998 resultados para Método de estudo de impacto ambiental


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One of the most widespread renewable energy sources in Brazil is ethanol, from sugarcane, therefore, the sugar and alcohol sector is expanding, with positive impacts for the economy of the country. Sugar cane was introduced in Brazil as a crop during its colonization, for the production of sugar, and put the country in the global scenario. The expansion of this crop occurred in the seventies, to reduce the reliance in fossil energy sources and to stimulate the development of the agricultural activity. Thus, the federal government has promoted the sugar cane crop and the production of ethanol as a fuel. However, it is important to minimize possible impacts that the crop may cause to the environment. Sugar cane has expanded in the frontiers of the mesoregion of Triângulo Mineiro and Alto Paranaíba-MG, and, in this perspective, the agroindustrial complex known as Companhia Energética Vale do São Simão Ltda., with the Mill located in the county of Santa Vitória, Minas Gerais, was adopted to evaluate the environmental impacts caused by the sugarcane in the area of influence of the mill. The mill has a polygonal area corresponding to 53,525.20 hectares, and for its establishment a Study and Report of Environmental Impacts (EIA/RIMA) was presented, as required as an environment protection instrument by the Environment National Policy (Law nº 6.938/81), and detailed by the Resolution CONAMA nº 01/1986. These studies pointed that native vegetation fragments in the Area of Influence of the Mill, before its implantation, corresponded to approximately 20.7% of the area. Therefore, this study evaluated the impacts of the installation of Usina Vale do São Simão, between 2007 and 2012, determining its reflex on the environmental regularization of the farms, and the vegetation fragments existing in the area, in the recovery and recomposition of areas defined as Legal Reserve and Permanent Preservation. Previous studies of the area were analyzed, soil use and occupation was mapped for the years 2007 and 2012, and the areas of permanent preservation and native vegetation fragments were marked. In general, there was a decline in native vegetation coverage in the period, although it cannot be stated that such reduction was a direct effect of the milling activity. Therefore, the legal requirement of preserving such areas was not capable of bringing the positive effects of protection and recovery as demanded by the Law, highlighting that the current legislation was not enough to protect such areas.

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Perturbation of natural ecosystems, namely by increasing freshwater use and its degradative use, as well as topsoil erosion by water of land-use production systems, have been emerging as topics of high environmental concern. Freshwater use has become a focus of attention in the last few years for all stakeholders involved in the production of goods, mainly agro-industrial and forest-based products, which are freshwater-intensive consumers, requiring large inputs of green and blue water. This thesis presents a global review on the available Water Footprint Assessment and Life Cycle Assessment (LCA)-based methods for measuring and assessing the environmental relevance of freshwater resources use, based on a life cycle perspective. Using some of the available midpoint LCA-based methods, the freshwater use-related impacts of a Portuguese wine (white ‘vinho verde’) were assessed. However, the relevance of environmental green water has been neglected because of the absence of a comprehensive impact assessment method associated with green water flows. To overcome this constraint, this thesis helps to improve and enhance the LCA-based methods by providing a midpoint and spatially explicit Life Cycle Impact Assessment (LCIA) method for assessing impacts on terrestrial green water flow and addressing reductions in surface blue water production caused by reductions in surface runoff due to land-use production systems. The applicability of the proposed method is illustrated by a case study on Eucalyptus globulus conducted in Portugal, as the growth of short rotation forestry is largely dependent on local precipitation. Topsoil erosion by water has been characterised as one of the most upsetting problems for rivers. Because of this, this thesis also focuses on the ecosystem impacts caused by suspended solids (SS) from topsoil erosion that reach freshwater systems. A framework to conduct a spatially distributed SS delivery to freshwater streams and a fate and effect LCIA method to derive site-specific characterisation factors (CFs) for endpoint damage on aquatic ecosystem diversity, namely on algae, macrophyte, and macroinvertebrates organisms, were developed. The applicability of this framework, combined with the derived site-specific CFs, is shown by conducting a case study on E. globulus stands located in Portugal as an example of a land use based system. A spatially explicit LCA assessment was shown to be necessary, since the impacts associated with both green water flows and SS vary greatly as a function of spatial location.

