An evaluation of modified silica nanoparticles' efficiency in enhancing oil recovery of light and intermediate oil reservoirs

The role of nanoparticles in enhancing oil recovery from oil reservoirs is an increasingly important topic of research. Nanoparticles have the properties that are potentially useful for enhanced oil recovery processes, as they are solid and two orders of magnitude smaller than colloidal particles. This paper presents a comparison between the efficiency of modified silica nanoparticles in enhancing oil recovery from two different Iranian light and intermediate oil reservoirs. The mechanisms used to recover additional oil would be oil-water interfacial tension reduction and wettability alteration. Oil phase contact angles and oil-water interfacial tensions were measured in the absence and the presence of nano fluids' different concentrations (1-4 g/L). Results showed that the interfacial tension reduces dramatically in the presence of nanoparticles for both light and intermediate oil. In addition oil phase contact angle results showed a transformation of rock wettability from water-wet toward oil-wet condition. However, these nanoparticles are more capable in the reduction of the interfacial tension and the alteration of wettability in the case of light oil reservoir. A comparison between recovery results indicated that these nanoparticles are more efficient in light oil reservoirs and produce more incremental amount of oil after primary and secondary processes.