Rock Permeability Research Articles

Geological data utilization in renewable energy mapping and volcanic region carbon storage feasibility

Geological data plays a crucial role in mapping renewable energy resources and assessing the feasibility of carbon storage in volcanic regions. This review explores the utilization of geological data in these areas, highlighting its significance and implications. Geological data is fundamental in mapping renewable energy resources, such as geothermal and hydroelectric energy. By analyzing geological structures, researchers can identify areas with high potential for these renewable energy sources. This mapping is essential for sustainable energy planning, as it allows policymakers to prioritize regions for renewable energy development based on geological suitability. Additionally, geological data is instrumental in assessing the feasibility of carbon storage in volcanic regions. Volcanic rocks have the potential to store carbon dioxide through mineral carbonation, a process where CO2 reacts with minerals to form stable carbonates. Geological data, including rock composition, porosity, and permeability, is used to evaluate the capacity of volcanic rocks to store carbon dioxide safely and effectively. The utilization of geological data in renewable energy mapping and volcanic region carbon storage feasibility has significant implications for sustainable energy development and climate change mitigation. By mapping renewable energy resources, countries can reduce their dependence on fossil fuels and transition to cleaner, more sustainable energy sources. Furthermore, assessing the feasibility of carbon storage in volcanic regions can help mitigate the impacts of climate change by sequestering CO2 emissions from industrial sources. In conclusion, geological data plays a crucial role in mapping renewable energy resources and assessing the feasibility of carbon storage in volcanic regions. By leveraging geological data, policymakers and researchers can make informed decisions about sustainable energy development and climate change mitigation.

Augmenting X-ray micro-CT data with MICP data for high resolution pore-scale simulations of flow properties of carbonate rocks

Pore-scale modeling is essential in understanding and predicting flow and transport properties of rocks. Generally, pore-scale modeling is dependent on imaging technologies such as Micro Computed Tomography (micro-CT), which provides visual confirmation into the pore microstructures of rocks at a representative scale. However, this technique is limited in the ability to provide high resolution images showing the pore-throats connecting pore bodies. Pore scale simulations of flow and transport properties of rocks are generally done on a single 3D pore microstructure image. As such, the simulated properties are only representative of the simulated pore-scale rock volume. These are the technological and computational limitations which we address here by using a stochastic pore-scale simulation approach. This approach consists of constructing hundreds of 3D pore microstructures of the same pore size distribution and overall porosity but different pore connectivity. The construction of the 3D pore microstructures incorporates the use of Mercury Injection Capillary Pressure (MICP) data to account for pore throat size distribution, and micro-CT images to account for pore body size distribution. The approach requires a small micro-CT image volume (7–19 mm3) to reveal key pore microstructural features that control flow and transport properties of highly heterogeneous rocks at the core-scale. Four carbonate rock samples were used to test the proposed approach. Permeability calculations from the introduced approach were validated by comparing laboratory measured permeability of rock cores and permeability estimated using five well-known core-scale empirical model equations. The results show that accounting for the stochastic connectivity of pores results in a probabilistic distribution of flow properties which can be used to upscale pore-scale simulated flow properties to the core-scale. The use of the introduced stochastic pore-scale simulation approach is more beneficial when there is a higher degree of heterogeneity in pore size distribution. This is shown to be the case with permeability and hydraulic tortuosity which are key controls of flow and transport processes in rocks.

