies Incineration, Waste Gas and Anaerobic Digestion, used for energy recovery of municipal solid waste. A powerful convergence of interests mentioned above are the sustainability indicators that provide a diagnosis of reality, able to spot trends and possible solutions to the problems faced. From the sustainability indicators, we can define what technology provides a better trend toward sustainability through economic, social, political, cultural and environmental. Shortly before the scenario in which Brazil is presented, we can see that regardless of the technology employed, the environmental, social and economic development is still the biggest destination of illegal waste. Therefore, this study suggested sustainability indicators that contribute to choosing the most appropriate technology for power generation as well as subsidies for the development and implementation of public policies by managers for sustainable development. / Esta dissertação tem como objetivo avaliar o aproveitamento energético dos resíduos domésticos considerando as diversas tecnologias existentes. A consecução do presente estudo foi possível mediante o levantamento bibliográfico de estudos realizados ao tema pertinente à temática em foco e, a partir dos mesmos, foram escolhidas as tecnologias Incineração, Gás de Lixo e Digestão Anaeróbia, utilizadas para o aproveitamento energético dos resíduos sólidos urbanos. Uma ferramenta poderosa de convergência dos interesses acima mencionados são os indicadores de sustentabilidade que fornecem um diagnóstico da realidade, capazes de sinalizar tendências e possíveis soluções para os problemas enfrentados. A partir dos indicadores de sustentabilidade, pode-se definir qual tecnologia proporciona uma melhor tendência à sustentabilidade através das dimensões econômica, social, política, cultural e ambiental. Logo, neste trabalho foram sugeridos indicadores de sustentabilidade que contribuem para a escolha da tecnologia mais apropriada para a geração de energia, bem como subsídios para a elaboração e implantação de políticas públicas por parte dos gestores visando o desenvolvimento sustentável.
66

Percepção de lixo da população de Manaus (AM): a problemática da reciclagem

Silva, Wanderlei Pires da 19 September 2008 (has links)
Made available in DSpace on 2015-04-11T13:54:57Z (GMT). No. of bitstreams: 1 Dissertacao Wanderlei Pires da Silva.pdf: 2987112 bytes, checksum: 949d7d9c015542bede48e81ae311af9f (MD5) Previous issue date: 2008-09-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Since the Manaus Free Trade Zone creation in 1967 the solid wastes become serious problem in whole urban Manaus City. In 2002, the generation of per capita Municipal Solid Waste (MSW) in Manaus was 1 kg/inhabit./day in average, representing a production of 1,300 t/day. The objectives this present work were i) evaluating the Manaus inhabitant perception on the MSW and the recycling, ii) characterizing the current form of MSW management applied, and iii) proposing a alternative program for MSW managing for town hall of the Manaus. Structured questionnaires were applied in six Manaus geographical zones in which the inhabitants answered on socioeconomic, MSW problems, recycling several aspects, separate collection questions. Findings showed that the Manaus town hall public politics have been completely deficient for solving the MSW problems. However, the results also revealed Manaus inhabitants having a good perception on MSW problems. The respondents were agreed with the implantation of an alternative MSW management including separate collection. / A partir da criação da Zona Franca de Manaus, em 1967, os resíduos sólidos urbanos se tornaram um sério problema em toda a área urbana da cidade de Manaus. Em 2002, a geração de RSU per capita em Manaus era de 1 kg/hab./dia, em média, o que significava uma produção de 1.300 t/dia. Os objetivos do presente trabalho foram: i) avaliar a percepção sobre RSU e reciclagem dos habitantes de Manaus, ii) caracterizar a forma atual de manejo dos RSU praticada e iii) propor um programa alternativo para o gerenciamento de RSU no município de Manaus. Questionários estruturados foram aplicados em seis zonas geográficas de Manaus, nos quais os habitantes responderam sobre questões sócio-economicas, problemas de RSU, vários aspectos da reciclagem e coleta seletiva. Os resultados mostraram que as políticas públicas do município de Manaus tem sido completamente deficientes para resolver o problema dos RSU. Entretanto, os resultados reveleram também que os habitants de Manaus têm boa percepção sobre os problemas de RSU. Os entrevistados se mostraram receptivos à implantação de um programa alternativo de gerenciamento de RSU, incluindo coleta seletiva.
67

The Effects of Ammonia on Anaerobic Digestion of the Organic Fraction of Municipal Solid Wastes

