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1
Dalkhaa, Chantsalmaa. "Cap Rock Integrity In Co2 Storage." Phd thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612263/index.pdf.
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One way to reduce the amount of CO2 in the atmosphere for the mitigation of climate change is to capture the CO2 and inject it into geological formations. The most important public concern about carbon capture and storage (CCS) is whether stored CO2 will leak into groundwater sources and finally into the atmosphere.
To prevent the leakage, the possible leakage paths and the mechanisms triggering the paths must be examined and identified. It is known that the leakage paths can be due to CO2 - rock interaction and CO2 &ndash<br>well interaction.
The objective of this research is to identify the geochemical reactions of the dissolved CO2 in the synthetic formation water with the rock minerals of the Sayindere cap rock by laboratory experiments. It is also aimed to model and simulate the experiments using ToughReact software. Sayindere formation is the cap rock of the Caylarbasi, a southeastern petroleum field in Turkey.
The mineralogical investigation and fluid chemistry analysis of the experiments show that calcite was dissolved from the cap rock core as a result of CO2- water- rock interaction.
Using the reactive transport code TOUGHREACT, the modeling of the dynamic experiment is performed. Calcite, the main primary mineral in the Sayindere is dissolved first and then re-precipitated during the simulation process. The decreases of 0.01 % in the porosity and 0.03% in permeability of the packed core of the Sayindere cap rock are observed in the simulation.
The simulation was continued for 25 years without CO2 injection. However, the results of this simulation show that the porosity and permeability are increased by 0.001 % and 0.004 %, respectively due to the CO2-water-rock mineral interaction. This shows that the Sayindere cap rock integrity must be monitored in the field if application is planned.
2
Okwen, Roland Tenjoh. "Enhanced CO2 Storage in Confined Geologic Formations." Scholar Commons, 2009. http://scholarcommons.usf.edu/etd/3683.
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Many geoscientists endorse Carbon Capture and Storage (CCS) as a potential strategy
for mitigating emissions of greenhouse gases. Deep saline aquifers have been reported to
have larger CO
2 storage capacity than other formation types because of their availability
worldwide and less competitive usage. This work proposes an analytical model for screening
potential CO
2 storage sites and investigates injection strategies that can be employed to
enhance CO
2 storage.
The analytical model provides of estimates CO 2
storage efficiency, formation pressure
profiles, and CO 2
–brine interface location. The results from the analytical model were
compared to those from a sophisticated and reliable numerical model (TOUGH 2
). The
models showed excellent agreement when input conditions applied in both were similar.
Results from sensitivity studies indicate that the agreement between the analytical model
and TOUGH2 strongly depends on irreducible brine saturation, gravity and on the relationship
between relative permeability and brine saturation.
A series of numerical experiments have been conducted to study the pros and cons of
different injection strategies for CO 2 storage in confined saline aquifers. Vertical, horizontal,
and joint vertical and horizontal injection wells were considered. Simulations results
show that horizontal wells could be utilized to improve CO 2 storage capacity and efficiency
in confined aquifers under pressure-limited conditions with relative permeability
ratios greater than or equal to 0:01. In addition, joint wells are more efficient than single
vertical wells and less efficient than single horizontal wells for CO 2 storage in anisotropic
aquifers.
3
Prestegård, Elisabeth K. "A GPU Accelerated Simulator for CO2 Storage." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for fysikk, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-24542.
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The goal of this thesis has been to develop a fast simulator for large-scale migration of CO2 in saline aquifers. We have also focused on being able to let the CO2 storage atlas from the Norwegian Petroleum Directorate specify the reservoir properties. In order to meet the demands of simulating on large data sets combined with high performance, we have investigated the possibilities of using graphic processing units (GPUs) to accelerate the computations.The Intergovernmental Panel on Climate Change, IPCC, has considered CO2 to be one of the main factors influencing the climate changes of today. Capture and storage of CO2 is one of the strategies which could reduce the amount of CO2 released into the atmosphere. However, there are still uncertainties related to flow of CO2 in saline aquifers. It is therefore necessary with fast simulators which can predict this behavior to minimize the risks involved in a storage project.GPUs are initially designed to accelerate graphic operations. As opposed to standard CPUs, where most of the transistor capacity is used on advanced logic, the GPU uses most of its transistors on floating point operations in parallel. This results in that the theoretical upper bound for floating point operations are 7-10 times higher on the GPU than the CPU. Thus, GPUs have shown to be a strong tool when solving hyperbolic conservation laws using stencil based schemes, as a large amount of the computations can be parallelized.In compliance with the storage atlases we have based our simulator on structured grids. Our numerical scheme consists of a finite volume method combined with an explicit Euler method.
4
Wang, Zhiyu. "Effects of Impurities on CO2 Geological Storage." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32061.
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This project studied the physical and chemical effects of typical impurities on CO2 storage using both experimental approaches and theoretical simulation. Results show that the presence of typical non-condensable impurities from oxyfuel combustion such as N2, O2, and Ar resulted in lower density than pure CO2, leading to decreased CO2 storage capacity and increased buoyancy in saline aquifers. In contrast, inclusion of condensable SO2 in CO2 resulted in higher density than pure CO2 and therefore increased storage capacity. These impurities also had a significant impact on the phase behaviours of CO2, which is important to CO2 transportation. Different effects on rock chemistry were detected with experimental systems containing pure CO2, CO2 with SO2, or CO2 with SO2 and O2 under conditions simulating that in a potential storage site. An equation was proposed to predict the effects of the rock chemistry on the porosity of rocks.
5
Shen, Jiyun. "Reactive transport modeling of CO2 through cementitious materials under CO2 geological storage conditions." Phd thesis, Université Paris-Est, 2013. http://tel.archives-ouvertes.fr/tel-00861130.
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A reactive transport model is proposed to simulate the reactivity of cement based material in contact with CO2-saturated brine and supercritical CO2 (scCO2) under CO2 geological storage conditions. This code is developed to solve simultaneously transport and chemistry by a global coupled approach, considering the effect of temperature and pressure. The variability of scCO2 properties with pressure and temperature, such as solubility in water, density and viscosity are taken into account. It is assumed that all chemical processes are in thermodynamical equilibrium. Dissolution and precipitation reactions for portlandite (CH) and calcite (CC) are described by mass action laws and threshold of ion activity products in order to account for complete dissolved minerals. A chemical kinetics for the dissolution and precipitation of CH and CC is introduced to facilitate numerical convergence. One properly chosen variable is able to capture the precipitation and dissolution of the relevant phase. A generalization of the mass action law is developed and applied to calcium silicate hydrates (C-S-H) to take into account the continuous variation (decrease) of the Ca/Si ratio during the dissolution reaction of C-S-H. The changes in porosity and microstructure induced by the precipitation and dissolution reactions are also taken into account. Couplings between transport equations and chemical reactions are treated thanks to five mass balance equations written for each atom (Ca, Si, C, K, Cl) as well as one equation for charge balance and one for the total mass. Ion transport is described by using the Nernst-Plank equation as well as advection, while gas and liquid mass flows are governed by advection. Effect of the microstructure and saturation change during carbonation to transport properties is also considered. The model is implemented within a finite-volume code, Bil. Principles of this method and modeling approach are discussed and illustrated with the help of a simple example. This model, with all the efforts above, is able to simulate the carbonation processes for cement based materials, at both saturated and unsaturated conditions, in a wide CO2 concentration, temperature and pressure range. Several sets of experiments, including sandstone-like conditions, limestone-like conditions, supercritical CO2 boundary and unsaturated conditions reported in the literature are simulated. Good predictions are provided by the code when compared with experimental observations. Some experimental observed phenomena are also explained by the model in terms of calcite precipitation front, CH dissolution front, porosity profile, etc
6
Stausland, Jørgen. "Generating a Regression Model Proxy for CO2 storage." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for petroleumsteknologi og anvendt geofysikk, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-26102.
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CO2 storage is regarded an important asset in reducing total CO<sub>2</sub> emissions to the atmosphere. Several methods for storing CO2 have been proposed, but underground storage in saline aquifers are among the most promising. Storing CO2 underground is a comprehensive process that requires thorough understanding of aquifer behavior which is acquired through reservoir simulations, which are time consuming and data demanding. Injection is an expensive process and to save cost it is desirable to optimize the injection process. Optimization of injection scenarios require many reservoir simulations. It is desirable to save time on simulating different injection scenarios, and proxy can be created to take over for the simulator. In this thesis a regression model proxy is being built to replace the need for reservoir simulations and to help optimize the injection scenario.Creating a proxy requires a thorough understanding of the injection process and many simulations has to be conducted. To reduce the amount of simulations required the input parameters can be scaled dimensionless. Still there are many simulations required to generate enough data for the proxy to use. The process can be simplified by writing computer scripts to automate simulations and generation of the proxy. Results prove that it is possible to create a regression model proxy for CO2 injection scenarios and to use it to find an optimal injection scenario.
7
Mahzari, Pedram. "Prevention of CO2 leakage from underground storage reservoirs." Thesis, Heriot-Watt University, 2016. http://hdl.handle.net/10399/3152.
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8
Watson, Francesca Elizabeth. "Numerical simulation of CO2 storage in saline aquifers." Thesis, Durham University, 2015. http://etheses.dur.ac.uk/11189/.
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CO2 capture and storage (CCS) has been proposed as a climate change mitigation strategy. The basic principle is to prevent CO2 which would normally be emitted from large point sources, such as power stations, from entering the atmosphere. This is achieved by capturing the CO2 at source and storing it in a location where it will be trapped and unable to enter the atmosphere. This work looks specifically at geological storage of CO2 in deep saline formations. Dynamic simulations can be used to investigate the fundamental physical and chemical processes which occur when CO2 is injected into geological formations. They can also be used to determine the suitability of a particular site for CO2 storage. The scale of the processes being simulated is important when building a dynamic model. Here dynamic simulations have been used to explore three different aspects of geological CO2 storage in deep saline formations. The first model investigates large scale CO2 migration and pressure build up at a potential CCS site. The second model concentrates on the small scale processes of CO2 dissolution and convection. The third model attempts to accurately model both the large scale processes of CO2 injection and migration and the small scale processes of CO2 dissolution and convection. Dynamic simulations have been used to model storage capacity, CO2 migration and pressure buildup at a potential CO2 storage site in the UK North Sea. There are large uncertainties in the input data so various models have been run using a range of parameters. The primary control on pressure buildup at the site is the permeability of the unit directly beneath it. The plume diameter is primarily controlled by the porosity and permeability of the reservoir unit. Despite uncertainties in the input data, the use of a full three-dimensional (3D) numerical simulation has been extremely useful for identifying and prioritizing factors that need further investigation. Dissolution of CO2 into existing formation waters (brine) leads to an increase in brine density proportional to the amount of dissolved CO2. This can lead to gravitational instabilities and the formation of convection currents. Convection currents, in turn, will increase CO2 dissolution rates by removing CO2 saturated brine from the CO2-brine interface. The dissolution and subsequent convection of CO2 which has leaked through a fracture is investigated using dynamic simulations. The instigation of convection currents due to flow through a fracture increases dissolution rates. Comparison of our results with fracture flow rates shows that for typical fracture apertures dissolution from a fracture is small relative to the amount of CO2 flowing through the fracture. Two phase flow effects and the currents caused by an advancing plume of injected CO2 can affect patterns of CO2 dissolution and convection within a reservoir. Most existing models of CO2 dissolution and convection use a static boundary layer or do not involve two phase flow effects. A radial, two phase, two component model has been built to model the injection process along with convection enhanced dissolution. The model performs well compared to analytical solutions in terms of the large scale processes of CO2 migration and pressure buildup but modelled convection is highly dependent on grid resolution. Numerical instabilities are also present. Further work is needed to increase the accuracy of the model in order to allow higher resolution modelling to be carried out and modelling of the smaller scale processes to be improved.
9
Killerud, Marie. "Comparison of Dry Gas Seasonal Storage with CO2 Storage and Re-Use Potential." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for petroleumsteknologi og anvendt geofysikk, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-22789.
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To make large-scale CO2 storage economic, many groups have proposed using CO2in EOR projects to create value for CO2 storage. However, CO2 EOR projectsgenerally require a large and variable supply of CO2 and consequently may requiretemporary storage of CO2 in geological formations. In order to store CO2 atoffshore sites as a source for CO2 EOR projects, the CO2 needs to be extractedfrom a storage site to a certain extent. Alternatively, CO2 EOR projects maybe developed alongside saline aquifer CO2 storage with only some of the CO2being used for EOR. The idea of temporary storage of CO2 may therefore be akey part of the solution for today?s climate challenge regarding CO2 emissions.Seasonal storage of dry methane gas is a well-established technique, and based onthis project, it can also work for CO2. This project examines the effectiveness ofgeological storage and re-use of CO2 compared to seasonal dry gas storage. Thecontrols on injection and production of CO2 from an ideal storage geological siteis estimated.
10
Ülker, Emine Buket [Verfasser]. "Investigation of the CO2 storage capacity of aquifer struktures : CO2 storage in a Buntsandstein prototype aquifer / submitted by Emine Buket Ülker." [Clausthal-Zellerfeld] : [Univ.-Bibliothek], 2009. http://d-nb.info/993354580/34.
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11
Bilsbak, Vegard. "Conditioning of CO2 coming from a CO2 capture process for transport and storage purposes." Thesis, Norwegian University of Science and Technology, Department of Energy and Process Engineering, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9943.
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12
Gunnarsson, Niklas. "3D modeling in Petrel of geological CO2 storage site." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-162124.
