Year: 2024
Type: article
Abstract: The characteristics of CO2 seepage in reservoirs have important research significance in the field of CCS technology application. However, the characteristics of macro-scale seepage are affected by the geometrical characteristics of micro-scale media, such as pore size and particle shape. Therefore, in this work, a series of numerical simulations were carried out using the phase field method to study the effect of pore structure simplification on micro-scale displacement process. The influences of capillary number, wettability, viscosity ratio, interfacial tension, and fracture development are discussed. The results show that the overall displacement patterns of the real pore model and the simplified particle model are almost similar, but the oil trapping mechanisms were totally different. There are differences in flow pattern, number of dominant flow channels, sensitivity to influencing factors and final recovery efficiency. The real pore model shows higher displacement efficiency. The decrease in oil wet strength of rock will change the CO2 displacement mode from pointing to piston displacement. At the same time, the frequency of breakage will be reduced, thus improving the continuity of CO2. When both pores and fractures are developed in the porous media, CO2 preferentially diffuses along the fractures and has an obvious front and finger phenomenon. When CO2 diffuses, it converges from the pore medium to the fracture and diverges from the fracture to the pore medium. The shape of fracture development in the dual medium will largely determine the CO2 diffusion pattern.
Source: Energies
DOI: 10.3390/en18010082
Authors: Tianjiang Wu, Changhao Yan, Ruiqi Gong, Yanhong Zhao, Xiaoyu Jiang, Liu Yang
Language: English
Subfield: Environmental Engineering
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,955
Awards: G8716543330, G986869646
OpenAlex ID: W4405974207