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Småskalig eller industriell tvätt och hantering av sängkläder inom hotellbranschen : En jämförelse i miljöbelastningJohansson, Erica, Dennisson, Anne January 2018 (has links)
Hotellbranschen är en konstant växande verksamhet och med fler sängar att bädda tillkommer fler lakan att tvätta. Idag kan hotell välja att använda sig utav externa tvätterier som hämtar upp, tvättar och levererar rena sängkläder men kan även välja att själv tvätta sängkläderna lokalt på hotellet. Två olika tvätthanteringssystem som innebär skillnad i både tvätt- och torkprocesserna, något som i sin tur leder till att materialet samt miljön påverkas annorlunda. I en tid då hållbarhet är en prioriterad fråga miljöanpassar många sin verksamhet och för att öka medvetenheten kring det val om hur sängkläder på ett hotell hanteras mest miljöeffektivt, tar denna rapport upp skillnaderna i miljöbelastning då man tvättar industriellt kontra småskaligt. Miljöbelastningen presenteras som koldioxidutsläpp, vatten- och kemikalieförbrukning samt genom skillnader på vävars förslitning inom de olika processerna. Den vanligaste väven för hotellsängkläder inom tvättservice är polycotton medan sängkläder av bomull är mer vanligt vid småskalig tvätt. Testerna utförs därför på en polycottonväv, två olika bomullsvävar samt en väv av både bomull och lyocell för att få ett så brett resultat som möjligt och utforska vad som fungerar. Materialen genomgår 50 tvättar vid industritvätt och 50 tvättar inom en småskalig tvätt för att sedan testa hur de påverkats från otvättat material i cykler om 25 tvättar. Resultaten indikerar på att det finns tydliga skillnader mellan de olika tvätthanteringarna både i hur de påverkar materialen samt ur miljösynpunkt. Då industriell tvätt under en längre period aktivt jobbat mot en mera hållbar affärsmodell och därmed effektiviserat tvättprocessen har det lett till minskad miljöbelastning inom de presenterade faktorerna. Vid leverans till och från tvätteriet är det dock idag fortfarande vanligt att lastbilar används, transportsträckan till hotellet i fråga blir därmed avgörande vid viktning av total miljöbelastning. Det framkommer att sängkläder av polycotton kan ha en likvärdig livslängd som bomull trots sin överlägset höga fysiska slitstyrka på grund av materialets tendens till noppbildning. Hotellbranschen har höga visuella krav på sina textilier och kan därför komma att kassera en vara av polycotton innan det är fysiskt utslitet. / The hotel industry is a constantly expanding business and with several beds to make, more sheets needs to be washed. Today, hotels can choose to use external laundry service that pick up, wash and supply bedding back to the customer. However you can also choose to wash your own bed linen at the hotel. The two different laundry management systems involve differences in both the laundry and the drying processes, which in turn affects the material and environment differently. In a time when sustainability is a prioritized question, people adapt their business to become more eco-friendly. To raise awareness about how bedding in a hotel most efficiently is managed, this report presents and clarifies the differences between industrial versus small scale laundry. The environmental impact is presented as carbon dioxide emissions, water and chemical consumption and how the woven materials handle the different processes. The most common fabric for hotel bedding in the textile service sector is polycotton, while cotton fabric is more common in small-scale laundry. The fabric of test-specimens is chosen to present the widest possible results within a lifelike perspective. Therefore, bedding made of polycotton, a mix between cotton and lyocell and two different cotton fabrics are picked for the tests. The materials undergo 25 and 50 wash cycles for industrial and small-scale laundry before the materials is tested to show how they were affected compared to unwashed fabric. The results indicate that there are distinct differences between the different laundry managements, both in terms of how they affect the material and from an environmental point of view. Since industrial laundry for a long period of time actively has worked towards a more sustainable business model and thus streamlined the washing process, it has resulted in major environmental benefits. However, in the case of delivery to and from the laundry facility, it is still common for trucks to be used. The transport distance to and from the hotel in question therefore becomes crucial when making the choice of the most suitable laundry management.
