High-viscosity Oil Research Articles

Cleanup of oils and organic solvents from contaminated water by biomass-based aerogel with adjustable compression elasticity

Leakage of oils and organic solvents poses a significant threat to aquatic environments. Here, low-temperature carbonized aerogels with highly porous and anisotropic structures obtained only from biomass-derived materials were proposed to absorb polymorphic oils from contaminated water. Specifically, carbonized aerogels prepared at temperatures of 300 °C and 350 °C exhibited ultra-high absorption capacities (40‒125 g g−1) and oil-water separation efficiencies (> 99%) even in harsh environments, which were attributed to their exceptional properties, including high porosity, abundant macropores, excellent thermal stability, and hydrophobicity. Through citric acid crosslinking and low-temperature carbonization, the aerogels exhibited superior compression elasticity and could be cyclically utilized through simple extrusion while realizing the recovery of oils. Moreover, the outstanding photothermal conversion properties obtained through carbonization contributed to the high temperature and fluidity of the oils surrounding the aerogels, which is crucial for improving the absorption performance of high-viscosity oils. Such absorbent materials are used to separate crude oil from oil-water mixtures, which can achieve maximum absorption of 56 g g−1 and increase the absorption rate (from several days to 10 min) in a low-temperature (4 °C) seawater environment.

Research on a fluorine-containing asphaltene dispersant and its application in improving the fluidity of heavy oil

The high viscosity characteristics of heavy oil make it difficult to extract, transport and process. Therefore, enhancing the fluidity of heavy oil can effectively improve the economic benefits of heavy oil resource development. Aggregation and precipitation of asphaltenes are the main causes of high viscosity of heavy oil. Asphaltene molecules are able to self-associate by intermolecular forces such as hydrogen bonding and π-π interactions, resulting in the formation of supramolecular aggregates with large particle size, leading to the increasing of viscosity of heavy oil. Fluorine is the most electronegative element and has a strong ability to form hydrogen bonds. This is due to the special role of the element fluorine, including high electronegativity and small atomic radius. In this study, the fluorine-containing copolymer was synthesized and used to disperse asphaltenes. This copolymer was also used for viscosity reduction on heavy oil in a block in Xinjiang, and the viscosity reduction rate (VRR) reached 70.25% at 600 ppm. Possible mechanism of asphaltene dispersion was proposed by fluorescence microscopy, X-ray diffractometry (XRD), scanning electron microscope (SEM), atomic force microscope (AFM) and transmission electron microscopy (TEM). The mechanism of interaction between copolymer and asphaltene by hydrogen bonds was further analyzed by infrared spectroscopy.

The effect of disperse phase viscosity in the emulsification of a semi-dairy beverage–combining emulsification experiments and numerical single drop breakup simulations

Due to the rise in the demand for semi-dairy beverages (vegetable fat in a de-fatted dairy matrix) as well as for fully plant-based formulations, there is a growing interest in better understanding how emulsification processes are influenced by raw material choices. Semi-dairy beverages, for example, utilize a wide variety of vegetable oils in their formulation. This contribution combines traditional emulsification experiments with high-resolution numerical drop breakup simulations to improve the understanding of how oil viscosity influences the emulsification process. It is concluded that the experimentally observed increase in drop diameter with oil viscosity is well predicted by the viscosity-corrected Kolmogorov Hinze theory. The numerical simulations are able to reproduce this trend and allow further insight into breakup mechanism; suggesting that it is the prolonging of the deformation phase that make more viscous oils more challenging to homogenize. From a beverage processing perspective, the homogenizing pressure (and energy cost) necessary to achieve the same physical stability needs to be 73% higher if using a typical high-viscosity vegetable oil than if using a typical low viscosity vegetable oil.

An experimental and modeling investigation of the behaviors of solution in fluoropolymers hollow fiber membranes (HFMs)

This work focuses on the mass transfer in hydrophobic polyvinylidene fluoride (PVDF) and poly (tetrafluoroethylene-co-hexafluoropropylene) (FEP) hollow fiber membranes, using a combination of experiments and computational fluid dynamics (CFD) model. Our experimental design considered a wider range of viscosity and surface tension for the feed solution (kerosene, lubricating oil and water), a larger span of operation temperature (25–85 °C), and longer usage time (8 h). The membranes were characterized for the permeability, morphologies, pore size distribution, porosity, water contact angle (WCA), roughness, differential scanning calorimetry (DSC) and tensile property. Numerical simulations of two-phase and single-phase flow in micron membrane channels were performed for several selected groups to assist interpretations of the experiments and to examine the effects of wettability, viscosity and pore size on the mass transfer process. The simulations base on the OpenFOAM-model agree well with the experimental results. Collectively, this study provides new insights regarding mass transfer in membrane channels and reference data for the use of fluoropolymers membranes for non-aqueous solution, especially high viscosity oil.

