Geoenergy Science and Engineering最新文献_第7页

Rheological behavior of ultra-high temperature cement slurries across a wide range of temperatures from 30°C to 220°C 超高温水泥浆在30 ~ 220℃范围内的流变性能

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-03-01 Epub Date: 2025-12-11 DOI: 10.1016/j.geoen.2025.214340

Xiujian Xia , Han Ge , Renzhou Meng , Jiapei Du , Ye Qian , Xueyu Pang , Pengpeng Li , Haipe Wang

This study aims to investigate the influences of temperature and critical additives (suspension aid and dispersant) on the rheological performances of oil well cement slurries. A high-temperature and high-pressure rheometer was used to evaluate the rheology of high-temperature cement slurries at eight different temperatures (30 °C, 60 °C, 90 °C, 120 °C, 150 °C, 180 °C, 210 °C and 220 °C) using multiple “ramp and hold” testing schemes. Test results reveal that almost all slurries exhibit thermal thinning and shear thinning behavior and that the shear thinning effect is enhanced at high temperatures. However, increases in slurry viscosity with increasing temperature at certain temperature ranges are also observed, typically at relatively low shear rates (<100 s⁻¹), which can be attributed to both structural changes of polymer additives and cement hydration reactions. Apparent viscosity of cement slurries generally increases with increasing dosage of suspension aid and decrease with increasing dosage of dispersant. It is found that all the seven rheological models investigated in this study fit well with the experimental results at temperatures between 30 °C and 120 °C, but the fitting quality deteriorates at higher temperatures, especially for the two-parameter models (such as the Bingham-plastic and Power-law models). The three-parameter Hershel-Bulkley (H-B) model is observed to provide the best fitting quality to experimental data at all temperatures. The variations of all three H-B model parameters as functions of temperature can be divided into two stages (30 °C–120 °C and 150 °C–220 °C) due to increases in slurry viscosity at approximately 150 °C and each stage can be fitted reasonably well with a quadratic equation. The yield stress obtained by the H-B model typically show an increasing trend with increasing temperature and increasing dosage of suspension aid. The rheology test results of water solutions of pure suspension aid and dispersant exhibit apparent different behaviors compared to that of cement slurries, which can be attributed to the influences of cement hydration as well as its interactions with cement additives.

研究温度和关键添加剂（助悬剂和分散剂）对油井水泥浆流变性能的影响。采用高温高压流变仪对高温水泥浆在8种不同温度（30°C、60°C、90°C、120°C、150°C、180°C、210°C和220°C）下的流变性进行了评估，并采用了多个“斜坡和保持”测试方案。试验结果表明，几乎所有浆料均表现出热减薄和剪切减薄的特性，且高温下剪切减薄效果增强。然而，在一定温度范围内，通常在相对较低的剪切速率下（<100 s−1），浆料粘度随温度升高而增加，这可归因于聚合物添加剂的结构变化和水泥水化反应。水泥浆的表观粘度一般随助悬剂用量的增加而增大，随分散剂用量的增加而减小。研究发现，在30 ~ 120℃温度范围内，7种流变模型均与实验结果拟合良好，但温度越高，拟合质量越差，尤其是双参数模型（如Bingham-plastic模型和Power-law模型）。在所有温度下，三参数hershell - bulkley （H-B）模型对实验数据的拟合质量最好。所有三个H-B模型参数作为温度函数的变化可以分为两个阶段（30°C - 120°C和150°C - 220°C），因为浆料粘度在大约150°C时增加，每个阶段都可以用二次方程很好地拟合。H-B模型得到的屈服应力随温度的升高和助悬剂用量的增加而增大。纯悬浮剂和分散剂水溶液的流变性能试验结果与水泥浆表现出明显的不同，这主要是由于水泥水化的影响以及与水泥外加剂的相互作用。

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引用次数: 0

Corrigendum to “ManyWells: Simulation of multiphase flow in thousands of wells” [Geoenergy Sci. Eng. 257 (2026) 214226] “多井：在数千口井中模拟多相流”的勘误[地球能源科学]。Eng. 257 (2026) 214226]

