Visualizing and Quantifying Generation, Propagation, and Sweep of Nanocellulose-Strengthened Carbon Dioxide Foam in a Complex 2D Heterogeneous Fracture Network Model

Summary There exist two main issues hampering the wide application and development of carbon dioxide (CO2) foam in conformance improvement and CO2 mobility reduction in fractured systems: (1) instability of foam film under reservoir conditions and (2) uncertainties of foam flow in complex fractures. To address these two issues, we previously developed a series of nanocellulose-strengthened CO2 foam (referred to as NCF-st-CO2 foam), while the primary goal of this work is to thoroughly elucidate generation, propagation, and sweep of NCF-st-CO2 foam in a visual 2D heterogeneous fracture network model. NCF-st-CO2 foam outperformed CO2 foam in reducing gas mobility during either coinjection (COI) or surfactant-alternating-gas (SAG) injection, and the threshold foam quality was approximately 0.67. Foam creation was increased with the total superficial velocity for CO2 foam and almost stayed constant for NCF-st-CO2 foam in fractures during COI. For SAG, large surfactant slug could prevent CO2 from early breakthrough and facilitate foaming in situ. The improved sweep efficiency induced by NCF-st-CO2 foam occurred near the producer for both COI and SAG. Film division and behind mainly led to foam generation in the fracture model. Gravity segregation and override was insignificant during COI but became noticeable during SAG, which caused the sweep efficiency decrease by 3 to 9%. Owing to the enhanced film, NCF-st-CO2 foam enabled mitigation of the gravitational effect, especially around the producer.

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Direct Visualization and Quantification of NCF-Strengthened CO2 Foam Generation, Propagation and Sweep in a 2D Heterogeneous Fracture Network Model

10.2118/206011-ms ◽

2021 ◽

Author(s):

Bing Wei ◽

Qiong Yang ◽

Runxue Mao ◽

Qingtao Tian ◽

Dianlin Wang ◽

...

Keyword(s):

Surfactant Solution ◽

Gravitational Effect ◽

Fracture Network ◽

Co2 Injection ◽

Sweep Efficiency ◽

Foam Generation ◽

Co2 Foam ◽

Fracture Systems ◽

Reservoir Conditions ◽

Reduction Of Co2

Abstract CO2 foam holds promising potential for conformance improvement and mobility reduction of CO2 injection in fractured systems. However, there still exists two main issues hampering its wide application and development, 1. Instability of CO2 foam lamellae under reservoir conditions, and 2. Uncertainties of foam flow in fracture systems. To address these two issues, we previously developed a series of functional nanocellulose materials to stabilize the CO2 foam (referred to NCF-st-CO2 foam), while the primary goal of this paper is to thoroughly elucidate foam generation, propagation and sweep of NCF-st-CO2 foam in fractured systems by using a self-designed visual heterogeneous fracture network. We found that NCF-st-CO2 foam produced noticeably greater pressure drop (ΔP) than CO2 foam during either co-injection (COI) or surfactant solution-alternating-gas (SAG) injection, and the threshold foam quality (fg*) was approximately 0.67. Foam generation was increased with total flow rate for CO2 foam and stayed constant for NCF-st-CO2 foam in fracture during COI. CO2 breakthrough occurred at high flow rates (>8 cm3/min). For SAG, large surfactant slug could prevent CO2 from early breakthrough and facilitate foaming in-situ. The increase in sweep efficiency by NCF-st-CO2 foam was observed near the producer for both COI and WAG, which was attributed to its better foaming capacity. Film division and behind mainly led to foam generation in the fracture model. Gravity segregation and override was insignificant during COI but became noticeable during SAG, which caused the sweep efficiency decreased by 3~9% at 1.0 fracture volume (FV) injected. Due to the enhanced foam film, the NCF-st-CO2 foam was able to mitigate gravitational effect, especially in the vicinity of producer.

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Mobility of Ethomeen C12 and Carbon Dioxide (CO2) Foam at High Temperature/High Salinity and in Carbonate Cores

SPE Journal ◽

10.2118/179726-pa ◽

2016 ◽

Vol 21 (04) ◽

pp. 1151-1163 ◽

Cited By ~ 44

Author(s):

Leyu Cui ◽

Kun Ma ◽

Maura Puerto ◽

Ahmed A. Abdala ◽

Ivan Tanakov ◽

...

