Enhanced Oil Recovery Mechanisms Research Articles

Investigation of carbon-based nanofluid imbibition processes in low-permeability reservoirs using nuclear magnetic resonance

Spontaneous imbibition has been demonstrated to be an important approach to enhance the oil recovery of unconventional reservoirs after hydraulic fracturing. Adding chemical agents to modulate the properties of the oil-water and oil-rock interfaces is a common method to enhance imbibition. Carbon-based nanofluid showed excellent ability to reduce interfacial tension and alter wettability due to their distinct surface properties and ultra-small particle size. However, there are few systemic studies on the imbibition process of carbon-based nanofluid and the unclear mechanism of the enhanced oil recovery (EOR) restricts their oilfield application. In this study, the carbon-based nanofluid was prepared by dispersing carbon nitride quantum dots (CNQDs) of 2.34 ± 0.34nm synthesized by citric acid and urea in deionized water. The spontaneous imbibition process of nanofluids was monitored by nuclear magnetic resonance (NMR) technology. The T2 relaxation distribution results suggested that the oil recovery of CNQDS nanofluid by spontaneous imbibition was 24.6%, which was 5% higher than that of nano-SiO2 nanofluid. Moreover, the variations of oil saturation profiles analyzed based on NMR data indicated that the maximum imbibition distance of the carbon-based nanofluid was about 20.34mm which is also larger than that of the nano-SiO2 nanofluid of 16.02mm. The oil saturation variations of saturated oil cores imbibed in carbon-based nanofluid was also significantly improved compared with nano-SiO2 nanofluid. This finding was attributed to the fact that compared with nano-SiO2 nanofluid, the CNQDs nanofluid can not only promote the fluid to enter deeper matrix, but also effectively reduce the residual oil saturation in the area that the nanofluid accesses to. The interfacial tension and contact angle measurements were conducted to reveal the underlying EOR mechanisms of CNQDs nanofluid. This study provides vital insights into the prospective application of carbon-based nanofluid in low-permeability reservoirs.

Decoding the dynamic of CH4 and CO2 displacement for enhanced condensate oil recovery

Gas-condensate reservoirs have attracted wide attention owing to substantial gas and high-quality condensate oil. However, the limited research makes the enhanced oil recovery mechanism through gas injection in condensate reservoirs remains poorly understood. This study explores the intricate molecular interactions of gas displacement in condensate oil recovery. The results underscore that CH4 proves more effective in extracting light components, while CO2 excels in extracting both light and heavy components. Microscopic analysis reveals unique displacement mechanisms, with CH4 displacing light components and forming clusters that concentrate in the center of the pore. In contrast, CO2 induces continuous dispersion and expansion of condensate oil components, thereby extracting more oil from the pore. Additionally, the study emphasizes the influence of pore geometry on condensate oil recovery. These insights provide valuable guidance for optimizing strategies for the gas-driven recovery of condensate oil.

Degradation and enhanced oil recovery potential of Alcanivorax borkumensis through production of bio-enzyme and bio-surfactant

Microbial enhanced oil recovery (EOR) has become the focus of oilfield research due to its low cost, environmental friendliness and sustainability. The degradation and EOR capacity of A. borkumensis through the production of bio-enzyme and bio-surfactant were first investigated in this study. The total protein concentration, acetylcholinesterase, esterase, lipase, alkane hydroxylase activity, surface tension, and emulsification index (EI) were determined at different culture times. The bio-surfactant was identified as glycolipid compound, and the yield was 2.6 ± 0.2 g/L. The nC12 and nC13 of crude oil were completely degraded, and more than 40.0 % of nC14–nC24 was degraded by by A. borkumensis. The results of the microscopic etching model displacement and core flooding experiments showed that emulsification was the main mechanism of EOR. A. borkumensis enhanced the recovery rate by 20.2 %. This study offers novel insights for the development of environmentally friendly and efficient oil fields.

