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Pyrolysis of Waste Electrical and Electronic Equipment (WEEE) Plastics for Energy and Material RecoveryAsvestas, Ioannis January 2018 (has links)
The society is striving to tackle the over-extraction of Earth’s resources due to the ongoing population rise. The increased needs of energy and material resources leads to a growing volume of materials waste, which include a variety of dangerous pollutants among them. Waste of electrical and electronic equipment poses a universal problem due to its vast quantities, responsible for environmental pollution and numerous diseases to humans and animals. The high demand in electrical and electronic equipment along with its short-life time due to its obsolescence, leads to the expansion of WEEE waste stream. Energy and material recovery from WEEE can minimize significantly the over extraction of precious metals and minerals along with fuels towards a more sustainable future. Currently, there are several ways to treat WEEE and recover material fractions along with energy, such as incineration and landfilling. Thermochemical treatment of WEEE offers the possibility to convert waste into energy and material simultaneously, in an environmentally friendlier way, resulting in a more sustainable waste management. In this research, pyrolysis is examined as a method for energy and material recovery from WEEE. Brominated plastics along with Polyethylene plastic mixtures have been acquired from Stena and Boliden AB separation processes respectively. Both materials are subjected to pyrolysis in a fixed bed and an auger reactor. The pyrolysis products show their strong relation to the pyrolysis temperature, the type of the reactor and the initial composition of the feedstock material. The carried-out experiments depict the upward trend of the gaseous products in favor of the oils as the pyrolysis temperature increase. The amount of solid residue remained almost at the same levels throughout the temperature range, meaning that no higher temperatures are needed in order to achieve higher decomposition rates of the tested material. Unreacted carbon and inorganic compounds end up in the solid residue that could be used as fuel in a combustion process. The metal fraction can be separated and recycled, as it possesses commercial value. Main oil compounds listed were, styrene, toluene, ethylbenzene, alpha methylstyrene benzene, phenol. Compounds such as benzene, indene and p-xylene were produced as the organic compounds were further decomposed during the experiments at the highest temperatures. Chlorine and bromine content must be separated in order to be a formidable fuel. The amount of combustible gases was increasing and their energy potential with the temperature rise. The gaseous fraction consists mainly of: H2, CO, CH4, CO2, C2H2, C2H4, C2H6, C3H6, C3H8. Both the gaseous and oil compounds can be used as fuels in a combustion process. The amount of halogens was measured at low levels within the product range, though their separation is important. Pyrolysis of WEEE is a promising method for energy and material recovery that can boost the sustainability of our society. / Samhället strävar efter att ta itu med överutvinningen av jordens resurser på grund av den pågåendebefolkningsökningen. De ökade behoven hos energi och materiella resurser leder till en ökandemängd materialavfall, vilket inkluderar en mängd farliga föroreningar bland dem. Avfall av elektriskoch elektronisk utrustning utgör ett universellt problem på grund av sin stora mängd, ansvarig förmiljöföroreningar och många sjukdomar hos människor och djur. Den stora efterfrågan på elektriskoch elektronisk utrustning tillsammans med den korta livslängden på grund av dess föryngring ledertill utvidgningen av WEEE-avfallsströmmen. Energi och materialåtervinning från WEEE kanbetydligt minska över-extraktion av ädelmetaller och mineraler tillsammans med bränslen mot en merhållbar framtid. För närvarande finns det flera sätt att behandla WEEE och återvinna materialfraktioner tillsammansmed energi, såsom förbränning och deponering. Termokemisk behandling av WEEE erbjudermöjlighet att omvandla avfall till energi och material samtidigt, på ett miljövänligare sätt, vilketresulterar i en mer hållbar avfallshantering.I denna forskning undersöks pyrolys som en metod för energi och materialåtervinning från WEEE.Bromerad plast tillsammans med polyetylenplastblandningar har förvärvats från Stena och BolidenAB separationsprocesser. Båda materialen utsätts för pyrolys i en fast bädd och en skruvreaktor.Pyrolysprodukterna visar deras starka förhållande till pyrolys-temperaturen, reaktortypen och denursprungliga sammansättningen av råmaterialet. De utförda experimenten visar den uppåtgåendetrenden hos de gasformiga produkterna till förmån för oljorna som pyrolystemperaturökningen.Mängden fast substans förblev nästan vid samma nivåer genom temperaturintervallet, vilket innebäratt inga högre temperaturer behövs för att uppnå högre sönderdelningshastigheter för det testadematerialet. Oreagerat kol och oorganiska föreningar hamnar i den fasta återstoden som kan användassom bränsle vid förbränningsprocessen. Metallfraktionen kan separeras och återvinnas, eftersom denhar kommersiellt värde. De angivna huvudolja-föreningarna var styren, toluen, etylbensen, alfa-metylstyrenbensen, fenol.Föreningar såsom bensen, inden och p-xylen framställdes när de organiska föreningarnasönderdelades vidare under försöken vid de högsta temperaturerna. Klor och brominnehåll måstesepareras för att vara ett formidabelt bränsle.Mängden brännbara gaser ökade och deras energipotential med temperaturökningen. Den gasformigafraktionen består huvudsakligen av: H2, CO, CH4, CO2, C2H2, C2H4, C2H6, C3H6, C3H8. Bådegasformiga och oljeföreningar kan användas som bränslen i en förbränningsprocess. Mängdenhalogener mättes vid låga halter inom produktsortimentet, fastän deras separation är viktig.Pyrolys av WEEE är en lovande metod för energi och materialåtervinning som kan öka vårt samhälleshållbarhet.
