Gas Transmission Research Articles

Enhancing Gas Transmission Rate of PBS/PBAT Composite Films: A Study on Microperforated Film Solutions for Mango Storage.

This study focused on improving the mechanical properties of the poly(butylene succinate) (PBS) film by incorporation of poly(butyrate adipate terephthalate) (PBAT). At 20 wt % PBAT, elongation in the transverse direction improved by 373% while maintaining high tensile strength (27 MPa) and Young's modulus (262 MPa). The PBS80/PBAT20 composite film exhibited optimized mechanical properties. The absorbance coefficient of microperforated film at 980/cm for the 80PBS/20PBAT mix, corresponding to the 10.2 μm CO2 laser wavelength, was 65/cm, indicating high film capability to absorb energy from the CO2 laser. The introduction of microholes enhanced the gas permeability of the PBS/PBAT film. As fluences increased from 187 to 370 J/cm2, there was a notable increase in microhole area in 80PBS/20PBAT film from 19,375 to 46,421 μm2. Concurrently, the gas transmission rate for a singular hole increased from 45 to 210 cm3/d for the oxygen transmission rate (OTR) and from 115 to 220 cm3/d for the CO2 transmission rate (CO2TR). For mango packed in microperforated 80PBS/20PBAT films, the O2 levels inside the package gradually dropped and remained at 14.2% in PBS80/PBAT20-MP1 (OTR ∼ 68,900 cm3/m2·d) and 16.7% in PBS80/PBAT20-MP2 (OTR ∼ 131,900 cm3/m2·d), while CO2 content increased to 6% for PBS80/PBAT20-MP1 and 4% for PBS80/PBAT20-MP2 throughout 33 days. On day 2 of storage in the nonperforated package, O2 content dropped to 2% while CO2 content rose to 22%. Mango packed in the 80PBS/20PBAT film package exhibited an unsatisfactory freshness quality due to the detection of a fermentative odor on day 5 of the storage period. Total soluble solids, color, and weight loss of mango remained stable during storage in all microperforated films. Results demonstrated that the mango shelf life was significantly extended by 35 days using 80PBS/20PBAT-MP1. Laser perforation offered a practical method for improving gas transmission rates (OTR and CO2TR) of 80PBS/20PBAT film for mango packaging.

Effect of B. subtilis in simulated acid red soil on the corrosion behavior of X80 pipeline steel

The eastern section of China's West-east gas transmission project is laid in acidic red soil. NRB are widespread in soils and play an important role in metal corrosion. In this article, the corrosion failure behavior and mechanism of X80 pipeline steel under the action of NRB in simulated acidic soil were studied. It was found that the biofilm of B. subtilis had significant inhibitory on the overall corrosion of X80 steel. Electrochemical results prove that the corrosion rate of the sterile group after 14 days of immersion was about 4.5 times that of the bacterial group. However, the biofilm promotes the formation of local corrosion pits. Confocal laser scanning microscopy images indicate that that the corrosion pit depth of the bacterial group (46.1 μm) was three times that of the bacterial-free group (15.7 μm) after 14 days. The pH of the acidic environment was slightly improved by B. subtilis. XPS results proved that B. subtilis complicates the corrosion products of X80 steel through its nitrate reduction ability and metabolism.

Transformation of Diffusion and Local Structure of CH4 , CO2 , SO2 and H2 O Mixtures in Graphene Under Wide Temperature and Pressure Range: A Molecular Dynamics Simulation Study.

