In this paper, the effect of natural trass rock as a pozzolanic mineral additive on the rheological, physicochemical and mechanical properties of class G Portland cement, widely used in oil well drilling and workover operations, was studied. Trass, obtained from the Koroglu deposit in the Lesser Caucasus region of Azerbaijan, was incorporated into the cement system at 5, 10 and 15 wt.% replacement levels. Its chemical and mineralogical properties were determined using X-ray fluorescence (XRF) and X-ray diffraction (XRD) analyses. Experimental results show that the addition of trass significantly improves the performance of the mixture by increasing slurry fluidity and reducing the plastic viscosity, while simultaneously increasing stability under dynamic conditions. The rheological stability of the cement slurry was improved by approximately 7-9 % compared to pure cement systems. In addition, the compressive strength increased significantly, indicating improved structural integrity. These effects are mainly attributed to pozzolanic reactions between reactive amorphous silica (SiO₂) and alumina (Al₂O₃) in the trawl and calcium hydroxide formed during cement hydration, and the interaction promotes the formation of additional calcium silicate hydrate (C–S–H), resulting in a denser and finer microstructure. In addition, the modified cement systems demonstrated increased durability, including higher resistance to thermal cycling and aggressive formation fluids such as saline waters and CO₂-rich environments. İn this study use of natural trass can help reduce the carbon footprint associated with traditional cement systems by partially replacing the clinker content. Keywords: oil well cementing; class G Portland cement; natural trass; rheology; pozzolanic reaction; zonal isolation.
The presented article reviews and evaluates contemporary engineering solutions aimed at optimizing the operating modes of gas-lift wells in modern oil field operations. Within this study, the estimation of the current performance and energy efficiency of gas-lift systems using real-time field data is considered of particular importance for sustainable production. To achieve this, efficiency factor (η) of the lifting system was meticulously calculated for selected wells where a reliable database of operational parameters was available. For the analytical part of this research, the specialized methodology developed by A. S. Alasgarov was utilized as the primary evaluative framework. To investigate operational efficiency based on actual surface parameters, and to identify candidates for production enhancement - specifically those where targeted technological interventions could yield positive results – a detailed joint analysis of the aforementioned well parameters was conducted. Based on extensive field data, the individual operating modes of several gas-lift wells were investigated under various conditions. The results revealed that in five specific wells characterized by exceptionally high water cut levels, the overall lifting efficiency decreased drastically, ranging from 44.5 to 82 %. To mitigate these losses and restore productivity, it is recommended that the effectiveness of bottomhole and reservoir stimulation methods against water cut be further evaluated for the respective wells. Finally, to enhance operational efficiency, the optimization of wells with similar fluid and pressure parameters was addressed by categorizing them into distinct diagnostic groups based on multi-variable criteria. Keywords: gas lift operation method; optimization of operation mode; gas injection rate; well efficiency; similarity criterion.
A new experimental finding regarding the violation of Darcy's law during the flow of liquids in a microcrack with an opening less than its critical value h
The investigation of the rheological properties and demulsification behavior of oil–water emulsions formed in oil gathering systems is of considerable importance for addressing technological challenges associated with crude oil treatment, dehydration, and transportation. In this study, the rheological behavior of oil–water emulsions containing 0–90 % formation water and the performance of a newly developed demulsifier composition were experimentally evaluated under laboratory conditions. The results demonstrated that the effective viscosity and shear stress of the emulsions are strongly dependent on water content. An increase in the volumetric fraction of water enhanced droplet–droplet interactions, promoted structural strengthening of the system, and increased resistance to flow. Rheological measurements confirmed the non-Newtonian behavior of the investigated emulsions and revealed a significant increase in viscosity with increasing dispersed phase concentration. To intensify the demulsification process, a novel formulation based on polypropylene glycol, polyethylene polyamine, sodium naphthenate, and methanol was developed. Laboratory experiments showed that the proposed composition provided a water separation efficiency of 77–81 % in emulsions containing 60% water. This effect is attributed to the reduction in the stability of the interfacial layer and the acceleration of water droplet coalescence. It was also found that freshly prepared emulsions were demulsified more readily than emulsions stored for five days, while increasing the demulsifier dosage improved separation efficiency only up to an optimum level. The obtained results indicate a clear relationship between the structural-rheological characteristics of emulsions and their demulsification efficiency, providing a scientific basis for improving the technological efficiency and operational reliability of crude oil dehydration processes. Keywords: oil–water emulsion; rheological properties; gathering system; demulsifier composition; emulsion breakdown; flowability.
