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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.
1

Tratamento de borra de petr?leo com sistemas microemulsionados

Viana, Flavia Freitas 25 July 2013 (has links)
Made available in DSpace on 2014-12-17T15:42:11Z (GMT). No. of bitstreams: 1 FlaviaFV_DISSERT.pdf: 2036904 bytes, checksum: e98751260e3e63445acf4cc13e184f1f (MD5) Previous issue date: 2013-07-25 / During the storage of oil, sludge is formed in the bottoms of tanks, due to decantation, since the sludge is composed of a large quantity of oil (heavy petroleum fractions), water and solids. The oil sludge is a complex viscous mixture which is considered as a hazardous waste. It is then necessary to develop methods and technologies that optimize the cleaning process, oil extraction and applications in industry. Therefore, this study aimed to determine the composition of the oil sludge, to obtain and characterize microemulsion systems (MES), and to study their applications in the treatment of sludge. In this context, the Soxhlet extraction of crude oil sludge and aged sludge was carried out, and allowing to quantify the oil (43.9 % and 84.7 % - 13 ?API), water (38.7 % and 9.15 %) and solid (17.3 % and 6.15 %) contents, respectively. The residues were characterized using the techniques of X-ray fluorescence (XRF), Xray diffraction (XRD) and transmission Infrared (FT-IR). The XRF technique determined the presence of iron and sulfur in higher proportions, confirming by XRD the presence of the following minerals: Pyrite (FeS2), Pyrrhotite (FeS) and Magnetite (Fe3O4). The FT-IR showed the presence of heavy oil fractions. In parallel, twelve MES were prepared, combining the following constituents: two nonionic surfactants (Unitol L90 and Renex 110 - S), three cosurfactants (butanol, sec-butanol and isoamyl alcohol - C), three aqueous phase (tap water - ADT, acidic solution 6 % HCl, and saline solution - 3.5 % NaCl - AP) and an oil phase (kerosene - OP). From the obtained systems, a common point was chosen belonging to the microemulsion region (25 % [C+S] 5 % OP and AP 70 %), which was characterized at room temperature (25?C) by viscosity (Haake Rheometer Mars), particle diameter (Zeta Plus) and thermal stability. Mixtures with this composition were applied to oil sludge solubilization under agitation at a ratio of 1:4, by varying time and temperature. The efficiencies of solubilization were obtained excluding the solids, which ranged between 73.5 % and 95 %. Thus, two particular systems were selected for use in storage tanks, with efficiencies of oil sludge solubilization over 90 %, which proved the effectiveness of the MES. The factorial design delimited within the domain showed how the MES constituents affect the solubilization of aged oil sludge, as predictive models. The MES A was chosen as the best system, which solubilized a high amount of aged crude oil sludge (~ 151.7 g / L per MES) / No armazenamento de petr?leo a borra ? formada nos fundos de tanques, devido a sua decanta??o, j? que a borra ? composta por grande quantidade de ?leo (fra??es pesadas de petr?leo), ?gua e s?lidos. A borra de petr?leo ? uma mistura complexa, viscosa e considerada um res?duo perigoso, tornando-se necess?rio desenvolver tecnologias e m?todos que facilitem a limpeza, a extra??o do ?leo e a aplica??o na ind?stria. Portanto, neste trabalho objetivou-se determinar a composi??o da borra de petr?leo, obter e caracterizar sistemas microemulsionados (SME), e estudar as suas aplica??es no tratamento da borra. Neste contexto, utilizou-se a extra??o Soxhlet da borra de petr?leo bruta e da borra envelhecida, permitindo quantificar o teor de ?leo (43,9 % e 84,7 % - 13 ?API), de ?gua (38,7 % e 9,15 %) e de s?lidos (17,3 % e 6,15 %), respectivamente. Os res?duos foram caracterizados atrav?s das t?cnicas de fluoresc?ncia de raios X (FRX), de difra??o de raios X (DRX) e Infravermelho de transmiss?o (IFT). O FRX determinou a presen?a de ferro e enxofre em maiores propor??es, comprovando-se pelo DRX a presen?a dos seguintes minerais: Pirita (FeS2), Pirrotita (FeS) e Magnetita (Fe3O4). O IFT mostrou a presen?a de fra??es pesadas de petr?leo. Em paralelo foram obtidos doze SME, combinando os seguintes constituintes: dois tensoativos n?o i?nicos (Unitol L90 e Renex NP110 - T), tr?s cotensoativos (butanol, sec-butanol e ?lcool isoam?lico - C), tr?s fases aquosas (?gua de torneira - ADT, solu??o ?cida HCl 6 % e solu??o salina NaCl 3,5 % - Fa) e uma fase ?leo (querosene - Fo). A partir da obten??o destes sistemas, foi escolhido um ponto em comum na regi?o de microemuls?o (25 % [C+T], 5 % Fo e 70 % Fa), os quais foram caracterizados, a temperatura ambiente (25?C), atrav?s da viscosidade (Re?metro de Haake Mars), di?metro de part?culas (Zeta Plus) e estabilidade t?rmica. Misturas com essa composi??o foram aplicadas na solubiliza??o da borra do petr?leo, sob agita??o, na propor??o de 1:4, variando tempo e temperatura. As efici?ncias de solubiliza??o foram obtidas desconsiderando o teor de s?lidos, situado em uma faixa de 73,5 % a 95 %. Assim, escolheram-se dois sistemas como destaque para aplica??o em tanques de armazenamento, com efici?ncias de solubiliza??o da borra de petr?leo acima de 90 %, comprovando-se assim a efic?cia do SME. Os planejamentos experimentais fatoriais delimitaram dentro do dom?nio a influ?ncia de constituintes dos SME na solubiliza??o da borra de petr?leo envelhecida, com modelos preditivos. O SME A foi escolhido como o melhor sistema, que solubilizou elevada concentra??o de borra de petr?leo bruta envelhecida (~151,7 g/L por SME)
2