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Product Design For Repairability: Identifying Failure Modes With Topic Modeling And Designing For Electronic Waste ReuseFranz, Claire J 01 June 2024 (has links) (PDF)
Design for repairability is imperative to making products that last long enough to justify the resources they consume and the pollution they generate. While design for repairability has been gaining steady momentum, especially with recent advances in Right to Repair legislation, there is still work to be done. There are gaps in both the tools available for repair-conscious designers and the products coming onto store shelves. This thesis work aims to help set sails in the right direction on both fronts.
This research explores the use of topic modeling (a natural language processing technique) to extract repairability design insights from online customer feedback. This could help repair-conscious designers identify areas for redesign to improve product repairability and/or prioritize components to provide as available replacement parts. Additionally, designers could apply this methodology early in their design process by examining the failure modes of similar existing products.
Non-Negative Matrix Factorization (NMF) and BERTopic approaches are used to analyze 5,000 Amazon reviews for standalone computer keyboards to assess device failure modes. The proposed method identifies several failure modes for keyboards, including keys sticking, legs breaking, keyboards disconnecting, keyboard bases wobbling, and errors while typing. An accelerated product design process for a keyboard is presented to showcase an application of the topic modeling results, as well as to demonstrate the potential for product design that uses a “piggybacking” design strategy to reuse electronic components. This work indicates that topic modeling is a promising approach for obtaining repairability-related design leads and demonstrates the efficacy of product design to reduce e-waste.
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Prvky vzácných zemin v elektroodpadech / Rare earth elements in electronic wastePospíšilová, Eliška January 2014 (has links)
Rare earth elements consist of 15 lanthanides, Y and Sc. They are currently very important materials in many industrial branches (metalurgy, pollishing). One of these options is the usage as the compound of phosphors in electronic devices (television and computer displays. Because of their manufacturing cost, options of recovery from waste electrical and electronic equipment (WEEE) are investigated. This thesis deals with compoud elements of phosphors from displays of type CRT (cathode ray tube) and plasma TV. The 37 samples of phosphors from different displays were taken and processed for study of the compoud elements. Phosphors were separated to 4 subgroups in accordance with the corresponding type of displays: black-and-white CRT television displays (CRT_CB), color CRT television displays (TV_B), color PC displays (PC_B) and monochromatic PC displays (PC_M). The study was carry out by multiple features analysis that combined the inductively coupled plasma mass spectrometry (ICP-MS), the inductively coupled plasma optical emission spectrometry (ICP-OES), the resistance furnace with infrared detector (RF-IF) and the atomic absorption spectrometry (AAS). Based on the results of this analysis, main elements and potentionally hazardous elements of phosphors subgroup were defined. Concentration of rare...
