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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.
1

The Closed-Loop Endeavour : A Case Study on Barriers and Enhancements of the PET Bottle-to-Bottle Recycling Systems in Germany and Sweden

Bayer, Fabian, Bergmann, Jonas January 2016 (has links)
Problem: The demand of beverages in PET bottles is constantly increasing. In this context, environmental, technological and regulatory aspects set a stronger focus on recycling. Generally, the reuse of recycled material from post-consumer PET bottles in bottle-to-bottle applications is seen as least environmentally harmful. However, closed-loop systems are not widely implemented in Europe. Previous research mainly focuses on open-loop recycling systems and generally lacks discussion about the current German and Swedish systems and their challenges. Furthermore, previous studies lack theoretical and practical enhancements for bottle-to-bottle recycling from a managerial perspective. Purpose: The purpose of this study is to compare the PET bottle recycling systems in Germany and Sweden, analyse the main barriers and develop enhancements for closed-loop systems. Method: This qualitative study employs a case study strategy about the two cases of Germany and Sweden. In total, 14 semi-structured interviews are conducted with respondents from different industry sectors within the PET bottle recycling systems. The empirical data is categorised and then analysed by pattern matching with the developed theoretical framework. Conclusion: Due to the theoretical and practical commitment to closed-loop recycling, the Swedish PET bottle recycling system outperforms the Germany system. In Germany, bottle-to-bottle recycling is currently performed on a smaller scale without a unified system. The main barriers for bottle-to-bottle recycling are distinguished into (1) quality and material factors, (2) regulatory and legal factors, (3) economic and market factors and (4) factors influenced by consumers. The enhancements for the systems are (1) quality and material factors, (2) regulatory and legal factors, (3) recollection factors and (4) expanding factors. Lastly, the authors provide further recommendations, which are (1) a recycling content symbol on bottle labels, (2) a council for bottle quality in Germany, (3) a quality seal for the holistic systems, (4) a reduction of transportation in Sweden and (5) an increase of consumer awareness on PET bottle consumption.
2

PET Recycling – Material and Performance aspects / Återvinning av PET – material och egenskapsaspekter

Höög, Carl January 2021 (has links)
Återvinning och insamling av PET-flaskor startade redan 1994 i Sverige och är en av de grundläggande återvinningsindustrierna.Teknologin har ständigt utvecklas sedan dess och vi har nu nya återvinningsmetoder som kan säkerställa PET-material som uppnår livsmedelskvalitet. Dessutom produktionsmetoder så som Solid-State polymerisation, vilket möjliggör flaska-till-flaska mantrat som genomsyrar Returpack.Med den globala klimatutmaningen vi har framför oss så är intresset i återvinning minskning i användning av fossila bränslen väldigt intressant i många industrier.PET-industrin är en av dessa, där både dryck företag och flasktillverkare vill tillverka flaskor med högre andel återvunnet PET-material. Detta kan redan noteras ute på marknaden, där det finns flaskor tillverkade från 100% återvunnen PET. I denna avhandling har vi undersökt effekten av halten återvunnet material har på både mekaniska och kemiska egenskaper. Effekten av antalet återvinnings-cykler har också blivit undersökt.En labb-version av den återvinningsprocess som används kommersiellt i Sverige av Veolia PET utfördes. Fyra cykler av återvinningsprocessen genomfördes på Virgin PET, vilket resulterade i satserna, krPET-1 till krPET-4. Från varje sats tillverkades hundbens-replikat via formsprutning med olika fraktioner: 25, 50 och 100% återvunnen PET. Alla replikat karakteriserades med instrument och metoder så som dragprovning, FT-IR, DSC och inre viskositet.Från en miljösynpunkt finns det definitiva och redan konstaterade fördelar med en ökning av rPET fraktionen i PET-flaskor. Problem under tillverkningen av replikat ledde till små samplingsstorlekar. Som ett resultat gick det ej att dra några slutsatser från de potentiella nackdelarna som en högre rPET fraktion skulle kunna innebära. / The recycling and collection of PET bottles has a long tradition in Sweden dating back to 1994 and is one of the staple recycling industries.Technology has advanced since then, with new recycling processes to assure food grade certified recycled PET and manufacturing processes such as Solid-State polymerization to enable the bottle-to-bottle mantra. Amidst global warming and climate crisis, the interest in recycling and reducing the use of fossil fuel to manufacture new bottles is ever-growing. As a result, manufacturers and breweries want bottles manufactured with higher fractions of recycled PET, and there are already bottles out on the market made from 100% recycled PET. In this thesis, the effect that the fraction of recycled PET may have on the mechanical and chemical properties of the final product was tested. Also, the effect that several recycling cycles may have on the product was tested.A lab-scale version of the recycling process used commercially in Sweden by Veolia PET were carried out. Four cycles of the process were carried out on virgin PET material, resulting in material batches krPET-1 to krPET-4. Dog bone samples from each recycled batch were manufactured via injection moulding with 25, 50 and 100% rPET fractions. All samples were characterized with various instruments and methods such as FT-IR, Tensile testing, DSC, and intrinsic viscosity testing.From an environmental standpoint, there are clear advantages to an increase in rPET fraction in PET-bottles. Due to issues with manufacturing and the production of samples, only a small sample size was acquired. All the analyses suffered, as a result, making it hard to draw any definite conclusions regarding potential disadvantages with a higher rPET fraction.
3