A comprehensive review direct methods to overcome the limitations of gas injection during the EOR process

Among the Enhanced Oil Recovery (EOR) methods, gas-based EOR methods are very popular all over the world. The gas injection has a high ability to increase microscopic sweep efficiency and can increase production efficiency well. However, it should be noted that in addition to all the advantages of these methods, they have disadvantages such as damage due to asphaltene deposition, unfavorable mobility ratio, and reduced efficiency of macroscopic displacement. In this paper, the gas injection process and its challenges were investigated. Then the overcoming methods of these challenges were investigated. To inhibit asphaltene deposition during gas injection, the use of nanoparticles was proposed, which were examined in two categories: liquid-soluble and gas-soluble, and the limitations of each were examined. Various methods were used to overcome the problem of unfavorable mobility ratio and their advantages and disadvantages were discussed. Gas-phase modification has the potential to reduce the challenges and limitations of direct gas injection and significantly increase recovery efficiency. In the first part, the introduction of gas injection and the enhanced oil recovery mechanisms during gas injection were mentioned. In the next part, the challenges of gas injection, which included unfavorable mobility ratio and asphaltene deposition, were investigated. In the third step, gas-phase mobility control methods investigate, emphasizing thickeners, thickening mechanisms, and field applications of mobility control methods. In the last part, to investigate the effect of nanoparticles on asphaltene deposition and reducing the minimum miscible pressure in two main subsets: 1- use of nanoparticles indirectly to prevent asphaltene deposition and reduce surface tension and 2- use of nanoparticles as a direct asphaltene inhibitor and Reduce MMP of the gas phase in crude oil was investigated.

Development and performance evaluation of nonionic surfactant-stabilized nanoemulsion for enhanced oil recovery applications in tight reservoir

Nanoemulsions have garnered great attention as a chemical additive for enhanced oil recovery (EOR) technology worldwide due to their small size and unique physicochemical properties. Herein, this work introduces a novel nonionic surfactant-stabilized nanoemulsion prepared using a low-energy method for EOR projects in the Chang 8 tight reservoir. Spontaneous imbibition experiments were conducted in oil-saturated cores, and secondary imbibition experiments were carried out in water-bearing cores. Additionally, core flooding experiments were performed to study the EOR performance of both nanoemulsion and complex surfactant. Finally, the EOR mechanisms were thoroughly investigated, specifically focusing on oil-washing capacity, reduced interfacial tension, and wettability alteration. The designed nanoemulsion, with droplets averaging 10.5 ± 0.7 nm in synthetic formation brine at ambient temperature, exhibits excellent thermal and long-term stability even under reservoir temperature conditions. The oil recovery efficiency of the nanoemulsion system in oil-saturated cores through spontaneous imbibition was 31.28%, representing a 6.42% improvement over the complex surfactant solution. In the secondary imbibition experiments, the nanoemulsion mobilized 8.53% of the residual oil, compared to 4.11% for the complex surfactant. Core flooding experiments revealed that the nanoemulsion system achieved a total oil recovery of 62.69%, outperforming the complex surfactant system by 8.68% during the chemical flooding stage and 1.82% during the subsequent brine flooding stage. The EOR mechanisms of nanoemulsion in tight reservoirs can be attributed to four aspects: reduction of oil/water interfacial tension, wettability alteration, miscibility with crude oil, and increased sweep volume. The generation of the Marangoni effect and the adsorption and diffusion characteristics are essential differences between the nanoemulsion system and the complex surfactant system. The presented findings in this paper could aid in promoting the large-scale use of nanoemulsions in Chang 8 tight reservoirs.

The Effect of Crude Oil Stripped by Surfactant Action and Fluid Free Motion Characteristics in Porous Medium.

