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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.
61

Design gr?fico da pluma de contamina??o por compostos org?nicos vol?teiss utilizando software CAD na investiga??o de passivo ambiental em um posto revendedor de combust?veis em Natal/RN

Aquino Sobrinho, Hercules Lisboa de 31 January 2011 (has links)
Made available in DSpace on 2014-12-17T14:08:48Z (GMT). No. of bitstreams: 1 HerculesLAS_DISSERT.pdf: 3304337 bytes, checksum: 041717a4cfd116130802eab3678923c7 (MD5) Previous issue date: 2011-01-31 / Among the potentially polluting economic activities that compromise the quality of groundwater are the gas stations. The city of Natal has about 120 gas stations, of which only has an environmental license for operation. Discontinuities in the offices were notified by the Public Ministry of Rio Grande do Norte to carry out the environmental adaptations, among which is the investigation of environmental liabilities. The preliminary and confirmatory stages of this investigation consisted in the evaluation of soil gas surveys with two confirmatory chemical analysis of BTEX, PAH and TPH. To get a good evaluation and interpretation of results obtained in the field, it became necessary three-dimensional representation of them. We used a CAD software to graph the equipment installed in a retail service station fuel in Natal, as well as the plumes of contamination by volatile organic compounds. The tool was concluded that contamination is not located in the current system of underground storage of fuel development, but reflects the historical past in which tanks were removed not tight gasoline and diesel / Dentre as atividades econ?micas potencialmente poluidoras que comprometem a qualidade das ?guas subterr?neas est?o os Postos Revendedores de Combust?veis. A cidade do Natal possui cerca de 120 postos de combust?veis, dos quais, apenas um possui licen?a ambiental de opera??o. Os postos em desconformidade foram notificados pelo Minist?rio P?blico do Rio Grande do Norte para realizarem as adequa??es ambientais, dentre as quais est? a investiga??o de passivo ambiental. As fases preliminar e confirmat?ria desta investiga??o consistiram na avalia??o de gases do solo com duas sondagens confirmat?rias para an?lises qu?micas de BTEX, HPA e TPH. Para obter-se uma boa avalia??o e interpreta??o dos resultados obtidos no campo, se fez necess?rio a representa??o tridimensional dos mesmos. Utilizou-se um software CAD para representar graficamente os equipamentos instalados em um posto revendedor de combust?vel em Natal/RN, assim como as plumas de contamina??o por compostos org?nicos vol?teis. A partir desta ferramenta foi poss?vel concluir que a contamina??o n?o est? localizada no atual Sistema de Armazenamento Subterr?neo de Combust?vel do empreendimento, mas reflete o hist?rico passado em que foram removidos tanques n?o estanques de gasolina e diesel
62

Avalia??o da correla??o entre os par?metros, carbono org?nico total e elementos t?xicos, em solo de um posto de servi?o e revenda de combust?veis / Avalia??o da correla??o entre os par?metros, carbono org?nico total e elementos t?xicos, em solo de um posto de servi?o e revenda de combust?veis

Coelho, Eduardo Philipp Medeiros 31 January 2011 (has links)
Made available in DSpace on 2014-12-17T14:08:52Z (GMT). No. of bitstreams: 1 EduardoPMC_DISSERT.pdf: 2258770 bytes, checksum: b0f9f75ce68f7e376f8b9edab280c699 (MD5) Previous issue date: 2011-01-31 / Today a major responsibility for the contamination of soil and groundwater and surface water are establishments known as gas stations of fuel which has attracted increasing attention from both the general population as the state agencies of environmental control due to leaks in storage tanks and mainly to disruption of pipe corrosion of tanks and pumping. Other services, like oil changes and car wash are also causes for concern in this type of establishment. These leaks can cause or waste produced, and the contamination of aquifers, serious health problems and public safety, since most of these stations located in urban areas. Based on this, the work was to evaluate soil contamination of a particular service station and fuel sales in the city of Natal, through the quantification of heavy metals like Cd, Cu, Cr, Ni, Pb, Zn of total organic carbon (TOC) and organic matter using different techniques such as optical emission spectrometry with inductively coupled plasma source (ICP OES), Total Organic Carbon analyzer and gravimetric analysis respectively. And also to characterize the soil through particle size analysis. Samples were taken in 21 georeferenced points and collected in the same period. The soils sampled in sampling stations P3, P5, P6, P10, P11, P12, P13, P14, P15, P17, P18 and P20 showed the smallest size fractions ranging from fine sand to medium sand. The other study sites ranged from fine sand to medium sand, except the point P8 showed that only the type size medium sand and P19, indicating a particle size of the coarse type. The small correlation of organic matter with the elements studied in this work suggests that these are not of anthropogenic origin but geochemical support / Hoje um dos grandes respons?veis pela contamina??o do solo e ?guas subterr?neas e superficiais s?o os estabelecimentos conhecidos como postos de revenda de combust?veis que vem merecendo cada vez mais aten??o tanto da popula??o em geral como dos ?rg?os estaduais de controle ambiental devido a vazamentos em tanques de armazenamento, e principalmente ao rompimento da tubula??o de bombeamento e corros?o dos tanques. Outros servi?os como, troca de ?leo e lavagem de autom?veis tamb?m s?o motivos de preocupa??o neste tipo de estabelecimento. Estes vazamentos ou residuais produzidos podem causar, al?m da contamina??o de aq??feros, graves problemas de sa?de e de seguran?a p?blica, visto que a maioria destes postos localiza-se em ?reas urbanas. Baseado nisto, o trabalho realizado teve como objetivo avaliar a contamina??o do solo de um determinado posto de servi?os e revenda de combust?veis na Cidade de Natal, RN, por meio da quantifica??o de metais pesados como Cd, Cu, Cr, Ni, Pb, Zn, do teor de carbono org?nico total (COT) e da mat?ria org?nica utilizando t?cnicas distintas como espectrometria de emiss?o ?ptica com fonte de plasma indutivamente acoplado (ICP OES), analisador de Carbono Org?nico Total e an?lise gravim?trica respectivamente. E ainda caracterizar o solo por meio de an?lise granulom?trica. As amostragens foram realizadas em 21 pontos georeferenciados e coletadas no mesmo per?odo. Os solos amostrados nas esta??es de coleta P3, P5, P6, P10, P11, P12, P13, P14, P15, P17, P18 e P20 apresentaram as menores fra??es granulom?tricas variando de areia muito fina a areia m?dia. As demais esta??es de coleta variaram de areia fina a areia m?dia, exceto o ponto P8 que apresentou somente granulometria do tipo areia m?dia e P19, indicando granulometria do tipo grossa. A pequena correla??o da mat?ria org?nica com os elementos estudados neste trabalho sugere que estes n?o sejam de origem antr?pica e sim de suporte geoqu?mico
63