The effect of metal nanoparticles on the interfacial activity of demulsifiers at the kerosene–distilled water interface was investigated using aluminum (50–70 nm), iron (40–60 nm), and copper (40–60 nm) nanoparticles. The study aimed to evaluate the influence of metallic nanoparticles on the performance of demulsifiers used in crude oil dehydration and desalting processes and to identify the optimum nanoparticle concentration for the development of highly efficient demulsifier formulations. Four commercially available water-soluble demulsifiers—Alkan DE-202B, Alkan DE-318A, ND-12, and Disolvan 4411—commonly applied in the treatment of water-in-oil emulsions containing salts and suspended solids were examined. Demulsifier solutions were prepared at concentrations of 0.01–0.05 wt.%, while nanoparticle concentrations ranged from 0.0005 to 0.01 wt.%. The results demonstrated that the incorporation of nanoparticles at concentrations of 0.001–0.005 wt.% reduced the interfacial tension of the demulsifier solutions by up to 60%, indicating a significant enhancement in interfacial activity. However, a slight increase in interfacial tension was observed at higher nanoparticle concentrations (0.005–0.01 wt.%), suggesting the existence of an optimum dosage. FTIR analysis confirmed that the incorporation of aluminum nanoparticles into the polyether matrix (Laprol-4202) did not alter its molecular structure. In addition, the viscosity of the commercial demulsifier Alkan DE-318A increased slightly from 69.0 to 74.0 mPa·s after the addition of 0.005 wt.% Al nanoparticles. The efficiency of the nanoparticle-modified demulsifiers was further evaluated using crude oil emulsions from the Buzovna and Gala oil fields. The modified formulations exhibited superior demulsification performance, achieving deeper dehydration of highly stable crude oil emulsions than the corresponding unmodified commercial demulsifiers. Keywords: demulsifier; Alkan DE-202B; Alkan DE-318A; Disolvan 4411; ND-12; aluminum nanoparticles; copper nanoparticles; iron nanoparticles; interfacial tension; demulsification; crude oil emulsion.
The article explores the development directions of Azerbaijan’s electric power system, considering the efficient use of alternative energy sources and their impact on the environment. Increasing geopolitical instability, environmental challenges, and growing energy demand are strengthening the importance of energy security and require diversification of generation sources. In this regard, Azerbaijan is gradually adapting its national energy strategy to international trends by expanding the use of renewable energy sources and strengthening regional cooperation. Special attention is given to the strategic initiative aimed at creating the «Green Energy Corridor» Caspian–Black Sea–Europe, designed for the export of environmentally friendly electricity produced based on the wind potential of the Caspian Sea. This project contributes to the country’s integration into the international energy system and diversifies exports by reducing dependence on traditional oil and gas resources. The study analyzes statistical data on electricity generation in the country, including the growth dynamics of solar, wind, and hydropower production. According to estimates, Azerbaijan possesses significant technical potential for renewable energy both onshore and offshore, creating favorable conditions for large-scale green energy projects. The technological principles of wind, solar, and hydroelectric power plants are also discussed using simplified mathematical models describing their operational mechanisms. Additionally, the relationship between industrial production and economic growth is analyzed, confirming the strategic role of renewable energy development in reducing production costs and enhancing economic competitiveness. Overall, the results indicate substantial potential for sustainable development of the national energy system. Keywords: alternative energy sources; environment; electricity generation; renewable energy; hydropower; solar power; wind power.
