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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.
101

Análise da fundamentação da avaliação do ciclo de vida consequencial. / Analysis of the fundamentals for consequential life cycle assessment.

Muniz, Vivian Carolina Ferreira 01 June 2012 (has links)
O presente trabalho apresenta o resultado da análise sobre o novo foco da ferramenta Avaliação do Ciclo de Vida (ACV): a ACV consequencial. O método convencional da ACV - ACV atribucional - tem sido criticado pelo fato de não suportar decisões baseadas em cenários futuros. Como resposta a esta deficiência, a ACV consequencial surge como uma proposta a um método mais apropriado que avalia consequências ambientais futuras provocadas pelo uso do produto em estudo. O enfoque consequencial apresenta uma abordagem nova da ACV; ainda existem visões distintas e, algumas vezes, divergentes desta abordagem na comunidade internacional da ACV, seja na área acadêmica, seja fora dela. Neste trabalho são apresentadas e discutidas as diferenças, limitações, vantagens e desvantagens entre essas duas ferramentas. Foi possível observar que na realização de um estudo de ACV de um produto ou serviço, a definição do objetivo e escopo do estudo é fundamental para a escolha de qual enfoque da ACV será aplicado. Observou-se, também, que há limitações metodológicas tanto para a ACV atribucional como para a ACV consequencial. No caso da ACV atribucional, por exemplo, há incertezas com relação à escolha subjetiva do método de alocação de co-produtos. Já no caso da ACV consequencial, os resultados podem ser mais sensíveis e mais suscetíveis a incertezas devido às inclusões de estudo da tendência e projeções do mercado para a escolha dos dados e tecnologias marginais, e para a previsão de dados. / The main purpose of this master is to present the analysis results on the Life Cycle Assessment (LCA) new approach: consequential LCA. The conventional method of LCA the attributional approach - has been criticized for not supporting decisions based on future scenarios. In response to this deficiency, the consequential LCA appears as a proposal to a more appropriate method to evaluate future environmental consequences caused by the use of the product under study. As the consequential LCA represents a new approach to LCA, there still are divergent opinions within the LCA international community. In this work, there are shown and discussed the main differences, limitations between these two approaches. It was observed that in conducting an LCA study of a product or service, the definition of the objective and scope of the study is fundamental to the choice of which LCA methodology is applied. It was also observed that there are methodological limitations to both attributional LCA and consequential LCA. In case of attributional LCA, for example, there are uncertainties related to the subjective choice of the allocation method of co-products. In case of consequential LCA, the results may be more sensitive and more susceptible to uncertainties due to inclusions of trend studies and market projections for choosing marginal data and technologies, and for forecast data.
102

Inventário do ciclo de vida do biodiesel etílico do óleo de girassol. / Life cycle inventory of sunflower oil ethylic biodiesel.