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Transitioning towards Sustainability : What are we waiting for?Arai, Keigo, Pia, Fernanda, La Ray Armstrong, Kristopher January 2018 (has links)
There is growing consensus that humanity is being confronted with a sustainability challenge of which the severity has never been known to modern man. This pressing situation is demanding solutions and alternatives to change the path of society. At the community level, grassroots movements have emerged around the world as a way of striving to develop local sustainability. This research studies the Transition Movement, a popular, global community-based movement. The aim of this study is to evaluate if a Transition Initiative is effective in moving a local community towards sustainability. The definition of sustainability used in the research is taken from the Framework for Strategic Sustainable Development (FSSD) which comprises of eight sustainability principles (SPs); three ecological SPs and five social SPs. To this end, an analytical-evaluative case study of a single Transition Initiative was conducted in which semi-structured interviews, a survey and document analysis were all use as sources of information. The researchers chose a small-scale Transition Initiative, conducting the case study on the village of Ungersheim, France. The results revealed that the actions of Transition are contributing to progressing Ungersheim towards sustainability, both socially and ecologically. The research also revealed how the Transition is being done and what critical factors allowed for success. The study finally deduces a set of strategic guidelines that may be used for further longitudinal research cross-evaluating Ungersheim to other small-scale community transitions.
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Além da superfície: impactos do desenvolvimento na pesca artesanal de Regência Augusta - ESBicalho, Charlene Sales 29 May 2012 (has links)
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Previous issue date: 2012-05-29 / This study shows how the fishermen of Regency Augusta, district of Linhares-ES, ressignificam fishing and social practices in its work towards large-scale Projects (PGE s) deployed both the rio Doce and maritime space. Want to be investigated from the look of the fishermen as the process of transformation in practice against fishing impacts caused by these investments. The survey was carried out in the community, participating through qualitative methodology, in order to understand the dynamics of artisanal fishermen, their beliefs, Regencia Augusta, values, attitudes and habits. The analysis is based on two directions. On the one hand, the villagers reports and official environmental reports. On the other hand, the description of two meetings of the compensation plan of the Fishing Activity of 4 d Seismic Survey (PCAP), from the view of fishermen. The observation and analysis lead us to the following results: the modification of fishing areas held predominantly in rio to before the sea; insertion of new fishing methods; emergence of new occupations and forms of employment; restriction of fishing area because of seismic surveys carried out in the region for an oil company; conflicts among fishermen / Este estudo mostra como os pescadores artesanais de Regência Augusta, distrito de Linhares ES, ressignificam seus trabalhos pesqueiros e práticas sociais perante Projetos de Grande Escala (PGEs) implantados tanto o rio Doce quanto no espaço marítimo. Pretende-se investigar a partir do olhar dos pescadores como ocorre o processo de transformação na prática pesqueira frente aos impactos ocasionados por esses investimentos. A pesquisa participante foi realizada na comunidade, por meio de metodologia qualitativa, no intuito de compreender a dinâmica dos pescadores artesanais de Regência Augusta, suas crenças, valores, atitudes e hábitos. A análise baseia-se em duas direções. Por um lado, relatos dos moradores e relatórios ambientais oficiais. Por outro, a descrição de duas reuniões do Plano de Compensação da Atividade Pesqueira da Pesquisa Sísmica Marítima 4D (PCAP), a partir da visão dos pescadores. A observação e análise nos levam aos seguintes resultados: a alteração das áreas de pesca antes realizada predominantemente no rio para o mar; inserção de novas modalidades pesqueiras; surgimento de novas ocupações e formas de trabalho; restrição da área de pesca devido pesquisas sísmicas realizadas na região por uma empresa do setor petrolífero; conflitos entre pescadores
