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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

Contribution à l'élaboration d'un procédé de valorisation des cendres volantes et des résidus d'épuration des fumées d'incinération d'ordures ménagères / Valorisation of municipal solid waste incineration fly ashes and air pollution control residues

De Boom, Aurore 04 November 2009 (has links)
D’après les limites d’acceptation pour la mise en décharge des déchets, les REFIOM (Résidus d’Epuration des Fumées d’Incinération d’Ordures Ménagères) sont considérés comme déchets dangereux, car ils libèrent des quantités importantes de chlorures et de métaux lourds lorsqu’ils entrent en contact avec de l’eau. Ces solides doivent par conséquent être traités avant leur mise en décharge. A côté des traitements visant l’acceptabilité des REFIOM en décharge, quelques recherches entrevoient la possibilité de valoriser ces résidus, notamment dans des matériaux cimentaires. <p>Les recherches présentées ici s’inscrivent dans cette tendance nouvelle et visent l’élaboration d’un procédé combinant traitement et valorisation des REFIOM. <p>Les REFIOM représentent en fait différents types de résidus provenant des installations que rencontrent les fumées issues de l’incinération des déchets. La composition des résidus diffère selon leur origine. Il est dès lors apparu essentiel de considérer chaque type de résidu séparément et de poursuivre l’élaboration d’un traitement sur un seul type de REFIOM. Nous avons choisi de concentrer les recherches sur les Cendres Volantes de Chaudière (CVC), ces résidus se retrouvant dans tout incinérateur. <p>Le traitement des CVC est basé sur l’extraction de fractions valorisables et la séparation de fractions contaminées, permettant d’obtenir des résidus acceptables en décharge ou, idéalement eux-mêmes valorisables. <p>Une séparation magnétique permet d’extraire environ 10% en poids des CVC mais ne semble pas exploitable dans le cadre du traitement des CVC car les particules magnétiques contiennent des impuretés (composés non magnétiques) et que le résidu final reste contaminé. <p>Une étude de la répartition des éléments en fonction de la taille des particules (granulochimie) est effectuée sur les CVC. Il apparaît intéressant de séparer la fraction inférieure à 38 µm obtenue lors d’une séparation granulométrique, effectuée en voie humide en utilisant une solution dense. En effet, cette fraction semble être nettement plus contaminée en Pb (soluble) que le reste des CVC. Une telle séparation constitue dès lors la première étape du traitement des CVC. Elle est suivie par des étapes de lavage des fractions obtenues, visant à extraire les sels solubles (chlorures et métaux). Les lavages sont envisagés à contre-courant afin d’utiliser au mieux l’eau de lavage. Une recirculation interne des solutions est également prévue, de sorte que, théoriquement, le procédé ne génère pas d’effluents liquides. Une étape de précipitation de composés métalliques (PbS dans ce cas-ci) est prévue après le lavage des boues. <p>Le procédé de traitement des CVC produirait ainsi des boues et des granulats décontaminés, des sels et des précipités métalliques. Seules certaines étapes du procédé ont été investiguées en laboratoire ;des essais supplémentaires sont encore nécessaires pour optimiser chaque étape, comprendre les phénomènes physico-chimiques qui se produisent et assurer des filières de valorisation. <p>/<p>Municipal Solid Waste Incineration (MSWI) fly ashes and Air Pollution Control (APC) residues are considered as hazardous waste according to the limits for the acceptance of waste at landfills, because high amounts of chlorides and heavy metals leach from the solids when those are in contact with water. These residues have thus to be treated before they can be accepted in landfill. Several treatments aim to limit the leaching of the residues. Beside these treatments, some research works go further the treatment and consider the valorisation of MSWI fly ashes and APC residues, e.a. in cementitious materials. <p>The present work follows the new trend and aims to build up a process that combines treatment and valorisation of MSWI fly ashes and APC residues. <p>MSWI fly ashes and APC residues come from the devices encountered by the flue gases from waste incineration. The residues composition differs according to their origin. It seems thus essential to consider each type of residues separately and to develop the treatment only on one sort of residue. Boiler Fly Ashes (BFA) were chosen because they exist in every modern MSWI plant. <p>The BFA treatment is based on the extraction of valorisable fractions and on the separation of contaminated fractions, which makes the final residues less hazardous; these final residues would then be acceptable in landfill, or, even better, be valorisable. <p>A magnetic sorting extracts ~10% (wt.) of BFA; however, such a separation would not be useful in a treatment process because the magnetic particles contain some impurities (non magnetic particles) and the final residue is still hazardous. <p>The repartition of the elements according to the particles size has been studied on BFA. It seems interesting to separate the BFA at 38 µm by a wet sieving process using a dense solution. The lower fraction presents a higher contamination in Pb (soluble) than the larger. Consequently, the first step of the BFA treatment consists of a wet sieving. Washing steps follow the sieving and aim to extract soluble salts (chlorides, heavy metals). These washings work in a counter-current way to optimise the use of water. The solutions are recycled in the process, which implies the absence of liquid effluents. A precipitation step of some metallic compounds (PbS in this case) is foreseen after the washing of the lower fraction. <p>The BFA treatment process would produce decontaminated sludge and coarse fractions, salts and metallic compounds. Some steps of the process have been investigated at lab-scale; further studies are necessary to optimise each step, to understand the observed reactions and to guarantee valorisation channels. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished
162

