Download or read book Modeling The Effects Of Salt Precipitation And Kinetic Mineral Reaction On Well Injectivity Due To Carbon Dioxide Injection In Deep Saline Aquifers written by Kojo Yeboa and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Little is known about the complex processes taking place between CO2, the host formation, and in-situ brine at the conditions found within deep saline aquifers during CO2 injection for the purposes of long term sequestration. Mineral dissolution and precipitation reactions which take place in response to the acidic environment formed once CO2 is injected in addition to the precipitation of mineral halite induced by the vaporization of the brine phase into the flowing dry CO2 phase have the potential to alter formation porosity and permeability, negatively impacting well injectivity. A commercial reservoir simulator was used to develop several studies in order to observe the scale and extent of host mineral dissolution and precipitation as well as halite mineral precipitation following CO2 injection into a siliciclastic deep saline formation. Dissolution was observed to be the predominant mineral reaction however limited scale resulted in minimal impact on well injectivity. Halite precipitation in the near well region was found to provide limited impacts on well injectivity. Following a sensitivity study, the initial formation salinity was found to be a property significant in impacting halite precipitation, however even at high saline concentrations impacts to well injectivity are considered of little note and could be effectively negated with a relatively brief three-month fresh water injection period prior to the onset of CO2 injection.
Download or read book An Experimental and Numerical Investigation Into Permeability and Injectivity Changes During CO2 Storage in Saline Aquifers written by Giacomo Bacci and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thermochemical based Poroelastic Modelling of Salt Crystallization and a New Multiphase Flow Experiment written by Florian Osselin and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In a context of international reduction of greenhouse gases emissions, CCS (ce{CO2} Capture and Storage) appears as a particularly interesting midterm solution. Indeed, geological storage capacities may raise to several millions of tons of ce{CO2} injected per year, allowing to reduce substantially the atmospheric emissions of this gas. One of the most interesting targets for the development of this solution are the deep saline aquifers. These aquifers are geological formations containing brine whose salinity is often higher than sea water's, making it unsuitable for human consumption. However, this solution has to cope with numerous technical issues, and in particular, the precipitation of salt initially dissolved in the aquifer brine. Consequences of this precipitation are multiple, but the most important is the modification of the injectivity i.e. the injection capacity. Knowledge of the influence of the precipitation on the injectivity is particularly important for both the storage efficiency and the storage security and durability. The aim of this PhD work is to compare the relative importance of negative (clogging) and positive (fracturing) phenomena following ce{CO2} injection and salt precipitation. Because of the numerous simulations and modelling results in the literature describing the clogging of the porosity, it has been decided to focus on the mechanical effects of the salt crystallization and the possible deformation of the host rock. A macroscopic and microscopic modelling has then been developed, taking into account two possible modes of evaporation induced by the spatial distribution of residual water, in order to predict the behavior of a porous material subjected to the drying by carbon dioxide injection. Results show that crystallization pressure created by the growth of a crystal in a confined medium can reach values susceptible to locally exceed the mechanic resistance of the host rock, highlighting the importance of these phenomena in the global mechanical behavior of the aquifer. At the experimental level, the study of a rock core submitted to the injection of supercritical carbon dioxide has been proceeded on a new reactive percolation prototype in order to obtain the evolution of permeabilities in conditions similar to these of a deep saline aquifer.
Download or read book Formation Dry out from CO2 Injection Into Saline Aquifers written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Injection of CO2 into saline aquifers may cause formation dry-out and precipitation of salt near the injection well, which may reduce formation porosity, permeability, and injectivity. This paper uses numerical simulation to explore the role of different processes and parameters in the salt precipitation process and to examine injection strategies that could mitigate the effects. The main physical mechanisms affecting the dry-out and salt precipitation process include (1) displacement of brine away from the injection well by injected CO2, (2) dissolution (evaporation) of brine into the flowing CO2 stream, (3) upflow of CO2 due to gravity effects (buoyancy), (4) backflow of brine toward the injection point due to capillary pressure gradients that oppose the pressure gradient in the CO2-rich ('gas') phase, and (5) molecular diffusion of dissolved salt. The different mechanisms operate on a range of spatial scales. CO2 injection at constant rate into a homogeneous reservoir with uniform initial conditions is simulated in 1-D radial geometry, to resolve multiscale processes by taking advantage of the similarity property, i.e., the evolution of system conditions as a function of radial distance R and time t depends only on the similarity variable R2/t. Simulations in 2-D vertical cross sections are used to examine the role of gravity effects. We find that counterflow of CO2 and brine can greatly increase aqueous phase salinity and can promote substantial salt precipitation even in formations with low dissolved solids. Salt precipitation can accentuate effects of gravity override. We find that injecting a slug of fresh water prior to commencement of CO2 injection can reduce salt precipitation and permeability loss near the injection well.
