The purpose of this study is to enhance the quality of heavy oil through refinement using aquathermolysis with the simultaneous injection of steam and thermally stable nonionic surfactants (NS). To achieve this, the NS R-PPG of the nonionic type was synthesized, and the optimal product structures were characterized using infrared (IR) methods. Furthermore, the thermal stability of the synthesized NS R-PPG was investigated in line with the requirements for surfactants used in heavy oil applications. Subsequently, the study delved into investigating the hydrothermal upgrading of heavy oil with a catalyst, involving the joint participation of steam and surfactants at a temperature of 250 °C. Additionally, we assessed the improved oil characteristics resulting from the experimental process through SARA analysis, elemental analysis, GC, and viscosity reduction evaluations. The experimental results demonstrated distinct effects concerning the presence and absence of surfactants on heavy oil. Based on these findings, we conclude that surfactants play a crucial role in dispersing asphaltene clusters, thereby facilitating the decomposition process under mild thermobaric conditions, leading to a noticeable increase in the content of light fractions. Furthermore, as per the results of the elemental analysis, surfactants contribute significantly to the desulfurization of heavy oil. Overall, the incorporation of surfactants during hydrothermal upgrading resulted in an irreversible reduction in the viscosity of heavy oil, thereby enhancing its overall quality.

In this work, a synthesis of an oil-soluble iron-based catalyst precursor was carried out and its efficiency was tested in a laboratory simulation of the aquathermolysis process at different temperatures. The rocks of the Usinskoe field from the Permian deposits of the Komi Republic, obtained by steam-gravity drainage, and the iron-based catalyst precursor, as well as the products of non-catalytic and catalytic aquathermolysis, were selected as the object of study. As a result, it was found that the content of alkanes in the samples after thermal steam treatment (TST) at 300 °C increased 8-fold compared to the original oil, and the content of cycloalkanes in the sample with the catalyst increased 2-fold compared to the control experience. This may indicate that not only the carbon-heteroatom bonds (C-S, N, O) but also the C-C bonds were broken. It also shows that increasing the iron tallate concentration at TST 300 °C leads to a decrease in the molecular mass of the oil compared to the control experiment. According to SEM, the catalyst is nanodisperse particles with a size of ≈60–80 nm, which are adsorbed on the rock surface, catalyst removal occurs at a small scale.

The paper is devoted to study of the parametric resonance of torsional vibrations caused by large-amplitude flexural vibrations of cantilevered plates. In this study we considered the first two resonant modes of flexural vibrations. The analytical study of the original problem which is reduced to Hill equation, is based on the WKB approximation. According to the obtained results, we built a map of instability gaps in the plane of the two process control parameters. The conclusions are made about the possibility of experimentally detection the studied effect in real systems.

In this study, an examination was conducted of the influence of iron tallate on the composition and properties of highly viscous oil from the Strelovskoye deposit in the Samara region under thermal–catalytic treatment (TCT). The research revealed that the dynamic viscosity of the oil following TCT at 300 °C, with a measurement temperature of 20 °C, decreased by a factor of 8 in comparison to the initial sample and nearly 4.5 times compared to the control sample at the 96-h mark. The most promising results in reducing the pour point temperature to 7 °C were identified following a 96-h TCT at 300 °C. This reduction was attributed to the decrease in paraffin content facilitated by the presence of the catalyst. According to the ICP-MS results, the extraction of the catalyst with the oil amounted to only 1%. This indicates that during the implementation of TCT within the reservoir, the catalyst is likely to adsorb onto the rock surfaces.