As a material with high specific surface area and excellent chemical stability, graphene exhibited remarkable adsorption and separation performance as well as a wide range of potential applications. The graphene layer played a significant role in influencing gas transmission. In this study, we employed molecular dynamics simulation to investigate the diffusion characteristics and local structures of a mixed system consisting of CH4 , CO2 , SO2 and H2 O. Additionally, we further examined the transformation of the behavior of these mixtures within graphene layers. The order of diffusion coefficients of the four molecules without graphene was H2 O>SO2 >CO2 ≫CH4 . However, in the double-layer graphene, the order changed to CH4 >CO2 ≫H2 O>SO2 . Higher temperatures and lower pressures were found to facilitate gas diffusion. Temperature and pressure had great effects on the local structures of CH4 , CO2 and SO2 , while their impact on H2 O was limited due to the extensive network of hydrogen bonds formed by H2 O molecules. The statistical results of average coordination number revealed that CH4 tended to aggregate with itself, whereas CO2 and SO2 exhibited a tendency to aggregate with H2 O. The graphene structure enhanced the separation and transportation of CH4 from mixed systems.

Analysis of sensitivity to hydrate blockage risk in natural gas gathering pipeline

During the operational process of natural gas gathering and transmission pipelines, the formation of hydrates is highly probable, leading to uncontrolled movement and aggregation of hydrates. The continuous migration and accumulation of hydrates further contribute to the obstruction of natural gas pipelines, resulting in production reduction, shutdowns, and pressure build-ups. Consequently, a cascade of risks is prone to occur. To address this issue, this study focuses on the operational process of natural gas gathering and transmission pipelines, where a comprehensive framework is established. This framework includes theoretical models for pipeline temperature distribution, pipeline pressure distribution, multiphase flow within the pipeline, hydrate blockage, and numerical solution methods. By analyzing the influence of inlet temperature, inlet pressure, and terminal pressure on hydrate formation within the pipeline, the sensitivity patterns of hydrate blockage risks are derived. The research indicates that reducing inlet pressure and terminal pressure could lead to a decreased maximum hydrate formation rate, potentially mitigating pipeline blockage during natural gas transportation. Furthermore, an increase in inlet temperature and terminal pressure, and a decrease in inlet pressure, results in a displacement of the most probable location for hydrate blockage towards the terminal station. However, it is crucial to note that operating under low-pressure conditions significantly elevates energy consumption within the gathering system, contradicting the operational goal of energy efficiency and reduction of energy consumption. Consequently, for high-pressure gathering pipelines, measures such as raising the inlet temperature or employing inhibitors, electrical heat tracing, and thermal insulation should be adopted to prevent hydrate formation during natural gas transportation. Moreover, considering abnormal conditions such as gas well production and pipeline network shutdowns, which could potentially trigger hydrate formation, the installation of methanol injection connectors remains necessary to ensure production safety.

Evaluation of the application effect of magnetic leakage detection technology in gas field gathering and transmission pipeline

Evaluation of the application effect of magnetic leakage detection technology in gas field gathering and transmission pipeline

The European natural gas system through the lens of data platforms

European Union legislation obliges natural gas transmission system operators to publish key transport indicators on a transparency platform operated by the European Network of Gas Transmission System Operators for Gas (ENTSOG). Gas Infrastructure Europe (GIE) maintains similar transparency initiatives, providing data on the use of liquefied natural gas (LNG) terminals as well as underground gas storage facilities. These platforms have become a useful source of information for researchers, practitioners, and policy makers that is available to the general public at no cost. We demonstrate that these data platforms essentially represent an archive of the European natural gas system and how the security of supply situation of Europe can be monitored in almost real time by analyzing the evolution of flow patterns on a daily basis as well as longer time horizons. In particular, we show how the system has reacted to infrastructure expansions, disruptions, and an evolving geopolitical context.