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-03-01 Epub Date: 2025-12-16 DOI: 10.1016/j.geoen.2025.214344

Bjarne Grimstad , Erlend Lundby , Henrik Andersson

引用次数: 0

Optimal sequential decision-making in geosteering: A reinforcement learning approach 地质导向中的最优顺序决策：一种强化学习方法

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-03-01 Epub Date: 2025-12-05 DOI: 10.1016/j.geoen.2025.214304

Ressi Bonti Muhammad , Sergey Alyaev , Reidar Brumer Bratvold

Trajectory adjustment decisions throughout the drilling process, called geosteering, affect subsequent choices and information gathering, thus resulting in a coupled sequential decision problem. Previous works on applying decision optimization methods in geosteering rely on greedy optimization or approximate dynamic programming (ADP). Either decision optimization method requires explicit uncertainty and objective function models, making development of decision optimization methods for complex and realistic geosteering environments challenging to impossible. This study uses the Deep Q-Network (DQN) method, a model-free reinforcement learning (RL) method that learns directly from the decision environment, to optimize geosteering decisions. The expensive computations for RL are handled during the offline training stage. Evaluating DQN needed for real-time decision support takes milliseconds and is faster than the traditional alternatives. Moreover, for two previously published synthetic geosteering scenarios, our results show that RL achieves high-quality outcomes comparable to the quasi-optimal ADP. Yet, the model-free nature of RL means that by replacing the training environment, we can extend it to problems where the solution to ADP is prohibitively expensive to compute. This flexibility will allow its application to more complex environments and enable hybrid versions trained with real data in the future.

在整个钻井过程中，轨迹调整决策（称为地质导向）会影响后续选择和信息收集，从而导致耦合顺序决策问题。以往在地质导向中应用决策优化方法的工作依赖于贪婪优化或近似动态规划。任何一种决策优化方法都需要明确的不确定性和目标函数模型，这使得复杂和现实地质导向环境的决策优化方法的开发具有挑战性甚至不可能。本研究使用Deep Q-Network （DQN）方法，这是一种直接从决策环境中学习的无模型强化学习（RL）方法，以优化地质导向决策。在离线训练阶段处理RL中昂贵的计算。评估实时决策支持所需的DQN只需几毫秒，比传统的替代方案更快。此外，对于之前发表的两种合成地质导向场景，我们的研究结果表明，RL获得了与准最优ADP相当的高质量结果。然而，强化学习的无模型特性意味着，通过替换训练环境，我们可以将其扩展到ADP解决方案计算成本过高的问题。这种灵活性将允许其应用于更复杂的环境，并在未来使用真实数据进行混合版本的训练。

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引用次数: 0

Study on the migration behavior of temporary plugging agents in a wedge-shaped fracture of deep high-temperature rock based on the DDPM multiphase flow model 基于DDPM多相流模型的深部高温岩石楔形裂缝暂堵剂运移行为研究

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-03-01 Epub Date: 2025-12-22 DOI: 10.1016/j.geoen.2025.214351

