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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.
11

Variabilidade de elementos qu?micos de solos em uma ?rea de atua??o da ind?stria petrol?fera, no munic?pio de Ass?-RN, utilizando digest?o ?cida assistida por microondas

Silva, Cosme Oliveira da 31 March 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-04-26T19:29:13Z No. of bitstreams: 1 CosmeOliveiraDaSilva_DISSERT.pdf: 3405424 bytes, checksum: 77af285a8e7c8fecd07283dc05e4ed95 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-04-28T23:43:19Z (GMT) No. of bitstreams: 1 CosmeOliveiraDaSilva_DISSERT.pdf: 3405424 bytes, checksum: 77af285a8e7c8fecd07283dc05e4ed95 (MD5) / Made available in DSpace on 2016-04-28T23:43:19Z (GMT). No. of bitstreams: 1 CosmeOliveiraDaSilva_DISSERT.pdf: 3405424 bytes, checksum: 77af285a8e7c8fecd07283dc05e4ed95 (MD5) Previous issue date: 2014-03-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Nas ?ltimas d?cadas, a preocupa??o com os processos de contamina??o antr?pica do solo por metais e demais contaminantes, vem crescendo significativamente, dessa forma a cada dia, a necessidade de se conhecer a composi??o qu?mica natural dos diversos tipos de solos torna-se cada vez mais constante. Esse conhecimento torna-se importante principalmente para a agricultura, que necessita da quantifica??o de elementos qu?micos, em uma determinada ?rea, uma vez existindo elementos que s?o ambientalmente dispon?veis e necess?rios para o crescimento das plantas. Por?m, existem tamb?m os que s?o considerados t?xicos. O presente trabalho tem como objetivo principal avaliar a variabilidade vertical dos elementos Al, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, P, Ni, Pb, V e Zn, al?m do pH. Comparando duas digest?es HNO3 e HNO3/HCl e duas fra??es < 180 > 63 e < 63 ?m. Para isto, foram coletadas 16 amostras em quatro n?veis amostrais: 0-20 cm,35-55 cm, 70-90 cm e 105-125 cm, localizadas no munic?pio de Ass? ? RN, em uma ?rea situada a cerca de 300 metros a norte da Esta??o de Tratamento de Petr?leo de Estreito (ET-B), operada pela PETROBRAS. Para a valida??o dos dados, realizou-se tamb?m, um estudo estat?stico para avaliar a precis?o e a exatid?o dos dados obtidos. Concluiu-se com esse trabalho, que a maioria dos elementos apresentou uma variabilidade m?dia, sendo que a fra??o mais fina apresentou uma varia??o maior de um n?vel amostral para outro. J? a fra??o mais grossa apresentou uma varia??o menor. Os maiores teores foram encontrados na fra??o mais fina, bem como, os resultados mais eficientes foram encontrados na digest?o com HNO3. / In recent decades, the concern with the processes of contamination soil anthropogenic by metals and other contaminants, is growing significantly, in this way every day, the need to know the natural chemical composition of the various soil types becomes increasingly constant. This knowledge becomes particularly important to agriculture, which requires the quantification of chemical elements in a given area, since there are elements that environmentally available and necessary for plant growth. However, there are also those that are considered toxic. This study aims to evaluate the vertical variability elements of Al, Ca, Co, Cr, Cu, Fe, K, Mg, M, Na, P, Ni, Pb, V and Zn, beyond pH. Comparing two digestions HNO3/HCl HNO3 and two fractions < 180 > 63 and < 63 pm. To this, 16 samples were collected in four sampling levels: 0-20 cm, 35-55 cm, 70-90 cm and 105-125 cm, located in the municipe of Assu - RN in an area located about 300 meters northern Treatment Plant of Oil Estreito (ET - B), operated by PETROBRAS. To validate the data, also was held a statistical study to assess the accuracy and the accuracy of the data. It was concluded from this work that most elements showed an average variability with the finest fraction showed a greater variation from one sample to another level. Have the thickest fraction showed less variation. The highest levels were found in the finest fraction, as well as the most efficient results were found in HNO3 digestion.
12

Estudo da efici?ncia dos adsorventes de Al2O3 e Fe/Al2O3 para remo??o de BTX presente em ?gua contaminada com gasolina

