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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.
21

Estudo da separação triboeletrostática de resíduos poliméricos pósconsumo e determinação do limite de contaminação entre PET e PEAD / Study of the triboelectrostatic separation of post-consumer polymer waste and determination of the contamination limit between PET and PEAD

Dayane Taylor de Freitas 19 March 2018 (has links)
A utilização de polímeros tem crescido de maneira significativa em diversos setores da indústria, substituindo materiais como madeira, metais, vidros, entre outros. Entretanto, a constante geração de resíduos poliméricos pós-consumo e seu descarte, tem gerado problemas ao meio ambiente, pois grande parte desses materiais ainda é disposta em aterros sanitários. Assim, a reciclagem de polímeros tem se mostrado uma alternativa mais econômica e ambientalmente correta, já que contribui para minimizar o consumo de recursos finitos, como o petróleo, além de reduzir a emissão de gases tóxicos nos processos de produção e decomposição. No processo de reciclagem, a separação dos polímeros em seus diferentes tipos é uma das etapas mais importantes, pois devido às diferenças nas propriedades químicas e físicas desses materiais, quando misturados e processados, geram produtos finais de baixa qualidade. No Brasil, o método de separação mais utilizado é o de separação manual, porém apresenta grandes desvantagens devido às condições insalubres às quais o trabalhador é submetido e devido a erros de natureza humana cometidos durante o processo. Desta maneira, o objetivo deste trabalho foi estudar diferentes métodos de separação de resíduos poliméricos, dando ênfase na separação triboeletrostática, além de determinar limites de contaminação entre poli (tereftalato de etileno) (PET) e polietileno de alta densidade (PEAD) no produto final reciclado. Foi desenvolvido um dispositivo para separação triboeletrostática de polímeros, o qual se mostrou efetivo na separação de misturas de poli(cloreto de vinila) (PVC)/PET, PVC/acrilonitrila-butadieno-estireno (ABS) e ABS/PEAD, atingindo porcentagens de recuperação maiores que 80% e grau de pureza acima de 90%. No estudo da contaminação entre PET e PEAD, com base na morfologia e propriedades mecânicas apresentadas pelas blendas avaliadas, foi determinado o limite de 3% de contaminação de PET no PEAD, porém não foi possível determinar um limite para a contaminação de PEAD no PET, pois mesmo em pequenas concentrações do contaminante, as blendas apresentaram comportamento instável nos ensaios mecânicos realizados, devido às suas características morfológicas. / The use of polymers has increased significantly in several industrial sectors, replacing materials such as wood, metals, glass, etc. However, the constant generation of plastic wastes and their disposal generate environmental problems, because most of them are disposed to landfill. Thus, polymer recycling seems to be the most economical and environmentally friend alternative, since it contributes to minimize the consumption of non-renewable resources, as petroleum, also reducing the toxic gases emission generated during the production and decomposition processes. The polymer separation in their different types is one of the most important stages of the recycling process, because due to the diferences in their chemical and physical properties, when they are mixed and processed, low quality products are produced. In Brazil, manual separation is the most used method, but it presents great disadvantages, due to the unheathy conditions that the workers are subjected to and the possibility of human errors during the process. The aim of this work was to study different polymer separation methods, emphasizing the triboelectrostatic separation, besides determining contamination limits between polyterephthalate ethylene (PET) and high density polyethylene (HDPE) in the final recycled product. A device for triboelectrostatic separation of polymers was developed, which was effective in the separation of polyvinyl chloride (PVC) / PET, PVC / acrylonitrile-butadiene-styrene (ABS) and ABS / HDPE blends, reaching percentages of recovery greater than 80% and purity above 90%. Contamination between PET and HDPE was evaluated, based on the morphology and mechanical properties presented by the blends prepared. The limit of 3% of PET contamination in the HDPE was determined, but it was not possible to determine the limit for the contamination of HDPE in PET, because even in small concentrations of the contaminant, the blends presented unstable behavior in the mechanical tests performed, due to the morphological characteristics of the blends produced.
22

Reusing Garments : An investigation of influencers to return used garments

Köhler, Maria January 2018 (has links)
Background: A sustainable economy becomes more and more important for most parts of the society. Especially the fashion industry is being criticized for wasting resources and being non-sustainable. Therefore, some textile producers started to implement programs that are aiming on a reuse of garments. Aims of research: The purpose of this research is to discover how customers can be motivated to return unwanted garments, also considering possible hindering factors. To gather this information it is necessary to build a theoretical framework with customer-based theories. The thesis explored how a second hand multi-brand retailer can take active action in encouraging customers to return unwanted textiles. Method: This research was conducted as an inductive qualitative research. The data was gathered through semi-structured interviews with several second hand retailers. The analysis was carried out following the Giogia method. Results: The thesis revealed that the garment disposal behavior is affected by various influences. Influences on the disposal behavior of garment consumers are personal values and believes. The dispose of unwanted garments is often influenced by an ease of handling and the same behavior is followed over the years simply because individuals are used to a certain garment disposal behavior. The largest hindering factors why customers do not return garments to retailers are caused by a lack of information as well as insufficient transparency. This behavior can be affected by second hand retailers by providing improved communication and a motivation to return garments by offering benefits for the customer. The size of the company does not play a major role.
23