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Accumulation by Conservation : Conflicts between aquaculture, protected mangroves and small-scale fisheries in Marismas Nacionales, MexicoSzendro, Enrique January 2018 (has links)
Brackish water ecosystems such as mangroves are among the most biodiverse in the world. The mangroves located in the Gulf of California, Mexico are not an exception. This sea has been studied several times due to its biodiverse coastal ecosystems, one of these sites being “Marismas Nacionales” or National Marshes in the southeast area of the Gulf, which was the focus of the thesis. Local fishing communities have been present in the area since pre-Hispanic times and the area became recognized for their abundant oyster, shrimp, and finfish yields during the XX century. Overexploitation of fisheries in Mexico and national financial crisis opened the door to neoliberal policy and law reforms which affected directly and still affect the subsistence, economy and political power of the fishers in the area. Because of the neoliberal reforms, shrimp aquaculture became an important economic activity in and around the region of Marismas Nacionales by the end of the 1980s. By the 1990s international and national protection, instruments were implemented to revert the damages and pressures created by overexploited fishers, as well as by the new aquaculture practices introduced in the ecosystem, giving Marismas Nacionales the status of the biosphere reserve. The figure of biosphere reserve has reverted the damages in the ecosystem while preserving the communal land inside of it. Nevertheless, since the biosphere reserve does not cover the whole ecosystem, the political boundaries of the biosphere reserve have also been detrimental for the ecosystem and local fishers’ land tenure that remained outside of it, creating an inside/outside effect. The study was done considering the perspectives of the actors involved, mainly the fishers in the area through semi-structured interviews gathered using a snowball method, through second-hand sources collection and literature review. The analysis was done through the political ecology and political economy perspectives to examine the conflicts that were found. The neoliberal laws from the period between 1986 and 1992 have not stopped the depletion of fisheries in the Marismas Nacionales ecosystem. Additionally, with the combination of a lack of formal credit schemes leading to an exploitation by permit holders and middlemen; fishers, in particular, free fishers, in the Marismas Nacionales ecosystem have become vulnerable, as well as scapegoats for the shortcomings of the flawed policies. The most affected fishers inside Marismas Nacionales ecosystem where found outside the limits of the biosphere reserve, demonstrating the deficiencies of the biosphere reserve. Additionally, I claim that conservation instruments and areas around Mexico could potentially become part of a process of primitive accumulation which could end up in privatizing those areas as seen in other places around the world. Moreover, shrimp aquaculture seems to benefit from the conservation policies. Further research is advised in regulatory processes and conservation law schemes, as well as an accurate implementation in the Marismas Nacionales wetlands, that considers all those implicated.
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Pesca artesanal na Baía de Ilha Grande, RJ: conflitos e novas possibilidades de gestão compartilhada / Artisanal fishermen in the Ilha Grande Bay, RJ: conflicts and new possibilities of co-management strategiesFátima Karine Pinto Joventino 30 September 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Esta pesquisa tem por objetivo analisar os conflitos socioambientais envolvendo os pescadores artesanais na Baía de Ilha Grande e as iniciativas institucionais que buscam dar tratamento a esses conflitos de forma compartilhada. Neste sentido, foram consideradas duas iniciativas institucionais: i) o Projeto Desenvolvimento e Gerenciamento dos Sistemas de Gestão da Pesca e Aquicultura na baía de Ilha Grande GPESCA-BIG; e ii) o Termo de Compromisso entre a Estação Ecológica de Tamoios e as comunidades pesqueiras de Angra dos Reis e Paraty. A metodologia envolveu a observação direta da autora em reuniões de conselhos consultivos e grupos de trabalho em unidades de conservação, em especial, os espaços envolvendo a Estação Ecológica de Tamoios, além de apresentações e audiências públicas sobre a proposta de Acordos de Pesca. Utilizou-se também a observação participante em reuniões e oficinas no âmbito do projeto GPESCA-BIG. De forma complementar, a pesquisa se baseou em entrevistas (formais e informais) e análise de documentos diversos elaborados por entidades representativas dos pescadores e demais atores direta e indiretamente envolvidos no conflito. Foram identificadas três grandes grupos de conflitos relacionados aos pescadores artesanais: (1) sobreposição de territórios de pesca/pesqueiros e as áreas protegidas, principalmente aqueles relacionados à ESEC Tamoios; (2) conflitos associados à pesca industrial, identificados pelos pescadores como barcos de fora, e em menor escala, as embarcações de petróleo/gás e do turismo e; (3) conflitos resultantes da falta de regularização/permissionamento da atividade. Em síntese, estes conflitos envolvem políticas de desenvolvimento e de conservação, que se confrontam com o modo de vida tradicional dos pescadores artesanais e caiçaras. Além dos conflitos oriundos das diferentes formas de apropriação do espaço marinho, estes conflitos também estiveram relacionados ao papel paradoxal do Estado no estabelecimento das regras e normas de ordenamento (incluindo-se a fiscalização/monitoramento ambiental), à burocracia e às diversas instituições existentes para tratar de problemas comuns, tornado confuso o gerenciamento da atividade. No que se refere às iniciativas em análise, os resultados demonstram a existência de instituições relativamente bem constituídas na região, com a atuação de órgãos de gestão pública e ambiental nos mais variados níveis: municipal estadual e federal. Além destes, registra-se também a participação da sociedade civil, em especial, dos pescadores artesanais de Paraty e de suas representações, na busca pelo tratamento dos conflitos nos quais estão inseridos. Por outro lado, evidencia-se a falta de articulação e integração entre as políticas e atores, bem como entre as experiências institucionais em curso. Portanto, um dos maiores desafios existentes na implantação de um modo compartilhado de gestão dos recursos pesqueiros na BIG consiste justamente em superar tais limitações institucionais, de maneira que possam promover ações articuladas visando não apenas a conservação integrada do ecossistema, como também a reprodução das práticas tradicionais de pesca e a sua co-existência com os demais tipos de usos / This thesis analyses environmental conflicts involving artisanal fishermen in the Ilha Grande Bay and institutional initiatives aiming at managing such conflicts in shared manners. Two initiatives were considered: i) the project Development of Management Systems of Fisheries and Aquaculture in Ilha Grande Bay GPESCA-BIG; and ii) The Commiment Term between the Tamoios Ecological Station and fishermen communities of Angra dos Reis and Paraty. The methodology comprised the authors direct observation in meetings of the consultation councils and working groups in conservation units, in special, those involving the Tamoios Ecological Station, and also participation in presentations about the proposition of Fishing Agreements and other public hearings. The research also used participative observation in meetings and workshops within the GPESCA-BIG project. Additionally, formal and informal interviews were carried on with relevant actors, and varied documents by entities such as Fishermen Associations, City Governments and City Councils, Ministry of Fisheries and Aquaculture and the Ministry of Environment were consulted. Three major groups of fisheries-related conflicts were identified: (1) overlapping between fishing and protected areas; (2) conflicts associated with large-scale fishing and, to a smaller degree, with oil and gas ships and touristic boats; and (3) conflicts due to the lack of regularization/allowance of the activity. In sum, these conflicts involve both development and conservation policies, which at all times contradict the traditional lifestyle of artisanal fishermen and caiçaras. Besides resulting from different forms of use of the sea, these conflicts are also related to the paradoxical role of the State in setting rules (including supervision and environmental monitoring) to the bureaucracy and to several institutions dedicated to common problems. Regarding the initiatives under analysis, results show that there are relatively well established institutions in the region, comprising public environmental agencies at local, state and national levels. One can also mention the participation of civil society, in special, artisanal fishermen from Paraty and their associations. On the other hand, it is worth highlighting the lack of integration among such policies and agencies/actors, as well as among institutional experiences under way. Therefore, one of the major challenges in the implementation of a strategy of co-management of fishing resources in the Ilha Grande Bay consists in overcoming such institutional shortcomings and adopting articulated initiatives aimed not only at the conservation of the environment, but also the sustainability of traditional fisheries and their co-existence with other kinds of use of the marine resources
