Enhancing Oil Recovery with Hydrophilic Polymer-Coated Silica Nanoparticles

Nanoparticles (NPs) have been proposed for enhanced oil recovery (EOR). The research has demonstrated marvelous effort to realize the mechanisms of nanoparticles EOR. Nevertheless, gaps still exist in terms of understanding the nanoparticles-driven interactions occurring at fluids and fluid–rock interfaces. Surface-active polymers or other surface additive materials (e.g., surfactants) have shown to be effective in aiding the dispersion stability of NPs, stabilizing emulsions, and reducing the trapping or retention of NPs in porous media. These pre-requisites, together with the interfacial chemistry between the NPs and the reservoir and its constituents, can result in an improved sweep efficiency. This paper investigates four types of polymer-coated silica NPs for the recovery of oil from water-wet Berea sandstones. A series of flooding experiments was carried out with NPs dispersed at 0.1 wt.% in seawater in secondary and tertiary oil recovery modes at ambient conditions. The dynamic interactions of fluids, fluid–rock, and the transport behavior of injected fluid in the presence of NPs were, respectively, studied by interfacial tension (IFT), spontaneous imbibition tests, and a differential pressure analysis. Core flooding results showed an increase in oil recovery up to 14.8% with secondary nanofluid injection compared to 39.7% of the original oil in place (OOIP) from the conventional waterflood. In tertiary mode, nanofluids increased oil recovery up to 9.2% of the OOIP. It was found that no single mechanism could account for the EOR effect with the application of nanoparticles. Instead, the mobilization of oil seemed to occur through a combination of reduced oil/water IFT, change in the rock surface roughness and wettability, and microscopic flow diversion due to clogging of the pores.

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Effect of pressure variation on polymer flooding

10.32920/ryerson.14663814 ◽

2021 ◽

Author(s):

Ahmad Ali Manzoor

Keyword(s):

Polymer Solution ◽

Enhanced Oil Recovery ◽

Oil Recovery ◽

Heavy Oil ◽

Constant Pressure ◽

Maximum Pressure ◽

Core Flooding ◽

Sweep Efficiency ◽

Black Oil Model ◽

Original Oil In Place

Chemical-based enhanced oil recovery (EOR) techniques utilize the injection of chemicals, such as solutions of polymers, alkali, and surfactants, into oil reservoirs for incremental recovery. The injection of a polymer increases the viscosity of the injected fluid and alters the water-to-oil mobility ratio which in turn improves the volumetric sweep efficiency. This research study aims to investigate strategies that would help intensify oil recovery with the polymer solution injection. For that purpose, we utilize a lab-scale, cylindrical heavy oil reservoir model. Furthermore, a dynamic mathematical black oil model is developed based on cylindrical physical model of homogeneous porous medium. The experiments are carried out by injecting classic and novel partially hydrolyzed polyacrylamide solutions (concentration: 0.1-0.5 wt %) with 1 wt % brine into the reservoir at pressures in the range, 1.03-3.44 MPa for enhanced oil recovery. The concentration of the polymer solution remains constant throughout the core flooding experiment and is varied for other subsequent experimental setup. Periodic pressure variations between 2.41 and 3.44 MPa during injection are found to increase the heavy oil recovery by 80% original-oil-in-place (OOIP). This improvement is approximately 100% more than that with constant pressure injection at the maximum pressure of 3.44 MPa. The experimental oil recoveries are in fair agreement with the model calculated oil production with a RMS% error in the range of 5-10% at a maximum constant pressure of 3.44 MPa.

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Experimental Investigation of Polymer-Coated Silica Nanoparticles for Enhanced Oil Recovery

Nanomaterials ◽

10.3390/nano9060822 ◽

2019 ◽

Vol 9 (6) ◽

pp. 822 ◽

Cited By ~ 12

Author(s):

Alberto Bila ◽

Jan Åge Stensen ◽

Ole Torsæter

Keyword(s):

