Numerical investigation of basin‐scale storage of CO 2 in saline aquifers of Songliao Basin, China

This paper presents a basin‐scale model study of the behaviors of CO 2 plume and the potential environmental impacts for large‐scale CO 2 storage in the saline aquifers of Songliao Basin, China. The model covers the whole basin, and vertically consists of most of the Cretaceous strata. In a hypothetical scenario, a total of 1.43 GT CO 2 is injected into the Yaojia Formation (K 2 y) through 20 wells distributing at the center of the basin in 50 years (0.5–2 million tons per injection well per year). The preliminary results show the permeable Yaojia Formation (K 2 y) with a thickness of 100–400 m at the center of the basin can store large amounts of CO 2 . The overlying Nenjiang Formation (K 2 n) with low permeability and large thickness has the potential to ensure long‐term storage security. The high solubility of CO 2 of the formation water in this continental basin is a favorable condition for the storage security. The maximum extent of the CO 2 plume from different injection wells ranges from about 4 km to 20 km at 1000 years. The maximum pressure build‐up in the Nenjiang Formation (K 2 n) and the Yaojia Formation (K 2 y) reaches 8.6 MPa and 9.3 MPa, respectively. An entry capillary pressure of 1 MPa may be enough for the caprock to seal CO 2 in the large‐scale CO 2 storage. The mudstone layers in the Nenjiang Formation (K 2 n) can play a crucial role in restraining upward brine migration.© 2014 Society of Chemical Industry and John Wiley & Sons, Ltd