Janus nanoparticles (JNPs) exhibit significant promise for enhancing oil recovery (EOR). However, their large-scale field deployment remains challenging. A key challenge lies in the insufficient understanding of how the physical characteristics of JNPs influence their transport behavior and microscopic oil displacement mechanisms in porous media. In this study, molecular dynamics (MD) simulations are employed to systematically investigate the displacement dynamics of oil trapped on rough surfaces mediated by JNPs of various geometries. The results reveal that particle shape critically affects both the pinning resistance encountered at groove edges and the accumulation patterns along lateral walls. These shape-dependent adsorption configurations in turn modulate local wettability and ultimately dictate the efficiency of oil removal from nanoscale grooves. Spherical and ellipsoidal JNPs demonstrate superior displacement performance when the groove surface is coated with a thin oil film. However, under conditions involving thick oil films, spherical JNPs exhibit limited penetration into narrow grooves due to their stable orientation at the oil–water interface, which reflects strong interfacial stability. In contrast, disc, rod, and ellipsoidal JNPs effectively disrupt thick oil films via a cooperative mechanism termed “aggregation and flipping”. Among all evaluated geometries, ellipsoidal JNPs consistently deliver optimal EOR performance across various oil film conditions. These findings provide molecular-level insights into shape-governed JNP performance in EOR, offering valuable guidance for the rational design and application of shape-optimized JNPs in oilfield operations.

High heat loss, substantial energy consumption, considerable CO₂ emission and low thermal utilization efficiency are main challenges in the thermal-based production methods applied in high viscous oil reservoir. To address these limitations while achieving both high oil recovery and reduced carbon footprint, this perspective systematically investigates an enhanced high viscous oil recovery method that integrates in-situ pyrolysis with downhole electric heater. Laboratory experiments and field applications demonstrate that this novel technology offers multiple advantages over conventional thermal-based methods, such as higher thermal utilization efficiency, lower carbon emissions and reduced energy consumption. In this novel technology, with high temperature in the reservoir, inducing pyrolysis and cracking reactions in high viscous oil, significantly reducing oil viscosity and enhancing oil recovery factor. Thereby, this novel method presents a viable, low-carbon, and efficient pathway for future development of high viscous oil resources.

This paper investigates the influence of reaction atmosphere and operation parameters of the lightening process under high temperature and high pressure on high-viscosity shale oil using an experimental approach. Two types of experiments were implemented, one involving a thermogravimetric analyzer and another using an autoclave to carry out the lightening process. By these two kinds of experiments, the effects of reaction atmosphere and operation parameters on the lightening efficiency were clarified. As for the reaction atmosphere, the effects of CO₂, N₂ and air were separately evaluated. As for the operation parameters, the effects of heating rate and formation rock were investigated. The results indicate that under a CO₂ atmosphere, the lightening reaction is more intense than that under the other two gas phases, and it gains the highest reaction rate. Part of the minerals in the formation rock can be treated as catalyst in the shale oil lightening process. With the formation rock being present, the reaction rate increases significantly and higher contents of light components are obtained in both the lightened shale oil and gas phase. For the kinetic parameters in the lightening process, proportional relationships between the kinetic parameters and heating rates under CO₂ atmosphere with and without formation rock were identified. The findings of this study can provide guidance for enhancing high-viscosity shale oil using an in-situ lightening process.