Key Laboratory of Petroleum Engineering of MOE, China University of Petroleum , Beijing 102249, People's Republic of China.
Environ Sci Technol. 2013 Sep 3;47(17):10071-7. doi: 10.1021/es4017409. Epub 2013 Aug 16.
CO2 sequestration has been considered to be one of the most straightforward carbon management strategies for industrial CO2 emission. Monitoring of the CO2 injection process is one of the best ways to make sure the safety storage but is also a major challenge in CO2 geological sequestration. Previous field and laboratory researches have shown that seismic methods are among the most promising monitoring methods because of the obvious reduction in P-wave velocities caused by CO2 injection. However, as CO2 injection continues, the P-wave velocity becomes increasingly insensitive according to the pilot projects when CO2 saturation is higher than 20-40%. Therefore, the conventional seismic method needs improvement or replacement to solve its limitations. In this study, P-wave velocity and amplitude responses to supercritical CO2 injection in brine-saturated core samples from Jilin oilfield were tested using core displacement and an ultrasonic detection integrated system. Results showed that neither the P-wave velocity nor amplitude could simply be used to monitor the CO2 injection process because of the insensitive or nonmonotonous response. Consequently, a new index was established by synthetically considering these two parameters to invert and monitor the CO2 process, which can be thought of as a newer and more effective assessment criterion for the seismic method.
CO2 捕集被认为是工业 CO2 排放的最直接的碳管理策略之一。监测 CO2 注入过程是确保安全储存的最佳方法之一，但也是 CO2 地质封存的主要挑战之一。先前的现场和实验室研究表明，地震方法是最有前途的监测方法之一，因为 CO2 注入会导致明显的 P 波速度降低。然而，根据试点项目，当 CO2 饱和度高于 20-40%时，随着 CO2 注入的继续，P 波速度会变得越来越不敏感。因此，需要改进或替换传统的地震方法来解决其局限性。在这项研究中，使用岩心驱替和超声检测集成系统，对来自吉林油田的饱盐水岩心样品中超临界 CO2 注入的 P 波速度和振幅响应进行了测试。结果表明，由于响应不敏感或非单调，P 波速度和振幅都不能简单地用于监测 CO2 注入过程。因此，通过综合考虑这两个参数，建立了一个新的指标来反演和监测 CO2 过程，这可以被认为是地震方法的一个更新、更有效的评估标准。
