Study of Microscopic and Macroscopic Displacement Behaviors of Polymer Solution in Water-Wet and Oil-Wet Media

• Published in: Transport in porous media Vol. 89; no. 1; pp. 97 - 120
• Main Authors: Emami Meybodi, Hamid, Kharrat, Riyaz, Wang, Xiaoqi
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.08.2011; Springer; Springer Nature B.V
• Subjects: Civil Engineering; Classical and Continuum Physics; Displacement; Earth and Environmental Science; Earth Sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Enhanced oil recovery; Exact sciences and technology; Floods; Geotechnical Engineering & Applied Earth Sciences; Glass; Hydrocarbons; Hydrogeology; Hydrology. Hydrogeology; Hydrology/Water Resources; Hydrolysis; Image processing; Industrial Chemistry/Chemical Engineering; Media; Molecular weight; Organic chemistry; Pollution, environment geology; Polymer chemistry; Polymer films; Polymers; Product design; Rheological properties; Rheology; Sedimentary rocks; Viscosity; Viscosity ratio; Water film; Wettability; Wettability; Polymer flooding; Glass micromodel; Oil recovery; Microscopic and macroscopic displacement; experimental studies; floods; Spot; concentration; recovery; transport; reservoir properties; viscosity; solution; connate waters; displacements; wettability; polymers; porous media; hydrolysis
• ISSN: 0169-3913; 1573-1634
• DOI: 10.1007/s11242-011-9754-5

Performance of a polymer flood process requires the knowledge of rheological behavior of the polymer solution and reservoir properties such as rock wettability. To provide a better understanding of effects of polymer chemistry and wettability on the performance of a polymer flood process, a comprehensive experimental study was conducted using a two-dimensional glass micromodel. A series of water and polymer flood processes were carried out at different polymer molecular weights, degrees of polymer hydrolysis, and polymer concentrations in both water-wet and oil-wet systems. Image processing technique was applied to analyze and compare microscopic and macroscopic displacement behaviors of polymer solution in each experiment. From micro-scale observations, the configuration of connate water film, polymer solution trapping, flow of continuous and discontinuous strings of polymer solution, piston-type displacement of oil, snap-off of polymer solution, distorted flow of polymer solution, emulsion formation, and microscopic pore-to-pore sweep of oil phase were observed and analyzed in the strongly oil-wet and water-wet media. Rheological experiments showed that a higher polymer molecular weight, degree of hydrolysis, and concentration result in a higher apparent viscosity for polymer solution and lower oil–polymer viscosity ratio. It is also shown that these parameters have different impacts on the oil recovery in different wettabilities. Moreover, a water-wet medium generally had higher recovery in contrast with an oil-wet medium. This experimental study illustrates the successful application of glass micromodel techniques for studying enhanced oil recovery (EOR) processes in five-spot pattern and provides a useful reference for understanding the displacement behaviors in a typical polymer flood process.