Development and Optimization of Near-infrared spectroscopy

Hahlin, Amanda January 2023 (has links)
With the growing demand for sustainable options, the existing sorting capacities are limiting the potential for fiber-to-fiber recycling. With the help of near-infrared spectroscopy (NIRS), automated sorting of textiles with high accuracy is possible due to the easy access for polymer identification. Despite the effectiveness of NIRS, some limitations of the process still limit its full potential. Possible disruptors may interfere with and disturb the identification of polymer identities and compositions in different ways. In the following thesis, additives, treatments, and other environmental factors that may hinder fiber identification are further acknowledged. The key results of the thesis state that stains and factors due to wear and tear are the most common possible disruptors that could be identified from pre-sorted post-consumer end-of-life textiles. Further on, stains of ketchup, deodorant, and oil affect the polymer recognition by lowering the recognized fiber content. Water-repellent coatings on 100 % polyamide woven fabric were not detected correctly according to the NIR scanner, as the stated polymer composition was >90 %. Even though some investigated factors, e.g., material structures, were correctly identified by the NIR scanner, the internal deviation of the knitted polyester structure indicates that porous and loose structures hold the ability to interfere with the detection of polymers. To what extent the operating software has been developed is highly relevant to the outcome of how accurate textile sorting may be.
24

Avaliação da viabilidade de reintegração de resíduos de PET pós-consumo ao meio produtivo / Evaluation of the feasibility of reintegrating post-consumer PET into production

Matos, Tassio Francisco Lofti 11 December 2009 (has links)
Entre os materiais presentes nos resíduos sólidos domiciliares, os resíduos poliméricos pósconsumo representam cerca de 27% do volume total da coleta convencional, segundo Matos (2006), com o agravante da degradação lenta, comprometendo a vida útil dos aterros sanitários e poluindo o meio urbano. Dos resíduos poliméricos, destaca-se o Poli (tereftalato de etileno) PET. O PET é utilizado em embalagens alimentícias e, preferencialmente, no envasamento de bebidas carbonatadas e água mineral com gás. O consumo das embalagens de PET tem sido crescente, o que gera uma presença maior deste resíduo no meio ambiente. A reintegração do PET pós-consumo ao meio produtivo pode ser considerada uma ação mitigatória dos impactos ambientais causados por este resíduo, além de otimizar o ciclo de vida da resina presente na garrafa. A reintegração do PET pós-consumo já é realizada por meio da obtenção de diversos produtos diferentes ao de sua origem (garrafa), com taxas de reciclagens crescentes a cada ano. Entretanto, muitos dos produtos reciclados têm breve vida útil, em decorrência das aplicações que lhes são destinadas. Uma alternativa de vida útil longa para o reciclado de PET seria uma aplicação na construção civil, onde os componentes têm uso de longo prazo, além de ser mais uma opção para suprir o consumo elevado de recursos naturais desta indústria. Neste trabalho foi realizada uma avaliação da viabilidade de reintegração dos resíduos de PET pós-consumo ao meio produtivo, visando os potenciais de disponibilidade da matéria-prima e de propriedades intrínsecas e de desempenho tecnológico do produto reciclado para a indústria da construção civil. A estratégia metodológica da pesquisa compreendeu duas vertentes de avaliação: a gestão dos resíduos e as propriedades e desempenho tecnológico do produto reciclado. O método de avaliação da gestão dos resíduos compreendeu os procedimentos de uma pesquisa exploratória e documental, visando identificar o modelo de recuperação associado às dimensões básicas da logística reversa, assim como o potencial das cadeias de suprimento direto e reverso das garrafas de PET. O método de avaliação tecnológica foi desenvolvido por meio de pesquisa experimental, onde o produto reciclado foi obtido por reciclagem mecânica, compreendendo os processos de revalorização e transformação por injeção, e submetido a diversos ensaios para caracterização das propriedades intrínsecas e o desempenho tecnológico. Destaca-se nos resultados, em relação à avaliação da gestão de resíduos, que a logística reversa das garrafas de PET tem no fator econômico a maior motivação, e, referente à avaliação tecnológica, que os produtos reciclados apresentam perda de desempenho a partir do quarto ciclo de reciclagem, decorrente da degradação das cadeias poliméricas em função das sucessivas reciclagens. A Análise dos resultados permite concluir que existe viabilidade para a reintegração dos resíduos de PET pós-consumo ao meio produtivo da construção civil, visando à aplicação como componente construtivo, considerando as condições de reciclagem adotadas na pesquisa e o potencial de disponibilidade e propriedades de desempenho tecnológico. / Post-consumer polymer materials in household wastes (HW) represent approximately 27% of the total volume of conventional garbage collections, according to Matos (2006). The degradation of these wastes is extremely slow, thus compromising the useful life of sanitary landfills and polluting the urban environment. PET poly(ethylene terephthalate) stands out among these polymer wastes, since it is widely used in food packaging and especially for bottling carbonated drinks and mineral water with gas. The use of PET packaging has been increasing steadily, leading to its ever greater presence in the environment. The reintegration of post-consumer PET into production represents an alternative to mitigate the environmental impacts caused by this waste, as well as to optimize the life cycle of the resin contained in PET bottles. Post-consumer PET is already being recycled into a variety of products for purposes other than their original one (bottles) and recycling rates are increasing yearly. However, many recycled products have a very short service life due to the applications in which they are used. An alternative to lengthen the service life of recycled PET would be its application in civil construction, whose components have long-term uses. This would also represent an additional option to help meet this industrys high demand for natural resources. The present study evaluated the feasibility of reintegrating post-consumer PET into production, in view of the large potential availability of this raw material and the intrinsic properties and technological performance of the recycled product for the construction industry. The methodological strategy of this research comprised two lines of investigation: evaluation of waste management, and evaluation of the properties and technological performance of the recycled product. The evaluation of waste management comprised an exploratory and documental research to identify the product recovery model associated with the basic dimensions of reverse logistics, as well as the potential of the direct and reverse supply chains of PET bottles. The technological evaluation was based on experimental research, which involved the mechanical recycling, since the revaluation processes and transformation for injection of post-consumer PET, followed by several tests to characterize its intrinsic properties and technological performance. With regard to waste management, the results highlight the fact that the reverse logistics of PET bottles is driven mostly by economic factors. From the technological standpoint, the results indicate that recycled PET products show a loss in performance after the 4th cycle of recycling due to the degradation of their polymeric chains in response to successive recycling. An analysis of the results leads to the conclusion that it is feasible to reintegrate post-consumer PET into production, applying it as a component material for civil construction, based on the recycling conditions adopted in this research, the potential availability of post-consumer PET and its properties of technological performance.
25