Investiga??o e gerenciamento de ?reas contaminadas por postos revendedores de combust?veis em Natal

Ramalho, Adriana Margarida Zanbotto 06 May 2013 (has links)
Made available in DSpace on 2014-12-17T14:09:17Z (GMT). No. of bitstreams: 1 AdrianaMSR_TESE.pdf: 15407461 bytes, checksum: 9724571238317c177c2fdb4b02772cad (MD5) Previous issue date: 2013-05-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Activities that have fuel subterranean storage system are considered potentially polluting fuels by CONAMA Resolution 273, due to the possibility of leak, outpouring and overflow of fuel into the ground. Being even more worrying when contaminate groundwater for public supply, as the case of Natal City. For this reason, the Public Ministry/RN, in partnership with UFRN, developed the project environmental suitability of Gas stations in Natal, of which 36% showed evidence of contamination. This paper describes the four stages of the management of contaminated areas: preliminary assessment of environmental liabilities, detailed confirmatory investigation of the contamination, risk analysis to human health (RBCA), as well as the remediation plan of degraded areas. Therefore it is presented a case study. For the area investigated has been proposed a mathematical method to estimate the volume of LNAPL by a free CAD software (ScketchUp) and compare it with the partition method for grid area. Were also performed 3D graphics designs of feathers contamination. Research results showed that passive benzene contamination in groundwater was 2791.77 ?g/L, when the maximum allowed by CONAMA Resolution 420 is 5 ?g/L which is the potability standards. The individual and cumulative risks were calculated from 4.4 x10-3, both above the limits of 1.0 x10-5 or by RBCA 1.0 x10-6 by the Public Ministry/RN. Corrective action points that remediation of dissolved phase benzene is expected to reach a concentration of 25 ?g/L, based on carcinogenic risk for ingestion of groundwater by residents residential, diverging legislation. According to the proposed model, the volume of LNAPL using the ScketchUp was 17.59 m3, while by the grid partitioning method was 14.02 m3. Because of the low recovery, the expected removal of LNAPL is 11 years, if the multiphase extraction system installed in the enterprise is not optimized / Atividades que possuem sistema de armazenamento subterr?neo de combust?veis s?o consideradas potencialmente poluidoras pela Resolu??o CONAMA 273/2000, devido ? possibilidade de vazamento, derramamento e transbordamento de combust?veis para o solo. Sendo ainda mais preocupante quando contaminam ?guas subterr?neas destinadas ao abastecimento p?blico, como o caso de Natal. Por este motivo, o Minist?rio P?blico/RN, em parceria com a UFRN, desenvolveu o projeto de adequa??o ambiental dos postos revendedores de combust?veis em Natal, dos quais 36% apresentaram ind?cios de contamina??o. Este trabalho descreve as quatro etapas do gerenciamento de ?reas contaminadas: avalia??o preliminar do passivo ambiental, investiga??o confirmat?ria detalhada da contamina??o, an?lise de risco a sa?de humana (RBCA), bem como o plano de remedia??o das ?reas degradadas. E apresenta um estudo de caso. Para a ?rea investigada ? proposto um m?todo matem?tico para estimar o volume de fase livre auxiliado por um software CAD livre (ScketchUp), este foi comparado com o m?todo de parti??o da ?rea por grid. Tamb?m s?o realizados os designs gr?ficos 3D das plumas de contamina??o. Os resultados da investiga??o de passivo mostraram que a contamina??o por benzeno na ?gua subterr?nea foi 2791,77 ?g/L, quando o m?ximo permitido pela Resolu??o CONAMA 420/2009 ? de 5 ?g/L que ? o padr?o de potabilidade. Os riscos individual e cumulativo calculados foram de 4,4x10-3, ambos acima dos limites aceit?veis pelo RBCA de 1,0x10-5 ou pelo Minist?rio P?blico/RN de 1,0x10-6. A a??o corretiva aponta que a remedia??o da fase dissolvida de benzeno dever? atingir uma concentra??o de 25 ?g/L, com base no risco carcinog?nico, para ingest?o de ?gua subterr?nea para moradores residenciais, divergindo da legisla??o. De acordo com o modelo proposto, o volume de fase livre utilizando o ScketchUp foi de ? de 17,59 m3, enquanto o m?todo de parti??o por grid foi de 14,02 m3. Devido ? baixa recupera??o, a previs?o de remo??o da fase livre ? de 11 anos, caso o sistema de extra??o multif?sica instalado no empreendimento n?o seja otimizado / 2020-01-01
64

Uma metodologia para a an?lise do desempenho sustent?vel dos postos de revenda de combust?vel na cidade de Natal/RN, com o uso de data envelopment analysis-DEA

