Chemistry and Technology of Fuels and Oils最新文献

The CO₂ enhanced oil recovery(EOR) technology is widely utilized in the development of shale oil reservoirs. However, reservoir plugging issues often occur during the CO₂ injection process, leading to reduced onsite development efficiency. Currently, the mechanism behind reservoir plugging is still unclear. Therefore, this research selects Jimsar crude oil from Xinjiang to conduct CO₂ displacement experiments on shale cores and analysis of crude oil components. A comparative analysis is conducted with previous studies to explore the plugging mechanism. The research results demonstrate that core plugging occurs when the displacement pressure exceeds 25 MPa, resulting in a significant decrease in core permeability. Under a displacement pressure of 40 MPa, the additional resistance accounts for as much as 72% of the total resistance, with high asphalt content and the extractive effect of CO₂ on crude oil components being important factors leading to core plugging. Therefore, in the field development process, the CO₂ enhanced oil recovery technology should be applied in a rational and tailored manner according to the properties of the field’s crude oil.

Results are given for a kinetic study of the synthesis of a new fullerene derivative containing a diterpene fragment obtained using HPLC and subsequent mathematical modelling. Kinetic and activation parameters were found for the cyclopropanation of fullerene using the Bingel procedure and a reaction mechanism was proposed. The optimal synthesis conditions were found to entail a slight excess of a chlorine‑containing cyclopropanation agent and carrying out the reaction at room temperature.

Horizontal well development of natural gas hydrate (NGH) can greatly improve gas production and make it cost-effective, which is one of the key technologies for the efficient development of NGH in the future. World widely, there is only limited experience in drilling horizontal wells into gas hydrate sediments, which lacks certain reference. In this paper, the practice of drilling horizontal wells into gas hydrate sediments, were analyzed the challenges. The challenges encountered when drilling horizontal wells into hydrate sediments were also analyzed. At least, the application of horizontal wells and complex well structure, which based on horizontal wells are analyzed. The advantages and disadvantages of several novel well structure are compared. This paper will contribute to the development of natural gas hydrate of our country.

In order to improve the accuracy of gravity anomaly data processing, this study utilizes multi-scale surface fitting techniques (MSSF) to separate the Bouguer gravity field into residual gravity fields and regional gravity fields at different depths. By sequentially stripping away layers, the residual gravity anomalies of the target layer are obtained as the data basis for subsequent gravity interpretation. This study selects appropriate parameters and establishes different lithology forward modeling templates based on actual geological data in the study area. The method is verified to accurately separate gravity anomalies generated by different density bodies, with accurate anomaly locations, complete shapes, and clear boundaries. It can also serve as a quantitative template for rock properties and provide theoretical references for practical cases. Additionally, the method exhibits high noise resistance, resolution, and accuracy. The practical application of the method is validated through microgravity monitoring data in carbonate reservoirs in western China and time-shifted microgravity monitoring data in tight sandstone reservoirs. The results demonstrate that the obtained residual gravity anomaly data of the target layer can effectively reflect the distribution of reservoir fluids.

The Longmaxi Formation in the Sichuan Basin is a hotspot formation for shale gas exploration. In this paper, taking the Longmaxi Formation shale in Yuxi area as an example, a large number of TOC tests, X-diffraction whole-rock mineral fraction tests, electron microscope observations, physical properties, gas content, and CT scanning experiments were carried out, which in turn analyzed the characteristics of the shale gas reservoir and the factors influencing the gas content. The results of the study show that there are seven types of shale facies developed in Yuxi area, which are organic-rich siliceous shale facies (I), organic-rich carbonate-siliceous shale facies (II), organic-rich clayey shale facies (III), organic-poor clayey shale facies (IV), organic-poor carbonate-siliceous shale facies (V), organic-poor siliceous shale facies (VI), and organic-poor siliceous-carbonate shale facies (VII). The microstructural characteristics of the shale reflect that it was disturbed by multiple environmental factors at the time of deposition, and the sources of brittle minerals include both terrestrial clasts and biogenic siliciclastics. The bottom 30 m shale of Longmaxi Formation has good physical properties and gas content, which is a high-quality target section for shale gas exploration and development. TOC, R_o, permeability, quartz content and clay mineral content all have a significant effect on shale gas content and are important control factors for shale gas content.