Destinação de resíduos industriais e pós-consumo: a contribuição das centrais de triagem cooperativadas

Almeida, Francieli Aparecida de 27 February 2014 (has links)
Submitted by Mariana Dornelles Vargas (marianadv) on 2015-05-26T14:22:27Z No. of bitstreams: 1 destinacao_residuos.pdf: 582222 bytes, checksum: f9d4c4f365db39467e9c520303ef0e64 (MD5) / Made available in DSpace on 2015-05-26T14:22:27Z (GMT). No. of bitstreams: 1 destinacao_residuos.pdf: 582222 bytes, checksum: f9d4c4f365db39467e9c520303ef0e64 (MD5) Previous issue date: 2014-02-27 / UNISINOS - Universidade do Vale do Rio dos Sinos / A discussão sobre redução dos resíduos e sustentabilidade tem se mostrado prioritária desde que se percebeu a geração excessiva de novos produtos no mercado e a falta de gerenciamento dos resíduos, principalmente os resíduos sólidos urbanos - RSU. Tais resíduos são provenientes do consumo das famílias e da atividade industrial. Com tal excesso, indústrias têm passado a trabalhar de forma a oferecer alternativas para mudar esse cenário. O objetivo dessa pesquisaé verificar como as centrais de triagem cooperativadas têm contribuído com a reciclagem de resíduos sólidos gerados pelas indústrias. Para realização dessa pesquisa foram utilizados os métodos de revisão bibliográfica e observação não participante. A coleta de dados foi realizada por meio de entrevistas com questionários norteadores e relatórios. Os resultados evidenciaram que as indústrias pesquisadas têm seus processos direcionados em atendimento à redução dos resíduos, ou, ao correto encaminhamento do mesmo, seja para recolhimento da prefeitura (coleta seletiva) ou aterro sanitário controlado. Por outro lado, as centrais de triagem cooperativadas buscam fortalecer seu elo na cadeia logística reversa, processando e reciclando os materiais, formando um ciclo fechado de produção, e pelo que se pode observar necessitam do apoio dos demais atores envolvidos nesse processo, o governo, as empresas privadas e a sociedade em geral para um pleno funcionamento. / The discussion about waste reduction and sustainability has proven a priority since perceived the excessive generation of new products to market and the lack of waste management, mainly municipal solid waste – MSW- provide by household consumption. So, with such excess, the industries are working in order to offer alternatives to change this scenario. The objective of this research is to see how the central cooperative sorting have contributed to the recycling of solid waste generated by industries. For this survey the methods of literature review and participant observation were used. Data collection was conducted through interviews with guiding questionnaires and reports by cooperatives. The results showed that the industries surveyed have directed their processes to reduce waste, or the correct disposal of it, to direct for prefecture (selective collection) or controlled landfill. On the other hand, the recycling cooperatives have seek strengthen its link in the reverse logistics chain, processing and recycling materials , forming a closed production cycle , and need the support of other actors involved in this process, the government, private companies and society in general to a fully functioning .
26