The surfactant solution is crucial in facilitating the spontaneous imbibition process for the recovery of oil in tight reservoirs. Further investigation is required to examine the fluid flow in porous mediums and the process of crude oil stripping by a surfactant solution during spontaneous imbibition. Hence, this study aims to determine the free motion properties of oil and water in porous mediums using the finite-element approach to solve the multiphase flow differential equation, taking into account the capillary pressure. An investigation was conducted to examine the impact of oil viscosity and interfacial tension on the mean liquid flow rate and oil volume fraction. An experimental study was conducted to investigate the impact of surface tension, interfacial tension, and wetting angle on crude-oil-stripping efficiency. The findings indicate that the stripped crude oil migrated through porous mediums as individual oil droplets, exhibiting a degree of stochasticity in its motion. When the interfacial tension is reduced, the average velocity of the fluid in the system decreases. The crude oil exhibited a low viscosity, high flow capacity, and a high average flow rate within the system. Once the concentration of the surfactant solution surpasses a specific threshold, it binds with the oil to create colloidal aggregates, resulting in the formation of micelles and influencing the efficiency of the stripping process. As the temperature rises, the oil-stripping efficiency also increases. Simultaneously, an optimal range of wetting angle, surface tension, and interfacial tension could enhance the effectiveness of removing oil using surfactant solutions. The research results of this paper enrich the enhanced oil recovery mechanism of surfactant and are of great significance to the development of tight reservoirs.

Experimental study of hybrid nanofluid-alternating-CO2 microbubble injection as a novel method for enhancing heavy oil recovery

Water-alternating-CO2 injection (CO2 WAG) is a successful method for enhancing heavy oil recovery and geologic CO2 storage. However, CO2 WAG still has some setbacks, such as water blocking, gravity overriding, and viscous fingering of injected CO2. Therefore, a new method, named hybrid nanofluid-alternating-CO2 microbubble injection, is proposed in this study to improve the effect of CO2 WAG. In this method, the hybrid nanofluid is used to reduce the interfacial tension (IFT) between the heavy oil and brine and alter the sandstone surface wettability. The CO2 microbubbles improve mobility control by minimizing gravity overriding and viscous fingering. In this study, for the first time, hybrid nanofluid and CO2 microbubbles are simultaneously used in WAG processes to enhance heavy oil recovery. Five types of nanoparticles are screened systematically by contact angle and IFT tests to find the best candidate for the hybrid nanofluid in hybrid nanofluid-alternating-CO2 microbubble injection and clarify the enhanced oil recovery mechanisms. Then, oil displacement tests are carried out by using a patented large-scale sandpack to assess the viability of hybrid nanofluid-alternating-CO2 microbubble injection and to analyze the effects of key parameters on the performance of hybrid nanofluid-alternating-CO2 microbubble injection. Our experimental results indicate that Al2O3-SiO2 nanofluid has more influence than TiO2-SiO2 and TiO2-Al2O3 nanofluids on wettability alteration to the water-wet state and IFT reduction. Hybrid nanofluid-alternating-CO2 microbubble injection is a potentially good choice to enhance heavy oil recovery because of the synergistic effect of injecting hybrid nanofluid and CO2 microbubbles. Hybrid nanofluid-alternating-CO2 microbubble injection is suggested to be initiated as early as possible. A smaller slug size is preferred, and the water and gas slugs are suggested to be separately injected from the upper and lower parts of a heavy oil reservoir. The optimum WGR and slug size (1:1 and 0.05PV in this study) should be prudently considered when designing hybrid nanofluid-alternating-CO2 microbubble injection.

The numerical simulation of behaviors of oil-water-emulsion flow in pores by using phase field method

In the emulsion flooding processes, the flow of the emulsion droplets facilitates the oil recovery. However, there is currently limited insight into the microscopic enhanced oil recovery mechanism of emulsion droplets. It is essential to conduct further research to explore the interactions among the emulsion phase, oil phase, and water phase. In this work, the role of emulsion droplets on the mobilization of residual oil was numerically studied by the phase field method. We have studied the relevant mechanism in a single flow region structure, and a porous media. The results show that droplet radius, interfacial tension, and wettability all affect the flow behavior of the emulsion phase. The flow of emulsion results in much more displacement efficiency and sweep efficiency, which helps recover trapped oil in pore corners and the low permeability areas in the porous medium. In contrast to water flooding, the emulsion flooding elevated the oil recovery from 42.8% to 48.5% in the high-permeability region and from 10.9% to 40.4% in the low-permeability region.