Viana, Marcelo Mendes 28 July 2008 (has links)
A Avaliação do Ciclo de Vida (ACV) é uma ferramenta da gestão ambiental que identifica aspectos ambientais e avalia os impactos ambientais de um produto ao longo de todo o seu ciclo de vida. O ciclo de vida considera todas as atividades que vão desde a extração e processamento das matérias-primas, manufatura, transporte, distribuição, uso, reuso, manutenção e disposição final. Através da ACV são obtidas todas as entradas de massa e energia e as respectivas saídas na forma de emissões atmosféricas, efluentes líquidos e resíduos sólidos para cada atividade que compõe o ciclo de vida do produto estudado. No desenvolvimento da ACV, durante a fase de coleta de dados existe uma enorme quantidade de informações que necessita ser coletada. Para sanar essa dificuldade, vêm sendo desenvolvidos bancos de dados de insumos de grande importância os quais possuem características regionais, tornando o estudo mais completo e confiável. A utilização de bancos de dados tem caráter apenas regional, visto que as condições técnicas e ambientais podem variar de uma região para outra. Dependendo da região, a utilização de bancos de dados internacionais tende a distorcer os resultados dos estudos de ACV, conduzindo a resultados não adequados, os quais não representam a realidade da região em estudo. Neste contexto, o Grupo de Prevenção da Poluição do Departamento de Engenharia Química da Escola Politécnica da USP tem desenvolvido estudos que visam à obtenção de Inventários do Ciclo de Vida (ICVs) para auxiliar na construção de um banco de dados brasileiro. O presente estudo, inserido nessa linha de pesquisa, visa à construção do inventário do ciclo de vida do biodiesel etílico do óleo de girassol produzido no Brasil. O biodiesel é um combustível renovável constituído de uma mistura de monoalquilésteres de ácidos graxos de cadeia longa, derivados de óleos vegetais, gorduras animais ou óleos residuais. Neste estudo, definiu-se o sistema de produto para o biodiesel, o qual dividiu-se em subsistemas para facilitar a coleta de dados. Os dados coletados para cada um dos subsistemas foram predominantemente secundários, isto é, obtidos de publicações científicas e bases de dados estrangeiras. No entanto, os dados secundários foram adaptados à realidade brasileira, por meio de informações e considerações que consideraram as condições tecnológicas e de mercado existentes no Brasil. Como resultado verificou-se que 8 dentre todas as etapas do ciclo de vida do biodiesel, a produção dos grãos de girassol é a que demanda mais recursos materiais e energéticos e que provoca a maior quantidade de emissões para o meio ambiente. Deste modo, na produção do biodiesel deve ser dada atenção especial para a produção da oleaginosa, buscando soluções quanto ao seu alto consumo de recursos e emissões para o meio ambiente. / The Life Cycle Assessment (LCA) is a tool of the environmental management which identifies environmental aspects and evaluates environmental impacts of products during its whole life cycle. The life cycle considers all the activities since the extraction and manufacture of the raw materials, transport, distribuction, use, reuse, maintenance and final disposal. Through the LCA are obtained all the inputs of mass and energy and the respective outputs of atmospheric emissions, liquid effluents and solid wastes for every activity of the product life cycle studied. In the development of the LCA, during the phase of data collection there is a vast quantity of information to be collected. To avoid this difficulty, have been in development databases of important inputs, who has regional characteristics, becoming the study more complete and reliable. The database utilization has only a regional character, since the technical and environmental conditions can change in different regions. Depending of the region, the utilization of international database tends to distort the results of an LCA study, leading non adequate results, which don´t represent the reality of the region in study. In this context, de Pollution Prevention Group (GP2) of the Chemical Engineering Department of Polytechnic School of USP have developed studies that aims to obtain Life Cycle Inventories (LCI) to assist the construction of a Brazilian database. The present study is inserted in such line of research and aims to the construction of the sunflower oil ethylic biodiesel LCI made in Brazil. The biodiesel is a renewable fuel, it is constituted of a mix of mono alkyl esters of long chain fatty acids derived of vegetable oils, animal fats or residual oils. In this study was defined the product system to biodiesel, which was divided in subsystems to assist the data collection. The data were collected for each one of the subsystems were in the majority secondary, obtained of scientific publications and foreign databases. However, the secondary data were adapted to the brazilian reality through informations and considerations that take into account the actual brazilian technological and market conditions. As a result it was verified that among all the steps of the biodiesel life cycle, the agricultural production of the sunflower is that one who demands more energetic and materials inputs and is responsible for the majority of the emissions to the environment. In this way, in the biodiesel production should 10 be given special attention to the agricultural production of the oilseed, searching for solutions to its high consumption of inputs and environmental emissions.
103

Inventário do ciclo de vida do metanol para as condições brasileiras. / Life cycle inventory of methanol for brazilian conditions.

