Sealing Porous Media through Calcium Silicate Reactions with CO 2 to Enhance the Security of Geologic Carbon Sequestration
Sealing Porous Media through Calcium Silicate Reactions with CO 2 to Enhance the Security of Geologic Carbon Sequestration
复制标题
通过硅酸钙与CO 2 反应密封多孔介质以增强地质碳封存的安全性
DOI：
10.1089/ees.2020.0369
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发表时间：
2021
影响因子：
1.8
通讯作者：
Clarens, Andres F.
中科院分区：
文献类型：
--
作者：
Ling, Florence T.;Plattenberger, Dan A.;Peters, Catherine A.;Clarens, Andres F.
将二氧化碳注入地下深处，地质碳固存在减缓气候变化方面引起了相当大的关注。一个可靠的盖岩安全遏制是必不可少的，同时密封流动路径，以防止泄漏的战略。在这项研究中，我们探索的方式，其中CO2与CaSiO3的反应，可用于有针对性的矿物沉淀和渗透率控制原位。以前的工作表明，某些CaSiO3多晶型物可以产生孔隙填充沉淀，成功地抑制流动，而其他人产生沉淀，影响不大。在这项工作中，一维反应输运模型的厘米尺度系统，探索孔隙和连续体尺度之间的联系。该模型考虑了四个反应，涉及CaSiO3，CaCO3，SiO2（上午），和结晶硅酸钙水合物（CCSH）雪硅钙石。一个关键的特点是结合微孔，试图代表有利的体积膨胀变化，从CCSH沉淀在多孔介质中。在代表典型实验室条件的150°C和1.1 MPa CO2下，该模型预测当假硅灰石CaSiO3多晶型物在升高的pH下反应以产生CaCO3、SiO2（am）和雪硅钙石时，渗透率显著下降。通过加入NaOH提高pH值的效果，增加了CO2的溶解度，增加了CaSiO3的溶解，并支持雪硅钙石过饱和。相反，硅灰石多晶型物的反应导致CaCO3和SiO2（am）形成，具有有限的渗透性影响。硅灰石较低的溶解度和较慢的溶解速率抑制雪硅钙石的形成。在代表深层地下油田条件（40°C和7.5 MPa CO2）的高压下进行的模拟表明，CaSiO3与CO2的反应可以降低渗透率并密封不必要的泄漏路径。
The injection of CO2deep underground, i.e., geologic carbon sequestration, has attracted considerable attention for climate change mitigation. A reliable caprock for secure containment is essential, alongside strategies for sealing flow paths to prevent leaks. In this study, we explore ways in which reactions of CO2with CaSiO3can be used for targeted mineral precipitation and permeability controlin situ. Previous work has suggested that certain CaSiO3polymorphs can produce pore-filling precipitates that successfully inhibit flow, whereas others produce precipitates with little impact. In this work, a one-dimensional reactive transport model was developed for a centimeter-scale system to explore connections between the pore and continuum scale. The model considers four reactions involving CaSiO3, CaCO3, SiO2(am), and the crystalline calcium silicate hydrate (CCSH) tobermorite. A key feature is incorporation of microporosity, with an attempt to represent favorable volume expanding changes from CCSH precipitation in porous media. At 150°C and 1.1 MPa CO2, representing typical laboratory conditions, the model predicts significant permeability drop when reacting the pseudowollastonite CaSiO3polymorph at elevated pH to produce CaCO3, SiO2(am), and tobermorite. The effect of increasing pH via by NaOH addition, which increases CO2solubility, increases CaSiO3dissolution, and supports tobermorite supersaturation. In contrast, reaction of the wollastonite polymorph results in CaCO3and SiO2(am)formation, with limited permeability impact. Wollastonite's lower solubility and slower dissolution rate inhibits tobermorite formation. Simulation at the high pressures representative of deep subsurface field conditions (40°C and 7.5 MPa CO2) suggests that reaction of CaSiO3with CO2could reduce permeability and seal unwanted leakage pathways.