Construction of Janus silicon carbide membranes with asymmetric wettability for enhanced antifouling in water-in-oil emulsification process

Given that the membrane emulsification process involves the interaction between the membrane surfaces and two different phases (i.e., oil and water), separately manipulating the wettability of each surface would be crucial to achieve the high emulsification efficiency. Herein, the Janus silicon carbide (SiC) membranes were designed and prepared by using an emerging reactive sintering method and the subsequent chemical grafting modification on one of the hydrophilic surfaces. The surface wettability was selectively controlled by using hexadecyltrimethoxysilane (HDTMS) and 1H, 1H, 2H, 2H-perfluorooctyltrichlorosilane (FOTS) as the hydrophobic or amphiphobic modifiers, respectively. Meanwhile, the modified side of Janus SiC membranes showed super-hydrophobicity under oil. It was found that the hydrophobic surface can inhibit the spread of water on membrane surface and the oleophobic surface can reduce the pollution of the membrane, which both affected the membrane emulsification performance. The water-in-oil (W/O) emulsions with mean water droplet size of 1.26–1.57 μm can be prepared using amphiphobic-hydrophilic Janus membranes at a high emulsification flux (1910 L·m−2·h−1). Importantly, the pure water permeance only declined 15.6% of the original value after three times of membrane emulsification. Moreover, the polluted membranes can be easily and effectively regenerated by ultrasonic cleaning in ethanol with a flux recovery ratio of 95.8%. Therefore, the amphiphobic Janus SiC membranes showing improved anti-fouling ability can be effectively utilized in the emulsification of high-viscosity oil.

Физико-химическая характеристика образцов нефти Тагульского месторождения

The article presents the data of a comprehensive study of three samples of high-viscosity borehole oil of the Tagulskoye field. Using the instrumentation and methodological base of JSC «MidVolgaNIINP», information was obtained on the composition and properties of samples of high-viscosity oil (HVO) after preliminary dehydration and desalination, as well as oil distillate fractions and residues from distillation obtained in laboratory conditions according to GOST 11011, ASTM D 2892/5236. In addition, it is shown that the objects of the study have valuable properties: a low content of total sulfur, a low content of paraffins and a fairly low pour point for heavy oils. The authors have proposed options for further use of the studied objects. In general, valuable basic information has been obtained for the long-term planning of production and the choice of options for the use /processing of unique raw materials.

The P-µ-T Cubic Equation of Viscosity for Reservoir Oils

Summary Oil recovery simulation sensitivity increases with heavier oils for the existing viscosity models, driving into higher levels of difficulty when fitting viscosity data for rising oil heaviness, particularly below the saturation pressure. Keeping in view the similarity of trends of viscosity and density with isothermal pressures for reservoir oils, the P-μ-T cubic viscosity model, which was developed for pure hydrocarbon components, was extended to reservoir oils. Two parameters in the P-μ-T cubic viscosity model for mixtures with pure and pseudocomponents are identified for adjusting the viscosity data fitting: Kc for controlling the viscosity gradient with pressure and the “ε” shifting trends for increasing viscosity direction. These two parameters are treated as the adjustable parameters required for fitting the viscosity data. A total of 129 reservoir oils from different sources are used to validate the reliability of the P-μ-T viscosity model. The default model (where ε and Kc are 1 and 45, respectively), extended to 71 light oils, resulted in 31% of average absolute relative deviation (AARD) in viscosity prediction. However, separate adjusted parameters are obtained per oil for more accurate viscosity data fitting. Application of the model in this work results in (post-fitting) AARD% of 2.86% average for 36 low-viscosity oil data, 5.68% for 9 high-viscosity oil data, 9% for five oil blends, and 4.11% for bitumen blends. The model gives an AARD of 3.06% in the undersaturated region and 3.79% in the saturated region for the oil considered. The model predicts better the viscosity above saturation pressure for low-viscosity oils and below saturation pressure for high-viscosity oils. A comparative analysis of the P-μ-T cubic viscosity model vs. other models demonstrates its ability to successfully capture viscosity trends of oil and blends in all viscosity ranges. For simplicity, the P-μ-T cubic viscosity model is proposed with only two optimizing parameters even though using a third parameter improves the matching in heavy oils.

