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During the transportation of hydrogen-blended natural gas (HBNG) through the natural gas pipeline network, the accuracy of the physical property model for real gas greatly influences the reliability of aerodynamic performance of compressor systems and the hydrothermal characteristics of pipeline networks. In this study, the adaptability of various equations of state (EOS) in predicting physical property parameters including compressibility factor, enthalpy difference, entropy difference, specific heat capacity, specific heat ratio and viscosity of natural gas (NG) and HBNG is evaluated based on the experimental data and NIST REFPROP firstly. The properties calculated using NIST REFPROP are compared with those from the EOSs, such as cubic EOSs (Redlich–Kwong EOS (RK), Soave–Redlich–Kwong EOS (SRK), Peng–Robinson EOS (PR)) and Soave-Benedict-Webb-Rubin (BWRS) EOS. After confirming the reliability of NIST REFPROP as the calculation benchmark, the accuracy of the four EOSs in calculating the physical properties of HBNG is assessed within the temperature range of 250∼350 K, pressure range of 1∼25 MPa, and hydrogen doping ratio of 0%–30%. Besides, the mixing rules of different equations of state (EOSs) are compared based on the NIST REFPROP calculation results. The results indicate that, except for specific heat capacity calculation, the mixing rule has little influence on the prediction accuracy of cubic EOS models, and the maximum calculation error between different mixing rules of the same EOS model does not exceed 0.5%. Under specific conditions, the traditional mixing rule exhibits better prediction accuracy and can be prioritized due to its simplicity. Furthermore, the pressure has a significant impact on the accuracy of EOS models, with the prediction accuracy decreasing as the pressure increased. The influence of temperature on the prediction accuracy is less significant than that of pressure. Generally, lower temperatures exhibit lower prediction accuracy, while higher temperatures show higher prediction accuracy. Among the cubic EOS models, the RK equation performs better than the SRK and PR EOS models. While the cubic EOSs show minimal differences in predicting specific heat ratio with an average relative error below 1%, the RK EOS shows significant advantages in predicting other physical parameters. The simple structure of RK EOS meets the calculation requirements for HBNG engineering. The comprehensive comparisons reveal that, the BWRS EOS has higher accuracy in predicting various physical properties parameters, with the maximum average relative error not exceeding 5% for each physical property parameter, and its stability is also better compared to the cubic EOSs. The further analysis shows that, the calculation of viscosity is influenced not only by the EOS but also by the viscosity model. When calculating viscosity using the LU-Model, the PR EOS provides the most accurate results. In contrast, when utilizing the LGE-Model or LBC-Model, the BWRS EOS demonstrates superior accuracy compared to other EOSs. • Mixing rules slightly effect state equations' accuracy across different x-H2, besides heat capacity calculations. • Unlike other parameters, the viscosity calculation depends on both the viscosity model and the equations. • Apart from viscosity calculations, Redlich-Kwong equation performs the best among the cubic state equations. • The Benedict-Webb-Rubin-Starling equation is more accurate than the cubic state equations overall. • The impact of pressure on equations' accuracy for hydrogen-blended natural gas is more obvious than that of temperature. [ABSTRACT FROM AUTHOR]

Hydrogen production is a vital development trend to improve the economics and penetration rate of offshore wind farms (OWFs), and distributed hydrogen production (DHP) is a preferred solution for deep and far sea OWFs without expensive submarine cables and offshore substations. The export pathway of OWF-DHP consists of collection pipelines, transmission pipelines, and offshore compressor stations. In this paper, mathematical programming is introduced to explore the export pathway planning problem of OWF-DHP. Firstly, the area of OWF is discretized into multiple grids with the center of the grids being the candidate locations of the offshore compressor station. Then, a binary integer quadratic programming problem is established to optimize both the offshore compressor station location and pipeline construction with different topologies. Further, the mathematical model is solved by the branch and cut algorithm integrated with the proposed dimension reduction methods. Finally, the effectiveness of the proposed export pathway planning approach is verified by the actual data of Baltic Eagle OWF in Germany, which would support the construction of the OWF-DHP project. [Display omitted] • Studying export pathway planning (EPP) for OWF-distributed hydrogen production. • Introducing mathematical programming to model EPP as a BIQP problem. • Proposing dimension reduction methods to accelerate BIQP problem solving. • Verifying the effectiveness of the EPP approach with the Baltic Eagle OWF case. • Conducting sensitivity analysis on transportation carrier and pipeline topology. [ABSTRACT FROM AUTHOR]