Keyword(s):

Carbon Dioxide ◽

High Temperature ◽

High Salinity ◽

Local Equilibrium ◽

Co2 Flooding ◽

Sweep Efficiency ◽

Co2 Foam ◽

Foam Model ◽

Wide Range ◽

Carbon Dioxide Co2

Summary The low viscosity and density of carbon dioxide (CO2) usually result in the poor sweep efficiency in CO2-flooding processes, especially in heterogeneous formations. Foam is a promising method to control the mobility and thus reduce the CO2 bypass because of the gravity override and heterogeneity of formations. A switchable surfactant, Ethomeen C12, has been reported as an effective CO2-foaming agent in a sandpack with low adsorption on pure-carbonate minerals. Here, the low mobility of Ethomeen C12/CO2 foam at high temperature (120 °C), high pressure (3,400 psi), and high salinity [22 wt% of total dissolved solids (TDS)] was demonstrated in Silurian dolomite cores and in a wide range of foam qualities. The influence of various parameters, including aqueous solubility, thermal and chemical stability, flow rate, foam quality, salinity, temperature, and minimum-pressure gradient (MPG), on CO2 foam was discussed. A local-equilibrium foam model, the dry-out foam model, was used to fit the experimental data for reservoir simulation.

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Enhanced Experimental Carbon Dioxide Sweep Using Surface Coated Silica Nanoparticles as a Foaming Agent

10.2118/206278-ms ◽

2021 ◽

Author(s):

Ahmad Alfakher ◽

David A. DiCarlo

Keyword(s):

Carbon Dioxide ◽

Silica Nanoparticles ◽

Oil Recovery ◽

Graphical Representation ◽

Co2 Flooding ◽

Sweep Efficiency ◽

Foaming Agent ◽

The Core ◽

Co2 Foam

Abstract Solvent flooding is a well-established method of enhanced oil recovery (EOR), with carbon dioxide (CO2) being the most-often used solvent. As CO2 is both less viscous and less dense than the fluids it displaces, the displacement suffers from poor sweep efficiency caused by an unfavorable mobility ratio and unfavorable gravity number. Creating in-situ CO2 foam improves the sweep efficiency of CO2 floods. Another application is the injection of CO2 foam into saline aquifers for carbon capture and storage (CCS). The goal of the core flood experiments in this paper was to study the effectiveness of surface coated silica nanoparticles as an in-situ CO2 foaming agent. In each experiment, the pressure drop was measured across five separate sections in the core, as well as along the whole core. In addition, the saturation distribution in the core was calculated periodically using computed tomography (CT) scanning measurements. The experiments consisted of vertical core floods where liquid CO2 displaced brine from the top to the bottom of the core. A flood with surface coated silica nanoparticles suspended in the brine is performed in the same core and at the same conditions to a flood with no nanoparticles, and results from these floods are compared. In these experiments, breakthrough occurred 45% later with foamed CO2, and the final CO2 saturation was also 45% greater than with the unfoamed CO2. The study shows how nanoparticles stabilize the CO2 front. The results provide quantitative information on, as well as a graphical representation of, the behavior of the CO2 foam front as it advances through the core. This data can be used to upscale the behavior observed and properties calculated from the core-scale to the reservoir-scale to improve field applications of CO2 flooding.

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The Effect of Phase Equilibria on the CO2 Displacement Mechanism

Society of Petroleum Engineers Journal ◽

10.2118/7061-pa ◽

1979 ◽

Vol 19 (04) ◽

pp. 242-252 ◽

Cited By ~ 38

Author(s):

R.S. Metcalfe ◽

Lyman Yarborough

Keyword(s):