Simultaneous multi-objective framework of natural gas pipeline network operations

The optimization of gas transportation networks is essential as natural gas demand increases. Conflicting objectives, such as maximizing delivery flow rate, minimizing power consumption, and maximizing line pack, pose challenges in this context. To address these complexities, a novel multi-objective optimization method based on the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) is proposed. The method generates a diverse set of Pareto optimal solutions, empowering decision-makers to select the most suitable solution for gas transportation networks. Three case studies validate the approach's effectiveness, showcasing its advantages in yielding more economical networks and enhancing the cost-effectiveness of natural gas transmission networks. The proposed method's versatility allows application to various gas transportation network scenarios. Decision-makers benefit from a range of Pareto optimal solutions, providing valuable insights. Moreover, the seamless integration of the proposed method into existing gas transportation network optimization frameworks further enhances performance. In conclusion, the study presents a robust multi-objective optimization method based on TOPSIS for gas transportation network optimization. It offers cost-effective solutions and improves the efficiency of natural gas transmission networks. The provision of diverse Pareto optimal solutions enables well-informed decision-making, contributing to sustainable energy solutions in the face of increasing natural gas demand.

Improving failure modeling for gas transmission pipelines: A survival analysis and machine learning integrated approach

Improving failure modeling for gas transmission pipelines: A survival analysis and machine learning integrated approach

Methane gas spectral imaging method based on dual wedge scanning mirrors

With the increase in the number of oil and gas pipelines laid in China, more attention needs to be paid to pipeline maintenance work. At present, the main methods of detecting natural gas leaks in oil and gas transmission stations include manual inspections, opposing natural gas detection equipment, and cloud desktop natural gas detection equipment. Hand held natural gas detection equipment is used for manual inspection, which requires regular manual inspection. However, the response speed is poor and gas leaks cannot be detected in a timely manner. The opposed laser gas detection method can only detect the presence of gas on the beam path. If a larger area of leakage detection is desired, more equipment needs to be installed, resulting in a greatly increase in hardware costs. The existing cloud desktop laser gas detection method controls the deflection of the laser beam through the cloud platform to achieve leak detection at various points in the area to be tested. However, the rotation speed of the cloud platform is slow, and a complete detection cycle takes dozens of minutes, and only the presence of gas can be detected. For accurate leak location, manual on-site survey is also required to further determine the leak location. In order to meet the needs of the real-time monitoring and rapid positioning of oil and gas pipeline leaks, in this work, a fast and accurately controlled dual wedge scanning mirror system is designed, which combines tunable semiconductor laser absorption spectroscopy technology to convert the gas measurement laser beam from point measurement to surface measurement, thereby obtaining the two-dimensional distribution of gas, which is conducive to subsequent analysis and positioning of gas leakage sources. By using the inverse solution iterative optimization algorithm, the angle of the wedge mirror is controlled to obtain an efficient and uniform beam scanning trajectory. The deflection direction and detection position of the laser beam are fused with the corresponding methane concentration information, and a methane concentration data containing position information is constructed. In order to quantitatively verify the measurement accuracy and spatial resolution in the experiment, a standard air bag is used to simulate the methane leakage distribution. The results show that the minimum detection limit of the system can be lower than 5×10<sup>–4</sup> m, and the spatial resolution can be less than 6 cm. At the same time, this method can adjust the scanning step node based on the measurement distance of the oil from gas station, thereby achieving adjustable imaging resolution. This imaging method provides a new idea for accurately positioning and detecting the methane leakage location and amount.

Prevalence of the M1UK sublineage among emm1 Streptococcus pyogenes invasive strains isolated in the Czech Republic from December 2022 to May 2023.

