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Foam-enhanced oil recovery (EOR) is poised to become one of the most promising tertiary recovery techniques to keep up with the continuously increasing global energy demands. Due to their low sensitivity to gravity and permeability heterogeneities that improve sweep efficiency, foams are the preferred injection fluids over water or gas. Although fo...
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... reservoir is typically heated with steam or hot water injections to reduce oil viscosity and increase its mobility to the surface for production. Figure 1 provides a summary of the various techniques. Enhanced oil recovery generally aims to boost sweep efficiency both on a macroscopic scale and a microscopic scale. ...
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... seen in Figure 10, the leave-behind occurs when two gas menisci enter the adjacent branching pore bodies that are filled with liquid. ...
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... (b) Figure 10. Leave-behind mechanism of foam generation in the porous media (Adapted from Ransohoh et al. [80]). ...
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... diffusion (Ostwald ripening, bubble disproportionation) is the most crucial mechanism since it underlies all the other mechanisms (drainage and coalescence), making it the cause of foam instability. The stages that foam can go through before being completely destroyed are depicted in Figure 11. While some foams undergo the whole stages, others collapse as a result of an external disturbance [88]. ...
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... as pressure rises, less gas will diffuse between the lamellae, thus increasing foam stability. Wang et al. [109] demonstrate this ( Figure 13) phenomenon. In this study, the performance of foam under high pressure and temperature conditions was investigated using a visualizing foam meter. ...
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... causes the foam to become more unstable by increasing liquid drainage [60]. The viscosity and elasticity of the foam lamella will decrease at higher temperatures, which will have a significant impact on the performance of the foam although the extent of the deterioration of foam stability may depend on the chemical composition or hydrocarbon chain length of the foaming agent used (Figure 14). The work of Wang et al. [110] also demonstrates how temperature affects foam stability. ...
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... 2 . Figure 15 below demonstrates that foam stability is only improved at low salinity, and stability degrades when a salt content goes above 2%. The authors attributed this to the forceful deposition of additional ions on the surface of the foam film, which led to a partial neutralization of the electric charges. ...
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... C 12 was employed as the foaming agent. According to their findings, the foam was noticeably more stable at higher salinity ( Figure 16 According to the authors, the success of this interaction at higher salinity was due to the compression of the electrical double layer and an increase in the maximum disjoining pressure at higher salinity. Bello et al. [60] asserted that bubble coalescence typically begins early in many surfactants at high salinity conditions, which worsens the foam stability. ...
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... the inclusion of steamed foam helped in limiting steam breakthrough and produced superior recovery results than the traditional SAGD. Cumulative oil recovery was increased by roughly 30% with FASAGD compared to the cases without foam (Figure 17). A comprehensive summary of laboratory foam-EOR experiments is given in Table 2 below: ...
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... refers to the attraction and repulsive force between thin layers at the surfaces of two fluids [195]. Figure 18 below shows that nanoparticles form microstructures in enclosed areas, such as foams, gels, and emulsions. This adds a third interface to the two that already exist. ...
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... experiments were conducted at ambient and elevated temperatures and with a wide range of salinity. As it can be seen in Figure 19, their results showed that indeed, nanoparticles can increase foam stability by reinforcing the thin liquid film between foam bubbles, thereby reducing liquid drainage rate and forming a stronger and more stable foam. Ionic liquids are a new group of chemical blends that can be used to improve foam stability. ...
Citations
... Modified Commonly used methods for EOR. Represented from Bello et al. [11]. relative permeability curves confirmed the change in wettability. ...
As the oil and gas industry continues to evolve, the utilization of advanced materials becomes crucial for maximizing efficiency and productivity. Nanoemulsions (NEs) have emerged as a promising solution for various downhole applications. Their unique properties, enhanced stability, and improved performance have led to applications in enhanced oil recovery, drilling fluids, fracturing fluids, and produced water treatment. However, while NEs offer significant advantages, production costs, stability during transportation and storage, as well as scale-up challenges must be carefully considered. This chapter aims to provide an overview of NEs for oil and gas applications, discussing the current benchmark, potential implementation, properties, and various applications. Furthermore, it will provide recommendations and insights on how to effectively implement NEs in the field. It is important to recognize that the ongoing research and development efforts hold the potential to further revolutionize the oil and gas applications and contribute to a more sustainable processes and operations.