Oxidative Hydraulic Fracturing Fluid to Enhance Production from Source Rock Reservoirs

Summary The steep production declines generally observed after hydraulic fracturing in unconventional source rock reservoirs has been attributed to several potential causes. Recently, a new additive to the stimulation fluid system was proposed to extend economical longer-term production from these formations. Oxidizer-laden fracturing fluid systems are shown to create cracks and deep channels within the organic matter present in the source rock, such as kerogen, thereby increasing the source rock permeability and enhancing the hydraulic conductivity of the exposed fracture faces. To this end, the fluid design and recommendations for its application are illustrated herein. Oxidants composed of oxychlorine (ClOn−) and oxybromine (BrOn–) (where n = 0 to 4) are effective for kerogen depolymerization or degradation at depth. This study illustrates the beneficial effects of two specific oxidizers—sodium chlorite (NaClO2) and sodium bromate (NaBrO3)—on kerogen-rich source rock subjected to in-situ reservoir conditions. Source rock samples were cut and polished to test the oxidizer’s impact on the organic and inorganic regions. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were performed on the rock surface to identify specific organic matter features. The samples were then chemically treated with varying conditions of NaClO2 or NaBrO3 (concentration range: 0.013–0.054 M; temperature: 150°C; and time: 3–24 hours). Samples were returned to the scanning electron microscope for post-treatment analysis. Furthermore, the oxidants were packaged within a slickwater hydraulic fracturing fluid system for field application, and their effects on viscosity and friction reduction were also studied. SEM images and EDS maps of kerogen-rich rock samples observed before and after treatment with oxidizing fluid showed a series of cracks formed throughout the organic matter domains, where increasing the concentration of oxidizer in the treatment fluid showed a clear increase in the prevalence of cracks throughout the surface. The effect of time was also observed, as short treatment times resulted in porosity/permeability creation in the kerogen, though longer treatment times were associated with more severe degradation. Optimal conditions for NaClO2 and NaBrO3 concentrations in the additive fluid systems were different and will be herein highlighted. Each oxidizer (10–20 pptg concentration) was added to slickwater with variable friction reducer concentration (1 gpt, 2 gpt, and 4 gpt), and shear sweeps performed at both 70°F and 180°F. A negligible difference is observed between the viscosities of the base fluid and the fluid with either oxidant at low friction reducer concentration. Meanwhile, flow loop tests demonstrated that the oxidizer did not affect the friction reducer except to slightly boost the performance due to the salt effect on the polymer. Two strong oxidants, available as commodity chemicals, are shown to be effective in cracking kerogen and any present organic matter, thus creating permeable channels and enhancing the overall permeability of the exposed source rock fracture faces. Meanwhile, the proposed fracturing fluid additives display good compatibility with other slickwater fluid components, demonstrating the potential for universal usage in unconventional stimulations. The recommendations for its application as a fluid additive in slickwater are herein illustrated.

Influence of boundary conditions on initiation of gas blowout in permeable rock

Free gas in permafrost may originate from dissociating methane hydrates that are widespread in the Arctic region. Methane can migrate through sand–clay permafrost and accumulate there, particularly in sand beds. Gas migration is often accompanied by the formation of pressurised zones. As the pressure reaches some critical value, the overburden breaks down, and methane is released explosively with formation of craters on the seabed. In this paper, gas migration is simulated in two dimensions, with implications for the conditions under which an increased gas flow rate can lead to failure of granular rocks, as well as for the place of blowout initiation depending on boundary conditions. The paper shows that the location of sediment blowouts in the presence of an impermeable lid or obstacle differs from the location of blowouts without them. The paper also shows that the type of pressure source (homogeneous or heterogeneous) also affects the location of the blowout initiation. The numerical results are in good agreement with laboratory experiments carried out in a sandy medium at a Hele-Shaw cell and with field data. The presented results should be taken into account when estimating the after-effects of methane hydrate dissociation due to global warming or due to surface condition changes.

