Gas Field Research Articles

Production, Characterization and Application of Biosurfactant for Cleaning Cotton Fabric and Removing Oil from Contaminated Sand

Biosurfactants are a group of environmentally friendly amphiphilic molecules that are applicable in numerous industries as essential biotechnology products, such as food production, cleaning products, pharmacology, cosmetics, pesticides, textiles and oil and gas fields. In this sense, and knowing the potential of these biomolecules, the aim of this work was to produce a biosurfactant, characterize it regarding its chemical and surfactant properties and investigate its potential in the removal of contaminants and in the cleaning of cotton fabrics. The biosurfactant was initially obtained from the cultivation of the microorganism Candida glabrata UCP 1002 in medium containing distilled water with 2.5% residual frying oil, 2.5% molasses and 2.5% corn steep liquor agitated at 200 rpm for 144 h. The biosurfactant reduced the surface tension of water from 72 to 29 mN/m. The toxicity potential of the biosurfactant was evaluated using Tenebrio molitor larvae and demonstrated non-toxicity. The biosurfactant was applied as a degreaser of engine oil on cotton fabric, and showed 83% (2× CMC), 74% (1× CMC) and 78% (1/2× CMC) oil removal. Therefore, the biosurfactant produced in this work has promising surfactant and emulsifying properties with potential for application in various industrial segments.

A Comprehensive Review of Advanced Treatment Technologies for the Enhanced Reuse of Produced Water

Produced water (PW) is considered to be the largest source of industrial wastewater associated with oil and gas extraction operations for industrial production. It is a mixture of organic and inorganic compounds that has high complexity in terms of various characteristics. Globally, the volume of PW is increasing along with the expansion of gas and oil fields, leading to major impacts on the environment. Existing treatment technologies involve partially treating the PW through removing the suspended solids, heavy metals, without removing organic components and re-injecting the water underground using water disposal injection wells. The treatment process consists of a primary treatment unit to remove the particles, followed a secondary biological or chemical processing treatment, while the final treatment stage involves the use of a tertiary treatment unit to improve the water quality and remove the remainder of the undesired components. Moreover, while PW is considered one of the available options to be utilized as a water source, no alternate advanced treatment options on a commercial scale are available at present due to the limitations of existing PW treatment technologies, associated with their maintainability, sustainability, cost, and level of quality improvement. As such, research focused on finding an optimal treatment approach to improve the overall process continues to be conducted, with the aim of reusing the water instead of injecting it underground. This literature review discusses the latest advanced technologies for PW treatment aimed at reusing the full stream capacity of PW and eliminating the need for wastewater disposal via injection. It is concluded that researchers should focus on hybrid treatment technologies in order to remove the pollutants from PW, effectively allowing for its reuse.

Imaging Enhancement of Gas Reservoir via Full-Waveform Inversion Imaging: Case Study, Gas Field

Abstract Seismic data are essential for analyzing and characterizing reservoir distributions in oil and gas exploration. While many advances have been made to obtain accurate seismic data, conventional methods still have limitations. The main limitations include the inability to use the full wavefield and the time-consuming sequential process of preprocessing, velocity model building, and migration. These challenges have highlighted the need for more efficient and accurate data processing. Full-waveform inversion (FWI) and FWI imaging have been developed to address these drawbacks. FWI uses the full wavefield, including diving and multi-scattered waves, to predict subsurface properties. It uses an optimization that iteratively updates the model to minimize the residual between the observed and the modeled data. Moreover, FWI imaging derives seismic images in a short time by taking the directional derivative of the FWI results. Compared with conventional methods, FWI imaging, since it is based on FWI, improves the signal-to-noise ratio and mitigates migration artifacts. In this study, a case study was conducted using 3D streamer data from a deepwater gas field to demonstrate the effectiveness of FWI imaging. As the gas field contains shallow gas, conventional methods have limitations in restoring subgas zones. To overcome this, FWI imaging was introduced, and to verify its effectiveness, reverse time migration (RTM) was used for comparison. After updating the velocity model with FWI up to 25 Hz, FWI imaging and RTM were applied using the same velocity model. Compared with RTM, FWI imaging exhibited significant improvements in resolution and structural detail at various depths. Additionally, it improved lateral resolution and structural continuity and effectively suppressed noise. Furthermore, FWI imaging significantly reduces processing time by eliminating the need for preprocessing and migration. These findings suggest that FWI imaging is a promising alternative to conventional methods by providing high-quality subsurface information while reducing the processing time.