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If mitigation measures are not made to prevent global warming the consequences of a continued global climate change, caused by the use of fossil fuels, may be severe. Carbon Capture and Storage (CCS) has been suggested as a way of decreasing the global atmospheric emission of CO2. In the realms of MUSTANG, a four year (2009-2013) large-scale integrating European project funded by the EU FP7, the objective is to gain understanding of the performance as well as to develop improved methods and models for characterizing so- called saline aquifers for geological storage of CO2. In this context a number of sites of different geological settings and geographical locations in Europe are also analyzed and modeled in order to gain a wide understanding of CO2 storage relevant site characteristics. The south Scania site is included into the study as one example site with data coming from previous geothermal and other investigations. The objective of the Master's thesis work presented herein was to construct a 3D model for the south Scania site by using modeling/simulation software Petrel, evaluate well log data as well as carry out stochastic simulations by using different geostatistical algorithms and evaluate the benefits in this. The aim was to produce a 3D model to be used for CO2 injection simulation purposes in the continuing work of the MUSTANG project. The sequential Gaussian simulation algorithm was used in the porosity modeling process of the Arnager greensand aquifer with porosity data determined from neutron and gamma ray measurements. Five hundred realizations were averaged and an increasing porosity with depth was observed. Two different algorithms were used for the facies modeling of the alternative multilayered trap, the truncated Gaussian simulation algorithm and the sequential indicator simulation algorithm. It was seen that realistic geological models were given when the truncated Gaussian simulation algorithm was used with a low-nugget variogram and a relatively large range.<br>Den antropogena globala uppvärmningen orsakad av användandet av fossila bränslen kan få förödande konsekvenser om ingenting görs. Koldioxidavskiljning och lagring är en åtgärd som föreslagits för att minska de globala CO2-utsläppen. Inom ramarna för MUSTANG, ett fyra år långt (2009-2013) integrerande projekt finansierat av EU FP7 (www.co2mustang.eu), utvecklas metoder, modeller och förståelse angående så kallade saltvattenakviferers lämplighet för geologisk koldioxidlagring. En del av projektet är att analysera ett antal representativa formationer i olika delar av Europa för att få kunskap angående förekommande koldioxidlagringsspecifika egenskaper hos saltvattenakviferer. Ett av områdena som har inkluderats är i sydvästra Skåne. Syftet med detta examensarbete var att konstruera en 3D modell över detta område med hjälp av modellerings/simuleringsprogrammet Petrel, utvärdera borrhålsdata samt genomföra stokastiska simuleringar med olika geostatistiska algoritmer och utvärdera dem. Målsättningen var att konstruera en modell för CO2 injiceringssimuleringar i det forstsatta arbetet inom MUSTANG-projektet. En algoritm av sekventiell Gaussisk typ användes vid porositetsmodelleringen av Arnager Grönsandsakviferen med porositetsdata erhållen från neutron- och gammastrålningsmätningar. Ett genomsnitt av femhundra realisationer gjordes och en porositetstrend som visade en ökning med djupet kunde åskådligöras. Två olika algoritmer användes vid faciesmodelleringen av den alternativa flerlagrade fällan: en algoritm av trunkerade Gaussisk typ och en sekventiell indikatorsimuleringsalgoritm. Resultaten tyder på att en realistisk geologisk modell kan erhållas vid användandet av den trunkerande algoritmen med ett låg-nugget variogram samt en förhållandevis lång range.
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Aldi, Francesca. "Characterization of bogs and their role in CO2 storage." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23105/.
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This study aims at analyzing peatlands, specifically alpine peat bogs, and how climate change can affect the development of these environments. Therefore, it has been used a computer model (DigiBog), created by Baird et al. (2012), thanks to which it is possible to study peatland development over time. Once understood the model and verified its functionalities, we applied it to the selected case study, which is an Alpine peatland located near Misurina lake (Italy). In order to do so, we collected field measurements to constrain the model for the actual geometry of the study site, as well as soil samples to obtain soil properties used as inputs in the model. Meteorological data were provided by ARPAV, thanks to the presence of a meteorological station near the Misurina lake. Finally, to understand how climate change may affect the development of this type of environments, we consider the forecasts of the Euro-Mediterranean Center on Climate Change (CMCC), with Representative Concentration Pathways (RCP) of 8.5. This scenario, in fact, which is the worst-case scenario provided by the IPCC (International Panel on Climate Change), appears to be the most realistic, because today other scenarios are outdated, given the current conditions of emissions and mitigation (Schwalm, 2020). In order to give a better context to the work done, a general description of the peat bogs and their importance from the climatic point of view was first introduced; then DigiBog, with which the maps were created, was described in detail. It is clear that the study of peatlands is fundamental, because it allows to understand how they can develop under specific conditions, and how they will adapt to future
climate scenarios worldwide. From the outputs obtained through DigiBog it is possible to understand that the model is able to represent in a fairly true way the real growth of the peatland, therefore it can be considered a valid tool to obtain data on the development of peatlands.
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Gharbi, Oussama. "Fluid-rock interactions in carbonates : applications to CO2 storage." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/24928.
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It is well established that more than half of the world's hydrocarbon reserves are contained in carbonate reservoirs. In a global context, which is characterized by an increasing demand in energy, population growth and overall economic development, it is very important to unlock potential carbonate resources while mitigating the effects of climate change. Moreover, significant volumes of carbon dioxide - the major greenhouse gas contributor to global warming - can be stored in carbonate subsurface formations such as carbonate depleted reservoirs and deep saline aquifers. Therefore, better understanding of carbonate porous media has a wide range of major industrial and environmental applications. However, because of complex pore structures, including the presence of micro-porosity, heterogeneities at different scales, combined with high chemical reactivity, it remains very challenging to describe flow and transport in carbonates. In this thesis, we focus on carbonate porous media and aim to better describe flow, transport and reaction in them. The main application of this work is related to carbon storage in deep saline carbonate aquifers. More particularly, we address fluid-rock interactions e.g. wettability alterations and reactive transport, that occur in carbonate formations. First, we investigate the impact of wettability alteration on multi-phase flow properties. We use pore-network modelling to analyze the impact of wettability alteration by modelling water-flood relative permeability for six different carbonate samples with different connectivity. Pore-scale multi-phase flow physics is described in detail and the efficiency of water-flooding in mixed-wet carbonates is related to the wettability and pore connectivity. We study six carbonate samples. Four quarry samples - Indiana, Portland, Guiting and Mount Gambier - and two subsurface samples obtained from a deep saline Middle Eastern aquifer. The pore space is imaged in three dimensions using X-ray micro-tomography at a resolution of a few microns. The images are segmented into pore and void and a topologically representative network of pores and throats is extracted from these images. We then simulate quasi-static displacement in the networks. We represent mixed-wet behaviour by varying the oil-wet fraction of the pore space. The relative permeability is strongly dependent on both the wettability and the average coordination number of the network. We show that traditional measures of wettability based on the point where the relative permeability curves cross are not reliable. Good agreement is found between our calculations and measurements of relative permeability on carbonates in the literature. The work helps establish a library of benchmark samples for multi-phase flow and transport computations. The implications of the results for field-scale displacement mechanisms are discussed, and the efficiency of waterflooding as an oil recovery process in carbonate reservoirs is assessed depending on the wettability and pore space connectivity. Secondly, we investigate at the laboratory column scale (50 cm), fluid-rock interactions that occur through the injection of an acidic solution into carbonate porous media. Laboratory columns are packed with crushed and sieved porous Guiting carbonate grains. Therefore a homogenous porous medium at the Darcy scale is created and the effect of micro-heterogeneities on transport and reactive transport properties is highlighted. We first conduct a series of passive tracer experiments. Salinity is used as a non-reactive tracer as brine is injected at a constant flow rate into columns pre-saturated with equilibrated deionised water. Solute breakthrough curves are experimentally obtained by measuring the conductivity of collected effluent samples. Subsequently, by solving the advection-dispersion equations using PHREEQC geochemical software, we compare the experimental measurements with numerical predictions of breakthrough curves. A good match is obtained for a dual porosity model and a dispersion coefficient is estimated. We then investigate reactive transport by injecting at constant flow rate acidic brine (hydrochloric acid diluted in saline brine with an overall pH of 3) into columns pre-saturated with equilibrated brine. We measure the effluent concentrations using ICP-AES (inductively coupled plasma atomic emission spectroscopy) Moreover; scanning electron microscopy (SEM) is used to determine single grain-scale changes. We assess the impact of flow rate on the resident time distribution of solutes and reaction profiles along the columns. We discuss challenges encountered regarding the reproducibility of the results and we highlight the implications of such phenomenological studies on carbon storage in carbonates. Finally, we experimentally examine fluid-rock interactions that are induced by the injection of supercritical CO2 (sc-CO2) in carbonate formations at the pore scale. I designed and built a novel experimental apparatus that allows the injection of brine enriched with sc-CO2 at typical CO2 storage conditions. In our experiments the temperature is 500C and the injecting pressure is 9MPa. A novel methodology that combines pore-scale imaging, core flooding and pore-scale modelling is applied in the context of CO2-carbonate-brine interactions. We experimentally use a high pressure and temperature mixing vessel to generate brines enriched with sc-CO2.The mixture is then injected using high precision piston pumps at a constant flow rate (Q=0.1 ml/min) into carbonate micro samples (5 mm diameter and 20 mm length) saturated with pre-equilibrated high salinity brine. We measure the permeability changes in real time during the injection of reactive fluids, In addition, dry high-resolution micro-computed tomography scans are obtained prior to and after the experiments and the pore structure, connectivity and computed flow fields are compared using image analysis and pore-scale modelling techniques. We perform direct simulations of transport properties and velocity fields on the three-dimensional scans and we extract representative pore-throat networks to compute average coordination number and assess changes in pore and throat size distributions. Moreover, we assess the impact of reaction rate on reactive transport. We alter the reaction rate and hence the Damköhler number by under saturating the sc-CO2/brine mixture with crushed and sieved carbonate grains. Two regimes of dissolution are experimentally observed: dominant wormholing and a more uniform dissolution regime. High resolution 3D scans of the dissolution patterns confirm these observations. Permeability increases over several order of magnitude with wormholing whereas for the uniform dissolution, the increase in permeability is less pronounced. Overall, fewer pore and throats are present after dissolution while the average coordination number does not change significantly. Flow becomes concentrated in the wormhole regions after reactions although a very wide range of velocities is still observed. We then compare the observed results for single phase flow (wormholing induced by the injection of single phase brine saturated with sc-CO2) to two-phase flow reactive flow experiments (co injection of sc-CO2 and brine). Results show that wormholing is also seen in the two-phase experiments. Directions for future research in the area of fluid-rock interactions are then discussed.
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Maver, Marko. "Understanding governance and regulation of CO2 storage in Europe." Thesis, University of Sheffield, 2015. http://etheses.whiterose.ac.uk/10095/.
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Climate change, continued economic development, and energy security have become increasingly pressing issues over the past two decades or so. One potential solution to this interrelated problem is the idea to capture the carbon dioxide (CO2) from large stationary emission sources, such as power plants, and permanently store it deep underground. In this way CO2 emissions can be prevented from reaching the atmosphere, whilst allowing for a continued use of fossil fuels, until other alternatives (i.e. wind, solar, biomass) are developed on a wider scale. This process is also referred to as carbon capture and storage (CCS). The literature review in this thesis identifies the need to present a more in-depth picture of the entire process of governance of CO2 storage. The aim of this research is therefore to examine the extent to which the current legal and regulatory frameworks are able to mediate between managing the environmental risks of CO2 storage and the development/deployment of CCS in Europe. The analysis is underlined by the governance network theory (GNT), borrowing also elements from the theory of bounded rationality. Along with an extensive doctrinal legal scholarship, data analysis is also supported by 15 in-depth interviews with key CCS stakeholders in Europe. The results show that there is a wide consensus that the current legal and regulatory frameworks are robust enough, albeit the existence of uncertainty in regards to a number of legal provisions. There is also wide agreement between stakeholders in regards to the ability of operators to manage the environmental risks of CO2 storage. The discussion of these results show the applicability of the GNT as a framework for studying the management of environmental risks of CO2 storage, and the development and deployment of CCS technology in conjunction. Implications drawn from these findings also show that the management of environmental risks of CO2 storage and the future of CCS technology depends heavily on the effective relationship between the government agencies (i.e. competent authority) and project developers. Furthermore, good communication and engagement with other stakeholders, in particular the general public, will also be significant in the future development/deployment of CCS projects in Europe. When these relationships are good, this research argues that efficiency gains of governance are realised.
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Khudaida, Kamal. "Modelling CO2 sequestration in deep saline aquifers." Thesis, Loughborough University, 2016. https://dspace.lboro.ac.uk/2134/21104.
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In spite of the large number of research works on carbon capture and sequestration (CCS), the migration and behaviour of CO2 in the subsurface (i. e. strata below the earth's surface) still needs further understanding and investigations with the aim of encouraging the governmental policy makers to adopt CCS technology as one of the most viable means to tackle the global warming threats. In this research work, a series of numerical simulations has been carried out using STOMP-CO2 simulation code to determine the flow behaviour and ultimate fate of the injected supercritical carbon dioxide (scCO2) into saline aquifers in medium terms of storage (i. e. few thousand years). The characteristics of the employed simulator, including the mathematical algorithm, governing equations, equations of states and phase equilibria calculations are explained in details.
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Rustenberg, Karin Hveding. "X-ray Studies of Capture, Storage and Release of CO2." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for fysikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18889.
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We show experimentally that CO2 intercalates into the interlayer spaceof the synthetic smectite clay Li-fluorohectorite (LiFh). The intercalationoccurs for a range of conditions in terms of pressure (5 bar to 20 bar) andtemperature (-20'C to 5'C). The mean basal spacing of the clay layersin LiFh intercalated by CO2 is found to be approximately 12.0 Å.We observe that the dynamics depends on the pressure, with a higherintercalation rate at increased pressure. Even under pressure of 20 bar,intercalation of CO2 is slower than H2O intercalation in fluorohectoritesby orders of magnitude.In situ observations show that LiFh is able to retain CO2 in the interlayerspace at room temperature, and the CO2 only starts leaving the clay attemperatures exceeding 30'C. Hydrated and CO2-intercalated clays areindistinguishable by use of X-ray diffraction alone. The difference in behaviorat higher temperatures is used as an additional confirmation thatintercalation of residual water is not the cause of the observed swelling.Furthermore, we report a new intercalation state corresponding to intercalationof more than one layer of CO2 into the interlamellar space, andhave also observed changes in the intercalation state of a monohydratedLiFh sample under exposure to CO2.We believe that the findings, concerning both intercalation and deintercalation,could be relevant for application of clays related to capture, transportor storage of CO2.