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Design of hybrid nano-composite adsorbent for recovery of Pd And Au from electronic wastewater / Conception d'un absorbant hybride nano-composite pour la récupération du palladium et de l'or dans les eaux usées électroniquesTrieu, An 18 December 2018 (has links)
Les sources secondaires de métaux précieux, tels que les déchets électroniques, ont récemment attiré l’attention générale suite à la sensibilisation sur l’épuissement des ressources naturelles et sur l’industrie du recyclage sur l’emploi et la croissance économique. Developper des technologies de recyclage qui permettent l’extraction de palladium (Pd) et d’or (Au) en très faibles concentrations (10-100 ppm) dans les effluents électroniques s’avère aujourd’hui économiqueemnt viable.Dans ce contexte, notre étude aborde l’utilisation de nanoparticules de ZrO2 modifiées avec des ligands complexants en surface pour capturer efficacement et sélectivement des ions Pd(II) et Au(III) dan les effluents électroniques. Les avantages de l’utilisation de acide thioctique commercial (TOA) par rapport aux acides dialkyldiglycoamide ou (N, N)-dialkylcarbamoylméthylphosphoniques en termes de capacité d’adsorption et de sélectivité ont été démontrés. Des expériences d’adsorption en mode batch combinées à la méthode ICP-OES ont été réalisées et nos résultats ont montré des capacités d’adsorption envers le Pd et l’Au de 6.3 mg/g et de 43 mg/g, respectivement. Les processus d’adsorption suivaient le modèle de Langmuir et les cinétiques chimiques d’adsorption étaient mieux adaptés à l’équation du pseudo-second ordre. Les conditions d’optimisation pour la mise en place du stripping sélectif à l’aide de solutions acidifiées de thiourée ont également été étudiées. En particulier, afin d’améliorer la réutilisation de ce matériau hybride, des processus de modification des surface en deux étapes ont été développés par fonctionnalisation de la surface de nano-ZrO2 avec de l’acide alendronique et par une réaction de couplage peptidique avec du TOA.De plus, les procédés de greffage de nano-ZrO2 sur un textile en polypropylène modifié avec les groupements carboxylique ont été étudiés via des méthodes traditionnelles de revêtement par immersion (dip-coating) et de revêtement couche par couche (LbL). Cette dernière s’est avérée être une méthode prometteuse en termes de flexibilité, de facilité de manipulation et de respect de l’environnment. Les nanocomposites obtenus ont démontré d’excellentes propriétés d’adsorption de Pd et d’Au / Secondary sources of precious metals, such as e-waste, have been recently gaining more attention thanks to raising awareness of natural resources depletion and sound impact of recycling industry on employment and economic growth. Recycling technologies have now to be developed, enabling extraction of very small concentration (10-100 ppm) of precious metals, such as palladium (Pd) and gold (Au), from effluents of recycling factories economically viable.In this context, our study addresses the use of thioctic surface-modified zirconia nanoparticles to capture efficiently and selectively Pd(II) and Au(III) ions from industrial electronic wastewater. The advantages of using the commercial thioctic acid (TOA) over dialkyldiglycoamide or (N,N)-dialkylcarbamoylmethylphosphonic acids ones in terms of adsorption capacity and selectivity were demonstrated. Batch-mode adsorption experiments combined with ICP-OES method were conducted and our findings have displayed adsorption capacities toward Pd and Au of 6.3 mg/g and 43.3 mg/g, respectively. The adsorption processes were found to follow the Langmuir model and adsorption rates were best-fitted to pseudo-second order equation. The optimization conditions for selective stripping set-up using acidified solutions of thiourea were also investigated. Particularly, in order to improve the reusability of this hybrid nanomaterial, two-step surface modification processes were developed through alendronic acid-surface functionalization of nano-ZrO2 and amide coupling reaction with TOA.Furthermore, the grafting processes of nano-ZrO2 onto carboxylic-modified polypropylene textile were studied via traditional dip-coating and layer-by-layer coating methods. It has been realized that layer-by-layer coating method is a promising method in terms of its flexibility, ease of handling, and environmental friendliness
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Die Kreislaufwirtschaft bei Elektro- und Elektronikgeräten /Vogl, Norbert. January 2007 (has links)
Zugl.: Regensburg, Universiẗat, Diss., 2007.