Process simulation and optimisation of thin wall injection moulded components

Mullath, Aravind January 2013 (has links)
Integrally moulded hinges and tension bands are important features in packaging components for plastic closures and their function is critically dependent on the flow induced micromorphology in the hinge section. Polymer characteristics and processing of the hinge also have an influence on the hinge properties obtained. This study is aimed at obtaining interrelationships between polymer characteristics, in-cavity flow, microstructure development and hinge properties, to produce hinges with enhanced functional properties. Three different virgin polypropylene (PP) grades were investigated (homopolymer PP-H, random copolymer PP-RC and impact copolymer PP-IC) and injection moulding simulation was carried out using Moldflow software. In-cavity data acquisition has been carried out for different sets of injection moulding conditions, using high performance transducers and a data acquisition system. A comparison between Moldflow simulation and practical injection moulding data suggests that, for thin wall injection moulded components the real time pressure data are in close agreement during the injection stage. During the packing stage there is some disagreement between these data, since the thickness of hinge and tension band sections are 0.4 mm and 0.5 mm respectively, suggesting that these dimensions are extending the capability of the software. An extensive study using a design of experiments (DoE) approach was carried out on both practical and predictive data. Injection velocity and melt temperature were the most influential factors on the component mechanical properties. From the optical micrographs it is observed that PP-RC has a finer micro-structure compared to PP-H and PP-IC and some micrographs confirm Moldflow simulation results in which hesitation effects are evident, as the flow converges into the thin hinge and tension band sections. PP-clay nanocomposites (PP-CN) were prepared using a twin screw compounder. Transmission electron microscopy (TEM) has shown some evidence of dispersion and exfoliation of the clay particles in the PP matrix. However, X-ray diffraction (XRD) results show a reduction in inter-layer spacing of PPCN s possibly due to clay compaction. The addition of nano-clay however has not resulted in any significant improvements in the mechanical properties of hinges and tension bands. The high degree of molecular orientation induced in the hinge and tension-band sections appears to mask any improvements attributed to the addition of nano-clay. From the reprocessed and post consumer recyclate (PCR) study conducted on hinges and tension bands, it is seen that with an increase in both the re-processing and PCR content there is a decrease in the component strength of around 14%, giving scope to potentially use PCR in future packaging applications. Investigations conducted on colour pigments (violet and green) reveal that the onset of crystallisation for green pigmented mouldings is considerably higher (16°C) than for natural and violet mouldings. Optical micrographs also reveal a finer microstructural texture for green components, indicating a high nucleating capability of the green pigment. Irrespective of the colour, both for hinges and tension bands, the yield stress values were around twice as high as the values quoted in the manufacturer s data sheet for isotropic PP, due to the high levels of molecular orientation in the hinge and tension band sections. In order to industrially validate the findings from the DoE study, commercial closures were produced in industry on a production tool then characterised. In the case of tension bands, there was a good agreement between the results obtained from lab scale and industrial study due to the relatively simple geometry. For hinges this agreement is not so clear. Finally a comparison of mechanical properties of the 3 PP grades shows that PP-H has a higher yield stress compared to PP-IC and PP-RC and yield stress is significantly higher (yield strain values are lower) than values quoted by the manufacturer. The PhD study has confirmed the process conditions that are able to optimise all the interactive effects to improve functional properties in high volume parts in the packaging industry.
27

Logística reserva aplicada aos resíduos de informática : uma investigação nas IFES de Sergipe