Absorpční oběhy v teplárenství / Absorption cycle in the heating industry

Pleva, Ondřej January 2019 (has links)
Goal of this thesis is to introduce technology of absorption heat pumps in various modifications. Technical design draft is created for chosen modification (single stage unit water-LiBr) and based on given parameters calculated in computing software EES (engineering equation solver) and process is explained step-by-step. Following part of thesis contains reference design draft of heat plant and this design is used to demonstrate several different options of applying absorption heat pump including version capable of providing also cooling. Those options are compared with each other from technological and economical stand point.
163

Analýza alternativ odstraňování PCDD/F při spalování odpadů / Evaluation of the alternatives of PCDD/F removing in the incineration plants

Frýba, Lukáš January 2011 (has links)
The thesis is focused on analyzing the current status of the technology used for cleaning flue gas from persistent organic pollutants, especially PCDD/F. For the three most commonly used methods of solution operational and energy efficiency comparison was made, where achievable energy export and the impact of the change in working conditions on the efficiency indicators of energy production and use of the energy was evaluated. In conditions we considered an alternative machine-technological solutions used for the final disposal of persistent organic pollutants resulting from the waste combustion in terms of additional operating costs and energy efficiency.
164

Energetické využití komunálního odpadu / Recovery of Energy from Municipal Wastes

Procházka, Jaroslav January 2011 (has links)
Master’s thesis deal with the design of waste to energy plant of municipal waste. The design of technology is to build the component parts of plant and basic calculation of individual apparatus. Overall technology concists of pretreatment of municipal waste, which is then stored in the bunker. Pretreatment municipal waste is fed into the counterflow rotary kiln. Flue Gates from the kilns are routed through multicyklony in the heat recovery steam generators (HRSG). The multicyklon separates the pollutants. The HRSG generates steam required properties from the feedwater from the heat kontent of gas. Superheated steam is driven to the condensing turbine with extract steam for distrikt rating and for power generation. The flue gas from the HRSG are passed through purification section, in which are separand pollutants the dry method purification. The left heat content of flue gas is used in heat exchanger with twist tube for preheating feed water for the HRSG. The flue gas are fed to the stack.
165

Udržitelnost systémů odpadového hospodářství / Waste management system sustainability

Bravený, Adam January 2014 (has links)
The thesis proposes a new approach to assess sustainability of waste management systems. In the first part current mixed municipal waste (MSW) management system of the Czech republic is reviewed and promising MSW treatment techniques are introduced. In the second part a summary of literature on Life Cycle Assessment (LCA) approach to assess sustainability of MSW systems is provided. A new sustainability assessment model is proposed by implementing LCA to a current tool called NERUDA used to optimize waste management costing. It is demonstrated how to connect these two concepts in order to aquire a powerful tool for sustainability assessment.
166

Středotonážní spalovna odpadů - systém čištění spalin / Incineration plant of middle treatment capacity – flue gas cleaning system

Krejčí, Tomáš January 2015 (has links)
Analysis of the regional energy supply, shows that suitable alternative may be a combination of primary energy sources with the municipal solid waste to energy plant. Starting from the fact that the regional thermal energy needs are characterized by smaller power demand, but relatively significant seasonal fluctuations in heat supply. These factors limit the processing performance of the considered waste to energy plant that could be included in the system of regional energy supply. The aim of the thesis was to propose adequate treatment capacity for regional waste to energy plant and explore alternative solutions in off-gas cleaning for exhaust gases generated during incineration of MSW. The balance sheets of two alternative solutions off gas cleaning are part of the thesis, both in terms of material and energy consumption. Presented evaluation of economic demands alternative arrangement of off gas cleaning includes operating costs and the impact on earnings from energy production.
167