Ara?jo, Nayonara Karolynne Costa de 24 February 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-25T23:22:46Z No. of bitstreams: 1 NayonaraKarolynneCostaDeAraujo_DISSERT.pdf: 1902815 bytes, checksum: 2bb22e78c4a3734579a224d361769b7e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-04T22:29:40Z (GMT) No. of bitstreams: 1 NayonaraKarolynneCostaDeAraujo_DISSERT.pdf: 1902815 bytes, checksum: 2bb22e78c4a3734579a224d361769b7e (MD5) / Made available in DSpace on 2016-08-04T22:29:40Z (GMT). No. of bitstreams: 1 NayonaraKarolynneCostaDeAraujo_DISSERT.pdf: 1902815 bytes, checksum: 2bb22e78c4a3734579a224d361769b7e (MD5) Previous issue date: 2016-02-24 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Este trabalho teve como objetivo avaliar a efici?ncia da remo??o de BTX atrav?s de processos de adsor??o, empregando a alumina (Al2O3) e alumina suportada com ferro (Fe/Al2O3) como adsorventes. Preparou-se uma solu??o sint?tica de gasolina e ?gua destilada para simular uma amostra real. Inicialmente, os adsorventes foram caracterizados pelas t?cnicas DRX, TG/DTG, FRX, FTIR e MEV/EDS. Posteriormente, para a realiza??o dos ensaios, a solu??o sint?tica foi colocada na presen?a do Al2O3 e Fe/Al2O3 em um sistema fechado sob agita??o mec?nica, variando a concentra??o do adsorvente em 2, 4 e 6 g.L-1. A cada 0, 10, 30, 60, 90 e 120 minutos, foram retiradas al?quotas dessa solu??o, e levadas para an?lise atrav?s da t?cnica de cromatografia gasosa por ioniza??o de chama (CG-FID) com extra??o por headspace. Os resultados indicaram que o adsorvente que possui maior capacidade de remo??o de BTX ? o Fe/Al2O3 na concentra??o de 6g.L-1, pH = 4 e no tempo de rea??o de 90 minutos, resultando em uma efici?ncia de 86,5% de remo??o para o benzeno, 95,4% para o tolueno, 90,8% para os ?,?- Xilenos e 93,7% para os ?-Xilenos . Encontradas as condi??es ?timas nos ensaios de adsor??o, foi realizado um estudo cin?tico das rea??es, os resultados mostraram que os valores da capacidade de adsor??o experimental (qe) apresentaram concord?ncia com os valores da capacidade de adsor??o te?rica (qc) calculados para o modelo pseudo-segunda ordem para os ensaios de adsor??o de 2 e 6 g.L-1 utilizando Al2O3 e para todos os ensaios utilizando Fe/Al2O3. Fato corroborado pelos valores de R2, que justificam a representa??o dos dados pelo modelo de segunda ordem, indicando assim que as intera??es qu?micas est?o presentes nos mecanismos de adsor??o dos BTX na Al2O3. / Contamination of groundwater by BTX has been featured in recent decades. This type of contamination is due to small and continuous leaks at gas stations, causing serious problems to public health and the environment. Based on these antecedents, the search for new alternatives for treating contaminated water is shown to be essential. Therefore, this study aimed to evaluate the efficiency of removal of BTX by adsorption processes employing commercial alumina (Al2O3) and alumina supported with iron (Fe/Al2O3) as adsorbents. It was prepared by a in a synthetic gasoline solution and distilled water to simulate an actual sample. Initially, the adsorbents were characterized by techniques XRD, TG / DTG, XRF, FTIR and SEM/EDS, several trials, where he was placed synthetic solution to react in the presence of Al2O3 and Fe/Al2O3 in a closed, mechanical stirring system were performed varying the catalyst concentration 2, 4 and 6 g.L-1 every 0, 10, 30 60, 90 and 120 min, aliquots were taken and brought to analysis by gas chromatography flame ionization with headspace extraction. The results indicated that the absorbent which has higher BTX removal capacity was the Fe/Al2O3 at a concentration of 6 g.L-1, pH = 4 and time of 90 minutes reaction, resulting in an efficiency, resulting in a 86,5% efficiency for benzene removal, for the 95,4% toluene, 90,8% for ?,?- xylene and 93.7% for the ?-xylenes. Subsequently, we performed a kinetic study of the reactions, the values of experimental adsorption capacity (qe) showed agreement with the values of the theoretical adsorption capacity (qc) to the pseudo-second-order model in the adsorption tests using 2 and 6 gL-1 of Al2O3 and assays using 2, 4 and 6 g.L-1 of Fe/Al2O3. A fact corroborated by the R2 values, thus indicating that the chemical interactions are present in the adsorption mechanisms of BTX.
13

Calcretes pedog?nicos ao longo de sistemas de fraturas e acamamentos em carbonatos neoproteroz?icos da Bacia de Irec?, Estado da Bahia

Borges, S?rgio Vieira Freire 19 August 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-10T16:44:41Z No. of bitstreams: 1 SergioVieiraFreireBorges_TESE.pdf: 7086873 bytes, checksum: 8a52c6c1ff325db416f723593fd8f762 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-10T21:45:09Z (GMT) No. of bitstreams: 1 SergioVieiraFreireBorges_TESE.pdf: 7086873 bytes, checksum: 8a52c6c1ff325db416f723593fd8f762 (MD5) / Made available in DSpace on 2017-02-10T21:45:09Z (GMT). No. of bitstreams: 1 SergioVieiraFreireBorges_TESE.pdf: 7086873 bytes, checksum: 8a52c6c1ff325db416f723593fd8f762 (MD5) Previous issue date: 2016-08-19 / Calcretes ou caliches s?o calc?rios continentais gerados pelos processos de intemperismo que ocorrem principalmente em regi?es ?ridas e semi-?ridas. Na Bacia de Irec?, localizada no norte do estado da Bahia, al?m da ocorr?ncia regular de calcretes pedog?nicos, um tipo peculiar de calcretes ocorre dentro dos calc?rios neoproteroz?icos da bacia. Estes calcretes desenvolveram-se perto da superf?cie e (1) entre as camadas sedimentares dos calc?rios, (2) dentro dos sistemas de fraturas e (3) dentro das principais falhas de empurr?o. Trabalhos de campo em afloramentos selecionados foram integrados com an?lises petrogr?ficas, mineral?gicas, geoqu?micas, c?lculos de densidade e porosidade por intrus?o de merc?rio para entender seu ambiente de forma??o e suas propriedades petrof?sicas. Os resultados revelaram que este tipo de calcrete ? o produto de eventos multiepis?dicos de dissolu??o e precipita??o ocorridos durante as esta??es secas e chuvosas na regi?o. Os estudos petrof?sicos sugerem que estes calcretes t?m um papel importante na migra??o de fluidos atrav?s de uma rocha hospedeira carbon?tica imperme?vel e que atuam como condutos para o fluxo de fluido, como revelado pela sua alta porosidade (valor m?dio de 26%) e not?vel conectividade de poros.
14