Francisco, Cl?udia Aparecida Cavalheiro 24 May 2013 (has links)
Made available in DSpace on 2014-12-17T14:09:18Z (GMT). No. of bitstreams: 1 ClaudiaACF_TESE.pdf: 6242500 bytes, checksum: 7a857ce8be46bd85b252fca3bf3fa45c (MD5) Previous issue date: 2013-05-24 / The increasing use of fossil fuels in line with cities demographic explosion carries out to huge environmental impact in society. For mitigate these social impacts, regulatory requirements have positively influenced the environmental consciousness of society, as well as, the strategic behavior of businesses. Along with this environmental awareness, the regulatory organs have conquered and formulated new laws to control potentially polluting activities, mostly in the gas stations sector. Seeking for increasing market competitiveness, this sector needs to quickly respond to internal and external pressures, adapting to the new standards required in a strategic way to get the Green Badge . Gas stations have incorporated new strategies to attract and retain new customers whom present increasingly social demand. In the social dimension, these projects help the local economy by generating jobs and income distribution. In this survey, the present research aims to align the social, economic and environmental dimensions to set the sustainable performance indicators at Gas Stations sector in the city of Natal/RN. The Sustainable Balanced Scorecard (SBSC) framework was create with a set of indicators for mapping the production process of gas stations. This mapping aimed at identifying operational inefficiencies through multidimensional indicators. To carry out this research, was developed a system for evaluating the sustainability performance with application of Data Envelopment Analysis (DEA) through a quantitative method approach to detect system s efficiency level. In order to understand the systemic complexity, sub organizational processes were analyzed by the technique Network Data Envelopment Analysis (NDEA) figuring their micro activities to identify and diagnose the real causes of overall inefficiency. The sample size comprised 33 Gas stations and the conceptual model included 15 indicators distributed in the three dimensions of sustainability: social, environmental and economic. These three dimensions were measured by means of classical models DEA-CCR input oriented. To unify performance score of individual dimensions, was designed a unique grouping index based upon two means: arithmetic and weighted. After this, another analysis was performed to measure the four perspectives of SBSC: learning and growth, internal processes, customers, and financial, unifying, by averaging the performance scores. NDEA results showed that no company was assessed with excellence in sustainability performance. Some NDEA higher efficiency Gas Stations proved to be inefficient under certain perspectives of SBSC. In the sequence, a comparative sustainable performance and assessment analyzes among the gas station was done, enabling entrepreneurs evaluate their performance in the market competitors. Diagnoses were also obtained to support the decision making of entrepreneurs in improving the management of organizational resources and promote guidelines the regulators. Finally, the average index of sustainable performance was 69.42%, representing the efforts of the environmental suitability of the Gas station. This results point out a significant awareness of this segment, but it still needs further action to enhance sustainability in the long term / A crescente utiliza??o de combust?veis f?sseis alinhada ? explos?o demogr?fica em centros urbanos tem ocasionado grandes problemas de impacto ambiental na sociedade. Para mitigar esses impactos, as exig?ncias dos ?rg?os reguladores t?m influenciado positivamente na consci?ncia ambiental da sociedade, bem como no comportamento estrat?gico das empresas. Com essa consci?ncia ambiental, os ?rg?os t?m conquistado maiores respaldos e formulado novas legisla??es no controle de atividades potencialmente poluidoras, sobretudo no setor dos postos revendedores de combust?veis. Em busca de aumentar a competitividade no mercado, esse segmento precisa responder rapidamente ?s press?es (externas e internas), adequando-se aos novos padr?es exigidos de maneira estrat?gica na obten??o do selo verde. Os postos t?m incorporado novas estrat?gias para atrair e fidelizar clientes cada vez mais exigentes. No ?mbito social, esses empreendimentos auxiliam a economia local com a gera??o de empregos e distribui??o de renda. Mediante esse contexto, o presente trabalho tem como objetivo alinhar as dimens?es social, econ?mica e ambiental caracterizando a mensura??o do desempenho sustent?vel nos postos de revenda de combust?vel na cidade do Natal/RN. As perspectivas do Balanced Scorecard Sustent?vel (SBSC) foram fundamentadas por meio de um conjunto de indicadores para mapear o processo produtivo dos postos. Esse mapeamento visou identificar a inefici?ncia operacional por meio de indicadores multidimensionais. Na condu??o desta pesquisa, elaborou-se um sistema de avalia??o do desempenho sustent?vel com aplica??o do Data Envelopment Analysis (DEA), uma abordagem quantitativa para detectar o n?vel de efici?ncia do sistema. Com o intuito de compreender a complexidade sist?mica, os sub processos organizacionais foram analisados por meio da t?cnica Network Data Envelopment Analysis (NDEA) com o desmembramento das suas micro atividades para identificar e diagnosticar as reais causas de inefici?ncia. O tamanho amostral foi composto por 33 postos de revenda de combust?vel e o modelo conceitual contemplou 15 indicadores distribu?dos nas tr?s dimens?es da sustentabilidade: social, ambiental e econ?mica. Essas tr?s dimens?es foram mensuradas por meio de modelos cl?ssicos DEA-CCR com orienta??o input. Visando unificar o escore de desempenho individual das dimens?es, foi elaborado um ?nico ?ndice considerado parcialmente agrupado por meio de duas m?dias: aritm?tica e ponderada. Posteriormente, outra an?lise foi realizada para mensurar as quatro perspectivas do SBSC: aprendizado e crescimento; processos internos; clientes; e, financeira, unificando, por meio da m?dia os escores de desempenho. Os resultados do modelo NDEA apontaram que nenhuma empresa foi avaliada com excel?ncia no desempenho sustent?vel. Os postos com maiores ?ndices de efici?ncia mostraram-se ineficientes em determinadas perspectivas do SBSC. Na sequ?ncia, as an?lises apresentaram uma avalia??o do desempenho sustent?vel e das perspectivas de maneira comparativa entre os postos, possibilitando aos empres?rios avaliarem seu desempenho entre os concorrentes. Foram tamb?m obtidos diagn?sticos para subsidiar a tomada de decis?o dos empres?rios na melhoria do gerenciamento dos recursos organizacionais e promover diretrizes balizadoras nos ?rg?os regulamentadores. O escore m?dio do desempenho sustent?vel foi 69,42% representando os esfor?os empreendidos na adequa??o ambiental dos postos. Isso sinaliza uma consider?vel consci?ncia desse segmento, por?m ainda necessita de novas a??es para incrementar a sustentabilidade no longo prazo
65

Licenciamento ambiental em postos de revenda de combust?veis ? luz dos princ?pios constitucionais de defesas do meio ambiente: o caso do munic?pio de Natal/RN