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Amos, Daniel Michael. "High pressure hydrates of CO2 & materials for carbon storage." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/21031.
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The class of water-ice compound known as gas hydrate has been of interest to science for sometime where, for instance, gas hydrates make excellent candidates for studying the interactions of water and gas molecules. They are also of relevance to industry, where they present an interesting material for the separation, transport, and storage of different gases, and also due to the vast quantities of methane gas that are trapped in natural gas hydrate formations. While much is known about the behaviour of many gas hydrate systems at high-pressure, the CO2 hydrate system is less well studied, with apparent hydrate dissociation at just 10 kbar, and (prior to this work) an unsolved crystalline phase in the pressure range 6-10 kbar. In this work the CO2-H2O system has been studied at high-pressure and, by heating samples to the liquid state and observing their behaviour on refreezing, it has been confirmed that there are indeed no hydrate phases in the system above 10 kbar (up to at least 40 kbar). While performing this investigation, an interesting effect of CO2 on the behaviour of water crystallisation was also observed, and additionally, a simple yet effective technique for making solubility measurements in the system at high-pressure has been discovered. Using a combination of neutron and x-ray diffraction techniques, the crystal structure of the previously unsolved ‘HP’ CO2 hydrate phase has been determined by ab-initio methods. It has been found to be a new gas hydrate structure, but is shared by a small number of Zintl compounds, and may also be common to the unsolved C0 phase of H2 hydrate. The structure has a characteristic spiral of guest molecule sites, leading to its suggested label as the spiral hydrate structure (s-Sp). Its composition has been measured as a tri-hydrate, and the compressibility of s-Sp and the low-pressure s-I CO2 hydrate phases have also been measured. On cooling to 77 K it has been discovered that a third CO2 hydrate phase is formed with a significantly larger unit cell, which is thought to possess a structure similar to that of s-Sp, but with an ordered arrangement of CO2 molecules. Finally, a pilot study of the high-pressure behaviour of the binary H2-CO2 hydrate system has been performed. Using Raman spectroscopy it has been found that a new mixed hydrate phase exists in the pressure range 5-15 kbar, and it is speculated that this could exhibit a freely tunable H2/CO2 content, based on suspicion that it forms the s-Sp structure. Additionally, it has been found that H2 and CO2 chemically react at room temperature, when compressed to ~5 kbar in a rhenium gasket. From the Raman spectrum this reaction product has been identified to be aqueous-methanol.
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Suhett, Helmer Gisèle. "Crack propagation on rock mass on the CO2 storage context." Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1190/document.
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Le captage et stockage du CO2 (CSC) dans les formations géologiques profondes est une solution pour réduire les effets indésirables du CO2 atmosphérique. Les formations géologiques étant des milieux hétérogènes, contiennent souvent des réseaux de fissures. La ténacité (KC) est un paramètre de la roche associé à la capacité du matériau à résister la propagation d'une fissure. La propagation d'une fissure peut dériver du changement de l'état de contrainte ou du changement de la ténacité dû à la dégradation de la roche. La connaissance de la ténacité et son évolution due aux effets chimiques est donc importante pour la modélisation de la propagation des fissures dans le contexte de stockage géologique du CO2.Un objectif de ce travail est l'évaluation de la dégradation par le CO2 sur la ténacité d'une roche réservoir. Un calcaire (Pierre de Lens) est choisi pour être étudié dans son état sain et dégradé. La dégradation est réalisée dans un autoclave : les échantillons sont placés dans une solution aqueuse saturée en CO2, sous les conditions de réservoir (60°C et 15 MPa).Plusieurs configurations ont été choisies pour les essais mécaniques en mode I et en mode II. Certains essais ont été réalisés en utilisant une technique de corrélation d'images (DIC). Ce dispositif permet d'évaluer la ténacité à partir de l'évolution des champs de déplacements. Les résultats expérimentaux montrent que les valeurs de ténacité en mode I sont tout à fait concordantes entre les différents types d'essai. La technique de corrélation d'image met en évidence que la ténacité en mode II ne peut pas être évaluée dans les essais de chargement non confiné. Pour la procédure de dégradation, on peut constater par des analyses complémentaires que la porosité de la roche change peu (0,4 %). La ténacité de la roche n'est pas sensiblement affectée passant de 0,62 à 0,58 MPa.m0,5. On a également étudiée l'effet de la présence de l'eau par des essais de fracturation avec des échantillons saturés. Celle-ci a une influence plus significative avec une réduction d'environ 17% de la ténacité relatif aux échantillons secs. En ce qui concerne l'analyse en mode II (PTST), des essais ont été réalisés sous différentes pressions de confinement (5 - 15 MPa). On peut constater que cet essai permet une bonne évaluation en mode II (de l'ordre de 3 MPa.m0,5). Cependant, le mode I est encore présent pour les pressions de 5 et 10 MPa, et n'est pas toujours inexistant pour une pression de 15 MPa. On a montré, là encore, que l'influence de CO2 est faible avec une ténacité en mode II passant de 2,96 à 2,77 MPa.m0,5. L'influence de la dégradation de la roche par le CO2 sur la propagation de fissures a été étudiée à l'aide d'une modélisation numérique en utilisant le modèle ENDO-HETEROGENE, intégré dans le code de calcul Code-Aster®. Ce modèle est basé sur l'amorçage et la propagation des fissures dans un milieu hétérogène dont la variabilité des paramètres du matériau suit le modèle probabiliste de Weibull à 2 paramètres (m et σ0). On a exploré la possibilité que la dégradation chimique influence l'hétérogénéité de la microstructure. La modélisation montre que le paramètre m influence le nombre et la dimension des fissures, cependant, la taille maximale de la fissure ne varie pas avec m. Pour remettre ces résultats expérimentaux en contexte, les paramètres de Weibull sont évalués pour la roche saine et dégradée. On observe que m varie de 8,55 à 8,52 et σ0 de 2,8 et 2,2 MPa. Selon la simulation numérique cette variation n'est pas suffisante pour changer le réseau des fissures créées après un chargement dans une couche géologique. Ces résultats montrent que dans le cas d'un réservoir calcaire l'injection de CO2 n'influe pas significativement ni le paramètre ténacité, ni dans les paramètres probabilistes de la fracturation. Ces résultats correspondent à une période de 10 ans dans une zone du réservoir loin du puits d'injection<br>The capture and the storage of CO2 (CSC) on the underground geological formations is a solution for the CO2 undesirable effects reduction. The geological formations being composed by heterogenic material have a crack network. The fracture toughness (KC) is a rock parameter connected with the capacity of a material to resist crack propagation. The propagation of a crack can be due to the changing of the stress or to the rock degradation. The evaluation of the fracture toughness and its evolution due to the chemical effects is then important to the modelling of the crack propagations on the CO2 storage context. One objective of this work is the experimental evaluation of the CO2 degradation on the fracture toughness. For the experimental program a preliminary study was made to the choice of the rock and the test to be performed. In this way, a limestone (Pierre de Lens) was chosen to be studied in an intact and degraded state. The degradation takes place in an autoclave, where the samples are put at CO2-saturated water in reservoir conditions (60 °C and 15 MPa).Several experimental tests are chosen for the evaluation of the fracture toughness in modes I and II. Some examples are the Central crack Brazilian disc (CCBD) for the mode I and the Punch through shear test (PTST) for the mode II. Some tests where performed using an image correlation technique (DIC). This set-up allows the fracture toughness evaluation by the displacement field evolution. The experimental results shows the fracture toughness values obtained by the different configurations are in good agreement. After the DIC technique analysis we can point the fracture toughness in mode II can not be evaluated in a non confined test. For the degradation process, the complementary analysis in the mercury porosimeter shows the rock porosity changing is low (0.4 %). At the SEM, the degradation can be observed by a homogenization of the sample. For the fracture toughness it value passes from 0.62 to 0.58 MPa.m0.5. We also have studied the effect of water performing tests in a saturated environment. The influence is more significant with a reduction on 17 % in the fracture toughness. The CO2 presence in the fluid does not affect this value. Concerning the mode II evaluation by the PTST test, the samples were submitted to different confining pressures (5, 10 and 15 MPa). We can observe a good evaluation of the fracture toughness in mode II (around 3 MPa.m0.5). Nevertheless, the mode II is still present for the pressures 5 and 10 MPa, and it is not inexistent for a 15 MPa pressure. Still in this case the influence of CO2 is low with values passing from 2.96 to 2.77 MPa.m0.5.The influence if the rock degradation by the CO2 presence on the crack propagation were studied by the help of a numerical model ENDO-HETEROGENE, that is present in the Code-Aster® calculation code. This model is base on the initiation and propagation of cracks in a heterogenic environmental where the parameter variability follows the 2 parameters Weibull probabilistic model (m and σ0). We exploited the possibility of the chemical degradation influence on the microstructure heterogeneity that is represented by the parameter m. The model shows that the changing of m influence on the crack number and dimensions by the maximum size of the crack didn't change. Putting this result in context, the Weibull parameters were evaluated for the intact and degraded rock. We observed that m changes from 8.55 to 8.52 and σ0 from 2.8 to 2.2 MPa. The numerical simulations show this variation is not enough to change the crack network that is formed after a load in a geological layer. The general results show that for a limestone reservoir the CO2 injection affect significantly neither the fracture toughness nor the probabilistic parameters. These results correspond to a 10 years period for a zone far from the injection point
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Erlandsson, Jennifer, and Fredrik Tannoury. "Climate Footprint on Transportation and Storage of Carbon Dioxide (CO2)." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-281757.
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In order to combat climate change there is a need to achieve negative emissions. Bio-energy with carbon capture and storage (BECCS) is a promising technology that offers the possibility to remove carbon dioxide (CO2) emissions from the atmosphere. However, this also implies that the BECCS process needs to store more CO2 than it emits. The purpose of this study is to examine the liquefaction, intermediate storage, transportation and long term storage of CO2 and evaluate the climate impact of the energy use and the leakage of CO2. This thesis is based on data collected through an extensive literature study and several interviews that were performed with relevant actors and informants. A key finding in this thesis is that the energy use through the examined steps of BECCS is responsible for the bulk of the CO2 emissions. Liquefaction and the transportation plays an essential role as it has the highest energy usage. Unfortunately the energy use of injecting CO2 into the geological formation remains unknown because of lack of data. The leakages found throughout the process were often negligible or even zero. However the leakages from injecting CO2 through pipeline and the CO2 leakage from long term storage was found to be of some significance. The total BECCS related carbon dioxide equivalent (CO2e) emissions, are summarised in three scenarios ranging from approximately 49-58 kg CO2e per stored tonne of CO2. In these scenario calculations, some assumptions have had to be made. In order to evaluate the true and total environmental impact of BECCS, further research will be needed.<br>Dagens samhälle står inför avsevärda miljömässiga utmaningar, inte minst då mängden växthusgaser (GHG) i atmosfären kommer behöva reduceras drastiskt för att undvika två graders uppvärmning. Bio-energy with carbon capture and storage (BECCS) är en teknologi med potential att avlägsna koldioxid (CO2) inte bara från nya utsläpp, utan även i bästa fall från atmosfären. I det specifika fall som denna rapport tittar närmare på, förbränns biomassa för att skapa fjärrvärme, men istället för att CO2 släpps ut i luften så fångas den upp och komprimeras till flytande form. Därefter kan CO2 transporteras till en injektionsanläggning för att slutligen pumpas ner i en geologiskt lämplig berggrund. Denna process kan resultera i negativa utsläpp om mer CO2 lagras än vad processen skapar och släpper ut. Målet med detta kandidatexamensarbete är att undersöka energianvändningen och läckaget av CO2 under förvätskningen, den kortsiktiga lagringen, transporten samt den långsiktiga lagringen av CO2. Kandidatexamensarbetet är framförallt baserat på data insamlad i form av en litteraturstudie. Denna data har även kompletterats med data från flertalet intervjuer med forskare och anställda på företag som arbetar med BECCS. Flera antaganden har varit nödvändiga då det i dagsläget finns en brist på information angående energianvändningen och läckaget av CO2 i processens delsteg. Energianvändningen för injektionen av CO2 förblir okänd då det inte fanns någon relevant information att tillgå. Då läckaget visade sig vara försumbart eller noll i flera delsteg, utgör energianvändningen en signifikant andel av de totala utsläppen. De största utsläppen av CO2 inom ramen för BECCS processen orsakas därför av förvätskningsprocessen och transporten av CO2 då dessa delar är mest energikrävande. Resultatet av kandidatexamensarbetet kan sammanfattas i tre scenarion, ett lågt scenario, ett median scenario och ett högt scenario. Slutsatsen var att samtliga inkluderade steg av BECCS resulterar i ett utsläpp mellan 49-58 kg koldioxidekvivalenter (CO2e) per ton CO2 som lagras. För att kunna kvantifiera den totala klimatpåverkan av BECCS finns ett behov av ytterligare studier som tar hänsyn till alla delsteg under processen.
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Kilpatrick, Andrew David. "Fluid-mineral-CO2 interactions during geological storage of carbon dioxide." Thesis, University of Leeds, 2014. http://etheses.whiterose.ac.uk/8889/.
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In order utilise geological carbon dioxide storage (GCS) at an industrial scale predictions of reservoir scale behaviour, both chemical and physical must be made. In order to ground-truth the geochemical data underlying such predictions, laboratory experiments at temperatures and CO2 pressures relevant to GCS are essential. Mineral dissolution rate, CO2 solubility and pH data has been collected from batch experiments carried out on quartz, K-feldspar, albite, calcite, dolomite and Sherwood Sandstone materials. These experiments were designed to assess the influence of a variety of factors on dissolution rates: changes in grain size from 125μm - 180μm to 500μm - 600μm; changes in fluid composition from deionised water to 1.36M NaCl solution; changes in CO2 pressure from 4 bar to 31 bar; changes in temperature from 22°C to 70°C. Experiments carried out on the Sherwood Sandstone material also included work on consolidated rock, rather than the powder used in other experiments. Calculated dissolution rates for silicates were found to agree well with values calculated from literature-sourced dissolution equations and the USGS-produced general rate equation (USGS 2004) was found to be suitable for predicting these rates. Calculated dissolution rates for the carbonate minerals was found to be strongly retarded due to transport effects, with literature-sourced equations significantly over-predicting dissolution rates. Dissolution of the sandstone material was found to be dominated by K-feldspar and dolomite dissolution, rates of which compare favourably with those obtained from the single mineral experiments. A significant increase in porosity was observed in the core flow-through experiment, associated with dolomite dissolution. Several experiments were carried out using a Hele-Shaw cell in order to visualise the formation and migration of density plumes which form as CO2 dissolved into unsaturated fluids. Introduction of NaCl and decreases in permeability were found to significantly retard migration of CO2 saturated fluid, while minor heterogeneities in the cells served to focus and accelerate plume movement. Modelling work suggests that predictive models currently underestimate the rapidity of formation and migration of these plumes.
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Ogaya, Garcia Xènia. "Magnetotelluric characterisation and monitoring of the Hontomín CO2 storage site, Spain." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/284957.
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The electromagnetic methods are especially interesting for the characterisation and monitoring of geological storage of CO2 sites. The electrical resistivity is a physical parameter that depends on the mineralogical composition of the rocks, as well as on other characteristics such as porosity, pore connectivity, pore fluid salinity, saturation, temperature and pressure. The CO2 injected in the reservoir produce changes in the resistivity that enables its detection with electromagnetic methods.
However, it is necessary to have a thorough knowledge of the structure at the pre-injection state to detect and quantify the changes produced by the injected CO2. The magnetotelluric method is the only electromagnetic method with a penetration depth ranging from ten of metres to hundreds of kilometres depth. Furthermore, this method allows determining the directionality and evolution of the structures in depth thanks to its tensorial character.
Hence, the objective of this thesis is to characterise using the magnetotelluric method, the Technological Development Plant (TDP) of Hontomín for Geological Storage of CO2 in a deep saline formation and evaluate the capabilities of the magnetotelluric method to monitor the injected gas.
The work presented in this thesis represents an important contribution to the characterisation projects of CO2 storage sites in deep saline formations. The 3D resistivity model obtained defines the reference geoelectrical model for the subsequent electromagnetic monitoring studies. Moreover, the model shows the dome structure of Hontomín and the main fault system. The model allows identifying the potential leakage zones and defines the monitoring needs for the Hontomín TDP. This model also correlates satisfactorily with hydrogeochemical, seismic, gravimetric and well-log data. Additionally, the monitoring capabilities of the magnetotelluric method have been assessed in this work, proposing a new methodology to improve the resolution of the surface magnetotelluric responses to resistivity changes occurred at the reservoir level.<br>La captura y almacenamiento geológico de dióxido de carbono (CO2) constituye una de las soluciones tecnológicas propuestas en la actualidad para reducir las emisiones de este gas a la atmosfera. El objetivo de esta tecnología es capturar y transportar el gas desde los grandes focos emisores hasta los lugares seleccionados como almacenes geológicos, donde es inyectado. Esta tesis se centra en la Planta de Desarrollo Tecnológico (PDT) de Hontomín (España), donde el almacenamiento geológico se llevará a cabo en un acuífero salino profundo. La PDT se enmarca en el proyecto Compostilla OXYCFB300, dentro del Programa Energético Europeo para la Recuperación (European Energy Programme for Recovery).
La mayoría de las propiedades físicas de la roca almacén, en especial la resistividad eléctrica, variarán tras la inyección de CO2. El fluido salino conductor contenido en el poro será sustituido por el gas, de carácter más resistivo, reduciendo el volumen de agua disponible para la conducción iónica. Por ello, los métodos electromagnéticos, sensibles a la resistividad eléctrica, son especialmente interesantes para este tipo de proyectos ya que permiten estudiar la evolución del gas inyectado y estimar la saturación de CO2 en el poro.
Esta tesis tiene por objetivo la caracterización, control y seguimiento de la PDT de Hontomín mediante el método magnetotelúrico. El objetivo principal es la obtención de un modelo geoeléctrico tridimensional (3D) de referencia, que permita caracterizar la zona en la situación de preinyección y sirva de modelo base para los posteriores estudios de seguimiento con métodos electromagnéticos de fuente controlada. Asimismo, esta tesis persigue evaluar la capacidad de control y seguimiento del método magnetotelúrico. Con este propósito, se ha desarrollado una nueva metodología para mejorar la resolución de las respuestas magnetotelúricas superficiales a cambios de resistividad producidos en el reservorio (metodología denominada layer stripping).
La caracterización de la PDT de Hontomín se ha llevado a cabo en dos etapas. En la primera etapa se adquirió un perfil magnetotelúrico de orientación NS. Este primer estudio demostró la idoneidad del método para caracterizar la zona de estudio y proporcionó un modelo geoeléctrico bidimensional (2D) de la misma. En la segunda etapa se completó la adquisición de los datos, lo que permitió la obtención del modelo geoeléctrico 3D de la PDT. Esta tesis presenta ambos estudios de caracterización. Cada uno de ellos es justificado por un análisis previo de dimensionalidad de los datos y detalla la metodología de inversión empleada para alcanzar resultados válidos y apropiados.
El modelo 2D obtenido previamente ha sido validado por el modelo 3D, el cual se correlaciona satisfactoriamente con datos hidrogeoquímicos, sísmicos, gravimétricos y datos de pozos, entre otros. Este modelo 3D constituye el modelo geoeléctrico de referencia de la PDT, siendo la principal contribución de esta tesis. El modelo muestra la estructura de domo de Hontomín y los principales conjuntos de fallas. Permite así identificar las posibles zonas de fuga y definir las necesidades de control y seguimiento de la PDT.
De este modo, esta tesis supone una importante contribución a los proyectos de caracterización de almacenes de CO2 en acuíferos salinos profundos. El método magnetotelúrico ha demostrado ser una técnica electromagnética apropiada para caracterizar el área de estudio. Los resultados obtenidos son significativos y ponen de manifiesto la importancia de establecer un modelo geoeléctrico de la situación de preinyección a fin de caracterizar la estructura, concretar las necesidades de control de la planta y definir el modelo de referencia para los posteriores estudios de seguimiento. Los estudios electromagnéticos son complementarios a estudios de caracterización sísmicos y dada su sensibilidad a la conductividad eléctrica, se establecen como métodos de resolución superior para determinados aspectos de interés en el almacenamiento de CO2 y su seguimiento a largo plazo.
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Seevam, Patricia. "Transporting the next generation of CO2 for carbon capture and storage." Thesis, University of Newcastle upon Tyne, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.658037.
Full textAbstract:
Climate change has been attributed to greenhouse gases with carbon dioxide (C02) from power plants being the major contributor. Governments and industry worldwide are now proposing to capture CO2 from their power plants and either store it in depleted reservoirs or saline aquifers ('Carbon Capture and Storage', CCS), or use it for 'Enhanced Oil Recovery' (EOR) in depleting oil and gas fields. The research reported will have significant implications on the feasibility for future CO2 transportation for CCS. The United States has over 30 years experience with the transportation of carbon dioxide by pipeline, mainly from naturally OCCUlTing, relatively pure CO2 sources for onshore EOR. CCS projects differ significantly from this past experience as they will be focusing on anthropogenic sources from major polluters such as fossil fuel power plants. The fossil fuel power plants will produce CO2 with varying quality/purity of CO2 depending on the capture technology used. It was concluded that power plant impurities such as Ar, SOx and NOx have never been transported before and that gaseous transportation of C02 should be considered as an option in the .early stages of CO2 deployment. Application of current design and operational procedures to the new generation pipelines may not be deemed feasible due to the effect of anthropogenic CO2 on pipeline hydraulics. This could potentially yield an unsafe pipeline facility, with excessive investment and operating cost. In particular, the presence of impurities has a significant impact on the physical properties of the transported CO2 which affects: pipeline design; compressor/pump power, repressurisation distance and pipeline capacity. The effect of impurities on C02 is generally to raise the critical pressure and increase the two-phase region. An increase in the critical pressure and two-phase area reduces the operating flexibility of the pipeline. Large temperature and pressure drops are associated with the operating pressures and temperatures in the pipeline in the region of two-phase flow. Another alternative being considered for C02 transportation is the re-use of existing pipeline infrastructure. However, it has been identified that some limitation exists due to the operating parameters of these pipeline such as the maximum allowable operating pressure (MAOP), integrity and also the design capacity. Therefore, gaseous transportation may prove to be more feasible in these cases. Nevertheless, in order to meet emission targets, supercritical transport will be required, as it is able to transport the required amount of CO2 in order to meet emission targets due to the size of the infrastructure required. All these effects will have to be carefully considered as it has direct implications for both the technical and economic feasibility of developing a carbon dioxide pipeline infrastructure both in the UK and internationally. Transient power plant operation will lead to changes in the CO2 produced. Therefore, the transportation system must be designed to handle these changes in flow and options such as linepacking should be considered. It has been shown that linepacking gaseous pipelines are more feasible than operating supercritical CO2 pipelines. Therefore, venting needs to be considered as a potential option for supercritical CO2 pipelines. This could in turn incur additional costs due to potential regulatory requirements.
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Sergienko, Ekaterina. "Adapted reservoir characterization for monitoring and uncertainty analysis of CO2 storage." Toulouse 3, 2012. http://thesesups.ups-tlse.fr/2019/.
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L'analyse de risques du stockage géologique de CO2 consiste à simuler la dynamique du processus de stockage et à évaluer la probabilité de fuites. L'approche proposée dans ce travail consiste à utiliser des surfaces de réponses basées sur les processus Gaussiens, cela permet de réduire le grand nombre d'appels au simulateur de réservoir nécessaire à cette analyse. Dans cette thèse des méthodes innovantes sont étudiées pour résoudre les problèmes suivants: 1. Emplacement des puits d'injection 2. Estimation de la fiabilité 3. Analyse de sensibilité fiabiliste Pour résoudre le premier problème nous proposons une méthode de surface de réponse pour gérer les paramètres discrets (positions des puits) et les sorties fonctionnelles discrètes (évolution de pression du réservoir). Par ailleurs, nous introduisons une nouvelle méthode pour la modélisation des réponses variées dans le temps. Pour cela, la caractérisation des courbes est effectuée en utilisant des modèles à forme invariante. Pour le problème de fiabilité, nous avons développé une approche combinant la méthode de réduction d'ensemble et le krigeage. Un échantillonnage adaptatif est construit afin d'améliorer itérativement l'estimation de la probabilité de défaillance du modèle. Pour répondre au dernier problème, nous proposons une méthode pour l'analyse de sensibilité fiabiliste. Elle est basée sur une perturbation de la distribution de probabilité des variables d'entrée afin de trouver les facteurs qui contribuent le plus à la variabilité de la probabilité de défaillance. Toutes les méthodes proposées ont été testées numériquement sur des exemples analytiques et des cas test de stockage de CO2<br>Risk analysis of CO2 geological storage involves the simulation of the dynamics of the storage process and the evaluation of the probability of the possible leakage events. The approach followed here focuses on Gaussian Process response surface modelling in order to reduce the number of calls to the expensive reservoir simulator. Three major problems related to uncertainty analysis of CO2 storage are addressed: 1. Injection well placement 2. Reliability estimation 3. Reliability sensitivity analysis To tackle the first problem we provide a response surface method to handle discrete parameters (well positions) and discrete functional outputs to treat responses varying trough time (reservoir pressure evolutions). In addition, we introduce a new method for modelling functional outputs based on curves characterization and involving shape invariant model. To address the reliability problem, we introduce a subset simulation algorithm linked with the Gaussian Process model. It involves adaptive experimental design refinement and the model updating. To solve the last problem we suggest a new method for reliability sensitivity analysis. It is based on a perturbation of a probability distribution of input variables in order to evaluate which one contributes the most in the variability of the failure probability. All the proposed methods have been numerically tested on analytical and CO2 storage examples
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Evar, Benjamin. "Epistemologies of uncertainty : governing CO2 capture and storage science and technology." Thesis, University of Edinburgh, 2014. http://hdl.handle.net/1842/9977.