Camargo, André Moreira de 02 July 2007 (has links)
A Avaliação do Ciclo de Vida (ACV) é uma ferramenta de gestão ambiental que permite avaliar os aspectos ambientais e impactos potenciais associados a um produto, analisando diversas etapas que vão desde a extração de matérias-primas da natureza que adentram no sistema produtivo (berço), até a disposição do produto final no meio ambiente (túmulo). O conjunto organizado dos aspectos ambientais do produto estudado é chamado de inventário de ciclo de vida, sendo constituído por valores referentes a consumo energético, emissões atmosféricas, efluentes líquidos e resíduos sólidos, entre outros. O Grupo de Prevenção da Poluição (GP2) do Departamento de Engenharia Química da Escola Politécnica da USP, utilizando a metodologia de Avaliação do Ciclo de Vida (ACV), propõe-se ao estudo do desempenho ambiental do biodiesel, combustível produzido a partir de óleos vegetais e álcoois primários de cadeias curtas como o metanol. Portanto, além de contribuir para a execução da ACV do biodiesel, a realização do inventário de ciclo de vida do metanol para as condições brasileiras, proposto neste trabalho, possibilitará a ampliação do banco de dados de ACV no Brasil e no mundo, sendo igualmente utilizado em diversas análises de desempenho ambiental nas quais o metanol esteja inserido. Devido a dificuldade em se coletar dados primários diretamente dos fabricantes, este trabalho adota algumas considerações e hipóteses com o intuito de complementar os dados nacionais não disponíveis por dados secundários, concretizando assim o inventário final. Os resultados do inventário foram confrontados com os resultados oriundos de um modelo simplificado construído a partir da base de dados Ecoinvent, sendo posteriormente comparados e discutidos. Em uma análise simplificada do inventário, podemos concluir que o aspecto ambiental referente ao consumo energético se sobressai perante os demais aspectos devido principalmente em virtude da utilização do gás natural como fonte de energia, refletindo assim em outras categorias de aspectos, como emissões atmosféricas, por exemplo. / Life Cycle Assessment is a tool for environmental management which allows for the assessment of potential impacts and other environmental aspects associated to a product. This is done through the analysis of several steps since the extraction of raw materials from nature which go into the productive system (cradle) to the disposal of the final product in the environment (grave). The organized set of environmental aspects of the product under study is called \"life cycle inventory\", being comprised of values referring to energy consumption, air emissions, liquid effluents and solid residues, among others. The Pollution Prevention Group (Grupo de Prevenção da Poluição - GP2) of the Department of Chemical Engineering of the Polytechnic School, University of São Paulo, Brazil (Departamento de Engenharia Química da Escola Politécnica da USP), making use of Life Cycle Assessment methods (LCA), is set to study the environmental performance of biodiesel, a type of fuel made from vegetal oils and short chain primary alcohols, such as methanol. Therefore, besides contributing to LCA of biodiesel, the inventory of the life cycle of methanol under conditions in Brazil, object of the present study, should allow for the enhancement of Brazilian and worldwide databases, being also useful for several environmental performance analysis in which methanol is inserted. Due to the difficulty in collecting primary data directly from suppliers, the present study assumes some hypothetical considerations with the aim to complement unavailable national data with secondary data, thus completing the final inventory. Results of the inventory were confronted with those of a simplified model constructed from the Ecoinvent database, which led to comparison and discussion. A simplified analysis of the inventory leads to the conclusion that the environmental aspect referring to energy consumption is prominent in relation to other aspects, mainly due to the use of natural gas as energy source, thus reflecting in other classes of aspects, such as air emissions.
104

Avaliação do ciclo de vida de produtos têxteis: implicações da alocação / Life cycle assessment of textile products: implications from allocation

