Change search
ReferencesLink to record
Permanent link

Direct link
CO2 storage in deep saline aquifers: Models for geological heterogeneity and large domains
Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.ORCID iD: 0000-0002-9417-5586
2016 (English)Doctoral thesis, comprehensive summary (Other academic)Alternative title
二氧化碳的深部盐水层地质封存 : 储层非均质性及大尺度模型的研究 (Chinese)
Abstract [en]

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.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2016. , 70 p.
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 1390
Keyword [en]
CO2, Carbon Capture Storage, Storage Capacity, Injectivity, Monte Carlo, Gaussian, Permeability, Upscaling
Keyword [zh]
二氧化碳, 地質封存, 高斯仿真, 滲透係數, 非均質性, 升尺度, 存儲效能, 場地模擬, 不確定性, 壓力累積
National Category
Geosciences, Multidisciplinary
Identifiers
URN: urn:nbn:se:uu:diva-279382ISBN: 978-91-554-9625-8OAI: oai:DiVA.org:uu-279382DiVA: diva2:947160
Public defence
2016-09-16, Hamberg, Villavägen 16, Uppsala, 13:15 (English)
Opponent
Supervisors
Available from: 2016-08-24 Created: 2016-03-01 Last updated: 2016-08-26
List of papers
1. Effects of permeability heterogeneity on CO2 injectivity and storage efficiency coefficient
Open this publication in new window or tab >>Effects of permeability heterogeneity on CO2 injectivity and storage efficiency coefficient
2016 (English)In: Greenhouse Gases: Science and Technology, E-ISSN 2152-3878, Vol. 6, no 1, 112-124 p.Article in journal (Refereed) Published
Abstract [en]

We study the dependency of CO2 storage efficiency coefficient (E) and injectivity index (Iinj) on the geostatistical parameters of the permeability field. CO2 injection simulations are conducted for multiple realizations of log-normally distributed permeability fields parameterized by log permeability standard deviation (𝜎) and dimensionless horizontal correlation length (𝜆). Results show that the injectivity index increases with increasing 𝜆, the magnitude of the effect depending on 𝜎. Increasing 𝜎 leads to poorer injectivity for cases with small 𝜆, but improves injectivity when 𝜆 is large. Further analysis indicates that the enhancing effect of 𝜎 on injectivity can be attributed to cases with channelized flow, while the decrease effect of 𝜎 is seen in more dispersive flow regime. The dependence of injectivity on both 𝜆 and 𝜎 is captured with a linear correlation between Iinj and a parameter group (𝜆/ξ)𝜎, where ξ is a dimensionless scaling parameter. The storage efficiency coefficient, on the other hand, decreases with both increasing 𝜎 and 𝜆, and a simple linear fit is found between E and the parameter group 𝜆𝜎2, a well-established heterogeneity parameter group describing e.g. macro-dispersivity in solute transport studies. The above relationships provide potentially useful tools for preliminary evaluation of a site. Future studies should address the validity of the relationships in alternative injection scenarios and domain geometries.

Keyword
CO2 sequestration; storage capacity; injectivity; permeability heterogeneity; numerical simulation
National Category
Oceanography, Hydrology, Water Resources Geophysical Engineering
Identifiers
urn:nbn:se:uu:diva-279379 (URN)10.1002/ghg.1540 (DOI)000369976400010 ()
Funder
EU, FP7, Seventh Framework Programme, MustangEU, FP7, Seventh Framework Programme, PanaceaSwedish National Infrastructure for Computing (SNIC), p2007023
Available from: 2016-03-03 Created: 2016-03-01 Last updated: 2016-08-26Bibliographically approved
2. Upscaling of the constitutive relationships for CO2 migration in multimodal heterogeneous formations
Open this publication in new window or tab >>Upscaling of the constitutive relationships for CO2 migration in multimodal heterogeneous formations
2013 (English)In: International Journal of Greenhouse Gas Control, ISSN 1750-5836, Vol. 19, 743-755 p.Article in journal (Refereed) Published
Abstract [en]

