Exploring the Impacts of Source Condition Uncertainties on Far‐Field Brine Leakage Plume Predictions in Geologic Storage of CO2: Integrating Intermediate‐Scale Laboratory Testing With Numerical Modeling
Exploring the Impacts of Source Condition Uncertainties on Far‐Field Brine Leakage Plume Predictions in Geologic Storage of CO2: Integrating Intermediate‐Scale Laboratory Testing With Numerical Modeling
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DOI：
10.1029/2021wr029679
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发表时间：
2021-08
影响因子：
5.4
通讯作者：
A. H. Askar;T. Illangasekare;A. Trautz;J. Solovský;Ye Zhang;R. Fučík
中科院分区：
文献类型：
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作者：
A. H. Askar;T. Illangasekare;A. Trautz;J. Solovský;Ye Zhang;R. Fučík
限制注入二氧化碳的盖层天然裂缝/断层或压力诱发裂缝已被确定为远场天然盐水污染地下饮用水源的潜在泄漏途径。开发模型来模拟盐水在上覆地层和含水层中的传播，对于分别进行选址和运营的可靠的风险前和风险后评估至关重要。进行此类模拟的主要挑战之一是缺乏足够的来源条件信息，例如盖层破裂/断裂带的水力构造特性和储层的渗透率场。本文研究了源条件的不确定性对泄漏盐水羽流预测精度的影响。预测模型应该能够模拟复杂的多层地质系统中区域自然流和泄漏流相互作用的盐水泄漏和运移。由于现场数据集不容易用于模型测试和验证，因此使用三个综合的中尺度实验室实验来生成不同泄漏情景下盐水羽流发展的高分辨率时空数据。实验数据用于验证利用现有代码FEFLOW开发的流动和输运模型，以模拟不同源条件下的盐水羽流。空间矩分析用于评估源条件的不确定性如何影响盐水迁移预测。结果表明，模型中对储层和盖层裂缝渗透率场的不准确描述会导致泄漏路径和预测误差分别高达~ 19%和~ 100%。这些发现将有助于通过考虑对浅层地下水资源的潜在风险来选择和确定储存地点。
Natural fissures/faults or pressure‐induced fractures in the caprock confining injected CO2 have been identified as a potential leakage pathways of far‐field native brine contaminating underground sources of drinking water. Developing models to simulate brine propagation through the overlaying formations and aquifers is essential to conduct reliable pre‐ and post‐risk assessments for site selection and operation, respectively. One of the primary challenges of performing such simulations is lack of adequate information about source conditions, such as hydro‐structural properties of caprock fracture/fault zone and the permeability field of the storage formation. This research investigates the impact of source condition uncertainties on the accuracy of leaking brine plume predictions. Prediction models should be able to simulate brine leakage and transport in complex multilayered geologic systems with interacting regional natural and leakage flows. As field datasets are not readily available for model testing and validation, three comprehensive intermediate‐scale laboratory experiments were used to generate high‐resolution spatiotemporal data on brine plume development under different leakage scenarios. Experimental data were used to validate a flow and transport model developed using existing code FEFLOW to simulate brine plume under varying source conditions. Spatial moment analysis was conducted to evaluate how uncertainty in source conditions impacts brine migration predictions. Results showed that inaccurately prescribing the permeability field of storage formation and caprock fractures in models can cause errors in leakage pathway and spread predictions up to ∼19% and ∼100%, respectively. These findings will help in selecting and characterizing storage sites by factoring in potential risks to shallow groundwater resources.