Avaliação ambiental-econômica do uso da energia no processo de produção de água mineral com aplicação dos conceitos de produção mais limpa

Anschau, Ramon 26 July 2018 (has links)
Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2018-11-30T11:10:44Z No. of bitstreams: 1 Ramon Anschau_.pdf: 3374398 bytes, checksum: 7eaec95d9e0df6af348fa2d967edf4a8 (MD5) / Made available in DSpace on 2018-11-30T11:10:44Z (GMT). No. of bitstreams: 1 Ramon Anschau_.pdf: 3374398 bytes, checksum: 7eaec95d9e0df6af348fa2d967edf4a8 (MD5) Previous issue date: 2018-07-26 / Nenhuma / O aumento no consumo de água mineral mostra a preocupação da população mundial com a compra de produtos mais saudáveis. Porém, devido à pequena margem financeira com a venda do produto, existe maior competitividade entre as empresas e o uso dos recursos para os processos produtivos deve ser conhecido e minimizado, sem impactar na qualidade. Esta pesquisa teve como objetivo, entender e estratificar os consumos de energia nas diferentes etapas do processo de produção de água mineral não carbonatada em embalagens de 500 ml, buscando aplicar melhorias através de conceitos de Produção Mais Limpa (P+L). Conhecer os impactos ambientais potenciais das principais etapas do processo produtivo também foi um dos objetivos do estudo. Para isso, foram detalhados os processos principais e auxiliares através de fluxogramas de entradas e saídas e posteriormente foi realizado o Levantamento de Aspectos e Impactos Ambientais (LAIA). Indicadores de desempenho foram definidos, acompanhados e comparados com a bibliografia no final do estudo, os quais nortearam discussões entre as diferentes áreas da empresa. Todas as ações foram avaliadas técnica e economicamente através de reuniões periódicas e com cálculos de Payback simples, possibilitando conhecer a viabilidade dos possíveis investimentos. No final do estudo foram apresentadas as oportunidades de melhorias implementadas as quais trouxeram ganhos significativos. Após evidenciar que, aproximadamente, 70% do consumo de energia são necessários para a fabricação da embalagem, uma das melhorias sugeridas foi a fabricação de preformas mais leves. Isso tornou o processo 8% mais eficiente energeticamente, além de contribuir com a possibilidade de redução de até 195 toneladas de resina PET por ano, o que trouxe ganhos econômicos, além de diminuir a geração de resíduos sólidos. A redução na pressão de sopragem, outra melhoria implementada, gerou uma redução de 23% no consumo de energia associada à geração de ar comprimido de alta pressão. Melhoria de processo com Payback de 6 meses gerou uma economia anual de cerca de R$37.000,00 considerando a média da tarifa paga pela região sul do Brasil, onde está localizada a empresa. Com a utilização destes métodos, esta pesquisa buscou demonstrar o potencial de aumento de eficiência que estas ferramentas podem trazer para as empresas, trazendo, além de benefícios ambientais e econômicos, fortalecer a continuação de outros estudos de caso com o mesmo enfoque, já que trabalha em todos os níveis hierárquicos da organização. / The increase in mineral water consumption shows the concern of the world population with the purchase of healthier products. However, due to the small financial margin with the sale of the product, there is greater competitiveness among companies and the use of resources for the production processes must be known and minimized, without impacting on quality. The objective of this research was to understand and stratify energy consumption in the different stages of the production process of non-carbonated mineral water in 500 ml packages, seeking to apply improvements through Cleaner Production (P+L) concepts. Knowing the potential environmental impacts of the main stages of the production process was also one of the objectives of the study. For this, the main and auxiliary processes were detailed through input and output flow charts, and the Environmental Aspects and Impacts Survey (LAIA) was subsequently carried out. Performance indicators were defined, monitored and compared with the bibliography at the end of the study, which guided discussions between the different areas of the company. All actions were evaluated technically and economically through periodic meetings and with simple Payback calculations, making it possible to know the feasibility of possible investments. At the end of the study were presented the improvement opportunities implemented which brought significant gains. After evidencing that approximately 70% of the energy consumption is necessary for the manufacture of the packaging, one of the suggested improvements was the manufacture of lighter preforms. This made the process 8% more energetically efficient, besides contributing to the possibility of reducing up to 195 tons of PET resin per year, which brought economic gains, as well as reducing the generation of solid waste. The reduction in blowing pressure, another improvement implemented, generated a 23% reduction in energy consumption associated with the generation of high pressure compressed air. Process improvement with payback of 6 months generated annual savings of about R$37.000,00 considering the average of the tariff paid by the southern region of Brazil, where the company is located. With the use of these methods, this research aimed to demonstrate the potential for increased efficiency that these tools can bring to companies, bringing, in addition to environmental and economic benefits, to strengthen the continuation of other case studies with the same approach, since it works at all hierarchical levels of the organization.
4