Since December 2022, an increase in invasive disease caused by Streptococcus pyogenes has been observed in the Czech Republic, with a shift in the clinical presentation and age of patients. Unlike in previous years, invasive disease is more common in children and adolescents under 18 years of age and in previously healthy middle-aged adults. An increase has been noticed in the number of S. pyogenes isolates from primarily sterile sites such as haemoculture, cerebrospinal fluid, pleural effusion fluid, joint fluid, and postmortem specimens. Routine emm gene typing revealed emm1 to be the predominant emm type of S. pyogenes. Between January 2023 and July 2023, 46% of all S. pyogenes isolates from invasive cases were assigned to the emm1 type. The globallyspread M1UK sublineage is characterized by differences in the expression of seven genes, including the streptococcal pyrogenic toxin A (speA) gene, compared to historical emm1 iGAS strains. The aim of this study is to determine whether the more toxigenic M1UK sublineage is associated with the increase in invasive disease in the Czech Republic. Whole genome sequencing of 41 S. pyogenes isolates from patients with invasive disease recovered in the Czech Republic in 2018 and 2019 and from December 2022 to May 2023 was performed using the MiSeq instrument (Illumina). Bioinformatics analysis was performed using freely available online tools the Bacterial and Viral Bioinformatics Resource Center. Based on whole genome sequencing data of 41 emm1 isolates of S. pyogenes from patients with invasive infectious disease recovered in 2018 and 2019 and from December 2022 to May 2023, the M1UK sublineage was found to be predominant from December 2022 to May 2023. The reason for the spread of the M1UK sublineage in the Czech Republic late in 2022 and in the first half of 2023 is not entirely clear, but it may be related to reduced immunity due to limited GAS transmission during lockdowns, especially in children. Another factor that may have contributed to the high incidence of invasive infectious diseases is the seasonal circulation of respiratory viruses.

Joint Peak Shaving Mechanism of Pipeline Gas Storage: Case Study of West-East Gas Pipeline

Demand imbalance owing to gas supply is considered in the context of a surge in natural gas demand. Currently, a single method of storing gas at the end of a pipeline is commonly used to alleviate the peak shaving pressure. This method is economical, convenient, and able to respond quickly to fluctuations in user gas demand. However, because of its limited gas storage capacity, gas storage for peak shaving is still considered when the demand for peak shaving is high. With the increasing demand for natural gas inclined towards residential life, it is difficult to achieve a relative balance between the supply and demand of natural gas solely by relying on traditional pipeline-end storage and peak shaving. Based on this, a “pipeline gas storage integration” peak-shaving model is constructed. Furthermore, the model is combined with real-time analysis of the required peak-shaving amount of the pipeline to achieve synergistic effects of multiple peak-shaving methods. The established model is used to study the collaborative peak-shaving mechanism between pipelines and gas storage facilities under different supply and demand conditions. In addition, a quantitative relationship between the optimal economic benefits and different peak-shaving methods is constructed using the model. A peak-shaving mechanism of gas transmission considering different uniformity coefficients is also studied. Considering the case of the Jiangsu section of the West-East Gas Pipeline for simulation analysis, we reasonably plan the capacity and layout of gas storage facilities, optimize the peak shaving capacity of pipelines and gas storage facilities, and provide specific measures and guidance for actual engineering. Furthermore, we improve the efficiency and flexibility of the natural gas supply chain and achieve maximum economic benefits.

Unveiling the potential of amorphous nanocatalysts in membrane-based hydrogen production.

Hydrogen, as a clean and renewable energy source, is a promising candidate to replace fossil fuels and alleviate the environmental crisis. Compared with the traditional H-type cells with a finite-gap, the design of membrane electrodes can reduce the gas transmission resistance, enhance the current density, and improve the efficiency of hydrogen production. However, the harsh environment in the electrolyser makes the membrane electrode based water electrolysis technology still limited by the lack of catalyst activity and stability under the working conditions. Due to the abundant active sites and structural flexibility, amorphous nanocatalysts are alternatives. In this paper, we review the recent research progress of amorphous nanomaterials as electrocatalysts for hydrogen production by electrolysis at membrane electrodes, illustrate and discuss their structural advantages in membrane electrode catalytic systems, as well as explore the significance of the amorphous structure for the development of membrane electrode systems. Finally, the article also looks at future opportunities and adaptations of amorphous catalysts for hydrogen production at membrane electrodes. The authors hope that this review will deepen the understanding of the potential of amorphous nanomaterials for application in electrochemical hydrogen production, facilitating future nanomaterials research and new sustainable pathways for hydrogen production.