Simulador semianal?tico para fluxo em reservat?rios homog?neos fechados utilizando a solu??o da fonte pontual aplicada ao m?todo de elementos de contorno

Ara?jo, Rodrigo Moreira 12 August 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-13T20:20:42Z No. of bitstreams: 1 RodrigoMoreiraAraujo_DISSERT.pdf: 4010692 bytes, checksum: 14265a10e5cf460156263b3eb9ab5525 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-16T19:42:17Z (GMT) No. of bitstreams: 1 RodrigoMoreiraAraujo_DISSERT.pdf: 4010692 bytes, checksum: 14265a10e5cf460156263b3eb9ab5525 (MD5) / Made available in DSpace on 2017-02-16T19:42:17Z (GMT). No. of bitstreams: 1 RodrigoMoreiraAraujo_DISSERT.pdf: 4010692 bytes, checksum: 14265a10e5cf460156263b3eb9ab5525 (MD5) Previous issue date: 2016-08-12 / Esta disserta??o apresenta um simulador semi-anal?tico de fluxo em reservat?rios homog?neos fechados atrav?s da aplica??o do m?todo de elementos de contorno (Boundary Element Method - BEM) utilizando a solu??o da fonte pontual em reservat?rio infinito. Este m?todo ? conhecido por prover vantagens valiosas sobre outros m?todos de discretiza??o de dom?nios, como a redu??o no esfor?o de discretiza??o quando comparado ao m?todo de elementos finitos. A implementa??o foi feita na linguagem de programa??o Python associada a bibliotecas amplamente testadas e utilizadas em aplica??es cient?ficas. Os resultados foram validados atrav?s de um simulador semi-anal?tico de funcionamento comprovado e demonstraram-se vi?veis para todos os cen?rios estudados. / Solving the problem of fluid flow inside closed reservoirs holds great importance for the oil industry as it allows field managers to evaluate oil producing fields and supplies data to infer production and income. One of the most common ways to solve this problem is by using the Images Method, which models closed barriers as image wells, but requires excessive processing power as it depends on the convergence of sums of infinite series. As an alternative to the Images Method, this work presents a semi-analytical simulator for monophasic and laminar fluid flow on closed, homogeneous and isotropic reservoirs based on the Boundary Element Method (BEM) associated with the Green?s function for a point source in an infinite reservoir as the fundamental solution. This method has known advantages over other numerical methods including, mainly, the reduction on discretization efforts. This work applies the Python programming language associated to scientific libraries, thoroughly tested and applied on this area. The simulator was tested on 5 different scenarios (well on infinite reservoir, well on small and large reservoir, and well decentralized on 1 and 2 axis) and was validated through another semi-analytical simulator whose results were already thoroughly tested. On all scenarios, the simulator achieved correlation values of more than 95%.
15

Sensoriamento remoto em suporte ao mecanismo de desenvolvimento limpo (MDL) em manguezais do litoral setentrional do Rio Grande do Norte, Brasil