Propagation and distribution of shear and tensile hydraulic fractures affected by frictional coal beddings.

As a typical sedimentary rock, coal seams are usually rich in bedding planes, which significantly affect the propagation process of hydraulic fracture (HF) network and reservoir permeability. In this study, the profile characteristics and the bedding roughness of the coal seam at depth of 2800m from Daniudi Gas Field in China is investigated. The failure mechanism of shear-expansion effect under low pressure and dynamic shear under high pressure of coal beddings induced by the dissolution-corrosion effect of fracturing liquid is analyzed. The development process of HF network under different bedding angles, joint roughness coefficients (JRCs), stress differences, and confining pressures is numerically simulated by cohesive element method. Results show that the JRC of coal beddings has significant effects on the morphology of HF networks. When the JRC exceeds 15, a HF network structure with tensile main fractures and shear secondary cracks is developed. The shear fractures account for a considerable proportion (33-66%) multi-layer layered coal seams and should be taken seriously during reservoir reconstruction. As confining pressure increases, the total length of tensile HFs sharply decreases, while the change in the total length of shear HFs is not significant. When the confining pressure increases from 5 to 15MPa, the length ratio of shear HFs to tensile hydraulic fractures increases from 0.36 to about 1, confirming that increasing confining pressure can promote the transformation of HF failure types from tension to shear. The ratio of secondary crack to main crack length is between 6.31 and 9.78, indicating the secondary fractures occupy an absolute proportion in the hydraulic fracture network. This study is of significance for understanding the hydraulic fracture network development in coal reservoirs.

GEOLOGICAL FEATURES OF SYRIAN OIL FIELDS

Over the past 60 years, exploration in Syria has focused on the major late Paleozoic and Mesozoic sedimentary basins. Source and reservoir rocks were deposited during major regional extensional periods in the late Paleozoic and Mesozoic. Oil and gas fields are concentrated mainly in the eastern and northeastern regions of the country, including the Palmyra, Deir-ez-Zor and Homs areas. The main oil fields are concentrated in the north-eastern and eastern regions of the country, in the oil and gas regions of Rmeilan, Tishreen, Jibsin, Tim and Ward. Most of the gas fields are located in the Palmyra region. The reserves of recoverable oil in Syria are estimated at 350 mln m3, and the reserves of recoverable gas – at 250 bln m3. According to some estimates, the recoverable resources of shale oil on land are about 7 bln m3. On the territory of Syria, with a total area of 2190 km², there are huge gas reserves – 600–700 bln m3 and oil reserves – 50 mln m3. New objects can be explored in Paleozoic and Mesozoic petroleum systems. Stratigraphic traps may include Paleozoic siliciclastic successions, isolated Cretaceous carbonate buildups or Jurassic-Cretaceous carbonate platforms and karsts, and marine basin-floor siliciclastic fans.

