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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.
71

Procédé de recyclage de mélanges ABS-PC issus de déchets d’équipements électriques et électroniques (DEEE) / Mechanical recycling of PC-ABS blend from waste electrical and electronic equipement

Ausset, Sandrine 08 February 2013 (has links)
L’objectif de cette thèse est de proposer un procédé de recyclage de mélanges ABS-PC issus des Déchets d’Equipements Electriques et Electroniques (DEEE) réels capable de s’affranchir des contraintes liées au recyclage des polymères.Ces contraintes sont liées, entre autre, à la présence d’impuretés (autres polymères) après l'étape de tri et au procédé de remise en forme. L’influence de la présence d’impureté dans un alliage ABS-PC sur ces propriétés mécaniques (résistance au choc et traction) a donc été étudiée en s’appuyant sur des observations morphologiques. Il s’est avéré que la présence d’impureté non miscible conduit à la dégradation des propriétés mécaniques de l’ABS-PC. L’ajout de compatibilisants a été étudié afin de masquer l’effet de l’impureté. Il a ainsi été montré que l’amélioration de la résilience du mélange (ABS-PC/impureté) est intimement liée à la modification de la morphologie et à la nature de l’adhésion aux interfaces. Il a ensuite été constaté que l’optimisation des paramètres de mise en oeuvre engendre une modification de la morphologie. Cette modification peut entrainer une augmentation de la résistance au choc.Ces deux méthodes ont ensuite été appliquées à un mélange d’ABS-PC ignifugé issu des DEEE contenant une impureté. L’ajout de compatibilisant et de la modification des paramètres de mise en oeuvre améliore la résilience. En revanche, cela a un effet néfaste sur le comportement au feu de l’alliage ABS-PC ignifugé. / The aim of this PhD work was to propose a recycling process method of PC-ABS blend from real Waste Electrical and Electronic Equipment deposit (WEEE) deposits. This recycling process has to be able to overcome the problematic related to polymer recycling.The main constraints about recycling process are the presence of polymeric impurities after sorting step as well as mechanical reprocessing (extrusion and injection molded). Firstly, the effect of impurities on the mechanical properties (tensile and impact strength) and morphology (SEM, TEM) of PC-ABS blends have been studied. The presence of immiscible impurity deteriorates the mechanical properties of PC-ABS. The addition of an appropriate compatibilizer enhances the interface between PC-ABS and the impurity. The compatibilizer improves the impact strength and changes the morphology of this blend. Secondly, the optimization of injection molding parameters generates a change in morphology. This change leads to an increase of the impact strength.Both methods were applied to a flame retardant PC-ABS from WEEE with an impurity. The addition of a compatibilizer and the modification of injection molding parameters improve the impact strength. The presences of an impurity and a compatibilizer have a negative effect on the flame retardant properties of the PC-ABS blend
72

Régénération d’ABS et de PC issus de DEEE sous forme d’alliages de polymères techniques ou de nanocomposites