Coleta de vespas sociais em estudos de diversidade: estado da arte e otimização do método de armadilhas atrativas

Maciel, Tatiane Tagliatti 22 February 2017 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-05-18T20:10:14Z No. of bitstreams: 1 tatianetagliattimaciel.pdf: 2290219 bytes, checksum: f5018f907a22780f986c6124291c369c (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-19T14:39:48Z (GMT) No. of bitstreams: 1 tatianetagliattimaciel.pdf: 2290219 bytes, checksum: f5018f907a22780f986c6124291c369c (MD5) / Made available in DSpace on 2017-05-19T14:39:48Z (GMT). No. of bitstreams: 1 tatianetagliattimaciel.pdf: 2290219 bytes, checksum: f5018f907a22780f986c6124291c369c (MD5) Previous issue date: 2017-02-22 / Dado o reconhecido papel das vespas sociais no equilíbrio dos ecossistemas é clara a importância de estudos sobre a diversidade desses insetos e, apenas a partir do conhecimento do comportamento das vespas sociais, é possível elaborar metodologias adequadas para a sua coleta. Assim, e tendo em vista a importância de inventários de fauna, o objetivo do presente trabalho foi realizar uma análise detalhada dos estudos de diversidade em vespas sociais conduzidos em Minas Gerais avaliando o uso das armadilhas atrativas. Sabendo da falta de estudos dedicados aos atributos espaciais das espécies de vespas sociais, ou ainda dos métodos utilizados para sua coleta, o trabalho objetivou ainda comparar a atratividade de diferentes variáveis na elaboração de armadilhas atrativas e estimar e analisar em escala local a distância ótima para instalação dessas armadilhas para estudos de diversidade de vespas sociais. A análise detalhada dos estudos de diversidade seguiu os passos propostos pela metodologia de PRISMA para estudos sistemáticos e de meta-análise. A abordagem metodológica incluiu o desenvolvimento de critérios de seleção, definição de estratégias de busca, avaliação da qualidade do estudo e extração de dados relevantes. A parte experimental foi desenvolvida no Jardim Botânico da Universidade Federal de Juiz de Fora que compreende uma área de fragmento de Floresta Estacional Semidecidual Montana, com 84 hectares de extensão, localizado no perímetro urbano de Juiz de Fora, sudeste do estado de Minas Gerais, Brasil. Foi possível observar que Minas Gerais é o Estado com o maior número de estudos, entretanto, as regiões sul e sudeste concentram a maior parte desses estudos, ficando clara a importância do desenvolvimento de pesquisas nas demais regiões, em especial na região norte onde se encontra o Bioma Caatinga. Os experimentos mostraram que devem ser utilizadas garrafas de polietileno tereftalato (PET) de 0,5L como armadilhas atrativas preenchidas com 150mL de suco artificial de manga, goiaba ou maracujá e instaladas a distâncias entre 10m e 150m umas das outras. O trabalho conseguiu otimizar o método de armadilhas atrativas quanto ao tamanho das armadilhas, o tipo de atrativo alimentar utilizado e o número de armadilhas utilizadas em campo. / Considering the recognized role of social wasps in the balance of