Правовое регулирование создание систем оповещения о чрезвычайных ситуациях на объектах транспортировки газа

In 2014, significant changes were made to the civil defense legislation which require Gazprom Group companies operating gas trunk lines, gas distributing plants, and gas compressor stations to create and maintain local emergency notification systems (LNS) in a state of immediate readiness. The objective of this study is to analyze the current legislation and the peculiarities of practical application of the LNS-related rules. The subject of the study is the social relations that arise in the course of inspections by the Ministry of Emergency Situations of Russia and the issuance of improvement notices to gas transmission organizations. The author reviews some controversial issues related to the persistent negative judicial practice in commercial courts and general jurisdiction courts for subsidiaries of Gazprom PJSC. The civil defense legislation of the CIS countries (the Republic of Belarus and Kazakhstan) is systematically reviewed. This article proposes amendments to the current legislation that would specify certain features establishing LNSs at class I and II HPFs.

The hydrogen perspective for Türkiye, which is on the Asia-Europe energy transition route. Can Türkiye become hydrogen hub?

This study examines the potential for hydrogen to undertake a leading role in the transition to sustainable energy in Türkiye. Türkiye, with its well-established energy infrastructure and increasing focus on renewable energy, has the potential to undertake a significant part in the worldwide hydrogen market. The research uses a multi-level perspective to analyse the interactions between different region connected with Türkiye, and the processes and strategies within the national energy system. The findings suggest that hydrogen production and transport in Türkiye has the potential to significantly contribute to the decarbonization of the industry and flexibility services in Asia, Europe and Africa. However, the ongoing advancement in the field of hydrogen in Türkiye is at a critical juncture where coordinated efforts are necessary to fully realize its potential. Türkiye recently announced the Hydrogen Technologies Strategy and Roadmap. Under the new Hydrogen Technologies Strategy and Roadmap, Türkiye plans to significantly increase the production of hydrogen. Türkiye plans to significantly increase its installed electrolyser capacity to support the production of hydrogen. Specifically, the plan aims to increase the installed capacity to 2 GW by 2030, 5 GW by 2035, and 70 GW by 2050. Turkey's strategic investments and policy adjustments could propel its green hydrogen production to 3.4 million tons yearly by 2050. With an anticipated domestic demand for hydrogen at 1.9 million tons annually, Turkey could potentially export between 1.5 and 1.9 million tons yearly by 2050. Türkiye boasts an extensive network of transmission and distribution pipelines for natural gas, totalling 10,000 km, including those with large diameters. The existing pipelines could transport hydrogen in its pure form or blended with natural gas. The natural gas pipeline capacity in Turkey stands at 32 billion cubic meters. This infrastructure enables the transportation of an estimated 575 million tons of hydrogen yearly to neighboring countries by employing a mix of 20 % hydrogen and natural gas. With an extensive network of natural gas transmission and distribution pipelines, Turkey positions itself as an integral part of the interconnected hydrogen energy infrastructure, linking the nation with Europe and neighboring regions. The results of this study present new approaches into the dynamics of the energy system and contribute to ongoing discussions about transition routes and consider the current status of hydrogen in Türkiye, the country's renewable energy potential, the policy and regulatory framework, and the infrastructure and market conditions necessary in order to foster the growth of a hydrogen hub.

Methodology for choosing a hydrogen source based on a point system

The article examines the usage of hydrogen in gas transmission pipes as one of the measures to achieve the criteria of sustainable development and reduction of carbon emissions. Regarding choosing an appropriate kind, hydrogen sources have been analyzed. Due to the multifactorial nature of the task, such as raw material, price, efficiency, popularity, and the availability of many studies, a point system was developed to evaluate the alternatives with significant criteria. On its basis, it was established that the cheapest and gentlest natural method is the electrolysis of water. For this purpose, electrolysis methods have been evaluated, and efficiency depends on the energy source. Given the dependence of the price of energy on the country's energy mix, a point system is proposed based on the parameters: hydrogen's levelized cost LCOH and levelized cost of electricity (LCOE). The newest criterion is the citation rating which gives popularity and an opportunity for new research.