Barthès, Marie-Lise 17 March 2010 (has links)
Les Déchets d'Equipement Electriques et Electroniques (DEEE) constituent un volume important de déchets dont le constituant majoritaire est l’ABS. C’est pour cela que nous avons travaillé principalement avec des polymères provenant d’un gisement réel (carters d’ordinateurs). Puis, des mélanges ABS/PC ont été élaborés (le PC étant un des constituants d’un gisement de carters), dans le but d’obtenir un matériau avec une résilience au moins équivalente à celle d’un ABS neuf. Même si l’ABS a montré une bonne aptitude à être recyclé seul, après vieillissement et recyclage, sa résilience connaît une chute due à la dégradation de la phase élastomère et à la présence d’ignifugeants. Il est important pour le recyclage de l’ABS et de ses mélanges de séparer les polymères ignifugés de ceux qui ne le sont pas. La voie mélange pour le recyclage de l’ABS par l’ajout de PC a l’avantage de simplifier le tri et de recycler un maximum des polymères présents dans les DEEE. Nous avons tout d’abord réalisé des mélanges ABS/PC neufs pour bénéficier d’une mise en œuvre et d’une composition optimales. L’influence des paramètres du procédé de recyclage (température et vis d’extrusion) et des propriétés des matériaux (taux et viscosité du PC, retardateurs de flamme de l’ABS) sur les propriétés du mélange a été étudiée. Nous avons effectué essentiellement des essais de résistance au choc Charpy et des études morphologiques. Les résultats ont montré qu’une morphologie fibrillaire ou co-continue est favorable à la meilleure résilience des mélanges ABS/PC. Nous avons obtenu pour des mélanges neufs ABS neuf FR/PC neuf réalisés avec 70% d’ABS une résilience supérieure à celle de l’ABS neuf. Mais, à composition égale, ce résultat n’a pas été atteint pour les mélanges majoritaires en ABS recyclé. Souhaitant réaliser des mélanges performants majoritaires en ABS recyclé, la compatibilisation semble nécessaire. Un mélange recyclé majoritaire en ABS, compatibilisé avec du PP-g-MA, est montré plus résilient que l’ABS neuf seul. Toutefois, les compatibilisants ont une efficacité limitée lorsqu’ils sont en présence de retardateurs de flamme ou soumis à un temps de séjour élevé dans la presse à injecter. Nous avons voulu utiliser des nanocharges minérales (montmorillonites), ajoutées en faible quantité, en tant qu'ignifugeants et compatibilisants. Elles se sont avérées inefficaces dans les études préliminaires réalisées. Le choix des nanoargiles minérales doit être optimisé. / WEEE constitute a huge waste volume in which ABS is the major component. So, we focused on polymers from a real deposit (casing of computers); such a deposit contains ABS, PC, PS, ABS-PC. In a first step, recycling of aged ABS was studied. The decrease in the C=C content induces an impact strength drop. Nevertheless, ABS proved to be recyclable given that optimized processing conditions are found. The role of flame retardants was shown to be crucial on the recyclability. Separating polymers with or without flame retardants is the key point of the ABS recycling. However, recycled aged ABS do not recover the impact strength of neat virgin ABS. Then, ABS/PC blends were elaborated in order to obtain a material with an impact strength at least equivalent to the neat ABS. The use of ABS/PC blends for this recycling facilitates the sorting and the utilization of most of WEEE polymers. We first made ABS/PC blends from virgin polymers to have optimal processability and composition. Performing Charpy impact strength tests and morphological studies allowed to evaluate the influence of recycling process parameters (temperature and screw extrusion) and material properties (rate and viscosity of PC and ABS flame retardants). Experimental results indicate that the impact strength of the ABS/PC blends is higher when the morphology is fibrillar or co-continuous. We obtained ABS virgin FR/PC virgin blends (70/30) with an impact strength greater than the neat ABS. But, with equal composition, this result was not reached for the blends. So to achieve reliable blends rich in recycled ABS, compatibilisation is necessary. Recycled ABS/PC blends compatibilised with PP-g-MA is more resilient than the ABS. However, the compatibilising agents have a limited efficiency when they are used in the presence of flame retardants or subjected to a high residence time. Finally, nanoclays were attemptively used as both FR and compatibiliser. Tough they proved uneffective in the very first experiments carried out (the choice of clay need to be optimized).
73

La réduction des impacts environnementaux des technologies de l’information par le droit