Mineral slurry preparation and pipeline transport require careful particle size distribution and additive selection to ensure cost-effective and reliable transportation. The research described here was aimed to better understand the flow behavior of a limestone sample by combining coarse and fine particles and a low-cost natural additive, Saponin, derived from Sapindus laurifolia. Four distinct bi-modal suspension samples were formed using various mixtures of limestone samples with sizes varying from 0–53 and 75–106 µm. The rheological characteristics of the suspension were investigated at shear rates of 50 to 500 s−1 for solid concentrations 40–70% by weight. The additive's critical micelle concentration was found to be 1.8 weight percent. The Hershel-Bulkley model fits the experimental data the best. The appropriate proportion of coarse particles was discovered to be 30% based on critical factors such as apparent viscosity and pressure drop. The addition of the surfactant reduced the surface tension, increased the wettability, and decreased the particle-particle interaction to stabilize the limestone-water suspension. [ABSTRACT FROM AUTHOR]

We investigate the challenges and options for repurposing existing natural gas pipelines for hydrogen transportation. Challenges of re-purposing are mainly related to safety and due to the risk of hydrogen embrittlement of pipeline steels and the smaller molecular size of the gas. From an economic perspective, the lower volumetric energy density of hydrogen compared to natural gas is a challenge. We investigate three pipeline repurposing options in depth: a) no modification to the pipeline but enhanced maintenance, b) use of gaseous inhibitors, and c) the pipe-in-pipe approach. The levelized costs of transportation of these options are compared for the case of the German Norddeutsche Erdgasleitung (NEL) pipeline. We find a similar cost range for all three options. This indicates that other criteria such as the sunk costs, public acceptance, and consumer requirements are likely to shape the decision making for gas pipeline repurposing. • Three options for repurposing a natural gas pipeline to use with hydrogen are considered. • The levelized costs of hydrogen transport of each option are calculated. • The calculations are for the case study of the NEL pipeline in Germany. • Levelized costs of hydrogen transport are similar between the three options. [ABSTRACT FROM AUTHOR]

Hydrogen is a promising solution for the decarbonisation of several hard-to-abate end uses, which are mainly in the industrial and transport sectors. The development of an extensive hydrogen delivery infrastructure is essential to effectively activate and deploy a hydrogen economy, connecting production, storage, and demand. This work adopts a mixed-integer linear programming model to study the cost-optimal design of a future hydrogen infrastructure in presence of cross-sectoral hydrogen uses, taking into account spatial and temporal variations, multiple production technologies, and optimised multi-mode transport and storage. The model is applied to a case study in the region of Sicily in Italy, aiming to assess the infrastructural needs to supply the regional demand from transport and industrial sectors and to transfer hydrogen imported from North Africa towards Europe, thus accounting for the region's role as transit point. The analysis integrates multiple production technologies (electrolysis supplied by wind and solar energy, steam reforming with carbon capture) and transport options (compressed hydrogen trucks, liquid hydrogen trucks, pipelines). Results show that the average cost of hydrogen delivered to demand points decreases from 3.75 €/kg H2 to 3.49 €/kg H2 when shifting from mobility-only to cross-sectoral end uses, indicating that the integrated supply chain exploits more efficiently the infrastructural investments. Although pipeline transport emerges as the dominant modality, delivery via compressed hydrogen trucks and liquid hydrogen trucks remains relevant even in scenarios characterised by large hydrogen flows as resulting from cross-sectoral demand, demonstrating that the system competitiveness is maximised through multi-mode integration. [Display omitted] • A hydrogen supply chain model is extended to study delivery to multi-sector demand. • Industrial uses impose flat profiles with large quantities, while mobility demand is more variable. • The cost-optimal hydrogen infrastructure relies on combined transport modes. • Cross-sectoral deployment of hydrogen has positive impact on the cost of infrastructure. [ABSTRACT FROM AUTHOR]