... The foam lamella acts as a physical barrier that hinders the movement of gas, allowing for a more efficient oil displacement. 42,43 This restriction of gas mobility helps to ensure that the injected gas reaches a more significant portion of the reservoir, enhancing oil recovery. 26,37,44 One of the significant challenges associated with surfactantstabilized foams is their inherent instability due to the abrupt disintegration of the thin liquid layers present at the interface or boundary between gas and liquid phases. ...
The enhanced oil recovery techniques are ever-evolving to cater to the need for increased oil demand. To improve the EOR efficiency, the new approach combines chemical additives like nanoparticles and surfactants with carbonated water to address the issues of reduced mobility control, gravity segregation, and early breakout encountered in CO2 flooding. The in-situ generated CO2 foams are unstable structures depending upon additional additives to strengthen their lamella and improve their stability, which ZnO nanoparticles (NPs) provide in the current study. This research investigates the synergistic impact of sodium dodecyl sulfate (SDS) and ZnO NPs on CO2 foam generated from carbonated water. The carbonated water flooding tests were conducted using optimal SDS and ZnO concentrations of 2500 ppm and 0.01 wt%, respectively. The processes underlying the synergistic action of SDS and ZnO are altering nanoparticle adsorption sites on the CO2 and liquid interface, enhancing the CO2 foam's interfacial characteristics, and lowering its liquid discharge and coarsening. Further, four flooding procedures were utilized on two sandstone cores with contrasting petrophysical characteristics to study the effect of foam-assisted carbonated water flooding. The oil recovery was influenced and increased by SDS and ZnO NPs. The outcomes show that CO2 foam flooding (nanoparticles included) generated using carbonated slug illustrates effective conformance control and enhances oil recovery from sandstone. It has been observed that nano-surfactant-added carbonated slug flooding gives a 50.00% and 194.72% recovery enhancement compared to regular carbonated water flooding for sandstone-1 and sandstone-2, respectively.
... Foam injection is one of the EOR methods that is considered in this study. Foam is a non-wetting gas dispersion into a continuous liquid wetting phase [5,6]. Surfactant or polymer solutions are frequently used as the liquid wetting phase. ...
Oil reservoirs are nearing maturation, necessitating novel enhanced oil recovery (EOR) techniques to meet escalating global energy demands. This demand has spurred interest in reservoir production analysis and forecasting tools to enhance economic and technical efficiency. Accurate validation of these tools, known as simulators, using laboratory or field data is pivotal for precise reservoir productivity estimation. This study delves into the application of nanoparticles in foam flooding for mobility control to improve sweep efficiency. Foam generation can occur in-situ by simultaneous injection of surfactants and gas or through pre-generated foam injection into the reservoir. In this work, a series of systematic simulations were run to investigate how much injected fluids can reduce gas breakthrough while also increasing oil recovery. Subsequently, we analyzed the most effective optimization strategies, considering their economic limits. Our primary objective is to numerically model nanofoam flooding as an innovative EOR approach, synergizing foam flooding mechanisms with nanotechnology benefits. In this work, modeling of nanoparticles in foam liquid was represented by the interfacial properties provided to the injection fluid. Additionally, we simulated Water-Alternating-Gas (WAG) injection schemes across various cycles, comparing their outcomes. Our results showed that nanofoam injection achieved a higher recovery factor of at least 38% and 95% more than WAG and gas injections, respectively. The superior efficiency and productivity of foam injection compared to WAG and gas injection suggest an optimal EOR approach within the scope of our model. These simulated optimization techniques contribute to the future development of processes in this field.
... Gemini surfactants with 0. Surfactant−crude oil compatibility is a pivotal consideration in enhanced oil recovery and other oilfield applications. 82 For optimal performance, surfactants need to be soluble within the crude oil phase, enabling them to significantly reduce the interfacial tension. This compatibility ensures their effective migration into the oil phase, enabling the formation of micelles that mitigate the capillary forces responsible for entrapping oil within the rock pores. ...
... The capacity of the foam to move through the reservoir and displace the trapped oil is determined by foam stability, which is critical for effective EOR applications. 82 When contrasted to the oil in the reservoir, foam works as a mobility control agent, lowering the mobility of the displacing fluid (gas−liquid foam). The restricted mobility of the foam improves the sweep efficiency by contacting a wider section of the reservoir and increasing the displacement of trapped oil. ...
