Does Miscibility Alone Predict the Success of WAG Projects? Key Issues in Miscible HC-WAG Injection

2021 ◽  
Author(s):  
Mohamad Yousef Alklih ◽  
Nidhal Mohamed Aljneibi ◽  
Karem Alejandra Khan ◽  
Melike Dilsiz
Keyword(s):  
Oil Recovery ◽  
Flow Behavior ◽  
Low Frequency ◽  
Lessons Learned ◽  
Water Flooding ◽  
Reservoir Properties ◽  
Full Field ◽  
Incremental Oil Recovery ◽  
Gas Market ◽  
Wag Injection

Abstract Miscible HC-WAG injection is a globally implemented EOR method and seems robust in so many cases. Some of the largest HC-WAG projects are found in major carbonate oil reservoirs in the Middle-East, with miscibility being the first measure to expect the success of a HC-WAG injection. Yet, several miscible injection projects reported disappointing outcomes and challenging implementation that reduces the economic attractiveness of the miscible processes. To date, there are still some arguments on the interpretation of laboratory and field data and predictive modeling. For a miscible flood, to be an efficient process for a given reservoir, several conditions must be satisfied; given that the incremental oil recovery is largely dependent on reservoir properties and fluid characteristic. Experiences gained from a miscible rich HC-WAG project in Abu Dhabi, implemented since 2006, indicate that an incremental recovery of 10% of the original oil in place can be achieved, compared to water flooding. However, experiences also show that several complexities are being faced, including but not limited to, issues of water injectivity in the mixed wettability nature of the reservoir, achieving miscibility conditions full field, maintaining VRR and corresponding flow behavior, suitability of monitoring strategy, UTC optimization efforts by gas curtailment and most importantly challenges of modeling the miscibility behavior across the reservoir. A number of mitigation plans and actions are put in place to chase the positive impacts of enhanced oil recovery by HC-WAG injection. If gas injection is controlled for gravity and dissolution along with proper understanding on the limitations of WAG, then miscible flood will lead to excellent results in the field. The low frequency of certain reservoir monitoring activities, hence less available data for assessment and modeling, can severely bound the benefits of HC-WAG and make it more difficult to justify the injection of gas, particularly in those days when domestic gas market arises. This work aims to discuss the lessons learned from the ongoing development of HC-WAG and attempts to comprehend miscible flood assessment methods.

scholarly journals Pore-Scale Simulation of Particle Flooding for Enhancing Oil Recovery

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2305
Author(s):  
Xiangbin Liu ◽  
Le Wang ◽  
Jun Wang ◽  
Junwei Su
Keyword(s):  
Oil Recovery ◽  
Flow Behavior ◽  
Ct Scanning ◽  
Water Flooding ◽  
Pore Scale ◽  
Simulation Techniques ◽  
Three Phase ◽  
Remaining Oil ◽  
Three Phase Flow ◽  
Displacement Force

The particles, water and oil three-phase flow behaviors at the pore scale is significant to clarify the dynamic mechanism in the particle flooding process. In this work, a newly developed direct numerical simulation techniques, i.e., VOF-FDM-DEM method is employed to perform the simulation of several different particle flooding processes after water flooding, which are carried out with a porous structure obtained by CT scanning of a real rock. The study on the distribution of remaining oil and the displacement process of viscoelastic particles shows that the capillary barrier near the location with the abrupt change of pore radius is the main reason for the formation of remaining oil. There is a dynamic threshold in the process of producing remaining oil. Only when the displacement force exceeds this threshold, the remaining oil can be produced. The flow behavior of particle–oil–water under three different flooding modes, i.e., continuous injection, alternate injection and slug injection, is studied. It is found that the particle size and the injection mode have an important influence on the fluid flow. On this basis, the flow behavior, pressure characteristics and recovery efficiency of the three injection modes are compared. It is found that by injecting two kinds of fluids with different resistance increasing ability into the pores, they can enter into different pore channels, resulting in the imbalance of the force on the remaining oil interface and formation of different resistance between the channels, which can realize the rapid recovery of the remaining oil.