In the field of CO2 capture and sequestration, ensuring the safety of pipeline infrastructure is paramount to successful climate change mitigation efforts. This study investigates the dynamics of CO2 dispersion from pipeline systems, assessing not only the transport process but also the physical properties and associated hazards. Advanced simulation techniques are used to model how different states of CO2 (gas, liquid, and supercritical) and varying pipeline characteristics—such as perforation sizes, flow rates, and orientations—affect the dispersion patterns in the event of a leak. Simulations cover a range of atmospheric conditions, emphasizing the role of atmospheric stability and wind speed in shaping dispersion and defining potential impact zones. An analysis of historical pipeline accidents is included to inform risk management strategies. The results show that the orientation of the pipeline has a significant effect on dispersion, with downward leaks causing the largest impact zones, particularly under supercritical conditions. The results highlight the need for adaptive safety strategies that take into account real-time CO2 transport conditions and localized environmental data. By integrating these factors, the study recommends refining safety protocols and emergency response strategies to improve pipeline resilience and public safety against potential leaks. Key findings include the quantification of the relationship between leak parameters and dispersion areas, providing a valuable framework for future safety improvements. [ABSTRACT FROM AUTHOR]

Deep-sea mining, as a critical direction for the future development of mineral resources, places significant importance on the mechanical characteristics of its transportation pipelines for the safety and efficiency of the entire mining system. This paper establishes a simulation model of the deep-sea mining system based on oceanic environmental loads and the mechanical theory of deep-sea mining transportation pipelines. Through a static analysis, the effective tension along the pipeline length, the maximum values of bending moment, and the minimum values of bending radius are determined as critical points for the dynamic analysis of pipeline mechanical characteristic monitoring. A dynamic simulation analysis of the pipeline's mechanical characteristics was conducted, and simulation sensor data were obtained as inputs for the prediction model construction. A prediction model of pipeline mechanical characteristics based on the BP neural network was constructed, with the model's prediction correlation coefficients all exceeding 0.95, enabling an accurate prediction of pipeline state parameters. [ABSTRACT FROM AUTHOR]

Hydrogen safety remains a paramount concern in pipeline transportation. Once hydrogen leaks and ignites, it quickly escalates into a jet fire incident. The substantial thermal radiation released poses significant risks of fire and explosion. Therefore, studying the thermal radiation characteristics of hydrogen jet fires and developing accurate prediction models are crucial for establishing relevant safety standards. To address the oversimplified consideration of weighted coefficients in thermal radiation prediction models, this study investigated the thermal radiation characteristics of hydrogen jet fire by carrying out experiments and numerical simulations. The results reveal the significant impacts of the leakage diameter and pressure on thermal radiation. Increases in both the leakage diameter and pressure lead to a rapid escalation in the thermal radiation release, highlighting their critical importance in establishing safety standards for hydrogen pipeline transportation. Additionally, this study optimized the weight coefficients in the multi-point source prediction model based on temperature distribution along the flame axis. The optimized model was validated through comparison with experimental data. After optimization, the prediction error of the multi-point source radiation model was reduced from 19.5% to 13.9%. This model provides significant support for accurately evaluating the risk of hydrogen jet fire. [ABSTRACT FROM AUTHOR]