Conflicts and order : controversies over municipal solid waste incineration in China

Zhang, Xixi 01 1900 (has links)
Au cours des dernières décennies, nous avons été témoins de la croissance des controverses relatives à l’incinération des déchets solides municipaux dans de nombreuses villes du monde. Cela est particulièrement vrai pour les grandes et moyennes villes en Chine. Diverses catégories d’acteurs, y compris l’État, les autorités locales, les acteurs du marché économique et de la société civile, tentent d’exercer leur influence sur la construction, l’extension et/ou l’opération des incinérateurs. Même si les controverses relatives à l’incinération des déchets solides municipaux abordées par le passé dans plusieurs disciplines, nous ne sommes pas en présence d’une véritable compréhension collective suffisante de la stabilité et du changement à l’échelle méso. La thèse traite de la question suivante: dans les débats et les affrontements autour de l’incinération, comment et jusqu’à quel point les interactions et les compétitions entre contestataires et adversaires contribuent-elles à définir un champ d’action stratégique où la structure industrielle et les politiques de gestion des déchets dominées par l’incinération sont remises en question ou reconduites ? Pour répondre à cette question, cette étude considère l’incinération des déchets solides municipaux en Chine sous l’angle d’un champ d’action stratégique. Elle essaie de clarifier ce qui se passe dans ce champ sous trois aspects: les acteurs, les actions stratégiques et les retombées politiques. Faisant appel à une démarche de recherche qualitative, un grand volume de données primaires et secondaires a été amassé, y compris 42 entretiens semi-structurés, 557 posts en ligne, des rapports de recherche, des documents d’archives, des rapports d’évaluation de l’impact sur l’environnement, des nouvelles en ligne, des données statistiques et des documents de politique. À l’aide de ces données, cette étude approfondi la compréhension des relations entre, d’un côté les acteurs s’opposant aux activités découlant de l’incinération – les contestataires – et, de l’autre, les adversaires dans le champ d’action stratégique, mettant en lumière leurs arguments respectifs. En outre, le processus par lequel les militants utilisent les réseaux sociaux pour la mobilisation du consensus a reçu une attention supplémentaire. De plus, cette étude a analysé l’évolution des interactions entre les militants et les décideurs politiques et a contextualisé la transformation du champ au cours des dernières décennies. Les résultats ont montré que les controverses autour de l’incinération des déchets solides municipaux sont allées au-delà des préoccupations pour les intérêts personnels et le bien-être environnemental. Cela permet d’introduire des explications plus nuancées comparativement aux discours conventionnels concernant les protestations contre l’incinération, fournissant une compréhension systématique de l’activisme local. Cette analyse exploratoire a permis également de mieux comprendre la signification politique et sociale des controverses publiques à travers des pratiques locales de gestion des déchets. Dans un sens plus large, la thèse permet de revoir les notions usuelles à l’égard des relations entre conflits et ordre. / The past few decades have witnessed the growth of controversies regarding municipal solid waste (MSW) incineration in many cities around the world. This is especially true when it comes to large and medium-sized cities in China. Various categories of actors—including the state, local authorities, market actors, and the civil society—seek to exert their influence on the construction, expansion, and/or operation of incinerators. Even though the controversies over MSW incineration have been discussed across a range of disciplines in previous literature, we are not in the presence of a sufficient collective understanding of stability and change of the meso-level social order. This dissertation addresses the following question: How and to what extent do interactions and competition between pro-incineration and anti-incineration groups contributes to defining a strategic action field (SAF) where the incineration-dominated industrial structure and waste disposal policies are challenged or maintained? To answer the question, this study considers MSW incineration in China an SAF and attempts to clarify what is happening in this SAF from three aspects: actors, strategic action, and policy impacts. Based on a qualitative research design, a great volume of primary and secondary data were collected, including 42 semi-structured interviews, 557 online posts, research reports, archival materials, environmental impact assessment reports, online news, statistical data, and policy documents. With the help of collected data, this study deepened the understanding of the relationship between proponents and opponents in the field of incineration and shed light on their respective arguments. In addition, the process through which activists used social media for consensus mobilization was given additional attention. Moreover, by analyzing the dynamics of the interplay between activists and policy makers, this study revealed and contextualized the evolution of the SAF over the past few decades. The findings showed that controversies around MSW incineration had gone beyond the concerns for personal interests and environmental well-being. This allows to introduce more refined explanations compared to conventional discourses regarding anti-incineration protests and provide a more nuanced understanding of local activism. This exploratory analysis also helped to better understand the political and social significance of public controversies through local practices of MSW management. In a broad sense, this dissertation makes it possible to review the usual conceptions with regard to the relations between conflict and order.
168