The Gas Generation Process and Modeling of the Source Rock from the Yacheng Formation in the Yanan Depression, South China Sea

The research on deepwater oil and gas exploration areas is relatively limited, and sample collection is difficult. A drilled coal sample from Yanan Depression was used to investigate the hydrocarbon generation process, and the potential, by a gold tube thermal simulation experiment. The results show that the total gas yield was much higher than the oil yield. According to an analysis of the gas pyrolysis data, as represented by ln(C1/C2) and ln(C2/C3), the gas generation process consisted of two forms, namely, primary gas with ~1.33% Ro and secondary gas that occurred at levels greater than 1.33% Ro. The primary gas from kerogen was generated at ~1.33% Ro, which coincided with the %Ro value of the maximum oil yield. The activation energy distribution of the C1–C5 generation processes ranged from 54 to 72 kcal/mol, with a frequency factor of 6.686 × 1014 s−1 for the coal sample. We constructed the history of gas generation on the basis of the process and kinetic parameters, combined with data on the sedimentary burial and thermal history. The extrapolation of the gas history revealed that the gas has been generated from 5 Ma to the present, with a maximum yield of 178.5 mg/gTOC. This history suggests that the coal has good primary gas generation potential and provides favorable gas source conditions for the formation of gas fields. This study provides a favorable basis for expanding the effective source rock areas.

Application of Digital Technology for Oil and Gas Fields

The paper investigates the problem of isothermal filtration using an approximate method for solving the theory of partial differential equations. The mathematical model under consideration is nonlinear and does not lend itself to analytical methods of solution. The results obtained indicate the need for wide application in the development of oil and gas fields in the Republic of Kazakhstan. In particular, the results of the study make it possible to solve the problems of adapting mathematical models and evaluating changes in technological indicators, which are necessary attributes in the digital technology ""Information System for the Analysis of oil and Gas Field Development"" (ISAR). Many problems and mathematical problems of filtration theory arose while working on specific oil and gas fields in the western region of the Republic of Kazakhstan. The above approximate solution methods have found applications not only in filtration theory, but also in other problems (geophysics, ecology, etc.)"

High-resolution isochronous stratigraphic framework through well-seismic integration in tight sandstone: a case study of Luodai gas field, Sichuan, China

Tight gas sandstone represents a significant unconventional resource extensively discovered across numerous sedimentary basins around the world. Tight sandstone reservoirs are characterized by low porosity, low permeability, variable source material, rapid spatial and temporal changes, poor reservoir properties, and strong heterogeneity. Traditional geophysical methods struggle to meet the demands of exploration and development of these types of reservoirs. This study applies a high-precision comparative approach using well-seismic integration to establish a relative isochronous stratigraphic framework. Based on this framework, extracting seismic properties can effectively predict tight sandstone reservoirs. This paper, focusing on the Penglaizhen Formation in the Luodai Gas Field of the Western Sichuan Jurassic system. This entire process accomplished in three steps: starting with regional marker layers as the initial framework; followed by the establishment of a relative isochronous framework through precise well-seismic integration; and finally stratigraphic slicing techniques to delineate isochronous stratigraphic framework with shorter time intervals. Thereby enhancing the reliability of subsurface stratigraphic information and data accuracy. The study posits that current technological means cannot create a truly isochronous stratigraphic framework; thus, “isochronous” is considered a relative concept in this context. The framework aims to ensure temporal consistency by minimizing discrepancies through mutual constraints between well and seismic data, serving to exploration and development requirements. Furthermore, analyses such as sensitive attribute extraction, impedance inversion, and assessment of hydrocarbon potential in tight sandstone reservoirs demonstrate strong correlation with drilling results. This validation underscores the framework’s efficacy in interpreting industrial gas production flows, thereby providing robust support for future oil and gas exploration.

Research on the Blocking Mechanism of Stagnant Water and the Prediction of Scaling Trend in Fractured Reservoirs in Keshen Gas Field

In this paper, well Keshen 221 was taken as the research object. The stagnant water–rock static experiment showed that, after 8 weeks of the residual water–rock static reaction, the pore size of the inner profile of the rock slice increased from 5 μm to 90 μm, and calcium carbonate crystals were deposited in the hole. Combined with the microscopic visualization model, it is observed that the reservoir blockage mostly occurs at the pore throat diameter, and the small fracture (30 μm) is blocked first, then the large fracture (50 μm). So, it is inferred that the blockage of the reservoir flow channel is caused by the migration of the crystals precipitated by the interaction between the stagnant water and the reservoir rock. On this basis, the TOUGHREACT reservoir model was further constructed to simulate the scaling of the stagnant water in the reservoir matrix and used to compare the scaling of the fractures with 7% and 30% porosity and the retained water at 0.658 m and 768 m. The pre-results of reservoir scaling show that the scaling is more serious when the fractures occur in the far well zone than when the fractures occur in the well entry zone. At the same location, the deposition of large fractures is six times that of small fractures, and the scaling is more severe in large fractures.