Silva, Carlos S?rgio Gurgel da 06 September 2010 (has links)
Made available in DSpace on 2014-12-17T14:27:14Z (GMT). No. of bitstreams: 1 CarlosSGS_DISSERT.pdf: 1178601 bytes, checksum: a28efb1abc1d8f161f4f10625c193e6c (MD5) Previous issue date: 2010-09-06 / This study approaches the question of the administrative procedure of the environmental licensing of ranks of fuel resale, taking as basis a study case of the reality of the City of Natal/RN (Brazil). For in such a way, it was done a retrospect on the evolution of the system of road transport in Brazil, having started to briefly analyze the urbanization process that if after accented in the capitals of the Brazilian States the decade of 1950, relating these subjects with the growth of the sector of fuel resale. After that, it was transferred boarding of the defense of the national environment to the light of ambient principles constitutional. In the sequence, a boarding on the ambient guardianship in the Federal Constitution of 1988 was made, treating basically specifies and on the national urban politics and the national politics of the environment, with its instruments. In the sequence, it was transferred the analysis of the abilities and attributions of the National Advice of the Environment (CONAMA) and its Resolutions, for then only enter in the most important part of this work: an analysis of the environmental licensing of ranks of fuel resale, in the reality of the City of Natal/RN. Before this specific boarding, it was proceeded specifically a survey and communication from the applicable norms to such establishments (Resolutions of the CONAMA and norms of the ABNT), for after that carrying through an geo-ambient characterization of the City of Natal/RN. Finally, a reflection was made on the possibility of magnifying of the state activity, in terms of guarantees for the responsible members for the environmental policy and of administrative efficiency, through the idea of the ambient regulation. For the accomplishment of this study, it was proceeded research in diverse sources such as books, magazines, sites of the Internet, periodicals, thesis and dissertations, among others material, beyond visits the agencies that direct or indirectly act with the ambient defense and as fuel resale, such as Secretariat of Environment and Urbanism of the City of Natal (SEMURB), Institute of Economic Development and Environment of RN (IDEMA), Brazilian Institute of the Environment and the Natural resources You renewed, Executive Management of RN (IBAMA/RN), Public prosecutor's office of the Environment of Natal (Public prosecution service of the RN), National Agency of Oil (ANP) and Union of the Retailing of Derivatives of Oil of the RN, among others. To the end, satiated regulation is observed that although on the substance of the ambient licensing in ranks of fuel resale, also with federal, state and municipal norms, the municipal Public Power is very far from the fulfilment of its institutional functions, in the question environmental policy of these establishments, a time that few are the permitted ranks of resale in the city of Natal/RN / Esta disserta??o aborda a quest?o do procedimento administrativo do licenciamento ambiental de postos de revenda de combust?veis, tomando-se como base um estudo de caso da realidade do Munic?pio de Natal/RN. Para tanto, partiu-se de um retrospecto sobre a evolu??o do sistema de transporte rodovi?rio no Brasil, passando a analisar brevemente o processo de urbaniza??o que se acentuou nas capitais dos Estados brasileiros ap?s a d?cada de 1950, relacionando estes temas com o crescimento do setor de revenda de combust?veis. Em seguida, passou-se a abordagem da defesa do meio ambiente nacional ? luz de princ?pios constitucionais ambientais. Na seq??ncia, foi feita uma abordagem sobre a tutela ambiental na Constitui??o Federal de 1988, tratando especifica e basicamente sobre a pol?tica urbana nacional e a pol?tica nacional do meio ambiente, com seus instrumentos. Na seq??ncia, passou-se ? an?lise das compet?ncias e atribui??es do Conselho Nacional do Meio Ambiente (CONAMA) e de suas Resolu??es, para s? ent?o adentrar na parte mais importante do trabalho: uma an?lise do licenciamento ambiental de postos de revenda de combust?veis, na realidade do Munic?pio de Natal/RN. Antes desta abordagem espec?fica, procedeu-se a um levantamento e explana??o das normas aplic?veis especificamente a tais estabelecimentos (Resolu??es do CONAMA e normas da ABNT), para em seguida realizar uma caracteriza??o geo-ambiental do Munic?pio de Natal/RN. Por fim, realizouse uma reflex?o sobre a possibilidade de amplia??o da atividade estatal, em termos de garantias para os membros respons?veis pela fiscaliza??o ambiental e de efici?ncia administrativa, atrav?s da id?ia da regula??o ambiental. Para a realiza??o deste estudo, procedeu-se a pesquisas em diversas fontes tais como livros, revistas, s?tios da internet, jornais, teses e disserta??es, entre outros materiais, al?m de visitas a ?rg?os que direta ou indiretamente atuam com a defesa ambiental e como revenda de combust?veis, tais como Secretaria de Meio Ambiente e Urbanismo do Munic?pio de Natal (SEMURB), Instituto de Desenvolvimento Econ?mico e Meio Ambiente do RN (IDEMA), Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renov?veis, Ger?ncia Executiva do RN (IBAMA/RN), Promotoria do Meio Ambiente de Natal (Minist?rio P?blico do RN), Ag?ncia Nacional do Petr?leo (ANP) e Sindicato do Com?rcio Varejista de Derivados de Petr?leo do RN, entre outros. Ao final, observa-se que apesar de farta regulamenta??o sobre a mat?ria do licenciamento ambiental em postos de revenda de combust?veis, inclusive com normas federais, estaduais e municipais, o Poder P?blico municipal est? muito aqu?m do cumprimento de suas fun??es institucionais, no quesito fiscaliza??o ambiental destes estabelecimentos, uma vez que poucos s?o os postos de revenda licenciados na cidade de Natal/RN
66

An?lise de antenas utilizando substrato cer?mico, zpt, produzido por s?ntese auto propagante para aplica??es em sistemas de micro-ondas

Martins, Jo?mia Leilane Gomes de Medeiros 07 June 2013 (has links)
Made available in DSpace on 2014-12-17T14:55:13Z (GMT). No. of bitstreams: 1 JoemiaLGMM_TESE.pdf: 3140610 bytes, checksum: 8bdf88d29c888d95e74fd24e403e60fc (MD5) Previous issue date: 2013-06-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Ceramic substrates have been investigated by researchers around the world and has achieved a high interest in the scientific community, because they had high dielectric constants and excellent performance in the structures employed. Such ceramics result in miniaturized structures with dimensions well reduced and high radiation efficiency. In this work, we have used a new ceramic material called lead zinc titanate in the form of Zn0,8Pb0,2TiO3, capable of being used as a dielectric substrate in the construction of various structures of antennas. The method used in constructing the ceramic combustion synthesis was Self- Sustained High Temperature (SHS - "Self-Propagating High-Temperature Synthesis") which is defined as a process that uses highly exothermic reactions to produce various materials. Once initiated the reaction area in the reaction mixture, the heat generated is sufficient to become self-sustaining combustion in the form of a wave that propagates converting the reaction mixture into the product of interest. Were analyzed aspects of the formation of the composite Zn0,8Pb0,2TiO3 by SHS powders and characterized. The analysis consisted of determining the parameters of the reaction for the formation of the composite, as the ignition temperature and reaction mechanisms. The production of composite Zn0,8Pb0,2TiO3 by SHS performed in the laboratory, was the result of a total control of combustion temperature and after obtaining the powder began the development of ceramics. The product was obtained in the form of regular, alternating layers of porous ceramics and was obtained by uniaxial pressing. 10 The product was characterized by analysis of dilatometry, X-ray diffraction analysis and scanning electron microscopy. One of the contributions typically defined in this work is the development of a new dielectric material, nevertheless presented previously in the literature. Therefore, the structures of the antennas presented in this work consisted of new dielectric ceramics based Zn0,8Pb0,2TiO3 usually used as dielectric substrate. The materials produced were characterized in the microwave range. These are dielectrics with high relative permittivity and low loss tangent. The Ansoft HFSS, commercial program employee, using the finite element method, and was used for analysis of antennas studied in this work / Substratos cer?micos t?m sido investigados por pesquisadores de todo o mundo e tem despertado um grande interesse na comunidade cient?fica, pelo fato de apresentarem altas constantes diel?tricas e um excelente desempenho nas estruturas empregadas. Tais cer?micas resultam em estruturas miniaturizadas, com dimens?es bem reduzidas e de alta efici?ncia de radia??o. Neste trabalho, utilizou-se um novo material cer?mico, chamado de titanato de zinco chumbo, na forma de Zn0,8Pb0,2TiO3, capaz de ser utilizado como substrato diel?trico na constru??o de diversas estruturas de antenas. O m?todo utilizado na constru??o da cer?mica foi a S?ntese por Combust?o Auto-Sustentada a Alta Temperatura (SHS Self-Propagating High-Temperature Synthesis ) que ? definido como um processo que utiliza rea??es altamente exot?rmicas para produzir os mais diversos materiais. Uma vez iniciada a rea??o numa ?rea da mistura reagente, o calor gerado ? suficiente para tornar a combust?o auto-sustent?vel, na forma de uma onda que se propaga convertendo a mistura reagente no produto de interesse. Foram analisados os aspectos da forma??o do comp?sito Zn0,8Pb0,2TiO3 por SHS e os p?s obtidos, foram caracterizados. A an?lise consistiu na determina??o dos par?metros da rea??o para a forma??o do comp?sito, como a temperatura de igni??o e os mecanismos de rea??o. A produ??o do comp?sito Zn0,8Pb0,2TiO3 por SHS, realizada em laborat?rio, foi resultado de um controle total da temperatura de combust?o e ap?s a obten??o do p? 8 iniciou-se o desenvolvimento das cer?micas. O produto foi obtido na forma de camadas regulares e altern?ncia de porosidades e as cer?micas foram obtidas por prensagem uniaxial. O produto foi caracterizado atrav?s de an?lises de dilatometria, difra??o de raios-X e an?lise de microscopia de varredura eletr?nica. Uma das contribui??es principais deste trabalho foi o desenvolvimento de um novo material diel?trico, n?o obstante apresentado anteriormente na literatura. Portanto, as estruturas das antenas apresentadas neste trabalho foram constitu?das por novas cer?micas diel?tricas ? base de Zn0,8Pb0,2TiO3, geralmente utilizado como substrato diel?trico. Os materiais desenvolvidos foram caracterizados na faixa de micro-ondas. S?o substratos diel?tricos de alta permissividade relativa e baixa tangente de perda. O software comercial empregado, Ansoft HFSS, baseado no m?todo dos elementos finitos, foi utilizado na an?lise das antenas estudadas neste trabalho
67