Evaluation of Slow-Releasing Energy Material (SREMA) Injection for In-Situ Rock Breaking Under Uniaxial and Triaxial Loading: An Experimental Study

Permeability enhancement of impervious rock formations is crucial for the exploitation of ore deposits, which are uneconomic using conventional mining methods. These deposits have the potential to be mined with in-situ recovery (ISR) mining methods, provided the deposit’s permeability is enhanced artificially. Slow-releasing energy material (SREMA) has been identified as a promising preconditioning technique to enhance rock permeability for ISR. However, the fracturing potential of SREMA in the presence of in-situ stresses remains under-explored in laboratory experimental research studies and needs to be assessed in detail prior to field trials. A unique confining cell was developed in this study to represent realistic confining stresses underground, and the impacts of different stress conditions on the fracturing potential of SREMA were investigated. In addition, the effects of SREMA expansion in pre-existing joints were also assessed using laboratory fracturing experiments conducted by injecting SREMA into sandstone specimens with artificially created horizontal persistent joints, which is the first attempt to the best of the author’s knowledge. Under uniaxial stress conditions (10 MPa), multiple radial cracks emerged from the borehole at the centre of the specimen, while vertical splitting of the specimen was observed due to the outward expansion of SREMA inside the joint. In comparison, under triaxial confinement (5 MPa and 10 MPa), a decrease in the damage caused to the rock mass due to the expansive pressure generated by SREMA was observed, and this was overcome by introducing multiple injection holes and stress relief holes into the rock mass.

DC electric field assisted heat extraction evaluation via water circulation in abandoned production well patterns: Semi-analytical and numerical models

Geothermal energy, recognized for its clean and vast developmental potential, finds untapped promise in many oil fields developed through water injection. However, challenges such as the high costs associated with drilling and development, the expansion of water-clay expansion, and low rock permeability have constrained the broader exploitation of geothermal resources. Here, to address these challenges and harness low-permeability geothermal energy from abandoned wells, this work introduces a novel approach: DC-assisted circulation water injection technology. This study employs the Green function, Newman product, and boundary element methods to develop semi-analytical and numerical models, incorporating a DC electric field to simulate the optimization effect of this field on heat extraction. This work evaluates and optimize the lifetime and economic effects of abandoned wells using the Non Sorting Genetic Algorithm II. Results show that the semi-analytical model monitors the reservoir temperature parameter to optimize the timing for circulation water injection. Additionally, our numerical model demonstrates that, over a span of 5000 days, a network of wells could generate a revenue of $9.158 million. In summary, DC-assisted abandoned wells to develop geothermal reservoirs is not only feasible but also enhances reservoir permeability and porosity through an electrical conductivity effect, significantly improving heat energy recovery.

Interpretasi Rekahan Hydraulic Fracturing dengan Menggunakan Permodelan Simulator Fraccade Berdasarkan hasil Rock Properties Pada Sumur X Lapangan Y

Interpretation Fractures of Hydraulic fracturing with Fraccade Model Based on Rock Properties Results at Well X Field Y.Identifying fractures based on the results of Rock Properties purpose is to find out and get results during the identification process from the results of Hydraulic fracturing stimulation with the purpose of getting a conclusionwhether or not the operation is successful. Well X has several problems such as high skin and low permeability, because of that Hydraulic fracturing stimulation is the most effective action for this well.The method used is to select data data and the condition of well X to visualize the data results from Fraccade software V 5.4.1. And do calculations using Ms. Excel. The parameters that calculated in this Final Project include rock geometry, rock permeability, and wellbore damage. After identifying and interpreting the data using Fraccade V 5.4.1 software. The results show that not much different between manual calculation and Fraccade software.

The spatio-temporal variation of exhumation and its impacts on the resource distribution in the Northern Carnarvon Basin, Australia

