Study on Factors Affecting CO2 Recovery of Fractured Pressure-sensitive Reservoirs

Authors : Yueli FENG, Yuetian LİU, Jie DONG, Jian CHEN, Jianshu HUANG

Pages : 22-25

View : 14 | Download : 11

Publication Date : 2017-12-31

Article Type : Conference Paper

Abstract :The different deformation degree of fractures caused by the intrinsic strong pressure-sensitive property of the ultra-low permeability reservoirs would change the channeling law of CO 2 in fractures, then affect the oil displacement efficiency. Thus, revealing the seepage characteristics of CO 2 in fractured reservoirs is the groundwork to improve the oil displacement efficiency of CO 2 . The directional pressure-sensitive property of fractures was simulated by a physical model. The simulation of physical experiment with multi-physics coupling was carried out by theoretical derivation and finite element analysis software COMSOL Multiphysics. The stronger heterogeneity of reservoirs , makes CO 2 much easier to rush. Increasing injection pressure , can increase the proportion of CO 2 in low permeability area. As the pressure-sensitive property between high and low permeability layer is different, increasing the effective stress would induce stronger heterogeneity. Therefore, in order to control the effect of pressure-sensitive property on production，the formation pressure should be controlled reasonably in development process. In this study, the factors, especially the fracture development directions, which show significant influence on the oil recovery of CO 2 flooding in fractured and pressure-sensitive reservoirs, were studied with physical experiments and numerical experiments. The results obtained in the study can provide a more reliable theoretical basis for CO 2 flooding design and profile control technology.
Keywords : CO2 flooding, pressure sensitive, fracture direction