Arduin, Rachel Horta 22 October 2013 (has links)
Os estudos de Avaliação do Ciclo de Vida (ACV) aplicados ao setor têxtil tiveram inicio na década de 1990, sendo realizados principalmente nos Estados Unidos e na Europa. No Brasil, os estudos de ACV aplicados a produtos têxteis utilizando dados nacionais iniciaram nos últimos dois anos. As normas ISO 14040 e 14044 fornecem a estrutura indispensável para a ACV, no entanto, ainda que balizadas por recomendações, certas escolhas metodológicas são realizadas pelo executor do estudo. Na maioria dos ciclos de vida do produto, há pelo menos um processo que tem mais de um produto como saída, e para o qual não é possível coletar dados em separado, sendo necessário aplicar um procedimento de alocação. O presente trabalho teve como objetivo avaliar a influência da aplicação de diferentes procedimentos de alocação no resultado final de um estudo de ACV aplicado à produção de fibras têxteis, através da análise de estudos publicados e da realização de estudo de caso. A revisão dos estudos publicados na literatura baseou-se no método de revisão bibliográfica sistemática. Dentre as publicações que apresentaram o procedimento de alocação selecionado, o que representa apenas 34% dos estudos, a alocação econômica foi realizada em sete estudos, seguido da alocação baseada em critérios físicos (massa) em cinco estudos. No estudo de caso realizado para a produção de 1 tonelada de fibra de algodão no Brasil, a alocação de todo o impacto para a fibra de algodão resultou em 4120kg/CO2 equivalente, enquanto alocando por massa e critério econômico, respectivamente, obteve-se 1627kg/CO2 equivalente e 3419kg/CO2 equivalente. Para a fibra de politereftalato de etileno (PET), observou-se que o método de alocação selecionado altera a fronteira do estudo, que por sua vez impacta no resultado final. Os resultados encontrados no presente estudo reforçam a necessidade de reportar explicitamente as escolhas metodológicas e realizar análise de sensibilidade. / Life Cycle Assessment (LCA) studies applied to the textile sector started in the 1990s, being conducted primarily in the United States and Europe. In Brazil, the LCA studies applied to textiles using national data began in the last two years. The ISO standards 14040 and 14044 provide the necessary structure to the LCA, however, certain methodological choices even that oriented, are made by the analyst. In most product life cycles, there is at least one process that has more than one product as output, and for which it is not possible to collect separate data, being necessary to apply an allocation procedure. This study has aimed to evaluate the influence of applying different allocation procedures in the results of an LCA study applied to textile fibers, through the analysis of published studies and conducting a case study. The review of published studies was performed based on the systematic review method. Among the publications that have presented the allocation procedure selected, which represents only 34% of the studies, economic allocation was performed in seven studies, followed by allocation based on physical criteria (mass) in five studies. In the case study for the production of one ton of cotton fibers in Brazil, allocating the full impact for cotton fiber resulted in 4120kg/CO2 equivalent, while allocating according to mass and economic criteria, respectively, resulted in 1627kg/CO2 equivalent and 3419kg/CO2 equivalent. For the PET fiber, it was observed that the allocation procedure changes the system boundary, and hence the results. The results of this study emphasize the need to explicitly communicate the methodological choices and perform sensitivity analysis on LCA results.
105

Sistemas de certificação ambiental de edificações habitacionais e possibilidades de aplicação da avaliação do ciclo de vida / Sistemas de Certificação Ambiental de Edificações habitacionais e possibilidades de aplicação da Avaliação do Ciclo de Vida

Cardoso, Poliana Figueira 24 March 2015 (has links)
Dada a complexidade da interação entre o construído e o ambiente natural, a ACV (Avaliação do Ciclo de Vida) representa uma abordagem de máxima precisão para analisar os impactos ambientais de todo o edifício. Esta técnica além de considerar os materiais e consumo de energia, deve incluir em sua avaliação a produção e transporte de materiais de construção, e até mesmo o material de reciclagem e gestão de resíduos na fase de desativação. A ACV é a técnica que melhor se enquadra na avaliação de medidas de desempenho ambiental, pois tem a possibilidade de ser integrada aos sistemas de certificação ambiental. Neste contexto, este trabalho tem como objetivo analisar a aplicabilidade da técnica de ACV para os sistemas de CAE (Certificação Ambiental de Edificações) habitacionais no Brasil. Para alcançar este objetivo, utiliza-se a pesquisa exploratória por meio de revisão bibliográfica e documental. Observou-se que a utilização da técnica de ACV nas CAE ocorre em passos iniciais. Todas as CAE já iniciaram pelo menos o pensamento de ciclo de vida como base para conhecimento por parte dos agentes interessados. Algumas CAE possuem iniciativas com propósitos mais adequados ao uso da técnica, como é o caso do BREEAM e do LEED. O BREEAM classifica os materiais escolhidos por meio de abordagem de ACV e o LEED faz a ponderação dos créditos das categorias utilizando o método de caracterização de impacto TRACI. Outra questão relevante é o uso da tecnologia BIM para realizar avaliações de ciclo de vida, o sistema Casa Azul faz menção para no futuro a integração nas fases de projeto. Aponta-se projeções de aplicabilidade da técnica de ACV estar inserida nas categorias relacionadas aos materiais, categoria esta considerada como padrão para avaliação por todas as CAE. / Given the complexity of the interaction between the built and the natural environment, the LCA (Life Cycle Assessment) is a maximum precision approach to analyze the environmental impacts of the entire building. Besides considering the materials and energy consumption, this technique must include in its assessment the production and transport of building materials, and even the material recycling and waste management in the decommissioning phase. LCA is the technique that best fits the evaluation of environmental performance measures, it has able to be integrate with environmental certification systems. In this context, this study aims at analyzing the applicability of LCA technique for ECB systems (Environmental Certification of Buildings) housing in Brazil. To accomplish this, we use the exploratory research through literature and document review. It was observed that use of the CAE technique LCA showed up in the initial steps. All CAE have started at least the thought of life cycle as a basis for knowledge on the part of stakeholders. Some efforts have CAE more suitable for use in technical purposes, such as the BREEAM and LEED. BREEAM classifies chosen materials through LCA approach and LEED is the balance of credits in categories using the method of characterization TRACI impact. Another relevant issue is the use of BIM to perform life cycle assessments, which Casa Azul system makes reference to the future integration into project phases. It points applicability projections of LCA technique is inserted in the categories related to materials, a category regarded as a standard for evaluation by all CAE.
106