Tunes, Elisiane Carra 08 August 2014 (has links)
This study examines how the reverse logistics is being used in the final destination of informatics equipment and supplies post-consumer at the central campi of federal institutions of higher education in Sergipe: Universidade Federal de Sergipe (UFS) and Instituto Federal de Sergipe (IFS). Specifically, it was sought to: a) measure the degree of knowledge of managers responsible for the management of waste electronic equipment on the legal instruments and programs of the Federal Government aimed at managing these wastes; b) describe the process of managing and disposing of waste equipment and computer supplies in federal institutions of higher education of Sergipe; c) determine the similarities and differences in the disposal process of waste equipment and computer supplies between UFS and IFS; d) identify alternatives to improve the management and disposal process of these wastes in the federal institutions of higher education of Sergipe. As methodological aspects, the study is classified as exploratory, descriptive and qualitative, whose research strategy adopted was the study of multiple cases. Regarding the time dimension, the research is cross-sectional. In data collection were applied semi-structured interviews with the managers of the institutions surveyed. Document analysis and direct non-participant observation were used as other sources of evidence. The results revealed that public managers have low degree of knowledge regarding the concepts, legal instruments and federal government programs aimed at disposal of these wastes. Waste management equipment at both institutions have similar procedures. However, the management of post-consumer supplies is distinct, and the final disposition offered to equipment and computer supplies. It was concluded that reverse logistics is still not used at IFES in Sergipe due to the following factors: i) the inapplicability of sectoral agreements between public and private power (they exist but are not yet in force); ii) the refusal by the specific program of the Federal Government to receive donations of equipment and supplies of the institutions surveyed. Among the possible improvements in this process, it can be listed the elaboration of normative instructions, the integrated action of all responsible sectors and the elaboration of an agreement for the Brazilian federal agencies having as a guiding model the Computers Inclusion Programme. / Este estudo analisa a forma como a Logística Reversa (LR) está sendo utilizada na destinação final dos equipamentos e suprimentos de informática pós-consumo dos campi sede nas Instituições Federais de Ensino Superior (IFES) de Sergipe: a Universidade Federal de Sergipe (UFS) e o Instituto Federal de Sergipe (IFS). Especificamente, buscou: a) mensurar o grau de conhecimento dos gestores responsáveis pelo gerenciamento dos resíduos de equipamentos eletrônicos sobre os instrumentos jurídicos e os programas do Governo Federal voltados à gestão desses resíduos; b) descrever o gerenciamento e o processo de disposição final dos resíduos de equipamentos e suprimentos de informática nas Instituições Federais de Ensino Superior de Sergipe; c) verificar as semelhanças e diferenças no processo de disposição final dos resíduos de equipamentos e suprimentos de informática entre a UFS e o IFS; e d) identificar alternativas para melhora no processo de gerenciamento e disposição final destes resíduos nas IFES de Sergipe. Quanto aos aspectos metodológicos, o estudo é classificado como exploratório, descritivo e qualitativo, cuja estratégia de pesquisa adotada foi o estudo de casos múltiplos. Em relação à dimensão tempo, a pesquisa é de corte transversal. Na coleta de dados aplicaram-se entrevistas com roteiros semiestruturados aos gestores das Instituições pesquisadas. Foram utilizadas análise de documentos e observação direta não participante como outras fontes de evidências. Os resultados revelaram que os gestores públicos possuem reduzido grau de conhecimento no que se refere a conceitos, instrumentos jurídicos e programas do Governo Federal voltados ao descarte de resíduos de equipamentos eletroeletrônicos (REEE). O gerenciamento dos resíduos de equipamentos nas duas instituições possuem trâmites semelhantes. Entretanto, a gestão dos suprimentos pós-consumo é distinta, bem como a disposição final oferecida aos equipamentos e suprimentos de informática. Concluiu-se que a logística reversa ainda não é utilizada nas IFES de Sergipe em função dos seguintes fatores: i) a inaplicabilidade dos acordos setoriais entre poder público e privado (eles existem, mas ainda não estão vigorando); ii) a recusa por parte do programa específico do Governo Federal em receber doações de equipamentos e suprimentos das instituições pesquisadas. Dentre as possíveis melhorias neste processo, pode-se elencar a elaboração de instruções normativas, a ação integrada de todos os setores responsáveis e a elaboração de um convênio para os órgãos federais brasileiros tendo como modelo norteador o Programa Computadores para Inclusão.
28

Avaliação da viabilidade de reintegração de resíduos de PET pós-consumo ao meio produtivo / Evaluation of the feasibility of reintegrating post-consumer PET into production