Akindele, Akinwumi January 2016 (has links)
The effect of ammonia on anaerobic digestion of the organic fraction of municipal solid wastes (OFMSW) was investigated in this study. This study involved two sets of experiments. First set involved the investigation of ammonia toxicity on AD of synthetic OFMSW only (SW), at three different phases and pH 7.5, 8.0 and 8.5. Phase 1 was the Batch Methane Potential (BMP) phase. BMP tests were conducted under ammonia concentration of 2500 mg/L, 5000 mg/L, 7500 mg/L and 10,000 mg/L and at pH 7.5, 8.0, and 8.5, using 500 mL Kimax® glass bottles. The total working volume of the mixture was 300 mL comprising 120 mL of mesophilic anaerobically digested inoculums, 30 g of OFMSW, various TAN concentrations ranging from 2,500, 5,000, 7,500 to 10,000 mg/L, and equal portions of buffer in form of NaHCO3 and KHCO3. The second phase of the experiment examined whether the tolerance of the bacteria to high ammonia concentration would improve by acclimating the microbes to high ammonia concentrations, through gradual TAN loading. TAN concentration was increased gradually at pH 7.5, 8.0 and 8.5 weekly. The third phase of the experiment was Semi-continuous batch phase. This phase examined the possibility of reducing the inhibitory effect of ammonia on AD, batch reactors at pH values of 8.0 and 8.5 containing initial TAN concentrations of 7500 mg/L and 10,000 mg/L. 3 g of the digestate containing high ammonia concentration(s) was replaced with fresh substrate at every 4 days, 7 days and 15 days. The second set of experiment involved study of the effects of ammonia on anaerobic digestion of OFMSW with real landfill leachate (SW+L). Phase 1 was BMP in which the effect of ammonia was examined at TAN concentrations of 7,500 and 10,000 mg/L. The phase 2 of the (SW+L) gradual TAN TAN loading. The possibility of adapting mesophilic bacteria to high ammonia concentration was examined. The results of the study confirmed that ammonia is toxic to AD, at high concentrations. Biogas production reduced with increase in TAN concentration. Reduction in Cumulative Biogas Production (CBP) compared with control reactors was as much as 43 %, 64 % and 77 % in reactors containing 7500 mg/L TAN at pH 7.5, pH 8.0 and pH 8.5. CBP reduced to 80-85 % in reactors containing 10,000 mg/L TAN across the pH examined. Also, replacing 3g of digestate containing high TAN concentrations of 7500 mg/L and 10,000 mg/L with 3 g fresh substrate improved the activity of the mesophilic bacteria as seen in the surges in biogas production when fresh substrate was injected into the reactors. Similar results were obtained on effect of ammonia on AD of OFMSW mixed with real landfill leachate to simulate an anaerobic bioreactor landfill. CBP reduced as the TAN concentration increased. Compared with control reactors, reactors containing 7500 mg/L TAN at pH 8.0 and pH 8.5 had 61 % and 80 % reduction in CBP. Likewise, reactors containing 10,000 mg/L TAN at pH 8.0 and pH 8.5 had 68 % and 85 % reduction in CBP, compared with control reactors. Study confirmed that pH influenced the toxicity and composition of Total Ammonia Nitrogen (TAN). At high pH (i.e. 8.5), FAN component of TAN was about 26 % and was inhibitory to the methanogens. Results also showed that mesophilic bacteria could be adapted to a TAN concentration of about 5000 mg/L at pH 7.5 through gradual TAN loading. Similar results were obtained on effect of ammonia on AD of OFMSW mixed with real landfill leachate to simulate an anaerobic bioreactor landfill. CBP reduced as the TAN concentration increased. Compared with control reactors, reactors containing 7500 mg/L TAN at pH 8.0 and pH 8.5 had 61 % and 80 % reduction in CBP. Likewise, reactors containing 10,000 mg/L TAN at pH 8.0 and pH 8.5 had 68 % and 85 % reduction in CBP, compared with control reactors. Study confirmed that pH influenced the toxicity and composition of Total Ammonia Nitrogen (TAN). At high pH (i.e. 8.5), FAN component of TAN was about 26 % and was inhibitory to the methanogens. Results also showed that mesophilic bacteria could be adapted to a TAN concentration of about 5000 mg/L at pH 7.5 through gradual TAN loading.
68

Influence of socio-economic factors on municipal solid waste generation / Vliv socio-ekonomických faktorů na produkci komunálního odpadu