Silica Nanoparticles ◽

Enhanced Oil Recovery ◽

Oil Recovery ◽

Wettability Alteration ◽

Rock Surface ◽

Minor Effect ◽

Core Flooding ◽

Ambient Conditions ◽

The North ◽

Particle Retention

Recently, polymer-coated nanoparticles were proposed for enhanced oil recovery (EOR) due to their improved properties such as solubility, stability, stabilization of emulsions and low particle retention on the rock surface. This work investigated the potential of various polymer-coated silica nanoparticles (PSiNPs) as additives to the injection seawater for oil recovery. Secondary and tertiary core flooding experiments were carried out with neutral-wet Berea sandstone at ambient conditions. Oil recovery parameters of nanoparticles such as interfacial tension (IFT) reduction, wettability alteration and log-jamming effect were investigated. Crude oil from the North Sea field was used. The concentrated solutions of PSiNPs were diluted to 0.1 wt % in synthetic seawater. Experimental results show that PSiNPs can improve water flood oil recovery efficiency. Secondary recoveries of nanofluid ranged from 60% to 72% of original oil in place (OOIP) compared to 56% OOIP achieved by reference water flood. In tertiary recovery mode, the incremental oil recovery varied from 2.6% to 5.2% OOIP. The IFT between oil and water was reduced in the presence of PSiNPs from 10.6 to 2.5–6.8 mN/m, which had minor effect on EOR. Permeability measurements indicated negligible particle retention within the core, consistent with the low differential pressure observed throughout nanofluid flooding. Amott–Harvey tests indicated wettability alteration from neutral- to water-wet condition. The overall findings suggest that PSiNPs have more potential as secondary EOR agents than tertiary agents, and the main recovery mechanism was found to be wettability alteration.

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Effect of pressure variation on polymer flooding

10.32920/ryerson.14663814.v1 ◽

2021 ◽

Author(s):

Ahmad Ali Manzoor

Keyword(s):

Polymer Solution ◽

Enhanced Oil Recovery ◽

Oil Recovery ◽

Heavy Oil ◽

Constant Pressure ◽

Maximum Pressure ◽

Core Flooding ◽

Sweep Efficiency ◽

Black Oil Model ◽

Original Oil In Place

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Investigation into the Functions of Alkali and Surfactant in Chemical Flooding for Enhanced Heavy-Oil Recovery

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.524-527.1816 ◽

2012 ◽

Vol 524-527 ◽

pp. 1816-1820 ◽

Cited By ~ 1

Author(s):

Ji Jiang Ge ◽

Hai Hua Pei ◽

Gui Cai Zhang ◽

Xiao Dong Hu ◽

Lu Chao Jin

Keyword(s):

Oil Recovery ◽

Heavy Oil ◽

Chemical Flooding ◽

Surfactant Flooding ◽

Core Flooding ◽

Sweep Efficiency ◽

Water Emulsion ◽

Tertiary Oil Recovery ◽

Fingering Phenomena ◽

Oil In Water Emulsion

In this study, a comparative study of alkaline flooding and alkali-surfactant flooding were conducted for Zhuangxi heavy oil with viscosity of 325 mPa•s at 55 °C. The results of core flooding tests show that the tertiary oil recovery of alkali-surfactant flooding are lower than those of alkaline-only flooding, in spite of the coexistence of the surfactant and alkali can reduce the IFT between the heavy oil and aqueous phase to an ultralow level. Further flood study via glass-etching micromodel tests demonstrates that injected alkaline-only solution can penetrate into the oil phase and creates some discontinuous water droplet inside the oil phase that tend to lower the mobility of the injected water and lead to the improvement of sweep efficiency. While for alkali-surfactant flooding, heavy oil is easily emulsified in brine by an alkaline plus very dilute surfactant formula to form oil-in-water emulsion, and then entrained in the water phase. Therefore, viscous fingering phenomena occur during the alkali-surfactant flooding, resulting in relatively lower sweep efficiency.

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Enhancing Oil Recovery with Hydrophilic Polymer-Coated Silica Nanoparticles

10.20944/preprints202009.0615.v1 ◽

2020 ◽

Author(s):

Alberto Bila ◽

Ole Torsæter

Keyword(s):

Silica Nanoparticles ◽

Oil Recovery ◽

Driving Forces ◽

Flow Behavior ◽

Water Flooding ◽

Rock Surface ◽

Ambient Conditions ◽

Recovery Mechanisms ◽

Rock Interface ◽

Original Oil In Place

Nanoparticles have been proposed for enhanced oil recovery (EOR). The research has demonstrated marvelous effort to understand the mechanisms of nanoparticles-EOR. Nevertheless, gaps still exist in terms of understanding the improved fluids and fluid-rock interactions by nanoparticles, which are the key driving forces for oil mobilization. This paper investigates four types of polymer-coated silica nanoparticles as additives for water flooding oil recovery in water-wet reservoirs. A series of flooding experiments were performed with nanoparticles at 0.1 wt.% in seawater at ambient conditions. The dynamics of fluids, fluid-rock interface interactions and fluid flow behavior were characterized in order to understand oil recovery mechanisms of nanoparticles. Experimental results showed an increase in oil recovery up to 14.8%-point with nanofluid injection compared to an average of 40% of the original oil in place (OOIP) obtained from control water flood test. Moreover, the nanoparticles mobilized residual oil and incremented oil recovery up to 9.2% of the OOIP. Displacement studies show that no single mechanism could account for the EOR effect with the application of nanoparticles. Instead, the mobilization of oil seemed to occur through a combination of reduced oil/water IFT, change in the rock surface roughness and wettability to more water-wet, and microscopic flow diversion due to clogging of the pores.