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This thesis progresses from a ‘science and technology studies’ (STS) perspective to consider the ways that expert stakeholders perceive and communicate uncertainties and risks attached to carbon dioxide (CO2) capture and storage (CCS) research and development, and how this compares with policy framings and regulatory requirements. The work largely falls within the constructivist tradition in sociology, but also draws on literature from the philosophy of science and policy-‐oriented literature on risk and uncertainty. CCS describes a greenhouse gas (GHG) mitigation technology system that involves the capture, pressurisation, transportation, geological injection and long-‐term storage of CO2 as an alternative to atmospheric emissions. Only few and relatively small applications exist at the moment and research efforts are on going in many countries. The case for developing CCS towards large-‐scale, commercial deployment has largely been presented as follows since the mid-‐ 1990s: climate change mitigation is the developed world’s historical responsibility and must be addressed urgently; chief amongst GHGs is CO2, which makes up more than three quarters of emissions; the vast majority of CO2 is emitted from the combustion and gasification of hydrocarbons – oil, gas and coal – for energy generation; transitioning away from these high-‐CO2 primary energy sources will likely take several decades at the least; therefore, CO2 capture systems should be designed for power and industrial emissions in developed countries, as well as emerging economies where energy suppliers will continue to construct relatively cheap and well understood high-‐CO2 generation plants. The development of large-‐scale CO2 capture has thus arisen from a concern with engineering a technological system to address a CO2 legacy in the developed world, and a high-‐CO2 trajectory in developing/emerging countries, rather than on the back of purely scientific curiosity. And the potential for large-‐scale development has been presented on the back of a variety of scientific and technical evidence, as well as the urgency of the policy objective and related aims. Research activities, often concentrated around technology demonstration projects, are the primary focus of the first part of this thesis. In the second part I consider the extent to which research has shaped policy developments, and how regulations have subsequently informed a more detailed research agenda. I follow a ‘grounded theory’ methodology as developed by Glaser and Strauss (1967) and take additional guidance from Glaser’s (1992) response to Strauss’ later writings as well as Charmaz (2006) and Rennie (2000), and use a mix of qualitative and quantitative analytical methods to assess my data. These include information from 60 semi-‐structured interviews with geoscientists and policy stakeholders; close readings of scientific publications, newspaper articles, policies and regulatory documents; statistical evidence from a small survey; quantitative analysis of newspaper articles; and social network analysis (SNA) of scientific co-‐authorship networks. Theory is drawn from STS literature that has been appropriate to address case study materials across each of the 7 substantive chapters. The first section of the thesis considers expert claims, with a focus on geoscience research, and draws on literature from the closely related ‘social shaping of technology’ (SCOT) and ‘sociology of scientific knowledge’ (SSK) programmes, as well as Nancy Cartwright’s philosophy of science. The second half of the thesis draws on the ‘co-‐production’ framework and Wynne’s (1992) terminology of risk and uncertainty, to assess relations between risk assessment and risk management practices for CCS. I likewise draw on literature from the ‘incrementalist’ tradition in STS to ask whether and how understandings of technology risk, governance and deployment could be improved. Each chapter presents new empirical material analysed with distinct reference to theories covered in the introduction. Chapter 2 provides a general overview of the history, technology, economics and key regulatory issues associated with CCS, which will be useful to assess the theoretically driven arguments in subsequent chapters. Chapter 3 draws on the concept of ‘interpretive flexibility’ (Pinch and Bijker 1984) to assess a range of expert perceptions about uncertainties in science, technology and policy, and I develop a substantive explanation, ‘conditional inevitability’, to account for an epistemic tension between expressions of certitude and the simultaneous acknowledgement of several uncertainties. Chapter 4 continues the enquiry into stakeholder perceptions and draws on Haas’ notion of ‘epistemic communities’ (Haas 1992) to assess geoscientists’ work practices. I complement this framing with a close look at how uncertainty is treated in simulation modelling and how conclusions about storage safety are formulated, by drawing on Nancy Cartwright’s philosophy of science (Cartwright 1999) and Paul Edwards’ account of complex system modelling for climate change (Edwards 2010). The chapter shows how shared understandings of adequate evidence and common analytical tools have been leveraged to present relatively bounded and simple conclusions about storage safety, while geoscientists nevertheless recognise a high degree of uncertainty and contingency in analyses and results. Chapter 5 continues the focus on knowledge production in the geosciences and is supported by SNA data of workflow patterns in the Sleipner demonstration project. The analysis shows how a few actors have had a pivotal role in developing insights related to storage safety particularly on the back of seismic monitoring and other data acquired through industry partnerships. I therefore continue the chapter with a deconstruction of how seismic data has been used to make a case for the safety of CO2 storage, again drawing on Cartwright and others (Glymour 1983) to explain how individual findings are ‘bootstrapped’ when conclusions are formulated. I show how a general case about storage safety has emerged on the back of seismic data from Sleipner as well as a shared understanding among geoscientists of how to account for uncertainties and arrive at probable explanations. Chapter 6 considers to what extent scientific research has given shape to, and in turn been shaped by, CCS policy and regulations in the EU, drawing on Wynne’s (1992) terminology of risk and uncertainty as well as legal scholarship (Heyvaert 2011). I conclude that a ‘rational-‐instrumental’ interpretation of uncertainty and precaution has furnished a compartmentalised understanding of risk assessment and risk management practices. Chapter 7 continues to look at the ways that risk assessment methodologies influence risk management practices through a case study of the Mongstad CCS demonstration project in Norway. I draw on ‘incrementalist’ literature (Lindblom 1979; Woodhouse and Collingridge 1993) to consider alternative conceptualisations of technology development and risk management when expectations clash with scientific uncertainties and criticism. Chapter 8 draws on insights from across STS (Downs 1972; Collingridge and Reeve 1986; Wynne 1992) to create a novel conceptual model that accounts for recent years’ developments in CCS governance. Here I conclude that setbacks and criticisms should be expected when analyses have largely presented CCS as a technical problem rather than a socially contingent system. Following Stirling (2010) I conclude that scientists and policymakers should instead strive to present complexity in their analyses and to engage with wider publics (Yearley 2006) when technical analysis is inseparable from socially mediated indeterminacies (Wynne 1992), to increase the chance of more successful engagement practices (Wynne 2006). The conclusions at the end of the thesis seek to draw out interpretive and instrumental lessons learned throughout.
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Alhajaj, Ahmed. "Multiscale design and analysis of CO2 capture, transport and storage networks." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/29477.
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CO2 capture, transport and storage (CCTS) is gaining a broad interest as a countermeasure to global warming. The systematic development of CCTS network infrastructure is a non trivial activity that involves choosing the optimum design of the selected CO2 capture plant technology and transportation mode, and identifying the key performance operating parameters and limiting uncertainties that need to be mitigated or optimized to ensure a safe cost-optimal network. This thesis focuses on developing a systematic multiscale modelling and optimization approach that integrates validated sub-process models of the MEA-based CO2 capture plant, compression train and pipelines in which thermodynamic properties were calculated using SAFT-VR with the supply-chain CO2 network model. A number of simulations were performed to analyse and identify the cost-optimal design and operating variables while considering different CO2 prices, flue gas bypass option and uncertainty in transporting flow temperature and composition. A meta model that combines the results of the fine scale model was then used in the supply chain network model to successfully determine the cost-optimal CCTS network for a case study in Abu Dhabi. A key result of the thesis was that the cost- optimal degree of capture is a function of several site-specific factors, including exhaust gas characteristics, proximity to transportation networks, adequate geological storage capacity, CO2 price, and the option to partially bypass flue gas. A higher CO2 price had a clear impact on encouraging higher degree of capture. The flue gas bypass option was seen to be an optimal option for lower than 60% degree of capture. It was also observed that transportation companies should levy a charge to discourage transporting flow from low CO2 content sources. This thesis serves to underscore the need to comprehend the science governing the behaviour at different scales and the importance of a whole-system analysis of potential CCTS networks.
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Syed, Shafiuddin Amer. "Permeability and injectivity enhancement of the near wellbore region fo CO2 enhanmced coalbed methane recovery and CO2 storage." Thesis, Imperial College London, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.534965.
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Mokhtari, Jadid Kahila. "Chemical Alteration Of Oil Well Cement With Basalt Additive During Carbon Storage Application." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613923/index.pdf.
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Capturing and storing carbon dioxide (CO2) underground for thousands of years is one way to reduce atmospheric greenhouse gases, often associated with global warming. Leakage of CO2 through wells is one of the major concerns when storing CO2 in depleted oil and gas reservoirs. CO2-injection candidates could be new wells, or old wells that are active, closed or abandoned.
To prevent the leakage, the possible leakage paths and the mechanisms triggering these paths must be examined and identified. It is known that the leakage paths can occur due to CO2-rock interaction and CO2-water-cement interaction.
Interaction between well cement and carbon dioxide has attracted much renewed interest because of its implication in geological storage of carbon dioxide. The diffusion of CO2-water through well cement is a long-term phenomenon which can take many thousand years. Partial pressure, porosity, permeability, cement type, moisture content and temperature are the factors that affect the carbonation of well cement. The objective of this research is to investigate the chemical reactions of the dissolved CO2 in the synthetic formation water with the plugs of well cement. Cement specimens were left in contact with CO2 saturated brine at 1100 psi and 65
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Qureshi, Jawwad Ashraf. "3D Processing of Seismic Data from the Ketzin CO2 Storage Site, Germany." Thesis, Uppsala universitet, Geofysik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-199583.
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The accumulation of CO2 in the atmosphere is considered to be the main reason for the global warming effect. The emissions can be reduced substantially by capturing and storing the CO2. The CO2SINK project was Europe’s first onshore project for the geological storage and monitoring of CO2. This project started operation near the town of Ketzin, Germany in the North East German basin in April 2004 and has continued as the CO2MAN project since April 2010. The main focus of the project was to develop the basis for Carbon Capture and Storage techniques by injecting CO2 and monitoring of CO2 in a saline aquifer in order to develop confidence for future geological storage of CO2 in Europe. In September 2004, a pilot seismic survey was performed in order to determine the necessary parameters for the conduction of a later 3D baseline seismic survey[i]. The pilot survey was performed along two perpendicular profiles near to the CO2 injection site. Pseudo 3D and 2D reflection seismic data were acquired. The results from 2D processing of the data contributed to planning of the 3D baseline survey. In this study the pseudo 3D data from the pilot seismic reflection survey is used to perform 3D processing for the first time. A significant part of the study is the correlation of results with the 3D baseline seismic survey and borehole data. All significant horizons, possible faults and traces of remnant gas were identified. Correlation with the 3D baseline, integration with the borehole data and time/depth contour maps showed good agreement with the 3D baseline survey and well log data. Low fold data, acquisition geometry, time shifts and source generated noise produces severe distortion in the data. Due to these limitations it was difficult to obtain good quality images. Careful processing that involved static corrections and more accurate velocity analysis were the key steps for successful imaging. These results were combined with bore-hole information for an integrated interpretation.
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Cadogan, Shane. "Diffusion of CO2 in fluids relevant to carbon capture, utilisation and storage." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/29434.
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In this work, molecular diffusion coefficients of carbon dioxide (CO2) in liquids relevant to carbon capture, utilisation and sequestration and enhanced oil recovery are reported. These parameters are necessary for the accurate and optimal design and control of such processes. Knowledge of these values is required to fully describe the migration of CO2 away from the injection wells and also for calculating the rate of absorption of CO2 into the formation fluids. However, diffusion coefficients are amongst the least studied of thermophysical properties, especially at high pressure, high temperature conditions. This work extended previous measurements where available, and produced new measurements where not, of diffusion coefficients at infinite dilution of CO2 in H2O, and several relevant brines and hydrocarbons at high temperatures (< 423 K) and high pressures (< 69 MPa). The Taylor dispersion method was used to determine diffusion coefficients for CO2 in water and selected hydrocarbons. The hydrocarbons chosen as representative of major crude oil components were n-heptane, nhexadecane, squalane, cyclohexane, and toluene. A technique based on nuclear magnetic resonance was used to measure effective diffusion coefficients of CO2 in several brines, encompassing monovalent and divalent salts, and a mixed brine. The diffusion coefficients of CO2 in water were correlated using the Stokes-Einstein equation in which the Stokes-Einstein number was assigned a value of 4 and the hydrodynamic radius was treated as a linear function of temperature. No relationship between brine salinity and the hydrodynamic radius was found. The results indicated pressure did not have an observable impact on the diffusivity in aqueous systems. The experimental uncertainty was found to be 2.3% with a coverage factor of 2 for the CO2-water system and 1.5% with a coverage factor of 2 for the CO2-brine systems. In contrast to aqueous systems, the diffusion coefficient of CO2 in hydrocarbons was found to be strongly dependent on pressure. At a given temperature the diffusion coefficient decreased by up to 50% over the pressure range investigated (1 to 69 MPa). A correlation based on the Stokes-Einstein equation and a two-parameter correlation based on the rough hard sphere theory was used to model the experimental results. The experimental uncertainty was found to be 1.5% with a coverage factor of 2.
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Kroupa, Zdeněk. "Posouzení metod CCS a CCU." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417864.
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The thesis focuses on CCS and CCU technologies, which could find application in industry and other sectors in the future. These technologies are used to reduce CO2 emissions, mainly from point sources. This thesis provides a comprehensive overview and division of CCS and CCU technologies and points out negative effects of its installation. Part of the work is also a comparison of individual steps of technology, both from an energetic and financial point of view. The aim is to show a wide range of influences on the final price and a significant discrepancy in the results of some scientific works. At the same time, in some parts, you can find a detailed description of individual parts of the technology.
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Ohannessian, Roupen. "Thermal Energy Storage Potential in Supermarkets." Thesis, KTH, Tillämpad termodynamik och kylteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-140647.
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The objective of this research is to evaluate the potential of thermal energy storage in supermarkets with CO2 refrigeration systems. Suitable energy storage techniques are investigated and the seasonal storage technology of boreholes is chosen to be the focus of the study. The calculations are done for five supermarket refrigeration systems with different combinations of heating systems and borehole thermal energy storage control strategies. The two heating systems analyzed are the ground source heat pump and the heat recovery from the supermarket’s refrigeration system. The simulation results show that the introduction of thermal energy storage in the scenarios with heat pump can reduce the annual total energy by 6.3%. It is also shown that increasing the number of boreholes can decrease the life cycle cost of the system. Moreover, it is established that a supermarket system with heat recovery consumes 8.1% less energy than the one using heat pump and adding thermal energy storage on the heat recovery system further improves the energy consumption by 3.7% but may become costly.
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Shu, Yutong. "Natural analogues for geological carbon storage." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31393.
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In CO2 storage sites, seal has a vital role in inhibiting migration of the supercritical CO2 to other geological strata. The major difficulties in studying seals include two aspects: lack of available samples (especially for saline aquifers), and the difficulty to study over geological time and spatial scales. The analysis of natural analogue has been chosen to overcome these difficulties. Hydrocarbon fields are used to investigate the pore throat radii, which is the major factor for capillary sealing of caprocks, using newly established statistics model. Natural CO2 springs at Green River, Utah are used to study how the long-term CO2 charge triggers chemical reactions and migration in shales. One of the major sealing mechanism of caprocks is capillary sealing. Pore throat radius, as the main factor to decide the capillary sealing, has been investigated in this study. As an alternative to the traditional method of mercury injection porosimetry, a statistical model for effective pore throat radii determination has been established. The cumulative percentage and the probability distribution of the effective pore throat radii of the shale caprocks in the UK North Sea oil fields are obtained, which would be used as a reference for the saline aquifers in CO2 storage siting in the future work. Monte Carlo simulation is utilised to get the distribution of the effective pore throat radii. The cumulative distribution from this study has been compared with the distribution by Yang and Aplin (1998). The distribution by the statistical model enables to narrow down the range of effective pore throat radii to 37nm~1700nm, and help to make a better prediction on the pore throat radii. The correlation between the controlling factors of faulting, burial depth, caprock thickness and the pore throat radii have been examined. Good correlation between the depth less than 3000m and the effective pore throat radii indicates clay diagenesis should be the major factor for shallowly buried caprocks. Faulting and caprock thickness present no significant correlation with the effective pore throat radii. Crystal Geyser is used as an ideal natural analogue to study the Mancos Shale alteration. The interacted fluid that deposited travertine is important for the study. Hence, carbonate veins and reduction zones that associated with the activity of the main fault are used as records of the geochemistry of the paleo-fluid, the features of which are compared to the present spring water. The result shows the paleo-fluid was much more saline than the present fluid, with greater flow-rate. The decreased flow-rate might be owing to the self-healing of the fault during the time. Mancos shales outcropped in the hanging wall of the Little Grand Wash fault were sampled to investigate on the alterations triggered by the CO2-charged fluid from the fault and fractures. The result shows the alteration radius of the Mancos has limited within the distance of 20m away from the fault. CO2-rich fluid could interact with deformed shale (both dissolution and precipitation might happen), but no evidence shows the intact Mancos has been altered. The calcite cements in Mancos derived from CO2 sequestration could reach up to 27% (%weight of the whole rock) at 15m away from the fault. The conclusion facilitates the carbon storage siting criteria by Chadwick et al., (2009), who proposed the cautionary thickness of the caprock to be 20m.