scholarly journals Development of an analytical model to predict oil reservoirs performance using mechanical waves propagation

2021 ◽  
Author(s):  
Hesham A. Abu Zaid ◽  
◽  
Sherif A. Akl ◽  
Mahmoud Abu El Ela ◽  
Ahmed El-Banbi ◽  
...  
Keyword(s):  
Oil Recovery ◽  
Field Measurements ◽  
Field Trials ◽  
Oil Field ◽  
Reservoir Properties ◽  
Actual Performance ◽  
Reservoir Performance ◽  
Mechanical Waves ◽  
Incremental Oil Recovery ◽  
Wave Induced

The mechanical waves have been used as an unconventional enhanced oil recovery technique. It has been tested in many laboratory experiments as well as several field trials. This paper presents a robust forecasting model that can be used as an effective tool to predict the reservoir performance while applying seismic EOR technique. This model is developed by extending the wave induced fluid flow theory to account for the change in the reservoir characteristics as a result of wave application. A MATLAB program was developed based on the modified theory. The wave’s intensity, pressure, and energy dissipation spatial distributions are calculated. The portion of energy converted into thermal energy in the reservoir is assessed. The changes in reservoir properties due to temperature and pressure changes are considered. The incremental oil recovery and reduction in water production as a result of wave application are then calculated. The developed model was validated against actual performance of Liaohe oil field. The model results show that the wave application increases oil production from 33 to 47 ton/day and decreases water-oil ratio from 68 to 48%, which is close to the field measurements. A parametric analysis is performed to identify the important parameters that affect reservoir performance under seismic EOR. In addition, the study determines the optimum ranges of reservoir properties where this technique is most beneficial.

Water-flooding Incremental Oil Recovery Study in Middle Miocene to Paleocene Reservoirs, Deep-Water Gulf of Mexico

2008 ◽  
Author(s):  
Bin Liu ◽  
Richard Brian Dessenberger ◽  
Ken McMillen ◽  
Joseph R. Lach ◽  
Mohan Gajanan Kelkar
Keyword(s):  
Gulf Of Mexico ◽  
Oil Recovery ◽  
Deep Water ◽  
Middle Miocene ◽  
Water Flooding ◽  
Recovery Study ◽  
Incremental Oil Recovery

scholarly journals Optimization Design of Injection Strategy for Surfactant-Polymer Flooding Process in Heterogeneous Reservoir under Low Oil Prices

Energies ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3789 ◽  
Author(s):  
He ◽  
Chen ◽  
Yu ◽  
Wen ◽  
Liu
Keyword(s):  
Oil Recovery ◽  
Oil Prices ◽  
Water Flooding ◽  
Fractional Flow ◽  
Simultaneous Injection ◽  
Oil Distribution ◽  
Remaining Oil ◽  
Remaining Oil Distribution ◽  
Incremental Oil Recovery ◽  
Injection Strategies

Surfactant–polymer (SP) flooding has significant potential to enhance oil recovery after water flooding in mature reservoirs. However, the economic benefit of the SP flooding process is unsatisfactory under low oil prices. Thus, it is necessary to reduce the chemical costs and improve SP flooding efficiency to make SP flooding more profitable. Our goal was to maximize the incremental oil recovery of the SP flooding process after water flooding by using the equal chemical consumption cost to ensure the economic viability of the SP flooding process. Thus, a systematic study was carried out to investigate the SP flooding process under different injection strategies by conducting parallel sand pack flooding experiments to optimize the SP flooding design. Then, the comparison of the remaining oil distribution after water flooding and SP flooding under different injection strategies was studied. The results demonstrate that the EOR efficiency of the SP flooding process under the alternating injection of polymer and surfactant–polymer (PASP) is higher than that of conventional simultaneous injection of surfactant and polymer. Moreover, as the alternating cycle increases, the incremental oil recovery increases. Based on the analysis of fractional flow, incremental oil recovery, and remaining oil distribution when compared with the conventional simultaneous injection of surfactant and polymer, the alternating injection of polymer and surfactant–polymer (PASP) showed better sweep efficiency improvement and recovered more remaining oil trapped in the low permeability zone. Thus, these findings could provide insights into designing the SP flooding process under low oil prices.