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Gouvernance de la santé des plantes et gestion de la biodiversité cultivée - le cas de la santé du haricot gérée par les membres de l'association "Croqueurs de Carottes" / Governance of plant health and management of crop diversity - the case of bean health management among members of the association Croqueurs de CarottesKlaedtke, Stéphanie 28 March 2017 (has links)
De multiples réseaux d'agriculteurs et de jardiniers maintiennent la biodiversité cultivée dans le monde. Leurs pratiques de gestion de la santé des plantes demeurent peu étudiées. La thèse a pour objectif de caractériser l'articulation entre gestion de la biodiversité cultivée et gouvernance de la santé des plantes, se saisissant du cas d'une association d'artisans semenciers, les Croqueurs de Carottes. Elle développe une approche interdisciplinaire et transformatrice pour décrire et comprendre la gouvernance de la santé du haricot par ces acteurs, dans une perspective agroécologique. La théorie de l'acteur-réseau est mobilisée pour situer l'analyse à l’intersection entre approches agronomique et sociologique, reposant sur les données produites par un triple dispositif : expérimentations à la ferme, entretiens semi-directifs et observation participante.Nous qualifions d’in situ l'approche de la santé des plantes des Croqueurs dont l’objectif est de vivre avec les agents pathogènes potentiels. Fondées sur des interactions écologiques entre plantes et terroir, les compétences contribuant à la gestion de la santé des plantes sont distribuées à travers le système de production. Que ce soit en termes de santé ou de biodiversité, un lot de semence est l'expression d'un jeu complexe d'interactions. Il est alors difficile de délimiter des populations de plantes de leur terroir de manière précise. Par conséquent, (i) la santé des plantes ne peut être jugée qu'in situ, dans l'environnement dans lequel elles évoluent et (ii) la gouvernance de la santé des plantes doit être prise e / All over the globe, networks of seed growers are cultivating crop diversity in fields and gardens. Their contribution to the maintenance of this diversity has been studied, but research has widely left aside their management of plant health. The governance of bean health practiced by an association of artisanal seed companies, Croqueurs de Carottes, is approached as a case study in the objective of specifying how management of crop diversity and governance of plant health are articulated. Their concern for the governance of bean health is elucidated from an agroecological perspective, taking an interdisciplinary and transformative approach. Actor-network theory constitutes the backbone of the thesis, situated between agronomy and sociology and drawing upon a threefold research device: on-farm experiments, semi-directive interviews and participant observation.The Croqueurs' approach to bean health is described as in situ approach, in which plant populations are considered healthy if they are able to live with potential plant pathogens and adapt to their growing environments. Relying on ecological interactions, competences of plant health management are distributed throughout the production system. Both for plant health and crop diversity management, a seed lot is determined by a complex system of interactions. A clear boundary distinguishing plant populations from their growing environment cannot be drawn. This implies (i) that plant health must be judged upon in situ in the plants' growing environment and (ii) that the governance of plant health must be considered at the
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Análise da inserção da mineração em pequena escala no planejamento urbano em quatro regiões metropolitanas no estado de São Paulo. / Analysis of incorporating small-scale mining in urban planning in four metropolitan regions in the state of São Paulo.Carlos Henrique Xavier Araujo 03 April 2018 (has links)