An?lise das emiss?es atmosf?ricas por ve?culos automotores em Natal-RN

Brito, Herm?nio Pereira de 11 November 2005 (has links)
Made available in DSpace on 2014-12-17T14:58:11Z (GMT). No. of bitstreams: 1 HerminioPB.pdf: 3768069 bytes, checksum: 694372597a20b234c0403ab08b7bc801 (MD5) Previous issue date: 2005-11-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The fast urban occupation of Brazil, mainly from the last decade of 50, a sensible degradation of the quality of the air generated mainly for the activities was verified human beings associates to industrialization. From the past years, the situation has gotten worst in function of the increment of the fleet of vehicles in circulation in the great cities. Being these, in the city of Natal-RN, the ones that offer the biggest contributions to the atmospheric pollution. For atmospheric air to be a finite natural resources, indispensable and essential to the maintenance of the life in the land, is necessary to the implementation of action to improve its quality and to protect the health of the population. With the objective to study relative aspects to the characteristics of vehicles in use, the present study it searchs to analyze the levels of emissions of gases generated for vehicles converted bi-fuels into the modalities: natural gas (GNV), gasoline and alcohol, inspected for ends of register and together licensing to the State Department of Transit. One used the data gotten from inspections carried through for the company System Specialized in Inspection To propagate, in the city of the Natal-RN, capital of the State of Rio Grande do Norte, between 14 of November of 2003 and 30 of December of 2004. The analyzed parameters are established in the resolution n? 07/93 CONAMA. Of a total of 1.517 inspected vehicles, a average of 15,2% of failed was gotten, or either, that they emit levels of pollution above of the limits established for the legislation, below of the national average that is of 20,0%. The analysis of the data discloses that 7.3% of the fleet are converted the GNV; the growth of vehicles converted the GNV into the city is gradual, with a average of increment in last the 4 years of 23,3%; it has a vehicle predominance that has as combustible original to the gasoline (88,2%); the inspected fleet has average age of 8 years of use, considered young for the Brazilian standards, except for the moved one to the alcohol (average of use of 15 years). Moreover, the type of fuel is not the main parameter to define the indices of emissions; the age of the fleet is the parameter most important when emission is analyzed to propagate; the gas that more generates failed in the inspections is the corrected carbon monoxide; the vehicles generate higher indices of emissions in idling for all the fuels; the presence of the catalyser was not reflected, as it expected, in the reduction of emissions of gases toxic, however when analyzed according to year of manufacture, it was observed that for the vehicles manufactured between 1997 and 2004, reduction of 46,0% in the failed of the vehicles equipped with catalyser was gotten. In conclusion, the fleet of the studied sample, in average terms, takes care of to the requirements of Resolution CONAMA n? 07/93. The results gotten for the present study can subsidize action of public administrations that aim at to the improvement and the maintenance of the quality of air in the city of Natal-RN, as, for example, to implant a net of monitoramento of the quality of air / Com a r?pida ocupa??o urbana do Brasil, notadamente a partir da ?ltima d?cada de 50, verificou-se uma sens?vel degrada??o da qualidade do ar gerada principalmente pelas atividades humanas associadas ? industrializa??o. Ao longo dos anos, esta situa??o tem se agravado em fun??o do incremento da frota de ve?culos automotores em circula??o nas grandes cidades. Sendo estes, na cidade de Natal-RN, os que oferecem as maiores contribui??es ? polui??o atmosf?rica. Pelo ar atmosf?rico ser um recurso natural finito, indispens?vel e essencial ? manuten??o da vida na terra, ? necess?ria ? implementa??o de a??es para melhorar sua qualidade e proteger a sa?de da popula??o. Com o objetivo de estudar aspectos relativos as caracter?sticas de ve?culos automotores em uso, o presente estudo busca analisar os n?veis de emiss?es de gases gerados por ve?culos automotores convertidos a bi-combust?veis nas modalidades: G?s Natural Veicular, Gasolina e ?lcool, inspecionados para fins de registro e licenciamento junto ao Departamento Estadual de Tr?nsito do Rio Grande do Norte. Utilizaram-se os dados obtidos a partir de inspe??es realizadas pela empresa Sistema Especializado em Inspe??o Veicular, na cidade do Natal, capital do Rio Grande do Norte, entre os dias 14 de novembro de 2003 e 30 de dezembro de 2004. Os par?metros analisados foram os estabelecidos na resolu??o n? 07/93 CONAMA. De um total de 1.517 ve?culos inspecionados, obteve-se uma m?dia de 15,2% de reprova??o, ou seja, que emitem n?veis de polui??o acima dos limites estabelecidos pela legisla??o, abaixo da m?dia nacional que ? de 20,0%. A an?lise dos dados revela que 7,3% da frota ? convertida a GNV; o crescimento da frota de ve?culos convertidos a GNV na cidade, ? progressivo, com uma m?dia de incremento nos ?ltimos 4 anos de 23,3%; h? um predom?nio de ve?culos que t?m como combust?vel original a gasolina (88,2%); a frota inspecionada tem idade m?dia de 8 anos de uso, considerada jovem para os padr?es brasileiros, exceto para a movida ? ?lcool (m?dia de uso 15 anos). Al?m disso, tipo de combust?vel n?o ? o principal par?metro para se definir os ?ndices de emiss?es; a idade da frota ? o par?metro mais importante quando se analisa emiss?o veicular; o g?s que mais gera reprova??o nas inspe??es ? o mon?xido de carbono corrigido; os ve?culos geram ?ndices mais elevados de emiss?es em marcha lenta para todos os combust?veis; a presen?a do catalisador n?o se refletiu, como se esperava, na redu??o de emiss?es de gases t?xicos, por?m quando analisado segundo o ano de fabrica??o, observou-se que para os ve?culos fabricados entre 1997 e 2004, houve uma redu??o de 46,0% nas reprova??es dos ve?culos equipados com catalisador. Em conclus?o, a frota estudada em m?dia atende as exig?ncias da Resolu??o CONAMA n? 07/93. Os resultados apresentados no presente estudo podem subsidiar a??es de gest?es p?blicas que visem ? melhoria e a manuten??o da qualidade do ar na cidade de Natal, como, por exemplo, implantar uma rede de monitoramento da qualidade do ar
68