Yue Wu , Xiongfei Liu , Daobing Wang , Fujian Zhou , Bo Yu

China possesses abundant deep oil and gas resources; however, their exploitation is constrained by high-temperature, high-pressure conditions and the limitations of conventional hydraulic fracturing in creating complex fracture networks. Temporary Plugging and Diverting Fracturing (TPDF), which induces fracture diversion and generates multiple new fractures, represents a promising technology for the development of deep reservoirs. In TPDF, the migration of temporary plugging agents into fractures to form effective blockages and elevate fracture net pressure is critical. Understanding their migration behavior in deep, high-temperature rock fractures is therefore essential. Numerical simulation provides a valuable means for investigating this migration process. However, fracture models are often simplified as rectangles, and most numerical approaches rely on Discrete Element Models (DEM), which are computationally complex and time-intensive. In this study, a multiphase flow mathematical model for temporary plugging agent migration in deep wedge-shaped rock fractures is developed based on the Dense Discrete Phase Model (DDPM). The model is employed to numerically examine the effects of key parameters—including mass concentration of plugging agents, injection rate, carrying liquid viscosity, and wall temperature—on migration behavior under high-temperature conditions. The results show that the sensitivity of these parameters to migration behavior, from highest to lowest, follows the order: injection rate > carrying liquid viscosity > mass concentration > wall temperature. Increases in mass concentration and wall temperature maintain a triangular migration pattern, whereas increases in injection rate and carrying liquid viscosity alter the pattern from triangular to quadrilateral. Raising injection rate or carrying liquid viscosity individually shifts the dominant mechanism from sedimentation to collision and migration. A critical mass concentration of 6 % is identified, beyond which further increases exert minimal influence on subsequent fracture sealing. For TPDF operations in deep reservoirs, factors such as reservoir rock properties and pumping procedures should guide the selection of carrying liquid viscosity and injection rate. As formation temperature increases, the likelihood of plugging agent sedimentation rises due to reduced carrying liquid viscosity. Moreover, the agents experience lower heat exchange than the carrying liquid, resulting in a slower temperature rise for the agents compared with the fluid.

中国拥有丰富的深层油气资源；然而，它们的开发受到高温、高压条件的限制，以及常规水力压裂在形成复杂裂缝网络方面的局限性。临时堵转压裂（TPDF）技术是一种很有前途的深部油藏开发技术，它可以诱导裂缝转向并产生多条新裂缝。在TPDF中，将临时堵剂迁移到裂缝中以形成有效堵塞并提高裂缝净压力至关重要。因此，了解它们在深部高温岩石裂缝中的运移行为至关重要。数值模拟为研究这一迁移过程提供了有价值的手段。然而，裂缝模型通常被简化为矩形，并且大多数数值方法依赖于离散单元模型（DEM），这是计算复杂且耗时的。基于致密离散相模型（DDPM），建立了深部楔形岩石裂缝中暂堵剂运移的多相流数学模型。该模型用于在高温条件下对关键参数（包括堵剂质量浓度、注入速率、载液粘度和壁温）对运移行为的影响进行数值研究。结果表明：各参数对运移行为的敏感性由高到低依次为：注入速率>；载液粘度>；质量浓度>；壁温。质量浓度和壁面温度的增加维持三角形迁移模式，而注入速度和携带液体粘度的增加使三角形迁移模式变为四边形迁移模式。提高注入速度或携带液体粘度分别将主要机制从沉积转变为碰撞和运移。确定了6%的临界质量浓度，超过该浓度，进一步增加对后续裂缝密封的影响最小。对于深部储层的TPDF作业，应根据储层岩石性质和泵送方式等因素来指导携油粘度和注入速率的选择。随着地层温度的升高，由于携带液粘度的降低，堵剂沉积的可能性增加。此外，与携带液体相比，药剂的热交换更低，导致药剂的温度上升速度比流体慢。

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引用次数: 0

Research on the rock-breaking performance of laser-assisted PDC cutters in granite formation 激光辅助PDC切削齿在花岗岩地层中的破岩性能研究

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-03-01 Epub Date: 2025-12-10 DOI: 10.1016/j.geoen.2025.214317

Yachao Ma , Long Li , Wenyuan Zhang , Wenling Zhang , Zhun Rong , Yang Liu , Xiaofeng Xie

Laser-assisted mechanical rock fragmentation technology represents a cutting-edge advancement in the drilling sector. However, its efficiency has fallen short of expectations due to the absence of coordinated laser-cutter deployment methodologies. This study integrates experimental and simulation approaches to establish a laser-PDC cutter granite fragmentation model. Through comparative analysis of double-cylindrical, triple-cylindrical, and cone-hybrid hybrid configurations, the cone-hybrid hybrid configuration emerges as the optimal solution for laser-assisted granite fragmentation. With optimized parameters—20° back rake angle, 6 mm cutter spacing, 9 mm Difference in Depth of Cut, and 0° side rake angle—this configuration achieves peak performance: its comprehensive specific fragmentation energy decreases by 70.81 % compared to the minimum mechanical baseline and by 7.4 % versus laser-assisted triple-cylindrical cutters, significantly enhancing drilling efficiency. The research provides direct theoretical foundations for optimizing laser-PDC bit design in hard formations (e.g., granite) for oil and gas drilling, with further applicability in other challenging rock fragmentation scenarios such as geothermal drilling and deep mining.

