Geoenergy Science and Engineering最新文献

Probabilistic approach for static carbon storage capacity estimation: A case study on the VR014 depleted gas field in offshore Louisiana, USA 静态碳储量估算的概率方法——以美国路易斯安那州近海VR014枯竭气田为例

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-02-10 DOI: 10.1016/j.geoen.2026.214397

Ahmed K. Eleslambouly , Mursal Zeynalli , Emad W. Al-Shalabi , Mohammad Alsuwaidi

Depleted hydrocarbon reservoirs offer a technically viable and cost-effective solution for long-term geological carbon storage (GCS), particularly in offshore settings where infrastructure and subsurface data are well established. This study assesses the CO₂ storage potential of the VR014 Field, a depleted gas reservoir located offshore Louisiana in the Gulf of Mexico, by developing a static petrophysical model reflecting the field's depleted conditions. The workflow integrates 3D geostatistical modeling techniques to characterize five gas-bearing sandstone intervals. Three-dimensional spatial variations of petrophysical parameters were analyzed to assess reservoir heterogeneity and depleted static conditions, to inform volumetric storage estimation using a probabilistic approach. Storage capacity, as determined by a probabilistic Monte Carlo analysis, yields a total CO₂ storage capacity ranging from 56.1 million tonnes (Mt; P90) to 221.6 Mt (P10), with a P50 estimate of 115.4 Mt. The CRISI2 and BIG2_1C intervals account for the largest share of this capacity, driven by their superior reservoir quality, favorable structural positioning, and depleted volumes. Sealing integrity is supported by regionally continuous low-permeability shale units and fault transmissibility analysis, which confirms predominantly sealing behavior. The existing pressure depletion allows a wide operational injection window while maintaining safety margins below fracture thresholds. These findings demonstrate that VR014 Field offers favorable low-risk conditions for secure and efficient CO₂ sequestration. The integrated static modeling framework developed in this study provides a scalable and transferable methodology for the accelerated evaluation of CO₂ storage potential in other depleted gas fields across the Gulf of Mexico, thereby contributing to the advancement of basin-wide screening, site selection, and pre-injection certification strategies for offshore CO₂ storage deployment.

枯竭油气藏为长期地质碳储存（GCS）提供了一种技术上可行且具有成本效益的解决方案，特别是在基础设施和地下数据建立良好的海上环境中。本研究通过建立反映油田枯竭状况的静态岩石物理模型，评估了位于墨西哥湾路易斯安那州近海的VR014气田的二氧化碳储存潜力。该工作流程集成了三维地质统计建模技术，以表征五个含气砂岩层段。分析了岩石物理参数的三维空间变化，以评估储层非均质性和枯竭静态条件，并使用概率方法进行体积存储估算。通过概率蒙特卡罗分析确定的存储容量，产生的总二氧化碳存储容量从5610万吨（Mt; P90）到22160万吨（P10）， P50估计为1154万吨。由于其优越的储层质量，有利的结构位置和枯竭的体积，crisisi2和BIG2_1C层段占该容量的最大份额。区域性连续的低渗透页岩单元和断层传递性分析支持了密封的完整性，证实了主要的密封行为。现有的压力耗尽允许更宽的操作注入窗口，同时保持低于压裂阈值的安全裕度。这些发现表明，VR014油田为安全高效的二氧化碳封存提供了有利的低风险条件。本研究开发的集成静态建模框架为加速评估墨西哥湾其他枯竭气田的二氧化碳储存潜力提供了一种可扩展和可转移的方法，从而有助于推进全盆地范围内的筛选、选址和海上二氧化碳储存部署的预注入认证策略。

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引用次数: 0

Inference of pattern-based geological CO2 sequestration and oil recovery potential in a commingled main pay and residual oil zone CO2-EOR flood 基于模式的主产层与剩余油混合层CO2- eor油藏地质封存与采收率潜力推断

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-02-09 DOI: 10.1016/j.geoen.2026.214414