The use of different types of chemicals in upstream oilfield operations is critical for optimizing the different operations involved in hydrocarbon exploration and production. Surfactants are a type chemical that are applied in various upstream operations, such as drilling, fracturing, and enhanced oil recovery. However, due to their nonbiodegradability and toxicity, the use of synthetic surfactants has raised environmental concerns. Natural surfactants have emerged because of the hunt for sustainable and environmentally suitable substitutes. This Review discusses the role of natural surfactants in upstream operations as well as their benefits and drawbacks. The Review discusses the basic characteristics of surfactants, their classification, and the variables that affect their performance. Finally, the Review examines the possible applications of natural surfactants in the upstream oil sector and identifies areas that require further research.
... By improving the volumetric sweep efficiency and lowering gas mobility, foam increases the efficiency of gas EOR. This has led to the active development and optimisation of foam EOR technology [11][12][13] Foam, a gas-and-liquid mixture, has been found to improve sweep efficiency during gas injection, increase gas storage in the reservoir and lower the gas-to-oil ratio [14,15]. However, due to foam instability and the risk of pore blockage, it is not frequently employed in field conditions. ...
Foams have been successfully implemented to overcome the challenges associated with gas-enhanced oil recovery (EOR) over time. Generally, the foam helps to increase the viscosity of the injected gas, which in turn improves the effectiveness of EOR. However, this technology has rarely been applied in the oilfield due to technological and economical limitations. It is widely considered that nanoparticles may be added to foam to enhance its performance in harsh reservoir conditions to overcome some of these limitations. In this study, we employed high-pressure microscopy (HPM) as an advanced technique to examine the stability of N2 and CO2 foams at reservoir conditions, both with and without nanoparticles. The experiments were conducted under vapour and supercritical conditions. Our results indicated that foams produced at 80% quality were more stable than foams produced at 50% quality because the bubble size was significantly smaller and the bubble count was higher. Additionally, foams under supercritical conditions (sc) exhibited greater stability than foams under vapour conditions. This is because at supercritical conditions, the high density of gases helps to strengthen the foam lamella by enhancing the intermolecular contacts between the gas and the hydrophobic part of the liquid phase. Furthermore, core flooding studies were performed to investigate their effect on oil displacement and mobility control in both real and artificial core samples. Rather than focusing on precise quantitative results, our objective was to assess the effect of foams on oil recovery qualitatively. The results indicated that foam injection could significantly increase displacement efficiency, as foam injection raised total displacement efficiency from an initial 48.9% to 89.7% in the artificial core sample. Similarly, in the real core model, CO2 foam injection was implemented as a tertiary recovery method, and a recovery factor of 28.91% was obtained. These findings highlight the potential benefits of foams for EOR purposes and their ability to mitigate early gas breakthrough, which was observed after injecting approximately 0.14 PV during scCO2 injection.
A key factor affecting foam stability is the interaction of foam with oil in the reservoir. This work investigates how different types of oil influence the stability of foams generated with binary surfactant systems under a high salinity condition. Foam was generated with binary surfactant systems, one composed of a zwitterionic and a nonionic surfactant, and the other composed of an anionic and a nonionic surfactant. Our results showed that the binary surfactant foams investigated are more tolerant under high salinity conditions and in the presence of oil. This was visually observed in our microscopic analysis and was further attributed to an increase in apparent viscosity achieved with binary surfactant systems, compared to single surfactant foams. To understand the influence of oil on foam stability, we performed a mechanistic study to investigate how these oils interact with foams generated with binary surfactants, focusing on their applicability under high salinity conditions. The generation and stability of foam are linked to the ability of the surfactant system to solubilize oil molecules. Oil droplets that solubilize in the micelles appear to destabilize the foam. However, oils with higher molecular weights are too large to be solubilized in the micelles, hence the molecules will have less ability to be transported out of the foam, so oil seems to stabilize the foam. Finally, we conducted a multivariate analysis to identify the parameters that influenced foam stability in different oil types, using the experimental data from our work. The results showed that the oil molecular weight, interfacial tension between the foaming liquid and the oil, and the spreading coefficient are the most important variables for explaining the variation in the data. By performing a partial least square regression, a linear model was developed based on these most important variables, which can be used to predict foam stability for subsequent experiments under the same conditions as our work.