O estado de São Paulo é o maior consumidor de agregados minerais do Brasil e está entre os maiores produtores destes bens minerais com uma produção voltada principalmente para construção civil, indústria e agricultura. Tendo-se em vista a relevância da mineração, o presente trabalho tem como objetivo caracterizar como a mineração de pequeno porte de areia e brita tem participado no planejamento urbano em regiões metropolitanas, utilizando como exemplo quatro regiões metropolitanas no estado de São Paulo e o Plano de Desenvolvimento Urbano Integrado (PDUI) de cada uma delas. Neste trabalho foi desenvolvido uma metodologia de análise a partir da consulta a fontes de dados primários e secundários. Os dados primários são do setor mineral do estado de São Paulo que engloba a micro, pequena e média mineração, de 2010 a 2014. Os dados secundários foram obtidos a partir de estudos referentes ao mercado produtor e consumidor das substâncias minerais escolhidas para esta pesquisa. Foi realizado também uma análise de como é a gestão de agregados e políticas públicas na Província de Ontário no Canadá. Como o estudo foi focado no estado de São Paulo, cada um dos PDUIs foi analisado e o resultado é que há pouca interação com a setor mineral e que para a mineração no estado de São Paulo ser exemplo de responsabilidade ambiental, social, econômica é necessário transparência e informação sobre a atividade, além da integração dos atores relevantes. / The state of São Paulo is the largest consumer of mineral aggregates in Brazil and one of the largest producers of mineral goods with a production focused mainly on civil construction, agriculture and industry. Taking into account the relevance of mining, the present study aims to characterize how sand and gravel small-scale mining has been contributing to urban planning in metropolitan regions, taking as example, four metropolitan regions in the state of São Paulo and their Integrated Urban Development Plans (IUDP). In this work, an analysis methodology was developed based on the investigation of primary and secondary data sources. The primary data is from the mineral sector of the state of São Paulo, which covers micro, small and medium-mining from 2010 to 2014. Secondary data was obtained from studies concerning the producer and consumer market of the mineral substances chosen for this research. In addition, an analysis regarding aggregate management and public policies was conducted in the Province of Ontario in Canada. Since the study was focused on the state of São Paulo, each of the IUDPs was analyzed and the result is that there is little interaction with the mineral sector and that for mining in the state of São Paulo to be an example of environmental, social and economic responsibility, transparency and information on the activity is necessary, as well as the integration of the relevant actors.
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Matriz de priorização aplicada à pesquisa mineral na pequena mineração. / Priority matrix applied to mineral exploration in small-scale mining.Ricardo Marcelo Tichauer 01 November 2016 (has links)
Na mineração, grande parte das incertezas e riscos estão associados à caracterização geológica. A adoção das melhores práticas na pesquisa mineral resulta em menor risco e maiores eficácia e eficiência à operação, agregando valor ao empreendimento. No Brasil, em geral, a mineração em pequena escala emprega poucos recursos para a pesquisa mineral, e as melhores práticas são frequentemente ignoradas. Este trabalho aborda a incerteza geológica na mineração e como as melhores práticas de pesquisa mineral podem ser aplicadas na pequena mineração para diminuir riscos e incorporar valor ao projeto. A aplicação da Matriz de Priorização CEBIm em três projetos de pesquisa mineral em pequenos depósitos mostra como essa ferramenta pode ser utilizada de forma simples, prática, rápida e econômica para avaliação do nível de aderência do programa de pesquisa mineral às melhores práticas, que pode indicar a magnitude da incerteza geológica associada ao projeto. / In mining, a large number of uncertainties and risks are associated with geological characterization. The adoption of best practices in mineral exploration results in lower risk and greater effectiveness and efficiency to the operation, adding value to the enterprise. In Brazil, in general, small-scale mining employs little resources for mineral exploration, and the best practices are often ignored. This work addresses the geological risks in mining and how best practices in mineral exploration can be applied in small mining to reduce risks and incorporate value to the project. The application of the CEBIm Priority Matrix in three projects of mineral exploration in small deposits shows how this tool can be utilized in a simple, practical, fast and economical way for assessment of the level of compliance of the mineral exploration program to the best practices, which can indicate the magnitude of geological uncertainty associated with the project.