Tassio Francisco Lofti Matos 11 December 2009 (has links)
Entre os materiais presentes nos resíduos sólidos domiciliares, os resíduos poliméricos pósconsumo representam cerca de 27% do volume total da coleta convencional, segundo Matos (2006), com o agravante da degradação lenta, comprometendo a vida útil dos aterros sanitários e poluindo o meio urbano. Dos resíduos poliméricos, destaca-se o Poli (tereftalato de etileno) PET. O PET é utilizado em embalagens alimentícias e, preferencialmente, no envasamento de bebidas carbonatadas e água mineral com gás. O consumo das embalagens de PET tem sido crescente, o que gera uma presença maior deste resíduo no meio ambiente. A reintegração do PET pós-consumo ao meio produtivo pode ser considerada uma ação mitigatória dos impactos ambientais causados por este resíduo, além de otimizar o ciclo de vida da resina presente na garrafa. A reintegração do PET pós-consumo já é realizada por meio da obtenção de diversos produtos diferentes ao de sua origem (garrafa), com taxas de reciclagens crescentes a cada ano. Entretanto, muitos dos produtos reciclados têm breve vida útil, em decorrência das aplicações que lhes são destinadas. Uma alternativa de vida útil longa para o reciclado de PET seria uma aplicação na construção civil, onde os componentes têm uso de longo prazo, além de ser mais uma opção para suprir o consumo elevado de recursos naturais desta indústria. Neste trabalho foi realizada uma avaliação da viabilidade de reintegração dos resíduos de PET pós-consumo ao meio produtivo, visando os potenciais de disponibilidade da matéria-prima e de propriedades intrínsecas e de desempenho tecnológico do produto reciclado para a indústria da construção civil. A estratégia metodológica da pesquisa compreendeu duas vertentes de avaliação: a gestão dos resíduos e as propriedades e desempenho tecnológico do produto reciclado. O método de avaliação da gestão dos resíduos compreendeu os procedimentos de uma pesquisa exploratória e documental, visando identificar o modelo de recuperação associado às dimensões básicas da logística reversa, assim como o potencial das cadeias de suprimento direto e reverso das garrafas de PET. O método de avaliação tecnológica foi desenvolvido por meio de pesquisa experimental, onde o produto reciclado foi obtido por reciclagem mecânica, compreendendo os processos de revalorização e transformação por injeção, e submetido a diversos ensaios para caracterização das propriedades intrínsecas e o desempenho tecnológico. Destaca-se nos resultados, em relação à avaliação da gestão de resíduos, que a logística reversa das garrafas de PET tem no fator econômico a maior motivação, e, referente à avaliação tecnológica, que os produtos reciclados apresentam perda de desempenho a partir do quarto ciclo de reciclagem, decorrente da degradação das cadeias poliméricas em função das sucessivas reciclagens. A Análise dos resultados permite concluir que existe viabilidade para a reintegração dos resíduos de PET pós-consumo ao meio produtivo da construção civil, visando à aplicação como componente construtivo, considerando as condições de reciclagem adotadas na pesquisa e o potencial de disponibilidade e propriedades de desempenho tecnológico. / Post-consumer polymer materials in household wastes (HW) represent approximately 27% of the total volume of conventional garbage collections, according to Matos (2006). The degradation of these wastes is extremely slow, thus compromising the useful life of sanitary landfills and polluting the urban environment. PET poly(ethylene terephthalate) stands out among these polymer wastes, since it is widely used in food packaging and especially for bottling carbonated drinks and mineral water with gas. The use of PET packaging has been increasing steadily, leading to its ever greater presence in the environment. The reintegration of post-consumer PET into production represents an alternative to mitigate the environmental impacts caused by this waste, as well as to optimize the life cycle of the resin contained in PET bottles. Post-consumer PET is already being recycled into a variety of products for purposes other than their original one (bottles) and recycling rates are increasing yearly. However, many recycled products have a very short service life due to the applications in which they are used. An alternative to lengthen the service life of recycled PET would be its application in civil construction, whose components have long-term uses. This would also represent an additional option to help meet this industrys high demand for natural resources. The present study evaluated the feasibility of reintegrating post-consumer PET into production, in view of the large potential availability of this raw material and the intrinsic properties and technological performance of the recycled product for the construction industry. The methodological strategy of this research comprised two lines of investigation: evaluation of waste management, and evaluation of the properties and technological performance of the recycled product. The evaluation of waste management comprised an exploratory and documental research to identify the product recovery model associated with the basic dimensions of reverse logistics, as well as the potential of the direct and reverse supply chains of PET bottles. The technological evaluation was based on experimental research, which involved the mechanical recycling, since the revaluation processes and transformation for injection of post-consumer PET, followed by several tests to characterize its intrinsic properties and technological performance. With regard to waste management, the results highlight the fact that the reverse logistics of PET bottles is driven mostly by economic factors. From the technological standpoint, the results indicate that recycled PET products show a loss in performance after the 4th cycle of recycling due to the degradation of their polymeric chains in response to successive recycling. An analysis of the results leads to the conclusion that it is feasible to reintegrate post-consumer PET into production, applying it as a component material for civil construction, based on the recycling conditions adopted in this research, the potential availability of post-consumer PET and its properties of technological performance.
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Analysis of European post-consumer textile waste for automated sorting

Marin Perez, Maria January 2021 (has links)
The textile industry is linked to several major environmental problems, as a consequence there is an interest at European level to reduce the impact of the industry. In Sweden there are several initiatives to increase the circularity of textile for example by promoting fibre-to-fibre textile recycling. To facilitate this type of recycling the SIPTex project was created to build an industrial automatic textile sorting facility able to offer the high-quality sorted fractions required for fibre-to-fibre recycling. This study developed a quantitative analysis to assess the composition of 1.5 tons of post-consumer textile. The results showed that 52% of the analysed material were high-quality fibre garments - mainly cotton,19% lower quality fibre blends and 28%, uncategorizable garments and items not suited for the sorting facility- as shoes or oversized pieces-. The results will contribute to optimize the material inbound in the SIPTex.
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Estudio experimental a escala de planta piloto del proceso de valorización termoquímica de residuos plásticos urbanos

