Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-10-11T22:42:30Z No. of bitstreams: 1 PedroTupaPandavaAum_TESE.pdf: 7374843 bytes, checksum: da0bd8befae6b9c55d40316b4a0ba58d (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-10-17T23:38:00Z (GMT) No. of bitstreams: 1 PedroTupaPandavaAum_TESE.pdf: 7374843 bytes, checksum: da0bd8befae6b9c55d40316b4a0ba58d (MD5) / Made available in DSpace on 2016-10-17T23:38:00Z (GMT). No. of bitstreams: 1 PedroTupaPandavaAum_TESE.pdf: 7374843 bytes, checksum: da0bd8befae6b9c55d40316b4a0ba58d (MD5) Previous issue date: 2016-03-22 / Um dos desafios na acidifica??o de po?os em forma??es carbon?ticas ? o controle da rea??o de dissolu??o do carbonato de c?lcio. Devido a elevada taxa de rea??o entre o ?cido clor?drico (HCl) e a forma??o, o HCl ? todo consumido na regi?o da forma??o pr?xima ao po?o de maneira que as zonas mais profundas n?o s?o alcan?adas e as regi?es de dano podem n?o ser ultrapassadas. Diversos sistemas foram desenvolvidos para retardar a rea??o de dissolu??o, incluindo a utiliza??o de ?cidos org?nicos, sistemas viscosos e emulsionados. Contudo, poucos estudos reportam a utiliza??o de sistemas microemulsionados como sistemas retardados. Neste trabalho foram estudados sistemas microemulsionados ?cidos do tipo ?leo em ?gua para aplica??o em acidifica??o de carbonatos e limpeza de po?o. O trabalho foi dividido em duas etapas principais, sendo elas: a obten??o e caracteriza??o dos sistemas; e a avalia??o da efici?ncia realizando experimentos de inje??o em plugues de rocha carbon?tica. Para formula??o dos sistemas microemulsionados, dois ?cidos foram utilizados: o ?cido clor?drico (HCl); e o ?cido etilenodiamino tetra-ac?tico (EDTA). O tensoativo utilizado foi o ALK L90 (n?o i?nico), o sec-butanol como co-tensoativo e o xileno como componente org?nico. Foram obtidos sistemas microemulsionados ?cidos com HCl e com EDTA. Os resultados mostraram que a adi??o de ?cidos em determinadas condi??es promove a transi??o de fases dos sistemas de microemuls?o. Os ensaios de inje??o mostraram que os sistemas microemulsionados ?cidos propostos foram eficientes em estimular os plugues de forma??o carbon?tica, alcan?ando incrementos na permeabilidade entre 10-30%, sem apresentar dissolu??o na face e formando wormholes. / One of the challenges in acidification of wells in carbonate formations is controlling the dissolution reaction of calcium carbonate. Due to the high rate of reaction between hydrochloric acid (HCl) and the rock formation, the HCl is all consumed close to the wellbore region. In this way, the deeper areas are not reached and the damage regions may not be exceeded. Several systems have been developed to retard the dissolution reaction, including the use of organic acids, viscous emulsion systems, and the use of chelating agents. However, few studies have reported the use of microemulsion systems as retarded acid systems. In this work, oil in water acid microemulsions are studied for use in carbonate acidizing. The work was divided into two main stages. The first stage was the obtaining and the characterizing of the systems and the second one was the efficiency evaluation by performing injection experiments in carbonate cores. Two microemulsion systems were obtained, one using the hydrochloric acid (HCl) and the second using the ethylenediaminetetraacetic acid (EDTA), a chelating agent. The surfactant used was the ALK-L90 (non-ionic), sec-butanol was used as a co-surfactant, and xylene as the organic component. The results showed that the addition of the HCl or chelating agent promotes the transition of the phase of microemulsion system. Wettability studies showed that the microemulsion systems obtained have a greater power of interaction with the carbonate than the aqueous solutions and also the microemulsion systems without addition of HCl or EDTA. The coreflood experiments showed that the microemulsion systems obtained were effective in stimulating the carbonate cores, achieving increases in permeability up to 86% without showing core face dissolution. The HCl and EDTA corrosiveness in microemulsion media was 80% less than in the aqueous solution. The microemulsion systems obtained can be a promising candidate to use as alternative fluids to carbonate stimulation.