Costa, Bruno Cesar Pereira da 18 November 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-04-17T23:16:01Z No. of bitstreams: 1 BrunoCesarPereiraDaCosta_TESE.pdf: 9035673 bytes, checksum: b47a178b546c68bed34b29cd6050cae3 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-04-20T22:33:39Z (GMT) No. of bitstreams: 1 BrunoCesarPereiraDaCosta_TESE.pdf: 9035673 bytes, checksum: b47a178b546c68bed34b29cd6050cae3 (MD5) / Made available in DSpace on 2017-04-20T22:33:39Z (GMT). No. of bitstreams: 1 BrunoCesarPereiraDaCosta_TESE.pdf: 9035673 bytes, checksum: b47a178b546c68bed34b29cd6050cae3 (MD5) Previous issue date: 2016-11-18 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / As imagens de sat?lites t?m sido utilizadas para mapear, monitorar e quantificar a qualidade dos recursos naturais. O mapeamento detalhado da vegeta??o de mangue ? uma demanda crescente por se tratar de um valoroso instrumento de conhecimento, manuten??o e gest?o do ecossistema manguezal em rela??o ?s modifica??es provocadas pelas atua??es antr?picas e/ou naturais, frente ?s mudan?as globais. Este trabalho combinou dados multiespectrais da regi?o do vis?vel e infravermelho pr?ximo do sistema LANDSAT-8 com dados monoespectrais do RADARSAT-2, aliado a dados hiperespectrais de espectrorradiometria e ?ndice de Vegeta??o na segmenta??o e classifica??o de alguns manguezais no Nordeste do Brasil, levando em considera??o a diversidade de ambientes presentes na ?rea total do estudo. Como resultado final do processo de segmenta??o e classifica??o, calculamos que os manguezais da ?rea estudada ocupam ?rea total de aproximadamente 5.392 ha. A esp?cie R. mangle ? a esp?cie dominante, totalizando uma ?rea de 3.350 ha, representando 62,13% da ?rea total, deste total cerca de 2.861 ha s?o ocupados pela R. mangle I (porte e adensamento convencional), representando 53,06% da ?rea total; 489 ha pela condi??o fitoestrutural R. mangle II (porte baixo e bastante adensado), cerca de 9,07% da ?rea total; regi?es mistas de esp?cies ou de transi??o entre elas ocupam ?rea de 1.092 ha, cerca de 20,25% da ?rea total, seguida da esp?cie A. schaueriana ocupando uma ?rea de 950 ha, cerca de 17,62% da ?rea total. Este estudo atendeu ?s expectativas em obter uma maior efici?ncia no levantamento espacial com alta acur?cia para o monitoramento da qualidade desse ecossistema altamente sens?vel ?s altera??es ambientais: como subs?dio ? sua preserva??o e transforma??o em um Projeto de Mecanismo de Desenvolvimento Limpo. Para tal, foi realizada a estimativa de CO2 aprisionado nas florestas de mangue pertencentes a Reserva de Desenvolvimento Sustent?vel Estadual Ponta do Tubar?o (RDSEPT) por meio de M?todo Indireto n?o destrutivo. As estimativas totais das m?dias de CO2 aprisionado em cada hectare ocupado pela esp?cie R. mangle ? de 39,93 t, L. schaueriana ? de 28,47 t e as regi?es de esp?cies mistas ? de 34,20 t. Estima-se que a quantifica??o total de CO2 aprisionado na RDSEPT seja 17.156,51 t. Mediante os valores obtidos, percebemos que o manguezal da RDSEPT de maneira geral possui um grande potencial de gerar biomassa e consequentemente aprisionar CO2. Podendo gerar uma valiosa oportunidade financeira, justificando a preserva??o deste ecossistema. / The satellite images have been used to map, monitor and quantify the quality of natural resource. The detailed mapping of mangrove vegetation is an increasing demand because it is a valorous Valorous instrument of knowledge, maintenance and management of the mangrove ecosystem in relation to changes caused by anthropic actions and/or natural activities to global changes. This work combined multispectral data from the visible and near infrared of the LANDSAT-8 system with Monospectral data from RADARSAT-2, combined with hyperspectral data of the spectroradiometry and Vegetation Index in the segmentation and classification of some mangroves in the Northeast of Brazil, taking into account the diversity of environments present in the total area of the study. As the final result of the segmentation and classification process, we calculate that the mangroves in the study area occupy a total area of approximately 5.392ha. The species R. mangle is the dominant species, totaling an area of 3,350 ha, representing 62.13% of the total area, of this total about 2,861 ha are occupied by R. mangle I (size and conventional densification), representing 53.06% of the total area; 489 ha for structural phyto condition R. mangle II (short stature and very dense), about 9.07% of the total area; mixed regions of species or transition between them occupy area of 1092 ha, about 20.25% of total area, then the specie A. schaueriana occupying an area of 950 ha, about 17.62% of the total area. This study met the expectations to get the greater efficiency in the spatial lifting for monitoring the quality of this highly sensitive ecosystem on the environmental changes: as support their preservation and transformation into a Clean Development Mechanism Project. For such, was made the estimation of trapped CO2 in mangrove forests belonging to Reserva de Desenvolvimento Sustent?vel Estadual Ponta do Tubar?o (RDSEPT) by Indirect Method nondestructive. The total estimates on the mean of trapped CO2 in each hectare occupied by the species R. mangle is 39.93t, L. schaueriana is 28.47t and the regions of mixed species is 34.20t. It is estimated that the total quantification of trapped CO2 in the RDSEPT is 17156.51t. By the obtained values, we realized that the values of mangrove in the RDSEPT in general have a great potential to generate biomass and consequently imprison CO2. It is able to generate a valuable financial opportunity, justifying the preservation of this ecosystem.
16

Efeito da adi??o de filler a base de res?duo do polimento do porcelanato e dispers?o aquosa de poliuretana na permeabilidade de pastas de cimento