Oil shale, as an unconventional energy source, has attracted much attention in countries worldwide. The traditional way of extracting oil shale from the open pit is not only costly but also polluting to the environment. Sufficient understanding of the relationship between subsurface fractures and temperature fields is important for the extraction of oil shale and is of great significance for the actual in-situ extraction of oil shale. The study of fracture initiation and expansion in oil shale formations is based on the effect of fractures on convective heating efficiency in oil shale in situ conversion technology. In view of the objective situation that hydraulic fracturing can enhance the rate of the permeability and heating efficiency of oil shale formations, and hence the oil yield, the effect of single fractures with different fracture heights (2 mm, 4 mm, 8 mm) on the temperature field of oil shale; and the effect of multiple fractures (two, three and four fractures) on the temperature field of oil shale are investigated under convective heating methods.

The feasibility of obtaining a modified lignosulfonate reagent derived from acrylic and lignosulfonate components is examined. The completeness of the reaction yielding a modifier derived from acrylamide and citric acid to be used for subsequent dispersion in sodium lignosulfonate was monitored by HPLC. A comparative analysis of the surface tension data was carried out by the stalagmometric drop counting method. In order to study the effect of electrolytes on the surface activity of a complex reagent with acrylic and lignosulfonate components, the surface tension of aqueous solutions of NaCl and CaCl₂ of different concentrations was determined upon the introduction of from 0.1% to 2% reagent. The assessment of the adsorption activity was carried out by constructing an isotherm of surface tension at the liquid‑liquid interface under static conditions over time with constant reagent concentration. Feasibility was established for the use of this lignosulfonate reagent for effective reduction of the conditional viscosity of clay drilling mud at from 20°C to 180°C.

East Inner Mongolia region is rich in renewable energy and is an important power station. The aim of this study was to further enhance the development and utilization of wind power and photovoltaic in the East Inner Mongolia region, and help build a new type of power system in the region. Based on the research targets in Chifeng, Tongliao, Xing’an and Hulunbuir in the East Inner Mongolia region, Study of load characteristics, wind power and photovoltaic output characteristics and optimal ratios throughout the year, and study the scale and mode of operation of energy storage in the banner county seats. Research shows that wind power, photovoltaic monthly output during the year as a whole shows the law of “winter big summer small, spring big winter small”, applies. Taking into account the operating costs and the average standard deviation of slow regions, the optimal ratio of wind and photovoltaic power in Chifeng should be 4.7:1, in Tongliao 4.8:1 and in Hulunbuir and Xing’an 4.4:1; Compared with the adjustment of the before energy storage method, the combined power formed by the power storage of grid is relatively gentle, with a low peak valley difference, and the overall performance of the grid side storage is better than that of the supply side storage. Therefore, research on the ratio of wind and photovoltaic power and the energy storage analysis of these regions can effectively promote the development of power and accelerate the realization of strategic goals such as “dual carbon”, as well as providing a reference for the future planning of the East Inner Mongolia region power network.

Oil shale is an unconventional energy source with abundant reserves. However, the global oil shale resources have not been fully exploited. In-situ oil shale extraction technology based on electric heating has gradually become a research focus in this field. In this study, the construction of a numerical simulation model for the in-situ extraction of oil shale by electric heating and the results of the numerical simulation study are summarized. By summarizing the research progress and current status of numerical simulation of electrically heated in-situ oil shale extraction, the core issues, main challenges, progress made, and bottlenecks to be solved in the current numerical simulation research are analyzed.

Because of their small particle size, excellent stability, high temperature tolerance, and salt tolerance, polymer nanoparticles are attracting a lot of attention in low-permeability reservoirs. In this study, SiO2, acrylamide (AM), and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) were used to synthesize novel copolymer-grafted nano-silica particles (HPGN). HPGN’s overall performance in low-permeability reservoirs was evaluated. The results demonstrate that the viscosity of a 2000 mg/L HPGN solution at 50 °C is 75.8 mPa·s, with high stability under high temperature, high salt, and shear conditions. More notably, the displacement experiment proved that under the condition of 18450 mg/L, a 2000 mg/L HPGN solution enhanced the recovery rate by 21.89%. This research indicates that HPGN has great applicability potential in low-permeability reservoirs with high temperatures and salinities.