Study of the Enhanced Oil Recovery Mechanism and Remaining Oil State of Heavy Oil after Viscosity-Reducer-Assisted CO2 Foam Flooding: 2D Microvisualization Experimental Case

Study of the Enhanced Oil Recovery Mechanism and Remaining Oil State of Heavy Oil after Viscosity-Reducer-Assisted CO₂ Foam Flooding: 2D Microvisualization Experimental Case

Experimental Investigation of Preformed Particle Gel and Alkali-Surfactant-Polymer Composite System for Enhanced Oil Recovery in Heterogeneous Reservoirs

Abstract Heterogeneity is a significant feature of the reservoirs after polymer flooding, resulting in challenges for further enhanced oil recovery (EOR) in heterogeneous reservoirs. In order to further improve oil recovery in the reservoirs after polymer flooding, a novel EOR system (ASP-PPG composite system) was developed using preformed particle gel (PPG) and alkali-surfactant-polymer system (ASP system). We designed an oil saturation monitoring device and a large-scale 3D heterogeneous physical model to evaluate the performance of the system. The performance of the system and the ASP system were tested. Based on the testing results, the fluid migration patterns and enhanced oil recovery mechanisms of the ASP-PPG system in an actual heterogeneous reservoir were investigated using the oil saturation monitoring device and the 3D physical model. Experimental results indicate that the ASP-PPG system has a higher viscosity and better profile control ability than the ASP system. Additionally, the interfacial tension can be maintained at a low level, around 10−3 mN/m. Flooding experiments using the three-dimensional heterogeneous physical model demonstrated the excellent elastic deformation ability of PPG, which can dynamically block the large pores that formed after the polymer flooding and effectively improve the heterogeneity of reservoirs. After injecting the ASP-PPG system, the recovery factor of the model increased by 15.8%. Specifically, the sweep coefficient of high, medium, and low permeability layers increased by 4.36%, 19.6%, and 37.55%, respectively. Moreover, the oil displacement efficiency increased by 7.4%, 14.4%, and 17.9%, respectively. These results highlight the synergistic effect of combining PPG and ASP systems, significantly enhancing heterogeneous reservoir recovery after polymer flooding.

Study on Enhanced Oil Recovery Mechanism of CO2 Miscible Flooding in Heterogeneous Reservoirs under Different Injection Methods.

The mechanism by which oil recovery can be enhanced by different injection methods of CO2 miscible flooding to alleviate the influence of heterogeneous reservoirs was studied to optimize the injection methods, further improving oil recovery. According to the reservoir heterogeneity characteristics of the TI oil formation group in Lunnan Oilfield, a 1 m double-layer long core was designed and prepared for four CO2 miscible displacement experiments with different injection methods. By analyzing the variation in the injection-production parameters, the displacement effects of different injection methods were compared, and the mechanism of enhanced oil recovery (EOR) was summarized. The results indicate the following. ① The displacement efficiency of the different injection methods lies in the following order. Alternate CO2-water injection, continuous CO2 flooding, cyclic CO2 flooding, and alternate CO2-hydrocarbon gas injection. ② The recovery of crude oil via CO2 miscible flooding in heterogeneous reservoirs relies on both convective diffusion and miscible mass transfer. Convective diffusion depends mainly on control of the displacement pressure differential and the plugging of preferential seepage channels in high-permeability areas, while miscible mass transfer depends mainly on the swept range of the convective diffusion and the degree of miscibility between CO2 and crude oil. ③ To improve the recovery efficiency of CO2 miscible flooding in heterogeneous reservoirs, it is necessary to choose an injection method that optimizes these two aspects.

