Synergistic Effect of Asphaltene, Resin, and Wax Improving the Emulsification and Interfacial Properties of a High-Phase-Inversion Thin Oil.

Nowadays, high-phase-inversion in situ emulsification technology has shown great potential in enhancing oil recovery from high-water-cut thin-oil reservoirs. However, emulsification characteristics, interfacial properties, and the mechanism of high phase inversion have not been systematically described. In this study, an emulsification experiment was conducted to investigate the effects of shear time, shear rate, and temperature on the phase inversion of thin oil.

A Feasibility Study on Enhanced Oil Recovery of Modified Janus Nano Calcium Carbonate-Assisted Alkyl Polyglycoside to Form Nanofluids in Emulsification Flooding.

Emulsification flooding can effectively enhance crude oil recovery to solve the problem of petroleum shortage. In this work, a modified Janus Nano Calcium carbonate (JNC-12) with a particle size of 30-150 nm was synthesized, and an in situ emulsification nanofluid (ISEN) was prepared with JNC-12 and alkyl polyglycoside (APG). Scanning electron microscope (SEM) showed that the dispersion of JNC-12 in air or APG solution was better than Nano Calcium carbonate (Nano CaCO).

Microscopic Oil Displacement Mechanism of CO in Low-Permeability Heterogeneous Glutenite Reservoirs in the Junggar Basin.

Carbon dioxide (CO) flooding is a promising method for developing low-permeability heterogeneous glutenite reservoirs (LPHGRs) featured with low natural energy. Herein, the focus of this work was to study the microscopic oil displacement mechanism of CO in LPHGRs. First, the micropore structure and mineral composition of LPHGRs were analyzed, and the effect of CO on low-permeability reservoirs was then studied.

W/O high internal phase emulsions (HIPEs) stabilized by a piperazinyl based emulsifier.

In this study, a piperazinyl-based emulsifier (EA/AMPA) was synthesized to prepare water-in-oil (W/O) high internal phase emulsions (HIPEs). Using kerosene as the oil phase, stable HIPEs with internal phase fractions of up to 98% were prepared. This enabled the EA/AMPA to have a high efficiency, as the HIPEs with a 90% internal phase fraction could be easily prepared with 0.

Experimental Study on Supercritical CO Huff and Puff in Tight Conglomerate Reservoirs.

A tight conglomerate reservoir is a kind of unconventional reservoir with strong heterogeneity, and CO injection is an economical and environmentally friendly method to enhance tight oil recovery. Supercritical CO is a very promising fluid medium for unconventional reservoir development due to its gas-liquid dual properties. In this study, the production effects of supercritical CO and non-supercritical CO in tight conglomerate reservoirs were quantitatively analyzed by huff and puff simulation experiments conducted under reservoir conditions (formation pressure 37 MPa, temperature 89 °C).

Self-assembly in amphiphilic spherical brushes.

The structure of amphiphilic spherical brushes, consisting of the nano-SiO core, the hyperbranched polyamidoamine subshell, and a grafted layer of long hydrophobically modified polyacrylamide (HMPAM) chains, in aqueous solution was analyzed and described in the framework of the original mean-field approach. The scaling estimations of the hydrodynamic radius of such polymer brushes as a function of the number of grafted macromolecules allow concluding that the HMPAM shells are in a globular state and that the region of the stretched chains adjacent to the grafting surface is a minor part of the grafted macromolecules and does not have a significant impact on the self-assembly of the HMPAM shell caused by the complex hydrophobic-hydrophilic composition of their monomer units. In mean-field theory, the amphiphilic nature of HMPAM was taken into account by attaching the hydrophobic side group H to some fraction of monomer units of the hydrophilic P backbone.

Experimental Study on Enhanced Oil Recovery Method in Tahe High-Temperature and High-Salinity Channel Sand Reservoir: Combination of Profile Control and Chemical Flooding.

On account of the intralayer and interlayer heterogeneity, high temperature (110 °C), and high salinity (224,919 mg/L) of Tahe channel sand reservoir, single profile control or chemical flooding cannot greatly enhanced oil recovery. The goal of the current research was to optimize a polymer gel formula that was suitable for high-temperature and high-salinity reservoirs, screen an appropriate chemical flooding method, and determine the efficiency of the combination of profile control and chemical flooding. Experimental results indicated that the formed polymer gel could maintain relatively high strength after aging for 30 days.

Scalable synthesis of core-shell microgel particles using a 'dry water' method.

This proof-of-concept study demonstrates a facile and scalable 'dry water' method for producing micrometer-sized microgel particles by use of 'water-in-air' droplets as micro-reactors. Solid microgel particles could be easily produced by this method with no further purification. The microgel particles comprise of porous hydrophobic shells and hydrophilic cores and could absorb both oil and water.

CH Nanobubbles on the Hydrophobic Solid-Water Interface Serving as the Nucleation Sites of Methane Hydrate.

The surface hydrophobicity of solid particles plays a critical role in the nucleation of gas hydrate formation, and it was found that the hydrophobic surface will promote this nucleation process, but the underlying mechanism is still unveiled. Herein, we proposed for the first time our new theory that the formation of methane nanoscale gas bubbles on the hydrophobic surface provides the nuclei sites for further formation of methane hydrate. First, we studied the effect of hydrophobicity of particles on the nucleation of hydrate.

A POSS based hydrogel with mechanical robustness, cohesiveness and a rapid self-healing ability by electrostatic interaction.

A molecularly dispersed nano-material called POSS-NH-AA was synthesized to construct a hybrid hydrogel with a rapid self-healing ability (stress 8 kPa) and excellent mechanical performance (a strain of 4683% and a stress of 37.8 kPa). The hydrogel also exhibits good cohesiveness to materials, such as plastics, glass and iron.

Stabilization of Foam Lamella Using Novel Surface-Grafted Nanocellulose-Based Nanofluids.

To solve the potential risk of present oilfield chemistries to subterranean environment, our group contributes to the development of "green" petroleum production processes. This proof-of-concept research studied the well-defined nanocellulose-based nanofluids, i.e.