Introduction to Enhanced Oil Recovery (EOR) Processes and Bioremediation of Oil-Contaminated Sites

The traditional Enhanced Oil Recovery (EOR) processes allow improving the performance of mature oilfields after waterflooding projects. Chemical EOR processes modify different physical properties of the fluids and/or the rock in order to mobilize the oil that remains trapped. Furthermore, combined processes have been proposed to improve the performance, using the properties and synergy of the chemical agents. This paper presents a novel simulator developed for a combined surfactant/polymer flooding in EOR processes. It studies the flow of a two-phase, five-component system (aqueous and organic phases with water, petroleum, surfactant, polymer and salt) in porous media. Polymer and surfactant together affect each other’s interfacial and rheological properties as well as the adsorption rates. This is known in the industry as Surfactant-Polymer Interaction (SPI). The simulations showed that optimum results occur when both chemical agents are injected overlapped, with the polymer in the first place. This procedure decreases the surfactant’s adsorption rates, rendering higher recovery factors. The presence of the salt as fifth component slightly modifies the adsorption rates of both polymer and surfactant, but its influence on the phase behavior allows increasing the surfactant’s sweep efficiency.

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Nanotechnology Applied to Thermal Enhanced Oil Recovery Processes: A Review

Energies ◽

10.3390/en12244671 ◽

2019 ◽

Vol 12 (24) ◽

pp. 4671 ◽

Cited By ~ 12

Author(s):

Oscar E. Medina ◽

Carol Olmos ◽

Sergio H. Lopera ◽

Farid B. Cortés ◽

Camilo A. Franco

Keyword(s):

Enhanced Oil Recovery ◽

Oil Recovery ◽

New Technologies ◽

Enhanced Recovery ◽

Thermal Recovery ◽

Wettability Alteration ◽

Crude Oils ◽

Recovery Processes ◽

Heavy Crude ◽

Eor Processes

The increasing demand for fossil fuels and the depleting of light crude oil in the next years generates the need to exploit heavy and unconventional crude oils. To face this challenge, the oil and gas industry has chosen the implementation of new technologies capable of improving the efficiency in the enhanced recovery oil (EOR) processes. In this context, the incorporation of nanotechnology through the development of nanoparticles and nanofluids to increase the productivity of heavy and extra-heavy crude oils has taken significant importance, mainly through thermal enhanced oil recovery (TEOR) processes. The main objective of this paper is to provide an overview of nanotechnology applied to oil recovery technologies with a focus on thermal methods, elaborating on the upgrading of the heavy and extra-heavy crude oils using nanomaterials from laboratory studies to field trial proposals. In detail, the introduction section contains general information about EOR processes, their weaknesses, and strengths, as well as an overview that promotes the application of nanotechnology. Besides, this review addresses the physicochemical properties of heavy and extra-heavy crude oils in Section 2. The interaction of nanoparticles with heavy fractions such as asphaltenes and resins, as well as the variables that can influence the adsorptive phenomenon are presented in detail in Section 3. This section also includes the effects of nanoparticles on the other relevant mechanisms in TEOR methods, such as viscosity changes, wettability alteration, and interfacial tension reduction. The catalytic effect influenced by the nanoparticles in the different thermal recovery processes is described in Sections 4, 5, 6, and 7. Finally, Sections 8 and 9 involve the description of an implementation plan of nanotechnology for the steam injection process, environmental impacts, and recent trends. Additionally, the review proposes critical stages in order to obtain a successful application of nanoparticles in thermal oil recovery processes.

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Wettability alteration analysis of smart water/novel functionalized nanocomposites for enhanced oil recovery

Petroleum Science ◽

10.1007/s12182-020-00436-y ◽

2020 ◽

Vol 17 (5) ◽

pp. 1318-1328

Author(s):

Sara Habibi ◽

Arezou Jafari ◽

Zahra Fakhroueian

Keyword(s):

