Dynamic, in-situ imaging of capillary imbibition in rock using simultaneous neutron and X-ray computed tomography

使用同步中子和 X 射线计算机断层扫描对岩石中毛细管渗吸进行动态原位成像

• 批准号: EP/N021665/1
• 负责人: Yukie Tanino
• 金额: $ 2.63万
• 依托单位: University of Aberdeen
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FN021665%2F1
• 关键词: Dynamic; situ; imaging; capillary; imbibition

The most common method of secondary oil recovery is waterflooding, whereby water is injected into a reservoir to displace the oil in the reservoir towards production wells. Under ideal conditions, the injected water (flood water) uniformly 'sweeps' the oil towards the wells. However, in fractured reservoirs, which contain around half of the world's oil reserves, the flood water preferentially flows through the network of fractures, leaving behind a large fraction of the original oil in the rock matrix. Then, more gradually, flood water in the fractures enters the rock matrix by buoyancy, diffusion, and spontaneous (capillary-driven) imbibition, displacing the oil that was left behind.Salient features of imbibition under uniformly water-wetting (hydrophilic) conditions are well established. However, many fundamental questions remain unanswered for imbibition under mixed-wet conditions characteristic of oil reservoirs, under which grain surfaces display heterogeneity in wettability at the pore scale and sub-pore scale. To design efficient oil recovery schemes for fractured reservoirs, the relationship between rock wettability and the imbibition behaviour (i.e., rate and ultimate oil recovery) must be determined quantitatively.Funds are requested for two members of the project team to travel to the National Institute of Standards and Technology (NIST) Center for Neutron Research in Gaithersburg, USA in a series of four trips to perform experiments at their X-ray/neutron imaging facility. We will dynamically image the displacement of oil within limestone samples by imbibing water for oils containing different wettability-altering constituents. Observed differences in imbibition behaviour will be correlated to the contact angle of the oil/brine interface on a calcite substrate measured independently; this macroscopic contact angle will be our measure of rock wettability.The work will be undertaken by a multidisciplinary team comprising academic researchers with a combined expertise in experimental fluid mechanics, rock mechanics, and medical imaging at University of Aberdeen, together with physicists in the Neutron Physics Group at NIST. To our knowledge, NIST is the only high flux user facility with simultaneous X-ray and neutron imaging capabilities. Moreover, NIST will provide us with four highly specialized, constant pressure mode syringe pumps which we need for establishing uniform initial oil saturation.Two key aims of the project are to consolidate the collaboration between the applicants and the named physicists at NIST and to evaluate the achievable specifications of the new combined X-ray/neutron imaging capability at NIST for our samples. This project will thus provide the basis for future work by the project team which will lead to a physically meaningful, predictive model for capillary-driven, two-phase flow in porous media under the full range of possible wettability and initial fluid distribution. Applications include petroleum engineering (oil recovery from fractured reservoirs), geological CO2 storage (migration of formation brine towards the injection well during well shut-in), geotechnical engineering (subsurface leakage from waste repositories), construction (water infiltration into concrete), and flood management, soil remediation, and irrigation (water infiltration in soil).

二次采油的最常见方法是注水，其中将水注入储层中以将储层中的油驱替到生产威尔斯。在理想条件下，注入的水（驱水）均匀地将油“扫”向威尔斯。然而，在含有世界石油储量约一半的裂缝性储层中，洪水优先流过裂缝网络，在岩石基质中留下大部分原始石油。然后，裂缝中的洪水通过浮力、扩散和自发（毛细管驱动）渗吸逐渐进入岩石基质，驱替留下的石油。然而，许多基本的问题仍然没有得到回答的渗吸下的混合潮湿的条件下的油藏，在此条件下，颗粒表面显示在孔隙尺度和亚孔隙尺度的润湿性的异质性。为了设计裂缝性油藏的有效采油方案，岩石润湿性与渗吸行为（即，需要为项目小组的两名成员提供经费，以便他们前往美国国家标准与技术研究所（NIST）位于盖瑟斯堡的中子研究中心，进行四次旅行，在该中心的X射线/中子成像设施进行实验。我们将动态图像的石灰岩样品中的石油的位移，通过吸收水的石油含有不同的润湿性改变的成分。所观察到的渗吸行为的差异将与独立测量的方解石基质上的油/盐水界面的接触角相关;这个宏观接触角将是我们对岩石润湿性的测量。2这项工作将由一个多学科的团队进行，该团队由阿伯丁大学的学术研究人员组成，他们具有实验流体力学、岩石力学和医学成像方面的综合专业知识，和NIST中子物理组的物理学家们一起。据我们所知，NIST是唯一一个具有同步X射线和中子成像能力的高通量用户设施。此外，NIST将为我们提供四个高度专业化的恒压模式注射泵，我们需要这些泵来建立统一的初始含油饱和度。该项目的两个关键目标是巩固申请人与NIST指定物理学家之间的合作，并评估NIST新的X射线/中子组合成像能力对我们样品的可实现规格。因此，该项目将为项目小组今后的工作提供基础，这将导致一个物理上有意义的预测模型，用于毛细驱动，多孔介质中的两相流在所有可能的润湿性和初始流体分布范围内。应用包括石油工程（从裂缝储层中采油）、地质CO2储存（在关井期间地层盐水向注入井迁移）、岩土工程（废物储存库的地下泄漏）、建筑（水渗入混凝土）、洪水管理、土壤修复和灌溉（水渗入土壤）。

项目成果

Characterisation of propagation of fractures in rocks using X-ray and neutron imaging

使用 X 射线和中子成像表征岩石中裂缝的扩展

• 发表时间: 2020
• 作者: Manoharran Girvani

A portable triaxial cell for beamline imaging of rocks under triaxial state of stress

用于三轴应力状态下岩石束线成像的便携式三轴单元

• DOI: 10.1088/1361-6501/abeb94
• 发表时间: 2021
• 期刊: Measurement Science and Technology
• 影响因子: 2.4
• 作者: Syed A

In-situ imaging of fractured rock and flow through them using simultaneous neutron and X-ray computed tomography, EPSRC

使用同步中子和 X 射线计算机断层扫描 (EPSRC) 对裂隙岩石和流经它们的流进行原位成像

• DOI: 10.21820/23987073.2017.7.61
• 发表时间: 2017
• 期刊: Impact
• 作者: Tanino Y