Preparation Of A Seawater Based Nano-material For Decompression And Augmented Injection And Study Of Its Interfacial Adhesion Mechanism

Many difficulties have been encountered while recovering oil & gas from low permeability reservoirs,such as micro-nano meter pore throat,low permeability,low recovery,difficulty in energy supply,and low flooding efficiency,etc.Nano materials,which has been studied and applied for enhanced oil recovery process,stand out for their superb qualities,including nano scale,easy access to reservoirs,massive surface energy and excellent dispersibility.However,their adhesion mechanism on the solid-fluid and fluid-fluid interfaces have not yet been settled for discussion.By developing a novel composite of nano material and surfactant that is aimed for decompression and augmented injection purpose,various qualities of nano material on interfaces were studied.The ability of nano materials to stabilize interface,change wettability of solid surfaces,enhance stability of emulsions and improve injection condition were studied with methods including inspection on emulsions through microscope,investigation on interface properties through micro fluidic device and high speed camera,micro-PIV experiments about the flow behavior of nano material dispersion in micro fluidic devices.The experiment results show that the novel composite of nano material and surfactant has a good performance concerning the stability of interfaces and enhancement of decompression and augmented injection.The recipe for novel active nano material contains 2% HS-30 silica nanoparticle + 0.014-0.5mol/L and above 4mol/L LH-2 surfactant.Experiments like micro fluidic investigations and sand core simulations proved the superb ability of such composites.Mechanisms of nano materials stabilizing interfaces and decompression and augmented injection were discussed.