Carbon Dioxide ◽

Phase Equilibria ◽

Enhanced Oil Recovery ◽

Oil Recovery ◽

Miscible Displacement ◽

Co2 Flooding ◽

Recovery Method ◽

Two Fluids ◽

Reservoir Conditions

Abstract Carbon dioxide flooding under miscible conditions is being developed as a major process for enhanced oil recovery. This paper presents results of research studies to increase our understanding of the multiple-contact miscible displacement mechanism for CO2 flooding. Carbon dioxide displacements of three synthetic oils of increasing complexity (increasing number of hydrocarbon components) are described. The paper concentrates on results of laboratory flow studies, but uses results of phase-equilibria and numerical studies to support the conclusions.Results from studies with synthetic oils show that at least two multiple-contact miscible mechanisms, vaporization and condensation, can be identified and that the phase-equilibria data can be used as a basis for describing the mechanism. The phase-equilibria change with varying reservoir conditions, and the flow studies show that the miscible mechanism depends on the phase-equilibria behavior. Qualitative predictions with mathematical models support our conclusions.Phase-equilibria data with naturally occurring oils suggest the two mechanisms (vaporization and condensation) are relevant to CO2 displacements at reservoir conditions and are a basis for specifying the controlling mechanisms. Introduction Miscible-displacement processes, which rely on multiple contacts of injected gas and reservoir oil to develop an in-situ solvent, generally have been recognized by the petroleum industry as an important enhanced oil-recovery method. More recently, CO2 flooding has advanced to the position (in the U.S.) of being the most economically attractive of the multiple-contact miscibility (MCM) processes. Several projects have been or are currently being conducted either to study or use CO2 as an enhanced oil-recovery method. It has been demonstrated convincingly by Holm and others that CO2 can recover oil from laboratory systems and therefore from the swept zone of petroleum reservoirs using miscible displacement. However, several contradictions seem to exist in published results.. These authors attempt to establish the mechanism(s) through which CO2 and oil form a miscible solvent in situ. (The solvent thus produced is capable of performing as though the two fluids were miscible when performing as though the two fluids were miscible when injected.) In addition, little experimental work has been published to provide support for the mechanisms of multiple-contact miscibility, as originally discussed by Hutchinson and Braun.One can reasonably assume that the miscible CO2 process will be related directly to phase equilibria process will be related directly to phase equilibria because it involves intimate contact of gases and liquids. However, no data have been published to indicate that the mechanism for miscibility development may differ for varying phase-equilibria conditions.This paper presents the results of both flow and phase-equilibria studies performed to determine the phase-equilibria studies performed to determine the mechanism(s) of CO2 multiple-contact miscibility. These flow studies used CO2 to displace three multicomponent hydrocarbon mixtures under first-contact miscible, multiple-contact miscible, and immiscible conditions. Results are presented to support the vaporization mechanism as described by Hutchinson and Braun, and also to show that more than one mechanism is possible with CO2 displacements. The reason for the latter is found in the results of phase-equilibria studies. SPEJ P. 242

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Construction of 3D Discrete Fracture Network Model using Structural and Hydrogeological Data

10.5194/egusphere-egu2020-16033 ◽

2020 ◽

Author(s):

Mohammadreza Jalali ◽

Zhen Fang ◽

Pooya Hamdi

Keyword(s):