Deformation and rock fracture during exhumation can enhance rock porosity and permeability, thereby improving fluid migration through reservoirs and destroying seal integrity in caprocks. Therefore, analysing the spatio-temporal distribution of exhumation in connection to fluid migration models can be crucial for energy resource exploration and storage. Geological and geophysical evidence suggests that parts of the Northern Carnarvon Basin (NCB) were exhumed. However, the spatio-temporal distribution of this exhumation and its impacts on the region's resource distribution is yet to be established. We analysed porosity, sonic logs and paleotemperature data from 210 boreholes using compaction and vitrinite reflectance analysis techniques to constrain the spatio-temporal distribution of exhumation and its correlation to the region's resource distribution. We discovered that multiple exhumation phases occurred since the Late Triassic. The highest exhumation occurred in the Mid Jurassic, where approximately 1000 m of sediment thickness was eroded from the western and southwestern parts of the Exmouth Plateau. Exhumation at this time spatially correlates with magmatic intrusions in the NCB, and paleotemperature profiles indicate that sediments in the exhumed regions were partly heated by increased paleo-basal heat flow, suggesting that magmatic bodies through underplating and crustal intrusions were the primary causes of this exhumation. Another significant exhumation phase occurred in the Early Cretaceous, removing ∼800 m of sediments from the Exmouth, Barrow and Dampier Sub-basins. Depth-dependent extension events and magmatic intrusions possibly caused exhumation at this time. Significant exhumation ceased in the Early Cretaceous, and our study has established that the exhumation episodes in the NCB were part of large-scale regional events that affected the Australian Northwest Shelf. Combining results from different estimation techniques increased the spatio-temporal coverage of the analysis and improved the precision and accuracy of exhumation results.

Advances in enhanced geothermal systems: Integrating laboratory, numerical and field insights

An enhanced geothermal system is a designed and engineered thermal reservoir that has been deliberately stimulated to extract economically viable amounts of heat from geothermal resources having no natural permeability. Enhanced geothermal system projects are typically initiated to meet the industrial production standards, usually via techniques such as chemical stimulation, hydraulic fracturing, or thermal processes to enhance the permeability of the reservoir. The main aim of this study is to evaluate the current advancements in enhanced geothermal system through a comprehensive examination of laboratory experiments, numerical simulation, and fieldwork investigations from numerous studies that are insufficient captures and combined by current open literature. This study highlighted the critical importance of precisely developing fracture systems, whether natural or artificially induced, in ensuring the effectiveness of such projects. Notably, hydraulic fracturing techniques have been proven instrumental in enhancing the performance of enhanced geothermal systems. On the contrary, research conducted through numerical simulations has demonstrated consistent findings that it is beneficial to enhance the permeability of low-permeability rock for the efficient use of enhanced geothermal systems. Additionally, this study has highlighted the intricate and expensive nature of designing enhanced geothermal systems due to uncertainties in subsurface conditions especially from projects that are in initial stages of development. This study enables researchers and operators to improve the efficiency and safety of geothermal energy extraction, paving the way for more sustainable enhanced geothermal system projects in the future.

Precipitants transport during post-flush and its impacts

Wellbore stimulation is often needed for different situations in the field ranging from deepwater frac-packs to enhanced geothermal systems. Acidizing is commonly designed for cleaning perforation, recovering perforation functions, and improving injectivity during completion operations such as frac-pack, aiming to reduce the fracturing pressure and enhance productivity. However, some field observations have shown unexpected breakdown pressure increases after the post-flush period of acid treatment in sandstone reservoirs. To understand this problem, a 3D model has been established in this paper to simulate the acidizing process through a perforation hole, and then the subsequent post-flush resulting in precipitant transport. Finally, the breakdown process where fluid is injected into the rock is modeled to compare breakdown pressures in different cases. Our numerical results reveal that although minerals can be effectively dissolved by chemical reactions during the main flush period, the generated precipitants transported during the post-flush period may affect the rock breakdown process. The precipitant transport might develop high-porosity channels, potentially leading to the breakthrough along the precipitant deposits and establishing a string hydraulic communication between the perforation hole and the surrounding rock. The existence of these high-porosity channels enables fluids to flow swiftly into the surroundings, impeding enough pressure accumulation to crack the rock. The formation of high-porosity channels in the post-flush period and its potential impact on the breakdown pressure is influenced by several factors such as post-flush fluid injection rate, acid concentration and viscosity, and the initial rock permeability.