C. Özgen Karacan, Emil D. Attanasi, Sean T. Brennan, Peter D. Warwick

Several detailed studies have shown that residual oil zones (ROZs) can present significant resources for additional hydrocarbon recovery as well as subsurface carbon dioxide (CO₂) sequestration via enhanced oil recovery by injecting CO₂ (CO₂-EOR). Field development strategies included new wells drilled dedicated to main pay zones (MPZ) and ROZs, or existing wells in MPZs deepened to ROZs for commingled injection-production using different well patterns. The latter presented a challenge when discerning the injection and production from each of the zones, and for subsequent quantification of CO₂ sequestration and EOR potential from different patterns and from the field.

In this paper, an innovative method for analyzing commingled injections and productions from MPZs and ROZs, with application to pattern-based data from four staggered line drive patterns in Wasson Field's Denver Unit, Texas, USA, was developed. Decline curve and ratio-trend methods were used as means of history-matching and forecasting. Cumulative production-time and cumulative production-rate data for oil, gas, and water, as well as water-oil ratio (WOR) and gas-oil ratio (GOR), were analyzed along with injection data for time intervals covering major injection events in MPZ, or MPZ and ROZ combined. A combined analysis enabled inference of allocation of fluids into different zones during WAG (water alternating gas) injection and thereby estimation of CO₂ storage, utilization, and retention in different zones as a function of total injection. Results show that ROZs generally present higher CO₂ sequestration potential compared to MPZs, and a comparable incremental oil recovery factor of ∼20%, on average. Results based on ratio analysis further show that while the WOR trend of the pattern production is mostly dominated and controlled by ROZ, GOR is controlled by both intervals. Although the method relying on decline curves and the approach used in zonal fluid allocations are subject to their limitations, this study presents a practical and innovative well-pattern-based method to infer and forecast CO₂ sequestration and oil recovery quantities and fluid ratios from MPZs and ROZs in commingled operations and highlight the added potential offered by ROZs.

一些详细的研究表明，通过注入二氧化碳（CO2- eor）提高采收率，剩余油区（roz）可以为额外的油气采收率和地下二氧化碳（CO2）封存提供重要的资源。油田开发策略包括在主要产油区（MPZ）和roz上钻新井，或在MPZ上钻现有井至roz，使用不同的井网进行混合注采。后者在识别每个层的注入和产量，以及随后从不同模式和现场量化二氧化碳封存和提高采收率潜力方面提出了挑战。本文开发了一种创新的方法，用于分析mpz和roz的混合注入和产出，并应用于美国德克萨斯州丹佛单元Wasson油田四个交错线驱动模式的模式数据。采用下降曲线法和比值趋势法进行历史匹配和预测。对油、气、水的累积生产时间和累积生产速率数据，以及水油比（WOR）和气油比（GOR），以及MPZ或MPZ和ROZ合并的主要注入事件的时间间隔数据进行了分析。通过综合分析，可以推断出在WAG（水交替气）注入过程中流体在不同层位的分配情况，从而估算出不同层位的CO2储存、利用和滞留情况，并将其作为总注入量的函数。结果表明，与mpz相比，roz通常具有更高的CO2固存潜力，并且平均可增加约20%的原油采收率。基于比值分析的结果进一步表明，模式生成的WOR趋势主要由ROZ主导和控制，而GOR受两个区间的控制。尽管依赖于递减曲线的方法和用于层间流体分配的方法存在局限性，但本研究提出了一种基于井型的实用创新方法，可以从混合作业的mpz和roz推断和预测CO2封存量、采收率和流体比，并突出了roz提供的附加潜力。

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引用次数: 0

Modeling fracture initiation pressure and tortuosity along perforations 模拟裂缝起裂压力和孔眼弯曲度

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-02-09 DOI: 10.1016/j.geoen.2026.214399

Bruno Broesigke Holzberg , Lucas do Nascimento Sagrilo , Romulo Reis Aguiar , Carlos André Bertolini , Francisco Henriques Ferreira

