Heavy oil recovery using ASP flooding: A pore‐level experimental study in fractured five‐spot micromodels

Abstract

Although alkaline-surfactant-polymer (ASP) flooding has proven efficient for heavy oil recovery, the displacement mechanisms and efficiency of this process should be discussed further in fractured porous media. In this study, several ASP flooding tests were conducted in fractured glass-etched micromodels with a typical waterflood geometrical configuration, i.e. five-spot injection-production pattern. The ASP flooding tests were conducted at constant injection flow rates but different fracture geometrical characteristics. The ASP solutions consisted of five polymers, two surfactants, and three alkaline types. It was found that using synthetic polymers, especially hydrolyzed polyacrylamide with high molecular mass, as well as cationic surfactant increases the ultimate recovery. The location of the injection well with respect to the fracture system plays a significant role in the ASP flooding performance, i.e. an increase in the angle associated with the longitudinal extension of fractures with respect to the main flow direction resulted in enhanced oil recovery and also postponed the wetting phase breakthrough time. Mechanistic study of this displacement process revealed that dispersive and diffusive behaviour of the ASP front enhanced the fluid transport from fracture to matrix and increased the microscopic displacement efficiency. Emulsification and coalescence mechanisms were responsible for ASP frontal advancement. Residual oil in the invaded region, which was observed in the form of discontinuous oil ganglia dispersed in the invaded pore bodies or in the form of pendular bridges formed around some of the solid particles, was mobilized in the form of oil wads through the droplets of the displacing phase.

Experimental methods in chemical engineering: Contact angles

“…In five of these papers, CA is only an inlet parameter in a model or a numerical simulation. The twelve remaining involve experimental measurements, all of which were performed with an optical goniometer or derived instruments . The latter enables analysis at a liquid/liquid/solid or a liquid/gas/solid interface instead of a gas/liquid/solid one (Figure ).…”

“…The latter enables analysis at a liquid/liquid/solid or a liquid/gas/solid interface instead of a gas/liquid/solid one (Figure ). Works performed with an optical goniometer mainly employed the static sessile drop method with only two employing dynamic methods . Three studies included qualitative surface analysis through scanning electron microscopy images to estimate the substrate roughness: Ahmmed et al published the only manuscript in which both advancing and receding contact angles are reported and in which an estimation of the hysteresis is provided.…”

Improved fracturing fluid using: Organic amino boron composite crosslinker with BN covalent bond

“…In addition, the viscosity of polymer is closely related to the opening of reservoir fractures and the passage of pore size. [20][21][22][23][24] Therefore, it is very important to study the change of viscosity at shear rate.…”

“…Such polymers are usually non‐Newtonian fluids that are commonly characterized with nonlinearity of shear. In addition, the viscosity of polymer is closely related to the opening of reservoir fractures and the passage of pore size . Therefore, it is very important to study the change of viscosity at shear rate.…”

Lost Gas Mechanism and Quantitative Characterization during Injection and Production of Water-Flooded Sandstone Underground Gas Storage

“…This experiment is widely applied in the field of oil displacement mechanism research, such as the mechanism research of nitrogen foam flooding [27], and the displacement mechanism of heavy oil [28]. However, these experiments are not designed for the high-intensity injection production process of underground gas storage, the injection pressure of these experiments are generally lower than 10 MPa.…”