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As fusões e aquisições (F&A) são operações estratégicas usadaspor empresas para fortalecer e manter a sua posição no mercado. Estas são vistas por muitos como uma forma relativamente rápida, flexível e eficiente de expandir para novos mercados, incorporar novas tecnologias e inovar. Sem essas qualidades, as empresas acreditam que é praticamente impossível ser competitivo na economia global de hoje. No entanto, o seu sucesso não é de forma alguma garantido. Perante esta incerteza de que tudo corra de forma vantajosa, o presente trabalho pretende avaliar através do estudo do impacto do processo de fusão ou aquisição o desempenho das empresas portuguesas. Procedemos a duas metodologias para chegar a uma conclusão sobre este estudo. Primeiramente foi feito o cálculo e análise de indicadores económico-financeiros antes e depois da realização da F&A e em segundo, uma análise do efeito de notícias boas e más referentes ao anúncio da mesma através da metodologia das janelas de eventos para cinco casos de F&A ocorridos em Portugal, sendo assim o método de análise baseado em casos de estudo. Foi possível verificar, regra geral, um desempenho superior das empresas adquirentes após o processo de F&A. Concluiu-se que os mercados reagem de forma distinta às boas e às más notícias e que o investidor é alvo de alterações de comportamento em termos de sentimento antes e após o anúncio. Deste modo a análise é sensível à distinção por tipos de notícias, sendo necessária a sua correta classificação. Por último, os resultados parecem indiciar que as reações do mercado acionista aos processos de F&A estão dependentes da situação económico-financeira corrente, resultado que merecerá futuramente uma análise posterior mais cuidada e profunda.

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This thesis describes the theoretical, methodological and programmatic proposal for a multifamily residential building located in the urban expansion area of Parnamirim/RN, inserted in the program Minha Casa Minha Vida and level of energy efficiency "A", as the RegulamentoTécnico de Qualidade (RTQ-R/INMETRO) for residential buildings. The development project initially consists of procedures as the study of theoretical, architectural programming and cases studies. With the delimitation of a field solution, situated between the reference and the context, proposals are studied to determine the solution and architectural detailing of the proposal. The architectural program was built based on the method of Problem Seeking (Peña and Parshall, 2001) and research has highlighted aspects of reducing the environmental impact and of the program Minha Casa Minha Vida , among others. The design process was characterized by the incorporation of aspects reviewed and programmed, seeking them compatible and have an economically viable building, socio-spatial quality and energy efficient. The results show that it is possible to obtain a building that meets the constraints of the program that provides housing and energy efficiency level A - and many other environmental qualities and constructive, particularly through architectural design

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As estruturas de solo reforçado com geossintéticos são normalmente constituídas por solos granulares com boas propriedades físicas e mecânicas. O uso de apenas este tipo de solos pode proporcionar o aumento, por vezes insustentável, do custo da execução das estruturas e o aumento do seu impacto ambiental. Deste modo, as estruturas de solo reforçado perdem a sua vantagem competitiva em relação a outros tipos de estruturas (muros de betão, muros de gravidade, muros de gabiões, etc.). Para resolver este problema podem ser utilizados outros tipos de solos (solos locais, finos, com propriedades físicas e mecânicas piores mas, no entanto, mais baratos) para a execução deste tipo de estruturas. De forma geral, com este estudo pretendeu-se contribuir para o incremento do conhecimento sobre a utilização de solos finos para a construção de estruturas de solo reforçado (muros e taludes). Para tal avaliaram-se as diferenças no comportamento mecânico dos materiais compósitos (solo granular reforçado versus solo fino reforçado) e das estruturas de solo reforçado constituídas com os dois tipos de solos. Assim, os objetivos deste estudo foram avaliar: a influência de vários parâmetros nas propriedades mecânicas e na capacidade de carga dos solos reforçados com geossintéticos; a influência de vários parâmetros no dimensionamento das estruturas de solo reforçado; e o comportamento das estruturas dimensionadas (incluindo a estabilidade global e a influência do processo construtivo) recorrendo a uma ferramenta numérica (PLAXIS). Para cumprir os objetivos propostos foram realizadas análises experimentais em laboratório (análise do comportamento do solo reforçado através de ensaios triaxiais e de California Bearing Ratio) e análises numéricas (dimensionamento de estruturas de solo reforçado; modelação numérica do comportamento através de uma ferramenta numérica comercial com o método dos elementos finitos). Os resultados dos ensaios experimentais mostraram que o comportamento mecânico e a capacidade de carga do solo foram incrementados com a inclusão das camadas de geossintético. Este efeito variou com os diversos parâmetros analisados mas, de forma geral, foi mais importante no solo fino (solo com propriedades mecânicas piores). As análises numéricas mostraram que as estruturas de solo fino precisaram de maior densidade de reforços para serem estáveis. Além disso, as estruturas de solo fino foram mais deformáveis e o efeito do seu processo construtivo foi mais importante (principalmente para estruturas de solo fino saturado).

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Despite the importance of coral reefs to humanity, these environments have been threatened throughout the world. Several factors contribute to the degradation of these ecosystems. The Maracajaú Reef Complex, in Rio Grande do Norte state is part of the Coral Reefs Environment Preservation Area in northeastern Brazil. This area has been receiving an increasing influx of tourism and the integrity of the local reefs is a matter of concern. In this study, the reef macroalgae communities were studied and compared within two areas distinguished by the presence or absence of tourism activities. Two sample sites were chosen: the first one, where diving activities are intense; and the other, where these practices do not occur. Samples were collected at both sites within a quadrate of 625 cm2 of area randomly thrown 5 times along a 10 meters transect line. Richness, Shannon-Hill diversity and Simpson dominance indices were determined based on biomass data. Similarity between sites was analyzed with Bray-Curtis similarity and distance index. Fifty-eight macroalgae species were observed, including 7 Chlorophyta, 13 Phaeophyta and 38 Rhodophyta. In the non-disturbed site, 49 species were found, while at the disturbed site, there were 42 species. Dictyotaceae and Corallinaceae were the most representative families at the non-disturbed site, and Rhodomelaceae and Dictyotaceae at the disturbed site. The non-disturbed site presented a higher biomass and the greatest richness and diversity indices. In the disturbed site the dominance index was greater and Caulerpa racemosa was the dominant species. The dendogram based on similarity index showed two major clusters, and an isolated element at the center that corresponds to a sample from the disturbed site. In the first cluster, samples from the non-impacted site were predominant and fleshy brown algae were more conspicuous. The second cluster was composed primarily of samples from the impacted site, where C. racemosa and red filamentous and erect calcareous algae associations (turf forming) were observed covering large extensions. These associations are represented by groups of algae adapted to environments where disturbances are frequent. They can grow rapidly on substrate where benthic community was removed and do not allow the establishment of other species. The results of the present study show that tourism activity is an impacting factor that has been causing shifts in macroalgae communities in the Maracajaú Reef Complex

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A Avaliação do Ciclo de Vida (ACV) considera todo o ciclo de vida do produto, desde a extração e obtenção da matérias-primas, passando pela produção e fabrico de materiais e energia, até ao tratamento de fim de vida e destino final do produto. As Declarações Ambientais de Produto (DAP) são declarações ambientais Tipo III que apresentam um conjunto de informação quantificada e fidedigna, que funciona como uma excelente ferramenta de comunicação relativa ao desempenho ambiental do produto ao longo do seu ciclo de vida. Este relatório de estágio visa, por um lado, analisar os impactes ambientais no decurso do processo de produção do perfil de alumínio sujeito ao tratamento acetinado 20 natural (AC20NA) e, por outro, elaborar um relatório de suporte, que servirá de base para o desenvolvimento da DAP do perfil de alumínio AC20NA a submeter ao sistema DAPHabitat. O relatório foi elaborado tendo por base a norma EN 15804 e inclui as fases obrigatórias (A1-A3). Desta forma, utilizou-se ao software SimaPro para a análise dos impactes ambientais das várias fases do processo de fabrico do perfil de alumínio em estudo. As fases consideradas foram a extrusão, a anodização (tratamento de superfície), a Estação de Tratamento de águas Residuais Industriais (ETARI) e a embalagem. A fase que mais contribui para as diferentes categorias de impacte é a extrusão, uma vez que é nesta fase que é utilizada a matéria-prima para a produção dos perfis de aluminío.

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This thesis describes the theoretical, methodological and programmatic proposal for a multifamily residential building located in the urban expansion area of Parnamirim/RN, inserted in the program Minha Casa Minha Vida and level of energy efficiency "A", as the RegulamentoTécnico de Qualidade (RTQ-R/INMETRO) for residential buildings. The development project initially consists of procedures as the study of theoretical, architectural programming and cases studies. With the delimitation of a field solution, situated between the reference and the context, proposals are studied to determine the solution and architectural detailing of the proposal. The architectural program was built based on the method of Problem Seeking (Peña and Parshall, 2001) and research has highlighted aspects of reducing the environmental impact and of the program Minha Casa Minha Vida , among others. The design process was characterized by the incorporation of aspects reviewed and programmed, seeking them compatible and have an economically viable building, socio-spatial quality and energy efficient. The results show that it is possible to obtain a building that meets the constraints of the program that provides housing and energy efficiency level A - and many other environmental qualities and constructive, particularly through architectural design

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The sharp consumption of natural resources by the construction industry has motivated numerous studies concerning the application of waste to replace partially or fully, some materials, such as aggregates, thereby reducing the environmental impact caused by the extraction of sand and crushing process. The application of stone dust from crushing process arising as an aggregate for the production of Portland cement concrete is a viable alternative in view of the high cost of natural sands, in addition to the environmental damage which causes its operation to the environment. The stone dust has reduced cost compared to natural sand because it is produced in the beds of their own quarries, which are usually located close to major urban centers. This study examined the feasibility of using stone dust from the crushing of rock gneisses in the state of Bahia, replacing natural quartz sand. In the development of scientific study was conducted to characterize physical and chemical raw materials applied and molded cylindrical specimens , using as reference values Fck 20, Fck 25 and Fck 30 MPa ( resistance characteristic of the concrete after 28 days) in following compositions stone powder: 10%, 30%, 50 %, 100% and 100% with additive. The specimens were cured and subjected to the tests of compressive strength and water absorption, then the samples were subjected to the tests of X-ray diffraction and scanning electron microscopy. The results obtained showed that the composition with 10% stone powder showed the best results regarding the physical and mechanical tests performed, confirming the reduction in compressive strength and increased water uptake increased as the content of the powder stone in the concrete composition

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The construction industry is one of the largest consumers of natural raw materials, and concrete is considered today the most used material wide. This accentuated consumption of natural resources has generated concern with the preservation of the environment, and has motivated various studies related to the use of resid ues, which can partially or entirely substitute, with satisfactory performance, some materials such as the aggregate, and in so doing, decrease the impact on the environment caused by the produced residues. Research has been done to better understand and improve the microstructure of concrete, as well as to understand the mechanism of corrosion in reinforced steel. In this context, this work was developed aiming at discovering the influence of the substitution of natural sand by artificial sand, with rega rd to mechanical resistance, microstructure, and durability. To obtain the electrochemical parameters, an adaptation was made to the galvanostatic electrochemical method to study the corrosion in reinforced steel. Concretes of categories 20 MPa and 40 MPa were produced, containing natural sand, and concretes of the same categories were produced with artificial sand substituting the natural sand, and with the addition of sodium nitrate and sodium chloride. Due to the use of rock dust reject (artificial sand), an evaluation was made of its environmental risk. The results indicate that the concretes of category 20 MPa present a better performance than the concrete made with natural sand, thus making it a viable substitute. For the category 40 MPa, the better performance is from the concrete containing natural sand. The adaptation of the galvanostatic electrochemical technique to the study of the corrosion of reinforced steel within concrete proved to be valid for obtaining electrochemical parameters with a high degree of reliability, considering the number of degrees of freedom