Catto, Lionel 08 1900 (has links)
Loin d’être des produits immatériels, les technologies de l’information et de la communication (TIC) ont un réel impact environnemental tout au long de leur cycle de vie. L’Éco-TIC est le point de rencontre entre le développement durable et les TIC. Le droit de l'Éco-TIC est l’ensemble des règles de droit régissant les rapports entre les technologies de l’information et le domaine environnemental. Ce mémoire a pour objectif d’examiner les normes juridiques, notamment en Europe et en Amérique du Nord, qui permettent de limiter l’impact environnemental des technologies de l’information lors des trois phases du cycle de vie des TIC. Tout d’abord, nous nous penchons sur l’étape de la conception des TIC. À cette étape, les réglementations en matière d’écoconception, l’utilisation des terres rares et l’interdiction de l’obsolescence programmée sont particulièrement pertinentes. Ensuite, nous examinons comment les entreprises tentent de réduire la consommation énergétique des TIC lors de la phase d’utilisation, notamment par le biais de la responsabilité sociétale de l’entreprise (RSE). Nous verrons également que les centres de données se multiplient afin de répondre à une demande toujours plus forte. Enfin, nous traitons de la fin de vie des TIC, phase pour laquelle l’Union européenne a créé des directives en matière de réutilisation, réduction et recyclage qui influent sur le plan international. / Information and communication technologies (ICT) are far from being intangible goods and do have an environmental impact during their entire life cycle. Green IT stands at the crossroads of sustainable development and ICT. Green IT law consists of a set of rules governing the relations between information technologies and environment. The purpose of this thesis is to investigate the European and North American legal standards regulating the environment impacts of ICT throughout the three phases of their life cycle. In the first part, the design phase of ICT is examined. At this stage, existing regulations on eco-design, the use of rare earth elements, and the interdiction of planned obsolescence are of particular relevance. The thesis then studies how companies are trying to reduce the use-phase energy consumption of ICT, notably through the Corporate Social Responsability. The issue of the multiplication of data centres, due to an ever-growing demand, is also discussed. In the end, the thesis considers the end-of-life phase of ICT and the directives created by the European Union that affect recycling and waste reduction management at an international level.
74

Responsabilidade compartilhada pelo ciclo de vida do produto na cadeia de resíduos eletroeletrônicos / Product lifecycle shared responsibility in the supply chain of waste electrical and electronic equipment

Mendes, João Múcio Amado 26 March 2015 (has links)
O objetivo do presente trabalho consistiu na análise jurídica da responsabilidade compartilhada pelo ciclo de vida do produto (RCCVP) e suas principais implicações na cadeia de resíduos eletroeletrônicos, no contexto brasileiro da Política Nacional de Resíduos Sólidos, instituída pela Lei Federal n. 12.305/2010 (PNRS). A análise desenvolvida compreendeu os principais deveres relacionados à prevenção de resíduos e à logística reversa, com um enfoque especial na gestão integrada de resíduos eletroeletrônicos. Baseada nos princípios do poluidor-pagador, da cooperação, da prevenção e da precaução, a RCCVP impõe à cadeia de suprimentos a priorização de medidas de prevenção e redução de resíduos por meio de uma concepção ecológica (ecodesign) para produtos e embalagens, bem como pelo reaproveitamento de materiais residuais como insumos, seja em seu próprio ciclo, seja em outros ciclos produtivos, inclusive mediante sistemas de logística reversa e coleta seletiva, estendendo a responsabilidade do berço ao berço e flertando com um modelo econômico circular. Com vistas a desestimular a estratégia da obsolescência planejada de qualidade, a relevante informação sobre o tempo de vida útil de cada produto durável, em especial a dos eletroeletrônicos, deverá ser ampla e obrigatoriamente prestada pela cadeia produtiva, para que os consumidores, uma vez informados e esclarecidos sobre a sua durabilidade objetivamente aferida, tenham condições reais de exercer, na prática, o seu direito e ao mesmo tempo dever de efetuar escolhas de consumo (ou desconsumo), da maneira mais consciente possível, inclusive sob a perspectiva ecológica. No momento, encontra-se em andamento no país o processo de construção de acordo setorial de abrangência nacional para implementação da logística reversa de eletroeletrônicos de uso doméstico, inclusive os provenientes do setor de telefonia móvel. / The aim of this work was the legal analysis of product lifecycle shared responsibility and its implications in the supply chain of waste electrical and electronic equipment (WEEE), within the scope of the Brazilian National Solid Waste Policy, established by Federal Law 12,305/2010. The analysis encompassed the main duties related to waste prevention and reverse logistics, with a particular focus on the WEEE integrated management. Based on the principles of polluter pays, cooperation, prevention and precaution, the product lifecycle shared responsibility requires the supply chain to prioritize waste prevention and reduction measures through an eco-design approach for products and packaging, as well as the reuse of waste materials as inputs, either in its own cycle, or in other production cycles, including through reverse logistics systems and selective collection, extending responsibility \"cradle to cradle\" and flirting with a circular economic model. In order to discourage the planned obsolescence strategy, the relevant information about the lifetime of each durable product, especially of electronics, should be comprehensive and mandatorily provided by the production chain, so that consumers, once informed and enlightened about its durability objectively measured, have actual ability to exercise in practice their right and duty at the same time to make consumer choices (or non-consumption), the most sensible way possible, even from the ecological point of view. Procedure for implementation of consumer WEEE take-back systems with a national scope, through preparation of Sector Agreement, is currently in progress in Brazil, including those from mobile industry.
75