Exploring the Unique Characteristics of High-Pore-Volume Waterflooding and Enhanced Oil Recovery Mechanisms in Offshore Sandstone Reservoirs Using Nuclear Magnetic Resonance Technology

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Molecular dynamics investigation of DME assisted CO2 injection to enhance shale oil recovery in inorganic nanopores

In view of the unsatisfactory improvement effect of pure CO2 injection on the shale oil recovery in microscopic pores, the molecular dynamics method was used to simulate the process of dimethyl ether (DME) assisted CO2 injection in nanopore to recover shale oil. Firstly, cosolvents with different functional groups were selected to assist CO2 injection to compare the enhanced oil recovery (EOR) effect of shale oil. Subsequently, the microscopic mechanism of DME promoting CO2-EOR effect was systematically revealed. Then, the effects of temperature, pressure, DME molar content and shale oil composition on the EOR mechanism of CO2-DME mixture were further studied. Finally, the sensitivity difference of EOR effect to these influencing factors was compared. The research results showed that the EOR effect of DME-assisted CO2 injection (42.96%) is the best, followed by acetone (38.61%), propane (33.38%), ethanol (32.42%) and pure CO2 (22.43%). The microscopic EOR mechanism of DME-assisted CO2 injection includes improving the solubility and competitive adsorption capacity of CO2, as well as reducing oil viscosity and two-phase interfacial tension (IFT). The EOR effect of CO2-DME mixture is the best when the system temperature rises to 100℃, but excessive high temperature has a negative impact on CO2 solubility and intermolecular interaction. The increase of system pressure increases the fluid density, shortens the mass transfer distance, and reduces the IFT, which promotes the solubility, miscibility and competitive adsorption capacity of CO2-DME mixture, thereby continuously improving the shale oil recovery. Although the increase of DME content can improve the competitive adsorption capacity and reduce the IFT, it also reduces the solubility and diffusion capacity. The EOR effect is best when the mole fraction of DME reaches 40%. The increase of the proportion of non-hydrocarbon compounds and heavy hydrocarbon components reduces the solubility, miscibility and competitive adsorption capacity of CO2, and the negative impact of the former is greater than that of the latter. The EOR effect of DME-assisted CO2 injection on shale oil is most affected by pressure, followed by DME mole fraction, temperature, and oil composition.

Investigation of the enhanced oil recovery mechanism of CO2 synergistically with nanofluid in tight glutenite

Investigation of the enhanced oil recovery mechanism of CO2 synergistically with nanofluid in tight glutenite

Nanoparticles for Enhancing Heavy Oil Recovery: Recent Progress, Challenges, and Future Perspectives

Heavy oil is estimated to account for about 70% of the remaining oil reserves and considered as the most promising and readily available oil resource to meet energy demands in the coming decades. However, traditional enhanced oil recovery (EOR) methods for heavy oil face significant challenges, such as high mobility of injected fluids, polymer degradation, surfactant adsorption, significant chemical consumption, considerable energy and water consumption, significant greenhouse gas emissions, high operation costs, and the need for robust facilities. Recently, nanoparticle technology has been launched as a promising alternative technology for heavy oil recovery enhancement due to their unique characteristics of ultrasmall size, large surface area to volume ratio, low costs, and environmental friendliness. This paper presents a comprehensive discussion of the most recent studies about nanoparticle applications for heavy oil recovery and helps researchers gain insights into EOR mechanisms underlying these various applications. Nanoparticle applications for enhancing heavy oil recovery can be summarized into two major categories: nanofluid flooding (i.e., the use of nanoparticles alone) and its hybrids of traditional EOR methods. First, various applications of nanofluid flooding are summarized in terms of incremental oil recovery performance and EOR mechanisms. Second, recent research progress on the hybrids of nanoparticles and traditional EOR methods including thermal, chemical, and gas injection technologies is highlighted. Finally, the challenges and future perspectives for development and applications of nanoparticles for enhancing heavy oil recovery are identified.

