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Wettability Alteration and its Effect on Oil Recovery by using Colloidal Nano-Silica in Oil Reservoirs
, M.Sc. Thesis Sharif University of Technology ; Ayatollahi, Shahabodin (Supervisor) ; Goodarznia, Iraj (Supervisor) ; Badakhshan, Amir (Co-Supervisor)
Abstract
As many oil fields are reaching their final stage of production, new technologies are required in order to maintain production and increase recovery of hydrocarbons. Among these techniques of enhanced oil recovery (EOR), chemical injection method focuses on increasing the effectiveness of waterflooding. Due to the relatively high costs and considerable adsorption on the rock formations, this method is no longer used. In Recent years nanofluids (nanoparticles dispersed in brine) have been used as a cheap, efficient and environmentally friendly alternative more than any other chemicals. It has been stated that the Smart Water method and enhanced oil recovery by SiO2 nanoparticles are effective...
Wettability alteration and oil recovery by spontaneous imbibition of low salinity brine into carbonates: Impact of Mg2+, SO4 2− and cationic surfactant
, Article Journal of Petroleum Science and Engineering ; Volume 147 , 2016 , Pages 560-569 ; 09204105 (ISSN) ; Al-Maamari, R. S ; Ayatollahi, S ; Mehranbod, N ; Sharif University of Technology
Elsevier B.V
2016
Abstract
A large amount of the discovered oil reserves are reserved in carbonate formations, which are mostly naturally fractured oil-wet. Wettability alteration towards more water-wet state reduces the capillary barrier, hence improving the oil recovery efficiency in such reservoirs. In this study, wettability alteration towards favorable wetting state was investigated by combining modified low salinity brine with surfactant during water flooding. The diluted brine was modified by increasing the concentration of Mg2+ and SO4 2−, individually as well as both ions in combination. Different brine formulations were tested experimentally through the observations of contact angle measurements and...
Effect of brine salinity and hydrolyzed polyacrylamide concentration on the Oil/Brine and Brine/Rock Interactions: Implications on enhanced oil recovery by hybrid low salinity polymer flooding in sandstones
, Article Fuel ; Volume 324 , 2022 ; 00162361 (ISSN) ; Fatemi, M ; Biniaz Delijani, E ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
The main idea behind the application of Low salinity polymer flooding (LSPF) enhanced oil recovery (EOR) method is that diluted brine improves the oil recovery by wettability alteration from oil-wet (OW) towards water-wet (WW) condition, while polymer enhances the mobility of the displacing phase. However the possible effect of polymer on the fluid/fluid and fluid/rock interactions are not investigated systematically in the literature. The main objective of the present reserach is to examine the possible effect of hybrid application of low-salinity and polymer on the brine/rock and brine/oil interfaces properties. Formation water (FW) and sea water (SW) and its two different dilutions, i.e....
Pore scale visualization of fluid-fluid and rock-fluid interactions during low-salinity waterflooding in carbonate and sandstone representing micromodels
, Article Journal of Petroleum Science and Engineering ; 2020 ; Fatemi, M ; Masihi, M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Low Salinity Waterflooding (LSWF) has become a popular tertiary injection EOR method recently. Both fluid-fluid and fluid-rock interactions are suggested as the contributing mechanisms on the effectiveness of LSWF. Considering the contradictory remarks in the literature, the dominating mechanisms and necessary conditions for Low Salinity Effect (LSE) varies for different crude oil-brine-rock (CBR) systems. The aim of the present study is to investigate LSE for an oil field in the Middle East that is composed of separate sandstone and limestone layers. Contact angles and Interfacial Tension (IFT) are measured to have more insight on the CBR under investigation. Visual experiments were...
Determining water-oil relative permeability and capillary pressure from steady-state coreflood tests
, Article Journal of Petroleum Science and Engineering ; Volume 205 , 2021 ; 09204105 (ISSN) ; Hemmati, N ; Behr, A ; Genolet, L ; Mahani, H ; Zeinijahromi, A ; Bedrikovetsky, P ; Sharif University of Technology
Elsevier B.V
2021
Abstract
This study aims at the simultaneous determination of relative permeability and capillary pressure from steady-state corefloods. Besides using the measurements of pressure-drop across the core and average saturation under steady-state conditions, we use the transient data between the sequential steady states. The inverse algorithm is based on four type curves “stabilizsation period versus water-cut” revealed by asymptotic analysis of the transient solution near end-point saturations, and on the exponential shape of transition data histories observed by direct numerical runs. The transition measurements are approximated in the stabilisation periods by the type curves using non-linear...
Experimental investigation on the dominating fluid-fluid and rock-fluid interactions during low salinity water flooding in water-wet and oil-wet calcites
, Article Journal of Petroleum Science and Engineering ; Volume 204 , 2021 ; 09204105 (ISSN) ; Fatemi, M ; Ayatollahi, S ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Low salinity water flooding (LSWF) has the potential to enhance the oil recovery by affecting the fluid-fluid and rock-fluid interactions. Therefore, a systematic investigation on the effect of initial wetting state (water-wet or oil-wet) of pure calcite is conducted to study the importance of these interactions on the effectiveness of LSWF. In the case of initially water-wet cores, more oil recovery efficiency is observed for more saline water cases. To shed light on the possible involved mechanisms, dynamic IFT, dynamic contact angle (CA), oil/brine and rock/brine surfaces zeta potentials, and effluent pH are measured. It is shown that the short-term effect of IFT reduction and long-term...
Pore scale visualization of fluid-fluid and rock-fluid interactions during low-salinity waterflooding in carbonate and sandstone representing micromodels
, Article Journal of Petroleum Science and Engineering ; Volume 198 , 2021 ; 09204105 (ISSN) ; Fatemi, M ; Masihi, M ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Low Salinity Waterflooding (LSWF) has become a popular tertiary injection EOR method recently. Both fluid-fluid and fluid-rock interactions are suggested as the contributing mechanisms on the effectiveness of LSWF. Considering the contradictory remarks in the literature, the dominating mechanisms and necessary conditions for Low Salinity Effect (LSE) varies for different crude oil-brine-rock (CBR) systems. The aim of the present study is to investigate LSE for an oil field in the Middle East that is composed of separate sandstone and limestone layers. Contact angles and Interfacial Tension (IFT) are measured to have more insight on the CBR under investigation. Visual experiments were...
Mechanistic study of wettability alteration of oil-wet calcite: The effect of magnesium ions in the presence and absence of cationic surfactant
, Article Colloids and Surfaces A: Physicochemical and Engineering Aspects ; Volume 482 , October , 2015 , Pages 403-415 ; 09277757 (ISSN) ; Al Maamari, R. S ; Ayatollahi, S ; Mehranbod, N ; Sharif University of Technology
Elsevier
2015
Abstract
Over 60% of the world's discovered oil reserves are held in carbonate reservoirs, which are mostly naturally fractured. Conventional water flooding results in low oil recovery efficiency in these reservoirs as most of them are oil-wet. On account of negative capillary forces, injected brine cannot penetrate simply into an oil-wet matrix of fractured formations to force the oil out. Wettability alteration of the rock surface to preferentially more water-wet state has been extensively studied using both smart water and surfactants separately. This study aims to study the effects of Mg2+ as one of the most important wettability influencing ions on the wetting properties of oil-wet carbonate...