The reliability and sealing performance of casing strings is one of the most significant scientific and engineering difficulties associated with drilling oil and gas wells. Important parts that guarantee annular space sealing and safe support for casing strings inside the well are wedge-type casing hangers. The advancement of the oil and gas sector has coincided with the development of wedge-type casing hangers. Many changes have been implemented in recent years to enhance their operational safety, performance, and dependability. Nevertheless, increasing the dependability and sealing effectiveness of wedge-type casing hangers continues to be a significant problem for the oil and gas sector as well as producers of oilfield equipment, despite intensive research and engineering efforts. The operating principle of wedge-type casing hangers is based on converting an axial force into a clamping force that securely holds the casing or another structural element in place. Although the design is relatively simple, the system is susceptible to wear, reduced clamping force, and other failure mechanisms, making a comprehensive approach to reliability assessment essential. Achieving high reliability of wedge-type casing hangers largely depends on several key parameters, including the wedge angle, the coefficient of friction, and the applied loads. Under real operating conditions, these parameters cannot be determined with complete accuracy. Therefore, selecting the optimal design and operating conditions requires a method capable of handling uncertainty, such as fuzzy logic. Based on this, the present study is aimed at determining the optimal operating parameters of wedge-type casing hangers using the principles of fuzzy logic. Keywords: wedge-type casing hanger; wellhead; fuzzy logic theory; wedge angle; coefficient of friction; reliability; casing string.
A multifunctional corrosion inhibitor–biocide composition was developed using fatty acid imidazolines synthesized from soapstock, a waste by-product of vegetable oil refining. The imidazoline compounds were obtained via a one-step reaction between soapstock and aminoethylethanolamine (AEEA) at 170–220 °C for 8 h. The chemical structure of the synthesized imidazolines was characterized by FTIR and ¹H NMR spectroscopy, which verified the formation of the imidazoline ring as well as the presence of long hydrocarbon chains derived from fatty acids. The ¹H NMR results confirmed the synthesis of imidazoline by the presence of equivalent triplet signals of the methylene groups in the imidazoline ring at δ = 3.28 and 3.70 ppm. The probable mechanism for the one-step synthesis of imidazolines from soapstock has been proposed. The corrosion inhibition performance of synthesized composition was evaluated in a CO2-saturated 3.5 wt.% NaCl solution using linear polarization resistance (LPR) measurements. The results showed a significant reduction in corrosion rate and metal loss compared to the blank solution. Inhibition efficiency increased with concentration and reached an optimum value at 100 ppm, achieving approximately 84–85 % protection efficiency. Microbiological tests against sulfate-reducing bacteria (SRB) demonstrated strong biocidal activity, with inhibition efficiency 100% at 80-100 ppm. This indicates that the synthesized composition, at its optimal concentration, completely eliminates microorganisms responsible for microbiologically influenced corrosion (MIC). Overall, the developed inhibitor-biocide composition exhibits dual functionality as both a corrosion inhibitor and biocide, effectively mitigating CO2 corrosion and MIC. Keywords: aminoethylethanolamine; imidazoline; CO2 corrosion; potentiostat; electrochemical measurements; biocide.
In this article, the authors propose a composition for a polymer-containing drilling fluid and ways to reduce its loss during drilling of oil and gas wells. Theoretical aspects of drilling fluid loss are presented, including the characteristics and causes of fluid absorption by the rock. The main problems of drilling fluid loss associated with the instability of clay-argillite rocks of the South Torgay basin in Kazakhstan are described. The polymer-containing drilling fluid was obtained by adding polyacrylonitrile modified with fatty acid salts, which are a saponified fraction of the tar from the distillation of cottonseed oil fatty acids. The results of spectral studies of the modified polymer reagent polyacrylonitrile are provided. The authors present the results of studies on the effects of modified polyacrylonitrile, as well as crushed cotton stalks in various ratios on the properties of drilling fluid. These studies were conducted to reduce the rate of fluid loss through the borehole crust. Based on these conducted studies,on the effect of modified polyacrylonitrile and crushed cotton stalks on the rheological properties of the drilling fluid. A diagram of an experimental setup for determining the rate of drilling fluid passage through rock is presented, as well as when adding tar-modified polyacrylonitrile to the fluid. Existing methods for reducing drilling fluid loss are analyzed, and recommendations for implementation of this composition are proposed to increase the efficiency of the drilling process in complicated geological conditions. Keywords: drilling; well; rock; loss (absorption); oil; gas; drilling fluid; tar; polyacrylonitrile; modification; spectroscopy.
