Muller N.,Cooperative Research Center for Greenhouse Gas Technologies
Transport in Porous Media | Year: 2011
The relative permeability of carbon dioxide (CO2) to brine influences the injectivity and plume migration when CO2 is injected in a reservoir for CO2 storage or enhanced oil recovery (EOR) purposes. It is common practice to determine the relative permeability of a fluid by means of laboratory measurements. Two principal approaches are used to obtain a relative permeability data: steady state and unsteady state. Although CO2 has been employed in enhanced oil recovery, not much data can be found in the open literature. The few studies available report wide ranges for CO2 relative permeability in typical sedimentary rocks such as Berea sandstone, dolomite, and others. The experimental setups vary for each study, employing steady and unsteady state approaches, different experimental parameters such as temperature, pressure, rock type, etc. and various interpretation methods. Hence, it is inherently difficult to compare the data and determine the origin of differences. It is evident that more experiments are needed to close this knowledge gap on relative permeability. This article concludes that standards for lab measurements need to be defined a. to establish a reliable CO2-brine relative permeability measurement method that can be repeated under the same conditions in any lab and b. to enable comparison of the data to accurately predict the well injection and fluid migration behavior in the reservoir. © 2010 Springer Science+Business Media B.V.
Webley P.A.,Cooperative Research Center for Greenhouse Gas Technologies
Adsorption | Year: 2014
The capture of CO2 from process and flue gas streams and subsequent sequestration was first proposed as a greenhouse gas mitigation option in the 1990s. This proposal spawned a series of laboratory and field tests in CO2 capture which has now grown into a major world-wide research effort encompassing a myriad of capture technologies and ingenious flow sheets integrating power production and carbon capture. Simultaneously, the explosive growth in materials science in the last two decades has produced a wealth of new materials and knowledge providing us with new avenues to explore to fine tune CO2 adsorption and selectivity. Laboratory and field studies over the last decade have explored the synergy of process and materials to produce numerous CO2 capture technologies and materials based on cyclic adsorption processes. In this brief perspective, we look at some of these developments and comment on the application and limitations of adsorption process to CO2 capture. We identify major engineering obstacles to overcome as well as potential breakthroughs necessary to achieve commercialization of adsorption processes for CO2 capture. Our perspective is primarily restricted to post-combustion flue gas capture and CO2 capture from natural gas. © 2014 Springer Science+Business Media New York.
Lwin M.J.,Cooperative Research Center for Greenhouse Gas Technologies
Geophysics | Year: 2011
To gauge the potential of seismic methods for the estimation of gas content in coal, the ultrasonic response of a sample saturated in turn with He, N2, CH4, and CO2 has been investigated. Specifically, traveltimes were used to determine P-wave velocity as a function of the difference between confining pressure and pore pressure. After crushing the sample to powder, adsorption isotherms for CO2 and CH4 were measured and then used to estimate the bulk densities, P-wave moduli, and impedances during the traveltime measurements. The data suggest a significant difference in density, P-wave modulus, and impedance under CO2 relative to CH4 saturation. Though these findings are based on the assumption that adsorption capacity of the sample when confined was similar to that measured after crushing, they are also roughly supported by isostatic strain measurements taken during swelling. Two possible causes of this behavior are, first, the mechanical properties of the adsorbed phase may be more liquid than gaslike. Second, the swelling of coal under confining pressure should lead to the closure of soft pores, thus stiffening the frame. © 2011 Society of Exploration Geophysicists.
LaForce T.C.,Cooperative Research Center for Greenhouse Gas Technologies
Computational Geosciences | Year: 2012
In this work, the analytical and numerical solutions for modeling miscible gas and water injection into an oil reservoir are presented. Conservation laws with three levels of complexity are considered. Only the most complex model has the correct phase behavior for the example system, which is a multicontact miscible condensing gas drive with simultaneous water and gas injection. Example displacements in which one or both of the simpler models result in accurate simulations in a fraction of the computation time are presented, along with an example in which neither simplified thermodynamic model achieves a truly satisfactory result. A methodology is presented that can be used to establish the accuracy of simplified models in 1-D simulation based on convergence to analytical solutions for the full three-phase system. © 2012 Springer Science+Business Media B.V.
Jenkins C.,Cooperative Research Center for Greenhouse Gas Technologies
International Journal of Greenhouse Gas Control | Year: 2013
Statistical methods will be important tools in the monitoring of CO2 storage sites, because any signals of leakage are likely to be small compared with measurement and modelling error and natural variability. To conclude that there is no leakage at a storage site necessarily involves consideration of leakage models, as proving " no leakage" as an isolated proposition is impossible. It is important in the circumstances of carbon capture and storage (CCS) to have clear and reproducible methods for testing leakage and no-leakage models against each other in the light of data, and some statistical methods are more useful than others in achieving this. This article reviews three broad approaches to the statistical interpretation of data containing a small leakage signal, with the objective of clarifying the concepts involved for practitioners in CCS who are not statisticians. Bayesian methods are given particular emphasis because they most clearly answer the questions that stakeholders ask, and give a natural framework for dealing with a comprehensive suite of models. The nature and importance of baseline data is discussed in the context of statistical interpretation of monitoring data. © 2013 .