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Constructing Politics : Discrepancy and Discourses in the E-waste Domain / Att konstruera politik : diskrepans och diskurser i elektronikavfallsdebattenEnvall, Fredrik, Forsman Hedman, Martin January 2012 (has links)
The societal benefits of new technology and electronic products can hardly be underestimated. However, new technological achievements bring problems as well since obsolete products, due to ever-growing amounts and complex composition, are difficult to handle in a sound manner. Currently electronic waste constitutes the single fastest growing waste stream in society. It is also common that e-waste is exported to low-income countries where it generally is recycled under rudimentary conditions, leading to large-scale environmental and health effects. The political handling of the issue has enjoyed moderate success internationally as well as nationally. The shaping of environmental politics is however, according to many researchers, a complex process involving many actors, something that generally is not reflected inofficial politics. The purpose of this thesis is to map out the different discourses inherent in the public debates on e-waste in Sweden and the USA respectively, and compare how they might influence the political management of the e-waste issue. A number of newspaper articles, reports and press releases from NGOs and trade organizations have been analyzed with a discourse analysis method, influenced by John Dryzek and Michel Foucault. The term “order of discourse” has been borrowed by Norman Fairclough as an analytical tool. In the U.S. material a conflictual, unclear order of discourse appeared where most of the actors were portrayed as equal political players. However there was an apparent red thread as the question was framed as an economic issue by the majority of actors. In the Swedish material a very clear order of discourse was identified, where mainly two discourses were dominant. Drawing on the analysis it could be concluded that there were several probable explanations for the contemporary political handling. The perspective of the key actors El-Kretsen and the U.S. EPA was concluded to impair the political handling, while the framing of the issue as a question for experts in the Swedish material was considered another explanation. / Samhällsnyttan med ny teknik och elektroniska produkter kan knappast underskattas. Nya tekniska landvinningar medför dock problematik då elektronikavfall är svåromhändertaget på grund av dess komplexa sammansättning. Numera är dessutom elektronikavfall det enskilt snabbast växande avfallsflödet i samhället. Ytterligare problematik uppstår då det är vanligt att avfallet exporteras till låginkomstländer där det ofta återvinns med primitiva metoder, vilket leder till att avfallet utgör stora miljö- och hälsorisker. Sammantaget innebär detta att elektronikavfall utgör en av de största miljöpolitiska utmaningarna, men den politiska hanteringen av frågan har hittills rönt blandad framgång internationellt såväl som nationellt. Skapandet av miljöpolitik är dock enligt många teoretiker en komplex process som involverar många aktörer, något som generellt inte avspeglas i officiell politik. Syftet med denna uppsats är att försöka urskilja vilka diskurser som finns i den offentliga debatten om elektronikavfall i USA och Sverige, och jämföra hur de kan tänkas påverka den politiska hanteringen av elektronikavfallsfrågan. Ett antal tidningsartiklar, rapporter och pressreleaser från NGO:s och branschsammanslutningar har analyserats med en diskursanalytisk metod, influerad av John Dryzek och Michel Foucault. Begreppet ”diskursordning” har lånats av Norman Fairclough för att som analytiskt verktyg koppla diskursanalysen till den politiska hanteringen i respektive land. I det amerikanska materialet framträdde en konfliktfylld, otydlig diskursordning där flertalet aktörer framställdes som likvärdiga politiska spelare. Det fanns en tydlig röd tråd i det faktum att samtliga aktörer diskuterade frågan utifrån ett ekonomiskt perspektiv. I det svenska materialet fanns istället en tydlig diskursordning, där framförallt två diskurser var förhärskande. Utifrån analysen kunde konstateras att det fanns ett antal troliga skäl till den nuvarande politiska hanteringen. Nyckelaktörerna El-Kretsen och det amerikanska Naturvårdsverkets perspektiv lyftes som två troliga anledningar, medan inramningen som en expertfråga i det svenska materialet framhålls som ytterligare en orsak.