激光辅助机械破岩技术是钻井领域的一项前沿技术。然而，由于缺乏协调的激光切割机部署方法，其效率低于预期。本研究将实验与仿真相结合，建立了激光- pdc切割机花岗岩破碎模型。通过对双柱、三柱和锥-杂化混合构型的对比分析，锥-杂化混合构型是激光辅助花岗岩破碎的最优方案。优化后的参数为20°后倾角、6 mm切削齿间距、9 mm切削深度差和0°侧倾角，该配置达到了最佳性能：与最小机械基准相比，其综合比破碎能降低70.81%，与激光辅助的三圆柱切削齿相比降低7.4%，显著提高了钻井效率。该研究为在硬地层（如花岗岩）中优化激光pdc钻头设计提供了直接的理论基础，并进一步适用于地热钻井和深部开采等其他具有挑战性的岩石破碎场景。

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引用次数: 0

Impact of local aperture reduction characteristics on nonlinear flow behavior in rough fractures 局部孔径缩小特性对粗糙裂缝非线性流动特性的影响

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-03-01 Epub Date: 2025-12-05 DOI: 10.1016/j.geoen.2025.214306

Decheng Li , Yu Wu , Yang Hao , Junting Liu , Jichen Shang

The roughness characteristics of rock fractures have been extensively studied. However, the local geometric features of fractures are often overlooked in both experimental and simulation studies and have rarely been thoroughly explored. In this paper, we performed numerical simulations of fluid flow in rough rock fractures to investigate the effects of local aperture reduction (extent (

Δ e

) and quantity (

M

)) on nonlinear flow behavior. The results show that as the

Δ e

and

M

increased, the fracture exhibited stronger nonlinearity and a lower critical

R e

, primarily due to the generation and development of recirculation zones induced by the local aperture reduction. Downstream of these reductions, the fracture walls expanded abruptly, forming complex multi-eddy systems and inducing fluid-wall collisions due to strong inertial forces. These interactions further exacerbated the heterogeneity of both the velocity and pressure fields within the fracture, increasing flow nonlinearity. Additionally, increasing

Δ e

and

M

gradually enlarged the recirculation zones, narrowed the effective flow path, and reduced the fracture's flow performance, as indicated by a decrease in hydraulic aperture. An integrated analysis of the recirculation zone ratio, hydraulic aperture–Re correlations, and energy dissipation distributions reveals that the development of the recirculation zone and increased viscous dissipation are the primary mechanisms underlying flow nonlinearity enhancement induced by local aperture reduction. This study provides new insights into the complexity of fracture flow and the influence of fracture geometry on fluid behavior, advancing the understanding of the relationship between local fracture geometry and fluid flow.

岩石裂缝的粗糙度特征已被广泛研究。然而，裂缝的局部几何特征在实验和模拟研究中往往被忽视，并且很少被深入探讨。本文采用数值模拟方法对粗糙岩石裂隙中的流体流动进行了研究，探讨了局部孔径缩小（程度（Δe）和数量(M)）对非线性流动行为的影响。结果表明：随着Δe和M的增大，裂缝的非线性增强，临界Re降低，这主要是由于局部孔径减小导致再循环带的产生和发展。在这些减少的下游，裂缝壁突然膨胀，形成复杂的多涡系统，并由于强大的惯性力引起流体壁碰撞。这些相互作用进一步加剧了裂缝内速度场和压力场的不均匀性，增加了流动的非线性。随着Δe和M的增大，再循环区域逐渐扩大，有效流道逐渐变窄，裂缝的流动性能逐渐降低，表现为水力孔径的减小。综合分析再循环区比、水力孔径- re相关性和能量耗散分布，发现再循环区的发展和粘性耗散的增加是局部孔径减小导致流动非线性增强的主要机制。该研究为裂缝流动的复杂性和裂缝几何形状对流体行为的影响提供了新的见解，促进了对局部裂缝几何形状与流体流动关系的理解。

