Saturation comparison of CO2 containing N2 at different injection velocities and conditions by X-ray CT scanning

Abstract Understanding the residual trapping mechanisms is important to design successful CO 2 storage projects. CO 2 injected in field sequestration site are usually combined with various kinds of impurities. N 2 is the most common component, occupying the highest proportion and relatively large cost for gas separating and purification system. The objective of this study was to concentrate the impact of N 2 content ratio and flow rate on the saturation of CO 2 &N 2 gas mixture for a further economical CO 2 separation and sequestration. The gas mixture is almost homogeneous while the total saturations are higher at two conditions: higher CO 2 proportion with lower flow rate, and lower CO 2 proportion with higher flow rate. Meanwhile, saturation maps at different temperature and pressure have certain differences though some of the fluid properties are almost same. Thus experiments between such conditions are not replaceable as the properties of gases will induce the hydrological and hydraulic variation of flow path.