Pore-Scale Monitoring of Wettability Alteration by Silica Nanoparticles During Polymer Flooding to Heavy Oil in a Five-Spot Glass Micromodel

Abstract

It is well known that the oil recovery is affected by wettability of porous medium; however, the role of nanoparticles on wettability alteration of medium surfaces has remained a topic of debate in the literature. Furthermore, there is a little information of the way dispersed silica nanoparticles affect the oil recovery efficiency during polymer flooding, especially, when heavy oil is used. In this study, a series of injection experiments were performed in a five-spot glass micromodel after saturation with the heavy oil. Polyacrylamide solution and dispersed silica nanoparticles in polyacrylamide (DSNP) solution were used as injected fluids. The oil recovery as well as fluid distribution in the pores and throats was measured with analysis of continuously provided pictures during the experiments. Sessile drop method was used for measuring the contact angles of the glass surface at different states of wettability after coating by heavy oil, distilled water, dispersed silica nanoparticles in water (DSNW), polyacrylamide solution, and DSNP solution. The results showed that the silica nanoparticles caused enhanced oil recovery during polymer flooding by a factor of 10%. The distribution of DSNP solution during flooding tests in pores and throats showed strong water-wetting of the medium after flooding with this solution. The results of sessile drop experiments showed that coating with heavy oil, could make an oil-wet surface. Coating with distilled water and polymer solution could partially alter the wettability of surface to water-wet and coating with DSNW and DSNP could make a strongly water-wet surface.

Wettability alteration of oil-wet carbonate by silica nanofluid

“…Furthermore, it is highly desirable to change oil-wet surfaces more water-wet in carbon geo-sequestration projects to increase storage capacities and de-risk containment security [30,73]. Despite the vital importance for limestone reservoirs, previous studies focused on sandstone formations [21,25,26,28,41], and only limited information is available for carbonate reservoirs [40,42].…”

“…However, the efficiency of such formulations is a complex function of several factors, including the size and type of nanoparticles, nanofluid preparation and stability, the nature of the porous medium, thermo-physical and geological conditions and dwell time in the reservoir [39,40]. Despite the vital importance for limestone reservoirs globally, previous studies focused on sandstone formations [21,25,26,28,41], and only limited information is available for carbonate reservoirs: Roustaei and Bagherzadeh [42] conducted coreflood tests and they demonstrated that nanofluid-EOR can increase oil production by 9-17% depending on ageing time, and Zhang et al [40] have investigated the adsorption behaviour of silica nanoparticles on calcite powder.…”

Application of Nanoparticles in Enhanced Oil Recovery: A Critical Review of Recent Progress

“…In order to observe the microscopic behavior of polymer solutions with NPs in porous media, Maghzi et al [119,122] studied the performance of silica NPs in polyacrylamide solution in a five-spot glass micromodel saturated with heavy oil. They observed that the silica NPs caused an increase in oil recovery of polymer flooding by a factor of 10%, and strong water-wetting of the medium after flooding.…”

Experimental investigation of SiO2 nanoparticles on enhanced oil recovery of carbonate reservoirs

“…Application of these Nanoparticles for enhancing oil recovery in water-wet sandstone systems is well documented in the literature (Ju et al 2002(Ju et al , 2006Ju and Fan 2009;Onyekonwu and Ologo 2010;Wang et al 2010). However, from the view of the literature in this field, only few papers address the application of these Nanoparticles in wettability alteration of carbonate systems (Maghzi et al 2011). In previous studies, the effect of Nanoparticles on oil-water interfacial tension and/or as an additive in waterflooding has not been investigated.…”