Fingering crossover and enhanced oil recovery mechanism of water-alternating-CO2 injection

Combined with strengths of water and CO2 flooding, water-alternating-CO2 (WAG) injection stabilizes displacement front and suppresses viscous fingering. Optimal injection factor and water–CO2 slug ratio (W:G) from both oil field and micromodel were given in previous studies. By analyzing residual oil types and fingering patterns at steady state, enhanced oil recovery (EOR) mechanism of WAG was revealed by comparing with water and CO2 flooding, respectively, regardless of interactions between three phase fluids. However, when oil, water, and CO2 are simultaneously present, the three-phase flow is much more complex, fingering is time-varying, and the patterns are different. Previous knowledge of EOR mechanism of WAG cannot indicate the fingering characteristics in three-phase flows and patterns crossover, resulting in the optimal W:G not being well explained. We simulated a WAG displacement by varying W:G and pressure difference between the inlet and outlet ΔP. EOR mechanism of WAG and optimal W:G were obtained by analyzing time-varying fingerings and patterns crossover in three-phase flows. The results showed that (1) fingering patterns change significantly before and after CO2 injection. At low ΔP (100 < ΔP <1000 kPa), capillary fingering converts to viscous fingering, and at high ΔP (ΔP > 1000 kPa), viscous fingering converts to stable displacement; (2) fingering crossover is discrepant at various W:G, which most easily occurs when W:G = 1:3 and 1.5:3; and (3) EOR capacity of WAG injection is significantly promoted when the fingering pattern changes. These results are helpful to better understand the dynamic displacement mechanism of WAG injection and are important for design and optimization of WAG injection operation.

Experimental Study on the Enhanced Oil Recovery Mechanism of an Ordinary Heavy Oil Field by Polymer Flooding.

It is widely known that in the water flooding development process of ordinary heavy oil, the fingering phenomenon is obvious, there are a lot of unswept areas, and absolutely, the recovery is really very low. In addition, for some shallow and thin ordinary heavy oil reservoirs limited by the geological conditions of the reservoir, the thermal recovery technology also has serious heat loss and high development cost. Therefore, there is an urgent need to transform the development and further improve the enhanced oil recovery (EOR). In this paper, the mechanism of EOR by polymer flooding was investigated for high-porosity and high-permeability terrestrial ordinary heavy oil reservoirs. Through laboratory experiments, we analyzed the characteristics of oil-water relative permeability curves, mobility control ability, and microscopic seepage characteristics during polymer flooding of ordinary heavy oil reservoirs. On this basis, the effect of the mobility ratio on seepage characteristics and the mechanism of EOR enhancement were clarified. The results show that the polymer can effectively improve the mobility control effect of the displacing fluid. As the polymer solution and ordinary heavy oil have the characteristics of high viscosity and low mobility, there is a minimum mobility ratio in the process of polymer flooding. Namely, the characteristics of dual low mobility exist in the process of polymer flooding for the ordinary heavy oil. It effectively enhances the profile control and plugging ability of the polymer, thus expanding the sweep volume of larger pores and improving the displacement efficiency of smaller pores. Based on the two factors mentioned above, it is found that the dual low mobility characteristics can improve the recovery of ordinary heavy oil by polymer flooding. Therefore, it is proposed that an enhanced profile control and plugging effect due to the dual low mobility characteristics is an important EOR mechanism for ordinary heavy oil development by polymer flooding.