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Alcalde, Martín Juan. "3D seismic imaging and geological modeling of the Hontomin CO2 storage site, Spain." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/284824.
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This thesis is organized as a compendium of three scientific articles, describing the geological characterization of the Hontomín site for Geological Storage of CO2 by means of 3D seismic data, acquired for this purpose, as well as the available well-log and regional data. The three articles form the core of this thesis and constitute the main scientific effort developed therein. These are:
• Alcalde, J., Martí, D., Calahorrano, A., Marzán, I., Ayarza, P., Carbonell, R., Juhlin, C. and Pérez-Estaún, A. 2013a. Active seismic characterization experiments of the Hontomín research facility for geological storage of CO2, Spain. International Journal of Greenhouse Gas Control, 19, 785-795.
• Alcalde, J., Martí, D., Juhlin, C., Malehmir, A., Sopher, D., Saura, E., Marzán, I., Ayarza, P., Calahorrano, A., Pérez-Estaún, A., and Carbonell, R. 2013b. 3D Reflection Seismic Imaging of the Hontomín structure in the Basque-Cantabrian Basin (Spain). Solid Earth4, pp. 481-496.
• Alcalde, J., Marzán, I., Saura, E., Martí, D., Ayarza, P., Juhlin, C., Pérez-Estaún, A., and Carbonell, R. 2014. 3D geological characterization of the Hontomín CO2 storage site, Spain: multidisciplinary approach from seismics, well-logging and regional data. Tectonophysics (accepted).
The thesis begins with an Introduction (Chapter I), in which the motivations and aims of the thesis are presented. These include the problematic derived from anthropogenic emissions of CO2, and present Carbon Capture and Storage technology as an effective method to reach energetic sustainability. This chapter also includes the state-of-the-art seismic reflection method applied to CO2 storage, as well as an outline of the regional and local geology of the study area.
The first article (Alcalde et al., 2013a) constitutes Chapter II of the thesis. It presents and describes the active seismic experiments conducted at the Hontomín site for the seismic characterization. The data acquisition is described in detail, with an emphasis on the most relevant factors that affected the quality of the acquired data. These factors include the geomorphological/topographical aspects of the study area, logistical issues during the acquisition. The effects on the seismic records of a near-surface velocity inversion are also discussed. This contribution also shows a preliminary seismic image of the subsurface, which allows outlining the general dome shape of the target structure.
The second article (Alcalde et al., 2013b) comprises Chapter III of the thesis. It outlines the processing applied to the seismic data that led to the final migrated seismic image. It includes a detailed discussion about which processes were more effective in enhancing the quality of the obtained image. The image was judged to be suitable for interpretation and constitutes the primary seismic model, to be used as reference baseline during the monitoring stage. Furthermore, the top of the Jurassic dome structure was mapped, allowing us to provide an overall estimation of the size of the target structure, which is a 107 m2 elongated dome with a maximum CO2 storage capacity of 1.2 Gt.
The third article (Alcalde et al., 2014), included in Chapter IV of the thesis, focuses on the interpretation of the seismic image and the building of a 3D geological model. The quality of the seismic data required a geologically driven approach to enable interpretation. This approach used a conceptual model as reference, which was inferred in the first place from the correlation of the available well-log data and later improved by the seismic facies analysis and the regional geological data. The conceptual model was used to interpret the seismic data and resulted in a 9-layered 3D geological model and a thorough description of the fault system present in the area.<br>Esta tesis tiene como objetivo la caracterización geológica 3D de la Planta de Desarrollo Tecnológico para el Almacenamiento Geológico de CO2 de Hontomín (Burgos). Esta caracterización se ha llevado a cabo mediante el procesado y la interpretación de datos de sísmica de reflexión 3D adquiridos para ese propósito en verano de 2010.
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Mazzoldi, Alberto. "Leakage and atmospheric dispersion of CO2 associated with carbon capture and storage projects." Thesis, University of Nottingham, 2009. http://eprints.nottingham.ac.uk/11443/.
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Climate change is affecting planet Earth. The main cause is anthropogenic emissions of greenhouse gases, the principal one being carbon dioxide, released in the atmosphere as a by-product of the combustion of hydrocarbons for the generation of energy. Carbon capture and storage (CCS) is a technology that would prevent carbon dioxide from being emitted into the atmosphere by safely sequestering it underground. For so doing, CO2 must be captured at large emission points and transported at high pressure to underground reservoirs, where the gas can be injected and stored for thousands of years to come. During surface transportation, leakages from high pressure facilities would pose a risk to the general public, for carbon dioxide is toxic at high concentrations. In this study, atmospheric dispersion of carbon dioxide is studied by the usage of software that solves mathematical equations and algorithms simulating the pollutant dispersion. Dispersion models are used to estimate or predict downwind distances covered by toxic concentrations of the pollutant, emitted from sources such as high-pressure transportation facilities within CCS projects. Two modelling tools from two different classes (Gaussian ALOHA 5.4 and Computational Fluid Dynamics PANACHE 3.4.1) have been evaluated against release field experiments using the statistical model evaluation method proposed by Hanna et al. (1993,2004) and Hanna and Chang (2001), and applied for the consideration of the dense gas CO2, released in large amounts due to leakages. Predictions from the two models have been compared and the limitations of both examined, when dealing with a gas that presents the distinctive physical characteristics of carbon dioxide. The models have been used and compared in simulating representative failure cases within CCS transportation with release parameters taken from the literature. The Computational Fluid Dynamics (CFD) model showed a much higher precision when describing the release of the gas from a HP facility, mainly when dealing with the jet release caused by leakages of any dimensions. When dealing with the transportation of toxic gases, the magnitude of hazards posed by potential failure events within the transportation system is proportional to the extent of the area covered by toxic concentrations of the gas, when modelling representative leakages. Results of this investigation depict a lowering of the Risk involved in the transportation of CO2 by up to an order of magnitude, when modelling the same releases with CFD tools, instead of the more common Gaussian models. The European Union recognizes that deployment of CCS for hydrocarbon power generation, in parallel with the production of renewable energies, is the only way to meet the target for temperature stabilization. For its Impact Assessment on CCS, the EU used results from a risk assessment compiled after the utilization of a Gaussian model. In this thesis, a criticism of this choice is put forward, considering that, when introducing the technology to the general public and regional scale administrators, a Risk Assessment derived using results from Gaussian models can over-estimate the risk in a way not favourable to the purpose.
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Popova, Olga. "Development of Geostatistical Models to Estimate CO2 Storage Resource in Sedimentary Geologic Formations." Research Showcase @ CMU, 2014. http://repository.cmu.edu/dissertations/485.
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Carbon capture and sequestration (CCS) is a technology that provides a near-term solution to reduce anthropogenic CO2 emissions to the atmosphere and reduce our impact on the climate system. Assessments of carbon sequestration resources that have been made for North America using existing methodologies likely underestimate uncertainty and variability in the reservoir parameters. This thesis describes a geostatistical model developed to estimate the CO2 storage resource in sedimentary formations. The proposed stochastic model accounts for the spatial distribution of reservoir properties and is implemented to a case study of the Oriskany Formation of the Appalachian sedimentary basin. The developed model allows for estimation of the CO2 sequestration resource of a storage formation with subsequent uncertainty analysis. Since the model is flexible with respect to changing input parameters and assumptions it can be parameterized to calculate the CO2 storage resource of any porous subsurface unit. The thesis continues with evaluation of the cost of CO2 injection and storage for the Oriskany Formation utilizing storage resource estimates generated by our geostatistical model. Our results indicate that the cost of sequestering CO2 has significant spatial variation due to heterogeneity of formation properties and site geology. We identify the low-cost areas within the Oriskany footprint. In general, these areas correspond to the deepest portions of the Appalachian basin and could be considered as potential CO2 injection sites for CCS industrial scale projects. Overall, we conclude that significant improvement can be made by integrating basin geology and spatial heterogeneity of formation petrophysical properties into CCS cost assessments, and that should be a focus of future research efforts. This will allow for more accurate cost estimates for the entire CCS system and identify areas of sedimentary basins with optimal conditions for CO2 injection and storage. To mitigate the effects of climate change, the U.S. will need a widespread deployment of low-carbon electricity generating technologies including natural gas and coal with CCS. More precise CO2 storage resource and CCS cost estimates will provide better recommendations for government and industry leaders and inform their decisions on what greenhouse gas mitigation measures are the best fit for their regions.
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RODRIGUES, ROBERTA DOMINGOS. "NUMERICAL MODELING OF CO2 INJECTION IN SALINE AQUIFERS, AIMING TO EVALUATE MINERAL STORAGE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2017. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=32317@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO<br>COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR<br>PROGRAMA DE EXCELENCIA ACADEMICA<br>Para contribuir com a mitigação das mudanças climáticas, tecnologias com o intuito de promover a redução de emissões dos Gases de Efeito Estufa, como é o caso do dióxido de carbono, tem obtido grande destaque nas pesquisas ultimamente. Uma das alternativas para impedir que todo esse carbono seja liberado para a
atmosfera é reinjetar o CO2 nos próprios reservatórios ou em outras formações geológicas próximas. Neste sentido, esta dissertação apresenta uma tecnologia relacionada à captura e armazenamento geológico de CO2 e avalia o processo de injeção de dióxido de carbono em aquíferos salinos. O principal objetivo é avaliar o processo de injeção de dióxido de carbono em aquíferos salinos de rochas carbonáticas, numa escala de tempo de três mil anos, para avaliar o aprisionamento do CO2 em suas diferentes formas, incluindo o armazenamento mineral. Tal estudo também considera na modelagem, as reações químicas entre os componentes na fase aquosa e a difusão molecular do dióxido de carbono na fase aquosa, assim como as reações químicas de dissolução e precipitação mineral. A partir das informações obtidas em literatura, estabeleceu-se as premissas para a simulação do caso base, e gerou-se casos derivados variando individualmente cada uma das seguintes propriedades: difusividade, salinidade, pH e temperatura, no qual avaliou-se a contribuição de cada uma delas nas diferentes formas de armazenamento do CO2. Por fim, concluiu-se que a mineralização do CO2 iniciou-se após aproximadamente 200 anos de simulação. No entanto, devido às lentas taxas da reação de precipitação mineral, a predominância do armazenamento do CO2 ainda foi na forma dissolvida. As propriedades variadas que contribuíram para o aumento do armazenamento mineral de CO2, que é considerada a forma mais estável, foram: menor fator de difusividade, maior salinidade do aquífero, pH básico (pH igual a 8,0) e
maior temperatura.<br>In order to contribute to climatic changes mitigation, technologies aiming the reduction of pollution gases emissions, such as carbon dioxide, have been highlighted in recent researches. One of the alternatives to prevent all this carbon from being released into the atmosphere is to reinject CO2 into reservoirs or in other nearby geological formations. In this sense, this work presents a technology related to the capture and geological storage of CO2 and evaluates the carbon dioxide injection process into saline aquifers. The main objective is to evaluate the carbon dioxide injection process in saline aquifers of carbonate rocks, in a time scale of three thousand years, to evaluate the storage mechanism of CO2 in its different
forms, including mineral storage. Such study also considers in the modeling, the chemical reactions between the components in the aqueous phase and the molecular diffusion of the carbon dioxide in the aqueous phase, as well as the chemical reactions of mineral dissolution and precipitation. From the research made and the information gathered in the literature, the premises for the simulation of the base case were established, and derivative cases were generated by individually varying each of the following properties: diffusivity, salinity, pH and temperature, in which the contribution of each property was evaluated on the different CO2 storage forms. Finally, it was concluded that the injected CO2 mineralization process started after approximately 200 years of simulation. However, due to slow rates of the mineral precipitation, the CO2 storage in the dissolved form was still predominant. The different properties that contributed to increase the CO2 mineral storage, which is considered the more estable one, were: lower diffusivity factor, higher aquifer salinity, basic pH (pH equal to 8.0) and higher temperature.
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Tian, Liang. "CO2 storage in deep saline aquifers : Models for geological heterogeneity and large domains." Doctoral thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-279382.
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This work presents model development and model analyses of CO2 storage in deep saline aquifers. The goal has been two-fold, firstly to develop models and address the system behaviour under geological heterogeneity, second to tackle the issues related to problem scale as modelling of the CO2 storage systems can become prohibitively complex when large systems are considered. The work starts from a Monte Carlo analysis of heterogeneous 2D domains with a focus on the sensitivity of two CO2 storage performance measurements, namely, the injectivity index (Iinj) and storage efficiency coefficient (E), on parameters characterizing heterogeneity. It is found that E and Iinj are determined by two different parameter groups which both include correlation length (λ) and standard deviation (σ) of the permeability. Next, the issue of upscaling is addressed by modelling a heterogeneous system with multi-modal heterogeneity and an upscaling scheme of the constitutive relationships is proposed to enable the numerical simulation to be done using a coarser geological mesh built for a larger domain. Finally, in order to better address stochastically heterogeneous systems, a new method for model simulations and uncertainty analysis based on a Gaussian processes emulator is introduced. Instead of conventional point estimates this Bayesian approach can efficiently approximate cumulative distribution functions for the selected outputs which are CO2 breakthrough time and its total mass. After focusing on reservoir behaviour in small domains and modelling the heterogeneity effects in them, the work moves to predictive modelling of large scale CO2 storage systems. To maximize the confidence in the model predictions, a set of different modelling approaches of varying complexity is employed, including a semi-analytical model, a sharp-interface vertical equilibrium (VE) model and a TOUGH2MP / ECO2N model. Based on this approach, the CO2 storage potential of two large scale sites is modelled, namely the South Scania site, Sweden and the Dalders Monocline in the Baltic Sea basin. The methodologies developed and demonstrated in this work enable improved analyses of CO2 geological storage at both small and large scales, including better approaches to address medium heterogeneity. Finally, recommendations for future work are also discussed.