Download or read book Geometric Modelling Numerical Simulation and Optimization written by Geir Hasle and published by Springer Science & Business Media. This book was released on 2007-06-10 with total page 559 pages. Available in PDF, EPUB and Kindle. Book excerpt: This edited volume addresses the importance of mathematics for industry and society by presenting highlights from contract research at the Department of Applied Mathematics at SINTEF, the largest independent research organization in Scandinavia. Examples range from computer-aided geometric design, via general purpose computing on graphics cards, to reservoir simulation for enhanced oil recovery. Contributions are written in a tutorial style.
Download or read book Geological Carbon Storage written by Stéphanie Vialle and published by John Wiley & Sons. This book was released on 2018-11-15 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: Geological Carbon Storage Subsurface Seals and Caprock Integrity Seals and caprocks are an essential component of subsurface hydrogeological systems, guiding the movement and entrapment of hydrocarbon and other fluids. Geological Carbon Storage: Subsurface Seals and Caprock Integrity offers a survey of the wealth of recent scientific work on caprock integrity with a focus on the geological controls of permanent and safe carbon dioxide storage, and the commercial deployment of geological carbon storage. Volume highlights include: Low-permeability rock characterization from the pore scale to the core scale Flow and transport properties of low-permeability rocks Fundamentals of fracture generation, self-healing, and permeability Coupled geochemical, transport and geomechanical processes in caprock Analysis of caprock behavior from natural analogues Geochemical and geophysical monitoring techniques of caprock failure and integrity Potential environmental impacts of carbon dioxide migration on groundwater resources Carbon dioxide leakage mitigation and remediation techniques Geological Carbon Storage: Subsurface Seals and Caprock Integrity is an invaluable resource for geoscientists from academic and research institutions with interests in energy and environment-related problems, as well as professionals in the field.
Download or read book Experimental and Numarical Investigation of Carbon Dioxide Sequestration in Deep Saline Aquifers written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Started as an EOR technique to produce oil, injection of carbon dioxide which is essentially a greenhouse gas is becoming more and more important. Although there are a number of mathematical modeling studies, experimental studies are limited and most studies focus on injection into sandstone reservoirs as opposed to carbonate ones. This study presents the results of computerized tomography (CT) monitored laboratory experiments to characterize relevant chemical reactions associated with injection and storage of CO2 in carbonate formations. Porosity changes along the core plugs and the corresponding permeability changes are reported for varying CO2 injection rates, temperature and salt concentrations. CT monitored experiments are designed to model fast near well bore flow and slow reservoir flows. It was observed that either a permeability improvement or a permeability reduction can be obtained. The trend of change in rock properties is very case dependent because it is related to distribution of pores, brine composition and as well the thermodynamic conditions. As the salt concentration decreased the porosity and thus the permeability decrease was less pronounced. Calcite scaling is mainly influenced by orientation and horizontal flow resulted in larger calcite deposition compared to vertical flow. The duration of CO2 – rock contact and the amount of area contacted by CO2 seems to have a more pronounced effect compared to rate effect. The experiments were modeled using a multi-phase, non-isothermal commercial simulator where solution and deposition of calcite were considered by the means of chemical reactions. The calibrated model was then used to analyze field scale injections and to model the potential CO2 sequestration capacity of a hypothetical carbonate aquifer formation. It was observed that solubility and hydrodynamic storage of CO2 is larger compared to mineral trapping.