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Gestão sustentável de recursos e reservas para mineração a pequena escala. / Sustainable management of resources and reserves in small-scale mining.Jacopo Seccatore 11 August 2014 (has links)
Um dos maiores desafios para a mineração no Novo Milênio é a integração da Pequena Mineração no sistema ativo e sustentável de exploração dos recursos minerais. A Pequena Mineração (PM) é uma atividade de mineração definida por baixas despesas e receitas de capital e baixa produtividade. A Mineração Artesanal (MA) é apenas um subconjunto de PM, caracterizada pela mecanização rudimentar, recuperação ineficiente, condições operacionais inseguras e exploração do trabalho. Essa tese pretende demonstrar as seguintes questões de pesquisa: 1) A PM pode ser sustentável? 2) Se sim, como pode ser avaliada? 3) Como a PM sustentável pode ser conseguida na prática? Ao longo da tese é mostrado como a PM pode ser sustentável só saindo da dimensão artesanal. Tal processo depende da sua própria capacidade para operar de forma eficiente. Quando a eficiência operacional é alcançada, a sustentabilidade vem como consequência. Através da eficiência operacional, uma operação de SSM sai da condição artesanal, torna-se sustentável e a sustentabilidade dos meios de subsistência e ambiente circundante é estritamente consequente. Esta tese aborda a questão da PM, de forma quantitativa e não qualitativa. Indicadores básicos são individualizados especificamente para medir as características peculiares de minas artesanais, que as diferenciam das minas industriais. O objetivo desses indicadores é a padronização da avaliação de mina artesanal em termos quantitativos, uma importante ferramenta de pesquisa que não era disponível até agora. A análise desses indicadores permite medir a sustentabilidade potencial de uma mina artesanal, bem como sua atualização ao longo da transformação em uma pequena unidade de mineração industrial. Propõe-se uma nova abordagem para a gestão dos recursos minerais e reservas especificamente para a mineração em pequena escala, a fim de atualizar as minas artesanais em pequenas minas industriais. A abordagem proposta para o cálculo dessa reserva contém dois conceitos principais: uma \"reserva mínima\" necessária para o início do projeto, e a \"replicação\" da operação. A metodologia proposta, aplicada a uma operação de mineração subterrânea de ouro real, mostrou que, no caso em análise, as reservas necessárias para viabilizar a operação de pequena escala são da ordem de grandeza de 1/1000 de que as necessárias para a mineração em grande escala. Este trabalho mostra como uma forma responsável e sustentável de PM é possível e viável, ajudando o desenvolvimento econômico da região onde atua, e criando externalidades positivas, como educação, capacitação, cultura da eficiência e consciência ambiental. / One of the biggest challenges for Mining in the New Millennium is the integration of small-scale mining in the active and sustainable system of exploitation of mineral resources. Small-Scale Mining (SSM) is a mining activity defined by low productivity low capital expenditure and revenues. Artisanal Mining (AM) is just a subset of SSM, characterized by rudimentary mechanization, inefficient recovery, unsafe working conditions and labor exploitation. This thesis intends to answer the following research questions: 1) Can SSM can be sustainable? 2) If so, how can it be evaluated as such? 3) How can sustainable SSM be put into practice? Along the thesis is shown how SSM can be sustainable only coming out of the artisanal dimension. Such a process depends on its own ability to operate efficiently. When operational efficiency is achieved, sustainability comes as a consequence. Through operational efficiency, an operation of SSM comes out of the artisanal condition, it becomes sustainable, and sustainability of surrounding livelihood and environment is strictly consequent. This thesis approaches the issue of SSM in a quantitative and not qualitative way. Basic indicators are individuated specifically to measure the peculiar characteristics of artisanal mines, which differentiate the latter from industrial mines. The purpose of these indicators is the standardization of artisanal mine evaluation on a quantitative basis, an important yet currently unavailable research tool. The analysis of such indicators enables the potential sustainability of an underground artisanal mine to be measured, as well as its upgrade over time towards classification as an industrial small-scale mining unit. It is proposed a new approach for the management of mineral resources and reserves specifically for small-scale mining, in order to upgrade artisanal mines into small-scale industrial mines. The proposed approach to calculate this reserve contains two main concepts: a minimum reserve required for the project start-up and replication to confirm the feasibility of continued operation. The proposed methodology, applied to an actual underground gold mining operation, proved that, in the case analyzed, the reserves required for the small-scale operation are in the order of magnitude of 1/1000 of that required for large-scale mining, when both businesses possess the same level of feasibility. This work shows how a responsible and sustainable form of SSM is possible, achievable and viable, helping the economical development of the area where it operates, and creating positive externalities such as education, capacity building, culture of efficiency and environmental awareness.