Subsídios à avaliação do ciclo de vida do pescado: avaliação ambiental das atividades de piscicultura e pesque-pague, estudo de caso na bacia hidrográfica do rio Mogi-Guaçu / Inputs to the life cycle assessment of the fish from fishery: environmental evaluation of the activities of fish production and fishery, study of case in water basin of the Mogi-Guaçu river

Millani, Thiago José 17 August 2007 (has links)
O desafio de se atingir o desenvolvimento sustentável tem levado os sistemas produtivos buscar um equilíbrio entre os aspectos ambientais, econômicos e sociais. Com relação ao uso dos recursos hídricos, a aqüicultura se mostra, no Brasil, como uma atividade economicamente emergente, mas que precisa considerar os aspectos de sustentabilidade em sua produção. O presente trabalho apresenta como objetivo avaliar os potenciais impactos causados pelas atividades de piscicultura e pesque-pague no corpo hídrico, localizado na região de montante da bacia hidrográfica do rio Mogi-Guaçu. Dentre as metodologias de avaliação de impactos ambientais, pode-se destacar a Avaliação do ciclo de vida (ACV) por seu caráter sistêmico, e por isso é utilizada neste trabalho. Para o desenvolvimento do estudo da ACV, foi utilizado o método Environmental Design of Industrial Products - EDIP, alguns métodos de caracterização hídrica na fase de inventário da ACV e uma avaliação qualitativa da introdução de espécies não nativas em uma região. Os resultados deste trabalho estão estruturados de acordo com a metodologia da ACV, aplicada ao pescado advindo de pesque-pague em estudo de caso localizado na região de montante da bacia hidrográfica do rio Mogi-Guaçu. A unidade funcional adotada é a quantidade de kcal contida em um kg de filé de peixe. A utilização da metodologia da ACV na produção animal permite uma avaliação quantitativa dos principais impactos ambientais gerados ao longo do seu ciclo de vida, permitindo acompanhar o comportamento ambiental de cada unidade de processo. A piscicultura se mostra como a maior consumidora dos recursos naturais não renováveis e, seu efluente apresenta um maior potencial de acidificação, em relação ao pesque-pague. O pesque-pague, por sua vez, se mostra como o maior consumidor dos recursos naturais renováveis e seu efluente apresenta um maior potencial de eutrofização, ecotoxicidade e de toxicidade humana. O consumo de energia elétrica é, praticamente, equivalente por parte das atividades de piscicultura e pesque-pague. Qualitativamente, avaliaram-se os potencias impactos decorrentes da introdução de espécies exóticas e alóctones, diagnosticando as principais espécies comercializadas nos pesque-pague, presentes na bacia hidrográfica do rio Mogi-Guaçu. Portanto, as atividades de piscicultura e pesque-pague apresentam potenciais de impactos ambientais negativos ao corpo hídrico da região e precisam adotar medidas para reduzi-los, tais como, redução do uso de substâncias químicas e melhoria da qualidade dos alimentos dos peixes. / The challenge to reach the sustainable development has taken the production systems to search a balance among the environmental, economical and social aspects. For the hydraulic resources consumption, the water based activities in Brazil show as economically emergent, but need to include the sustainable aspects in the production. The goal of this dissertation is to evaluate the potential impacts in the water caused for the activities of fish production and fishery, located in the region of the water basin of the Mogi-Guaçu river. Among the methodologies of environmental impact assessment, the life cycle assessment (LCA) can be focused, because of its systemic aspect and that\'s why it is applied in this work. For the development of the study of this LCA, the methods used are the Environmental Design of Industrial Products - EDIP, some water characterization methods for the inventory analysis of the LCA and a qualitative analysis of the impacts of the inclusion of fishes which are not from the region studied. The results of this work are structured according the LCA methodology, applied to the fish from fish production and fishery in a study case located at the water basin of the Mogi-Guaçu river. The functional unit is the amount of kcal contained in one kg of filet of fish. The use of the methodology of the LCA in the animal production allows a quantitative evaluation of the main environmental impacts caused by its cycle of life, allowing the monitoring of the environmental behavior of each unit of process. The fish production is the highest consumer of the non renewable resources and its water emissions present the highest potential for acidification. The fishery is the highest consumer of renewable resources and its water emissions present the highest potential for nutrient enrichment, ecotoxicity and of human toxicity. The consumption of electric energy is, basically, equal on the activities of fish production and fishery. Qualitatively, it was evaluated the ecological impacts due to the inclusion of fishes which are not from the region studied. Concluding, the activities of fish production and fishery present negative impact potentials for the water quality and some actions should be done to reduce these impacts, as, chemical consumption reductions and a better quality food for the fishes.
107