ecosystems, it is clear the importance of studies on the diversity of these insects and, only from the knowledge of the behavior of the social wasps, it is possible to elaborate adequate methodologies for their collection. Thus, considering the importance of fauna inventories, the aim of this paper was to carry out a detailed analysis of the studies of diversity in social wasps conducted in Minas Gerais, when evaluating the use of attractive traps. Due to the lack of studies dedicated to the spatial attributes of the social wasp’s species, or the methods used for its collection, the study also aimed to compare the attractiveness of different variables in the elaboration of attractive traps. It also aimed to estimate and analyze in local scale the optimal distance for the installation of these traps for studies of social wasp diversity. The detailed analysis of the diversity studies followed the steps proposed by the PRISMA methodology for systematic studies and metaanalysis. The methodological procedure included the development of selection criteria, definition of search strategies, evaluation of study quality and extraction of relevant data. The experimental phase was developed at the Botanic Garden of the Universidade Federal de Juiz de Fora, which comprises a fragment area of Montane Semi-deciduous Forest, with 84 hectares of extension, located in the Juiz de Fora urban area, in the southeast of the State of Minas Gerais, Brasil. It was possible to observe that Minas Gerais is the State with the largest number of studies, however, the south and southeast regions concentrate most of these studies, therefore, it is highlighted the importance of the research development in the other regions, especially in the northern region, where the Caatinga Biome is located. The experiments showed that the traps must be made of bottles of polyethylene terephthalate (PET) of 0.5L, filled with 150mL of artificial juice of mango, guava or passion fruit, and installed at distances between 10m and 150m from each other. The study was able to optimize the method of attractive traps as to the size of the traps, the type of attractive food source and the number of traps used in the field.
5

Stanovení účinnosti zařízení Polymer Separation System Purifier N 1024 / Evaluation of Polymer Separation System Purifier N 1024 device efficiency

Duliková, Michaela January 2014 (has links)
In this Diploma Thesis the recycling of the PET bottles in the company PETKA CZ, a.s. is under focus. Thesis describes the Italian technology AMUT designed for physical recycling of the PET bottles. The primary goal is the quality of the final recycled product, PET flakes, particularly in the context of undesirable admixtures such as PVC, other polymers and impurities. Due to the deteriorating quality of the PET flakes the equipment Polymer Separation System Purifier N 1024 has been tested, which had significantly reduced admixtures in PET flakes. As it turned out, the current procedures for solving problems with the PET flakes quality are no longer sufficient.
6