scholarly journals Experimental Study on the Physical Performance and Flow Behavior of Decorated Polyacrylamide for Enhanced Oil Recovery

Energies ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 562 ◽  
Author(s):  
Shuang Liang ◽  
Yikun Liu ◽  
Shaoquan Hu ◽  
Anqi Shen ◽  
Qiannan Yu ◽  
...  
Keyword(s):  
Interfacial Tension ◽  
Enhanced Oil Recovery ◽  
Oil Recovery ◽  
Flow Behavior ◽  
Polymer Flooding ◽  
Water Flooding ◽  
Displacement Effect ◽  
Microscale Model ◽  
Water Cut ◽  
Viscosity Stability

With the rapid growth of energy consumption, enhanced oil recovery (EOR) methods are continually emerging, the most effective and widely used was polymer flooding. However, the shortcomings were gradually exposed. A novel decorated polyacrylamide might be a better alternative than polymer. In this work, the molecular structure and the properties reflecting the viscosity of decorated polyacrylamide, interfacial tension, and emulsification were examined. In order to better understand the interactions between decorated polyacrylamide and oil as well as the displacement mechanism, the displacement experiment were conducted in the etched-glass microscale model. Moreover, the coreflooding comparison experiments between decorated polyacrylamide and polymer were performed to investigate the displacement effect. The statistical analysis showed that the decorated polyacrylamide has excellent characteristics of salt tolerance, viscosity stability, and viscosification like polymer. Besides, the ability to reduce the interfacial tension in order 10−1 and emulsification, which were more similar to surfactant. Therefore, the decorated polyacrylamide was a multifunctional polymer. The displacement process captured by camera illustrated that the decorated polyacrylamide flooded oil mainly by means of ‘pull and drag’, ‘entrainment’, and ‘bridging’, based on the mechanism of viscosifying, emulsifying, and viscoelasticity. The results of the coreflooding experiment indicated that the recovery of decorated polyacrylamide can be improved by approximately 11–16% after water flooding when the concentration was more than 800 mg/L, which was higher than that of conventional polymer flooding. It should be mentioned that a new injection mode of ‘concentration reduction multi-slug’ was first proposed, and it obtained an exciting result of increasing oil production and decreasing water-cut, the effect of conformance control was more significant.

The success story of Windalia waterflood optimisation through integrated asset management in a mature field

2011 ◽  
Vol 51 (2) ◽  
pp. 726
Author(s):  
Lina Hartanto ◽  
Wisnu Widjanarko ◽  
Diala Muna
Keyword(s):  
Oil Recovery ◽  
Asset Management ◽  
Produced Water ◽  
Lessons Learned ◽  
Full Potential ◽  
Success Story ◽  
Sweep Efficiency ◽  
Full Field ◽  
Injection Flow ◽  
Mature Field

Australia’s Barrow Island Windalia reservoir—the nation’s largest onshore waterflood—was developed in the late 1960s. The Barrow Island oilfield is Chevron Australia’s only mature waterflood, comprising more than 220 active injectors. The injectors pressurise and increase oil recovery from the geologically complex, low-permeable and heterogeneous Windalia Sand Member. To date it is estimated that the value of waterflooding has effectively reduced the field decline rate from approximately 18 % per annum to less than 2 %—adding millions of barrels in recovery and years on to productive field life. In September of 2008, the Windalia Waterflood achieved full field restitution. This involved the replacement and commissioning of glass-reinforced epoxy injection flow lines, a ring-main network and produced water re-injection facilities. Significant challenges were overcome in the process of realising the restitution’s full potential. Several waterflood optimisation activities have now been executed to achieve oil uplift and to capitalise on Chevron Australia’s investment. Compounded with restitution, the activities have successfully achieved the asset objective of arresting field production decline. This paper highlights the challenges encountered by the waterflood team, providing insights and lessons learned in the dynamic and holistic nature of waterflood management. It also highlights the interplay of considerations and what is crucial to achieving optimum sweep efficiency and pressurisation.

