Microfluidic Study of Application of Nanosuspension with Aluminum Oxide Nanofibers to Enhance Oil Recovery Factor During Reservoir Flooding

The paper presents the results of a comparative microfluidic study of the oil displacement process from a microfluidic chip simulating rock. Suspensions of spherical nanoparticles of silicon oxide (22 nm) and aluminum oxide (11 nm), as well as aluminum oxide nanofibers (8.7 nm in diameter and with an aspect ratio of 58), were used as displacing liquids. The nanofibers represent a unique new-generation crystalline material with a high aspect ratio. This work presents the first consideration of the use of aluminum oxide nanofibers as an additive for enhanced oil recovery. The comparative analysis has demonstrated that the addition of nanofibers can markedly enhance the oil recovery factor relative to the addition of spherical nanoparticles, other things being equal. Thus, in particular, it was demonstrated that the addition of nanofibers into the system allows for the greatest enhancement of the oil recovery factor, reaching a value of 25%, whereas the addition of spherical nanoparticles results in a maximum increment of approximately 10%. This is due to the fact that nanofiber additives have a tenfold stronger effect on the viscosity of nanosuspensions compared to similar additives of spherical particles. Nanosuspensions of aluminum oxide nanofibers exhibit non-Newtonian behavior at low concentrations. This opens the possibility of their extensive use in enhanced oil recovery.