Responsabilidade compartilhada pelo ciclo de vida do produto na cadeia de resíduos eletroeletrônicos / Product lifecycle shared responsibility in the supply chain of waste electrical and electronic equipment

João Múcio Amado Mendes 26 March 2015 (has links)
O objetivo do presente trabalho consistiu na análise jurídica da responsabilidade compartilhada pelo ciclo de vida do produto (RCCVP) e suas principais implicações na cadeia de resíduos eletroeletrônicos, no contexto brasileiro da Política Nacional de Resíduos Sólidos, instituída pela Lei Federal n. 12.305/2010 (PNRS). A análise desenvolvida compreendeu os principais deveres relacionados à prevenção de resíduos e à logística reversa, com um enfoque especial na gestão integrada de resíduos eletroeletrônicos. Baseada nos princípios do poluidor-pagador, da cooperação, da prevenção e da precaução, a RCCVP impõe à cadeia de suprimentos a priorização de medidas de prevenção e redução de resíduos por meio de uma concepção ecológica (ecodesign) para produtos e embalagens, bem como pelo reaproveitamento de materiais residuais como insumos, seja em seu próprio ciclo, seja em outros ciclos produtivos, inclusive mediante sistemas de logística reversa e coleta seletiva, estendendo a responsabilidade do berço ao berço e flertando com um modelo econômico circular. Com vistas a desestimular a estratégia da obsolescência planejada de qualidade, a relevante informação sobre o tempo de vida útil de cada produto durável, em especial a dos eletroeletrônicos, deverá ser ampla e obrigatoriamente prestada pela cadeia produtiva, para que os consumidores, uma vez informados e esclarecidos sobre a sua durabilidade objetivamente aferida, tenham condições reais de exercer, na prática, o seu direito e ao mesmo tempo dever de efetuar escolhas de consumo (ou desconsumo), da maneira mais consciente possível, inclusive sob a perspectiva ecológica. No momento, encontra-se em andamento no país o processo de construção de acordo setorial de abrangência nacional para implementação da logística reversa de eletroeletrônicos de uso doméstico, inclusive os provenientes do setor de telefonia móvel. / The aim of this work was the legal analysis of product lifecycle shared responsibility and its implications in the supply chain of waste electrical and electronic equipment (WEEE), within the scope of the Brazilian National Solid Waste Policy, established by Federal Law 12,305/2010. The analysis encompassed the main duties related to waste prevention and reverse logistics, with a particular focus on the WEEE integrated management. Based on the principles of polluter pays, cooperation, prevention and precaution, the product lifecycle shared responsibility requires the supply chain to prioritize waste prevention and reduction measures through an eco-design approach for products and packaging, as well as the reuse of waste materials as inputs, either in its own cycle, or in other production cycles, including through reverse logistics systems and selective collection, extending responsibility \"cradle to cradle\" and flirting with a circular economic model. In order to discourage the planned obsolescence strategy, the relevant information about the lifetime of each durable product, especially of electronics, should be comprehensive and mandatorily provided by the production chain, so that consumers, once informed and enlightened about its durability objectively measured, have actual ability to exercise in practice their right and duty at the same time to make consumer choices (or non-consumption), the most sensible way possible, even from the ecological point of view. Procedure for implementation of consumer WEEE take-back systems with a national scope, through preparation of Sector Agreement, is currently in progress in Brazil, including those from mobile industry.
76

A plan-do-check-act framework for WEEE and RoHS : a model for implementing WEEE and RoHS by integrating eco-design factors and activities into business operation and strategy.