Síntese de catalisadores utilizando garrafa pet para a produção de biodiesel. / Synthesis of PET bottle using catalysts for biodiesel production

Souza, Juliana Kelly Dionízio de 17 September 2012 (has links)
Made available in DSpace on 2015-05-14T13:21:19Z (GMT). No. of bitstreams: 1 ArquivoTotal.pdf: 4834263 bytes, checksum: 9a0661df73e9955af44f0e37d15bf261 (MD5) Previous issue date: 2012-09-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The heterogeneous catalysis is a promising alternative to solve the environmental problems found in homogeneous catalysis, because it allows the continuous use of the catalyst until its deactivation and minimizes the generation of effluents. Thus, this work aims to synthesize, optimize and evaluate the activity of heterogeneous catalysts, using PET bottles as a starting material in the synthesis of the active phase and SiO2 as catalyst support for the transesterification reaction of soybean oil. The the catalysts were obtained by a impregnating reaction using methanol. The active phase, the catalysts and catalyst support were characterized by X-ray diffraction (XRD), infrared (IR), Raman spectroscopy, scanning electron microscopy (SEM) and EDS, thermal analysis (TG) and measurement surface area (BET). The biodiesels has been synthesized using a molar ratio of 1:9 (soybean oil: methanol), 0,1 g of active phase as catalyst (room temperature) and 1,2 g of the catalysts synthesized at 75 °C, where its kinematic viscosities were measurements. All catalysts were effective in the synthesis of biodiesel because the viscosity reduction of soybean oil used was very significant, indicating that may have occurred the transesterification process, among all biodiesels synthesized the catalyst that stood out was the 30%-K2CO3/70% SiO2, which was obtained greater viscosity reduction at a lower reaction time. The quality tests were made for 1h Bio-30%, which proved be inside the parameters established by the Agência Nacional de Patróleo (ANP). The experiment reuse of the catalyst used in the synthesis of Bio-1h 30%, showed that the catalytic activity is reduced due to possible leaching phenomenon, then preliminary studies have been proposed to study the possible leaching of the active phase. / A catálise heterogênea é uma alternativa promissora para resolver os problemas ambientais encontrados na catálise homogênea, pois permite o uso continuo do catalisador até sua desativação e minimiza a geração de efluentes. Neste sentido, este trabalho visa em sintetizar, otimizar e avaliar a atividade de catalisadores heterogêneos, utilizando a garrafa PET pós-consumo como matéria prima na síntese da fase ativa e SiO2 como suporte catalítico para a reação de transesterificação com óleo de soja. Os catalisadores foram obtidos pela o método de impregnação utilizando o metanol como solvente. A fase ativa, os catalisadores e o suporte catalítico foram caracterizados por difração de raios-X (DRX), espectroscopia na região do infravermelho (IV), espectroscopia Raman, microscopia eletrônica de varredura (MEV) e EDS, análise térmica (TG), e medida de área superficial (BET). Os biodieseis foram sintetizados utilizando uma razão molar de 1:9 (óleo de soja: metanol), 0,1 g da fase ativa como catalisador a temperatura ambiente e 1,2 g dos catalisadores sintetizados a 75 °C, onde suas viscosidades cinemáticas foram medidas. Todos os catalisadores foram efetivos na síntese do biodiesel, pois promoveu a redução de viscosidade do óleo de soja utilizado, no qual mostrou um indicativo que a reação de transesterificação ocorreu, dentre todos os biodieseis sintetizados o catalisador que mais se destacou foi o 30%-K2CO3/70%-SiO2, onde obteve-se a maior redução de viscosidade com um menor tempo reacional. Os testes de qualidade foram feitos para o Bio 1h-30%, o qual mostrou estar dentro dos parâmetros estabelecidos pela Agência Nacional de Petróleo (ANP). O experimento de reuso do catalisador utilizado na síntese do Bio 1h-30%, mostrou que a atividade catalítica é reduzida devido ao possível fenômeno de lixiviação, então estudos preliminares foram propostos para estudar a possível lixiviação da fase ativa.

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