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Trace metal contamination of the riverine environment in Guiyu, China: the impacts of primitive e-wastedisposalWong, Sze-chung, Coby., 黃詩頌. January 2009 (has links)
published_or_final_version / Earth Sciences / Doctoral / Doctor of Philosophy
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Modo de cuidar do lixo eletroeletrônico: analisando mudanças na ação dos estudantes em oficinas ambientais na escola de ensino médio Lauro Rebouças de Oliveira em Limoeiro do Norte-CE / Method of taking care of eletroeletronic waste: analyzing changes in students' actions in environmental workshops at Lauro Rebouças de Oliveira high school in Limoeiro do Norte-CECastro, Maria do Socorro Santos de Assis 21 February 2017 (has links)
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Previous issue date: 2017-02-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This research examines together with students from the state public school Lauro Rebouças de Oliveira de Limoeiro do Norte-Ce, the changes in the coordinations of actions in an environmental education experience focused on the disposal and treatment of electronic and electronic garbage in school. Electrical and electronic waste grows disorderly every day as a consequence of the changes in our society, when the relations human being - technical object happen amid the integration of increasingly powerful digital technologies in the various daily actions. It is a particularly dangerous, toxic waste and therefore harmful to the environment and human health, so it is crucial to focus the research intervention on environmental education in the e-waste issue, because it involves the relationship man-nature that is Essential for the well-being of all humanity. (SOUSA, 2009) This differentiated look that we are launching for this reality makes us perceive the world as an integrated whole, where the subjects recognize themselves as part of the environment. The theoretical support network of research is supported by the studies of Tundisi (1997) and Carvalho (1991), constructions on the problem of garbage and environmental education; And Simondon (1989), philosopher and physicist, a classic that helps us to situate the relation between the processes of human, technical and physical individuation in the configuration of the set we call society. The main objective of the research is to analyze the coordinations of the actions of students of a public high school about an experience of gathering the electroelectronic and to deepen the study on the destination of this garbage in the municipality of Limoeiro do Norte.The methodology chosen for development is the intervention research of a qualitative nature and we will use the Jean Paul Thibaud (2004) commented path method to distinguish and evaluate the actions and transformations carried out by the collective of students engaged in the research during the course. This methodology Allows to analyze the environment through the observation and recurrences and / or differences identified in excerpts from the workshops and the transcripts of comments of the course, referring to the direct experience of the students in the moments in which they dedicate themselves to the project in progress in the school of collection and forwarding of the trash Electro-electronic. As a result of the research, we were able to distinguish changes in the ways of perceiving the problem of electro-electronic waste in the students' experience, knowledge and knowledge that can contribute with advances in the experience of Environmental Education focused on contemporary problems, produce changes in actions directed to the treatment of electronic and electronic waste The students' experience in school and the strengthening of public policies aimed at the treatment of electronic waste, based on the experience of a group of students from a secondary school in Limoeiro do Norte / Essa pesquisa examina juntamente com estudantes da escola pública estadual Lauro Rebouças de Oliveira de Limoeiro do Norte-Ce, as mudanças nas coordenações de ações em uma experiência de educação ambiental focada no descarte e tratamento do lixo eletroeletrônico na escola. O lixo eletroeletrônico cresce desordenadamente a cada dia como consequência das mudanças em nossa sociedade, quando as relações ser humano – objeto técnico acontecem em meio à integração de tecnologias digitais cada vez mais potentes nas diversas ações cotidianas. Trata-se de um lixo especialmente perigoso, tóxico e, portanto, nocivo ao meio ambiente e à saúde humana, por isso é crucial focarmos a pesquisa intervenção em educação ambiental na questão do e-lixo, porque envolve a relação homem-natureza que é essencial para o bem-estar de toda humanidade. (SOUSA, 2009). Esse olhar diferenciado que ora lançamos para essa realidade nos faz perceber o mundo como um todo integrado, onde os sujeitos reconhecem-se como parte do meio ambiente. A rede teórica de sustentação da pesquisa encontra apoio nos estudos de Tundisi (1997) e Carvalho (1991), construções sobre a problemática do lixo e da educação ambiental; e Simondon (1989), filósofo e físico, um clássico que nos ajuda a situar como acontece a relação entre os processos de individuação humana, técnica e física na configuração do conjunto que designamos como sociedade. O objetivo central da pesquisa é analisar as coordenações de ações de estudantes de uma escola pública de ensino médio sobre uma experiência de recolhimento do eletroeletrônico e aprofundamento do estudo sobre a destinação desse lixo no município de Limoeiro do Norte.