Kováčová, Alena January 2010 (has links)
Diploma thesis examines the relationship between socio-demographic trends and municipal solid waste generation. It follows an increasing trend towards the integration of environmental, economic and social aspects to indicate the municipal solid waste generation at the present time. Not only gross domestic product, but also social indicators, household size and age structure have a significant impact on the amount of municipal solid waste. The topical aim of the thesis is to review the state of present knowledge regarding socio-demographic changes, analyse previously published models of municipal waste generation, identify socio-economic factors important for describing the amount of municipal waste at various levels in Czech Republic and observe broad scale of potential relationships. The observations and survey were made on two levels -- regional and city level. From the models obtained by working with various set of explanatory variables at regional level, one linear multivariate regression model with explanatorz power 90,20% was described in diploma thesis. It consists of one dependent variable -- municipal waste generation per household and five independent variables (net money income, household size, living costs per household per month, number of retired pensioners in household and households with net income below minimum subsistence). At city level, some parameters were just proved by correlation analysis, but they were not used as explanatory variables in regression analysis in order to obtain optimal model. Those used in regression analysis are number of inhabitants and number of people in main age groups. Regression index R2 indicates that this model explains 58,78% of the variability in total household waste generated in cities. To conclude, socio-demographic determinants of environmental protection are usually less relevant for explanation of fluctuations within waste management chain than psychological variables (attitudes, values, beliefs) and political factors. Anyway, literature review indicates that the investigations and assessment of future municipal waste streams should cover not only commonly used economic parameters, but also socio-demographic factors (Bach, 2003; Beigl, 2004; Řeháková, 2001).
69

Optimisation d’un procédé à deux étapes pour la production d’un mélange hydrogène/méthane (biohythane) à partir de la fraction fermentescible des ordures ménagères / Optimization of a two-step process for generating a mixture of hydrogen/methane (biohythane) using organic fraction of municipal solid waste

Paillet, Florian 09 November 2017 (has links)
La valorisation de la fraction organique des déchets ménagers par un procédé biologique à deux étapes permet la production d’un mélange H2/CH4 comprenant 5 à 20% d’hydrogène appelé plus communément biohythaneLa première étape consiste en un réacteur de fermentation sombre (hydolyse/acidogénèse) où une partie de la matière organique est dégradée en H2 et en molécules simples (acides gras volatils, sucres simples, éthanol...). Les déchets prédigérés provenant du réacteur de fermentation peuvent ensuite être utilisés dans un réacteur de méthanisation afin de finaliser la dégradation de la matière organique pour produire du méthane. Cependant, seule une efficacité optimale de l’étape de fermentation sombre permet au procédé d’être économiquement viable comparé à un méthaniseur simple. Cette thèse a donc pour objectif d’améliorer la compréhension du système de fermentation sombre afin d’optimiser le rendement de conversion en hydrogène et en autres métabolites produits. Les expériences menées en réacteurs batch ont permis de mettre en évidence les limites ainsi que les conditions opératoires optimales influençant le rendement en hydrogène. Il a également été montré que la fermentation sombre possède une grande stabilité et robustesse lors de la recirculation de l’effluent pour des batchs successifs. Enfin, différentes échelles de réacteurs ont été réalisées pour se rapprocher des conditions réalisables à l’échelle industrielle. Cette thèse apporte de nouvelles informations et une compréhension poussée du procédé de fermentation sombre pour à terme, envisager la création d’un procédé industriel à deux étapes pour la production de biohythane à partir de déchets ménagers. / Two-step process producing biologically a mixture of H2/CH4 (5-20 % of H2) so called biohythane can be used for organic fraction of municipal solid waste valorization (OFMSW). The first step consists of a dark fermentation reactor (hydolysis/acidogenesis) which allows a partial degradation of organic matter into H2 and simple molecules (volatile fatty acid, sugar, ethanol…). Then the outlet of the first reactor can be used in a second reactor for methane production ending organic matter degradation. However, only high efficiency of the dark fermentation step allows making this two-step process economically viable compared to a simple anaerobic digestion reactor. The aim of this thesis is to improve the knowledge of the dark fermentation process for optimizing hydrogen and metabolites productions. Experiments were achieved to better understanding the main factors limiting hydrogen production along with the operational conditions that could improve hydrogen yield. This thesis also shows the high stability and robustness of effluent recirculation for consecutive hydrogen batch reactor. Finally, several sizes of reactors were performed for a scale-up of the process in order to reach the real operational conditions in industrial scale. This thesis provides new knowledge of the dark fermentation process in mixed culture for creating an industrial two-step process for biohythane production using municipal solid waste.
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Analýza složení komunálních odpadů / Analysis of Municipal Solid Waste Composition

Novák, Michal January 2019 (has links)
This diploma thesis provides extensive research of municipal solid waste studies and methodologies from all over the world. Firstly, the studies are described in general and then divided into several groups depending on the principle of their working practices, including their advantages and disadvantages. Secondly, the studies are divided by geographic areas. The results of the individual studies are presented and compared. Based on the findings in the thesis, appropriate methodology for municipal solid waste analysis in the Czech Republic is proposed.

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