A model to perform a joint analysis of fracture initiation pressure and tortuosity along perforations in arbitrary wells is presented. Existing analytical solutions for fracture initiation analyses along perforations were reviewed and extended to incorporate tortuosity. To verify the representativeness of the solutions, finite element analyses were conducted. Comparisons between analytical and numerical methods revealed that although analytical solutions provide reliable stress estimates along the perforations, they tend to fail when applied to zones close to the perforation edges. To address this limitation in analytical modeling, it is proposed to discard results obtained near the edges and replace them with slightly offset values, where the solution remains valid. The importance of analyzing fracture initiation conditions along the perforation, including tortuosity is also demonstrated. Zones of a perforation with low fracture initiation pressures may exhibit high-tortuosity effects, compromising fracture initiation. This study enhances the understanding of the fracture initiation process and provides analytical solutions that consider both fracture initiation pressure and tortuosity along perforations. These elements can be used to define new criteria for fracture initiation in perforated wellbores, contributing to more effective fracturing jobs.

建立了任意井沿射孔方向的裂缝起裂压力和弯曲度联合分析模型。回顾了现有的沿射孔裂缝起裂分析方法，并将其扩展到弯曲度。为了验证解的代表性，进行了有限元分析。分析方法和数值方法的对比表明，尽管解析解提供了沿射孔的可靠应力估计，但当应用于射孔边缘附近的区域时，它们往往失效。为了解决分析建模中的这一限制，建议丢弃在边缘附近获得的结果，并用稍微偏移的值替换它们，其中解决方案仍然有效。分析沿射孔的裂缝起裂条件（包括弯曲度）的重要性。低起裂压力的射孔区域可能表现出高弯曲效应，从而影响起裂。该研究增强了对裂缝起裂过程的理解，并提供了考虑裂缝起裂压力和射孔弯曲度的分析解决方案。这些元件可用于确定射孔井中起裂的新标准，有助于提高压裂作业的效率。

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引用次数: 0

Low salinity water - engineered microsphere injection for in-depth conformance control in permeable carbonates: an experimental study 低矿化度水工程微球注入用于渗透性碳酸盐岩的深度控制：实验研究

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-02-09 DOI: 10.1016/j.geoen.2026.214419

Dongqing Cao , Subhash Ayirala , Salah Saleh , Ghaida Aljuhani

Low salinity water (LSW) - engineered microsphere injection presents a promising hybrid technique for in-depth conformance control in permeable carbonate reservoirs. However, the process faces significant challenges due to the complex interactions between microspheres and saline brines, especially at high temperature and high salinity conditions. This study investigated the flow and oil recovery performance of this hybrid process within carbonate porous media to elucidate the synergistic effects through coreflooding tests at reservoir temperature 95 °C and pore pressure 3100 psi. Results showed that the migration/blocking performances of microsphere in cores were sensitive to brine salinity particularly at elevated temperature due to weak zeta potential. While microspheres swelled as salinity decreased, those dispersed in conventional high salinity injection water generated much higher differential pressure when injected into brine-saturated carbonate cores than in LSW. Merely mixing microspheres with LSW was insufficient from blocking point of view. Instead, a two-step approach was proposed where microspheres dispersed in conventional injection water (CIW) were first injected, followed by low salinity water injection. Single-phase flow tests demonstrated that this approach produced sufficient blocking in high-permeability carbonate core plugs. The LSW further enhanced blocking and mitigated high retention of microsphere caused by poor dispersibility in high salinity water. Oil displacement test confirmed the blocking capabilities of this method in the presence of oil. The incremental oil recovery by this method reached 8.3% after a bump water flooding that was much higher than LSW alone injection, indicating effective synergistic effects between microspheres and LSW.