Heavy hydrocarbon recovery with integration of turboexpander and JT valve from highly CO2-containing natural gas for gas transmission pipeline

Demand of natural gas is predicted to increase since many valuable products can be produced. Water and heavy hydrocarbon content are the key for gas pipeline facility. To meet requirement of natural gas transportation, dehydration unit (DHU) and hydrocarbon dew point control unit (DPCU) are necessary to avoid water and hydrocarbon condensation during transmission. The conventional dehydration technology, TEG contactor, can lower water content from 1,304 mg/m3 to 80.35 mg/m3 where the maximum limit of water content in natural gas is 97 mg/m3 to prevent hydrate formation. DPCU is installed to remove heavy hydrocarbon, especially C5+. Integration of JT valve and turboexpander was employed to obtain the low gas dew point. The hot gas stream that entered the JT valve was observed. The lower hot bypass gas was applied, the lower hydrocarbon dew point and the more condensate flowrate was achieved. The highest power generation can be gained at low hot gas flow ratio which also influenced the exit pressure and temperature of compressor. In pipeline simulation, the pressure and temperature drop occurred at the high hot gas rate. To examine the arrival condition, dew point curves were generated and showed that the limitation of hot gas flow ratio has to be below 0.6 to prevent heavy hydrocarbon condensation in pipeline.

Retracted: Simulation Analysis of External Damage and Repair of the Gas Transmission Pipeline

Retracted: Simulation Analysis of External Damage and Repair of the Gas Transmission Pipeline

Analisis Permintaan Penyaluran Gas PT PGN Dengan Metode Time Series

In the case of gas transmission, the calculation of the gas delivered and the gas currently in the pipe is of course required to be a safe amount in the sense of neither less nor more. A condition where the amount of gas is less than the minimum value of the pipe capacity can cause damage to the pipe because the pressure is below the normal point. Meanwhile, conditions where the gas in the pipe exceeds the maximum capacity value is also very dangerous because it can cause accidents such as pipe leaks and explosions. Therefore, this research was carried out to determine the value of forecasting gas demand by PT PGN to be able to find out the range of gas volumes that must be stored and then distributed by Pertamina Gas to meet PT PGN's demand. Forecasting is a technique of predicting the influence of prevailing conditions and situations on future developments. The method generally used in forecasting is the quantitative method using the time series method.

Influence of hydrogen blended gas transmission under transient flow on L485ME steel grade fracture toughness

Influence of hydrogen blended gas transmission under transient flow on L485ME steel grade fracture toughness

Estimating the line packing time for pipelines transporting carbon dioxide

During the operation of pressurised pipelines transporting compressible fluids, line packing is employed as an effective method that uses the pipeline itself as a buffer storage, compensating for fluctuations in the fluid supply or demand. While in large-capacity natural gas transmission systems, reaching maximum operating pressures during line packing is usually not of practical concern, in small capacity pipelines transporting low-compressibility fluids, such as liquid or dense-phase CO2, line packing can occur quickly, and therefore, estimating the line packing times becomes important to ensure avoiding exceeding the pipeline maximum allowable operating pressure. In this study, a correlation for estimating the line packing time is derived from the transient mass balance in the pipeline. The proposed correlation accounts for the pipeline overall dimensions, operating pressure and temperature, and the fluid properties, namely density and the expansion coefficient. The correlation is also adopted for the calculation of pipeline unpacking times caused by unbalanced discharge from a pipeline. A verification study on line packing in a dense-phase CO2 pipeline shows that within the ranges tested, the proposed correlation estimates conservatively the line packing times with ca. 15 % deviation from the results of simulations obtained using a rigorous transient pipeline flow model. The proposed correlation is also verified against predictions obtained using a parabolic flow model and is recommended for estimating line packing times for both dense-phase and gas-phase CO2 at pressures and temperatures in the ranges 2 - 12 MPa and 280 – 330 K, respectively. The limitations of the proposed line packing time correlation are discussed.