Life cycle assessment of the production of edible oil emulsions : comparing a novel process route using aqueously extracted oil-bodies against existing technology

Hetherington, Alexandra Claire January 2014 (has links)
It is estimated that over a third of the diet in the Western world is made up of oils and fats, of which a prominent percentage is in the form of emulsion food products, including milks, creams, yoghurts, margarines, salad dressings, desserts, soups and cheese. Current processing techniques involve the extraction and refining of edible oils using high temperatures and organic solvents, followed by re-encapsulation of the oil, for incorporation into the required emulsion products. The research presented in this PhD thesis was performed within the auspices of the UK Department of Environment, Food and Rural Affairs (DEFRA) funded, Sustainable Emulsion Ingredients through Bio-Innovation (SEIBI) project, which involved collaboration with researchers from the University of Nottingham together with a consortium of industrial partners. SEIBI was initiated to investigate a novel processing route for the production of food-grade rape and sunflowerseed oil emulsions from aqueously extracted oil-bodies. Being less energy and chemical intensive, the novel process offered potential reductions in both greenhouse gas emissions and wider environmental impacts when compared with conventional processing. Using Life Cycle Assessment (LCA) techniques, the environmental burdens of the aqueous oil-body extraction process were determined and compared with those of the existing technology route. To facilitate this, the research focussed on six key objectives, designed to both identify the environmental loads of the systems involved and scrutinise the impact of a number of methodological choices for LCA. These included choice of allocation method, normalisation, scaling issues distinct for novel processes and the extent to which the single-issue LCA variant, carbon footprinting could be used as an environmental indicator for the system. LCAs for four separate categories of product systems were developed encompassing seed oils, mayonnaises, aqueously extracted oil-body materials and mayonnaise-like oil-body emulsions. In addition to generating the environmental profiles required to fulfil the research objectives, the analysis of these models enabled the generation of original knowledge through the quantification of impacts for a range of processes that had either not previously been assessed or for which no published data could be found. The novel process was concluded as having clear potential for improved environmental performance over current technology even in its' pre-optimised, although the methodological choices examined were found to have profound effects on these and other results. Oil-body yield from seed was identified as key for optimisation to further maximise the environmental gains, with modest improvements, well within those theoretically possible being required for the novel process to better the environmental credentials of current technology in all key impact areas. The original outputs from this thesis will be of considerable use to developers involved in the continued advancement of the oil-body extraction technology, together with researchers within the edible oils and emulsions sector. In addition, the methodological outputs will help to inform LCA practitioners and developers in the continuing quest to understand the capabilities and limitations of this powerful analytical tool.
108