The article examines contemporary solutions for optimizing gas-lift well operation modes. By analyzing flow conditions and the upward gas flow equation, the process of liquid displacement by gas within the annular space toward the tubing shoe was evaluated. Based on wellhead parameters and the downward gas flow equation, gas pressure at the shoe of the second-string tubing in a concentric dual-string configuration was theoretically determined. Furthermore, the gas injection velocity (υ ) at the shoe zone was calculated using a derived formula corresponding to the pressure at that depth. The correlation between gas velocity, liquid production, and gas injection rates was investigated. For this purpose, Q = f (V) and υ = f (V) relationships were established for five gas-lift wells based on field data and wellhead parameters. Results revealed a specific correlation between gas velocity at the tubing shoe and production rate, indicating that injection velocity at the entry point can effectively characterize the well's operation mode. To determine the optimal operation mode for gas-lift wells, Q = f (V) and υ = f (V) curves were plotted simultaneously. It was observed that the optimal mode determined from both graphs aligns at approximately the same point. Based on the results, it is concluded that the dependence of the liquid production rate on the operating gas injection rate can be substituted by the dependence of gas injection velocity on the gas injection rate for gas-lift wells. Keywords: gas-lift wells; operating mode; tubing shoe; gas injection rate; gas injection velocity.
This article presents a comprehensive study on the development and optimization of a multi-channel Laval nozzle-based sand separator designed for natural gas streams under high-pressure conditions (up to 5.0 MPa). A comprehensive study on the design and optimization of a sand separator has been presented, taking into account changes in flow parameters under conditions where the high-pressure (up to 5.0 MPa) gas flow rate decreases from 5 million m³/day to 0.5 million m³/day, and an adaptive system with three inlet pipes has been proposed. Calculations show that when the Mach number is maintained within the range of 1.1–1.25, the separation efficiency remains within the range of 90–95%. The study includes hydrodynamic modeling, flow regime analysis, and a parametric evaluation of nozzle dimensions to ensure stable supersonic separation at various gas flow velocities. A hybrid operational concept featuring three inlet lines and variable nozzle combinations is proposed enabling flexible operation from maximum to minimum flow conditions. Computational modeling and correlations confirm the technical feasibility of the design for enhancing sand capture efficiency under high-density conditions. CFD modeling has been presented at a conceptual level in this work and has been substantiated for future verification. Keywords: natural gas separation; sand trap; supersonic flow; high-pressure gas; flow optimization; computational modeling.
Based on an integrated analysis of recent seismic surveys and drilling data conducted in the southeastern part of the Terek–Caspian Depression, within the Caspian coastal Guba oil and gas region and the Northern Absheron uplift zone, which is considered one of the main tectonic elements of the Absheron Archipelago, seismic horizons corresponding to the Lower Jurassic, Middle Jurassic, Lower Cretaceous, and Upper Cretaceous surfaces were correlated on dynamic depth sections of regional seismic profiles oriented in different directions and reflecting the distribution patterns of Mesozoic deposits within the geological section. Using seismic sections reinterpreted through modern approaches, structural maps of the Mesozoic horizons were compiled and geologically interpreted. The structural framework of the Mesozoic complex was refined, and several structural uplifts were identified. The lithostratigraphic characteristics and depositional environments of the strata within the study area and adjacent zones were investigated, and the distribution patterns of these deposits were determined. Organic-rich and reefal limestones formed under shallow-marine conditions on the southeastern flank of the Greater Caucasus are considered favorable reservoirs for hydrocarbon accumulation. Their paleotectonic and paleogeographic settings were also examined. Analysis of the reconstructed paleoseismogeological sections indicates that sedimentation in the Khudat area occurred under relatively shallow-marine conditions and at higher sedimentation rates, whereas south of the Aghzibirchala uplift sedimentation took place in a deeper-marine environment. During the Middle Jurassic, the Aghzibirchala and Khachmaz uplifts, which originated in the Early Jurassic, continued their development. The timing of structural formation and the hydrocarbon potential of these structures were also assessed. Keywords: seismic exploration; Mesozoic complex; sedimentation; hydrocarbon potential; tectonic structure; paleotectonic and paleogeographic conditions; oil and gas potential.