低矿化度水（LSW）微球注入技术是一种很有前途的混合技术，可用于渗透碳酸盐岩储层的深度控制。然而，由于微球与盐水之间复杂的相互作用，特别是在高温和高盐度条件下，该工艺面临着重大挑战。本研究通过在储层温度95°C、孔隙压力3100 psi条件下的岩心驱油试验，研究了碳酸盐多孔介质中该混合过程的流动和采收率，以阐明协同效应。结果表明，岩心中微球的运移/封堵性能对盐水盐度敏感，特别是在温度升高时，由于zeta电位较弱。当微球随着矿化度的降低而膨胀时，那些分散在常规高矿化度注入水中的微球在注入饱和盐水的碳酸盐岩心时产生的压差要比LSW高得多。从阻挡的角度来看，仅仅将微球与LSW混合是不够的。相反，提出了一种两步法，首先注入分散在常规注入水中的微球，然后注入低矿化度的水。单相流测试表明，这种方法在高渗透率碳酸盐岩心桥塞中产生了足够的封堵效果。LSW进一步增强了堵塞，减轻了微球在高盐度水中由于分散性差而造成的高滞留。驱油试验证实了该方法在有油情况下的封堵能力。该方法经凸水驱后的原油增量采收率达到8.3%，远高于单独注入LSW，表明微球与LSW之间存在有效的协同效应。

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引用次数: 0

Pillar safety analysis and layout optimization for hydrogen storage cavern groups in bedded salt formations — A study based on thermal-hydraulic-mechanical (THM) coupling 层状盐层储氢洞穴群矿柱安全性分析及布局优化——基于热-液-力耦合的研究

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-02-09 DOI: 10.1016/j.geoen.2026.214417

Xiao Wang , Guimin Zhang , Jingjiang Li , Mingnan Xu , Yashuai Huang , Yuxuan Liu , Si Huang , Long Chen , Yang Hong , Xiaoyi Liu , Xilin Shi , Yinping Li

Salt cavern hydrogen storage is regarded as a significant development direction for large-scale hydrogen energy storage. Compared to other stored gases such as natural gas or compressed air, hydrogen exhibits characteristics such as smaller molecular size, lower dynamic viscosity, and higher chemical reactivity, which could potentially impact the stability of surrounding rock, particularly cavern pillars, through seepage. Furthermore, the high-frequency and high-intensity injection-withdrawal cycles of hydrogen result in greater thermal disturbances to the storage cavern compared with natural gas. Accordingly, a thermo–hydro–mechanical (THM) coupling model is developed to quantitatively elucidate the magnitude and spatial extent of the effects of hydrogen seepage, injection–withdrawal–induced temperature fluctuations, and surrounding rock stress on the safety of cavern group pillars. Additionally, based on these findings, the layout scheme of the hydrogen storage cavern group was optimized. The main conclusions drawn are as follows: Hydrogen seepage has a non-negligible influence on cavern pillars, leading to a reduction in the strength of surrounding rocks, particularly interlayers; although the thermal disturbance from hydrogen injection-withdrawal cycles causes temperature redistribution within surrounding rock, its impact range is limited, posing no significant threat to pillar safety; the hard interlayers represent the main damaged zones within cavern pillars, and seepage further reduces their strength, thus these interlayers require special attention in engineering practice; under the condition of equal resource utilization for a single salt cavern, adopting a parallelogram layout results in improved pillar stability within the hydrogen storage cavern group. The results from this research can provide a useful reference for large-scale hydrogen energy storage.

盐穴储氢被认为是大规模储氢的重要发展方向。与天然气或压缩空气等其他储存气体相比，氢气具有分子尺寸更小、动态粘度更低、化学反应性更高的特点，这可能会通过渗透影响围岩的稳定性，尤其是洞穴柱的稳定性。此外，与天然气相比，氢气的高频和高强度注入-提取循环对储洞的热扰动更大。在此基础上，建立了热-水-力耦合模型，定量分析了氢渗流、注回采温度波动和围岩应力对洞室群矿柱安全的影响程度和空间范围。并在此基础上对储氢洞室组的布置方案进行了优化。主要结论如下：氢渗流对洞室矿柱有不可忽视的影响，导致围岩特别是夹层强度降低；注回采氢循环产生的热扰动虽然引起围岩内部温度重分布，但其影响范围有限，对矿柱安全不构成显著威胁；硬夹层是洞室柱内部的主要破坏区域，渗流会进一步降低其强度，因此在工程实践中需要特别注意；在单个盐洞资源利用均等的情况下，采用平行四边形布局可以提高储氢洞群内矿柱的稳定性。研究结果可为大规模储氢提供有益的参考。