Degrada??o catal?tica de polietileno de alta densidade sobre a ze?lita HZSM

Lima, Stevie Hallen 31 August 2009 (has links)
Made available in DSpace on 2014-12-17T15:41:46Z (GMT). No. of bitstreams: 1 StevieHLpdf.pdf: 1475886 bytes, checksum: e83c49569bddebb612701e2de7e607bc (MD5) Previous issue date: 2009-08-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In last years it has talked a lot about the environment and the plastic waste produced and discarded. In last decades, the increasing development of research to obtain fuel from plastic material, by catalytic degradation, it has become a very attractive looking, as these tailings are discarded to millions worldwide. These materials take a long time to degrade themselves by ways said natural and burning it has not demonstrated a viable alternative due to the toxic products produced during combustion. Such products could bring serious consequences to public health and environment. Therefore, the technique of chemical recycling is presented as a suitable alternative, especially since could be obtain fractions of liquid fuels that can be intended to the petrochemical industry. This work aims to propose alternatives to the use of plastic waste in the production of light petrochemical. Zeolites has been widely used in the study of this process due to its peculiar structural properties and its high acidity. In this work was studied the reaction of catalytic degradation of high-density polyethylene (HDPE) in the presence HZSM-12 zeolites with different acid sites concentrations by thermogravimetry and pyrolysis coupled with GC-MS. The samples of the catalysts were mixed with HDPE in the proportion of 50% in mass and submitted to thermogravimetric analyses in several heating rates. The addition of solids with different acid sites concentrations to HDPE, produced a decrease in the temperature of degradation of the polymer proportional the acidity of the catalyst. These qualitative results were complemented by the data of activation energy obtained through the non-isothermal kinetics model proposed by Vyazovkin. The values of Ea when correlated to the data of surface acidity of the catalysts indicated that there is a exponential decrease of the energy of activation in the reaction of catalytic degradation of HDPE, in function of the concentration of acid sites of the materials. These results indicate that the acidity of the catalyst added to the system is one of the most important properties in the reaction of catalytic degradation of polyethylene / Nos ?ltimos anos tem-se falado muito sobre o meio ambiente e sobre o lixo pl?stico produzido e descartado. Nas ?ltimas d?cadas, o crescente desenvolvimento de pesquisas com o intuito de obter combust?veis a partir de material pl?stico, via degrada??o catal?tica, tem-se tornado uma busca muito atrativa, j? que esses rejeitos s?o descartados aos milh?es em todo mundo. Esses materiais levam muito tempo para se degradar por meios ditos naturais e sua incinera??o n?o tem se demonstrado uma alternativa vi?vel devido aos produtos t?xicos produzidos durante sua combust?o. Tais produtos conseq?entes poderiam trazer s?rios problemas de sa?de p?blica e ambiental. Logo, a t?cnica da reciclagem qu?mica apresenta-se como uma alternativa adequada, inclusive porque podemos obter fra??es leves do petr?leo que podem ser destinadas ao setor petroqu?mico. Este trabalho tem como objetivo propor alternativas para o aproveitamento de lixo pl?stico na produ??o de combust?veis l?quidos. Ze?litas tem sido amplamente utilizada no estudo desse processo devido ?s suas propriedades estruturais peculiares e sua alta acidez. Neste trabalho, investigou-se a rea??o de degrada??o de Polietileno de Alta Densidade (PEAD) na presen?a de HZSM-12, com diferentes concentra??es de s?tios ?cidos, atrav?s da termogravimetria e pir?lise acoplada ? cromatografia ? g?s e ao espectr?metro de massa (Py-GC-MS). As amostras de catalisadores foram misturadas com PEAD na propor??o de 50% em massa e submetidas a an?lises em diferentes taxas de aquecimento. A adi??o de catalisadores com diferentes concentra??es de s?tios ?cidos produziu uma diminui??o na temperatura de degrada??o do pol?mero proporcional ? acidez do catalisador. Estes resultados qualitativos foram complementados por dados da energia de ativa??o (Ea) obtidos atrav?s do modelo cin?tico n?o-isot?rmico proposto por Vyazovkin. Os valores das Ea quando correlacionados com os dados da acidez superficial dos catalisadores, indicaram que h? uma redu??o exponencial da Ea da rea??o catal?tica de degrada??o em fun??o da concentra??o dos s?tios ?cidos dos materiais, indicando que esta propriedade ? significativa neste tipo de rea??o
69

Hidrocarbonetos polic?clicos arom?ticos no meio ambiente: diferencia??o de fontes em sedimentos e metab?litos em bile de peixes