In recent years, integrated geophysical exploration studies, incorporating seismic and gravimetric methods, have been implemented in the Kura Depression of Azerbaijan. Currently, there are broad opportunities available for conducting these research studies. Modern 2D and 3D seismic acquisition techniques that meet current industry standards, advanced gravimetric instruments (e.g., Scintrex CG-6 Autograv), and newly developed data processing and interpretation methods enable these challenges to be addressed at a high technical level. The obtained results indicate that the hydrocarbon potential of many fields has either been insufficiently studied or remains unexplored. The results obtained reveal the existence of new structural complexities and oil-and gas-bearing areas has been identified, and the possibility of discovering new deposits has been suggested. In the prepared article, the integrated analysis of seismic and gravimetric data was carried out for the Alimardanly uplift in the Kura–Aghstafa interfluve, combining gravimetric results with data from drilled wells. Additionally, along the profile crossing the western part of the Qamarli structure within the Ganja OGR, the study examined the geological structure and hydrocarbon potential of a high-amplitude new structural uplift, provisionally named the Western Qamarli. In the future, detailed integrated geophysical surveys-including seismic, gravimetric, and magnetometric methodsover the newly identified structural complexities and characteristic gravity minima (indicative of hydrocarbon potential) are expected to enable the discovery of additional oil-and gas-bearing fields and deposits in the Kura Depression. At the same time, leveraging the capabilities of gravimetric exploration will help reduce the risk of drilling non-productive (dry) wells. Keywords: anomaly; characteristic gravity minimum; gravity force; gradient; Gravimetric exploration; high porosity; hydrocarbon potential; local maximum; regional profile; seismic exploration.
This study develops an analytical framework for evaluating contact pressure and wear in the plunger–cylinder pair of sucker rod pumps operating under thermoelastic deformation. The motivation arises from the sensitivity of sealing performance to clearance growth, where leakage increases approximately with the cube of the gap, making wear control crucial for long-term pump efficiency. Several existing plunger concepts are reviewed, with emphasis on the adverse role of mechanical impurities (mainly sand) that degrade sealing and intensify hydroabrasive wear. To mitigate this effect, a modified plunger design is proposed in which the end heads contain variable-diameter annular projections. These elements promote rapid fragmentation of abrasive particles in the entrance zones of the pair, reducing the probability of damaging contact and facilitating the passage of fine particles through the clearance. The contact problem is formulated by incorporating the thermoelastic radial displacements of both the plunger and the barrel into the primary compatibility condition. The unknown contact pressure is expanded into trigonometric series and determined through algebraization, with reduced linear systems solved numerically. Using the obtained pressure field, the temperature distribution in the contact region and the radial (linear) wear function ℎ(θ, t) are calculated for different plunger velocities and surface roughness conditions. The results demonstrate pronounced non-uniformity at low contact pressures and a trend toward more uniform wear as contact intensifies. The proposed structural solution and the developed calculations provide practical guidance for improving the durability and operational efficiency of sucker rod pumps. Keywords: sucker rod pump; thermoelastic deformation; plunger-cylinder pair; contact pressure; hydroabrasive wear.
In this research work, the preparation of an environmentally friendly, internationally compliant bio-component diesel fuel with minimal impact on engine performance and the study of its physicochemical properties were carried out. Fuel oil was hydrocracked at a temperature of 430 °C and a pressure of 4.0 MPa in the presence of a zeolite catalyst, yielding 60.0 wt.% diesel fraction. Grape seed oil was extracted by the cold-pressing method and transesterified with methanol at 65 °C for 120 minutes in the presence of Aydag zeolite as a heterogeneous catalyst, resulting in the synthesis of 92.9 wt.% fatty acid methyl esters (biodiesel). Infrared spectroscopic analysis confirmed the presence of carbonyl (C=O) and ester (C–O) functional groups in the biodiesel. The obtained biodiesel was blended with diesel fuel at volume ratios of 20, 40 and 60 % to prepare B20, B40 and B60 compositions. Key physicochemical properties of the fuels, including density, kinematic and dynamic viscosity, flash point, cetane number, and lubricity, were determined and compared with the requirements of PN-EN 590:2022 and PN-EN 14214+A2:2019-05 standards. It was found that the addition of biodiesel to the diesel fraction leads to a linear increase in density, viscosity, flash point, and cetane number. The cetane number of biodiesel (54.9) was higher than that of conventional diesel fuel, and an 8.93% increase in the cetane number was observed in the B60 composition. The addition of biodiesel to diesel fuel at 20-60 % (by volume) ensures technical compatibility and environmental advantages, making it a viable alternative for the energy- efficient utilization of agro-industrial waste. Keywords: biodiesel; diesel; transesterification; triglyceride; grape seed.