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引用次数: 0

Technological approaches to overcoming geothermal well integrity challenges: A review of modern solutions 克服地热井完整性挑战的技术途径：现代解决方案综述

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-03-01 Epub Date: 2025-12-05 DOI: 10.1016/j.geoen.2025.214308

Mohammad Fathy , Foojan Kazemzadeh Haghighi , Graeme Beardsmore , Abdollatif Gharibi

Geothermal energy is a unique and sustainable renewable resource, distinguished by its substantial reserves, extensive geographical distribution, low-carbon characteristics, and robust stability. The wellbore plays a critical role in geothermal energy production, operating in high-temperature and corrosive environments. However, wellbores often face well integrity (WI) challenges during their lifespans, resulting in financial losses, occupational injuries, and environmental harm. To address these challenges, technological approaches can be utilized to enhance WI, develop preventative and mitigative measures, and improve the overall effectiveness of WI management systems. This literature review explores modern solutions, including advanced inspection technologies, nanotechnology, machine learning (ML), and the Internet of Things (IoT), focusing on their applications to ensure the structural integrity of wells. Advanced inspection technologies, leveraging unmanned vehicles and robotic systems, can optimize accessibility to equipment in unreachable areas, minimize human exposure to hazardous environments, and provide real-time data to assist in detecting equipment cracks and leakages. Nanotechnology, such as nano-sensors housed on casings, can remotely observe cement properties, a critical component of WI, effectively enabling early defect detection. Moreover, nanomaterials implemented in wellbore's equipment can strengthen the durability under heavy loads and high temperatures. After the data gathering phase from all available sources, IoT setups, such as the digital twin version of the wellbore, can provide valuable insights into the future phases of the well. By adjusting parameters based on ML predictive results, these setups enable the initiation of effective response plans, enhancing occupational safety and situational awareness.

地热能是一种独特的、可持续的可再生能源，具有储量丰富、地理分布广泛、低碳、稳定性强等特点。在高温和腐蚀性环境中，井筒在地热能源生产中起着至关重要的作用。然而，井筒在其使用寿命期间经常面临井完整性（WI）的挑战，导致经济损失、职业伤害和环境危害。为了应对这些挑战，可以利用技术方法来加强WI，制定预防和缓解措施，并提高WI管理系统的整体有效性。这篇文献综述探讨了现代解决方案，包括先进的检测技术、纳米技术、机器学习（ML）和物联网（IoT），重点介绍了它们在确保油井结构完整性方面的应用。先进的检测技术，利用无人驾驶车辆和机器人系统，可以优化无法到达区域的设备可达性，最大限度地减少人类暴露在危险环境中，并提供实时数据，以帮助检测设备裂缝和泄漏。纳米技术，如安装在套管上的纳米传感器，可以远程观察水泥性能，这是WI的关键组成部分，有效地实现了早期缺陷检测。此外，在井筒设备中使用纳米材料可以增强设备在重载和高温下的耐久性。在从所有可用来源收集数据之后，物联网设备（例如井筒的数字孪生版本）可以为井的未来阶段提供有价值的见解。通过根据机器学习预测结果调整参数，这些设置可以启动有效的响应计划，增强职业安全和态势感知。

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引用次数: 0

Impact of kerogen-fluid interactions on gas-water flow dynamics in shale 干酪根-流体相互作用对页岩气水流动动力学的影响

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-03-01 Epub Date: 2025-12-09 DOI: 10.1016/j.geoen.2025.214314

