Enhanced oil recovery (EOR) seeks to improve the recovery of oil from existing mature oil fields. It targets the oil left behind after conventional recovery by natural reservoir drive and water injection. The injection of surfactant polymer chemicals can enhance oil recovery by reducing the interfacial tension, allowing more oil to be released from its host rock and improving the flood conformance. In this study, the principles and parameters of chemical surfactant polymer EOR mechanisms, which mobilise, displace and transport residual oil (i.e. build an effective oil bank) after water injection were investigated. The current understanding of when, and under what conditions, an oil bank is formed and maintained is limited. This is relevant in core-flow experiments that need to be appropriately interpreted and scaled, from the centimetre to the field scale, in various steps. Various factors that influence the dynamics of building a stable oil bank were evaluated, using an extensive core-flow experimental study with the aid of computed tomography scanning....@en

In this research, we investigate and characterize the oil bank mobilization on a single-mineral porous medial “Fontainebleau sandstone” (Al Saadi, 2017). Chemicals (surfactant and polymer) are used to mobilize the trapped/residual oil and build up the oil bank. The understanding of favorable physical, chemical and spatial conditions of when and how an oil bank is formed is very limited. It is more applicable when coreflow experiments are upscaled from core scale to field scale Coreflow experiments were carrried out in high end setup which provide us with the robust, accurate and repeatable experimental data for oil mobilization process from 7 cm to one meter scale core samples. Data integrity of coreflow experiments are insured by two ways: repeating the experiments and reproducing the experimental results; improving the precesion and accuracy. Additionally, some of the coreflow experiments were carried out under CT scanner where the mobilization process of oil bank is visualized, monitored and characterized. For experimental data Interpretation; we used analytical (JBN Method) and in house numerical simulator to produce accurate relative permeability curves for various core lengths. This experimental relative permeability interpretation provides us insight into the mechanisms and dynamics of the oil mobilization process in natural porous media.@en

Characterizing and understanding porous media is essential prior to standardized core-flow experiments, to investigate oil mobilization on a single-mineral porous medium with a limited permeability/porosity band width, and a homogenous pore- and grain-framework. Literature shows that one almost pure quartz horizon in the Fontainebleau sandstone meet these preconditions. Fresh samples were gathered from the “Gres de Fontainebleu and Cie” Quarry. Knowing the depositional environment and burial history, we measured and quantified spatial attributes of the matrix by CTS image analysis, associated stereological measurements, statistical 2D/3D reconstructions and petrophysical laboratory measurements. Permeability, porosity, capillarity, specific surface, pore framework and pore coordination number distribution were measured and compared with literature. This new database provides a comprehensive review on the Fontainebleau sandstone from micro-scale to meter scale for a porosity bandwidth of 0.05 – 0.11 and permeability bandwidth of 10 – 400 mD. The combined measurements, petrophysical and spatial properties support, are used for prediction, modeling and interpretation of comparative core-flow experiments meant for oil mobilization by chemical injections (surfactant & solvent), i.e. chemo-physical interaction of rock/fluids and multi-phase fluid/fluid adsorptions. Similarly, mapping the pore framework helps modelling the mobilization and transport of the oil from mm-scale to m-scale. @en