Download or read book Formation Damage Due to CO2 Sequestration in Saline Aquifers written by Ibrahim Mohamed Mohamed and published by . This book was released on 2013 with total page 221 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon dioxide (CO2) sequestration is defined as the removal of gas that would be emitted into the atmosphere and its subsequent storage in a safe, sound place. CO2 sequestration in underground formations is currently being considered to reduce the amount of CO2 emitted into the atmosphere. However, a better understanding of the chemical and physical interactions between CO2, water, and formation rock is necessary before sequestration. These interactions can be evaluated by the change in mineral content in the water before and after injection, or from the change in well injectivity during CO2 injection. It may affect the permeability positively due to rock dissolution, or negatively due to precipitation. Several physical and chemical processes cover the CO2 injection operations; multiphase flow in porous media is represented by the flow of the brine and CO2, solute transportation is represented by CO2 dissolution in the brine forming weak carbonic acid, dissolution-deposition kinetics can be seen in the rock dissolution by the carbonic acid and the deposition of the reaction products, hydrodynamic instabilities due to displacement of less viscous brine with more viscous CO2 (viscous fingering), capillary effects and upward movement of CO2 due to gravity effect. The objective of the proposed work is to correlate the formation damage to the other variables, i.e. pressure, temperature, formation rock type, rock porosity, water composition, sulfates concentration in the water, CO2 volume injected, water volume injected, CO2 to water volumetric ratio, CO2 injection rate, and water injection rate. In order to achieve the proposed objective, lab experiments will be conducted on different rock types (carbonates, limestone and dolomite, and sandstone) under pressure and temperature that simulate the field conditions. CO2 will be used at the supercritical phase and different CO2-water-rock chemical interactions will be addressed. Quantitative analysis of the experimental results using a geochemical simulator (CMG-GEM) will also be performed. The results showed that for carbonate cores, maintaining the CO2/brine volumetric ratio above 1.0 reduced bicarbonate formation in the formation brine and helped in minimizing precipitation of calcium carbonate. Additionally, increasing cycle volume in WAG injection reduced the damage introduced to the core. Sulfate precipitation during CO2 sequestration was primarily controlled by temperature. For formation brine with high total dissolved solids (TDS), calcium sulfate precipitation occurs, even at a low sulfate concentration. For dolomite rock, temperature, injection flow rate, and injection scheme don't have a clear impact on the core permeability, the main factor that affects the change in core permeability is the initial core permeability. Sandstone cores showed significant damage; between 35% and 55% loss in core permeability was observed after CO2 injection. For shorter WAG injection the damage was higher; decreasing the brine volume injected per cycle, decreased the damage. At higher temperatures, 200 and 250°F, more damage was noted than at 70°F. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/148153
Download or read book Geologic Carbon Sequestration written by V. Vishal and published by Springer. This book was released on 2016-05-11 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: This exclusive compilation written by eminent experts from more than ten countries, outlines the processes and methods for geologic sequestration in different sinks. It discusses and highlights the details of individual storage types, including recent advances in the science and technology of carbon storage. The topic is of immense interest to geoscientists, reservoir engineers, environmentalists and researchers from the scientific and industrial communities working on the methodologies for carbon dioxide storage. Increasing concentrations of anthropogenic carbon dioxide in the atmosphere are often held responsible for the rising temperature of the globe. Geologic sequestration prevents atmospheric release of the waste greenhouse gases by storing them underground for geologically significant periods of time. The book addresses the need for an understanding of carbon reservoir characteristics and behavior. Other book volumes on carbon capture, utilization and storage (CCUS) attempt to cover the entire process of CCUS, but the topic of geologic sequestration is not discussed in detail. This book focuses on the recent trends and up-to-date information on different storage rock types, ranging from deep saline aquifers to coal to basaltic formations.
Download or read book Geochemical and Biogeochemical Reaction Modeling written by Craig M. Bethke and published by Cambridge University Press. This book was released on 2010-12-09 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive overview of reaction processes in the Earth's crust and on its surface, both in the laboratory and in the field. A clear exposition of the underlying equations and calculation techniques is balanced by a large number of fully worked examples. The book uses The Geochemist's Workbench® modeling software, developed by the author and already installed at over 1000 universities and research facilities worldwide. Since publication of the first edition, the field of reaction modeling has continued to grow and find increasingly broad application. In particular, the description of microbial activity, surface chemistry, and redox chemistry within reaction models has become broader and more rigorous. These areas are covered in detail in this new edition, which was originally published in 2007. This text is written for graduate students and academic researchers in the fields of geochemistry, environmental engineering, contaminant hydrology, geomicrobiology, and numerical modeling.