Enhanced Oil Recovery ◽

Oil Recovery ◽

Ionic Composition ◽

Water Flooding ◽

Wettability Alteration ◽

Core Flooding ◽

Sulfate Ions ◽

Smart Water ◽

Eor Processes ◽

Co Precipitation

Abstract Smart water flooding, as a popular method to change the wettability of carbonate rocks, is one of the interesting and challenging issues in reservoir engineering. In addition, the recent studies show that nanoparticles have a great potential for application in EOR processes. However, little research has been conducted on the use of smart water with nanoparticles in enhanced oil recovery. In this study, stability, contact angle and IFT measurements and multi-step core flooding tests were designed to investigate the effect of the ionic composition of smart water containing SO42− and Ca2+ ions in the presence of nanofluid on EOR processes. The amine/organosiloxane@Al2O3/SiO2 (AOAS) nanocomposite previously synthesized using co-precipitation-hydrothermal method has been used here. However, for the first time the application of this nanocomposite along with smart water has been studied in this research. Results show that by increasing the concentrations of calcium and sulfate ions in smart water, oil recovery is improved by 9% and 10%, respectively, compared to seawater. In addition, the use of smart water and nanofluids simultaneously is very effective on increasing oil recovery. Finally, the best performance was observed in smart water containing two times of sulfate ions concentration (SW2S) with nanofluids, showing increased efficiency of about 7.5%.

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Gas Pressure Cycling (GPC) and Solvent-Assisted Gas Pressure Cycling (SA-GPC) Enhanced Oil Recovery Processes in a Thin Heavy Oil Reservoir

Energies ◽

10.3390/en13195047 ◽

2020 ◽

Vol 13 (19) ◽

pp. 5047

Author(s):

Olusegun Ojumoola ◽

Hongze Ma ◽

Yongan Gu

Keyword(s):

Enhanced Oil Recovery ◽

Oil Recovery ◽

Heavy Oil ◽

Gas Pressure ◽

Oil Viscosity ◽

Step Size ◽

Foamy Oil ◽

Pressure Cycling ◽

Eor Processes ◽

Solvent Trapping

In this paper, gas pressure cycling (GPC) and solvent-assisted gas pressure cycling (SA-GPC) were developed as two new and effective enhanced oil recovery (EOR) processes. Eight coreflood tests were conducted by using a 2-D rectangular sandpacked physical model with a one or two-well configuration. More specifically, two cyclic solvent injection (CSI), three GPC, and three SA-GPC tests were conducted after the primary production, whose pressure was declined in steps from Pi = 3.0 MPa to Pf = 0.2 MPa. It was found that the CSI tests had poor performances because of the known CSI technical shortcomings and an additional technical issue of solvent trapping found in this study. Quick heavy oil viscosity regainment resulted in the solvent-trapping zone. In contrast, C3H8-GPC test at a pressure depletion step size of ∆PEOR = 0.5 MPa and C3H8-SA-CO2-GPC test at ∆PEOR = 1.0 MPa had the highest total heavy oil recovery factors (RFs) of 41.9% and 36.6% of the original oil-in-place (OOIP) among the two respective series of GPC and SA-GPC tests. The better performances of these two tests than C3H8- or CO2-CSI test were attributed to the effective displacement of the foamy oil toward the producer in the two-well configuration. Thus the back-and-forth movements of the foamy oil in CSI test in the one-well configuration were eliminated in these GPC and SA-GPC tests. Furthermore, C3H8-GPC test outperformed C3H8-SA-CO2-GPC test in terms of the heavy oil RF and cumulative gas-oil ratio (cGOR) because of the formation of stronger foamy-oil flow and the absence of CO2, which reduced the solubility of C3H8 in the heavy oil in the latter test. In summary, different solvent-based EOR processes were ranked based on the heavy oil RFs as follows: C3H8-GPC > C3H8-SA-CO2-GPC > CO2-GPC > C3H8-CSI > CO2-CSI.