Sousa J?nior, Almir Mariano de 29 December 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-05-31T20:47:35Z No. of bitstreams: 1 AlmirMarianoDeSousaJunior_TESE.pdf: 3946108 bytes, checksum: 2bc096f2c4d458f0f8b935b7ab096360 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-06-01T21:12:03Z (GMT) No. of bitstreams: 1 AlmirMarianoDeSousaJunior_TESE.pdf: 3946108 bytes, checksum: 2bc096f2c4d458f0f8b935b7ab096360 (MD5) / Made available in DSpace on 2017-06-01T21:12:03Z (GMT). No. of bitstreams: 1 AlmirMarianoDeSousaJunior_TESE.pdf: 3946108 bytes, checksum: 2bc096f2c4d458f0f8b935b7ab096360 (MD5) Previous issue date: 2016-12-29 / A mudan?a da matriz energ?tica ? algo ainda muito longe da realidade atual, surgindo o armazenamento geol?gico como alternativa contra o aquecimento global, adotando a t?cnica de captura de CO2 e CH4 antes de sua emiss?o para a atmosfera. Destacam-se como ambientes de armazenamento dos gases, os campos de explora??o maduros de petr?leo e abandonados, contudo, surge a necessidade de desenvolver pastas de ciment?cias sustent?veis para tamponamento de po?os que possuam baixa permeabilidade, buscando minimizar a emiss?o dos referidos gases para a atmosfera. Estas foram desenvolvidas com adi??o de filler do res?duo do polimento do porcelanato (RPP) e dispers?o aquosa de poliuretana, objetivando analisar o seu efeito na redu??o de permeabilidade em pastas de cimento para tamponamento de po?os de petr?leo. Para identificar o melhor comportamento, realizou-se ensaios de permeabilidade, resist?ncia ? compress?o axial, estabilidade, densidade e carbonata??o de acordo com as especifica??es da Associa??o Brasileira de Normas T?cnicas (ABNT) e do American Petroleum Institute (API). Os resultados obtidos nos ensaios foram satisfat?rios e verificou-se que as adi??es do Res?duo do Polimento do Porcelanato e da Poliuretana contribu?ram para redu??o da permeabilidade em pastas de cimento, possuem uma boa resist?ncia a compress?o e conseguem resistir a condi??es carbon?tica com 60 dias de exposi??o em ambiente supercr?tico. / The change in the energy matrix is still far from the current reality, then, the geological storage appears as an alternative against the Global Warming, adopting the technique of capturing CO2 and CH4 before their emission into the atmosphere. They stand out as gas storage environments: the mature and abandoned oil fields. However, there is the necessity to develop sustainable cement pastes for the wells cementation with low permeability, in order to minimize the emission of these gases into the atmosphere. These pastes were developed with the addition of filler from the porcelain polishing waste and Water-borne polyurethane in order to analyze theirs effect on the reduction of the permeability in cement pastes for oil wells. To identify the best behavior, permeability, axial compressive strength, stability, density and carbonation, experiments were performed according to the Brazilian Association of Technical Standards (ABNT) and the American Petroleum Institute (API) specifications. The results obtained in the tests were satisfactory and it was verified that the additions of the porcelain polish residue and the Polyurethane contributed to the reduction of the permeability in cement pastes, they have a good resistance to compression and they are able to withstand the carbonate conditions with 60 days of exposure in a supercritical environment.
17

An?lises da molhabilidade e da adsor??o de tensoativos em rocha calc?ria

Neves, Allan Martins 28 June 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-08-01T14:05:21Z No. of bitstreams: 1 AllanMartinsNeves_DISSERT.pdf: 2153659 bytes, checksum: 19b8e265b34574f2712c75f067e65296 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-08-07T15:28:10Z (GMT) No. of bitstreams: 1 AllanMartinsNeves_DISSERT.pdf: 2153659 bytes, checksum: 19b8e265b34574f2712c75f067e65296 (MD5) / Made available in DSpace on 2017-08-07T15:28:10Z (GMT). No. of bitstreams: 1 AllanMartinsNeves_DISSERT.pdf: 2153659 bytes, checksum: 19b8e265b34574f2712c75f067e65296 (MD5) Previous issue date: 2017-06-28 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / O cen?rio atual da ind?stria do petr?leo envolve explorar e produzir reservas com desafios t?cnicos enormes. Desta forma, torna-se cada vez mais necess?rio o conhecimento dos mecanismos que impactam a produ??o do ?leo. Um exemplo disso s?o as novas descobertas no mar brasileiro, como o pr?-sal, composto por grandes acumula??es de ?leo leve, com alto valor comercial. Um fator determinante a ser considerado ? o tipo de rocha reservat?rio predominante na forma??o destas reservas, que s?o rochas carbon?ticas, principalmente o calc?rio, que em sua maioria apresenta molhabilidade favor?vel ao ?leo, fator que diminui a recupera??o do petr?leo. Assim, estudos v?m sendo desenvolvidos com esse tipo de rocha visando inverter sua molhabilidade e melhorar a produtividade. Uma maneira de melhorar essas condi??es no reservat?rio ? atrav?s dos m?todos qu?micos envolvendo tensoativos, que pela sua natureza anfif?lica, t?m a capacidade de se adsorver em interfaces e superf?cies de acordo com sua afinidade, diminuindo a energia livre interfacial, podendo inverter a molhabilidade da rocha, facilitando o fluxo de ?leo e assim, melhorando sua recupera??o. O objetivo desse trabalho foi estudar como diferentes tipos de tensoativos se adsorvem na rocha calc?ria, e se eram capazes de alterar sua molhabilidade. Para isso, foi utilizado o m?todo de banho finito para tr?s tensoativos: OCS (ani?nico), C16TAB (cati?nico) e ULTRANEX 110 (n?o i?nico), variando-se par?metros como a temperatura, a massa de adsorverte (calc?rio), tempo de contato e concentra??o de tensoativo. Tamb?m foram feitas an?lises de ?ngulo de contato para analisar a molhabilidade e de potencial zeta. O OCS foi o ?nico tensoativo que apresentou adsor??o significativa na rocha, possivelmente por apresentar ?ons opostamente carregados aos da rocha. O aumento da temperatura de 30?C para 50?C ocasionou decr?scimo na capacidade de adsor??o. O calc?rio in natura apresentou molhabilidade mista, com forte afinidade ao ?leo, que ap?s tratamento ocorreu diminui??o da molhabilidade ao ?leo, no entanto tamb?m diminuiu em rela??o ? ?gua. As medidas de potencial zeta mostraram que as atra??es eletrost?ticas desempenharam papel importante na adsor??o, obtendo-se maior valor em m?dulo para o OCS. / The current scenario of the oil industry involves exploring and producing reserves with big technical challenges, in this way, it becomes increasingly necessary to know the mechanisms that impact the oil production. An example of this is the new discoveries in the Brazilian sea, with the pre-salt, composed of large accumulations of high commercial value light oil. However, a determining factor to be considered is the type of reservoir rock predominant in the formation of its reserves. These rocks are composed almost of carbonates of calcium that form the carbonate rocks, mainly limestone, which in the majority of them are oil-wet, a factor that Decreases the recovery of oil. Thus, studies have been developed in this type of rock in order to reverse its wettability and improve productivity. One way of change the wettability of the reservoir is through the chemical methods involving surfactants, which by their amphiphilic nature have the ability to adsorb at interfaces and surfaces according to their affinity, reducing the free interfacial energy, which can reverse the wettability of the rock, facilitating the flow of oil and thus, improving its recovery. The objective of this work was to study how different types of surfactants adsorb in limestone, and if they were able to alter their wettability. For this, the finite bath method was used for three surfactants: OCS (anionic), C16TAB (cationic) and ULTRANEX 110 (nonionic), varying parameters such as temperature, adsorption mass (limestone), contact time and concentration of surfactant. Contact angle analysis was also performed to analyze wettability and zeta potential. OCS was the only surfactant that presented significant adsorption in the rock, possibly due to the presence of electrically charged ions. The increase in temperature from 30 ? C to 50 ? C caused a decrease in the adsorption capacity. The limestone in natura presented mixed wettability, with strong affinity to the oil, after treatment the wettability decreased to oil, however it also decreased in relation to water. The measurements of zeta potential showed that the eletrostatic attractions played an important role in the adsorption, obtaining greater value in the module for the OCS.
18