Download or read book Science of Carbon Storage in Deep Saline Formations written by Pania Newell and published by Elsevier. This book was released on 2018-09-10 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Science of Carbon Storage in Deep Saline Formations: Process Coupling across Time and Spatial Scales summarizes state-of-the-art research, emphasizing how the coupling of physical and chemical processes as subsurface systems re-equilibrate during and after the injection of CO2. In addition, it addresses, in an easy-to-follow way, the lack of knowledge in understanding the coupled processes related to fluid flow, geomechanics and geochemistry over time and spatial scales. The book uniquely highlights process coupling and process interplay across time and spatial scales that are relevant to geological carbon storage.
Download or read book Reactive Transport Modelling of CO2 Storage in Saline Aquifers to Elucidate Fundamental Processes Trapping Mechanisms and Sequestration Partitioning written by and published by . This book was released on 2004 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ultimate fate of CO2 injected into saline aquifers for environmental isolation is governed by three interdependent yet conceptually distinct processes: CO2 migration as a buoyant immiscible fluid phase, direct chemical interaction of this rising plume with ambient saline waters, and its indirect chemical interaction with aquifer and cap-rock minerals through the aqueous wetting phase. Each process is directly linked to a corresponding trapping mechanism: immiscible plume migration to hydrodynamic trapping, plume-water interaction to solubility trapping, and plume-mineral interaction to mineral trapping. In this study, reactive transport modeling of CO2 storage in a shale-capped sandstone aquifer at Sleipner has elucidated and established key parametric dependencies of these fundamental processes, the associated trapping mechanisms, and sequestration partitioning among them during consecutive 10-year prograde (active-injection) and retrograde (post-injection) regimes. Intra-aquifer permeability structure controls the path of immiscible CO2 migration, thereby establishing the spatial framework of plume-aquifer interaction and the potential effectiveness of solubility and mineral trapping. Inter-bedded thin shales--which occur at Sleipner--retard vertical and promote lateral plume migration, thereby significantly expanding this framework and enhancing this potential. Actual efficacy of these trapping mechanisms is determined by compositional characteristics of the aquifer and cap rock: the degree of solubility trapping decreases with increasing formation-water salinity, while that of mineral trapping is proportional to the bulk concentration of carbonate-forming elements--principally Fe, Mg, Ca, Na, and Al. In the near-field environment of Sleipner-like settings, 80-85% by mass of injected CO2 remains and migrates as an immiscible fluid phase, 15-20% dissolves into formation waters, and less than 1% precipitates as carbonate minerals. This partitioning defines the relative effectiveness of hydrodynamic, solubility, and mineral trapping on a mass basis. Seemingly inconsequential, mineral trapping has enormous strategic significance: it maintains injectivity, delineates the storage volume, and improves cap-rock integrity. We have identified four distinct mechanisms: dawsonite [NaAlCO3(OH)2] cementation occurs throughout the intra-aquifer plume, while calcite-group carbonates [principally, (Fe, Mg, Ca)CO3] precipitate via disparate processes along lateral and upper plume margins, and by yet another process within inter-bedded and cap-rock shales. The coupled mineral dissolution/precipitation reaction associated with each mechanism reduces local porosity and permeability. For Sleipner-like settings, the magnitude of such reduction for dawsonite cementation is near negligible; hence, this process effectively maintains initial CO2 injectivity. Of similarly small magnitude is the reduction associated with formation of carbonate rind along upper and lateral plume boundaries; these processes effectively delineate the CO2 storage volume, and for saline aquifers anomalously rich in Fe-Mg-Ca may partially self-seal the plume. Porosity and permeability reduction is most extreme within shales, because their clay-rich mineralogy defines bulk Fe-Mg concentrations much greater than those of saline aquifers. In the basal cap-rock shale of our models, these reductions amount to 4.5 and 13%, respectively, after the prograde regime. During the retrograde phase, residual saturation of immiscible CO2 maintains the prograde extent of solubility trapping while continuously enhancing that of mineral trapping. At the close of our 20-year simulations, initial porosity and permeability of the basal cap-rock shale have been reduced by 8 and 22%, respectively. Extrapolating to hypothetical complete consumption of Fe-Mg-bearing shale minerals (here, 10 vol.% Mg-chlorite) yields an ultimate reduction of about 52 and 90%, respectively, after 130 years. Hence, the most crucial strategic impact of mineral trapping in Sleipner-like settings: it continuously improves hydrodynamic seal integrity of the cap rock and, therefore, containment of the immiscible plume and solubility trapped CO2.