Xuan Yi , Kyung Jae Lee , Jiyoung Choi

The interaction between kerogen and various fluids is crucial for understanding gas-water flow behavior in shale, given that it directly influences wettability and flow dynamics and subsequently impacts the efficiency of hydrocarbon production. This study aims to examine the contact angle changes over time and their implications on gas-water flow under both hydrophilic and hydrophobic conditions in kerogen-bearing shale. The study involves experimental characterization utilizing various kerogen samples from Montney Formation and various fluids, including hydraulic fracturing fluid, brine, and deionized water, to investigate the contact angle changes over time. With the observation from experiments, empirical model is developed to capture the contact angle as a function of time. Subsequently, the analytical model is developed to describe gas-water flow behavior in shale, by employing fractal theory and quadratic Hagen-Poiseuille equation and considering time-varying contact angle incorporated into the boundary conditions. The impact of variables such as porosity, wetting phase thickness, wettability, and gas rarefaction on the flow behavior is discussed. This study provides a comprehensive understanding of gas and water flow behavior in shale formation, highlighting the importance of contact angle and wettability as its controlling factors. The proposed model offers valuable insights for envisioned investigation on porosity, water film thickness, gas adhesion thickness, gas rarefaction effects, and wettability alteration in gas-wet and water-wet conditions.

干酪根与各种流体之间的相互作用对了解页岩气水流动行为至关重要，因为它直接影响润湿性和流动动力学，进而影响油气生产效率。本研究旨在研究含干酪根页岩在亲水和疏水条件下接触角随时间的变化及其对气水流动的影响。该研究包括利用来自Montney地层的各种干酪根样品和各种流体（包括水力压裂液、盐水和去离子水）进行实验表征，以研究接触角随时间的变化。根据实验结果，建立了接触角随时间变化的经验模型。随后，利用分形理论和二次Hagen-Poiseuille方程，将时变接触角纳入边界条件，建立了描述页岩气水流动特性的解析模型。讨论了孔隙度、润湿相厚度、润湿性和气体稀薄度等变量对流体流动特性的影响。该研究提供了对页岩地层气水流动行为的全面认识，强调了接触角和润湿性作为其控制因素的重要性。该模型为研究气湿和水湿条件下的孔隙度、水膜厚度、气体粘附厚度、气体稀薄效应和润湿性变化提供了有价值的见解。

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引用次数: 0

Experimental investigation for nanoparticle emulsification and viscosity reduction system on enhancing sweep efficiency in cold heavy oil production 纳米颗粒乳化降粘体系提高冷稠油波及效率的实验研究

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-03-01 Epub Date: 2025-12-09 DOI: 10.1016/j.geoen.2025.214333

Qingyao Wu , Haoran Zheng , Bojun Wang , Hongyang Wang , Yibo Yang , Changfeng Xi , Pengcheng Liu

This study selected four viscosity reducers for comparative analysis: dodecyl trimethyl ammonium bromide (DTAB), sodium dodecyl benzene sulfonate (SDBS), alkylphenol ethoxylate (OP-10), and a composite system of nanosilica with alkylphenol ethoxylate (NANO-OP10). Through basic performance tests, different viscosity reducers were evaluated, with a focus on the synergistic effects of nanoparticle and viscosity reducer on emulsification and viscosity reduction in heavy oil. The results indicate that the nano-emulsified viscosity reducer NANO-OP10 demonstrated superior performance in reducing oil-water interfacial tension (IFT), improving emulsification efficiency, and enhancing emulsion stability. Based on comprehensive consideration of both fundamental performance and economic feasibility, the 0.4 % NANO-OP10 was selected for subsequent experiments. In subsequent sand-pack flooding experiments, the primary nano-viscosity reducer flooding increased the oil recovery rate by 12.8 %. A 12-h shut-in period allowed oil-water redistribution, followed by secondary viscosity reducer flooding, which further enhanced the recovery rate by 24 %. After two rounds of viscosity reducer flooding, the overall oil recovery increased significantly, reaching 55.1 %, demonstrating the excellent viscosity reduction and emulsification capabilities of NANO-OP10, along with its remarkable oil displacement performance. Parallel dual-tube sand-pack experiments and microfluidic experiments further validated that the nano-viscosity reducer NANO-OP10 effectively suppresses unstable fingering phenomena, reduces oil-water mobility ratios, enhances emulsification and mobilization of residual oil, and significantly enhances both sweep efficiency and oil recovery. This study presents an economically viable chemical-based viscosity reduction and displacement technology for efficient exploitation of heavy oil resources.