The influence of mining stress paths on rock damage and permeability

The influence of mining stress paths on rock damage and permeability

Microbial Mineralization-Based Rapid and High-Strength Simultaneous Repair of Surrounding Rock Fracture Zones and Lining Cracks

Grouting technology based on microbial mineralization represents a novel approach to enhancing the properties of rock and soil. Widely studied for its combination of high efficiency and environmental friendliness, this method improves the strength and permeability of rock and soil. In this study, a novel approach involving bioslurry + filling particles was proposed to reinforce sand columns. It was observed that the addition of filling particles provided new nucleation sites for crystallization, significantly enhancing the cementation effect of sand particles. After 3 days of grouting treatment, sand columns containing 10% filling particles exhibited an order of magnitude reduction in permeability with the unconfined compressive strength (UCS) reaching 2.5 MPa, more than twice that of sand columns reinforced with bioslurry alone. Additionally, this study presented a method for the simultaneous repair of sand particles and concrete cracks. Results indicated that after 3 days of the grouting treatment, the interfacial shear strength between sand columns and concrete reached 100 kPa. Moreover, for concrete with crack apertures less than 1 mm, the permeability coefficient was reduced by over 80%, while the recovery ratio of the splitting tensile strength reached 64.2%. These findings highlight the potential of microbial mineralized grouting technology in addressing practical challenges, providing a foundation for the rapid and high-strength simultaneous repair of tunnel-surrounding rock fracture zones and lining cracks.

Investigation of pore structure evolution and damage characteristics of high temperature rocks subjected to liquid nitrogen cooling shock

Liquid nitrogen (LN2) can be utilized in the development of enhanced geothermal systems, as well as for deep/ultra-deep hydrocarbon reservoir stimulation, fire suppression, and other high-temperature geological projects. It is a crucial issue in the utilization of LN2 to investigate the pore structure evolution, permeability, and damage characteristics of high-temperature rocks under the influence of LN2 cooling shock. These rocks were first slowly heated to 150∼600°C and held for 2 h, followed by LN2 or natural cooling. The evolution of pore volume in high-temperature rocks affected by liquid nitrogen cooling was quantified. T2 cutoff values were determined through centrifugal tests, while the contents of irreducible and mobile fluids were estimated. Based on the aforementioned analysis as well as changes in irreducible fluid saturation, pore throat, tortuosity, and permeability, this study examines the closure and development of pores along with permeability behavior. The findings suggest that, despite a more pronounced decrease in porosity at lower heating temperatures, LN2 cooling specimens exhibit superior pore connectivity and permeability compared to those cooled naturally. LN2 stimulation not only induces crack initiation and propagation but also results in further cooling induced densification based on heating densification. 225°C is considered to be the optimal temperature for cooling contraction induced densification in this study. At higher heating temperatures, the damage to rock cooled with LN2 is more severe than that of naturally cooled. This results in a greater increase in porosity, movable fluid content and proportion, and permeability of LN2 cooled specimens compared to naturally cooled specimens. The damage mechanism can be better understood by the constructed damage model that coordinates the pore increase/decrease and mutual pore transformation from the perspective of pore evolution.

Acoustic vibration restoration of rock permeability while crude oil filtration containing paraffins

The paper presents the results of experimental studies on the filtration of a reservoir fluid (crude oil containing paraffins) through sedimentary rocks under the influence of acoustic vibrations in an ultrasound band. A laboratory rig is assembled that allows for modeling the filtration of a fluid from a reservoir into a well during the propagation of elastic waves from a well. Medium permeability sandstones are the focus of the study. The effect of acoustic vibrations manifests itself in unblocking the pore space and leads to restoration of rock permeability to different extents. Dependences of rock permeability on the frequency of acoustic vibrations are obtained. A model of the influence of acoustic vibrations on paraffin particles is developed.

