Preparation of Amphiphilic Janus-SiO Nanoparticles and Evaluation of the Oil Displacement Effect.

In order to meet the requirements of tertiary oil recovery technology in a low-permeability, dense, and high-salt reservoir, gaseous SiO nanoparticles were modified with trichloro(octyl)silane and aminopropyl triethoxysilane by interface protection modification, and amphiphilic Janus-SiO nanoparticles with hydrophobic carbon chain and hydrophilic amino group were prepared. The basic properties of amphiphilic nanoparticle dispersion were evaluated by surface interfacial tension and wettability tests, and the oil displacement effect of amphiphilic nanoparticle dispersion was investigated. The results show that the size distribution of Janus-SiO nanoparticles with n-octyl as the hydrophobic carbon chain and amino group as the hydrophilic headgroup is uniform, and they have good dispersion in mineralized water.

Evaluation of the Driving Effect of the CO Viscosity Enhancer Composite System in Extra-Low Permeability Sandstone Reservoirs.

CO flooding is an important technology to enhance oil recovery and realize effective storage of CO in ultra-low permeability reservoir. However, due to poor reservoir properties, strong interlayer heterogeneity, and unfavorable mobility ratio of CO, gas channeling easily occurs, resulting in low recovery. Chemically assisted CO thickening technology has been developed to control the gas flow rate and improve the CO repulsion effect.

CO-Low Interfacial Tension Viscoelastic Fluid Synergistic Flooding in Tight Reservoirs.

Tight oil reservoirs have poor physical properties, insufficient formation energy, and low natural productivity. CO flooding is an important technical mean that enhances the oil recovery of dense reservoirs and achieves effective CO sequestration, but strong heterogeneity of the tight oil reservoir usually results in gas channeling and poor enhanced oil recovery effect. The existing methods to prevent gas channeling are mainly to use the small-molecule amine system and the polymer gel system to plug fracture and high permeability channels.