Experimental study of the features of filtration of non-Newtonian oils in a porous medium

The current state of development of deposits with high-viscosity oils is characterized by a low value of the achieved oil recovery with a high water cut in the produced wells. However, ways to improve the implemented development systems in order to increase the recovery factor in conditions of high water cut in well production, especially in the late stage of operation requires further research. Therefore, this research intended to investigate features of filtration of non-Newtonian oils in a porous medium. Oil fields with a complex geological structure have been discovered in many oil and gas regions of the world. These fields are characterized by a small oil-saturated thickness of the reservoirs, low reservoir properties, high viscosity of reservoir oil and heterogeneity of productive horizons. To study the filtration process, a specially designed installation was used. Clearly, the main elements are a column (core holder) with a water jacket, an oil tank, a thermostat and a high-pressure air tank (compressor). A research experiment was undertaken in two oil fields, which are X and Y. The results of physicochemical properties of oil field X showed that the density was 0.878g/cm3, followed by sulfur content (1.51%), pitches (21.89), asphaltenes was 4.19, and paraffin was 5.18.

Analysis of the degree of influence of geological and technological factors on the initial flow rates of wells commissioned after their downtime

The results of statistical processing of data from 97 wells put into re-operation, after their long downtime due to flooding, are presented. In which, depending on the geological and physical conditions and the state of development of oil deposits, different results are obtained. With an average initial oil flow rate of 1.12 tons/day in reservoir-vaulted deposits with low-viscosity oil in the Fergana oil and gas region - 0.5 tons/day, in reservoir-arch deposits with high-viscosity oil in the Surkhandarya oil and gas region - 0.97 tons/day, in sub-gas deposits of the Bukhara-Khiva region - 2.5 tons/day. By assessing the informativeness of geological, physical and technological factors using the Kulbak method, the degree of their influence on the initial oil flow rate of wells after their re-commissioning was established. Taking into account the degree of influence of the factors considered, it is recommended to put into re-operation wells located in the arched part of the reservoir, having the highest effective oil-saturated thicknesses, in areas with a low oil recovery factor and a lower degree of reduction in initial reservoir pressure, as well as watered in a short period of operation.

Advances in special wettable materials for adsorption separation of high-viscosity crude oil/water mixtures.

Effective separation of highly viscous crude oil/water mixtures remains a worldwide challenge. Employing special wettable materials with adsorptive properties as an emerging separation strategy has attracted extensive attention in the treatment of crude oil spillage. Such a separation technique combines excellent wettability materials and their adsorption performance to achieve energy efficient removal or recovery of high viscosity crude oil. Particularly, special wettable adsorption materials with thermal properties provide novel ideas and directions for the construction of rapid, green, economic and all-weather crude oil/water adsorption separation materials. Negatively, the high viscosity of crude oil makes most special wettable adsorption separation materials and surfaces extremely susceptible to adhesion and contamination in practical applications, leading to rapid functional failure. Moreover, such an adsorption separation strategy towards high-viscosity crude oil/water mixture separation has rarely been summarized. Consequently, there are still some potential challenges in separation selectivity and adsorption capacity of special wettable adsorption separation materials which urgently need to be summarized to guide the future development. In this review, the special wettability theories and construction principles of adsorption separation materials are first introduced. Then, the composition and classification of crude oil/water mixtures, particularly focusing on enhancing the separation selectivity and adsorption capacity of adsorption separation materials, are comprehensively and systematically discussed via regulating surface wettability, designing pore structures and reducing crude oil viscosity. Meanwhile, the separation mechanisms, construction ideas, fabrication strategies, separation performances, practical applications, and the advantages and disadvantages of special wettable adsorption separation materials are also analyzed. Finally, the challenges and future prospects for adsorption separation of high-viscosity crude oil/water mixtures are expounded.

Adjustment of infill in transition zone to improve oilfield productivity

Affected by the high viscosity of crude oil, the large injection-production well spacing, the poor injection condition, and the low oil recovery rate, the overall development effect of transition zone is poor, besides, the low produced degree and the poor utilization of thin oil layer makes transition zone have some potential excavation. Under the condition that the current conventional measures to improve block development are not clear, it is necessary to further optimize the injection-production system. Based on the principle of “Well pattern rules, Well spacing optimization, Injection-production perfecting, Facilitation of adjustment”, layer combination is thus optimized. This paper analyzes the effect of encryption adjustment and tracking adjustment.