The utilization of wood waste for the production of solid biofuels is an important route toward sustainable energy and waste valorization. In this work, a modified phenol–formaldehyde resin (MPFR), synthesized by polycondensation of phenol and formaldehyde with an alkyl-aromatic fraction of catalytic cracking gas oil in the presence of an ionic liquid catalyst, was investigated as an efficient binder for biomass-based fuel briquettes. Beech and pine sawdust were used as fillers, and briquettes were produced by hot pressing at pressures of 50–150 MPa and temperatures of 50 - 100 °C with binder contents of 0.5–1.0 wt.%. The influence of binder content and biomass particle size on density, compressive strength, ignition behavior, combustion duration, calorific value, and ash content was systematically studied. The obtained briquettes exhibited densities of 1.4–2.0 g/cm³, compressive strength of 2.2–3.5 MPa, calorific values of 9300–11000 kcal/kg, and combustion times of 16.3–26 min. Increasing the MPFR content and optimizing sawdust particle size significantly improved mechanical integrity and combustion performance compared with binder-free briquettes. Moisture uptake tests over three months showed less than 1% mass increase, indicating good storage stability. The results demonstrate that modified phenolic resin is an effective binder for producing high-performance biomass fuel briquettes from wood waste and offers a promising route for waste-to-energy applications. Keywords: fuel briquettes; wood residues; modified phenol-formaldehyde resin; aromatic hydrocarbons; binder properties; combustion performance.
In this research, symmetric and asymmetric aliphatic esters based on 1,1,1-trimethylolpropane (TMP) were synthesized with high yields using caproic and pelargonic acids. The synthesized compounds - TMP tricaproate (N1), TMP tripelargonate (N2), and the asymmetric dicaproate-pelargonate ester (N3) - were rigorously characterized using FT-IR and NMR (1H and 13C) spectroscopy. A comprehensive study was conducted to evaluate their physicochemical properties, viscosity-temperature characteristics, and biological activities. Experimental results demonstrated that increasing the carbon chain length leads to higher kinematic viscosity and a decrease in density; specifically, sample N2 exhibited the highest viscosity, while the asymmetric N3 ester showed a superior viscosity index of 168. These balanced tribological properties suggest that these esters are highly suitable as base stocks for high-performance, low-viscosity aviation lubricants. Furthermore, the bactericidal efficiency of the esters was evaluated against sulfate-reducing bacteria (SRB). At concentrations ranging from 25 to 100 mg/L, the compounds achieved a corrosion protection effect of 96.9-100 %, significantly outperforming standard industrial reagents. Theoretical investigations were performed using Density Functional Theory (DFT) at the B3LYP/6-31G(d,p) level to calculate HOMO (Highest Occupied Molecular Orbital) - LUMO (Lowest Unoccupied Molecular Orbital) orbitals and various quantumchemical descriptors (ionization potential, electrophilicity index, chemical hardness, etc.). The substantial energy gaps (7.390-7.575 eV) confirm the high thermal and oxidative stability of these molecules. These theoretical findings strongly correlate with experimental data, providing a robust scientific framework for utilizing these TMP esters as next-generation lubricant components and effective multifunctional bactericidal inhibitors. Keywords: trimethylolpropane; esters; lubricants; bactericidal activity; DFT calculations; quantum-chemical descriptors.