Modelagem da velocidade de um PIG instrumentado usando redes neurais artificiais

Ara?jo, Renan Pires de 22 June 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-08-01T14:05:21Z No. of bitstreams: 1 RenanPiresDeAraujo_DISSERT.pdf: 4838615 bytes, checksum: 6a4a4de336f3ed012ff9d79a80113a5c (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-08-07T15:40:48Z (GMT) No. of bitstreams: 1 RenanPiresDeAraujo_DISSERT.pdf: 4838615 bytes, checksum: 6a4a4de336f3ed012ff9d79a80113a5c (MD5) / Made available in DSpace on 2017-08-07T15:40:48Z (GMT). No. of bitstreams: 1 RenanPiresDeAraujo_DISSERT.pdf: 4838615 bytes, checksum: 6a4a4de336f3ed012ff9d79a80113a5c (MD5) Previous issue date: 2017-06-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A passagem de um PIG ? uma t?cnica bastante empregada na inspe??o de dutos de longo comprimento e principalmente enterrados, valendo-se do diferencial de press?o sobre o mesmo para impulsion?-lo. Por?m, durante a inspe??o, um dos problemas que pode ocorrer ? a parada do PIG por causa de incrusta??es severas ou defeitos de fabrica??o/instala??o dos dutos, fazendo com que o instrumento pare e sua posterior libera??o com altas velocidades devido ao ac?mulo de press?o ? montante. Este trabalho prop?e o uso de redes neurais artificiais a fim de modelar a rela??o entre o diferencial de press?o sobre o PIG e sua velocidade durante o seu trajeto no interior do duto. Para tanto, foi empregado um sistema supervis?rio para a captura dos dados de press?o ao longo da tubula??o de teste e um od?metro acoplado ao PIG para a dos dados de velocidade. Foram considerados dois modelos de redes neurais artificiais, no caso a rede MLP e a rede NARX, sendo esta ?ltima uma rede recursiva. Os resultados de treinamento e valida??o mostraram que os modelos por redes neurais artificiais foram eficientes para estimar a velocidade do PIG. / The passage of a PIG is a technique quite used in inspection of big length and principally buried pipes using the pressure differential on it to impulse itself. But, during the inspection, one of the problems that may occur is the stop of the PIG because of severe incrustations or fabrication/installation defects of the pipes, doing the halt of the instrument and its posterior release with high velocities due to the accumulate of pressure at back part. This work purpose the use of neural networks in order to model the relation between the differential pressure on the PIG and its velocity during your path in the tube. Therefore, it was used a supervisory system to capture the pressure data along the test pipe and an odometer coupled to the PIG for the velocity data. It was considered two neural network models, in the case the MLP and NARX networks, the latter being a recurrent network. The training and validation results showed that the models by neural networks were efficient to estimate the velocity of the PIG.
19

Otimiza??o de metodologia para determina??o de enxofre na forma de sulfato em petr?leo pesado por cromatografia de ?ons