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Sánchez, Yamid Alberto Carranza. "Exergy and environmental assessment of FPSO offshore platforms with CO2 capture and storage." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3150/tde-26062017-140458/.
Full textAbstract:
Offshore oil platforms are used for the exploitation and production of hydrocarbons and consist of a processing plant and a utility plant. The oil and gas industry operations are energy-intensive and, in the case of offshore platforms, the need to decrease energy consumption and reduce CO2 emissions has increased. In the oil and gas industry, the ISO 50001 standard promotes the implementation of energy management systems and proposes indicators based on energy. Interestingly, after several decades of knowledge of the concept of exergy, this has not been formally implemented in the programs and strategies of the oil and gas industry organizations. In this research, the implementation of the exergy method and the carbon capture and storage strategy for the assessment of the performance of a floating, production and storage offloading units FPSO is proposed. FPSO platforms and their processing and utility plants may have different configurations depending on, among others, the reservoir characteristics and production requirements. The possible configurations can therefore be numerous. In this sense, some operation scenarios based on different well-fluid compositions and operation modes are studied. The platform models are developed and simulated using the software Aspen HYSYS®. Results show that, on average, the reduction of 88.8% in CO2 emissions is penalized with a reduction in exergy efficiency of 1.7 points. Further, results allow a better understanding of exergy and environmental performance of the FPSO.<br>Plataformas de petróleo offshore são utilizadas para a exploração e produção de hidrocarbonetos e consistem em uma planta de processamento e uma planta de utilidade. As operações da indústria de petróleo e gás são de energia intensiva e, no caso de plataformas offshore, é necessário cada vez mais diminuir o consumo de energia e reduzir as emissões de CO2. Na indústria de petróleo e gás, a norma ISO 50001 promove a implementação de sistemas de gestão de energia e propõe indicadores baseados em energia. Entretanto, após várias décadas de conhecimento do conceito de exergia, este não foi formalmente implementado nos programas e estratégias das organizações da indústria de petróleo e gás. Neste trabalho, propõe-se a implementação da análise exergética e a estratégia de captura e armazenamento de carbono para a avaliação do desempenho de unidades flutuantes, de produção, de armazenamento e transferência FPSO. As plataformas FPSO e suas plantas de processamento e utilidade podem ter diferentes configurações dependendo, entre outras, das características do reservatório e dos requisitos de produção. As configurações possíveis podem, portanto, ser numerosas. Neste sentido, são estudados alguns cenários de operação baseados em diferentes composições dos fluidos do poço e em três modos de operação. Os modelos de plataforma são desenvolvidos e simulados usando o software Aspen HYSYS®. Os resultados mostram que, em média, a redução de 88,8% nas emissões de CO2 é penalizada com uma redução da eficiência exergética de 1,7 pontos. Além disso, os resultados permitem uma melhor compreensão da exergia e desempenho ambiental do FPSO.
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Kilgallon, Rachel. "Investigating the role of chemical and geochemical tracers for CO2 transport and storage." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/21702.
Full textAbstract:
Changes in the atmospheric concentration of greenhouse gases and aerosols alter the energy balance of the climate system. CO2 is the most significant anthropogenic greenhouse gas. The primary source of the increased atmospheric concentration of CO2 since the preindustrial period is from fossil fuel exploitation. As the global need for energy is currently met by combustion of fossil fuels it is imperative that a method of reducing the levels of CO2 being emitted is used. Carbon capture and storage (CCS) is the combination of CO2 capture from large point sources, with the transport of CO2 to a suitable geological storage site where it can safely be contained. Geological CCS technology has the potential to a make a significant contribution to a low carbon technology future. As with any technology, it is imperative to identify techniques that could be used to form part of the monitoring programme. In this thesis, the role of chemical and geochemical tracers are investigated during the transport and storage of CO2. For the first part of this research, a review of the natural gas and CO2 pipeline network in North America and United Kingdom has been compiled from published literature and historical experience. Using this information, research was carried out to determine why odourising has been suggested for CO2 pipeline transport and what benefit it would add. Based on experience from natural gas, it is concluded that high pressure pipelines of CO2 through sparsely populated areas could have odourant added, but will gain little safety benefit. However, adding odourant to CO2 gas phase pipes could aid detection of leaks as well improve public assurance and should be considered in more detail. For the second part of this research, a specially constructed flow cell was designed and built to investigate how noble gases could be used as effective early warning tracers for CO2 migration in storage sites. From this equipment, experimental breakthrough curves for noble gases and SF6 travelling through a sample of Fell sandstone in relation to CO2 over a pressure gradient range of 10,000 – 50,000 Pa were generated. Although noble gases are described as conservative tracers, comparing the breakthrough curves over a range of pressure gradients show that they do not behave as simply as previously assumed. These results were then modelled using a one dimensional advective dispersion transport equation to fit curves to the experimental outputs using two different modelling approaches. A statistical approach can derive the input parameters for an analytical approach, which is needed to understand the dispersivity behaviour of the tracers. A set of values for the dispersivity of noble gases, SF6 and CO2 through porous media is presented in this research. Using a baseline value approach, initial arrival times for krypton and xenon from this research suggest that they could be used as a means of detecting CO2 migration. While helium, neon and argon appear to be unsuitable as early warning tracers for initial detection of CO2, this suggests that they can be used as part of mixture to fingerprint individual CO2 storage sites that may be in close proximity to one another. Results from the experimental and modelling analysis, identify a system where preferential paths exist depending on the change in pressure gradient. The different transport channels progress from a Darcy linear flow regime to a non-linear laminar flow. These results propose an explanation for the patterns observed from tracers in large-scale reservoirs but the output values obtained are limited by scale-dependence and would not be suitable for direct upscaling.
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Okhulkova, Tatiana. "Integration of uncertainty and definition of critical thresholds for CO2 storage risk assessment." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLC021/document.
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L'objectif principal de la thèse est de définir comment l'incertitude peut être prise en compte dans leprocessus d'évaluation des risques pour le stockage de CO2 et de quantifier, à l'aide de modèles numériques,les scénarios de fuite par migration latérale et à travers la couverture. Les scénarios choisis sont quantifiéspar l'approche de modélisation de système pour laquelle des modèles numériques prédictifs ad-hoc sontdéveloppés. Une étude probabiliste de propagation d'incertitude paramétrique par un méta-modèle depolynômes de chaos est réalisée. La problématique de la prise en compte de la variabilité spatiale comme unesource d'incertitude est éclairée et une étude comparative entre représentations homogène et hétérogène de laperméabilité est fournie<br>The main goal of the thesis is to define how the uncertainty can be accounted for in the process of riskassessment for CO2 storage and to quantify by means of numerical models the scenarii of leakage by lateralmigration and through the caprock. The chosen scenarii are quantified using the system modeling approachfor which ad-hoc predictive numerical models are developed. A probabilistic parametric uncertaintypropagation study using polynomial chaos expansion is performed. Matters of spatial variability are alsodiscussed and a comparison between homogeneous and heterogeneous representations of permeability isprovided
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Rasmusson, Kristina. "Modeling of geohydrological processes in geological CO2 storage – with focus on residual trapping." Doctoral thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-327994.
Full textAbstract:
Geological storage of carbon dioxide (CO2) in deep saline aquifers is one approach to mitigate release from large point sources to the atmosphere. Understanding of in-situ processes providing trapping is important to the development of realistic models and the planning of future storage projects. This thesis covers both field- and pore-scale numerical modeling studies of such geohydrological processes, with focus on residual trapping. The setting is a CO2-injection experiment at the Heletz test site, conducted within the frame of the EU FP7 MUSTANG and TRUST projects. The objectives of the thesis are to develop and analyze alternative experimental characterization test sequences for determining in-situ residual CO2 saturation (Sgr), as well as to analyze the impact of the injection strategy on trapping, the effect of model assumptions (coupled wellbore-reservoir flow, geological heterogeneity, trapping model) on the predicted trapping, and to develop a pore-network model (PNM) for simulating and analyzing pore-scale mechanisms. The results include a comparison of alternative characterization test sequences for estimating Sgr. The estimates were retrieved through parameter estimation. The effect on the estimate of including various data sets was determined. A new method, using withdrawal and an indicator-tracer, for obtaining a residual zone in-situ was also introduced. Simulations were made of the CO2 partitioning between layers in a multi-layered formation, and parameters influencing this were identified. The results showed the importance of accounting for coupled wellbore-reservoir flow in simulations of such scenarios. Simulations also showed that adding chase-fluid stages after a conventional CO2 injection enhances the (residual and dissolution) trapping. Including geological heterogeneity generally decreased the estimated trapping. The choice of trapping model may largely effect the quantity of the predicted residual trapping (although most of them produced similar results). The use of an appropriate trapping model and description of geological heterogeneity for a site when simulating CO2 sequestration is vital, as different assumptions may give significant discrepancies in predicted trapping. The result also includes a PNM code, for multiphase quasi-static flow and trapping in porous materials. It was used to investigate trapping and obtain an estimated trapping (IR) curve for Heletz sandstone.
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Mateu, Royo Carlos. "Field Measurements and Modelling Analysis of CO2 Refrigeration Systems with Integrated Geothermal Storage." Thesis, KTH, Energiteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-212549.
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The aim of this study is to investigate the potential of CO2 trans-critical booster refrigeration system integrated with geothermal storage to provide the cooling and the heating demands with high energy efficiency. During summer season, heat is rejected from the CO2 refrigeration system, increasing the amount of sub-cooling and storing this heat into the ground. During winter season, the heat stored in the ground is extracted and used as heat source to provide the heating requirements of the supermarket. Using field measurements data from medium size supermarkets in Sweden, existing solutions for integrated geothermal storage in a CO2 refrigeration system as well as proposal solution are modelled and compared with stand-alone CO2 trans-critical booster system. The techno-economical comparative analysis shows that hybrid CO2 trans-critical booster system with GSHP as an integrated geothermal solution has 6% lower annual energy use than a stand-alone CO2 system with heat recovery solution for refrigeration and heating in North of Europe. In addition to the computer simulations, field measurements monitoring of ten medium size supermarkets with integrated geothermal storage have been studied. Measurement system proposal guide is done to fulfill a proper energy analysis of the supermarket installation with the integrated solution. Evaluation of the missing measurements is done for the available supermarkets. One important conclusion of this part is that none of the supermarkets analyzed has enough measurement to realize a proper and comprehensive energy analysis.<br><p>ISBN: 978-91-7729-513-6</p>
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Gomes, Ana Sofia Ferrada. "Matching CO2 large point sources and potential geological storage sites in mainland Portugal." Master's thesis, FCT - UNL, 2008. http://hdl.handle.net/10362/1884.
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Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Engenharia do Ambiente, Perfil Gestão e Sistemas Ambientais<br>Fossil fuel combustion is the major source of the increasing atmospheric concentration
of carbone dioxide (CO2) since the pre-industrial period. Combustion systems like power plants, cement, iron and steel production plants and refineries are the main
stationary sources of CO2 emissions. The reduction of greenhouse gas emissions in one
of the main climate change mitigation measures. Carbon dioxide capture and storage
(CCS) is one of the possible mitigation measures.
The objective of this study was to analyze the hypothesis for the implementation of
CCS systems in mainland Portugal based on source-sink matching. The CO2 large point
sources (LPS) considered in mainland Portugal were the largest installations included in the Phase II of the European Emissions Trading Scheme with the highest CO2
emissions, representing about 90% of the total CO2 emissions of the Trading Scheme,
verified in 2007. The potential geological storage locations considered were the
geological formations formerly identified in existing studies.
After the mapping of LPS and potential geological sinks of mainland Portugal, an
analysis based on the proximity of the sources and storage sites was performed. From
this it was possible to conclude that a large number of LPS are within or near the
potential storage areas. An attempt of estimating costs of implementing a CCS system
in mainland Portugal was also performed, considering the identified LPS and storage
areas. This cost estimate was a very rough exercise but can allow an order of magnitude
of the costs of implementing a CCS system in mainland Portugal. Preliminary results
suggest that at present CCS systems are not economically interesting in Portugal, but
this may change with increasing costs of energy and emission permits.
The present lack of information regarding geological storage sites is an important
limitation for the assessment of implementing a CCS system in mainland Portugal.
Further detailed studies are required, starting with the characterisation of geological sites and the candidate sources to CCS, from technical aspects to environmental and economical factors.
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Occhineri, Lorenzo. "Technical and economic assessments of CO2 capture processes in power plants." Thesis, Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-4705.
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Ors, Oytun. "Investigation Of The Interaction Of Co2 And Ch4 Hydrate For The Determination Of Feasibility Of Co2 Storage In The Black Sea Sediments." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614673/index.pdf.
Full textAbstract:
Recently, carbon dioxide injection into deep sea sediments has become one of the carbon dioxide mitigation methods since carbon dioxide hydrates are stable at the prevailing pressure and temperature conditions.
The Black Sea, which is one of the major identified natural methane hydrate regions of the world, can be a good candidate for carbon dioxide storage in hydrate form. Injected carbon dioxide under the methane hydrate stability region will be in contact with methane hydrate which should be analyzed thoroughly in order to increase our understanding on the gaseous carbon dioxide and methane hydrate interaction.
For the storage of huge amounts of CO2, geological structure must contain an impermeable barrier. In general such a barrier may consist of clay or salt. In this study, sealing efficiency of methane hydrate and long term fate of the CO2 disposal under the methane hydrate zone is investigated.