A metodologia escolhida para o desenvolvimento é a pesquisa-intervenção de natureza qualitativa e empregaremos o método do percurso comentado Jean Paul Thibaud (2004) para distinguir e avaliar as ações e transformações realizadas pelo coletivo dos estudantes engajados na pesquisa no decorrer do percurso. Esta metodologia permite analisar o ambiente através da observação e recorrências e/ou diferenças identificadas em excertos das oficinas e as transcrições de comentários do percurso, referidos à experiência direta dos estudantes nos momentos em que se dedicam ao projeto em andamento na escola de coleta e encaminhamento do lixo eletroeletrônico. Como resultado da pesquisa, pudemos distinguir mudanças nos modos de perceber a problemática do lixo eletroeletrônico na experiência dos estudantes, saberes e conhecimentos que podem contribuir com avanços na experiência da Educação Ambiental voltada a problemas contemporâneos, produzir mudanças nas ações dirigidas ao tratamento do lixo eletroeletrônico na experiência dos estudantes na escola e, ainda, no fortalecimento de políticas públicas direcionadas ao tratamento de resíduos eletrônicos, a partir da experiência de um grupo de estudantes de uma escola de ensino médio de Limoeiro do Norte / 2017-07-27
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Application des liquides ioniques à la valorisation des métaux précieux par une voie de chimie verte / Electrochemical recovery of pure or alloyed precious metals in ionic liquid electrolytesBilly, Emmanuel 10 February 2012 (has links)
À ce jour, la récupération de métaux précieux contenus dans les déchets d’équipements électriques et électroniques (DEEE) se fait par des procédés présentant un niveau de dangerosité certain du fait de l’utilisation de cyanure ou d’eau régale qui impactent l’environnement avec une toxicité notoire pour l’homme dans le cas des cyanures. C’est dans la perspective de répondre à ces enjeux environnementaux que le projet PEPITE a été construit en associant un industriel (RECUPYL®) le LEPMI avec le soutien de L’ADEME. L’objet du projet vise à récupérer les métaux précieux contenus dans les DEEE par un procédé utilisant des liquides ioniques (LIs). Les travaux ont permis de compiler une base de connaissance très utile sur les propriétés physicochimiques des liquides ioniques retenus. Nous avons également pu bâtir un schéma de traitement aussi efficace mais sans rejet de gaz toxiques ou d’effluents. Les résultats de nos travaux ont conduit à l’émergence d’une nouvelle voie de recyclage par chimie verte grâce à l’application des liquides ioniques. Enfin, cet avantage environnemental s’accompagne d’une viabilité économique en regard des procédés actuels. / To date, the recovery of precious metals contained in waste electrical and electronic equipment (WEEE) reported a significant level of danger due to the use of cyanide or aqua regia extremely harmful and dangerous to the humans and the environment. This is in view to respond to environmental and economic issues that RECUPYL® society, LEPMI laboratory and the French Environment and Energy Management Agency (ADEME) developed the PEPITE project. It aims to recover the precious metals contained in WEEE by a hydrometallurgical process using ionic liquid electrolytes (ILs). This work led us to establish a knowledge base and to make measurements on the physico-chemical properties of LIs. We were able to develop a process flow sheet without release neither toxic gases nor effluents. The research work undertaken has led to significant results and demonstrated that there is a real solution for the recovery of precious metals in ionic liquid electrolyte.
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Caracteriza??o de placas de circuito impresso oriundas de telefones celulares e recupera??o de cobre / Circuit boards printed characterization coming from mobile phones and copper recoveryJesus, Theo Antonio de 23 January 2015 (has links)
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Previous issue date: 2015-01-23 / Technological advances encourages the constant exchange of electronic equipment by increasing the amount of waste generated. The concern with the disposal of these wastes is related to the amount of available metals and final disposal, which usually occurs in dumps or landfills. These wastes have precious metals and other trace elements that are released into the environment by leaching from the organic acid attack. Most of these residues has printed circuit boards in which are concentrated the most metals, and the characterization of these plates help to choose the most appropriate recycling processes. This study aimed to characterize the printed circuit boards of mobile phones as its danger and composition as well as preliminarily investigate the possibility of copper recovery via an electrolytic process and test a mixture of coagulant / flocculant in the removal of metals, including copper. The plates were ground knives in order to release the metals and then separating the particle size was made in three fractions of different sizes. Each of the fractions was characterized by