Download or read book Geomechanical Geochemical and Hydrological Aspects of Co2 Injection Into Saline Reservoirs written by Maziar Foroutan and published by . This book was released on 2021 with total page 686 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon dioxide Capturing, and Sequestration (CCS) is a promising technique that helps mitigate the amount of CO2 emitted into the atmosphere. CCS process mainly involves capturing CO2 at the industrial plant, followed by transportation and injection into a suitable geological storage, under supercritical conditions. Saline aquifers are among the best geological storage candidates due to their availability, high storage capacity and injectivity. Despite the CCUS technology promise, several public safety concerns remain to be address, including but not limited to reservoir/wellbore stability and integrity, CO2 leakage, ground deformation (uplift) and induced seismicity. The injected supercritical CO2 is trapped through different mechanisms in the host reservoir including (i) structural and stratigraphic trapping, (ii) residual trapping, (iii) solubility trapping, and (iv) mineral trapping. Dissolution of CO2 into the formation brine creates an acidic environment, which is highly reactive. The potential mineral dissolution in reservoir rocks can enhance the storage capacity and reservoir injectivity, while the secondary precipitation of minerals can decrease the storage capacity and injectivity. However, the geochemical processes triggered by CO2 injection can potentially degrade the mechanical properties of the reservoir rock, which can consequently disturb the wellbore-stability, reservoir integrity, and lead to significant reservoir compaction. Furthermore, injecting CO2 changes the stress-regime by increasing pore-pressure in the reservoir and its surroundings, which can potentially reactivate the existing faults, leading to induced seismicity. In this research, experiments were performed to evaluate the variation of porosity and pore-connectivity of intact sandstone specimens upon injecting CO2-enriched brine. In addition, the permeability evolution during the CO2-enriched brine injection process was evaluated under different reservoir condition. The mechanical impacts of injecting CO2-enriched brine were evaluated by comparing the mechanical properties (i.e., elastic, strength, seismic and time dependent properties) before and after injecting CO2-enriched brine. In addition, to evaluate the response of fractured reservoirs to CO2 injection, CO2-enriched brine was injected into a limestone and varyingly cemented (i.e., calcite and quartz cemented) sandstone specimens that were artificially fractured. The experimental results were used to numerically simulate CO2 injection into a core-scale porous medium to investigate the changes in CO2 concentration and mass transfer mechanism under different porosity, permeability, and injection pressure values. The experimental results of injecting CO2-enrihed brine to the intact (non-fractured) specimens revealed permeability enhancement and mechanical weakening caused by mineral dissolution. The extent of changes in permeability and mechanical properties of rock specimens varied under different reservoir conditions (i.e., pressure, salinity, and temperature). The mechanical weakening increased the possibility of induced seismicity, which consequently resulted in decreasing the allowable injection pressure of CO2. However, the permeability increase resulted in enhancing CO2 mass transfer and accelerating the solubility trapping in the brine aquifer.
Download or read book The Effects of Salt Precipitation During CO2 Injection Into Deep Saline Aquifer and Remediation Techniques written by Donatus Edem and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This note is part of Quality testing.