El-Gomla, Randa A.M. January 2011 (has links)
Eco-design is relatively new and fast growing field of research due to its vital importance to the manufacturing industry and its related environmental issues such as reducing waste, and CO2 emission. A major EU programme relating to the environment is the waste of Electrical and Electronic Equipment (WEEE) directive. The (WEEE) directive specifies ten categories and a voltage range which is up to 1.000 volts AC or 1.500volts DC. The developed framework came for the implementation of Eco-design principles that helps to take into account the adaption of the (WEEE) directive and the restriction of hazard substances (RoHS) used in electrical and electronic equipments. As a result of identify gaps and needs such as a lack of a comprehensive Eco-design framework and the need to integrate it to the normal business operation. In this research the PDCA framework for Eco-design and WEEE directive will be discussed. The framework will encompass all of the Eco-design¿s implementation and integration factors and activities such as WEEE and RoHS directives, Eco-design management, Environmental legislations, Eco-design tools and considerations. The literature review covers the topic of Eco-design¿s related issues, and WEEE and RoHS directives rules. Based on comprehensive questionnaire survey of Eco-design, WEEE and RoHS issues and activities among a sample of environmentally aware companies, statistical analysis is carried out using SPSS software. Then the findings of the survey triangulated with the findings of the literature review formed the basis of the design and implementation plan of the proposed framework
77

協同產品研發生命週期管理之研究-以某個案公司為例 / The Research of Collaborative Product Development Lifecycle Management:A Case Study