Effect of modification degrees on the interfacial properties and EOR efficiency of amphiphilic Janus graphene oxide

Asymmetrically modified Janus graphene oxide (JGO) has attracted great attention due to its unique physical chemistry properties and wide applications. The modification degree of Janus nanosheets inevitably affects their interfacial activity, which is essential for their performances in enhanced oil recovery (EOR). In this study, the interfacial properties of Janus graphene oxide (JGO) with various modification degrees at liquid-liquid and liquid-solid interfaces were systematically evaluated via the measurements of interfacial tension (IFT), dilatational modulus, contact angle, and EOR efficiency was further assessed by core flooding tests. It is found that JGO-5 with higher modification degree exhibits the greater ability to reduce IFT (15.16 mN/m) and dilatational modulus (26 mN/m). Furthermore, JGO can construct interfacial and climbing film with the assistance of hydrodynamic power to effectively detach the oil from the rock surface and greatly enhance oil recovery. Moderately modified JGO-2 can highly improve recovery of residual crude oil (11.53%), which is regarded as the promising EOR agent in practical application. The present study firstly focuses on the effects of modification degrees on the JGO interfacial properties and proposes diverse EOR mechanisms for JGO with different modification degrees.

Research progress and prospect of silica-based polymer nanofluids in enhanced oil recovery

Abstract In recent years, silica-based polymer nanofluids (NFs) have attracted more and more attention because they can enhance temperature and salt tolerance. This study summarized the research progress and prospects of silica-based polymer NFs in enhanced oil recovery (EOR). First, the synthesis method and the effect on silica-based polymer NFs were studied. Research progress in rheology, wettability, viscoelasticity, interfacial tension, adsorption, porous media flow, and emulsion stability were reviewed, and the mechanism for EOR was expounded. Then, the mechanical properties of silica-based polymer NFs and the interaction between silica and polymer were discussed by molecular dynamics simulation. And the progress of research on macroscopic reservoir simulation was explored. Finally, the related auxiliary technologies were introduced, and future research directions were put forward. The results of this study will help researchers better understand the mechanism and research progress of silica-based polymer NFs in EOR.

Experimental and Computational Fluid Dynamics Investigation of Mechanisms of Enhanced Oil Recovery via Nanoparticle-Surfactant Solutions

The enhancement in surfactant performance at downhole conditions in the presence of nanomaterials has fascinated researchers’ interest regarding the applications of nanoparticle-surfactant (NPS) fluids as novel enhanced oil recovery (EOR) techniques. However, the governing EOR mechanisms of hydrocarbon recovery using NPS solutions are not yet explicit. Pore-scale visualization experiments clarify the dominant EOR mechanisms of fluid displacement and trapped/residual oil mobilization using NPS solutions. In this study, the influence of multiwalled carbon nanotubes (MWCNTs), silicon dioxide (SiO2), and aluminum oxide (Al2O3) nanoparticles on the EOR properties of a conventional surfactant (sodium dodecyl benzene sulfonate, SDBS) was investigated via experimental and computational fluid dynamics (CFD) simulation approaches. Oil recovery was reduced with increased temperatures and micromodel heterogeneity. Adding nanoparticles to SDBS solutions decreases the fingering and channeling effect and increases the recovery factor. The simulation prediction results agreed with the experimental results, which demonstrated that the lowest amount of oil (37.84%) was retained with the micromodel after MWCNT-SDBS flooding. The oil within the micromodel after Al2O3-SDBS and SiO2-SDBS flooding was 58.48 and 43.42%, respectively. At 80 °C, the breakthrough times for MWCNT-SDBS, Al2O3-SDBS, and SiO2-SDBS displacing fluids were predicted as 32.4, 29.3, and 21 h, respectively, whereas the SDBS flooding and water injections at similar situations were at 12.2 and 6.9 h, respectively. The higher oil recovery and breakthrough time with MWCNTs could be attributed to their cylindrical shape, promoting the MWCNT-SDBS orientation at the liquid–liquid and solid–liquid interfaces to reduce the oil–water interfacial tension and contact angles significantly. The study highlights the prevailing EOR mechanisms of NPS.