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引用次数: 0

Seawater-based surfactant formulation for supercritical CO2 injection into coastal saline aquifers: Implications for fresh-water conversion and carbon management 海水基表面活性剂配方用于向沿海咸水层注入超临界二氧化碳：对淡水转化和碳管理的影响

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-02-08 DOI: 10.1016/j.geoen.2026.214416

Seokgu Gang , Joo Yong Lee , Shuang Cindy Cao , Jeonghwan Lee , Jae-Eun Ryou , Jongwon Jung

Coastal saline aquifers exhibit salinity levels comparable to seawater due to the intrusion of seawater. To effectively utilize the storage potential of aquifers, researchers have investigated the enhancement of carbon dioxide injection performance through the use of chemical additives such as polymers, surfactants, and nanofluids. In field applications, a significant amount of freshwater is typically required to prepare aqueous solutions containing these chemical additives. However, the use of salt-free freshwater necessitates additional transportation infrastructure and procurement costs, which in turn increases the overall cost of subsurface storage. In light of this, the present study evaluates the feasibility of utilizing seawater—which is more readily available than freshwater—for the offshore preparation of chemical additive solutions. For this evaluation, a surfactant known to be effective under deionized water conditions was introduced into a NaCl solution with a concentration similar to that of seawater. The interfacial characteristics between supercritical carbon dioxide and the aqueous solution, along with the injection efficiency in a porous medium, were subsequently assessed. The results indicate that the presence of NaCl induces salt screening and salting-out effects, leading to a further reduction in interfacial tension compared to that in pure water. While the contact angle exhibits only minor variations compared to interfacial tension, the capillary factor—defined as the product of interfacial tension and the cosine value of the contact angle—is predominantly influenced by the interfacial tension. Nonetheless, within the range of conditions and surfactant formulations tested in this study, the reduction in the capillary factor driven by interfacial tension did not lead to any measurable additional increase in injection efficiency. These results indicate that, for the present system, seawater-based surfactant solutions with added NaCl can achieve injection efficiencies comparable to those prepared with freshwater, suggesting that seawater is a promising substitute in practical applications. However, the extent to which this behavior holds in other reservoir conditions and for different surfactant systems should be examined in future studies.

由于海水的侵入，沿海含盐含水层显示出与海水相当的盐度水平。为了有效地利用含水层的储存潜力，研究人员研究了通过使用聚合物、表面活性剂和纳米流体等化学添加剂来增强二氧化碳注入性能的方法。在现场应用中，通常需要大量的淡水来制备含有这些化学添加剂的水溶液。然而，使用无盐淡水需要额外的运输基础设施和采购成本，这反过来又增加了地下储存的总成本。鉴于此，本研究评估了利用比淡水更容易获得的海水用于近海制备化学添加剂溶液的可行性。为了进行评估，将一种已知在去离子水条件下有效的表面活性剂引入浓度与海水相似的NaCl溶液中。随后，对超临界二氧化碳与水溶液之间的界面特性以及多孔介质中的注入效率进行了评估。结果表明，NaCl的存在诱导了盐筛选和盐析作用，导致界面张力比纯水中进一步降低。与界面张力相比，接触角仅表现出微小的变化，而毛细管因子（定义为界面张力和接触角余弦值的乘积）主要受界面张力的影响。然而，在本研究测试的条件和表面活性剂配方范围内，由界面张力驱动的毛细血管因子的降低并没有导致任何可测量的注入效率的额外增加。这些结果表明，对于目前的体系，添加NaCl的海水基表面活性剂溶液可以达到与淡水制备的同等的注入效率，这表明海水在实际应用中是一种很有前景的替代品。然而，在其他储层条件和不同表面活性剂体系中，这种行为的适用程度应该在未来的研究中进行检验。

