1 © 2014 Society of Chemical Industry and John Wiley & Sons, Ltd | Greenhouse Gas Sci Technol. 1–14 (2014); DOI: 10.1002/ghg Received June 4, 2014; revised July 17, 2014; accepted July 18, 2014 Published online at Wiley Online Library (wileyonlinelibrary.com). DOI: 10.1002/ghg.1466 Modeling and Analysis Modeling of pressure build-up and estimation of maximum injection rate for geological CO 2 storage at the South Scania site, Sweden Zhibing Yang , Auli Niemi , Liang Tian , and Saba Joodaki , Uppsala University, Sweden Mikael Erlström , Geological Survey of Sweden, Lund, Sweden Abstract: Carbon dioxide (CO 2 ) injection in deep saline formations causes pressure increase which may be detrimental to the mechanical integrity of the storage reservoir. Injection induced pressure build-up is a limiting factor for CO 2 injection rates and storage capacity. In this study, we extend a semi-analytical solution (based on one-dimensional, two-phase, two-component radial flow) for appli- cation to estimate pressure build-up and maximum injection rate of CO 2 at a field site (South Scania, Sweden) using the method of superposition of image well solutions to account for the straight-line boundaries imposed by three fault zones. The semi-analytical approach for estimating pressure build- up is validated by comparison to numerical simulations based on TOUGH2-ECO2N. We analyze injection pressure sensitivity due to uncertainty in reservoir parameters as well as boundary conditions. Maximum injection rates and pressure limited capacity estimates are presented. This work demon- strates the use of semi-analytical solutions to analyze pressure limitation on storage capacity for realistic reservoirs with irregular (non-circular) boundaries. It is also shown that the semi-analytical approach can also be used to evaluate the benefit of having multiple injection wells in terms of increas- ing the injection-pressure-limited storage capacity. The methodology presented in this study is useful for screening analysis of storage sites as well as for operation design and optimization where pressure build-up as a limiting factor influences the objective function. © 2014 Society of Chemical Industry and John Wiley & Sons, Ltd Keywords: geological storage; pressure-limited capacity; numerical modeling; analytical solution; mechanical failure Correspondence to: Zhibing Yang, Department of Earth Sciences, Uppsala University, Villavägen 16, SE-752 36 Uppsala, Sweden. E-mail: zhibing.yang@hyd.uu.se Introduction R eduction of atmospheric greenhouse gas concen- trations can be achieved by carbon capture and storage (CCS). Implementation of CCS requires sequestrating a large amount of carbon dioxide (CO 2 ) preferably in the deep saline formations. For closed formations, the pore space needed for storing CO 2 is accommodated by enlargement of the rock pore space and at the same time reduction in the volume of the formation fuid, through compression of the rock material and the formation fuid, respectively. 1 For