Напрямки оптимізації розвідки і розроблення нафтових родовищ Західного Причорномор’я України

The southern part of the Dobrogea Foredeep is located in the southwestern regions of Ukraine within the Odesa region. Here, on the territory of the uplifted Bilolissya block, the East Sarata, Zhovtyjar, Saryjar, Zarichna oil accumulations are located in the chemogenic-carbonate layer of the Middle and Upper Devonian. The deposits are confined to limestones and dolomites with secondary fractured-cavernous-porous reservoirs. They lie at depths of 2500–3200 m. During the test of two dozen wells, the filtrate of the drilling fluid with a small amount of oil was received with the estimated flow rates of several tons per day. The rise of the oil level in the wells was quickly stopped, the hydrodynamic connection of the wells with the productive formations was lost. The use of today's known methods of intensification of the flow of hydrocarbon fluids did not lead to positive results. According to the research of microphotographs of reservoir rocks, it is proved that the largest voids of reservoir rocks are filled with immobile bitumen, while the smaller cavities contain mobile oil. Immobile bitumen fills main channels and blocks communication between rock cavities. This is the main reason for the absence of industrial inflows of oil to the wells. Another important reason is the low filtering properties of the collectors. Most of them have a permeability of less than 0.01∙μD. Other reasons for the failure of the industrial development of oil deposits are the high dynamic viscosity of oil due to the high content of asphaltenes, silicagel resins, paraffins, the low energy potential of oil deposits due to their degassing during the long geological time, as well as the lack of hydrodynamic connection of oil deposits with natural water pressure systems. We assume that the Middle and Upper Devonian oil fields of the Western Fore-Black Sea area are most likely mainly bituminous. Given the significant depths of the deposits, their industrial development is technically impossible today. Therefore, it is impractical to plan further scientific research on the mentioned complex. Instead, research should be reoriented to the Silurian terrigenous-carbonate complex and the Lower Devonian terrigenous complex, which are hydrodynamically more closed and in which non-degassed hydrocarbon accumulations can be preserved.

Математическое моделирование макрокинетики термолиза сложных углеводородных систем

Stochastic mathematical models of thermolysis kinetics of complex oil-like hydrocarbon systems using mathematical statistics and the theory of random processes are considered. Mathematical modeling shows that the thermolysis process is collective,non-ergodic and non-stationary. The criteria for which hydrocarbon systems obey the kinetic laws of the first order and Abraham are established. Using the example of thermolysis of high-viscosity Alshacha oil, it is shown that the kinetics of the release of gaseous products of thermolysis are better described by models of stationary kinetics, and the models of the release of residues and distillates by models of non-stationary kinetics. The established regularities can be used in modeling thermal and thermocanalytic processes of petrochemistry and oil refining.

Development of the water-saving technology for refining high-viscosity watered petroleum in oilfield

The article presents research on demulsifiers for oil dehydration in order to increase the conservation of water resources by introducing an additional source. The laboratory experimental works on selection of highly effective demulsifier were carried out. The application of water-saving technology which provided the necessary technological and economic effect was proposed. The analysis of laboratory researches on improvement of the method of dehydration of high-viscosity watered oil showed that under optimally selected conditions, namely: concentration of 75 g/t, temperature of 70 degrees and long settling time, the most effective demulsifier from all the reagents used in the tests was the reagent number 2 which showed the lowest residual water content and satisfied the final criteria both in economic terms and in quality of separation of water from oil without changing its initial structure. The water extraction according to the improved oil dehydration technology increased from 10% to 60%.

Polymer Composition for Reducing Permeability in a Fractured High-Viscosity Oil Reservoir

Polymer Composition for Reducing Permeability in a Fractured High-Viscosity Oil Reservoir