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A study of downhole electromagnetic sources for mapping enhanced oil recovery processes

Geophysics ◽

10.1190/1.1443614 ◽

1994 ◽

Vol 59 (4) ◽

pp. 534-545 ◽

Cited By ~ 4

Author(s):

Gregory A. Newman

Keyword(s):

Enhanced Oil Recovery ◽

Oil Recovery ◽

Magnetic Dipoles ◽

Instrumental Noise ◽

Recovery Processes ◽

Before And After ◽

Order Of Magnitude ◽

Electric Dipoles ◽

Eor Processes ◽

Electric Source

An evaluation of downhole electromagnetic (EM) sources has been made for mapping 3-D enhanced oil recovery (EOR) processes. Two types of sources considered were vertical magnetic dipoles and vertical to near‐vertical electric dipoles and bipoles. These sources were used to produce magnetic field responses expected of EOR processes for crosswell configurations. A borehole‐to‐surface configuration was also studied for the downhole electric source, since this configuration can be highly sensitive to shallow 3-D EOR targets. For the crosswell arrays, the criteria used to evaluate the sources were the magnitudes of the observed signals with and without the process and the amount these signals change because of a migrating process. Instrumental noise was considered in the evaluation. Findings show that either electric or magnetic sources can produce truly significant changes in the fields, provided the fields before and after the initiation of the process are compared. An order of magnitude change in the fields has been demonstrated. The key to measuring such changes is to use the highest frequency possible. This frequency will be limited by instrumental noise. A migrating process did not produce field changes that are as large as those observed with and without the process. Nevertheless, model simulations showed that changes in the fields caused by the migrating processes are significant and measurable. Calculated responses of a shallow process at the surface showed that they were extremely sensitive to small deviations in the orientation of the downhole electric source. Quantitative interpretation should proceed only with techniques that explicitly consider the source orientation.

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A Novel Surfactant–Polymer/Alkaline–Surfactant–Polymer Formulation for Enhanced Oil Recovery (EOR) Processes

Energy & Fuels ◽

10.1021/acs.energyfuels.9b02275 ◽

2020 ◽

Vol 34 (2) ◽

pp. 1230-1239 ◽

Cited By ~ 1

Author(s):

Geraldo A. R. Ramos ◽

Lateef T. Akanji ◽

Waheed Afzal

Keyword(s):

Enhanced Oil Recovery ◽

Oil Recovery ◽

Eor Processes ◽

Alkaline Surfactant Polymer

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Performance Quantification of Enhanced Oil Recovery Methods in Fractured Reservoirs

Energies ◽

10.3390/en14164739 ◽

2021 ◽

Vol 14 (16) ◽

pp. 4739

Author(s):

Riyaz Kharrat ◽

Mehdi Zallaghi ◽

Holger Ott

Keyword(s):

Enhanced Oil Recovery ◽

Oil Recovery ◽

Driving Forces ◽

Fractured Reservoirs ◽

Gas Injection ◽

Capillary Forces ◽

Dimensionless Numbers ◽

Water Alternating Gas ◽

Eor Processes ◽

Wag Injection

The enhanced oil recovery mechanisms in fractured reservoirs are complex and not fully understood. It is technically challenging to quantify the related driving forces and their interaction in the matrix and fractures medium. Gravity and capillary forces play a leading role in the recovery process of fractured reservoirs. This study aims to quantify the performance of EOR methods in fractured reservoirs using dimensionless numbers. A systematic approach consisting of the design of experiments, simulations, and proxy-based optimization was used in this work. The effect of driving forces on oil recovery for water injection and several EOR processes such as gas injection, foam injection, water-alternating gas (WAG) injection, and foam-assisted water-alternating gas (FAWAG) injection was analyzed using dimensionless numbers and a surface response model. The results show that equilibrium between gravitational and viscous forces in fracture and capillary and gravity forces in matrix blocks determines oil recovery performance during EOR in fractured reservoirs. When capillary forces are dominant in gas injection, fluid exchange between fracture and matrix is low; consequently, the oil recovery is low. In foam-assisted water-alternating gas injection, gravity and capillary forces are in equilibrium conditions as several mechanisms are involved. The capillary forces dominate the water cycle, while gravitational forces govern the gas cycle due to the foam enhancement properties, which results in the highest oil recovery factor. Based on the performed sensitivity analysis of matrix–fracture interaction on the performance of the EOR processes, the foam and FAWAG injection methods were found to be more sensitive to permeability contrast, density, and matrix block highs than WAG injection.