Made available in DSpace on 2014-12-17T14:08:46Z (GMT). No. of bitstreams: 1 PedroTPA_DISSERT.pdf: 2026522 bytes, checksum: 77beea38c42704a86dbc6a2648061f42 (MD5) Previous issue date: 2011-07-04 / Stimulation operations have with main objective restore or improve the productivity or injectivity rate in wells. Acidizing is one of the most important operations of well stimulation, consist in inject acid solutions in the formation under fracture formation pressure. Acidizing have like main purpose remove near wellbore damage, caused by drilling or workover operations, can be use in sandstones and in carbonate formations. A critical step in acidizing operation is the control of acid-formation reaction. The high kinetic rate of this reaction, promotes the consumed of the acid in region near well, causing that the acid treatment not achive the desired distance. In this way, the damage zone can not be bypassed. The main objective of this work was obtain stable systems resistant to the different conditions found in field application, evaluate the kinetic of calcite dissolution in microemulsion systems and simulate the injection of this systems by performing experiments in plugs. The systems were obtained from two non ionic surfactants, Unitol L90 and Renex 110, with sec-butanol and n-butanol like cosurfactants. The oily component of the microemlsion was xilene and kerosene. The acqueous component was a solution of HCl 15-26,1%. The results shown that the microemulsion systems obtained were stable to temperature until 100?C, high calcium concentrations, salinity until 35000 ppm and HCl concentrations until 25%. The time for calcite dissolution in microemulsion media was 14 times slower than in aqueous HCl 15%. The simulation in plugs showed that microemulsion systems promote a distributed flux and promoted longer channels. The permeability enhancement was between 177 - 890%. The results showed that the microemulsion systems obtained have potential to be applied in matrix acidizing / As opera??es de estimula??o s?o opera??es realizadas com a finalidade de restaurar ou melhorar o ?ndice de produ??o ou inje??o dos po?os. Dentre as opera??es de estimula??o, destaca-se a opera??o de acidifica??o, que consiste na inje??o de solu??es ?cidas na forma??o, com press?o abaixo da press?o de fratura da forma??o. A acidifica??o tem como principal objetivo remover danos causados nas etapas de perfura??o e/ou workover, podendo ser realizada tanto em arenitos quanto em carbonatos. Um dos pontos mais cr?ticos da opera??o de acidifica??o ? o controle da rea??o ?cido-rocha, pois a elevada velocidade da rea??o faz com que o ?cido seja todo consumido na regi?o pr?xima ao po?o, fazendo com que o tratamento ?cido n?o atinja a dist?ncia desejada. Dessa maneira, as regi?es com dano podem n?o ser ultrapassadas. Este trabalho teve como objetivo obter sistemas microemulsionados est?veis ?s diferentes condi??es encontradas no campo de aplica??o, avaliar a cin?tica de dissolu??o da calcita nesses sistemas, bem como, simular a inje??o desses sistemas realizando ensaios em plugues. Utilizaram-se sistemas microemulsionados obtidos a partir dos tensoativos Renex 110, Unitol L90 e o OMS (?leo de mamona saponificado). Foram utilizandos o sec-butanol e o n-butanol como cotensoativos. Como componentes org?nicos foram utilizados o xileno e o querosene e como componente aquoso foram utilizadas solu??es de HCl variando-se a concentra??o de 15-26,1%. Os resultados mostraram que os sistemas microemulsionados foram est?veis ? temperaturas de at? 100?C, ? concentra??es elevadas de c?lcio, ? salinidade de at? 35000 ppm e a concentra??es de HCl de at? 25%. A cin?tica de dissolu??o da calcita, ao utilizar os sistemas microemulsionados ?cidos, foi at? 14 vezes mais lenta quando comparada com a solu??o de HCl 15%. Os resultados da inje??o dos sistemas ?cidos mostraram que as microemuls?es favorecem um fluxo mais distribu?do com rela??o ao HCl 15%, bem como, formam canais mais longos, promovendo incrementos na permeabilidade dos plugues de 177 - 890%. Os resultados mostraram que os sistemas microemulsionados possuem potencial para aplica??o em opera??es de acidifica??o de po?os