In order to determine the interaction of CO2 and CH4 hydrate and the sealing efficiency of CH4 hydrate, experimental setup is prepared and various tests are performed including the CH4 hydrate formation in both bulk conditions and within sand particles, measurement of the permeability of unconsolidated sand particles that includes 30% and 50% methane hydrate saturations and injection of CO2 into the CH4 hydrate.
Results of the experiments indicate that, presence of hydrate sharply decreases the permeability of the unconsolidated sand system and systems with hydrate saturations greater than 50% may act as an impermeable layer. Also, CO2-CH4 swap within the hydrate cages is observed at different experimental conditions. As a result of this study, it can be concluded that methane hydrate stability region in deep sea sediments would be a good alternative for the safe storage of CO2. Therefore, methane hydrate stability region in the Black Sea sediments can be considered for the disposal of CO2.
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Kampman, Niko. "Fluid-rock interactions in a carbon storage site analogue, Green River, Utah." Thesis, University of Cambridge, 2011. https://www.repository.cam.ac.uk/handle/1810/244506.
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Reactions between CO2-charged brines and reservoir minerals might either enhance the long-term storage of CO2 in geological reservoirs or facilitate leakage by corroding cap rocks and fault seals. Modelling the progress of such reactions is frustrated by uncertainties in the absolute mineral surface reaction rates and the significance of other rate limiting steps in natural systems. This study uses the chemical evolution of groundwater from the Jurassic Navajo Sandstone, part of a leaking natural accumulation of CO2 at Green River, Utah, in the Colorado Plateau, USA, to place constraints on the rates and potential controlling mechanisms of the mineral-fluid reactions,under elevated CO2 pressures, in a natural system. The progress of individual reactions, inferred from changes in groundwater chemistry is modelled using mass balance techniques. The mineral reactions are close to stoichiometric with plagioclase and K-feldspar dissolution largely balanced by precipitation of clay minerals and carbonate. Mineral modes, in conjunction with published surface area measurements and flow rates estimated from hydraulic head measurements, are then used to quantify the kinetics of feldspar dissolution. Maximum estimated dissolution rates for plagioclase and K-feldspar are 2x10-14 and 4x10-16 mol·m-2·s-1, respectively. Fluid ion-activity products are close to equilibrium (e.g. DGr for plagioclase between -2 and -10 kJ/mol) and lie in the region in which mineral surface reaction rates show a strong dependence on DGr. Local variation in DGr is attributed to the injection and disassociation of CO2 which initially depresses silicate mineral saturation in the fluid, promoting feldspar dissolution. With progressive flow through the aquifer, feldspar hydrolysis reactions consume H+ and liberate solutes to solution which increase mineral saturation in the fluid and rates slow as a consequence. The measured plagioclase dissolution rates at low DGr would be compatible with far-from-quilibrium rates of ~1x10-13 mol·m-2·s-1 as observed in some experimental studies. This suggests that the discrepancy between field and laboratory reaction rates may in part be explained by the differences in the thermodynamic state of natural and experimental fluids, with field-scale reactions occurring close to equilibrium whereas most laboratory experiments are run far-from-equilibrium. Surface carbonate deposits and cementation within the footwall of the local fault systems record multiple injections of CO2 into the Navajo Aquifer and leakage of CO2 from the site over ca. 400,000 years. The d18O, d13C and 87Sr/86Sr of these deposits record rapid rates of CO2 leakage (up to ~1000 tonnes/a) following injection of CO2, but rates differ by an order of magnitude between each fault, due to differences in the fault architecture. Elevated pCO2 enhances rates of feldspar dissolution in the host aquifer and carbonate precipitation in fracture conduits. Silicate mineral dissolution rates decline and carbonate precipitation rates increase as pH and the CO2 charge dissipate. The Sr/Ca of calcite cements record average precipitation rates of ~2x10-6 mol/m2/s, comparable to laboratory derived calcite precipitation rates in fluids with elevated Mn/Ca and Fe/Ca, at cc of ~1 to 3. This suggests that far-from-equilibrium carbonate precipitation, which blocks fracture conduits and causes the leaking system to self-seal, driven by CO2 degassing in the shallow subsurface, can be accurately modeled with laboratory derived rates. Sandstones altered in CO2 leakage conduits exhibit extensive dissolution of hematite grain coatings and are chemically bleached as a result. Measurements of Eh-pH conditions in the modern fluid, and modeling of paleo-Eh-pH conditions using calcite Fe and Mn concentrations, suggests that the CO2-charged groundwaters are reducing, due to their low dissolved O2 content and that pH suppression due to high pCO2 is capable of dissolving and transporting large concentrations of metals. Exhumed paleo-CO2 reservoirs along the crest of the Green River anticline have been identified using volatile hosting fluid inclusions. Paleo-CO2-charged fluids mobilized hydrocarbons and CH4 from deeper formations, enhancing the reductive dissolution of hematite, which produced spectacular km-scale bleached patterns in these sediment.
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Moss, Jared B. "Computational and Experimental Studies on Energy Storage Materials and Electrocatalysts." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7537.
Full textAbstract:
With the growing global population comes the ever-increasing consumption of energy in powering cities, electric vehicles, and portable devices such as cell-phones. While the power grid is used to distribute energy to consumers, the energy sources needed to power the grid itself are unsustainable and inefficient. The primary energy sources powering the grid, being fossil fuels, natural gas, and nuclear, are unsustainable as the economically-accessible reserves are continually depleted in exchange for detrimental emissions and air-pollutants. Cleaner, renewable sources, such as solar, wind, and hydroelectric, are intermittent and unreliable during the peak hours of energy usage, that is dawn and dusk. However, during waking hours and nighttime sleeping hours, energy consumption plummets resulting in substantial losses of potential energy as these intermittent energy providers do not have the infrastructure to store unused energy. Therefore, the research and development of efficient energy storage materials and renewable energy sources is critical to meet the needs of society in their fundamental operation while reducing harmful emissions. The research presented in this thesis focuses on selected energy storage materials and electrocatalysts as attractive technology for sustainable and benign renewable energy chemistry. Specifically, (1) theoretical studies on magnesium chloride / aluminum chloride electrolytes provide insight for further development of Mg batteries; (2) theoretical and experimental studies on viologen derivatives for organic redox flow batteries advance the development of these two-electron storage systems; and (3) a new iron(II) polypyridine catalyst that was found to electrochemically reduce CO2 to produce renewable fuels such as carbon monoxide (CO), hydrogen (H2), and methane (CH4), as well as promote the photochemical CO2-to-methane conversion with visible light.
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Lind, Mårten. "Opportunities and uncertainties in the early stages of development of CO2 capture and storage." Doctoral thesis, KTH, Energiprocesser, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10985.
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The topic of this thesis is carbon dioxide (CO2) capture and storage (CCS), which is a technology that is currently being promoted by industries, scientists and governments, among others, in order to mitigate climate change despite a continued use of fossil fuels. Because of the complex nature of CCS and the risks it entails, it is controversial. The aim of this thesis is to analyse how the technology may be further developed in a responsible manner. In the first part of the thesis different methods for capturing CO2 from industrial processes as well as power plants are analysed. The aim is to identify early opportunities for CO2 capture, which is considered important because of the urgency of the climate change problem. Three potential early opportunities are studied: i) capturing CO2 from calcining processes such as cement industries by using the oxyfuel process, ii) capturing CO2 from pressurised flue gas, and iii) capturing CO2 from hybrid combined cycles. Each opportunity has properties that may make them competitive in comparison to the more common alternatives if CCS is realised. However, there are also drawbacks. For example, while capturing CO2 from pressurised flue gas enables the use of more compact capture plant designs as well as less expensive and less toxic absorbents, the concept is neither suitable for retrofitting nor has it been promoted by the large and influential corporations. The second part of the thesis has a broader scope than the first and is multidisciplinary in its nature with inspiration from the research field of Science and Technology Studies (STS). The approach is to critically analyse stakeholder percep-tions regarding CCS, with a specific focus on the CCS experts. The thesis sheds new light on the complexity and scientific uncertainty of CCS as well as on the optimism among many of its proponents. Because of the uncertain development when it comes to climate change, fossil fuel use and greenhouse gas emissions, the conclusion is that CCS has to be further developed and demonstrated. A responsible strategy for a future development of CCS would benefit from: i) a search for win-win strategies, ii) increasing use of appropriate analytical tools such as life-cycle analysis, iii) a consideration of fossil fuel scarcity and increasing price volatility, iv) funding of unbiased research and v) increasing simultaneous investments in long-term solutions such as renewable energy alternatives and efficiency improvements.<br>QC 20100727
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Vilamajó, Llobera Eloi 1988. "CSEM monitoring at the Hontomín CO2 storage site: modeling, experimental design and baseline results." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/400761.
Full textAbstract:
This thesis is devoted to the development of a land-based controlled-source electromagnetics (CSEM) experimental methodology to be applied to the monitoring of CO2 storage at the Technological Development Plant (TDP) of Hontomín (Burgos, Spain). The main objectives of the thesis are 1) the evaluation of the feasibility of performing a CSEM monitoring at Hontomín, 2) the design of the CSEM monitoring experiment, and 3) the acquisition of the baseline (pre-injection) data set and the processing of the data obtaining the geoelectrical response of the structure.
A modeling experiment has been performed simulating the resistivity changes in the reservoir caused by the storage and evaluating the ability of the method to detect them. The study analyzes the capabilities of different experimental configurations (source/receiver location and relative orientation, emission frequencies...) in order to decide the appropriate configuration in views of the real experiment.
The study considered the simulation of an experimental configuration in two different moments of the storage process (pre- and post-injection). It compares the synthetic results obtained in each case and seeks the differences to infer the presence of CO2. A wide range of scenarios of increasing complexity were simulated, from 1D models with an infinite CO2 plume to models with a 3D plume in a medium that contains the casings of the injection and monitoring wells and considers the noise conditions at the Hontomín TDP. The CO2 effect on the synthetic data was analyzed with two different approaches: quantifying the signal caused by the CO2 on the data, TLS (time-lapse signal), and comparing it with the noise conditions in the study area, D (detectability). A borehole-to-surface configuration is sensitive to the presence of CO2, to its saturation and to the relative position source/plume. Furthermore, it was observed that the steel casings installed in the injection and monitoring wells affect the EM propagation from the transmitter to the surface. The study concluded that the CSEM monitoring is suitable at Hontomín given that measurable changes will occur between time- lapsed data sets.
Considering the results obtained in the modeling study, the CSEM monitoring experiment was designed. The baseline acquisition was carried out between April 21st and 26th 2014. A borehole-to-surface configuration was used with three different transmitter dipoles: 1) vertical dipole in the injection well HI (dVED-1), 2) vertical dipole in the monitoring well HA dVED- 2), and 3) horizontal dipole using one electrode in each well (dHED). Receivers were distributed at the surface in two different patterns: cross-shape and circular-shape. During each emission, 86 surface dipoles were measuring the electric field.
Data processing focused on the obtaining of the geoelectrical response of the subsurface for each source/receiver configuration and for each processed frequency. To this goal, time
series were divided into segments and, for each one, the transfer function between source transmission and receiver electric field were calculated. Experimental data were analyzed in terms of experimental uncertainty (error associated to each measurement) and experimental repeatability.
Experimental results allowed to characterize the geoelectrical response of the Hontomín structure (including steel casings). Baseline data quality is high: experimental errors are lower than 1% in amplitude and 1º in phase for most of the data points. Repeatability is high (differences lower than 1% in most of the cases).
The casing influence over the experimental data was investigated. We tested the hypothesis that a current was induced along the casing of the injection well. To reproduce the experimental behavior of the data, a number of scenarios have been simulated. For low frequencies, the hypothesis can explain the experimental data.
Considering the high data quality obtained and the results of the modeling study, we consider that the CSEM experiment will be able to detect the CO2-caused resistivity changes in the reservoir after the post-injection repetition of the experiment.<br>Aquesta tesi se centra en el desenvolupament del mètode electromagnètic de font controlada (CSEM) aplicat al monitoratge de l’emmagatzematge geològic de diòxid de carboni (CO2) a la Planta de Demostració Tecnològica (PDT) d’Hontomín (Burgos). El control del comportament del CO2 es basa en la detecció dels canvis de resistivitat que tenen lloc al reservori un cop el CO2 desplaça la salmorra. La tesi engloba el progrés de l’experiment de monitoratge CSEM des dels seus inicis fins a l’actualitat.
En primer lloc, s’avalua la viabilitat del monitoratge mitjançant el mètode CSEM a partir d’un estudi de modelització numèrica i s’analitzen les bondats de diferents configuracions experimentals. L’estudi consisteix en la simulació d’una configuració experimental en dos estadis del procés d’emmagatzematge (pre-injecció i post-injecció) i en la comparació dels resultats sintètics amb l’objectiu de relacionar les diferències amb la presència del CO2. Inclou la simulació d’un ampli rang d’escenaris de complexitat creixent. Es proposen dues aproximacions diferents per poder quantificar el senyal causat pel CO2 i comparar-lo amb les condicions de soroll reals a Hontomín.
En segon lloc, es descriu el disseny del dispositiu de control de l’evolució temporal de la ploma de CO2 aplicat a la PDT d’Hontomín i la realització de la campanya pre-injecció. El processat de les dades experimentals ha consistit en el càlcul de la resposta geoelèctrica de la formació geològica, incloent les carcasses metàl·liques dels pous d’injecció i monitoratge. Les dades experimentals s’analitzen en funció del seu error experimental i de la seva repetibilitat. La qualitat de les dades experimentals pre-injecció és alta respecte als dos punts de vista: els errors experimentals són inferiors a l’1% en l’amplitud i a 1º en la fase per la majoria de les dades i les diferències en la repetibilitat són inferiors a l’1% en la majoria dels casos.
Finalment, s’estudia la influència de les carcasses sobre les dades experimentals. S’investiga si la inducció d’un corrent al llarg de la carcassa del pou d’injecció pot explicar el seu comportament. A partir de la simulació de diferents escenaris, s’ha comprovat que la hipòtesi és capaç de reproduir el comportament qualitatiu de les dades a freqüències baixes.