Absorpční čištění spalin vznikajících spalováním odpadů / Absorption Cleaning of Flue Gases Arising from the Incineration of Wastes

Jecha, David January 2010 (has links)
This doctoral thesis deals with potentials of methods for cleaning of flue gas from pollutants such as acidic components. Wet method of flue gas cleaning is analysed in detail with special focus on elimination of sulphur dioxide (SO2). Introduction presents advantages and disadvantages of thermal processing of waste and production of undesired pollutants. Following parts comprise facts about main pollutants produced from incineration. Legislation providing for emission of gaseous pollutants from incinerators is also given. Chapter concerning methods of pollutants elimination is mostly focused on absorption (wet and/or semidry scrubber) and adsorption methods. Several up-to-date technological procedures are mentioned; they have a multifunctional effect such as elimination of acidic components, heavy metals, polychlorinated dibenzo-p-dioxines and dibenzo-furanes from flue gas using single injection of suspense. Elimination of mercury (Hg) is among the technologies for heavy metal elimination which is described in detail. Main part of the thesis is related to experiments at two-stage flue gas cleaning equipment. Function of this experimental unit is described along with methods for measurement of individual quantities and detailed description of all the equipment and its components. Experimental measurements carried out at this equipment are explicated and assessed. Along with experimental work, the author has created a simulation model of wet flue gas cleaning in ChemCad programme. Particular operational parameters were tested on this model. This thesis contains results of the measurement which provide background for verification of the mathematical model. Further, the balance of heavy metals conducted on the basis of measurements in waste incinerator is displayed. Main contribution of the thesis may be summed up as follows: ­ Author has designed and constructed experimental equipment for two stage flue gas cleaning. ­ He also formed calculation for pressure drop of O-element prototype equipment and for packing column with FLEXIPAC structured packing. ­ He created data file with measurements at the experimental unit. ­ He determined temperature at outlet of a random device where liquid is injected into stream of hot flue gas. ­ He designed a simulation model which is identical with experimental equipment and which usage enabled comparison of measured and calculated data; it also serves as a basis for industrial applications. ­ Last part deals with creation off heavy metals balance in a case industrial waste incinerator.
169

Analyzing Key Flows and Processes of Waste Management for Environmental Improvement in Chennai, India : A Minor Field Study with a Life Cycle and Socio-Technical Systems Perspective / Analys av viktiga flöden och processer inom avfallshantering för miljöförbättring i Chennai, Indien : En fältstudie med ett livscykel- och sociotekniskt systemperspektiv