Galv?o, ?lvaro Gustavo Paulo 30 June 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-09-05T19:25:25Z No. of bitstreams: 1 AlvaroGustavoPauloGalvao_DISSERT.pdf: 2667387 bytes, checksum: 5bf60c0285a5be566d4b19dddc68fd68 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-09-13T21:41:06Z (GMT) No. of bitstreams: 1 AlvaroGustavoPauloGalvao_DISSERT.pdf: 2667387 bytes, checksum: 5bf60c0285a5be566d4b19dddc68fd68 (MD5) / Made available in DSpace on 2017-09-13T21:41:06Z (GMT). No. of bitstreams: 1 AlvaroGustavoPauloGalvao_DISSERT.pdf: 2667387 bytes, checksum: 5bf60c0285a5be566d4b19dddc68fd68 (MD5) Previous issue date: 2017-06-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Enxofre ? o terceiro elemento mais abundante no petr?leo e ? considerado um dos principais contaminantes presentes nessa matriz, podendo ocorrer nas formas de sulfetos, tiofenos, mol?culas polic?clicas contendo oxig?nio e nitrog?nio etc. Podem provocar corros?o, envenenamento de catalisadores automotivos e de processos do refino. Na queima dos combust?veis, quando presentes, d?o origem aos ?xidos SOX, que contribuem com a forma??o da chuva ?cida, acidez do solo e problemas respirat?rios na popula??o. Logo, a determina??o de enxofre ? de primordial interesse tanto para a ind?stria petroqu?mica quanto na ?rea da qu?mica anal?tica. Diante dessa conjuntura, ? proposto neste trabalho o desenvolvimento de um procedimento de preparo de amostras de petr?leo para determina??o por Cromatografia de ?ons (IC) do teor de enxofre como sulfato (SO4 2-). Para tal, a decomposi??o por via ?mida em sistema fechado assistida por radia??o micro-ondas, auxiliada pela a??o oxidativa de H2O2, foi o procedimento adotado, onde a temperatura e pot?ncia m?xima de 230 ?C e 1000 W, respectivamente, foram utilizadas no programa de aquecimento. Seis amostras de petr?leo (?API entre 18,75-25,17) foram analisadas, sendo as concentra??es m?dias de enxofre obtidas entre 377,50 e 3321,74 mg Kg-1, com DP entre ? 1,02 e ? 9,56. Para efeitos da avalia??o dos resultados obtidos, realizou-se a determina??o do teor de enxofre nas amostras em estudo utilizando a t?cnica UVF, fundamentada na norma oficial ASTM D5453-12, onde correla??es entre 85,43 e 106,43% foram alcan?adas, evidenciando a efici?ncia do m?todo proposto na convers?o das esp?cies de enxofre contidas nas amostras a sulfato e sua determina??o por IC. A efici?ncia do procedimento de decomposi??o adotado foi testada atrav?s do RCC% e do EOMD%, sendo alcan?ados teores entre 6,72 e 15,73% e 85,85 e 94,14%, respectivamente, demonstrando a efici?ncia do procedimento de decomposi??o utilizado. / Sulfur is the third most abundant element in petroleum and is considered one of the main contaminants present in this matrix, and may occur in the forms of sulfides, thiophenes, polycyclic molecules containing oxygen and nitrogen etc. They can cause corrosion, poisoning of catalysts used in refining and in automobiles. In fuel combustion, when present, they give rise to SOX oxides, which contribute to the formation of acid rain, soil acidity and respiratory problems in the population. Therefore, the determination of sulfur is of primary interest for the petrochemical industry as well as for analytical chemistry. Considering this situation, it is proposed the development of a procedure for the preparation of petroleum samples for the determination of the sulfur content of sulfur (SO4 2-) by Ion Chromatography (IC). For this, the wet decomposition assisted by microwave radiation, assisted by the oxidative action of H2O2, was the adopted procedure, where the maximum temperature and power of 230 ?C and 1000 W, respectively, were used in the program of heating. Six petroleum samples (?API between 18.75-5.17) were analyzed, with the mean concentrations of sulfur being between 377.50 and 3321.74 mg Kg-1, with a standard deviation between ? 1.02 and ? 9.56. For the purposes of the evaluation of the obtained results, the sulfur content in the samples under study was evaluated using the UVF technique, based on the official standard ASTM D 5453-12, where correlations between 85.43 and 106.43% were reached, evidencing the efficiency of the method proposed in the conversion of the sulfur species contained in the samples to sulfate and its determination by IC. The efficiency of the adopted decomposition procedure was tested using RCC% and EDMO%, with levels between 6.72 and 15.73% and 85.85 and 94.14% being respectively achieved, demonstrating the efficiency of the decomposition procedure used.
20

Estudo petrogr?fico e petrol?gico da Forma??o Tombador, Mesoproteroz?ico da Chapada Diamantina, Bahia