Gas Fracturing Simulation of Shale-Gas Reservoirs Considering Damage Effects and Fluid–Solid Coupling

With the increasing demand for energy and the depletion of traditional resources, the development of alternative energy sources has become a critical issue. Shale gas, as an abundant and widely distributed resource, has great potential as a substitute for conventional natural gas. However, due to the low permeability of shale-gas reservoirs, efficient extraction poses significant challenges. The application of hydraulic fracturing technology has been proven to effectively enhance rock permeability, but the influence of environmental factors on its efficiency remains unclear. In this study, we investigate the impact of gas fracturing on shale-gas extraction efficiency under varying environmental conditions using numerical simulations. Our simulations provide a comprehensive analysis of the physical changes that occur during the fracturing process, allowing us to evaluate the effects of gas fracturing on rock mechanics and permeability. We find that gas fracturing can effectively induce internal fractures within the rock, and the magnitude of tensile stress decreases gradually during the process. The boundary pressure of the rock mass is an important factor affecting the effectiveness of gas fracturing, as it exhibits an inverse relationship with the gas content present within the rock specimen. Furthermore, the VL constant demonstrates a direct correlation with gas content, while the permeability and PL constant exhibit an inverse relationship with it. Our simulation results provide insights into the optimization of gas fracturing technology under different geological parameter conditions, offering significant guidance for its practical applications.

Integrated assessment of deep geothermal heating investments in Northern Belgium through techno-economic, life cycle, global sensitivity and real options analysis

The decarbonization of the heating sector is crucial for the green transition of the energy mix. This study investigates threefold the economic and environmental performance of deep geothermal heating investments in Northern Belgium First, techno-economic and life cycle assessment (LCA) are performed, followed by a global sensitivity analysis focusing on the geological uncertainty. Lastly, real options analysis (ROA) is employed to investigate the economic and environmental value of the investors’ flexibility. A novel ROA method is proposed that considers the LCA results to calculate development decisions that minimize the expected environmental impact of the investment. The results show that the economic and environmental performance of the investment vary with the energy prices and the electricity mix. The performance of the investment is driven by the plant’s pumping requirements, which are induced by the relatively low rock permeability at the targeted location. Also, the results’ variability mainly originates by uncertainty regarding the permeability value. Nevertheless, the investors’ flexibility adds large economic and environmental value to the investment. However, the development strategies that optimize the economic or the environmental performance of the plant present some trade-offs. This study demonstrates that the economic and environmental performance of deep geothermal heating investments in Northern Belgium can be improved by focusing on the factors that simultaneously drive the costs, environmental impacts, and their variability. It also shows that utilizing the investors’ flexibility to optimize the investment’s economic and environmental performance can add significant value to the investment.

Permeability Effect and Nonlinear Coupling Characteristics of Rock–Soil Interaction with Water

The seepage effect of rock and soil in the process of encountering water follows a nonlinear coupling law between water and rock. According to the permeability of rock and soil during softening with water, changes in particles in rock and soil are related to permeability mechanisms. Based on the assumption of connection between particles in rock and soil, changes in particles before and after water infiltration, the mechanism of water–rock interaction, and the damage to rock and soil are analyzed herein. Combined with fractal theory and percolation theory, the random failure characteristics and nonlinear behavior of water in rock and soil are studied. At the same time, with the help of Fluent 17.0 software, the seepage process of rock samples in water is numerically simulated and analyzed. Taking the permeability coefficient of rock samples, the mass flow rate of water, and the internal pore water pressure of rock samples as tracking objects, it is found that there are obvious nonlinear characteristics in the process of water–rock interaction. The seepage–stress coupling between water and rock forms negative resistance to water seepage. The water infiltration is a slow and then accelerated process and tends to be stable. Research has shown that the coupling effect of seepage between water and rock increases the damage inside the rock and soil, and its permeability fluctuates randomly at different time steps. This feature is a common manifestation of fractal properties and percolation within rock and soil particles. At the same time, there is a non-equilibrium variation law of pore water pressure inside the rock and soil. This leads to a continuous strengthening of the seepage effect, reaching a stable state. The results of this study are crucial. It not only reveals the mechanism of interaction between water and rock but also correlates the degree of internal damage in rock and soil based on the seepage characteristics between water and rock. The conclusions can provide some reference value for relevant construction methods in the analysis of the formation of water flow characteristics, the prevention of rock slope seepage disasters, and the control of water inrush in tunnel excavation.