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Modification of Xanthan Gum for a High-Temperature and High-Salinity Reservoir

Polymers ◽

10.3390/polym13234212 ◽

2021 ◽

Vol 13 (23) ◽

pp. 4212

Author(s):

Mohamed Said ◽

Bashirul Haq ◽

Dhafer Al Shehri ◽

Mohammad Mizanur Rahman ◽

Nasiru Salahu Muhammed ◽

...

Keyword(s):

High Temperature ◽

Oil Recovery ◽

Xanthan Gum ◽

Elevated Temperatures ◽

High Salinity ◽

Residual Oil ◽

Core Flooding ◽

Nacl Solution ◽

The Core ◽

Tertiary Oil Recovery

Tertiary oil recovery, commonly known as enhanced oil recovery (EOR), is performed when secondary recovery is no longer economically viable. Polymer flooding is one of the EOR methods that improves the viscosity of injected water and boosts oil recovery. Xanthan gum is a relatively cheap biopolymer and is suitable for oil recovery at limited temperatures and salinities. This work aims to modify xanthan gum to improve its viscosity for high-temperature and high-salinity reservoirs. The xanthan gum was reacted with acrylic acid in the presence of a catalyst in order to form xanthan acrylate. The chemical structure of the xanthan acrylate was verified by FT-IR and NMR analysis. The discovery hybrid rheometer (DHR) confirmed that the viscosity of the modified xanthan gum was improved at elevated temperatures, which was reflected in the core flood experiment. Two core flooding experiments were conducted using six-inch sandstone core plugs and Arabian light crude oil. The first formulation—the xanthan gum with 3% NaCl solution—recovered 14% of the residual oil from the core. In contrast, the modified xanthan gum with 3% NaCl solution recovered about 19% of the residual oil, which was 5% higher than the original xanthan gum. The xanthan gum acrylate is therefore more effective at boosting tertiary oil recovery in the sandstone core.

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Labortory and Pilot Tests of Enhanced Oil Recovery through Wettability Alteration by Diluted Microemulsions

10.2118/204291-ms ◽

2021 ◽

Author(s):

Xurong Zhao ◽

Tianbo Liang ◽

Jingge Zan ◽

Mengchuan Zhang ◽

Fujian Zhou ◽

...

Keyword(s):

Oil Recovery ◽

Water Saturation ◽

Wettability Alteration ◽

Rock Surface ◽

Core Flooding ◽

Fracturing Fluid ◽

Invasion Front ◽

Wetting Ability ◽

On Line ◽

Wet Rocks

Abstract Replacing oil from small pores of tight oil-wet rocks relies on altering the rock wettability with the injected fracturing fluid. Among different types of wettability-alteration surfactants, the liquid nanofluid has less adsorption loss during transport in the porous media, and can efficiently alter the rock wettability; meanwhile, it can also maintain a certain oil-water interfacial tension driving the water imbibition. In the previous study, the main properties of a Nonionic nanofluid-diluted microemulsion (DME) were evaluated, and the dispersion coefficient and adsorption rate of DME in tight rock under different conditions were quantified. In this study, to more intuitively show the change of wettability of DME to oil-wet rocks in the process of core flooding experiments and the changes of the water invasion front, CT is used to carry out on-line core flooding experiments, scan and calculate the water saturation in time, and compare it with the pressure drop in this process. Besides, the heterogeneity of rock samples is quantified in this paper. The results show that when the DME is used as the fracturing fluid additive, fingering of the water phase is observed at the beginning of the invasion; compared with brine, the fracturing fluid with DME has deeper invasion depth at the same time; the water invasion front gradually becomes uniform when the DME alters the rock wettability and triggers the imbibition; for tight rocks, DME can enter deeper pores and replace more oil because of its dominance. Finally, the selected nanofluids of DME were tested in two horizontal wells in the field, and their flowback fluids were collected and analyzed. The results show that the average droplet size of the flowback fluids in the wells using DME decreases with production time, and the altered wetting ability gradually returns to the level of the injected fracturing fluid. It can be confirmed that DME can migrate within the tight rock, make the rock surface more water-wet and enhance the imbibition capacity of the fracturing fluid, to reduce the reservoir pressure decline rate and increase production.

