Controlling potential far‐field brine leakage from CO 2 storage formations using deep extraction wells: Numerical and experimental testing
Controlling potential far‐field brine leakage from CO 2 storage formations using deep extraction wells: Numerical and experimental testing
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DOI：
10.1002/ghg.2194
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发表时间：
2022-12
期刊：
影响因子：
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通讯作者：
A. H. Askar;T. Illangasekare
中科院分区：
文献类型：
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作者：
A. H. Askar;T. Illangasekare
将二氧化碳注入深层地质层以进行封存会导致巨大的压力积聚，从而危及盖层的完整性。盖层中自然发生的断层或压力引起的裂缝可以作为传导泄漏路径，导致上覆浅层含水层的潜在污染。之前的研究探索了利用盐水提取来控制储存地层中的这种高压。在本文中，我们扩展了该技术的使用来控制远场盐水泄漏。提取井位于储存区，通过局部反转压力梯度来减少泄漏流量，同时利用上覆地层的稀释能力最大限度地减少逃逸部分中的盐水浓度。开发的方法将遗传算法与传输模型模拟相结合，以优化井位和开采率。由于无法获得现场数据，因此使用了一个约 8 m 长的中型储罐来模拟现场盐水泄漏迁移，以验证该方法。我们使用圣华金盆地 Vedder 储层的假设泄漏场景进一步对该方法进行了数值评估，以评估其现场实施的实用性。结果表明，储层非均质性和裂缝渗透率会显着影响抽采井的最佳位置和抽油量。盐水泄漏可以通过提取少于注入 CO2 体积 50% 的天然盐水体积来控制。浅层含水层中的目标浓度决定了控制裂缝或埋藏逆冲断层泄漏所需的提取率。该研究有助于制定碳储存作业的修复策略。 © 2022 化学工业协会和 John Wiley & Sons, Ltd.
Injecting CO2into deep geologic formations for storage purposes induces large pressure build‐up that risks caprock integrity. Naturally occurring faults or pressure‐induced fractures in the caprock can act as conductive leakage pathways resulting in potential contamination of the overlying shallow aquifers. Previous studies explored using brine extraction to manage such elevated pressure in the storage formation. In this paper, we extended the use of this technique to control far‐field brine leakage. Extraction wells are placed in the storage zone to reduce the leakage flow through reversing the pressure‐gradient locally, while minimizing the brine concentrations in the escaped‐fraction by utilizing the dilution capacity of the overlying formations. The developed approach incorporated the Genetic Algorithm with transport model simulations to optimize well‐placements and extraction‐rates. An approximately 8m long intermediate‐scale tank designed to mimic brine leakage migration in the field was used to validate this approach as field data are not available. We further evaluated the approach numerically using a hypothetical leakage scenario at the Vedder storage formation in San‐Joaquin basin to assess its practicality for field implementation. The results showed that storage zone heterogeneity and fractures’ permeabilities can significantly affect the optimum locations and pumping rates of the extraction wells. Brine leakage can be controlled by extracting a native‐brine volume less than 50% of the injected CO2volume. The target concentrations in the shallow aquifer determines the extraction rates required to control a leakage through a fracture or a buried thrust fault. The study is useful to develop remediation strategies for carbon storage operations. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd.