Alhosani Abdulla, Scanziani Alessio, Lin Qingyang, Selem Ahmed, Pan Ziqing, Blunt Martin J, Bijeljic Branko
Department of Earth Science and Engineering, Imperial College London, London, UK.
State Environmental Protection Engineering Center for Coal-Fired Air Pollution Control, Zhejiang University, Hangzhou 310027, People's Republic of China.
Proc Math Phys Eng Sci. 2020 Dec;476(2244):20200671. doi: 10.1098/rspa.2020.0671. Epub 2020 Dec 23.
We use synchrotron X-ray micro-tomography to investigate the displacement dynamics during three-phase-oil, water and gas-flow in a hydrophobic porous medium. We observe a distinct gas invasion pattern, where gas progresses through the pore space in the form of disconnected clusters mediated by double and multiple displacement events. Gas advances in a process we name three-phase Haines jumps, during which gas re-arranges its configuration in the pore space, retracting from some regions to enable the rapid filling of multiple pores. The gas retraction leads to a permanent disconnection of gas ganglia, which do not reconnect as gas injection proceeds. We observe, , the direct displacement of oil and water by gas as well as gas-oil-water double displacement. The use of local measurements and an energy balance approach to determine fluid-fluid contact angles alongside the quantification of capillary pressures and pore occupancy indicate that the wettability order is oil-gas-water from most to least wetting. Furthermore, quantifying the evolution of Minkowski functionals implied well-connected oil and water, while the gas connectivity decreased as gas was broken up into discrete clusters during injection. This work can be used to design CO storage, improved oil recovery and microfluidic devices.
我们使用同步加速器X射线显微断层扫描技术来研究疏水多孔介质中油、水、气三相流过程中的驱替动力学。我们观察到一种独特的气体侵入模式，即气体以由双重和多重驱替事件介导的离散团簇形式在孔隙空间中推进。气体以我们称为三相海恩斯跳跃的过程推进，在此过程中气体在孔隙空间中重新排列其构型，从某些区域缩回以使多个孔隙能够快速填充。气体缩回导致气体节块永久断开连接，随着气体注入的进行，这些节块不会重新连接。我们还观察到气体对油和水的直接驱替以及气-油-水双重驱替。使用局部测量和能量平衡方法来确定流体-流体接触角，同时对毛细管压力和孔隙占有率进行量化，结果表明润湿性顺序为油-气-水，从最湿润到最不湿润。此外，对闵可夫斯基泛函的演化进行量化表明油和水具有良好的连通性，而在注入过程中，随着气体被分解成离散团簇，气体的连通性降低。这项工作可用于设计二氧化碳封存、提高石油采收率和微流控装置。