ЭКОНОМИЧЕСКИЕ ЭФФЕКТЫ ВНЕДРЕНИЯ ЭЛЕКТРОМАГНИТНЫХ ТЕХНОЛОГИЙ В НЕФТЕДОБЫВАЮЩУЮ ОТРАСЛЬ РЕСПУБЛИКИ БАШКОРТОСТАН

The article substantiates the importance of the implementation of the project for the introduction of methods for the development of oil fields based on the use of electromagnetic field energy to solve the problems of socio-economic development of Bashkortostan Republic in the conditions of the current state of the oil industry in the region. The author identifies the dependence of the socio-economic development of the republic on the state of the oil industry, identifies its key problematic points: low oil recoverability in the fields, as well as a high level of waterlogging of the extracted oil. The possibilities of covering the deposits of Bashkortostan Republic, suitable for the development of residual oil reserves, with electromagnetic technologies are determined. The conclusion is formulated about the expediency of introducing electromagnetic technologies in the deposits of Bashkortostan Republic in order to support the socio-economic development of the region. The results of the work can be used in the analysis of the prospects of regions with the predominant development of the oil production and refining complex. Further research may be devoted to assessing the immediate and delayed effects of the application of the considered and other innovative technologies in regions with a developed mining infrastructure. The study made it possible to formulate a number of conclusions: 1. The oil industry in Bashkortostan Republic is key for the socio-economic development of the region with various results of functioning: employment coverage, tax, investment aspects, etc. In addition, the oil-producing complex has a significant indirect impact on the socio-economic development. 2. Systematic reduction of oil production in the region leads to underutilization of its refining capacity, which is not compensated by oil coming from outside. The mining technologies currently used will not allow it to maintain an acceptable level in the future. The introduction of electromagnetic technology in depleted fields and, especially, in deposits of high-viscosity oil will allow to obtain significant volumes of oil in the near future. 3. The key effects of the introduction of electromagnetic oil production technologies for the socio-economic development of Bashkortostan Republic are the creation of jobs, expansion of the tax base, additional dividend payments and additional loading of existing refining capacities.

Некаталитические технологии переработки нефтяных остатков и тяжелых нефтей

The depletion of recoverable reserves of crude oil in the world requires a qualified approach to the problem of processing oil residues, the share of which increases with the involvement in the turnover of high-viscosity oils and natural bitumen with high density, viscosity and low yield of light fractions. The Institute of Petrochemical Processing has traditionally been engagedin the development of the problem of non-catalytic processing of heavy oil raw materials since the beginning of its existence. The work summarizes the developments Institute of Petrochemical Processing in this field, carried out for almost 20 years, part of which it has already received industrial implementation, and the rest is ready for implementation.

Analysis of the hydrodynamic modeling market under the environmental conservation concept

The paper presents a comprehensive analysis of the global software market for modeling technological processes in the field of oil and gas based on data from independent analytical agencies. The work covers various aspects of the industry through a study of key competitors. The paper also provides a better understanding of the meaning of modeling software implementation. The assessment of the potential of the domestic market (TAM-SAM-SOM method) was carried out and the expediency of introducing Russian software for hydrodynamic modeling of high-viscosity oil was substantiated.

STUDY OF THE EFFICIENCY OF OIL DISPLACEMENT PROCESS BY POLYMERS OF DIFFERENT GRADES

Currently, a large number of fields with high-viscosity oil are being developed. Increasing the degree of oil recovery from the subsoil of developed fields using effective methods of active influence is an important scientific and technical task for employees of oil producing enterprises. One of the most effective and promising methods for stabilizing oil production is physical and chemical technologies based on the injection of polymer compositions. Therefore, the authors of the article pursue the goal - to investigate the effectiveness of the use of polymer compositions for further recommendation for use in fields with high-viscosity oils and formations containing hard-to-recover reserves. The article provides an analysis of the results of the study of polymers, namely GL-50 and R-1 on rock samples of various well depths. In this regard, an experiment was carried out to displace oil with various displacing reagents. During the oil displacement experiment with various displacement reagents, the water saturation of the sample and the displacement efficiency were determined. Particular attention is paid to the rate of advancement of the flow of polymers and the propagation of molecules through pores of different diameters. The main goal of this experiment was to determine a more effective polymer for enhanced oil recovery. Comparison of oil displacement efficiency at the stages of polymer injection is given. In the course of the study, the results of determining the displacement coefficients of GL-50 and R-1 polymers were obtained. From the results obtained, it can be assumed that polymer grades have a significant impact on the degree of efficiency of the oil displacement process.

Megareservoirs of hydrocarbons are accumulation of giant by oil and gas deposits

The priority direction for the development of the oil and gas complex of Russia is the search for and development of giant oil and gas fields in terms of reserves, confined to natural megareservoirs of sedimentary strata. The article considers: conventional megareservoirs of oil and gas bearing basins (OGB), in which giant and unique oil and gas deposits are accumulated (on the example of the Pokur suite of Western Siberia); megareservoirs associated with commercial vanadium-bearing heavy oils and natural bitumen in unconventional reservoirs: bituminous sands in the province of Alberta (Western Canadian OGB), Permian natural bitumen in the Volga-Ural (Republic of Tatarstan) OGB, Cambrian bitumen in Eastern Siberia; megareservoirs of unconventional low-pore shale reservoirs. These accumulations of hydrocarbons (HC) can be considered megareservoirs: due to their vast areas and high saturation with kerogen. It is shown that accumulations of hydrocarbons in megareservoirs of shale formations, high-viscosity oils and natural bitumens accumulate ore concentrations of industrially valuable metals; an integrated approach to field development is economically in demand in the present conditions. Keywords: megareservoirs; collector; gigantic accumulations; oil and gas bearing basins; trace elements; natural bitumen; shale formations.