本研究选择了四种降粘剂：十二烷基三甲基溴化铵（DTAB）、十二烷基苯磺酸钠（SDBS）、烷基酚聚氧乙酸酯（OP-10），以及纳米二氧化硅与烷基酚聚氧乙酸酯（NANO-OP10）的复合体系进行对比分析。通过基础性能试验，对不同降粘剂进行了评价，重点研究了纳米颗粒与降粘剂对稠油乳化降粘的协同作用。结果表明，纳米乳化降粘剂NANO-OP10在降低油水界面张力（IFT）、提高乳化效率和增强乳液稳定性方面表现出优异的性能。综合考虑基本性能和经济可行性，选择了0.4% NANO-OP10进行后续实验。在随后的砂层充填驱油实验中，纳米降粘剂首次驱油使采收率提高了12.8%。关井时间为12小时，油水重新分布，随后进行二次降粘剂驱油，进一步提高了24%的采收率。经过两轮降粘剂驱油后，整体采收率显著提高，达到55.1%，说明NANO-OP10具有优异的降粘乳化能力，驱油效果显著。平行双管充填砂实验和微流体实验进一步验证了纳米降粘剂NANO-OP10能有效抑制不稳定指指现象，降低油水迁移比，增强剩余油的乳化和动员，显著提高波及效率和采收率。提出了一种经济可行的稠油资源高效开发的化学降粘驱技术。

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引用次数: 0

The progress of CO2 geothermal extraction based on different reservoir types: physicochemical effects and multi-factors influence 基于不同储层类型的CO2地热开采进展：物化效应及多因素影响

IF 4.6 0 ENERGY & FUELS

Geoenergy Science and Engineering

Pub Date : 2026-03-01 Epub Date: 2025-12-22 DOI: 10.1016/j.geoen.2025.214353

Yuanxiu Sun , Zhengyang Jia , Jianchao Li , Ming Li , Yangfan Tang

With the excessive consumption of fossil fuels and the further increase in CO₂ emissions, the global demand for energy is gradually rising. Vigorously developing renewable energy has become a crucial measure in the energy industry. As a kind of green renewable resource with huge reserves, geothermal energy is considered to be one of the most promising renewable resources. In the quest for efficient methods of geothermal energy extraction, CO₂ has demonstrated unique advantages. Compared to traditional systems that use water as the working medium, CO₂ exhibits superior fluidity, enabling it to circulate more efficiently within geothermal reservoirs. All of which can accelerate heat transfer, thereby significantly improving the efficiency of geothermal energy extraction. The types of geothermal reservoirs are summerized in this article, including three categories: hot dry rock, deep aquifers and depleted oil and gas reservoirs. Moreover, the study provides a review of the physicochemical phenomena that occur after CO₂ injection into geothermal reservoirs. These phenomena mainly include salt precipitation, CO₂-brine-rock geochemical reactions, and thermosiphon effects. Furthermore, the factors affecting CO₂ heat recovery are clarified. Finally, the obstacles and challenges faced by CO₂ heat recovery technology are pointed out, and the future research work is clarified.

随着化石燃料的过度消耗和二氧化碳排放量的进一步增加，全球能源需求正在逐步上升。大力发展可再生能源已成为能源产业发展的重要举措。地热能作为一种储量巨大的绿色可再生资源，被认为是最有前途的可再生资源之一。在寻找有效的地热能提取方法的过程中，二氧化碳显示出了独特的优势。与使用水作为工作介质的传统系统相比，CO2表现出优越的流动性，使其能够在地热储层中更有效地循环。这些都可以加速换热，从而显著提高地热能的提取效率。本文综述了地热储层的类型，包括热干岩、深部含水层和枯竭油气藏三大类。此外，本文还对CO2注入地热储层后的物理化学现象进行了综述。这些现象主要包括盐降水、co2 -盐水-岩石地球化学反应和热虹吸效应。并对影响CO2热回收的因素进行了分析。最后，指出了CO2热回收技术面临的障碍和挑战，并对未来的研究工作进行了明确。

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引用次数: 0