Rock Mass ◽

Network Model ◽

Fracture Network ◽

Crystalline Rock ◽

Discrete Fracture Network ◽

Seismic Survey ◽

Discrete Fracture ◽

Dfn Model ◽

Hydrogeological Data

The presence of fractures and discontinuities in the intact rock affects the hydraulic, thermal, chemical and mechanical behavior of the underground structures. Various techniques have been developed to provide information on the spatial distribution of these complex features. LIDAR, for instance, could provide a 2D fracture network model of the outcrop, Geophysical borehole logs such as OPTV and ATV can be used to investigate 1D geometrical data (i.e. dip and dip direction, aperture) of the intersected fractures, and seismic survey can mainly offer a large structure distribution of the deep structures. The ability to combine all the existing data collected from various resources and different scales to construct a 3D discrete fracture network (DFN) model of the rock mass allows to adequately represent the physical behavior of the interested subsurface structure.In this study, an effort on the construction of such a 3D DFN model is carried out via combination of various structural and hydrogeological data collected in fractured crystalline rock. During the pre-characterization phase of the In-situ Stimulation and Circulation (ISC) experiment [Amann et al., 2018] at the Grimsel Test Site (GTS) in central Switzerland, a comprehensive characterization campaign was carried out to better understand the hydromechanical characteristics of the existing structures. The collected multiscale and multidisciplinary data such as OPTV, ATV, hydraulic packer testing and solute tracer tests [Jalali et al., 2018; Krietsch et al., 2018] are combined, analyzed and interpreted to form a combined stochastic and deterministic DFN model using the FracMan software [Golder Associates, 2017]. For further validation of the model, the results from in-situ hydraulic tests are used to compare the simulated and measured hydraulic responses, allowing to evaluate whether the simulated model could reasonably represent the characteristics of the fracture network in the ISC experiment.&#160;References<ul><li>Amann, F., Gischig, V., Evans, K., Doetsch, J., Jalali, M., Valley, B., Krietsch, H., Dutler, N., Villiger, L., Brixel, B., Klepikova, M., Kittil&#228;, A., Madonna, C., Wiemer, S., Saar, M.O., Loew, S., Driesner, T., Maurer, H., Giardini, D., 2018. The seismo-hydromechanical behavior during deep geothermal reservoir stimulations: open questions tackled in a decameter-scale in situ stimulation experiment. Solid Earth 9, 115&#8211;137.</li> <li>Golder Associates, 2017. FracMan User Documentation.&#160; Golder Associates Inc, Redmond WA.</li> <li>Krietsch, H., Doetsch, J., Dutler, N., Jalali, M., Gischig, V., Loew, S., Amann, F., 2018. Comprehensive geological dataset describing a crystalline rock mass for hydraulic stimulation experiments. Scientific Data 5, 180269.</li> <li>Jalali, M., Klepikova, M., Doetsch, J., Krietsch, H., Brixel, B., Dutler, N., Gischig, V., Amann, F., 2018. A Multi-Scale Approach to Identify and Characterize the Preferential Flow Paths of a Fractured Crystalline Rock. Presented at the 2nd International Discrete Fracture Network Engineering Conference, American Rock Mechanics Association.</li> </ul>

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Pictet—Spengler Reactions in Multiphasic Supercritical Carbon Dioxide/CO2-Expanded Liquid Media. In situ Generation of Carbamates as a Strategy for Reactions of Amines in Supercritical Carbon Dioxide.

ChemInform ◽

10.1002/chin.200602146 ◽

2006 ◽

Vol 37 (2) ◽

Author(s):

Joshua R. Dunetz ◽

Rocco P. Ciccolini ◽

Morgan Froeling ◽

Scott M. Paap ◽

Andrew J. Allen ◽

...

Keyword(s):

Carbon Dioxide ◽

Supercritical Carbon Dioxide ◽

Liquid Media ◽

In Situ Generation ◽

Carbon Dioxide Co2 ◽

Supercritical Carbon

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A Fiber-Integrated CRDS Sensor for In-Situ Measurement of Dissolved Carbon Dioxide in Seawater

Sensors ◽

10.3390/s21196436 ◽

2021 ◽

Vol 21 (19) ◽

pp. 6436

Author(s):

Mai Hu ◽

Bing Chen ◽

Lu Yao ◽

Chenguang Yang ◽

Xiang Chen ◽

...

Keyword(s):

Carbon Dioxide ◽

Equilibrium Condition ◽

Co2 Concentration ◽

Scientific Data ◽

In Situ Measurement ◽

Integrated Sensor ◽

Dissolved Carbon ◽

Low Efficiency ◽

Carbon Dioxide Co2

Research on carbon dioxide (CO2) geological and biogeochemical cycles in the ocean is important to support the geoscience study. Continuous in-situ measurement of dissolved CO2 is critically needed. However, the time and spatial resolution are being restricted due to the challenges of very high submarine pressure and quite low efficiency in water-gas separation, which, therefore, are emerging the main barriers to deep sea investigation. We develop a fiber-integrated sensor based on cavity ring-down spectroscopy for in-situ CO2 measurement. Furthermore, a fast concentration retrieval model using exponential fit is proposed at non-equilibrium condition. The in-situ dissolved CO2 measurement achieves 10 times faster than conventional methods, where an equilibrium condition is needed. As a proof of principle, near-coast in-situ CO2 measurement was implemented in Sanya City, Haina, China, obtaining an effective dissolved CO2 concentration of ~950 ppm. The experimental results prove the feasibly for fast dissolved gas measurement, which would benefit the ocean investigation with more detailed scientific data.

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Supercritical CO2-Foam Screening and Performance Evaluation for CO2 Storage Improvement in Sandstone and Carbonate Formations

10.2118/208141-ms ◽

2021 ◽

Author(s):

Ying Yu ◽

Alvinda Sri Hanamertani ◽

Shehzad Ahmed ◽

Zunsheng Jiao ◽

Jonathan Fred McLaughlin ◽

...