Souza, Arn?bio Silva de 03 July 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-09-05T19:25:26Z No. of bitstreams: 1 ArnobioSilvaDeSouza_DISSERT.pdf: 5771102 bytes, checksum: 83f601b7701ab9229184a97dbff2ea8e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-09-13T21:57:43Z (GMT) No. of bitstreams: 1 ArnobioSilvaDeSouza_DISSERT.pdf: 5771102 bytes, checksum: 83f601b7701ab9229184a97dbff2ea8e (MD5) / Made available in DSpace on 2017-09-13T21:57:43Z (GMT). No. of bitstreams: 1 ArnobioSilvaDeSouza_DISSERT.pdf: 5771102 bytes, checksum: 83f601b7701ab9229184a97dbff2ea8e (MD5) Previous issue date: 2017-07-03 / Os dep?sitos silicicl?sticos da Forma??o Tombador, unidade basal do Grupo Chapada Diamantina, de idade mesoproteroz?ica, ocorrem numa faixa aproximadamente Norte-Sul ao longo da Serra do Sincor?, por??o central do Cr?ton S?o Francisco (CSF), Nordeste do Brasil. Esses dep?sitos s?o constitu?dos por uma espessa sequ?ncia de rochas silicicl?sticas. Realizou-se um estudo petrogr?fico e petrol?gico de se??es delgadas de rochas aflorantes da Fm. Tombador, juntamente com o aux?lio de t?cnicas especiais como a Fluoresc?ncia de Raios X (FRX), Difratometria de Raios X (DRX), Espectroscopia de Raios X por Dispers?o de Energia (EDS) e Microscopia Eletr?nica de Varredura (MEV). Com base nas an?lises, verificou-se que essas rochas s?o constitu?das predominantemente por metarenitos. Os seguintes eventos diagen?ticos foram identificados: infiltra??o mec?nica de argilas, compacta??o mec?nica, compacta??o qu?mica, sobrecrescimento de quartzo, sobrecrescimento de turmalina, fraturamento de gr?os, precipita??o de ?xido/hidr?xidos de ferro, dissolu??o de gr?os, cauliniza??o e ilitiza??o. Foram identificados atrav?s da FRX em amostra total, os seguintes elementos qu?micos em ordem decrescente, sil?cio (Si), alum?nio (Al), pot?ssio (K), ferro (Fe), magn?sio (Mg), tit?nio (Ti), zirc?nio (Zr), estr?ncio (Sr) e ?trio (Y). A alta concentra??o do sil?cio (Si), acima de 90% ? decorrente da abund?ncia do quartzo (Q95F3FR2, segundo Folk, 1974), sendo importante indicador da alta maturidade mineral?gica das rochas estudadas. Atrav?s da t?cnica de DRX, foram identificados os seguintes grupos de argilominerais: ilita, caulinita, esmectita e interestratificados de ilita/esmectita. Embora as caracter?sticas das amostras reflitam as condi??es pret?ritas de ambientes diagen?ticos, as medidas do ?ndice de cristalinidade da ilita ou ??ndice de Kubler? (KI), e a presen?a do mineral pirofilita s?o suficientes para demonstrar que as rochas da ?rea de estudo foram afetadas pelo anquimetamorfismo, indicativo da transi??o entre a f?cies prehnita-pumpelita superior e a f?cies xisto verde inferior, e que as condi??es de soterramento atingiram a profundidade da ordem de 10-12 km e temperaturas da ordem de ?300 0C. A ocorr?ncia de determinados argilominerais (ilita, caulinita e esmectita), o alto teor de quartzo, os baixos teores de feldspato e fragmentos de rochas est?o diretamente relacionado aos sistemas deposicionais, mostrando que a composi??o do arcabou?o ? diretamente respons?vel pela evolu??o diagen?tica dessas rochas. / The siliciclastic deposits of the Tombador Formation, basal unit of the Chapada Diamantina Group, of mesoproterozoic age, occur in a north-south range along the Serra do Sincor?, central portion of the S?o Francisco Craton (CSF), Northeast Brazil. These deposits consist of a thick sequence of siliciclastic rocks. A petrographic and petrological study of thin sections of outcropping rocks of Fm. Tombador was carried out, along with the help of special techniques such as X-Ray Fluorescence (FRX), X-ray Diffraction (XRD), X-ray Spectroscopy by Energy Dispersion (EDS) and Scanning Electron Microscopy (SEM). Based on the analyzes, it was verified that these rocks are constituted predominantly by meta-sandstones. The following diagenetic events were identified: mechanical infiltration of clays, mechanical compaction, chemical compaction, quartz overgrowth, tourmaline overgrowth, grain fracturing, iron oxide/hydroxide precipitation, grain dissolution, kaolinization, ilitization and mineral pyrophyllite that reflects the transition stages between diagenesis and anchemimorphism. The following chemical elements in descending order, Si, Al, K, Fe, Mg, Ti, Zr, Sr and Y were identified by X - ray fluorescence in total sample, with values above 85%, together with the high amount of Quartz (Q95F3FR2, according to Folk, 1974), indicate the high mineralogical maturity of these rocks. Through the XRD technique, the following groups of clay minerals were identified: illite, kaolinite, smectite, interstratified of illite/smectite and the mineral pyrophyllite. Although the characteristics of the samples reflect the previous conditions of diagenetic environments, measurements of the illite crystallinity index or "Kubler Index" (KI), and the presence of the mineral pyrophyllite are sufficient to demonstrate that the rocks of the study area were affected by anchemimorphism, indicative of the transition between the prehnita-pumpellyite facies and the below greenschist facies, and that burial conditions reached a depth of the order of 10-12 km and temperatures in the order of ? 300 ? C. The occurrence of certain clay minerals is directly related to the depositional system, showing that the composition of the framework are directly responsible for the diagenetic evolution of these rocks.

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