Experimental and modeling assessment of CO2 EOR and storage performances in tight oil reservoir, Yanchang oilfield, China

作者：Hong Yang, Heng Wang, Xiangzeng Wang, Yuchen Xin, Lilin He, Zunsheng Jiao, Jie Zou · 发表于：Journal of CO2 Utilization · 年份：2025 · DOI：10.1016/j.jcou.2025.103125 · 被引用次数：12 · 研究领域：CO2 Sequestration and Geologic Interactions、Reservoir Engineering and Simulation Methods、Enhanced Oil Recovery Techniques

Previous experimental studies have shown that CO 2 injections can significantly enhance oil recovery in tight oil reservoirs and sequestrate CO 2 permanently. However, performance varies in places when the technologies are scaled up in field pilot tests. Therefore, investigating CO 2 EOR (Enhanced Oil Recovery) and storage mechanisms during CO 2 injection in field-scale tight sandstone reservoirs is crucial. In this study, laboratory Pressure-Volume-Texperature (PVT) tests and field pilot tests of CO 2 injection in a tight oil reservoir of the Yanchang oilfield in the Ordos Basin were analyzed. Reservoir simulations of CO 2 injections, including continuous and water alternative gas injections, are conducted after history matching. Laboratory PVT results show that oil viscosity decreases from 5.10 to 2.38 mPa·s as pressure reduces from initial formation conditions to atmospheric pressure, and swells oil to 1.50 times at a saturation pressure of 240.0 bar, which is larger than the minimum miscible pressure of 178.0 bar from the slim tube test. Reservoir simulation results of continuous and WAG injection scenarios show that oil production increases with CO 2 injection rate, and oil recovery increments are 21.6 % and 19.3 %, respectively, for Case 3 and Case 5. This is because reservoir pressure increases with more injected CO 2 , resulting in higher displacement efficiency, and larger amounts of CO 2 can also lead to higher sweep efficiency in the lateral directions. However, CO...