Prediction of Thin Shoal Reservoirs Under Reef Controlled by Isochronous Stratigraphic Framework

Despite the great success in the global exploration and development of reef reservoirs, research on bioclastic shoals under reefs is still in its infancy. Bioclastic shoal reservoirs are very thin, with multiple vertical levels and fast lateral changes, which makes accurate prediction of the reservoir’s location much tougher. To further implement the reservoir distribution, under the guidance of sequence stratigraphy, the prediction of thin shoals under the control of an isochronous stratigraphic framework was established. Using the combination of spectrum shaping and F-X domain noise suppression techniques and utilizing the signal-to-noise ratio spectrum set as the reference, logging curve as supervision, and well seismic calibration and isochronal amplitude slicing as quality control, the seismic frequency band was extended, and the seismic data resolution and signal-to-noise ratio were improved. After frequency extension, the global optimal seismic automatic interpretation technique was used to construct an isochronal stratigraphic framework model. Through waveform facies-controlled inversion and waveform facies-controlled simulation techniques, the elastic properties of the shoal reservoir were obtained, from which the planar distribution of the reservoir was accurately predicted. The above methods were applied to the prediction of the bioclastic shoal reservoir in the lower submember of the Changxing formation in the Yuanba gas field (China). The plane distribution of bioclastic shoal in the first and second levels was identified, which provides a guideline for the prediction of thin shoal reservoirs.

Vibration analysis of push-the-bit rotary steerable bottom hole assembly

With the development of oil and gas fields to the deep-sea, the rotary steerable system is widely used. Downhole vibration is an important factor affecting the performance of rotary steerable system. Currently, the lack of research on vibration during operation of rotary steerable system has affected the development of deep-sea oil and gas field development technology. In this paper, the dynamic model of the push-pull rotary steerable system is established based on the similarity principle. The model includes Bit-rock interaction model, Drillstring-borehole contact model and guiding force model of rotary steerable system, the trajectory and vibration of drill bit under different guiding forces are simulated. Then, the actual drilling experiment of the full-scale Push-The-Bit Rotary Steerable System (PTB-RSS) in the horizontal section is carried out. The acceleration and speed signals of the push-pull rotary steerable system in the process of applying guiding force are collected and verified with the calculation results of the dynamic model. It is found that the vibration frequency and amplitude of the Bottom Hole Assembly (BHA) gradually increase with the increase of the guiding force of the PTB-RSS during the drilling stage, which induce high-frequency torsional vibration to a certain extent. In addition, the dynamic simulation shows that when the guiding force of the rotary steerable system is increased to a certain extent, the vibration of the BHA gradually stabilizes, but the vibration amplitude does not decrease.

Synthesis and Evaluation of New Type Plant Extraction Corrosion Inhibitor

The use of corrosion inhibitors in the development of oil and gas fields is an important means of effectively preventing metal corrosion, at present, the green growth of the oil and gas industry requires low-toxicity, low-residue, easy-to-post-treatment and other environmentally friendly corrosion inhibitors, however, most industrially used corrosion inhibitors such as mercury salts quaternary ammonium salts, and imidazolines are toxic to some degree. In this paper, a plant extract corrosion inhibitor was synthesized, firstly, the purple sweet potato extract was extracted by ethanol, and then the purple sweet potato extract and alkyl halide such as methane were used to produce the purple sweet potato corrosion inhibitor through condensation extraction and other processes, and the corrosion inhibitory performance of the inhibitor was evaluated by the loss-in-weight method, scanning electron microscopy, polarization curves, and impedance spectroscopy. The results show that there is a certain inhibition effect on N80 steel in the simulated stratum water environment, and the retardation rate can reach 91.38% in the gas phase, and the corrosion product morphology and chemical elements on the surface of N80 steel specimens were characterized by SEM, EDS, and it can be observed that a relatively dense protective film was formed after adding purple sweet potato corrosion inhibitor, and the corrosion inhibition rate can be known according to the weightlessness curve, Tafel curve and impedance curve. The corrosion inhibition rate increases with the increase of corrosion inhibitor concentration.