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Compatibility evaluation of modified seawater for EOR in carbonate reservoirs through the introduction of polyphosphate compound

Petroleum Science ◽

10.1007/s12182-019-00380-6 ◽

2019 ◽

Vol 17 (2) ◽

pp. 393-408 ◽

Cited By ~ 1

Author(s):

Bisweswar Ghosh ◽

Liying Sun ◽

Nithin Chacko Thomas

Keyword(s):

Oil Recovery ◽

Economic Benefits ◽

Carbonate Reservoir ◽

Carbonate Reservoirs ◽

Core Flooding ◽

Systematic Screening ◽

Flood Water ◽

Scaling Potential ◽

Original Oil In Place ◽

New Formulation

Abstract Waterflood-assisted oil recovery with sulfate-spiked seawater would cause incompatibility scaling in carbonate reservoirs and reduce economic benefits. This research investigated the benefits of polyphosphate compounds in reducing scaling potential as well as its effect on oil recovery when mixed in high sulfate flood water. Severity of scaling potential of sulfate-spiked water in a carbonate reservoir environment was measured, followed by systematic screening of a polyphosphate compound, which successfully inhibited the sulfate scale precipitation at concentration as low as 100 ppm. The new formulation (seawater with four times sulfate and phosphate, SW4SP) was evaluated and compared with benchmark formulation (modified seawater with four times sulfate, SW4S). Contact angle, ζ-potential and drainage studies show that SW4SP changed the rock wettability from oil wet to water wet to a larger degree compared to SW4S. Improved recovery efficiency of SW4SP was confirmed through a set of core flooding studies in the tertiary and quaternary flood modes. Whereas SW4S recovered 7.7% of original oil in place (OOIP), SW4SP recovered about 8% of OOIP in the tertiary mode under approximately identical flow conditions. Flooding with SW4SP in the quaternary mode following a tertiary flood with SW4S on the same core resulted in 1.7% additional oil recovery, showing improved efficiency of the new flood water formulation.

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Polymer-functionalized silica nanoparticles for improving water flood sweep efficiency in Berea sandstones

E3S Web of Conferences ◽

10.1051/e3sconf/202014602001 ◽

2020 ◽

Vol 146 ◽

pp. 02001 ◽

Cited By ~ 2

Author(s):

Alberto Bila ◽

Jan Åge Stensen ◽

Ole Torsæter

Keyword(s):

Porous Media ◽

Oil Recovery ◽

Functionalized Silica ◽

Sweep Efficiency ◽

Rock System ◽

Injection Water ◽

Improved Stability ◽

Production Stages ◽

Incremental Oil Recovery ◽

Original Oil In Place

Extraction of oil trapped after primary and secondary oil production stages still poses many challenges in the oil industry. Therefore, innovative enhanced oil recovery (EOR) technologies are required to run the production more economically. Recent advances suggest renewed application of surface-functionalized nanoparticles (NPs) for oil recovery due to improved stability and solubility, stabilization of emulsions, and low retention on porous media. The improved surface properties make the NPs more appropriate to improve microscopic sweep efficiency of water flood compared to bare nanoparticles, especially in challenging reservoirs. However, the EOR mechanisms of NPs are not well understood. This work evaluates the effect of four types of polymer-functionalized silica NPs as additives to the injection water for EOR. The NPs were examined as tertiary recovery agents in water-wet Berea sandstone rocks at 60 °C. The NPs were diluted to 0.1 wt. % in seawater before injection. Crude oil was obtained from North Sea field. The transport of NPs though porous media, as well as nanoparticles interactions with the rock system, were investigated to reveal possible EOR mechanisms. The experimental results showed that functionalized-silica NPs can effectively increase oil recovery in water-flooded reservoirs. The incremental oil recovery was up to 14% of original oil in place (OOIP). Displacement studies suggested that oil recovery was affected by both interfacial tension reduction and wettability modification, however, the microscopic flow diversion due to pore plugging (log-jamming) and the formation of nanoparticle-stabilized emulsions were likely the relevant explanations for the mobilization of residual oil.

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Characteristics of a Geobacillus sp. as an Enhanced Oil Recovery Material

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.496.542 ◽

2012 ◽

Vol 496 ◽

pp. 542-545

Author(s):

Xiang Ping Kong

Keyword(s):

Crude Oil ◽

Enhanced Oil Recovery ◽

Oil Recovery ◽

Sewage Treatment ◽

Core Flooding ◽

Treatment Technology ◽

Promising Candidate ◽

Different Types ◽

Displacement Experiments ◽

Original Oil In Place

The enhanced oil recovery characteristics of a Geobacillus sp. was investigated by shake flask experiments, blind-tube oil displacement experiments and core flooding tests. The strain exhibited good properties such as resisting high temperature, taking different types of crude oil as the sole carbon source, reducing the viscosity of crude oil, emulsifying and dispersing crude oil or liquid wax. The oil in the dead area could be effectively driven out by the strain, and the oil recovery of original oil in place had been increased by 12.9-15.9% after 5 treatments in 50 days by adopting air-assistant technique (air/liquid 10:1, v/v) due to the synergistic effect of the bacteria and their metabolites such as biogas and biosurfactants. The strain seems to be a promising candidate for microbial enhanced oil recovery and underground sewage treatment technology.

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