Unfavorable mobility ratios in heterogeneous
reservoirs have resulted
in progressively poor waterflood sweep efficiency and diminishing
production. In order to address this issue, our study has developed
amphiphilic-structured nanoparticles aimed at enhancing the microscopic
displacement capability and oil displacement efficiency. First, the
transport process of Janus nanoparticles in porous media was investigated.
During the water flooding, Janus nanoparticle injection, and subsequent
water flooding stages, the injection pressure increased in a “stepped”
pattern, reaching 0.023, 0.029, and 0.038 MPa, respectively. Second,
emulsification effects and emulsion viscosity experiments demonstrated
that the amphiphilic structure improved the interaction at the oil–water
interface, reducing the seepage resistance of the oil phase through
emulsification. In porous media, Janus nanoparticles transported with
water exhibit ‘self-seeking oil’ behavior and interact
with the oil phase, reducing the viscosity of the oil phase from 19
to 5 mPa·s at 80 °C. Finally, the core model displacement
experiment verified the characteristics of Janus nanoparticles in
improving the oil–water mobility ratio. Compared with the water
flooding stage, the recovery percent increased by 20.8%, of which
13.7% was attributed to the subsequent water flooding stage. Utilizing
the asymmetry of the Janus particle structure can provide an effective
path to enhanced oil recovery in inhomogeneous reservoirs.