A 2-D model of CO2 disposal into deep saline aquifers: case study of the Songliao Basin, China

摘要

The injection of CO2 into deep saline aquifers is considered as a promising approach to reduce CO2 emissions into atmosphere. Numerical modeling is an important and powerful tool for studying the effects of the injection of CO2 into saline aquifers. A case study of the Songliao Basin, China is presented by using the numerical module of TOUGH2. Firstly, based on the preliminary study of geological formation in the Songliao Basin, the Cretaceous Yaojia formation is selected as the suitable aquifer for CO2 storage. Then, an ideal two-dimensional model is set up to characterize the injection of CO2 into the Yaojia formations in which the permeability and porosity changed with depth. The migration, the storage capacity, and the phase changes of CO2 after injection are studied in detail by numerical modeling. Besides, the parameters sensitivity analysis is carried out, which includes the residual gas saturation, the ratio of vertical to horizontal permeability, and so on. Therefore, the impacts of different factors on CO2 disposal into saline aquifers are evaluated.