Download or read book Processes Related to Hydrodynamic and Mineral Trapping for the Purpose of Carbon Storage in Deep Saline Aquifers written by Ruth E. Jacob and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Anthropogenic sources have caused the rise of CO2 in the atmosphere, necessitating the reduction of the release of this gas from major point sources. An important mitigation technique is the injection of CO2 into deep saline reservoirs as part of CO2 capture and storage (CCS). However, there are gaps in the understanding of the medium- to long-term processes for the safe and efficient storage of CO2. Solubility trapping involves the dissolution of CO2 into brine, causing the formation of carbonic acid, which increases brine density. Additional waste gases from fossil fuel production, such as SO2, can also be injected and increases density further. As CO2 migrates away from the injection site, more CO2 is able to dissolve and interact with the formation. The dissolution of minerals within the formation changes the porosity and permeability of the rock and provides ions to ultimately precipitate CO2 as part of the mineral trapping process. Solubility and mineral trapping are both important processes for retaining CO2 in saline reservoirs. Solubility of CO2 in multi-salt brines is poorly understood, especially at conditions relevant to CCS. In addition, it may be more feasible to inject SO2 with CO2 because of the cost benefit. There is little data on how co-dissolved SO2 will affect CO2 solubility. CO2 solubility was measured in brines containing NaCl, KCl, CaCl2 and MgCl2 as well as co-dissolved with 2% SO2 in DI and 1 mole/kg NaCl at 297 K and pressures up to 14 MPa. CO2 solubility is affected by the concentration and composition of multi-salt brines but not by the presence of the limited amount of SO2. Although potential injection horizons contain mostly the nonreactive mineral quartz, silicates provide ions for the eventual precipitation of new minerals. Experiments were conducted using crushed and sieved albite in a 0.7 mole/kg KCl brine at room temperature, 35ðC, 75ðC and 100ðC at pressures up to 9.3 MPa for up to 546 days. The concentration of Na, Al, Si and Fe were measured. Dissolution rates were calculated based on release of Si and were found to vary depending on temperature and pH of the solution.
Download or read book Climate Change Carbon Capture Storage and CO2 Mineralisation Technologies written by Nikolaos Koukouzas and published by MDPI. This book was released on 2020-12-04 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Special Issue delivered 16 scientific papers, with the aim of exploring the application of carbon capture and storage technologies for mitigating the effects of climate change. Special emphasis has been placed on mineral carbonation techniques that combine innovative applications to emerging problems and needs. The aim of this Special Issue is to contribute to improved knowledge of the ongoing research regarding climate change and CCS technological applications, focusing on carbon capture and storage practices. Climate change is a global issue that is interrelated with the energy and petroleum industry.
Download or read book Up Scaling Geochemical Reaction Rates for Carbon Dioxide CO2 in Deep Saline Aquifers written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Geochemical reactions in deep subsurface environments are complicated by the consolidated nature and mineralogical complexity of sedimentary rocks. Understanding the kinetics of these reactions is critical to our ability to make long-term predictions about subsurface processes such as pH buffering, alteration in rock structure, permeability changes, and formation of secondary precipitates. In this project, we used a combination of experiments and numerical simulation to bridge the gap between our knowledge of these reactions at the lab scale and rates that are meaningful for modeling reactive transport at core scales. The focus is on acid-driven mineral dissolution, which is specifically relevant in the context of CO2-water-rock interactions in geological sequestration of carbon dioxide. The project led to major findings in three areas. First, we modeled reactive transport in pore-network systems to investigate scaling effects in geochemical reaction rates. We found significant scaling effects when CO2 concentrations are high and reaction rates are fast. These findings indicate that the increased acidity associated with geological sequestration can generate conditions for which proper scaling tools are yet to be developed. Second, we used mathematical modeling to investigate the extent to which SO2, if co-injected with CO2, would acidify formation brines. We found that there exist realistic conditions in which the impact on brine acidity will be limited due to diffusion rate-limited SO2 dissolution from the CO2 phase, and the subsequent pH shift may also be limited by the lack of availability of oxidants to produce sulfuric acid. Third, for three Viking sandstones (Alberta sedimentary basin, Canada), we employed backscattered electron microscopy and energy dispersive X-ray spectroscopy to statistically characterize mineral contact with pore space. We determined that for reactive minerals in sedimentary consolidated rocks, abundance alone is not a good predictor of mineral accessible surface area, and should not be used in reactive transport modeling. Our work showed that reaction rates would be overestimated by three to five times.