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引用次数: 0

Coupled thermal-hydrodynamic-chemical modeling of calcite scaling in geothermal wells 地热井中方解石结垢的热-水动力-化学耦合模拟

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-02-08 DOI: 10.1016/j.geoen.2026.214415

Mojtaba Ghaedi , Raoof Gholami , Spyros Bellas , Emmanuel Stamatakis

Calcite scaling is a common and persistent issue in geothermal reservoirs, leading to flow restrictions, reduced operational efficiency, increased maintenance costs, and, in severe cases, system failure. Accurate prediction of the location, thickness, and temporal evolution of calcite scale is, therefore, essential for effective management and treatment planning of geothermal wells. This study presents a coupled thermal-hydrodynamic-chemical modeling framework to simulate calcite scaling in geothermal systems. An iterative drift-flux model was employed to resolve the temperature and pressure profiles along the wellbore, while the geochemical interactions driving calcite precipitation were modeled using PHREEQC. The simulation incorporates both crystallization and particulate scaling mechanisms, as well as the potential for scale removal from the wellbore walls. Model validation against field data from wells SNLG87-29 (Nevada, USA) and RN-15 (Reykjanes, Iceland) demonstrated strong agreement in temperature and pressure profiles. Furthermore, solubility models for calcite and CO₂ were calibrated against existing experimental data. The modeling approach accurately captured the evolution of calcite scaling in well 84-7 (Dixie Valley, USA), predicting a maximum scale thickness of approximately 30 mm and a vertical distribution span of around 290 m after 75 days of operation. It also appeared that in well 84-7, a 25% increase in calcium concentration led to a 50% reduction in flow area within only 56 days, compared to 74 days in the case with the original calcium concentration. These results underscore the ability of the proposed modeling approach as an important tool for predicting and managing calcite scaling, thereby enhancing the sustainability of geothermal energy production.

方解石结垢是地热储层中一个常见且持续存在的问题，它会导致流动受限、操作效率降低、维护成本增加，严重时还会导致系统故障。因此，准确预测地热井方解石垢的位置、厚度和时间演化对地热井的有效管理和治理规划至关重要。本研究提出了一个热-水动力-化学耦合模型框架来模拟地热系统中的方解石结垢。采用迭代漂移通量模型求解沿井筒的温度和压力剖面，同时使用PHREEQC模拟驱动方解石沉淀的地球化学相互作用。该模拟结合了结晶和颗粒结垢机制，以及从井筒壁上去除结垢的可能性。根据SNLG87-29井（美国内华达州）和RN-15井（冰岛Reykjanes）的现场数据进行的模型验证表明，温度和压力剖面非常吻合。此外，根据现有实验数据对方解石和CO2的溶解度模型进行了校准。该建模方法准确捕获了84-7井（美国Dixie Valley）方解石结垢的演化过程，在75天的作业后，预测最大结垢厚度约为30 mm，垂直分布跨度约为290 m。此外，在84-7井中，钙浓度增加25%，在56天内导致流动面积减少50%，而在钙浓度不变的情况下，流动面积减少了74天。这些结果强调了所提出的建模方法作为预测和管理方解石结垢的重要工具的能力，从而提高地热能源生产的可持续性。

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引用次数: 0

Decision making on salt precipitation risk in geologic carbon storage: Driving factors and uncertainties 地质碳库盐降水风险决策：驱动因素与不确定性

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-02-05 DOI: 10.1016/j.geoen.2026.214411

Hakan Alkan , Nematollah Zamani , Oleksandr Burachok , Dirk Baganz , Mohd Amro

Salt precipitation during geologic carbon storage (GCS) can significantly impact injectivity, both positively and negatively, making accurate prediction of this phenomenon critically important. Injected CO₂—owing to its strong evaporation potential—displaces and evaporates in-situ brine in a process known as drying-out (DO). Once the salt solubility limit is exceeded, salt begins to precipitate (salting-out, SO), potentially leading to substantial permeability reduction and, in extreme cases, complete pore blockage.