Lessons Learned From Energy Models: Iraq's South Rumaila Case Study

2008 ◽  
Vol 11 (04) ◽  
pp. 759-767 ◽  
Author(s):  
C. Shah Kabir ◽  
Nidhal I. Mohammed ◽  
Manoj K. Choudhary
Keyword(s):  
Finite Difference ◽  
History Matching ◽  
Flow Behavior ◽  
Finite Difference Methods ◽  
Water Injection ◽  
Material Balance ◽  
Reservoir Management ◽  
Lessons Learned ◽  
Full Field ◽  
Numeric Modeling

Summary Understanding reservoir behavior is the key to reservoir management. This study shows how energy modeling with rapid material-balance techniques, followed by numerical simulations with streamlines and finite-difference methods, aided understanding of reservoir-flow behavior. South Rumaila's long and elongated Zubair reservoir experiences uneven aquifer support from the western and eastern flanks. This uneven pressure support prompted injection in the weaker eastern flank to boost reservoir energy. We learned that aquifer influx provided nearly 95% of the reservoir's energy in its 50-year producing life, with water injection contributing less than 5% of the total energy supply. The west-to-east aquifer energy support is approximately 29:1, indicating the dominance of aquifer support in the west. Streamline simulations with a 663,000-cell model corroborated many of the findings learned during the material-balance phase of this study. Cursory adjustments to aquifer properties led to acceptable match with pulse-neutron capture or PNC-derived-time-lapse oil/water contact (OWC) surfaces. This global-matching approach speeded up the history-matching exercise in that performance of most wells was reproduced, without resorting to local adjustments of the cell properties. The history-matched model showed that the top layers contained the attic oil owing to lack of perforations. Lessons learned from this study include the idea that the material-balance work should precede any numerical flow-simulation study because it provides invaluable insights into reservoir-drive mechanisms and integrity of various input data, besides giving a rapid assessment of the reservoir's flow behavior. Credible material-balance work leaves very little room for adjustment of original hydrocarbons in place, which constitutes an excellent starting point for numerical models. Introduction Before the advent of widespread use of computers and numeric simulators, material-balance (MB) studies were the norm for reservoir management. In this context, Stewart et al. (1954), Irby et al. (1962), and McEwen (1962) presented useful studies. Most popular MB methods include those of Havlena and Odeh (1963), Campbell and Campbell (1978), and Tehrani (1985), among others. Pletcher (2002) provides a comprehensive review of the available MB techniques. In the modern era, classical MB studies seldom precede a full-field numeric modeling, presumably because MB is implicit in this approach. Nonetheless, we think valuable lessons can be learned from analytic MB studies at a fraction of time needed for detailed numeric modeling, preceded by geologic modeling. Of course, the value and amount of information derived from a multicell numeric model cannot be compared to a single-cell MB model. But, an analytic MB study can be an excellent precursor to any detailed 3D modeling effort. Although this point has been made by others (Dake 1994; Pletcher 2002), practice has, however, lagged conventional wisdom. In this paper, we attempt to show the value of a zero-dimensional MB study prior to doing detailed 3D numeric modeling, using both streamline and finite-difference methods. Streamline simulations speeded up the history-matching effort by a factor of three. However, we used the finite-difference approach in prediction runs for its greater flexibility in invoking various producing rules. Initially, the MB study provided key learnings about gross reservoir behavior very rapidly. In particular, energy contributions made by different drive mechanisms, such as uneven natural water influx and water injection, were of great interest for ongoing reservoir-management activities. Estimating in-place hydrocarbon volume and relative strength of the aquifer in the western and eastern flanks constituted key objectives of this study segment. Following the MB segment of the study, we pursued full-field match of historical data (pressure and OWC) with a streamline flow simulator to take advantage of rapid turnaround time. Thereafter, prediction runs were made with the finite-difference model to answer the ongoing water-injection question in the eastern flank of the reservoir. We learned that water injection should be turned off for improved sweep, leading to increased ultimate oil recovery. In addition, the numeric models identified the presence of remaining oil in the attic for future exploitation.