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The production of water has become one of the most important wastes in the petroleum industry, specifically in the up stream segment. The treatment of this kind of effluents is complex and normally requires high costs. In this context, the electrochemical treatment emerges as an alternative methodology for treating the wastewaters. It employs electrochemical reactions to increase the capability and efficiency of the traditional chemical treatments for associated produced water. The use of electrochemical reactors can be effective with small changes in traditional treatments, generally not representing a significant additional surface area for new equipments (due to the high cost of square meter on offshore platforms) and also it can use almost the same equipments, in continuous or batch flow, without others high costs investments. Electrochemical treatment causes low environmental impact, because the process uses electrons as reagent and generates small amount of wastes. In this work, it was studied two types of electrochemical reactors: eletroflocculation and eletroflotation, with the aim of removing of Cu2+, Zn2+, phenol and BTEX mixture of produced water. In eletroflocculation, an electrical potential was applied to an aqueous solution containing NaCl. For this, it was used iron electrodes, which promote the dissolution of metal ions, generating Fe2+ and gases which, in appropriate pH, promote also clotting-flocculation reactions, removing Cu2+ and Zn2+. In eletroflotation, a carbon steel cathode and a DSA type anode (Ti/TiO2-RuO2-SnO2) were used in a NaCl solution. It was applied an electrical current, producing strong oxidant agents as Cl2 and HOCl, increasing the degradation rate of BTEX and phenol. Under different flow rates, the Zn2+ was removed by electrodeposition or by ZnOH formation, due the increasing of pH during the reaction. To better understand the electrochemical process, a statistical protocol factor (22) with central point was conducted to analyze the sensitivity of operating parameters on removing Zn2+ by eletroflotation, confirming that the current density affected the process negatively and the flow rate positively. For economical viability of these two electrochemical treatments, the energy consumption was calculated, taking in account the kWh given by ANEEL. The treatment cost obtained were quite attractive in comparison with the current treatments used in Rio Grande do Norte state. In addition, it could still be reduced for the case of using other alternative energy source such as solar, wind or gas generated directly from the Petrochemical Plant or offshore platforms

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Tese (doutorado)—Universidade de Brasília, Instituto de Relações Internacionais, Programa de Pós-Graduação em Relações Internacionais, 2016.

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Despite the importance of coral reefs to humanity, these environments have been threatened throughout the world. Several factors contribute to the degradation of these ecosystems. The Maracajaú Reef Complex, in Rio Grande do Norte state is part of the Coral Reefs Environment Preservation Area in northeastern Brazil. This area has been receiving an increasing influx of tourism and the integrity of the local reefs is a matter of concern. In this study, the reef macroalgae communities were studied and compared within two areas distinguished by the presence or absence of tourism activities. Two sample sites were chosen: the first one, where diving activities are intense; and the other, where these practices do not occur. Samples were collected at both sites within a quadrate of 625 cm2 of area randomly thrown 5 times along a 10 meters transect line. Richness, Shannon-Hill diversity and Simpson dominance indices were determined based on biomass data. Similarity between sites was analyzed with Bray-Curtis similarity and distance index. Fifty-eight macroalgae species were observed, including 7 Chlorophyta, 13 Phaeophyta and 38 Rhodophyta. In the non-disturbed site, 49 species were found, while at the disturbed site, there were 42 species. Dictyotaceae and Corallinaceae were the most representative families at the non-disturbed site, and Rhodomelaceae and Dictyotaceae at the disturbed site. The non-disturbed site presented a higher biomass and the greatest richness and diversity indices. In the disturbed site the dominance index was greater and Caulerpa racemosa was the dominant species. The dendogram based on similarity index showed two major clusters, and an isolated element at the center that corresponds to a sample from the disturbed site. In the first cluster, samples from the non-impacted site were predominant and fleshy brown algae were more conspicuous. The second cluster was composed primarily of samples from the impacted site, where C. racemosa and red filamentous and erect calcareous algae associations (turf forming) were observed covering large extensions. These associations are represented by groups of algae adapted to environments where disturbances are frequent. They can grow rapidly on substrate where benthic community was removed and do not allow the establishment of other species. The results of the present study show that tourism activity is an impacting factor that has been causing shifts in macroalgae communities in the Maracajaú Reef Complex