粘平吉, Nian,Pyng Jyi Unknown Date (has links)
由微笑曲線理論(施振榮1992年提出)知道企業應該朝高附加價值領域發展,而其中上游智財權(Intelligent Property)、知識經濟(Knowledge Economics)是我國OEM、ODM製造業將生產基地移到大陸後,為避免國內產業空洞化,必須在國內深耕的核心競爭力領域。要強化智財權、知識經濟則必須強化產品研發與創新能力,而產品研發與創新能力的提升必須藉助良好的「協同產品研發生命週期管理解決方案」(Collaborative product development lifecycle management solution) ;但是此解決方案尚在發展初期,不論企業或是個人對於它皆了解不夠,也不知如何利用此解決方案來提升產品研發能力。 因此本研究透過文獻的收集與探討,整理出PLM(Product Lifecycle Management)解決方案的定義、演進,並對PLM解決方案的架構進行探討,再針對市場上PLM解決方案系統廠商所提供的PLM系統產品進行說明,讓有意導入PLM解決方案的公司企業可以參考。另外由於知識管理可以讓PLM系統所收集的產品資料與產品研發經驗與知識得以分享、流通與再創造與加值,因此對於知識管理(Knowledge Management)與PLM的關係進行探討。2003年歐盟立法通過兩大環保法規—WEEE(Waste Electronics and Electrical Equipment)及RoHS(Restriction of Hazardous Substances),要求製造廠商從設計開始即需考慮整個產品生命週期的環境保護觀念,此法規讓產品生命週期觀念有了具體的落實實施,因此本研究亦對綠色環保法規與PLM解決方案的關係進行探討與說明。 本研究為協助企業在導入PLM解決方案前,能夠深入了解PLM解決方案,因此以個案研究方式深入分析個案公司在協同研發產品生命週期中所面臨的問題,並針對這些問題提出PLM系統解決方案的建構策略,也提出PLM系統整合應用架構做為PLM企業策略方法施行的基礎;此PLM系統整合應用架構的特色包括以產品為核心,重視人員、流程及產品資訊;涵蓋從產品觀念的構思開始一直到產品生命結束為止的全生命期間的管理與支援;支援涵蓋跨部門、客戶、設計夥伴與供應夥伴等跨企業間的協同合作。並說明此整合應用架構在協同產品研發生命週期管理中的運作情境,最後再對導入PLM系統解決方案提出規劃重點與想法。 本研究在研究過程中有底下幾點重要發現,特別整理如下: 一、 因為綠色環保法規的規定而使得產品生命週期觀念能落實執行。 二、 PLM是一種企業策略方法,要成功導入必須從人員、流程、資訊科技三方面同時規劃。 三、 由於PLM系統架構的定義不同,且PLM系統廠商所提供的PLM系統解決方案亦有不同功能,企業必須根據自己的需求選擇適當的解決方案。 四、 PLM理念一直不斷變化與延伸,PLM系統已成為製造業不可或缺的系統。 對於後續研究者,本研究建議的未來研究方向如下: 一、 建議對於導入PLM要如何進行變革管理進行研究。 二、 建議對於如何利用知識管理來協助研發創新進行研究。 三、 建議對於PLM解決方案所帶來的協同產品研發績效的影響進行研究。 / Referring to the Smiling Curve Theory (Shih Chen-Rong, 1992), it is realized that enterprise should gradually lead the “High Value-Added” concept to its management system. Since recent years, Taiwan local OEM and ODM factories widely moved their production base to Mainland China, and so in order to avoid domestic industries being emptied, “Intelligent Property” and “Knowledge Economics” must be cultivated deep into our country. On the other hand, prior to strengthen Intelligent Property and Knowledge Economics, the premise is to strengthen the competency of Product Development and Product Innovation. In addition, to enhance the competency of Product Development and Product Innovation must follow by good “Collaborative product development lifecycle management solution”. However, the solution is still at initiation phase, therefore so far as now, either the enterprises or the individuals are not acquainted with it, and also do not know well how to utilize the solution to reinforce the Product Development competency. By means of the concept mentioned above, literatures are collected and investigated by this study to work up the definition and evolution of PLM (Product Lifecycle Management) Solution. In advance, the framework of PLM solution is discussed; and the PLM system, provided by supplier, is introduced by this research as well, in order to allow businessmen, who would like to lead PLM Solution into their organizations, to adopt them as a reference for developing their enterprises. Moreover, considering of that Knowledge Management enables the experience and knowledge of Product Development and Product Information, collected by PLM system, to be shared, circulated, recreated and value-added, the relation between Knowledge Management and PLM system is examined in this study. Also, the relation between the legislated rules of Green Environmental Protection and PLM Solution is researched and reported in response to the two regulations of WEEE (Waste Electronics and Electrical Equipment) and RoHS (Restriction of Hazardous Substances), which were legislated by European Union (EU) in 2003. In accordance with the two statutes, manufacturers are requested to think of the concept of environmental protection for the entire Product Lifecycle, starting from product design begins. For the sake of assisting enterprises in understanding deeply about the PLM Solution, before introducing it into their organization, “case study” access is therefore adopted by the study to analyze in deep the problems on “Collaborative product development lifecycle management solution”, which might be incurred in each individual case. In line with the problems, a constructional strategy for PLM system as well as a framework of the application and integration of PLM system are proposed as a base of executing business strategic approach. Characteristics of the framework of the application and integration of PLM system include “strategic core by product”; “to value personnel, operation flow and product information”; “to manage and support the entire lifecycle from product concept to product lifespan being ended”; “the support covers collaboration between the divisions, customers, designing coworkers, suppliers. In addition, the running situation of this framework, which runs under the “Collaborative product development lifecycle management solution” is presented in the study. In the final part of the research, the key-points and strategies are presented for the proposal of introducing PLM systemic solution. During the researching process, some important conceptions are discovered, and are summarized as follow: 1. Owing to the rules of Green Environmental Protection is legislated, it therefore enables the concept of product lifecycle be executed accurately. 2. PLM is a business strategic approach, so to introduce into enterprise successfully must through a proposal with the factors of personnel, operation flow and information technology simultaneously. 3. Since PLM system has varied system as well as different solution function from different suppliers, enterprises should choose a proper PLM systemic solution based on actual needs. 4. PLM concept varies and extends consecutively, so today PLM has become to the only system for option. Hereunder suggestions from researcher to the latter in future as the researching direction reference. 1. Suggest proceeding study with how to run Reformation Management after the adoption of PLM system. 2. Suggest proceeding study with how to utilize Knowledge Management for assisting in developing innovation. 3. Suggest proceeding study with the subject of “Influence on the results of collaborative product development by PLM systemic solution”.

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