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Avaliação de um ciclo de liquefação usando a tecnologia de refrigerante misto para plantas de pequena escala de GNL. / Analysis of a liquefaction cycle using mixed refrigerant technology for LNG small scale plants.Christian Daniel Tacuse Begazo 14 November 2008 (has links)
Este trabalho tem como objetivo analisar a tecnologia do ciclo refrigerante misto para obtenção de gás natural liquefeito (GNL). Nessa tecnologia, o GNL é obtido por meio do seu resfriamento através de um ciclo de refrigeração, cujo fluido refrigerante é formado por uma mistura de diversos componentes. O ciclo de refrigeração é usado para resfriar a corrente de gás natural até as condições criogênicas por meio de um trocador de calor. A determinação da composição ótima dessa mistura de refrigerantes é de suma importância para a correta e eficiente operação da planta. O modelo termodinâmico para o cálculo de equilíbrio de fases dos componentes da mistura refrigerante é o baseado na Lei de Raoult, válido para misturas e soluções ideais. Inicialmente, revisam-se os conceitos de refrigerantes mistos, curvas compostas e o ponto de pinça (pinch point), utilizados na implementação da solução computacional. A aplicação dos modelos de gás e solução ideal influencia nos resultados, mas, não obstante, produz bons resultados como os obtidos no presente trabalho. A operação eficiente do ciclo depende, sobretudo, de três parâmetros principais, quais sejam: vazão da mistura refrigerante, razão de pressões alta e baixa do ciclo de refrigeração e composição da mistura refrigerante. Da análise dos resultados obtidos conclui-se que a alteração nas proporções da composição do refrigerante muda significativamente a forma das curvas composta quente e composta fria, quando comparados à alteração dos níveis de pressão e da vazão do ciclo refrigerante. Entretanto, a operacionalização do ciclo somente ocorre se um dado conjunto de valores daqueles parâmetros satisfaça uma determinada diferença mínima de temperatura, ou ponto de pinça, entre as curvas composta quente e composta fria dentro do trocador de calor. Assim, a operação eficiente do ciclo de refrigeração requer a otimização daqueles três parâmetros operacionais. / This work has the objective of analyzing the technology of mixed refrigerant cycle for obtaining liquefied natural gas (LNG). In that technology, the liquefied natural gas is obtained by means of cooling through a refrigeration cycle, whose fluid refrigerant is formed by a mixture of various components. The refrigeration cycle is used to cool the natural gas stream to cryogenic condition with the use of a heat exchanger. The determination of the optimal composition of this refrigerant mixture is very important for the correct and efficient operation of the plant. The thermodynamic model for the equilibrium phase calculation of the refrigerant mixture is based on the Law of Raoult, which is valid for ideal mixtures and solutions. Initially, the concepts of refrigerant mixture, composite curves and pinch point used in the implementation of the numerical solution were reviewed. The application of ideal-gas and ideal-solution models has influence on the results. Nevertheless, it produces good results as those obtained in the present work. The efficient operation of the cycle depends essentially of three key parameters, which are: refrigerant flow rate, the ratio of high to low pressures of the refrigerant cycle and the mixed refrigerant composition. The results indicated that the composition variation of the refrigerant changes significantly the shape of hot and cold composite curves in comparison to the modification in the pressure levels and the refrigerant flow rate of the refrigerant cycle. However, the process will operate only if a given set of values of those parameters satisfies a minimum temperature difference, or pinch point, between the hot and cold composite curves within the heat exchanger. Thus, the efficient operation of the refrigerant cycle requires the optimization of those three operational parameters.
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