A Pore-level Investigation of Surfactant-crude Oil Displacements Behavior in Fractured Porous Media Using One-quarter Five Spot Micromodels

作者：Kianinejad A; Rashtchian D^*; Ghazanfari M H; Kharrat R

来源：Energy Sources, Part A: Recovery, Utilization, and Environmental Effects , 2014, 36(7): 727-737.

DOI：10.1080/15567036.2010.540632

• surfactant
• five-spot micromodel
• displacement behavior
• fracture geometrical properties
• experimental

Despite numerous studies, there is a lack of fundamental understanding about the displacement behavior of surfactant-crude oil systems under the influence of different fractures%26apos; geometrical properties in five-spot systems. In this work, a series of flow visualization experiments were carried out on one-quarter five spot glass micromodels at various fractures%26apos; geometrical properties, such as fracture density and fracture continuity, under oil-wet condition. The influences of injection of Linear Alkyl Benzene Sulfonate and Sodium Dodecyl Sulfate surfactants as well as the effect of fracture geometrical parameters, on macroscopic and microscopic displacement behavior have been investigated. The micromodels were initially saturated with crude oil. Precise analyses of the high quality pictures, which were taken during experiments, were used to explore the surfactant%26apos;s displacement efficiency. It has been found that two mechanisms govern such a process at the pore scale. One is responsible for decreasing the residual oil saturation and the other mechanism is increasing the matrix-fracture interactions through the porous media. The experimental results show that the magnitude of interfacial tension between the existing fluids was the most important parameter that altered the flow behavior at pore level. The observations revealed that high penetration of surfactant solutions from fractures into the matrixes perfectly postponed the breakthrough time and increased the oil recovery. As a result of better dispersion of surfactant through the matrix, it has been found that the higher fracture density yields a higher oil recovery. The media containing continuous fractures showed that higher oil recovery compared to discontinuous fractures. The results also showed that the average oil recovery during water injection is a strong function of the fracture properties, whereas use of Sodium Dodecyl Sulfate solution extremely reduces the effect of fracture geometrical properties. The results of this work can be helpful to better understanding the surfactant-crude oil displacements in fractured reservoirs.

• 出版日期2014-4-3
• 单位中国石油大学（北京）