In this study, we aim to advance the understanding of DO and SO dynamics by integrating insights from our ongoing research with a critical review of existing literature. Our goal is to develop a comprehensive workflow to assess the extent, distribution, and controlling factors of SO, along with its feedback mechanisms and mitigation strategies relevant for engineering practice. We first revisit the fundamental physics of DO and SO in the context of GCS, identifying key drivers and thresholds. Subsequently, we evaluate how geological, reservoir, and operational parameters influence these processes and their implications for storage performance. We further synthesize current uncertainties derived from laboratory experiments and numerical modeling approaches. The study concludes with a ranking of the relevancy of the driving factors and their associated uncertainty levels, supporting the design of sustainable and efficient CO₂ injection strategies. Rather than focusing solely on technical complexities, this work aims to provide reservoir and production engineers with a practical, decision-oriented workflow that also includes proposed methods for mitigating the risk of salt precipitation in GCS operations.

地质储碳（GCS）过程中的盐降水对注入能力有显著的正向和负向影响，因此对这一现象的准确预测至关重要。注入的二氧化碳-由于其强大的蒸发潜力-在称为干干（DO）的过程中取代并蒸发了原位盐水。一旦盐的溶解度超过极限，盐就开始沉淀（盐析），可能导致渗透率大幅降低，在极端情况下，完全堵塞孔隙。在这项研究中，我们的目标是通过将我们正在进行的研究的见解与现有文献的批判性回顾相结合，来推进对DO和SO动力学的理解。我们的目标是开发一个全面的工作流程来评估SO的范围、分布和控制因素，以及与工程实践相关的反馈机制和缓解策略。我们首先在GCS的背景下回顾了DO和SO的基本物理，确定了关键驱动因素和阈值。随后，我们评估了地质、油藏和操作参数如何影响这些过程及其对存储性能的影响。我们进一步综合了来自实验室实验和数值模拟方法的当前不确定性。该研究总结了驱动因素的相关性及其相关不确定性水平，为设计可持续和高效的二氧化碳注入策略提供了支持。这项工作的目的不是仅仅关注技术复杂性，而是为油藏和生产工程师提供一个实用的、以决策为导向的工作流程，其中还包括降低GCS作业中盐沉淀风险的建议方法。

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引用次数: 0

A convection-free optical method for measuring CO2 diffusion in porous media 一种测量多孔介质中CO2扩散的无对流光学方法

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-02-04 DOI: 10.1016/j.geoen.2026.214395

Enoc Basilio, Simon Zougheib, Mouadh Addassi, Mohammed Al-Juaied, Tadd Truscott, Hussein Hoteit

Carbon sequestration in saline aquifers is a promising strategy to mitigate anthropogenic carbon dioxide (CO₂) emissions. This study presents a novel experimental methodology to quantify CO₂ mass diffusion in porous media by employing a transmitted-light visualization technique. Unlike conventional approaches, our method isolates pure molecular diffusion by positioning the capillary tubes vertically with their open ends facing downward. In this inverted configuration, denser CO₂-enriched fluid is introduced from the bottom, naturally suppressing buoyancy-driven convection and ensuring that mass transfer occurs solely through diffusion. These transparent tubes, packed with glass beads of defined grain-size distributions and saturated with a pH-sensitive indicator solution, allow for real-time visualization and quantification of CO₂ dissolution. The acidification from dissolved CO₂ causes a color transition in the indicator, which is recorded and analyzed to extract effective diffusion coefficients. This setup enables direct observation of CO₂ transport in porous media under controlled, convection-free conditions. Systematic experiments examining the effects of salinity and pore structure reveal that increased salinity and reduced grain size significantly decrease CO₂ diffusivity. This work offers a simple method for convection-free quantification of CO₂ diffusivity in brine-saturated porous media, enabling more accurate modeling of solubility trapping and improving predictions of long-term CO₂ transport and retention in saline aquifers.