digestion in aqua regia, diffraction and X-ray fluorescence characterization, as the danger was performed through recommended by the ABNT NBR 10005. In the fractions resulting from the grain size were performed gravity separations. For the recovery of copper was used in electrolytic technique medium prepared with the electrolyte coming from the gravimetric fraction with a higher concentration of metals. The copper recovery efficiency through electrolytic process was evaluated by the decrease of its concentration in the electrolyte at five different times. Also, the use of coagulant mixture / flocculant had their efficiency assessed by check which proportion coagulant / flocculant used resulted in solution with lower concentrations of metals. It is also made of copper recovery compared by both methods. Mechanical processes are used to promote adequate concentration of most metals with approximately 80% in the coarser fraction using the separation grain size. The characterization results showed that the printed circuit boards of mobile phones are rich in copper, mean values reaching 40%, in addition to having small amounts of gold and silver. In the study of danger, lead levels were found in amounts well above the limit established by ABNT NBR 10004, requiring specific treatments at the disposal of this type of waste. Some proportions coagulant / flocculant used produced better results than others, getting, on average, above 90% removal. The recovery of copper showed better performance using the electrolytic process, compared to that obtained at any ratio coagulant / flocculant used once reached 98.05 % after 40 minutes. It was estimated the average revenue generated in the recovery of metals from the main printed circuit boards of mobile phones discarded in 2013 in Brazil, reaching the amount of US $ 6,182,263.06 / O avan?o tecnol?gico incentiva a troca constante dos equipamentos eletroeletr?nicos aumentando a quantidade de res?duos gerados. A preocupa??o com a disposi??o desses res?duos est? relacionada com a quantidade de metais existentes e sua disposi??o final, que geralmente se d? em lix?es ou aterros. Estes res?duos apresentam metais preciosos e outros elementos tra?os que s?o liberados no meio ambiente pela lixivia??o proveniente do ataque de ?cidos org?nicos. A maior parte destes res?duos possui placas de circuito impresso onde est? concentrada a maior parte dos metais, sendo que a caracteriza??o destas placas ajuda na escolha dos processos de reciclagem mais adequados. Este trabalho teve como objetivo caracterizar as placas de circuito impresso de telefones celulares quanto sua periculosidade e composi??o, bem como investigar preliminarmente a possibilidade de recupera??o de cobre via um processo eletrol?tico e testar uma mistura de coagulante/floculante na remo??o de metais, inclusive cobre. As placas foram processadas em moinho de facas, a fim de liberar os metais e, em seguida, foi feita a separa??o granulom?trica em tr?s fra??es de diferentes tamanhos. Cada uma das fra??es foi caracterizada por digest?o em ?gua r?gia, difra??o e fluoresc?ncia de raios X. A caracteriza??o, quanto ? periculosidade, foi realizada por meio do preconizado pela NBR ABNT 10005. Nas fra??es oriundas da granulometria foram realizadas as separa??es gravim?tricas. Para a recupera??o de cobre foi utilizada a t?cnica eletrol?tica por meio de eletr?lito preparado com a fra??o oriunda da gravimetria com maior concentra??o de metais. A efici?ncia da recupera??o de cobre via processo eletrol?tico foi avaliada por meio da diminui??o de sua concentra??o no eletr?lito em cinco tempos diferentes. J? a utiliza??o da mistura coagulante/floculante teve sua efici?ncia avaliada pela verifica??o de qual propor??o coagulante/floculante utilizada resultou em solu??o com menor concentra??o de metais. Fez-se tamb?m a compara??o de recupera??o de cobre por ambos os m?todos. Os processos mec?nicos utilizados foram adequados para promoverem a concentra??o da maioria dos metais alcan?ando cerca de 80 % na fra??o mais grosseira utilizando-se a separa??o granulom?trica. Os resultados da caracteriza??o mostraram que as placas de circuito impresso de celulares s?o ricas em cobre, alcan?ando valores m?dios de 40 %, al?m de apresentarem pequenas quantidades de ouro e prata. No estudo de periculosidade, foram encontrados n?veis de chumbo em quantidades muito acima do limite estabelecido pela NBR ABNT 10004, sendo necess?rios tratamentos espec?ficos no descarte deste tipo de res?duo. Algumas propor??es de coagulante/floculante utilizadas produziram resultados mais satisfat?rios que outras, ficando, na m?dia, acima dos 90 % de remo??o. A recupera??o de cobre apresentou melhor desempenho utilizando processo eletrol?tico, quando comparado ao obtido a qualquer propor??o de coagulante/floculante utilizada, uma vez que alcan?ou 98,05 % ap?s 40 minutos. Foi estimada a receita m?dia gerada, na recupera??o dos principais metais contidos nas placas de circuito impresso dos telefones celulares, descartados em 2013, no Brasil, chegando-se ao valor de US $ 6.182.263,06.
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