Browsing by Author "Dejam, Morteza"

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    Investigation of the Interaction between Nanoparticles, Asphaltenes, and Silica Surfaces for Inhibition and Remediation of Formation Damage
    (2021-07-19) Montoya, Leidy Tatiana; Nassar, Nashaat N.; Chen, Shengnan (Nancy); Hassanzadeh, Hassan; Moore, Robert Gordon; Khoshnazar, Rahil; Dejam, Morteza
    World population growth, increment in industrialization and motorization of the world, increment in technical development and living standards are some factors that keep contributing to the increasing of the global energy demand. Therefore, it is necessary to find alternative sources to meet these demands. Considering renewable and non-renewable energies, there is still an interest in enhancing the oil and gas recovery, because its reserves are considerable in terms of the energy supply. Nevertheless, there are several challenges facing the oil production related with asphaltenes, and it requires a knowledge on the deposition mechanism of this fraction of oil and the factors influencing it, since they are important in many parts of the production processes, and refinery catalyst deactivation, causing significant production losses. Accordingly, appropriate mitigation techniques, for surfaces exposed to asphaltenes or operating conditions, can be identified. It has been demonstrated that the use of nanoparticles may improve the mobility of oil. This is because nanoparticles may enhance wettability alteration or disaggregation of asphaltene aggregates. Accordingly, this study will help to understand the interactions between asphaltenes and nanoparticles, at the beginning using computational modeling and model molecules for resins and asphaltenes. It is important to consider that asphaltenes are not the only component in the oil and the adsorbent affinity is affected for it. Then, naturally derived silicate-based nanoparticles were used to investigate their performance on wettability alteration and what is the mechanism involved in continuous flow over pre-adsorbed/deposited asphaltene SiO2 sensors; this was achieved using a QCM-D, contact angle measurements and AFM images. The results showed that depending on the asphaltenes aggregation stage, the nanoparticles interact differently with them. Finally, basic silicate-based nanofluids were tested at reservoir conditions. The main results indicated that low salinity was the most promising formulation for inhibiting/remediating formation damage caused by asphaltene precipitation/deposition. Relative permeability curves showed a shift to right after the injection of nanoparticles, confirming the role of nanoparticles on wettability alteration. Oil recovery factor was also increased when using nanoparticles to inhibit/remediate the damage. Therefore, silicate-based nanoparticles are good candidates to use as treatment for asphaltene formation damage.
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    ItemOpen Access
    Shear Dispersion in Double-Porosity Systems
    (2016) Dejam, Morteza; Hassanzadeh, Hassan; Chen, Zhangxing (John); Maini, Brij; Hejazi, Hossein; Achari, Gopal; Mendoza, Carl
    In this study, shear dispersion in double-porosity systems has been investigated. The major focus of this study is determination of dispersion coefficients through development of mathematical models for solute transport in a variety of coupled double-porosity systems by imposing an accurate boundary condition at the interface between a porous medium and a conduit. Theoretical determination of shear dispersions presented in this thesis can be categorized as shear dispersions in: i) a fracture with porous walls, ii) a capillary tube with a porous wall, iii) a rough-walled fracture, iv) a channel with porous walls under the combined effects of pressure-driven and electro-osmotic flows, and v) a capillary tube with a porous wall under the combined effects of pressure-driven and electro-osmotic flows. For determination of the dispersion coefficients, first, a two-dimensional coupled solute transport model is introduced where the interaction between a porous medium and a conduit is handled by imposing the continuity of concentrations and mass fluxes at the interface instead of applying a source/sink term in the governing equations. Second, the Reynolds decomposition technique is used to develop a reduced one-dimensional model for advective-dispersive transport in a conduit with equivalent transport coefficients such as the dispersion coefficient and the effective advection term. Third, the Laplace transform method combined with the Fourier inversion technique is applied to solve the one-dimensional problems and obtain the concentrations in the porous medium and the conduit as well as mass storage in the porous medium. The developed models with the coupled dispersion coefficients serve as new tools to characterize solute transport in double-porosity systems and also can be used for implementation in the existing simulators for better predictions. The developed models for the shear dispersion find applications in solute transport through fractured rocks, fluid flow in hydraulically fractured shale reservoirs, separation of emulsions in microchannel-membrane systems, and electrically assisted chemical species transport in porous microfluidic networks.