Role of Ionic Composition and Interaction in Oil-Water-Rock Systems during Enhanced Oil Recovery Processes involving Low-Salinity Fluid and CO2 Injection

低矿化度流体和 CO2 注入提高采收率过程中油-水-岩石系统中离子组成和相互作用的作用

• 批准号: RGPIN-2019-04841
• 负责人: Sarma, Hemanta
• 金额: $ 2.4万
• 依托单位: University of Calgary
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=684997
• 关键词: Role; Ionic; Composition; Interaction; Oil

Today, exploration for new oilfields is a high-risk venture due to the low oil price. Therefore, a logical lower-cost alternative is to target and extract residual oil from the already discovered and developed oil reservoirs, particularly the Canadian light-oil reservoirs with an estimated oil reserve of 5.5 billion barrels. Even a single percent improvement in the recovery of oil from these reservoirs will yield rich dividends for Canada. My program has a direct relevance to such reservoirs in Canada and elsewhere, where the traditional waterflood has performed poorly due to unfavorable rock wettability and high post-flood residual oil saturation, thus making a difference between a successful and a marginal project, particularly in the current low-oil price environment. The unfavorable rock wettability, in particular, leads to poor relative permeability characteristics for the oil, and this in turn, causes the premature breakthrough of the injected water in production wells resulting in a much lower-than-expected oil recovery factor.**** My research aims to find solutions to overcome or diminish the effects of unfavorable rock wettability by making changes in the ionic composition and salinity of the injected water. In this program, I will also explore how some of these light-oil Canadian reservoirs can be utilized, concomitantly, to sequester CO2 and recover oil. Therefore, this program has dual objectives: EOR and partial CO2 sequestration through an EOR process.**** A systematic approach has been charted to meet the program objectives through a well-defined work plan comprising both modeling and experimental studies. The program includes a fundamental study of water geochemistry and key rock-fluid geochemical reactions under various ionic compositions. This is followed by a study of CO2 EOR with an optimized composition of the injected water to partly sequester CO2 in the reservoir. It will generate a new water chemistry to improve waterflood oil recovery as well as quantify the CO2 sequestration potential during CO2 EOR processes.**** Geochemical reactions and transport models developed in the program will be validated through specially-designed laboratory tests to study oil-rock-brine interactions, wettability alteration, relative permeability and surface-charge behavior, ionic transport, and finally, the oil recovery and CO2 fixation in the rock. This will be followed by additional validation using representative rock-fluid samples and data from a few selected Canadian light-oil reservoirs to establish the lab-to-field linkage of the program outcomes.**** During the course of the program, I will provide comprehensive research-based training in advanced modeling and laboratory studies to 7 HQPs, who will also engage synergistically in scholarly outreach, contributions and interactions with peers in dissemination of our findings through refereed journals, conferences and other such knowledge-sharing platforms, like forums and workshops.***

如今，由于低油价，勘探新油田是一项高风险的冒险。因此，一个合乎逻辑的低成本替代方案是瞄准已经发现和开发的油藏，特别是估计石油储量为55亿桶的加拿大轻质油藏，并从这些油藏中开采剩余油。即使这些储油层的石油采收率提高一个百分点，也会给加拿大带来丰厚的红利。我的项目与加拿大和其他地方的此类油藏有直接关系，在这些地方，由于不利的岩石润湿性和洪水后较高的剩余油饱和度，传统的注水开发表现不佳，因此决定了一个成功的项目和一个边缘项目之间的差异，特别是在当前的低油价环境下。特别是不利的岩石润湿性导致原油的相对渗透率特性较差，进而导致注入水在生产井中过早突破，导致原油采收率远低于预期。*我的研究目的是通过改变注入水的离子组成和矿化度来克服或减弱岩石润湿性不利的影响。在这个项目中，我还将探索如何同时利用加拿大这些轻质油气藏中的一些来隔离二氧化碳和回收石油。因此，该方案具有双重目标：提高采收率和通过采油过程部分封存二氧化碳。*已经制定了一种系统的方法，通过包括建模和实验研究在内的明确定义的工作计划来实现方案目标。该计划包括水地球化学的基础研究和在不同离子组成下的关键岩石-流体地球化学反应。随后进行了二氧化碳提高采收率的研究，并优化了注入水的成分，以部分隔离油藏中的二氧化碳。它将产生一种新的水化学，以提高水驱石油采收率，并量化二氧化碳提高采收率过程中的二氧化碳封存潜力。*该计划中开发的地球化学反应和传输模型将通过专门设计的实验室测试进行验证，以研究石油-岩石-卤水相互作用、润湿性变化、相对渗透率和表面电荷行为、离子传输，最后是石油回收和二氧化碳在岩石中的固定。随后，将使用几个选定的加拿大轻质油气藏的代表性岩石流体样本和数据进行进一步验证，以建立项目成果的实验室到现场联系。*在项目过程中，我将为7名HQP提供基于研究的综合高级建模和实验室研究培训，他们还将协同参与学术拓展、贡献和与同行的互动，通过经评审的期刊、会议和其他类似的知识共享平台，如论坛和研讨会，传播我们的发现。*