Meniconi, Maria de F?tima Guadalupe 30 March 2007 (has links)
Made available in DSpace on 2014-12-17T15:42:31Z (GMT). No. of bitstreams: 1 MariaFGM.pdf: 2684798 bytes, checksum: 4d672e17bab00bdd5d88eb70b9c57edf (MD5) Previous issue date: 2007-03-30 / Petr?leo Brasileiro SA - PETROBRAS / Many studies on environmental ecosystems quality related to polycyclic aromatic hydrocarbons (PAH) have been carried out routinely due to their ubiquotus presence worldwide and to their potential toxicity after its biotransformation. PAH may be introduced into the environmet by natural and anthropogenic processes from direct runoff and discharges and indirect atmospheric deposition. Sources of naturally occurring PAHs include natural fires, natural oil seepage and recent biological or diagenetic processes. Anthropogenic sources of PAHs, acute or chronic, are combustion of organic matter (petroleum, coal, wood), waste and releases/spills of petroleum and derivatives (river runoff, sewage outfalls, maritime transport, pipelines). Besides the co-existence of multiples sources of PAH in the environmental samples, these compounds are subject to many processes that lead to geochemical fates (physical-chemical transformation, biodegradation and photo-oxidation), which leads to an alteration of their composition. All these facts make the identification of the hydrocarbons sources, if petrogenic, pyrolytic or natural, a challenge. One of the objectives of this study is to establish tools to identify the origin of hydrocarbons in environmental samples. PAH diagnostic ratios and PAH principal component analysis were tested on a critical area: Guanabara Bay sediments. Guanabara Bay is located in a complex urban area of Rio de Janeiro with a high anthropogenic influence, being an endpoint of chronic pollution from the Greater Rio and it was the scenario of an acute event of oil release in January 2000. It were quantified 38 compounds, parental and alkylated PAH, in 21 sediment samples collected in two surveys: 2000 and 2003. The PAH levels varied from 400 to 58439 ng g-1. Both tested techniques for origin identification of hydrocarbons have shown their applicability, being able to discriminate the PAH sources for the majority of the samples analysed. The bay sediments were separated into two big clusters: sediments with a clear pattern of petrogenic introduction of hydrocarbons (from intertidal area) and sediments with combustion characteristics (from subtidal region). Only a minority of the samples could not display a clear contribution of petrogenic or pyrolytic input. The diagnostic ratios that have exhibited high ability to distinguish combustion- and petroleum-derived PAH inputs for Guanabara Bay sediments were Phenanthrene+Anthracene/(Phenanthrene+Anthracene+C1Phenanthrene); Fluorantene/(Fluorantene+Pyrene); Σ (other 3-6 ring PAHs)/ Σ (5 alkylated PAH series). The PCA results prooved to be a useful tool for PAH source identification in the environment, corroborating the diagnostic indexes. In relation to the temporal evaluation carried out in this study, it was not verified significant changes on the class of predominant source of the samples. This result indicates that the hydrocarbons present in the Guanabara Bay sediments are mainly related to the long-term anthropogenic input and not directly related to acute events such as the oil spill of January 2000. This findings were similar to various international estuarine sites. Finally, this work had a complementary objective of evaluating the level of hydrocarbons exposure of the aquatic organisms of Guanabara Bay. It was a preliminary study in which a quantification of 12 individual biliar metabolites of PAH was performed in four demersal fish representing three different families. The analysed metabolites were 1-hydroxynaphtalene, 2-hidroxinaphtalene, 1hydroxyphenanthrene, 9-hydroxyphenanthrene, 2-hydroxyphenanthrene, 1hydroxypyrene, 3-hidroxibiphenil, 3- hydroxyphenanthrene, 1-hydroxychrysene, 9hydroxyfluorene, 4-hydroxyphenanthrene, 3-hydroxybenz(a)pyrene. The metabolites concentrations were found to be high, ranging from 13 to 177 ?g g-1, however they were similar to worldwide regions under high anthropogenic input. Besides the metabolites established by the used protocol, it was possible to verified high concentrations of three other compounds not yet reported in the literature. They were related to pyrolytic PAH contribution to Guanabara Bay aquatic biota: 1-hydroxypyrine and 3-hydroxybenz(a)pyrine isomers / In?meros estudos da qualidade de ecossistemas naturais em rela??o a contamina??o de hidrocarbonetos polic?ciclos arom?ticos (HPA) t?m sido desenvolvidos continuadamente face a sua presen?a ub?quoa em todo o planeta e ao seu potencial t?xico ap?s a biotransforma??o. A introdu??o dos HPA no meio ambiente pode ocorrer atrav?s de processos naturais e antropog?nicos, atrav?s de despejos e/ou drenagens e deposi??o atmosf?rica indireta. Fontes naturais de HPA incluem queimadas naturais, exsuda??es de ?leo e processos biog?nicos recentes. Fontes antropog?nicas de HPA, advindas de eventos cr?nicos ou agudos, s?o a combust?o incompleta de ?leo combust?vel automotivo e industrial, a queima intencional de madeira e planta??es, os despejos dom?sticos e industriais, as drenagens pluviais urbanas, os efluentes da ind?stria petrol?fera, os derrames acidentais de ?leo e derivados. Al?m da coexist?ncia de m?ltiplas fontes destes hidrocarbonetos nas amostras ambientais, os HPA est?o sujeitos a v?rios processos geoqu?micos que conduzem ? altera??o de sua composi??o qu?mica ao longo do tempo, tornando a identifica??o das fontes contaminantes, se petrog?nica, pirol?tica ou natural, um verdadeiro desafio. Desta forma, um dos objetivos deste estudo foi estabelecer ferramentas que possibilitem a determina??o das fontes de hidrocarbonetos no meio ambiente. Foram utilizadas raz?es diagn?sticas e an?lise de componentes principais de HPA, tendo sido quantificados 38 compostos, incluindo os HPA parentais e alquilados, em 21 amostras de sedimento da Ba?a de Guanabara, coletadas nos anos de 2000 e 2003. A Ba?a de Guanabara ? um ecossistema estuarino com elevada influ?ncia antropog?nica, que recebe polui??o cr?nica da regi?o metropolitana do Rio de Janeiro e que foi cen?rio de um derrame de ?leo em janeiro de 2000. As concentra??es de HPA nos sedimentos estudados apresentaram-se na faixa de 400 a 58439 ng g-1. Ambas as t?cnicas de diferencia??o de fontes de HPA testadas, raz?es diagn?sticas e an?lise de componentes principais, demonstraram sua aplicabilidade, permitindo a diferencia??o das fontes de HPA para a maioria dos sedimentos da ba?a, que foram divididos em dois grandes grupos: sedimentos com padr?es de introdu??o de hidrocarbonetos predominantemente petrog?nicos e sedimentos com caracter?sticas de combust?o. Apenas uma minoria de amostras n?o apresentou com nitidez a natureza de sua contamina??o. As raz?es que apresentaram maior capacidade em diferenciar as fontes de HPA foram Fluoranteno / (Fluoranteno + Pireno), (Fenantreno + Antraceno) / (Fenantreno + Antraceno + C1Fenantreno) e o ?ndice pirol?tico, Σ (HPA parentais de 3-6 an?is) /Σ (5 s?ries de HPA alquilados). Na avalia??o temporal realizada neste estudo n?o foram verificadas varia??es significativas na natureza das fontes contaminantes predominantes na ba?a, revelando que os hidrocarbonetos presentes est?o correlacionados principalmente com os aportes cr?nicos e n?o diretamente com eventos agudos como o derrame de ?leo ocorrido em janeiro de 2000. Este estudo teve como segundo objetivo a avalia??o preliminar do n?vel de exposi??o a que os organismos aqu?ticos da Ba?a de Guanabara est?o submetidos, atrav?s da quantifica??o de 12 metab?litos individuais de HPA presentes em bile de peixe de quatro esp?cies demersais representativas de tr?s fam?lias diferentes. Os metab?litos analisados foram 1-hidroxinaftaleno, 1-hidroxifenantreno, 9hidroxifenantreno, 2-hidroxinaftaleno, 2-hidroxifenantreno, 1-hidroxipireno, 3hidroxibifenila, 3-hidroxifenantreno, 1-hidroxicriseno, 9-hidroxifluoreno, 4hidroxifenantreno, 3-hidroxibenzo(a)pireno. As concentra??es encontradas nas esp?cies de peixes analisadas mostraram-se elevadas, na faixa de 13 a 177 ?g g1, por?m similares ?s encontradas em algumas regi?es de grande influ?ncia antropog?nica, tanto no Brasil quanto no exterior. Al?m dos metab?litos estabelecidos pela metodologia utilizada, foi poss?vel quantificar tr?s compostos, ainda n?o reportados na literatura, em concentra??es relevantes. Estes metab?litos, relacionados a contribui??o pirol?tica de HPA aos organismos aqu?ticos da Ba?a de Guanabara, s?o is?meros de 1-hidroxipireno e de 3-hidroxibenzo(a)pireno
70

