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dc.contributor.advisorTutuncu, Azra
dc.contributor.authorBùi, Bình Thanh
dc.contributor.committeememberMustoe, Graham G. W.
dc.contributor.committeememberDavis, Thomas L. (Thomas Leonard), 1947-
dc.contributor.committeememberBatzle, Michael L.
dc.contributor.committeememberKazemi, Hossein
dc.contributor.committeememberOzkan, E.
dc.date.accessioned2016-06-08T21:15:03Z
dc.date.available2016-06-08T21:15:03Z
dc.date.issued2016
dc.descriptionIncludes bibliographical references.
dc.description2016 Spring.
dc.description.abstractAbstract Because most of the hydrocarbon remains trapped in the reservoir, recovery factors for tight oil and shale oil are very low. Recovery factors for these formations typically range from 3 to 7%. Since shale matrix has very low permeability, conventional reservoir simulators often overestimate the mass exchange between shale matrix and fractures. To evaluate the potential of water injection for improving oil recovery, the mass transport in the reservoir at different scales should be modeled properly. These issues have motivated us to conduct this research study to evaluate the potential of water injection enhanced oil recovery in liquid-rich unconventional reservoirs accounting for the effects of salt concentration, fluid type, shale swelling, and wettability alteration. There are several mechanisms for the imbibition of water into the rock matrix. In pore scale modeling, it was shown in this research that the interfacial tension-induced transport is one of the key mechanisms contributing to the transport of oil trapped in the pores. The change in the interfacial tension and the contact angle results in wettability alteration and can be interpreted as one of the key factors for imbibition of water into the rock matrix, especially in oil-wetted matrix blocks as observed in laboratory experiments. The amount of oil recovery varies for various ion types, indicating an effect of ion type on the oil recovery. This original pore scale modeling study helps us to evaluate the contribution of interfacial tension-induced transport on the imbibition of water into pores. However, upscaling from pore scale to a larger scale requires further studies for a true representation of the reservoir conditions. Hence, while a new pore scale model was introduced in our research study, it is not fully incorporated in the matrix block and reservoir scale models presented in this study. In a matrix block scale model, a phenomenological model for mass exchange between the rock matrix and the fractures was formulated to compute the mass transfer used in reservoir scale model. This mass transport model was validated using experimental data. A shale swelling model was also derived to account for the swelling effect on the matrix and fracture permeability and porosity by solving the coupled geomechanics and mass transport models. The coupled fluid flow and geomechanics model was solved for every matrix block within the reservoir scale model to evaluate the overall effect of salt concentration, shale swelling, and wettability alteration on oil recovery. The matrix block scale simulation results indicate that osmosis is an important force imbibing water into low permeability rock matrix and enhancing the effectiveness of low salinity waterflooding on oil recovery. The imbibition of water into oil-wetted shale matrix is mainly driven by the osmotic transport and wettability alteration. The contribution of osmotic transport continues for a long period of time and contributes to oil production if the membrane efficiency is high and the matrix block size is small. However, the low membrane efficiency of the shale formations, typically less than 10%, considerably reduces the contribution of osmosis on oil recovery. The effect of fluid type on the oil recovery depends on the membrane efficiency and the diffusion coefficient of the ion. Higher membrane efficiency and lower diffusion coefficient of dissolved ions increase the contribution of osmosis on the oil recovery from shale matrix. Matrix swelling decreases matrix and fracture porosity, forcing the fluid out of the rock matrix and maintaining the pressure in fracture. However, matrix swelling significantly reduces the permeability of the matrix and fractures, reducing oil recovery. Therefore, water injection is not recommended for formations with high swelling potential. Further research on wettability alteration and membrane efficiency variation is recommended for enhanced oil recovery operation in liquid-rich unconventional reservoirs.
dc.format.mediumborn digital
dc.format.mediumdoctoral dissertations
dc.identifierT 8043
dc.identifier.urihttp://hdl.handle.net/11124/170232
dc.languageEnglish
dc.publisherColorado School of Mines. Arthur Lakes Library
dc.relation.ispartof2016 - Mines Theses & Dissertations
dc.rightsCopyright of the original work is retained by the author.
dc.subjectenhanced oil recovery
dc.subjectinterfacial tension-induced transport
dc.subjectmass transport
dc.subjectmulti-physics and multi-scale reservoir modeling
dc.subjectpore scale modeling
dc.subjectunconventional reservoirs
dc.titleMulti-physics model for enhanced oil recovery in liquid-rich unconventional reservoirs, A
dc.typeText
thesis.degree.disciplinePetroleum Engineering
thesis.degree.grantorColorado School of Mines
thesis.degree.levelDoctoral
thesis.degree.nameDoctor of Philosophy (Ph.D.)


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