Entropy analysis as a tool for optimal sustainable use of biorefineries

Samiei, Kasra January 2007 (has links)
The biorefinery concept is attractive. Increasing international concerns over issuessuch as climate change have led to political as well as social pressures for a shift fromfossil fuels to renewable resources and biomass is one abundant renewable resource.Biomass has the potential of supplying many of the fuels and chemicals which arecurrently dependent on petroleum. Much development is still needed in the field ofbiorefineries and a systematic approach to evaluate and compare process technologiesand to suggest optimizations seems necessary.The objective of this thesis is to develop entropy analysis as a possible evaluation toolfor optimization of biorefinery processes. This is a new application of entropyanalysis which is rarely discussed in the literature. The scientific basis of the entropyanalysis is described and the proposed methodology is explained. The position ofentropy analysis among other system analysis tools such as exergy analysis and lifecycle assessment is discussed along with entropy analysis earlier applications.A case study is introduced which is the IBUS (Integrated Biomass Utilization System)project in Denmark. The idea in IBUS is to integrate the biomass plant with a powerplant to utilize the surplus steam from the power plant for the internal use of thebiorefinery. The suggested method of entropy analysis is applied to this case study tocompare different processes for production of ethanol along with solid biofuel andanimal feed from Danish wheat straw. The evaluation is a gate to gate analysis inwhich production of energy carriers are also included in addition to biorefining ofwheat straw. A parallel life cycle assessment study with equivalent system boundariesis also carried out to compare the results with a conventional environmental systemsanalysis method.The results from the entropy analysis of the IBUS case study show that fermentationof C5 and C6 sugars by yeast is the most efficient process thermodynamically whilefermentation of only C6 sugars by yeast is the least efficient among the three casesstudied. Integration of the biorefinery with a coal fired CHP plant is identified as awise choice by the results of the entropy analysis method.For the IBUS process alternatives investigated in this study, the entropy results andthe LCA results (aggregated environmental load) are in correlation; entropy results areconsistent with weighting results based on two different weighting methods namelyEco indicator 99 and EPS 2000. Entropy generation is also in correlation withproduction cost for the processes analyzed in this evaluation. Another observation isthat cooling in the biorefining process contributes highly in the generation of entropy.This potential improvement option is not surfaced by the LCA conducted.The potential for further investigation and development of the tool is recognizedreflecting on some interesting observations in the results. Improvement of the tool ishighly possible for example by supplementing other implications of entropy inprocess design such as "waste potential entropy" concept which is developed as aneco-toxicity measure. / Uppsatsnivå: D
109

Desenvolvimento de fatores de normalização de impactos ambientais regionais para avaliação do ciclo de vida de produtos no Estado de São Paulo / Development of normalization factors to life cycle assessment in São Paulo state

