Large-scale numerical simulation of CO2 geologic storage and its impact on regional groundwater flow: A hypothetical case study at Tokyo Bay, Japan

With the help of massively parallelized computing techniques, a comprehensive, large-scale numerical simulation of CO2 geologic storage that predicts not only CO2 migration but also its impact on regional groundwater flow was performed. As a case study, a hypothetical industrial-scale injection of CO2 at the Tokyo Bay, surrounded by the most industrialized area in Japan, was considered. In the simulation, CO2 is injected into a storage aquifer at about 1km depths under the Tokyo Bay from 10 wells with a total rate of 10 million tons/year for 100 years. A regional hydrogeological model with an area of about 60km x 70km around the Tokyo Bay was discretized into approximately 10 million gridblocks. To solve the high-resolution model efficiently, we used a parallelized multiphase flow simulator TOUGH2-MP/ECO2N on a highest performance supercomputer in Japan, the Earth Simulator (5120 CPUs). The results suggest that even if containment of CO2 plume is ensured, pressure buildup in the order of tens of meters can occur in shallow confined layers of extensive regions including urban inlands. (C) 2009 Elsevier Ltd. All rights reserved.