在含盐含水层中固碳是一种很有前景的减少人为二氧化碳排放的策略。本研究提出了一种新的实验方法，利用透射光可视化技术来量化多孔介质中二氧化碳的质量扩散。与传统方法不同，我们的方法通过垂直定位毛细管，其开放端朝下来分离纯分子扩散。在这种倒置的结构中，密度更大的富含二氧化碳的流体从底部引入，自然地抑制浮力驱动的对流，并确保仅通过扩散进行传质。这些透明的管，挤满了确定粒度分布的玻璃珠，并饱和了ph敏感的指示剂溶液，可以实时可视化和量化二氧化碳的溶解。溶解二氧化碳的酸化会导致指示剂出现颜色转变，记录并分析这一变化，以提取有效扩散系数。该装置可以在可控的无对流条件下直接观察多孔介质中的CO2传输。系统的实验研究了盐度和孔隙结构的影响，发现盐度的增加和颗粒尺寸的减小显著降低了CO2的扩散系数。这项工作提供了一种简单的方法，可以对盐水饱和多孔介质中二氧化碳的扩散系数进行无对流量化，从而更准确地模拟溶解度捕获，并改进对盐水含水层中二氧化碳长期运输和保留的预测。

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引用次数: 0

Permeability evolution and heat transfer in hot sedimentary aquifers and enhanced geothermal systems: Insights from coupled DFN-THM modeling 热沉积含水层和增强型地热系统的渗透率演化和传热：来自耦合ddn - thm模型的见解

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-02-04 DOI: 10.1016/j.geoen.2026.214387

Yueqiang Ma , Ying Li , Quan Gan

Hot Sedimentary Aquifers (HSA) and Enhanced Geothermal Systems (EGS) represent two important geothermal resources with distinct geological and mechanical characteristics. Understanding their permeability evolution and heat transfer behavior is critical for assessing reservoir performance and guiding engineering design. In this study, a discrete fracture network (DFN) model coupled with thermo-hydro-mechanical (THM) processes is developed to investigate the contrasting response of HSA and EGS under varying stress states, pore pressures, fracture densities, reservoir temperatures, and intrinsic permeabilities. The results show that fracture aperture evolution is initially dominated by normal closure, whereas shear dilation becomes significant once stresses reach the Coulomb failure criterion. Compared to EGS, the higher fracture density in HSA leads to larger cumulative apertures and higher heat extraction efficiency. Quantitative analysis indicates that fracture density strongly controls thermal propagation, with a critical range where heat transfer efficiency increases rapidly. Reservoir temperature and permeability further regulate fracture sensitivity, with EGS showing greater stress- and temperature-dependent variability than HSA. These findings highlight the fundamental differences in fluid–heat–mechanical coupling between HSA and EGS. The insights gained provide practical implications for geothermal energy development, including optimizing well placement, fracture stimulation strategies, and reservoir management to enhance long-term sustainability.

热沉积含水层（HSA）和增强型地热系统（EGS）是两种重要的地热资源，具有不同的地质和力学特征。了解储层的渗透率演化和传热行为对评价储层动态和指导工程设计具有重要意义。在这项研究中，建立了一个离散裂缝网络（DFN）模型，结合热-水-力学（THM）过程，研究了不同应力状态、孔隙压力、裂缝密度、储层温度和固有渗透率下HSA和EGS的对比响应。结果表明：裂缝孔径演化初期以法向闭合为主，当应力达到库仑破坏准则时，剪切扩张开始显著；与EGS相比，HSA中较高的裂缝密度导致了更大的累积孔径和更高的排热效率。定量分析表明，断口密度对热传导有很强的控制作用，存在一个传热效率迅速提高的临界范围。储层温度和渗透率进一步调节裂缝敏感性，EGS比HSA表现出更大的应力和温度依赖性。这些发现突出了HSA和EGS在流体-热-机械耦合方面的根本差异。所获得的见解为地热能源开发提供了实际意义，包括优化井位、压裂增产策略和油藏管理，以提高长期可持续性。

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引用次数: 0