Silva, André Luiz Ribeiro Tachard da 30 April 2010 (has links)
A normalização é uma importante etapa da Avaliação do Ciclo de Vida, uma vez que fornece uma unidade comum, permitindo a comparação das diferentes categorias de impacto. A referência de normalização mais utilizada considera o impacto das atividades totais da sociedade num certo período de tempo. Estes dados são inexistentes no Brasil para impactos regionais e locais, de forma que este trabalho objetivou iniciar o preenchimento dessa lacuna, com os fatores de normalização para as categorias \"acidificação\" e \"eutrofização\", no estado de São Paulo. Tais fatores foram calculados com base em um inventário das estimativas anuais de aporte ao meio ambiente de substâncias contribuintes para estas categorias, cuja realização possibilitou a análise do estado da arte desses impactos em São Paulo e dos setores responsáveis pela geração das substâncias contribuintes. Conforme esperado, os fatores (ou referências) de normalização encontrados foram diferentes daqueles por hora utilizados no Brasil, baseados em dados europeus. Entre as razões que explicam esta diferença estão a baixa emissão de \'SO IND.X\' devido a matriz energética brasileira, o uso de etanol com combustível e o despejo de esgoto sem tratamento (ou tratamento inadequado). / Normalization is an important step in Life Cycle Assessment as it provides a common unit, allowing the comparison of the different impact categories. The normalization reference most widely used considers the \"background\" impact from the total activities of society in a chosen reference period. These data are inexistent in Brazil for regional and local impacts so that this work aimed to begin filling this lack, first developing normalization factors for the categories \"acidification\" and \"eutrophication\" in the state of Sao Paulo. These factors were calculated from an inventory of the annual load to the environment of substances contributing to these categories; the production of this inventory allowed the analysis of a) the state of the art of these impacts in Sao Paulo and b) the sectors responsible for the generation of contributors. As expected, normalization factors (or references) were different from those currently used in Brazil, based on European data. Among the reasons for this difference are lower \'SO IND.X\' emissions due to the Brazilian energy matrix, the use of ethanol as fuel and disposal of sewage without treatment (or mistreatment).
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Sustainability assessment of wastewater and sludge treatment techniques for removal of compounds from Pharmaceuticals and Personal Care Products (PPCPs)

Tarpani, Raphael January 2017 (has links)
Environmental releases of chemical compounds from Pharmaceuticals and Personal Care Products (PPCPs) are receiving growing attention in the scientific community. Most research suggests that the main pathway for these substances to reach the environment is via Wastewater Treatment Plants (WWTPs) due to the effluents from households, industry and hospitals, which can contain substantial amounts of these compounds. Many of these contaminants are poorly treated in conventional WWTPs and are often discharged into the environment with the effluent and sludge, posing ecotoxicological risks to the wildlife and humans. Therefore, it is necessary to limit their release into the environment by controlling their discharge from WWTPs. This can be achieved by adopting advanced wastewater treatment techniques, currently not used as there are no legislative limits on PPCP compounds. However, as the scientific evidence is growing on their adverse impacts, it is only a matter of time before their advanced treatment becomes compulsory. To help guide future developments and inform policy in this area, this work considered a range of advanced treatment techniques with the aim of identifying the most sustainable options. Adopting a life cycle approach and considering all three dimensions of sustainability (economic, environmental and social), nine technologies were assessed on sustainability: four for WWTP effluent and five for sludge treatment. The advanced wastewater treatment methods considered are: (i) granular activated carbon, (ii) nanofiltration, (iii) solar photo-Fenton, and (iv) ozonation. The sludge treatment techniques comprise: (i) anaerobic digestion of sludge for agricultural application; (ii) sludge composting, also for agricultural application; (iii) incineration; (iv) pyrolysis; and (v) wet air oxidation. They were assessed on sustainability using over 28 indicators, some of which were also used to evaluate the implication of different treatment techniques for the energy-water-food (EWF) nexus. Multi-Criteria Decision Analysis (MCDA) was applied to aggregate the sustainability indicators into an overall sustainability index for each alternative and identify the most sustainable option(s). The results suggest that, among the four techniques considered for advanced effluent treatment, nanofiltration and granular activated carbon have the lowest life cycle environmental impacts. Although not preferable at all operating ranges, they have the lowest burdens and are, overall, most sustainable. The latter also has the lowest impact on the EWF nexus at mean operating parameter, and is the preferred option as the treated effluent can be used for potable water due lower concerns over the presence of PPCPs. However, the results also suggest that, from the ecotoxicological point of view, there is little benefit in using any of the advanced wastewater treatment techniques assessed. This is due to the life cycle ecotoxicological impacts from the treatment itself being similar or even higher than for the effluent released into the environment untreated. For sludge treatments, anaerobic digestion and pyrolysis are environmentally and economically preferable techniques. The former is the best with respect to the EWF nexus due to the recovery of energy and agricultural fertilizers. In relation to social aspects, wet air oxidation is amongst the most desirable for high resource recovery, together with the two former techniques. The heavy metals content in the sludge applied on agricultural soils is a major concern for freshwater ecotoxicity potential, posing risks orders of magnitude higher than PPCP compounds.

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