A multi-objective decision-making framework for the choice between mutually exclusive alternatives under uncertainty: Assessing the competitiveness of offshore wind for a gas field electrification on the NCS

A multi-objective decision-making framework for the choice between mutually exclusive alternatives under uncertainty: Assessing the competitiveness of offshore wind for a gas field electrification on the NCS

Facies associations dispersion via rule-based simulation with genetic algorithm and kriging: A methodology conditioned by seismic facies

Rule-based simulation of facies is a valuable tool in oil and gas field exploration. The manuscript presents a hybrid methodology for simulating facies associations, using paleobathymetry as the main data and seismic facies as the secondary. A dispersion model of facies, which is based on paleobathymetry and wave energy is proposed, and the parameters of this dispersion are optimized via genetic algorithm, using seismic facies. The relationship between seismic facies e facies associations is quantified in order to construct a fitness function used in genetic algorithm to select good parameters for the dispersion model. In order to refine the model generated by the genetic algorithm, we use indicator kriging to adjust the simulation to the available well data. The methodology was applied to data from the Sapinhoa field-Brazil, focusing on three ages, 113 Ma, 114 Ma, and 115 Ma. The results obtained demonstrate that the simulated facies association maps largely respect the geometries observed in the seismic facies, and at the same time, honor the data from wells along the simulated area. The results demonstrate that the simulated facies association maps largely respect the geometries observed in the seismic facies while honoring well data across the simulated area. This approach addresses the inherent uncertainties and biases in traditional facies modeling, providing a more reliable and automated method for calibrating facies intervals.

Geoelectric heterogeneities of the Pre-Dobrudga Trough a zone of hydrocarbon manifestations

For the first time, a geological and geoelectrical interpretation of the three-dimensional model of the Earth’s crust and upper mantle was carried out for the Pre-Dobrudga Trough and adjacent areas. It was based on observations of the Earth’s low-frequency electromagnetic field conducted in 2009―2012 by the National Academy of Sciences of Ukraine. The material confidently indicates that hydrocarbon occurrences are confined to the detected anomalies of high electrical conductivity. These are characterized by subvertical channels (from the surface to 10 km deep) galvanically connected with sediments or sub-vertical contact zones of different resistivity observed not only in the Earth’s crust (10―40 km) but also at crust-mantle depths (40―60 km) and in the upper mantle (110―160 km).The channels may determine the flow of ultra-deep fluids. The geoelectric criteria included maximum thickness of the sedimentary stratum, subvertical rise of electrical conductivity anomalies from the crust-mantle depths or column to the entire thickness of the Earth’s crust, subvertical boundaries of heterogeneities (contacts of different resistivity) in the consolidated Earth’s crust and upper mantle,presence of a highly conductive asthenospheric layer. We identified a significant number of local areas that can be considered promising for hydrocarbon occurrence. The majority of them spatially coincided with the already well-known oil and gas fields ― Skhidnosaratske and Zhovtoyarske, with the explored oil and gas prospective areas (Izmailska, Kyslytska, Prymorska, Shyrokivska), and with those that correspond to the areas of special permits for industrial exploration. However, the newly discovered areas that meet most of the geoelectric criteria, but for which no no information on oil and gas content is publicly available, clearly require additional geological and geophysical studies. It has been shown that zones of high electrical conductivity caused by the presence of deep fluids should be considered as deep centers of hydrocarbon generation and ways of their migration to the upper horizons of the Earth’s crust.