Keyword(s):

Surface Tension ◽

Storage Capacity ◽

Co2 Storage ◽

Mobility Control ◽

Zwitterionic Surfactant ◽

Water Displacement ◽

Sweep Efficiency ◽

Foam Generation ◽

Co2 Foam ◽

Reservoir Conditions

Abstract Injecting carbon dioxide (CO2) as foam during enhanced oil recovery (EOR) can improve injectate mobility and increase sweep efficiency. Integrating CO2-foam techniques with carbon capture, utilization and storage (CCUS) operations is of recent interest, as the mobility control and sweep efficiency increases seen in EOR could also benefit CO2 storage during CCUS. In this study, a variety of different charge, hydrocarbon chain length, head group surfactants were evaluated by surface tension, bulk and dynamic CO2-foam performance assessments for CCUS. The optimal foam candidate was expected to provide satisfying mobility control effects under reservoir conditions, leading to an improved water displacement efficiency during CO2-foam flooding that favors a more significant CO2 storage potential. All tested surfactants were able to lower their surface tensions against scCO2 by 4-5 times, enlarging the surface area of solution/gas contact; therefore, more CO2 could be trapped in the foam system. A zwitterionic surfactant was found to have slightly higher surface tension against CO2 while exhibiting the highest foaming ability and the most prolonged foam stability with a relatively slower drainage rate among all tested surfactants. The dynamic performance of scCO2-foam stabilized by this zwitterionic surfactant was also evaluated in sandstone and carbonate cores at 13.79 MPa and 90°C. The results show that the mobility control development in carbonate core was relatively slower, suggesting a gradual foam generation process attributed to the higher permeability than the case in sandstone core. A more significant cumulative CO2 storage potential improvement, quantified based on the water production, was recorded in sandstone (53%) over the carbonate (47%). Overall, the selected foam has successfully developed CO2 mobility control and improved water displacement in the occurrence of in-situ foam generation, hence promoting the storage capacity for the injected CO2. This work has optimized the foaming agent selection method at the actual reservoir conditions and evaluated the scCO2-foam performance in establishing high flow resistance and improving the CO2 storage capacity, which benefits integrated CCUS studies or projects utilizing CO2-foam techniques.

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Flow Characteristics of Foam in Fractures and Prediction of Preferred Paths

10.1115/omae2021-62765 ◽

2021 ◽

Author(s):

Zhengxiao Xu ◽

Zhaomin Li ◽

Binfei Li ◽

Danqi Chen ◽

Xianghui Zeng ◽

...

Keyword(s):

Network Model ◽

Fractured Reservoirs ◽

Flow Characteristics ◽

Weighted Graph ◽

Fracture Network ◽

Dijkstra’S Algorithm ◽

Sweep Efficiency ◽

Foam Flow ◽

Complex Fracture ◽

Dijkstra's Algorithm

Abstract Foam is widely used in fractured reservoirs. The flow characteristics in complex fracture networks are still unclear, and there are few numerical simulations of foam fluid flow in fractures. In this study, a variety of combined visual fracture models were used to observe the flow characteristics of foam in the fracture. Firstly, based on the parallel fracture model, the foam flow characteristics under different fracture depths were explored, and then based on the complex fracture network model, the foam flow path and sweep efficiency are evaluated. Finally, the Dijkstra’s algorithm was used to determine the weighted graph of the fracture network nodes, and the preferred flow paths of the foam were predicted. The results show that when foam flows in parallel fractures with different depths, it preferentially flows in high permeability (100 μm) fractures, and there is gas trapping in low permeability (50 μm) fractures. In the irregular fracture network model, the sweep efficiency of the foam fluid is greatly affected by the foam quality, and the sweep volume is the widest when the foam quality is about 90%. The simulation results based on the Dijkstra’s algorithm can be fitted to the experimental results to a certain extent. By controlling the number of preferred paths and the weight of nodes, the plugging and regulating performance of the foam are characterized. These findings reflect the necessity of considering fractures when foam flows in reservoirs, and provide a certain experimental basis and theoretical guidance for the development of fractured reservoirs.

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