Sistema microemulsionado: caracteriza??o e aplica??o na ind?stria de petr?leo

Silva, Guymmann Clay da 12 August 2011 (has links)
Made available in DSpace on 2014-12-17T15:42:14Z (GMT). No. of bitstreams: 1 GuymmannCS_DISSERT-.pdf: 2904070 bytes, checksum: 4cd1c00978977c422c79766db70f2678 (MD5) Previous issue date: 2011-08-12 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Alkyl polyethoxylates are surfactants widely used in vastly different fields, from oil exploitation to pharmaceutical applications. One of the most interesting characteristics of these surfactants is their ability to form micellar systems with specific geometry, the so-called wormlike micelle. In this work, microemulsions with three distinct compositions (C/T = 40 %, 30 % and 25 %) was used with contain UNITOL / butanol / water / xylene, cosurfactant / surfactante (C/S) ratio equal to 0,5. The microemulsion was characterized by dynamic light scattering (DLS), capillary viscometry, torque rheometry and surface tensiometry experiments carried out with systems based on xylene, water, butanol (cosurfactant) and nonaethyleneglycolmonododecyl ether (surfactant), with fixed surfactant:cosurfactant:oil composition (with and without oil phase) and varying the overall concentration of the microemulsion. The results showed that a transition from wormlike micelles to nanodrops was characterized by maximum relative viscosity (depending on how relative viscosity was defined), which was connected to maximum effective diameter, determined by DLS. Surface tension suggested that adsorption at the air water interface had a Langmuir character and that the limiting value of the surfactant surface excess was independent of the presence of cosurfactant and xylene. The results of the solubilization of oil sludge and oil recovery with the microemulsion: C/S = 40%, 30% and 25% proved to be quite effective in solubilization of oil sludge, with the percentage of solubilization (%solubilization) as high as 92.37% and enhanced oil recovery rates up to 90.22% for the point with the highest concentration of active material (surfactant), that is, 40%. / Os tensoativos alquil-polietoxilados s?o amplamente utilizados em diferentes campos, desde a explota??o de petr?leo at? aplica??es na ind?stria farmac?utica. Uma das caracter?sticas mais interessantes destes tensoativos ? a sua capacidade de formar sistemas micelares que apresentam uma geometria micelar espec?fica, a chamada micela wormlike, tipo verme . Neste trabalho, foram utilizados tr?s pontos de microemuls?o: C/T = 40 %, C/T = 30 % e C/T = 25 % num sistema contendo UNITOL/xileno/butanol/?gua. Esses pontos de microemuls?o foram caracterizados por espalhamento de luz din?mico (DLS), viscosimetria capilar, reometria de torque e tens?o superficial com composi??es de tensoativo, cotensoativo e ?leo fixo - 5 % (com e sem fase ?leo) e variando a concentra??o total dos pontos de microemuls?o. Os resultados mostraram que a transi??o da geometria de micela wormlike para nanogotas poderia ser caracterizada por um m?ximo na viscosidade relativa (dependendo de como a viscosidade foi definida), que foi vinculado a um m?ximo de di?metro efetivo, determinada por DLS. A tens?o superficial sugeriu que a adsor??o na interface ?gua/ar tinha um car?ter de Langmuir, o limite de excesso da superf?cie do tensoativo ? independente da presen?a de cotensoativo e do xileno, e que o valor limite do excesso superficial foi independente da presen?a de cotensoativo e xileno. Os resultados da solubiliza??o da borra de petr?leo e da recupera??o avan?ada de petr?leo com os pontos de microemuls?o C/T = 40 %, C/T = 30 % e C/T = 25 %, se mostraram bastante eficaz com solubiliza??o da borra de petr?leo, com porcentagem de solubiliza??o (% solubiliza??o) at? 92,37 %, e recupera??o avan?ada de petr?leo de at? 90,22 % para o ponto que apresenta maior concentra??o de mat?ria ativa (tensoativo), ou seja, C/T = 40 %.

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