Analysis of the reservoir properties of rocks of the Lower Kura depression (Azerbaijan)

The article analyzes the features characterizing the Lower Kura depression (LKD). A number of hydrocarbon deposits have been discovered in this oil and gas region. The Kalmas underground gas storage facility, which has the largest volume in Azerbaijan, is also located in this area. In the LKD, all PS formations can be traced throughout the entire well section. The reservoir properties of the rocks were considered to study the features of the area. In order to study the reservoir properties in the well section, the field applies data obtained by using a complex of well logging (WL) methods (laterolog, spontaneous potential logging, induction logging, gamma logging, neutron logging, acoustic logging) and analyses of rock samples. The graphs were constructed to evaluate the relationship between petrophysical parameters (porosity, permeability, etc.) determined in the rocks involved in the well sections of the object of research. In the article, maps of porosity distribution, permeability and permeability of sandy siltstone rocks and fractions greater than 0.1 of the Productive Series of the South-Eastern Gobustan and Baku Archipelago, which are part of the Low Kura Depression, are plotted and analysed. Plots showing the porosity distribution of the Low Kura Depression by depth were also constructed and some results were obtained. Based on reservoir properties, the region is divided into 6 groups, and in each group intermediate values of the porosity and permeability coefficient are determined. In general, the porosity coefficient ranges within 5-25%, permeability – 1-250 mD. The reservoir properties of rocks vary over area from worse to better. The capacitance-filtration properties of rocks were studied. The rock samples analysed identified rocks with good and low reservoir characteristics. To study the variation in the determining factors, maps of the distribution of reservoir properties indicators (fractions greater than 0.1 mm; porosity and permeability in sand-siltstone-containing rocks) were compiled by area and their causes were determined by comparison with other oil and gas fields. It was found that with distance from the mouth of the Kura River (towards the right and left banks), the reservoir properties of the rocks deteriorate. This is due to an increase in the amount of clay in rocks. It is also clarified that the change in porosity coefficient does not depend on depth. The content of sand-siltstone composition in the rocks along the section is 20-50%.

Diagnosis of GHG Emissions in an Offshore Oil and Gas Production Facility

This work presents a diagnosis of greenhouse gas (GHG) emissions for floating production storage and offloading (FPSO) platforms for oil and gas production offshore, using calculation methodologies from the American Petroleum Institute (API) and U.S. Environmental Protection Agency (EPA). To carry out this analysis, design data of an FPSO platform is used for the GHG emissions estimation, considering operations under steady conditions and oil and gas processing system simulations in the Aspen HYSYS® software. The main direct emission sources of GHG are identified, including the main combustion processes (gas turbines for electric generation and gas turbine-driven CO2 compressors), flaring and venting, as well as fugitive emissions. The study assesses a high CO2 content in molar composition of the associated gas, an important factor that is considered in estimating fugitive emissions during the processes of primary separation and main gas compression. The resulting information indicates that, on average, 95% of total emissions are produced by combustion sources. In the latest production stages of the oil and gas field, it consumes 2 times more energy and emits 2.3 times CO2 in terms of produced hydrocarbons. This diagnosis provides a baseline and starting point for the implementation of energy efficiency measures and/or carbon capture and storage (CCS) technologies on the FPSO in order to reduce CO2 and CH4 emissions, as well as identify the major sources of emissions in the production process.