Gala Buro, Alberto Jesús 18 December 2022 (has links)
Tesis por compendio / [ES] La presente Tesis Doctoral se ha centrado en la demostración de la viabilidad técnica de un proceso de valorización de residuos plásticos de tipo poliolefínico a una escala de planta piloto y en un entorno industrial (TRL 7). Los residuos plásticos objeto del estudio han sido plásticos post-consumo de tipo film segregados de la corriente mezclada de residuos sólidos urbanos (RSU), también usualmente denominada fracción resto o fracción "todo uno". La realización de la presente Tesis Doctoral se enmarca dentro del programa "Ayudas para la formación de doctores en empresas - Doctorados Industriales" del Ministerio de Economía, Industria y Competitividad y está integrada en el marco de una línea de investigación estratégica para la empresa URBASER S.A (empresa líder en gestión de residuos sólidos urbanos en España y con presencia en más de 20 países). Dicha línea estratégica comprende el paso del residuo al recurso bajo el concepto de economía circular. En este contexto, la Tesis Doctoral se centra en el estudio experimental del proceso de pirólisis prestando especial atención a la puesta en marcha y operación de la instalación experimental y a la caracterización de los materiales de partida y de los productos obtenidos. Las principales tareas desarrolladas y resultados obtenidos en esta investigación se han plasmado en una serie de publicaciones científicas que han permitido presentar la Tesis Doctoral en el formato de "Compendio de artículos". En el primer capítulo se aborda la problemática actual de la generación de residuos plásticos urbanos, en particular del plástico tipo film, y se evalúan las diferentes alternativas existentes para su gestión sostenible, estableciendo el interés del estudio realizado y los objetivos perseguidos. El segundo capítulo corresponde a la publicación "Characterization of post-consumer plastic film waste from mixed MSW in Spain: A key point for the implementation of circular economy strategies", en la que se caracterizan las materias primas de interés para el proceso y las que se han utilizado como alimentación en las diferentes pruebas realizadas en la planta piloto. En el tercer capítulo, buscando ofrecer una visión completa de la investigación, se ha prescindido del formato artículo y se ha incluido una breve descripción del sistema experimental y un resumen del proceso que se ha seguido para llevar a cabo la puesta en marcha y operación de la instalación, junto con la metodología experimental empleada y los principales resultados obtenidos. El cuarto capítulo lo integra la publicación "Characterization and distillation of pyrolysis liquids coming from polyolefins segregated of MSW: Using as automotive diesel fuel", en la que se realiza una caracterización de los líquidos de pirólisis obtenidos en la planta piloto a partir de diferentes alimentaciones de plástico (principalmente polietileno de baja densidad) y sus fracciones destiladas, analizando las diferentes opciones para utilizarlos tanto como materia prima para la industria petroquímica como para su empleo como combustible de automoción. En el quinto capítulo se ha recogido la publicación "Simulation-assisted design of a catalytic hydrogenation reactor for plastic pyrolysis fuels", en la que se realiza un análisis de una de las posibilidades de upgrading de los líquidos de pirólisis bajo la perspectiva de la fluidodinámica computacional, estudiando el proceso catalítico de hidrogenación de olefinas mediante un modelo avanzado de un reactor multi-tubular. / [CA] This PhD thesis aims to the development of a polyolefinic plastic valorization process. The technical viability of the process at pilot scale and in an industrial-relevant environment (TRL 7) has been shown. The focus of this work is on post-consumer plastic film originating from household waste and collected as part of mixed municipal solid waste (MSW). The works conducted during the PhD thesis are under the state programme "Ayudas para la formación de doctores en empresas - Doctorados Industriales" funded by the Ministerio de Economía, Industria y Competitividad. These works support the URBASER's strategy (Circular economy: from waste to resource) and are focused on the pilot plant commissioning, start-up and operation, as well as the characterization of feedstocks and products. The main tasks and results have been gathered in a number of papers, which allows this PhD thesis to be submitted in a "papers compendium" format. Chapter 1 deals with the current concerns about the generation of municipal plastic waste. In particular, it looks at the plastic film to evaluate the main available alternatives for sustainable management. This is in order to establish the interest of the study conducted and the objectives pursued. Chapter 2 includes the paper "Characterization of post-consumer plastic film waste from mixed MSW in Spain: A key point for the implementation of circular economy strategies", which comprises some characterizations of the targeted raw materials for the pyrolysis process and of the feedstocks used at pilot plant. Chapter 3, which is not in paper format, completes the previous chapter in order to give oversight of the investigation. It includes a description of the experimental facility, the steps taken to carry out the start-up and operation of the pilot plant, the experimental methodology, and the main experimental results. In this chapter, a developed