In the context of dual-carbon strategy, the insulation performance of the gathering and transportation pipeline affects the safety gathering and energy saving management in the oilfield production process. PCM has the characteristics of phase change energy storage and heat release, combining it with the gathering and transmission pipeline not only improves the insulation performance of collecting and transporting pipes, but also extends the safe shut time during the shutdown. Proposed a thermal model of a PCM-based composite energy storage pipeline combining the character of phase transformation between PCM and crude oil has been established. The heat preservation performance of the combined energy storage pipeline was evaluated by numerical simulation.This paper analyses the heat transfer performance of complex energy storage pipes, and considers the influence of natural convection and variable temperature zone on insulation performance.On this basis, the structure design of cascade phase transition was proposed, the optimized cascading composite pipe was presented, and the performance of different insulation structures was compared. [ABSTRACT FROM AUTHOR]

Gas–liquid two-phase bubbly flow has significant applications across multiple fields, including reactor design and separation processes in chemical engineering, oil well extraction and pipeline transportation in the oil and gas industry, cooling systems in the nuclear industry, and wastewater treatment in environmental engineering. Bubble monitoring is crucial in these applications as it can enhance mass and heat transfer efficiency, improve flow stability, and ensure the safe operation of systems. This study developed an advanced algorithm aimed at precisely detecting and segmenting small bubbles at the gas–liquid interface using semantic segmentation techniques. This technology leverages deep learning models to analyze images, automatically identifying bubbles at the gas–liquid interface and accurately delineating their boundaries. The technique provides precise contours for each bubble, offering essential foundational data for further bubble dynamics analysis. Building on this, the deep learning detection algorithm was combined with the Deep Simple Online and Realtime Tracking with a Deep Association Metric (DeepSORT) algorithm, tracking algorithm, enabling the system to rapidly and accurately identify and track the movement of the same bubble across consecutive frames. [ABSTRACT FROM AUTHOR]

Some of the foremost parameters effecting the slurry rheology, preferably the slurry concentration, particle size distribution, and modal distributions, were studied in the current findings, figuring out the variation in shear stress and apparent viscosity using a rotational rheometer. The particle size considered for the test ranges from fine particle size of −75 µm to coarse particle size of +75–300 µm, separated at varied size fractions of +75–105, +105–150, +150–210, and +210–300 µm. The −75 µm bauxite slurry at 60 wt% has shown a maximum static settled concentration (Cw-max) under gravity after 48 h free settlement. This fine particle slurry at varying concentrations of Cw = 45–65% is discerned to behave like a Non-Newtonian Bingham plastic fluid at lower concentrations, unlike the other coarse fraction bauxite slurries at Cw = 55%, which exhibit shear thickening behavior. The present work carried out adds knowledge on the rheological behavior of bimodal, trimodal, and multimodal with four and five different size fraction bauxite slurries in finding the optimum mass concentration for a particle size fraction of (coarse):(fine), obtained in the ratio (25):(75), (25:25):(50), (25:25:10):(40), and (15:15:15:15):(40), respectively of the total 60 wt%. Certain parameters, like yield stress, consistency index (k), and flow behavior index (n), were estimated upon fitting the modal distributions to the Herschel Bulkley model to choose the best particle size distribution of the bauxite sample showing improved slurry stability, rheology, and flow characteristics. [ABSTRACT FROM AUTHOR]

Pipeline transportation is the main means of transportation of oil, natural gas and other energy sources. During transportation, corrosive substances in oil and natural gas can cause damage to the pipeline structure. A non-destructive testing technology for pipeline corrosion based on electromagnetic ultrasound technology was proposed to improve the stability and safety of energy pipeline transportation systems. This technology utilized empirical mode decomposition and singular spectrum analysis to denoise electromagnetic ultrasound signals. The designed electromagnetic signal denoising algorithm completely removed mild noise pollution. When using this method to detect pipeline corrosion, the maximum calculation error of pipeline wall thickness was 0.1906 mm, and the lowest was 0.0015 mm. When detecting small area corrosion deficiency, the amplitude of the detection signal increased with the depth, up to a maximum of around 24 V, which accurately reflected small area defects. This non-destructive testing technology for pipelines can effectively detect the pipeline corrosion, which is helpful for the regular maintenance of pipeline energy transmission systems. [ABSTRACT FROM AUTHOR]