Numerical modeling is a critical tool for site performance and risk assessment of geological stored CO2 at the reservoir scale. However, due to computational resource constraints, reservoir scale models have limitations in accounting for the details of the multi-scale heterogeneities. Appropriately averaged medium parameters are needed for the full scale modeling. In this study, we apply the macroscopic theory and present large-scale capillary pressure–relative permeability–saturation relationships that may be used as grid-block properties in the full-scale modeling. A macroscopic invasion percolation (MIP) model is developed, based on the assumption of capillary force dominance. Comparison of the MIP model with the numerical simulator TOUGH2/ECO2N for simulations of large-scale drainage capillary pressure curves shows a reasonably good match between results from the two models. Large-scale constitutive relationships are obtained through simulation procedures of CO2 displacing brine in multimodal heterogeneous media for ten cases with different geostatistical parameters. The large-scale constitutive relationships are mainly controlled by the proportion and the permeability variability of the background (framework) material, while the existence of the non-framework materials and their permeability variabilities may contribute, in a complex way, to the uncertainty in the large-scale constitutive relationships. In addition, the Leverett equation may well describe the relationship between the large-scale capillary pressure and absolute permeability when the sandstone (background material) proportion is high (>0.7). For cases with smaller sandstone proportions it may not be appropriate to link capillary pressure and absolute permeability through the Leverett equation.

National Category
Geosciences, Multidisciplinary
Identifiers
urn:nbn:se:uu:diva-184833 (URN)10.1016/j.ijggc.2012.11.015 (DOI)000332396700012 ()
Available from: 2012-11-15 Created: 2012-11-15 Last updated: 2016-08-26Bibliographically approved
3. Gaussian Process Emulators for Quantifying Uncertainty in CO2 Spreading Predictions in Heterogeneous Media
Open this publication in new window or tab >>Gaussian Process Emulators for Quantifying Uncertainty in CO2 Spreading Predictions in Heterogeneous Media
Show others...
(English)Manuscript (preprint) (Other academic)
Abstract [en]

We explore the use of Gaussian process emulators (GPE) in the numerical simulationof CO2 injection into a deep heterogeneous aquifer. The model domainis an uncertain two-dimensional log-normally distributed permeability eld. Weestimate the cumulative distribution functions (CDF) of the CO2 breakthroughtime and the total mass using a computationally expensive Monte Carlo (MC)simulation. We then show that we can accurately reproduce these CDF estimateswith a GPE, but using only a fraction of the computational cost comparedto Monte Carlo. In order to build a GPE that can predict the simulator outputfrom a permeability eld consisting of 1000s of values, we use a truncatedKarhunen-Loève expansion of the permeability eld, and then use a Bayesianfunctional regression approach. We explore issues encountered in using GPEsin uncertainty analyses of CO2 storage problems, including the optimization ofthe experiment design, and provide perspectives for future applications.

Keyword
CO2, Bayesian, Permeability, KL expansion, Monte Carlo, Cumulative distribution function, Uncertainty analysis
National Category
Geosciences, Multidisciplinary
Identifiers
urn:nbn:se:uu:diva-298748 (URN)
Funder
EU, FP7, Seventh Framework Programme, 227286EU, FP7, Seventh Framework Programme, 282900EU, FP7, Seventh Framework Programme, 309067
Available from: 2016-07-06 Created: 2016-07-06 Last updated: 2016-08-26
4. Integrated simulations of CO2 spreading and pressure response in the multilayer saline aquifer of South Scania Site, Sweden
Open this publication in new window or tab >>Integrated simulations of CO2 spreading and pressure response in the multilayer saline aquifer of South Scania Site, Sweden
Show others...
2016 (English)In: Greenhouse Gases: Science and Technology, E-ISSN 2152-3878, GHG1583Article in journal (Refereed) Accepted
Abstract [en]

An integrated modeling approach/workflow, in which a series of mathematical models of different levels of complexity are applied to evaluate the geological storage capacity of the Scania Site, southwest Sweden, is presented. The storage formation at the site is a layered formation limited by bounding fault zones, and injection is assumed to take place from one existing deep borehole into all layers. A semi-analytical model for two-phase flow is first used to evaluate the pressure response and related parameter sensitivity, as well as the first estimates of acceptable injection rates. These results are then used to guide the more detailed numerical simulations that address both pressure response and plume migration. The vertical equilibrium (VE) model is used to obtain a preliminary understanding of the plume migration with a larger number of simulations. Finally the full TOUGH2/ECO2N simulations are performed for the most detailed analyses of pressure responses and plume migration. Throughout, the results of the different modeling approaches are compared against each other. It is concluded that the key limiting factor for the storage capacity at the site in the injection scenario considered is the fast CO2 migration within the high permeability layer. Future studies can address alternative injection scenarios, including horizontal injection wells and injection to other layers than the high permeability layer.