patent from the pyrolysis process has also been included. In Chapter 4, the product characterization is shown in the paper "Characterization and distillation of pyrolysis liquids coming from polyolefins segregated of MSW: Using as automotive diesel fuel". These characterizations cover the pyrolysis liquids and their distilled fractions obtained from different feedstocks analyzed from two points of view according to the most feasible options: as raw material for the petrochemical industry and as diesel automotive fuel. The paper "Simulation-assisted design of a catalytic hydrogenation reactor for plastic pyrolysis fuels" makes up Chapter 5. This paper explores one of several upgrade options for the pyrolysis liquids consisting of catalytic olefin hydrogenation under a fluid dynamic computational perspective by developing an advanced simulation model for a catalytic multi-tubular reactor. / [EN] La present Tesi Doctoral s'ha centrat en la demostració de la viabilitat tècnica d'un procés de valorització de residus plàstics de tipus poliolefínico a una escala de planta pilot i en un entorn industrial (TRL 7). Els residus plàstics objecte de l'estudi han sigut plàstics post-consum de tipus film segregats del corrent mesclat de residus sòlids urbans (RSU), també usualment denominada fracció reste o fracció "tot un". La realització de la present Tesi Doctoral s'emmarca dins del programa "Ayudas para la formación de doctores en empresas - Doctorados Industriales" del Ministeri d'Economia, Indústria i Competitivitat i està integrada en el marc d'una línia d'investigació estratègica per a l'empresa URBASER S.A (empresa líder en gestió de residus sòlids urbans a Espanya i amb presència en més de 20 països). Aquesta línia estratègica comprén el pas del residu al recurs sota el concepte d'economia circular. En aquest context, la Tesi Doctoral es centra en l'estudi experimental del procés de piròlisi prestant especial atenció a la posada en marxa i operació de la instal·lació experimental i a la caracterització dels materials de partida i dels productes obtinguts. Les principals tasques desenvolupades i resultats obtinguts en aquesta investigació s'han plasmat en una sèrie de publicacions científiques que han permés presentar la Tesi Doctoral en el format de "Compendi d'articles". En el primer capítol s'aborda la problemàtica actual de la generació de residus plàstics urbans, en particular del plàstic tipus film, i s'avaluen les diferents alternatives existents per a la seua gestió sostenible, establint l'interés de l'estudi realitzat i els objectius perseguits. El segon capítol correspon a la publicació "Characterization of post-consumer plastic film waste from mixed MSW in Spain: A key point for the implementation of circular economy strategies", en la qual es caracteritzen les matèries primeres d'interés per al procés i les que s'han utilitzat com a alimentació en les diferents proves realitzades en la planta pilot. En el tercer capítol, buscant oferir una visió completa de la investigació, s'ha prescindit del format article i s'ha inclòs una breu descripció del sistema experimental i un resum del procés que s'ha seguit per a dur a terme la posada en marxa i operació de la instal·lació, juntament amb la metodologia experimental empleada i els principals resultats obtinguts. El quart capítol integra la publicació "Characterization and distillation of pyrolysis liquids coming from polyolefins segregated of MSW: Using as automotive dièsel fuel", en la qual es realitza una caracterització dels líquids de piròlisis obtinguts en la planta pilot a partir de diferents alimentacions de plàstic (principalment polietilé de baixa densitat) i les seues fraccions destil·lades, analitzant les diferents opcions per a utilitzar-los tant com matèria primera per a la indústria petroquímica com per al seu ús com a combustible d'automoció. En el cinqué capítol s'ha recollit la publicació "Simulation-assisted design of a catalytic hydrogenation reactor for plastic pyrolysis fuels", en la qual es realitza una anàlisi d'una de les possibilitats de millora de la calitat dels líquids de piròlisis sota la perspectiva de la fluidodinámica computacional, estudiant el procés catalític d'hidrogenació d'olefines mitjançant un model avançat d'un reactor multi-tubular. / El presente trabajo se ha realizado de manera conjunta en URBASER, S. A. y en el Instituto de Tecnología Química (ITQ) – Universidad Politécnica de Valencia, bajo la dirección de la Doctora Marta Guerrero Álvarez, por parte de URBASER, S. A. y del Doctor José Manuel Serra Alfaro, por parte del ITQ. Los trabajos realizados durante la realización de esta Tesis Doctoral han sido financiados en parte por el Ministerio de Ciencia, Innovación y Universidades a través del programa “Ayudas para la formación de doctores en empresas – Doctorados Industriales” (DI – 16 – 08700) y por el Centro para el Desarrollo Tecnológico Industrial a través de los proyectos “Del residuo al recurso mediante el reciclaje” 3R2020+ (IDI – 20150730) y “Economía circular para la valorización de los residuos plásticos urbanos” CEUS (IDI –20181081) dentro del programa estratégico de Consorcios de Investigación Empresarial Nacional (CIEN). / Gala Buro, AJ. (2020). Estudio experimental a escala de planta piloto del proceso de valorización termoquímica de residuos plásticos urbanos [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/160033 / Compendio

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