scholarly journals Flow Dynamics of Sulfate-Modified Water/Polymer Flooding in Micromodels with Modified Wettability

2020 ◽  
Vol 10 (9) ◽  
pp. 3239 ◽  
Author(s):  
Muhammad Tahir ◽  
Rafael E. Hincapie ◽  
Calvin L. Gaol ◽  
Stefanie Säfken ◽  
Leonhard Ganzer
Keyword(s):  
Oil Recovery ◽  
Flow Behavior ◽  
Water Flooding ◽  
Process Efficiency ◽  
Pore Scale ◽  
Low Salinity ◽  
Low Salinity Water ◽  
Salinity Water ◽  
Core Flood ◽  
Fluid Interaction

This work describes the flow behavior of the oil recovery obtained by the injection of sulfate-modified/low-salinity water in micromodels with different wettabilities. It provides a detailed microscopic visualization of the displacement taking place during modified water flooding at a pore-scale level, while evaluating the effect of wettability on oil recovery. A comprehensive workflow for the evaluation is proposed that includes fluid–fluid and rock–fluid interactions. The methods studied comprise flooding experiments with micromodels. Artificial and real structure water-wet micromodels are used to understand flow behavior and oil recovery. Subsequently, water-wet, complex-wet, and oil-wet micromodels help understand wettability and rock–fluid interaction. The effect of the sulfate content present in the brine is a key variable in this work. The results of micromodel experiments conducted in this work indicate that sulfate-modified water flooding performs better in mixed-wet/oil-wet (artificial structure) than in water-wet systems. This slightly differs from observations of core flood experiments, where oil-wet conditions provided better process efficiency. As an overall result, sulfate-modified water flooding recovered more oil than SSW injection in oil-wet and complex-wet systems compared to water-wet systems.

Heavy Oil Distribution and its Influence on Remaining Oil Distribution of G6 Block in Jinhu Depression

2014 ◽  
Vol 556-562 ◽  
pp. 937-939
Author(s):  
Xue Li ◽  
Jing Rui Xu ◽  
Jin Liang Zhang
Keyword(s):  
Oil Recovery ◽  
Heavy Oil ◽  
Water Flooding ◽  
Dynamic Resistance ◽  
Reservoir Properties ◽  
Oil Distribution ◽  
Geological Conditions ◽  
Remaining Oil ◽  
Remaining Oil Distribution ◽  
The Impact

Heavy oil, with the characteristics of high viscosity and large density, is the most important component of petroleum hydrocarbon energy. In reservoir exploration, its dynamic resistance not only reduces driven efficiency, but also brings much more exploration difficulty, so it is not feasible to exploit heavy oil with conventional methods. Previous studies have carried heavy oil research , but few have attempted to examine the impact of heavy oil on reservoir properties .In this paper, a detailed analysis of heavy oil distribution and remaining oil distribution of G6 block is performed. The conclusion are drawn: the local water flooding and local remaining oil selectively accumulation are caused by heavy oil through reducing water flooding efficiency; As to heavy oil recovery, appropriate exploration should be selected to reduce viscosity of heavy oil according to different geological conditions.

Sign in / Sign up

Export Citation Format

Share Document