Hydrate management strategies for CO2 injection into depleted gas reservoirs

Sequestering CO2 in depleted gas reservoirs using carbon capture, utilization, and storage technologies has emerged as a viable strategy for mitigating global carbon emissions. However, CO2 hydrate formation during injection processes is challenging and poses a risk to the operational integrity and efficiency of sequestration projects. This study investigated CO2 hydrate formation dynamics within silica gel environments that closely mimicked the median pore size of natural sandstone reservoirs, particularly targeting depleted gas fields in the East Sea of Korea. Integrating kinetic insights into experimental hydrate formation assessments and molecular dynamics simulations provided a comprehensive understanding of the CO2 hydrate formation mechanisms, as well as the formation dynamics and stability of the CO2 hydrates. For example, the hydrate formation kinetics were significantly reduced in the small pores, suggesting the feasibility of implementing more economical hydrate inhibitor injection strategies during CO2 injection. Moreover, this study evaluated the inhibitory effects of NaCl and methanol on CO2 hydrate stability by accurately measuring the three-phase (H-Lw-V) equilibria and employing silica gels (6 nm pore size). The presence of methanol and amorphous silica significantly impacted hydrate formation, with methanol potentially influencing the local structure around the hydrate phase and silica hindering hydrate growth through dynamic interactions with CO2 molecules. In addition, we elucidated the complex interplay between CO2, water, and methanol (hydrate inhibitor) within the constrained environments of porous media, offering strategic insights for the development of effective CO2 injection and sequestration strategies. Integrating molecular-level observations with real-world geological modeling presents a novel methodology for enhancing the safety, efficiency, and environmental sustainability of carbon capture and storage operations. The findings of this study provide critical insights into hydrate phase behavior, highlighting the importance of precise equilibrium determination under simulated reservoir conditions to effectively anticipate and mitigate hydrate formation challenges.

Underground Hydrogen Storage: Comparison of High-pressure Hydrogen, Liquid Hydrogen, and Ammonia

One of the alternatives for effective storage of irregularly produced renewable energy is hydrogen energy. In order to realize a hydrogen-based society, not only environmentally friendly production of hydrogen but also effective storage is very important. Underground hydrogen storage technology is a technology that has evolved from the technology for storing natural gas underground, and includes waste gas fields, salt domes, aquifers, and rock cavities. When stored underground, hydrogen is converted into high-pressure gaseous hydrogen, liquefied hydrogen, and ammonia. Liquefied hydrogen requires extremely low storage temperatures, and ammonia is a toxic substance that requires separate handling, and energy loss occurs during the conversion process. To compensate for this, research on liquefied hydrogen, such as multilayer insulation technology, is being conducted. Ammonia has successfully extracted high-purity hydrogen by developing a membrane reactor. Ammonia toxicity can be prevented by strengthening leak detection and blocking facilities. Among these, ammonia was found to be the most suitable for underground storage in terms of economic feasibility, environment, and commercialization.

Device for preventing the formation of liquid plugs in a gas collection system or in a non-straight gas well

Relevance. Almost all gas fields, both in Russia and in the world, are developed under water-pressure conditions, which means that sooner or later the field operator is faced with the problem of well watering and liquid accumulation at their bottom. The control methods proposed at this stage of development of science and technology and the useful models and inventions applied for this, although they show their effectiveness in removing droplet liquid from the production wellbore, do not contribute to the further advancement of the removed fluid through the system for collecting and preparing products. Because of this fact, a number of problems arise, for example, the formation of local resistance in the form of ice or hydrate plugs, the cause of which is the fluid removed from the wellbore. Aim. Development of a universal device that can be used both in the production collection and preparation system and inside production wells, capable of injecting produced water into the gas flow in order to prevent the formation of “stagnant zones” of liquid. Objects. Flooded gas wells, the gas pressure in which is not enough to remove droplet liquid from the wellbore or transport this liquid to the place of product preparation. Methods. Assessment and analysis of existing devices to prevent the formation of liquid plugs in a gas collection system, identifying their main shortcomings, as well as mathematical modeling of the proposed model, in which these shortcomings are eliminated. Results and conclusions. The paper introduces a brief description of the problem under study and studies and discusses the main methods of preventing the formation of liquid plugs, used in gas fields both in Russia and in other countries. The authors have proposed the design of a universal device, which is devoid of the main identified disadvantages of analogue devices, and carried out its simplified mathematical calculation.