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Chemical Enhanced Oil Recovery and Nanotechnology: Effects of Silica-Based Nanofluids on Low-Salinity Water Flooding and Enhanced Oil Recovery Processes in Oil-Wet and Water-Wet Reservoirs

10.5194/egusphere-egu21-13079 ◽

2021 ◽

Author(s):

Christophe Darnault ◽

Bruce Phibbs ◽

Casey McCarroll ◽

Brightin Blanton

Keyword(s):

Crude Oil ◽

Enhanced Oil Recovery ◽

Oil Recovery ◽

Water Flooding ◽

Light Crude Oil ◽

Low Salinity ◽

Low Salinity Water ◽

Reservoir Systems ◽

Salinity Water ◽

Eor Processes

<p>Advances in the field of nanoscience and nanotechnology have resulted in the development of engineered nanoparticles, with unique physico-chemical properties, and their applications to all the sectors of industry, including the petroleum industry. This presentation will discuss several advances and applications of silica-based nanofluids in chemical enhanced oil recovery (EOR) processes related to interfacial phenomena in multiphase systems and physics of multiphase flow in porous media, and in particular the oil recovery characteristics resulting from nanofluids based low-salinity water flooding and chemical EOR processes. Laboratory experiments were carried out using homogeneous sandpack columns simulating oil-wet and water-wet reservoirs. To simulate oil-wet reservoirs, the sandpack columns were saturated with a light crude oil (West Texas Intermediate) at first. While in the case of the simulated water-wet reservoirs, these reservoirs were made by saturating the sandpack columns initially with a 1.0 wt% brine (NaCl) and then followed by an injection of the light crude oil. The subsequent oil-saturated (oil-wet system) and oil-brine mixture (water-wet system) within the sandpack columns were then subject to water flooding (non-sequenced recovery) or EOR processes (sequenced recovery) utilizing brine and/or surfactant as controls as well as low (0.01 wt%) and high (0.1 wt%) silica-based nanofluids. When compared with the high concentration of silica-based nanofluid, the low silica-based nanofluid concentration produced low fractional and cumulative oil recovery results in the water flooding process of oil recovery for both oil-wet and water-wet reservoir systems; however, the low silica-based nanofluid concentration was found to be the most effective with EOR process for both oil-wet and water-wet reservoir systems. Our findings permit to choose optimal concentrations of silica nanoparticles to be employed for either water flooding or EOR processes in order to increase the oil extraction efficiency.</p>

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Enhanced Oil Recovery Pilot Testing Best Practices

SPE Reservoir Evaluation & Engineering ◽

10.2118/118055-pa ◽

2010 ◽

Vol 13 (01) ◽

pp. 143-154 ◽

Cited By ~ 18

Author(s):

G.F.. F. Teletzke ◽

R.C.. C. Wattenbarger ◽

J.R.. R. Wilkinson

Keyword(s):

Best Practices ◽

Enhanced Oil Recovery ◽

Oil Recovery ◽

Large Scale ◽

Full Range ◽

Mobility Control ◽

Small Scale ◽

Pilot Testing ◽

Advantages And Disadvantages ◽

Eor Processes

Summary Enhanced-oil-recovery (EOR) implementation is complex, and successful applications need to be tailored to each specific reservoir. Therefore, a systematic staged evaluation and development process is required to screen, evaluate, pilot test, and apply EOR processes for particular applications. Pilot testing can play a key role in this process. Before field testing, pilot objectives need to be clearly defined and well spacing, pattern configuration, and injectant volumes determined. This paper outlines a staged approach to EOR evaluation and focuses specifically on pilot testing best practices. These best practices were derived from ExxonMobil's extensive piloting experience, which includes more than 50 field pilot tests covering the full range of EOR processes. Topics covered include: (1) determining whether a pilot is needed and defining pilot objectives, (2) considerations for successful pilot design, (3) types of pilots and their advantages and disadvantages, (4) tools and techniques for assessment of key reservoir mechanisms, and (5) minimizing uncertainty in pilot interpretation. Key issues that are often addressed by pilots are discussed, including areal sweep and conformance, gravity override, viscous fingering, and loss of mobility control. Also included are aspects of instrumentation and measurements in pilot injection, production, and monitoring wells. Several ExxonMobil piloting examples are used to illustrate the best practices, including a single-well injectivity test, an unconfined pilot with observation wells, a small-scale confined pilot, and a large-scale multipattern pilot.

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