Site-Level Carbon Storage Potential Estimation in Offshore China

Abstract To counteract the trend of global warming and to achieve the objective of "net zero emissions by 2050", many countries are conducting pilot research projects or experiments on carbon storage by exploring the technologies and practices for future deployment. One of the most critical elements for carbon storage is the storage capacity. Many previous authors have proposed their own methods to evaluate storage capacity in the saline aquifer environment, yet those methods are mainly designed for basin or depression-level evaluations. Because the methods vary from each other significantly make them impractical for a site-level storage capacity evaluation. The work this paper presents aims to estimate the storage capacity by means of a geoengineering approach in the site-level with an actual offshore China example. The key components of this approach include creating the geology and geomechanical model, evaluating the containment properties, and estimating the barrier stress conditions, etc. Considering the actual geology model properties and the dominant saline aquifer storage mechanisms, the authors chose multiple hot areas to conduct reservoir simulations with carbon dioxide injection, where saturation attack tactics were used to withdraw the storage efficiency factor and maximum capacity in different scenarios. This approach eventually allowed the authors to evaluate the true capacity of this site. This paper provides a systematic example of evaluating carbon storage capacity in the site level. The geoengineering approach also covers optimization of the injectivity and the containment of the barriers with an actual example, which is an important supplement to the existing carbon dioxide storage method, which focused mainly on the large-scale evaluation. Because this site-level workflow drops down to the actual geology and geomechanical environment, it may well prove better value towards the implementation of CO2 injection planning, operation, and monitoring in the later stages.