Estudo do processo de combust?o in-situ em reservat?rios maduros de ?leos m?dios e leves (high pressure air injection)

Catonho, Humberto Sampaio 29 July 2013 (has links)
Made available in DSpace on 2014-12-17T14:08:54Z (GMT). No. of bitstreams: 1 HumbertoSC_DISSERT.pdf: 7792135 bytes, checksum: 5204c60825f60e9f74c5f24e46e8aa4e (MD5) Previous issue date: 2013-07-29 / Nearly 3 x 1011 m3 of medium and light oils will remain in reservoirs worldwide after conventional recovery methods have been exhausted and much of this volume would be recovered by Enhanced Oil Recovery (EOR) methods. The in-situ combustion (ISC) is an EOR method in which an oxygen-containing gas is injected into a reservoir where it reacts with the crude oil to create a high-temperature combustion front that is propagated through the reservoir. The High Pressure Air Injection (HPAI) method is a particular denomination of the air injection process applied in light oil reservoirs, for which the combustion reactions are dominant between 150 and 300?C and the generation of flue gas is the main factor to the oil displacement. A simulation model of a homogeneous reservoir was built to study, which was initially undergone to primary production, for 3 years, next by a waterflooding process for 21 more years. At this point, with the mature condition established into the reservoir, three variations of this model were selected, according to the recovery factors (RF) reached, for study the in-situ combustion (HPAI) technique. Next to this, a sensitivity analysis on the RF of characteristic operational parameters of the method was carried out: air injection rate per well, oxygen concentration into the injected gas, patterns of air injection and wells perforations configuration. This analysis, for 10 more years of production time, was performed with assistance of the central composite design. The reservoir behavior and the impacts of chemical reactions parameters and of reservoir particularities on the RF were also evaluated. An economic analysis and a study to maximize the RF of the process were also carried out. The simulation runs were performed in the simulator of thermal processes in reservoirs STARS (Steam, Thermal, and Advanced Processes Reservoir Simulator) from CMG (Computer Modelling Group). The results showed the incremental RF were small and the net present value (NPV) is affected by high initial investments to compress the air. It was noticed that the adoption of high oxygen concentration into the injected gas and of the five spot pattern tends to improve the RF, and the wells perforations configuration has more influence with the increase of the oil thickness. Simulated cases relating to the reservoir particularities showed that smaller residual oil saturations to gas lead to greater RF and the presence of heterogeneities results in important variations on the RF and on the production curves / Aproximadamente 3 x 1011 m3 de ?leos m?dios e leves restar?o nos reservat?rios ao redor do mundo ap?s a aplica??o dos m?todos convencionais de recupera??o e grande parte desse volume seria recuper?vel com o uso de m?todos especiais. A combust?o in-situ (CIS) ? um m?todo de recupera??o avan?ada de petr?leo no qual um g?s que cont?m oxig?nio ? injetado no reservat?rio onde reage com o ?leo cru para criar uma frente de combust?o de alta temperatura que se propaga pelo reservat?rio. O m?todo HPAI (High Pressure Air Injection) ? uma denomina??o particular do processo de inje??o de ar aplicado em reservat?rios de ?leos leves, onde as rea??es de combust?o s?o dominantes entre 150 e 300?C e a gera??o de flue gas ? o principal fator de deslocamento do ?leo. Um modelo de simula??o de fluxo de um reservat?rio homog?neo foi constru?do para o estudo, o qual foi inicialmente submetido ? produ??o prim?ria, por 3 anos, e em seguida, ao processo de inje??o de ?gua por mais 21 anos. Nesse ponto, com a condi??o madura estabelecida no reservat?rio, foram selecionadas tr?s varia??es desse modelo, de acordo com o fator de recupera??o (FR) obtido, para o estudo da t?cnica de combust?o in-situ (HPAI). Em seguida realizou-se uma an?lise de sensibilidade sobre o FR de par?metros operacionais pr?prios do m?todo: vaz?o de inje??o de ar por po?o, concentra??o de oxig?nio no g?s injetado, esquema de inje??o de ar e configura??o dos canhoneados dos po?os. Essa an?lise, para um per?odo adicional de at? 10 anos produ??o, foi efetuada com o aux?lio da t?cnica de planejamento composto central. O comportamento do reservat?rio e os impactos de par?metros envolvendo as rea??es qu?micas e de particularidades de reservat?rio sobre o FR tamb?m foram avaliados. Adicionalmente foram elaborados uma an?lise econ?mica e um estudo de maximiza??o do FR do processo. As simula??es foram realizadas com o simulador de processos t?rmicos em reservat?rios STARS (Steam, Thermal and Advanced Process Reservoir Simulation) da CMG (Computer Modelling Group). Os resultados mostraram que os FR incrementais foram baixos e que o valor presente l?quido (VPL) ? impactado negativamente pelos elevados investimentos iniciais para compress?o do ar. Observou-se que a ado??o de maiores concentra??es de oxig?nio no g?s injetado e do esquema de inje??o de ar tipo five spot tende a favorecer o FR, e que a configura??o dos canhoneados dos po?os apresenta influ?ncia crescente com o aumento da espessura porosa com ?leo do reservat?rio. Casos simulados referentes ?s particularidades de reservat?rio indicaram que menores satura??es residuais de ?leo ao g?s levam a FR maiores e que a exist?ncia de heterogeneidades resulta em varia??es consider?veis nos FR e nas curvas de produ??o

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