Song Yongchen, Jiang Lanlan, Liu Yu, Yang Mingjun, Zhou Xinhuan, Zhao Yuechao, Dou Binlin, Abudula Abuliti, Xue Ziqiu
Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education, Dalian University of Technology, Dalian, Liaoning 116024, China.
Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education, Dalian University of Technology, Dalian, Liaoning 116024, China.
Magn Reson Imaging. 2014 Jun;32(5):574-84. doi: 10.1016/j.mri.2014.01.021. Epub 2014 Feb 3.
The objective of this study was to understand fluid flow in porous media. Understanding of fluid flow process in porous media is important for the geological storage of CO2. The high-resolution magnetic resonance imaging (MRI) technique was used to measure fluid flow in a porous medium (glass beads BZ-02). First, the permeability was obtained from velocity images. Next, CO2-water immiscible displacement experiments using different flow rates were investigated. Three stages were obtained from the MR intensity plot. With increasing CO2 flow rate, a relatively uniform CO2 distribution and a uniform CO2 front were observed. Subsequently, the final water saturation decreased. Using core analysis methods, the CO2 velocities were obtained during the CO2-water immiscible displacement process, which were applied to evaluate the capillary dispersion rate, viscous dominated fractional flow, and gravity flow function. The capillary dispersion rate dominated the effects of capillary, which was largest at water saturations of 0.5 and 0.6. The viscous-dominant fractional flow function varied with the saturation of water. The gravity fractional flow reached peak values at the saturation of 0.6. The gravity forces played a positive role in the downward displacements because they thus tended to stabilize the displacement process, thereby producing increased breakthrough times and correspondingly high recoveries. Finally, the relative permeability was also reconstructed. The study provides useful data regarding the transport processes in the geological storage of CO2.
本研究的目的是了解多孔介质中的流体流动。了解多孔介质中的流体流动过程对于二氧化碳的地质封存很重要。采用高分辨率磁共振成像（MRI）技术测量多孔介质（玻璃珠BZ - 02）中的流体流动。首先，从速度图像中获得渗透率。接下来，研究了使用不同流速的二氧化碳 - 水不混溶驱替实验。从磁共振强度图中得到三个阶段。随着二氧化碳流速的增加，观察到相对均匀的二氧化碳分布和均匀的二氧化碳前缘。随后，最终水饱和度降低。使用岩心分析方法，获得了二氧化碳 - 水不混溶驱替过程中的二氧化碳速度，这些速度被用于评估毛管弥散率、粘性主导的分流率和重力流函数。毛管弥散率主导了毛管效应，在水饱和度为0.5和0.6时最大。粘性主导的分流率函数随水饱和度而变化。重力分流率在饱和度为0.6时达到峰值。重力在向下驱替中起到了积极作用，因为它们倾向于稳定驱替过程，从而产生更长的突破时间和相应更高的采收率。最后，还重建了相对渗透率。该研究提供了关于二氧化碳地质封存中传输过程的有用数据。