Keyword
CO2; Geological storage; Storage capacity; Injectivity; Numerical simulation; Semi-analytical solution; Vertical equilibrium
National Category
Oceanography, Hydrology, Water Resources Geophysical Engineering
Identifiers
urn:nbn:se:uu:diva-279718 (URN)10.1002/ghg.1583 (DOI)
Funder
EU, FP7, Seventh Framework Programme, MustangEU, FP7, Seventh Framework Programme, PanaceaEU, FP7, Seventh Framework Programme, Trust
Available from: 2016-03-03 Created: 2016-03-03 Last updated: 2016-08-26
5. Assessing CO2 storage capacity in the Dalders Monocline of the Baltic Sea Basin using dynamic models of varying complexity
Open this publication in new window or tab >>Assessing CO2 storage capacity in the Dalders Monocline of the Baltic Sea Basin using dynamic models of varying complexity
Show others...
2015 (English)In: International Journal of Greenhouse Gas Control, Vol. 43, 149-150 p.Article in journal (Refereed) Published
Abstract [en]

The first dynamic modeling study of CO2 geological storage in the Baltic Sea basin is presented. The focus has been on the southern part of the Dalders Monocline. The objective is to get order-of-magnitude estimates of the behavior of the formations during potential industrial scale CO2 injection and subsequent storage periods, with an emphasis on two important aspects of CO2 storage: the injection-induced pressure impact and the long-term upslope migration. In order to maximize the confidence in the model predictions, this work employs a set of different modeling approaches of varying complexity, including a semi-analytical model, a sharp-interface vertical equilibrium (VE) model and a TOUGH2-ECO2N model. The semi-analytical model provides fast estimation of the pressure buildup as well as its sensitivity to variation of the reservoir parameters. Given a certain pressure threshold, a maximum injection rate is estimated from the semi-analytical model and is then fed to the numerical models. The pressure buildup predicted by the numerical models fall close to that by the semi-analytical solution. Extensive modeling of the post-injection upslope migration and trapping evolution together with sensitivity analysis suggests that it is unlikely for CO2 to leak through the north end of the formation. Under the currently considered scenario, the dominant constraint for the storage capacity is the pressure buildup. The pressure limited capacity (Cp) of the southern Dalders Monocline for the scenario studied here is estimated to be about 100 Mt for a 50-year injection duration. Cp is found to increase with permeability as Cp ∼ k0.926. Given the knowledge of the dominant constraint for capacity, storage optimization can be specifically targeted on the injectivity issue and operational strategies can be designed to relieve the pressure buildup (e.g., by adding brine production wells, using horizontal wells).

Keyword
CO2 sequestration; Storage capacity; Numerical modeling; Semi-analytical solution; Vertical equilibrium
National Category
Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:uu:diva-270275 (URN)10.1016/j.ijggc.2015.10.024 (DOI)000367110200015 ()
Funder
Swedish Energy AgencyEU, FP7, Seventh Framework Programme, 227286EU, FP7, Seventh Framework Programme, 282900Swedish Research Council
Available from: 2015-12-22 Created: 2015-12-22 Last updated: 2016-08-26Bibliographically approved

Open Access in DiVA

fulltext(3091 kB)46 downloads
File information
File name FULLTEXT01.pdfFile size 3091 kBChecksum SHA-512
d7c1484042fd5b2e6eeeb6a5fe14708814a12ccb6d9fd0db44053eef8e2d58604ec769ff2b39f509ca4949bd545063814325b21251148acec2414bc0467ee038
Type fulltextMimetype application/pdf
Buy this publication >>

Search in DiVA

By author/editor
Tian, Liang
By organisation
LUVAL
Geosciences, Multidisciplinary

Search outside of DiVA

GoogleGoogle Scholar
Total: 46 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 360 hits
ReferencesLink to record
Permanent link

Direct link