This paper presents the results of an offshore field trial conducted to evaluate a newly developed demulsifier under actual operating conditions. The primary objective was to identify a more suitable chemical formulation and assess its performance against existing operational specifications, while determining its impact on three-phase (oil–gas–water) separation efficiency under varying production conditions. The trial was conducted using a structured methodology designed to ensure a reliable performance comparison without interrupting production operations. The results confirmed that separation efficiency is strongly influenced by chemical formulation. Improved separation stability had a positive impact on overall process performance, including effective residence time, liquid slugging response, and thermobaric behavior. These findings demonstrate the importance of integrated chemical and process optimization rather than reliance solely on increased chemical dosage. The enhanced stability observed under transient inlet conditions and prevailing temperature ranges is largely attributed to the diesel-based carrier solvent, which improved oil-phase compatibility and ensured consistent transport of active components to the oil–water interface. Appropriate process optimization further supported compliance with oil export and produced water quality specifications. The field trial demonstrated stable three-phase separation performance with sustained compliance with operational specifications. Optimization of the demulsification program reduced chemical consumption, improved cost efficiency, and minimized logistics-related operational risks, providing a practical framework for offshore chemical evaluation and implementation. Keywords: oil and gas production; temperature influence; demulsifiers; oil and gas separation; oil–water emulsions.
This study presents the identification and classification of eight distinct petrophysical rock types in the GCA-1 well of the Chirag field using a comprehensive petrophysical integration workflow. The Petrophysical Integration Process Model (PIPM) was applied through two independent yet complementary approaches: (1) the Winland method, supported by capillary pressure data for pore throat radius characterization, and (2) a statistical clustering methodology, including elements from Heubeck and other prior works. Both approaches yielded consistent rock type classifications and leveraged permeability as the primary distinguishing parameter, given its variation across five orders of magnitude and its dominant control on fluid flow behavior. Pittman’s R20 methodology, which defines the pore throat radius at the 20th percentile mercury saturation, demonstrated the strongest correlation between pore throat size and permeability, making it the most effective tool for rock typing in this dataset. A reasonably strong correlation between porosity and permeability was also observed, providing additional confidence in the classification results. The identified rock types show a general correspondence with depositional lithofacies as defined by Reynolds and Nummedal; however, rock types often transcend individual lithofacies boundaries. This emphasizes the need for integrated petrophysical approaches that go beyond sedimentological classification alone. The integration of multiple datasets and methodologies provides a robust foundation for reservoir characterization and flow unit delineation within a geologically complex and tectonically active setting. The workflow and findings from this study deliver valuable insights for field development planning, reservoir modeling, and future petrophysical evaluations in similar depositional systems. Keywords: Vychegda Trough; Domanic Formation; hydrocarbon potential; basin modeling; source rock; generation potential.
This study presents the first comprehensive, basin-wide assessment of offshore wind energy potential in the Caspian Sea based on a unified and reproducible analytical framework. We process 85 years (1940-2024) of hourly ERA5 reanalysis at 0.25 degrees resolution for 653 grid points, assigning each to the EEZ of Azerbaijan, Iran, Kazakhstan, Russia, or Turkmenistan. A two-stage 90th-percentile filter selects the windiest decile per EEZ; two-parameter Weibull distributions provide hub-height (100 m) wind-power density (WPD) statistics. High-potential zones cover approximate to 36,10 km(2)-10 % of the sea yet about 70-85 % of its usable wind. Median 100 m wind speeds peak in Turkmenistan (7.52 m s(-1)), however, the highest wind power density is found in Azerbaijan (613.48 W m(-2)), followed by Russia (560.62 W m(-2)), Kazakhstan (555.90 W m(-2)), and Turkmenistan (477.62 W m(-2)), while dropping significantly in Iran (168.50 W m(-2)). Shallow depths, existing oil-and-gas logistics and proximity to load centers make >= 1 GW pilot projects viable in the northern shelf before 2030. A 15 GW build-out by 2040 could displace approximate to 40 TWh of gas-fired generation and avoid approximate to 25 Mt CO2 annually. The reproducible Python pipeline forms an updatable evidence base that can be refined with LiDAR campaigns and mesoscale down-scaling to underpin bankable offshore-wind development.