Selander, Märta January 2023 (has links)
Waste management (WM) is a prominent issue in the world’s most populated country, India. Lack of WM can have a negative impact on the environment through leachate contamination of water bodies and emissions of greenhouse gases. The purpose of this study was to thoroughly map WM processes in South East India and identify areas with potential for environmental improvement. This was conducted in three steps: by mapping the flows in a WM system in Chennai (India), by qualitatively assessing these flows through a literature review of articles published in the field, and by interviewing representatives from the company that are responsible for the collection and transportation of waste to identify what challenges the process faces and how they can be addressed. The main finding from the study was that the lack of site-specific data made it difficult to quantitatively assess the global warming potential of the process; however, it is possible to make a qualitative analysis. From study visits to the different treatment facilities, it was clear that energy recovery is a technical solution that could reduce the GWP of the process. Additionally, it became clear that the process should be seen as a socio-technical system, as the studied process is currently focusing on developing and improving the social elements of the process. These social elements include getting the residents to segregate their waste through education in schools and door-to-door collection. The results also showed how an improved cultural perception on WM could potentially influence several of the identified challenges in the process and their respective solutions. Finally, the study highlighted the importance of conducting more in-depth research to enable the implementation of an LCA that can contribute with valuable results. / Avfallshantering är en viktig fråga i världens mest befolkade land, Indien. Bristande avfallshantering kan ha en negativ inverkan på miljön genom att lakvatten förorenar vattendrag och utsläpp av växthusgaser. Syftet med den här studien var att noggrant kartlägga en process för avfallshantering i sydöstra Indien och identifiera områden med potential för miljöförbättringar. Detta genomfördes i tre steg: genom att kartlägga flödena i ett avfallshanteringssystem i Chennai (Indien), genom att kvalitativt bedöma dessa flöden genom en litteraturgenomgång av artiklar som publicerats på området och genom att intervjua representanter från det företag som ansvarar för insamling och transport av avfall för att identifiera vilka utmaningar som processen står inför och hur de kan åtgärdas. Det viktigaste resultatet av studien var att bristen på platsspecifika data gjorde det svårt att kvantitativt bedöma processens globala uppvärmningspotential (GWP), men att det var möjligt att göra en kvalitativ analys. Vid studiebesöken vid de olika behandlingsanläggningarna blev det tydligt att energiåtervinning är en teknisk lösning som skulle kunna minska processens GWP. Dessutom blev det tydligt att processen bör ses som ett sociotekniskt system, eftersom den studerade processen för närvarande fokuserar på att utveckla och förbättra processens sociala element. Dessa sociala element omfattar att få invånarna att sortera sitt avfall genom utbildning i skolor och insamling av avfall från dörr till dörr. Resultaten visade också hur en förbättrad kulturell uppfattning om avfallshantering potentiellt skulle kunna påverka flera av de identifierade utmaningarna i processen och deras respektive lösningar. Slutligen betonade studien vikten av att genomföra mer djupgående forskning för att möjliggöra genomförandet av en LCA som kan bidra med värdefulla resultat.
170

Modelagem matemática para a localização ótima de usinas de incineração com recuperação energética de resíduos sólidos domiciliaries: uma aplicação para Região Metropolitana da Baixada Santista e Litoral Norte / Mathematical modeling for the optimal location for incineration plants with energy recovery from municipal solid waste: an application to the Santos Metropolitan Region and North Coast

Heiderich, Nadja Nara Lima 27 January 2012 (has links)
A presente pesquisa teve por objetivo propor uma estrutura de modelagem matemática para a localização ótima de unidades de tratamento térmico de resíduos com recuperação energética. Para tal, o ferramental utilizado foi o método de programação inteira mista, sendo a modelagem desenvolvida aplicada para a Região Metropolitana da Baixada Santista e Litoral Norte. Foi considerada como premissa básica que o processo de incineração seria operado pelo poder público; todos os municípios geradores de Resíduos Sólidos Domiciliares foram considerados como potenciais localidades para a instalação da unidade de tratamento térmico de resíduos; todos os aterros sanitários que atendiam os Municípios estudados foram considerados para a recepção das escórias e cinzas provenientes do processo de incineração. Foram especificados quatro cenários para tal análise, que abordaram competitividade em relação ao uso de aterros sanitários e a presença de eficiência na coleta seletiva dos Municípios. Os resultados apontaram para que a unidade de tratamento térmico de resíduos se localize no entorno dos Municípios de Santos, Praia Grande e São Vicente. Mesmo com a opção do uso de aterros sanitários, a implantação da unidade de tratamento térmico de resíduos se apresentou como uma alternativa mais favorável, tendo sido levados em conta, na modelagem proposta, aspectos tanto ambientais como econômicos. / This study aimed to propose a mathematical modeling framework for optimal location of units of the thermal treatment of waste with energy recovery. To this end, the tool used was the method of mixed integer programming, and the developed modeling applied to the Santos Metropolitan Region and North Coast. It was considered as the basic premise that the incineration process would be operated by the Government; all municipalities solid waste generators were considered as potential locations for the installation of the unit thermal treatment of waste, all landfills that serve municipalities studied were considered for receipt of slag and ash from the incineration process. Four scenarios were specified for this analysis that addressed competitiveness in relation to the use of landfills and the presence of selective collection efficiency in the municipalities. Results showed that the unit of thermal treatment of waste should be located in the vicinity of the cities of Santos, São Vicente and Praia Grande. Even with the option of using landfill, the deployment of the unit of thermal treatment of waste is presented as an alternative more favorable, having been taken into account in the proposed model, both environmental and economic aspects.

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