Visualizing and quantifying solvent-transport and bitumen-recovery mechanisms under core-plug conditions

蒸汽辅助重力排水是油砂资源开发中最常用的技术。然而，这项技术涉及大量的水和能源消耗，从而导致各种环境问题。注入溶剂等添加剂可以减少水和热量的消耗，最终优化回收过程并减少温室气体排放。本研究旨在通过实验研究在循环溶剂过程中从油砂岩心样品中将溶剂输送到沥青生产中的机理，并为现场规模的预测建立实验室数据模型。实验中使用的油砂和沥青样品来自于冷湖的Clearwater地层。第一阶段包括在油藏条件下使用定制设计的可视化单元进行的循环溶剂过程实验。该池使我们能够直观地看到多孔介质条件下的溶剂-沥青相互作用。对压力衰减、沥青回收和可视化数据的分析将有助于理解在注入溶剂以回收沥青期间在储油层中发生的相行为和输送机制。第二阶段包括对测量实验数据进行建模，以预测溶剂-沥青体系的相行为，并量化溶剂传输机制和沥青回收。本研究的结果有助于油砂生产商通过控制溶剂的类型和数量以及注入压力、浸泡时间和耗尽策略等操作参数来优化循环溶剂工艺。这一创新的研究计划有望为加拿大带来显著的环境和经济效益。

Steam assisted gravity drainage is the most commonly used technique for the development of oil-sandresources. However, this technique involves heavy consumption of water and energy, and thus, causes variousenvironmental issues. Injection of additives such as solvents has been implemented to reduce water and heatconsumption, ultimately optimizing the recovery process and reducing greenhouse gas emissions.This research aims to experimentally investigate the mechanisms responsible for solvent transport into andbitumen production from oil-sand core samples during cyclic solvent processes and to model laboratory data forfield-scale predictions. Oil-sand and bitumen samples used in the experiments are from the ClearwaterFormation at Cold Lake. The first phase consists of cyclic-solvent-process experiments using acustom-designed visualization cell under reservoir conditions. The cell allows us to visualize solvent-bitumeninteractions under porous media conditions. Analysis of the pressure-decay, bitumen recovery, andvisualization data will help to understand phase behavior and transport mechanisms that occur in the reservoirduring solvent injection for bitumen recovery. The second phase involves modeling of the measuredexperimental data to predict phase behavior of solvent-bitumen systems and to quantify solvent transportmechanisms and bitumen recovery.The outcomes of this study help oil-sand producers to optimize cyclic solvent processes by controlling the typeand amount of solvent, and the operational parameters such as injection pressure, soaking time, and depletionstrategy. This innovative research program is expected to bring significant environmental and economicbenefits to Canada.