Numerical modeling of the mineralizing processes within the Shaxi porphyry-type Cu-Au deposit, Eastern China: Influence and restriction from physical and chemical characteristics of host rocks

The Shaxi porphyry-type Cu-Au deposit is located in the northwestern outer margin of the Luzong volcanic basin, which is situated in the Middle-Lower Yangtze River Metallogenic Belt (MLYRMB), Eastern China. It is a large porphyry-type Cu-Au deposit with confirmed copper resources exceeding 1 Mt and gold resources exceeding 40 tons. Previous studies have extensively investigated the genesis, controlling structures, geochemical characteristics, fluid evolution, alteration zone, and ages of mineralization and host rocks in this deposit. However, research on the influence of the physical and chemical properties of the host rocks on the mineralizing processes has not been explored in detail. This study employs the finite element method to apply numerical modeling of multiple physical and chemical fields, interlinking heat transfer, fluid flow, material migration, mineralization reaction, and their coupling with porosity and permeability of rock, to investigation of the influence of different porosities, permeabilities, and chemical properties of the host rocks on the mineralizing processes in the Shaxi deposit. The results show that the porosity and permeability of the host rocks play a significant role in the mineralization of porphyry-type systems. The different porosity and permeability of the intrusions and strata control the depth, the mineralization intensity, the morphology of the ore bodies, and the spatial location of the mineralization center. The chemical properties of the strata significantly restrict the mineralization intensity and horizontal spatial rather than affecting the depth of mineralization. Furthermore, the formation of skarn-type deposits may require a longer period of time than that of porphyry-type deposits under the same mineralization conditions and ore grade. This paper also indicates that the numerical modeling method employed in this study can be used to predict the mineralization depth and spatial location of deep concealed porphyry-type deposits, aiding research in deep-seated mineral exploration.

Investigating the CO2 injection and the performance of nanoparticles in preventing formation damage at different pressures and concentrations

AbstractAsphaltene deposition is one of the main challenges during CO2 injection (miscible or immiscible) into reservoirs. Asphaltene deposition reduces the porosity and permeability of reservoir rock and changes its wettability to strongly oil‐wet. In this article, to control the asphaltene deposition during CO2 injection the use of direct asphaltene inhibitors (Al2O3 and Fe3O4) in reservoir conditions. In this research, nanoparticle screening (to investigate its significance in reducing asphaltene precipitation) has been done and it can be stated that Al2O3 nanoparticle will perform better effectivity than Fe3O4 nanoparticle. After that, by using effective nanoparticles (Al2O3) in different concentrations (1000 and 2000 ppm), the amount of asphaltene deposition during CO2 injection has been investigated. The obtained results show that increasing the injection pressure (from immiscible to miscible) causes an increase in asphaltene deposition and the use of nanoparticles will reduce the amount of asphaltene deposition.

EFFECT OF GRAPHENE OXIDE AQUEOUS DISPERSIONS ON ROCK WETTABILITY

Among the various methods to improve oil recovery from reservoirs (wells stimulation), the use of nanofluids has emerged as a promising alternative for modifying the wettability and permeability of sandstone rocks. For this reason, in this study, graphene oxide (GO) was synthesized from graphite, and a nanofluid was formulated using GO dispersed in water to evaluate its capacity for modifying wettability on sandstone core plugs from Colombian reservoirs. The experimental setup included three preliminary tests: visual wettability, contact angle measurements, and detergency. The results demonstrated an increase in the water wettability of the rocks, leading to a decrease in the contact angle of the water-rock system by up to 42.6%. Additionally, the visual wettability and detergency tests yielded positive results, indicating that graphene oxide is an effective wettability modifier, rendering the rock more water-wet.