With the rapid development of the pipeline transportation and exploitation of mineral resources, there is an urgent requirement for high-performance polymer matrix composites with low friction and wear, especially under oxidative and prolonged working conditions. In this work, ultra-high-molecular-weight polyethylene (UHMWPE) matrix composites with the addition of carbon fibers (CFs), TiC, and MoS2 were prepared by the hot press sintering method. The influence of thermal oxygen aging time (90 °C, 0 h–64 h) on their mechanical and frictional performance was investigated. The results showed that TiC ceramic particles can increase wear resistance, especially by aging times up to 32 and 64 h. The wear mechanisms were analyzed based on the results of SEM images, EDS, and Raman spectra. The knowledge obtained herein will facilitate the design of long-service-life polymer matrix composites with promising low friction and wear performances. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents an assessment of the levelized cost of clean hydrogen produced in Sicily, a region in Southern Italy particularly rich in renewable energy and where nearly 50% of Italy's refineries are located, making a comparison between on-site production, that is, near the end users who will use the hydrogen, and centralized production, comparing the costs obtained by employing the two types of electrolyzers already commercially available. In the study for centralized production, the scale factor method was applied on the costs of electrolyzers, and the optimal transport modes were considered based on the distance and amount of hydrogen to be transported. The results obtained indicate higher prices for hydrogen produced locally (from about 7 €/kg to 10 €/kg) and lower prices (from 2.66 €/kg to 5.80 €/kg) for hydrogen produced in centralized plants due to economies of scale and higher conversion efficiencies. How-ever, meeting the demand for clean hydrogen at minimal cost requires hydrogen distribution pipelines to transport it from centralized production sites to users, which currently do not exist in Sicily, as well as a significant amount of renewable energy ranging from 1.4 to 1.7 TWh per year to cover only 16% of refineries' hydrogen needs. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to use the corresponding magnetic sensor and detection method to detect and image the defects of small diameter pipelines. Urban gas pipeline is an energy transportation tool for urban industrial production and social life, which is closely related to urban safety. Preventing the occurrence of urban gas pipeline transportation accidents and carrying out pipeline defect detection are of great significance for the urban economic and social stability. To perform pipeline defect detection, the magnetic flux leakage internal detection method is generally used in the detection of large-diameter long-distance oil and gas pipelines. However, in terms of the internal detection of small-diameter pipelines, due to the heavy weight, large structure of the detection device and small pipe diameter, the detection is more difficult. Design/methodology/approach: In order to solve the above matters, self-made three-dimensional magnetic sensor and three-dimensional magnetic flux leakage imaging direct method are proposed for studying the defect identification. Firstly, for adapting to the diameter range of small-diameter pipelines, and containing the complete information of the defect, a self-made three-dimensional magnetic sensor is made in this paper to improve the accuracy of magnetic flux leakage detection. And on the basis of it, a small diameter pipeline defect detection system is built. Secondly, as detection signal may be affected by background magnetic field interference and the jitter interference, the complete ensemble empirical mode decomposition with adaptive noise method is utilized to screen the detected signal. As a result, the useful signal is reconstructed and the interference signal is removed. Finally, the defect contour inversion imaging of detection is realized based on the direct method of three-dimensional magnetic flux leakage imaging, which includes three-dimensional magnetic flux leakage detection data and data segmentation recognition. Findings: The three-dimensional magnetic flux leakage imaging experimental results shown that, compared to the actual defects, the typical defects, irregular defects and crack groove defects can be analyzed by the magnetic flux leakage defect contour imaging method in qualitative and quantitative way respectively, which provides a new idea for the research of defect recognition. Originality/value: A three-dimensional magnetic sensor is made to adapt the diameter range of small diameter pipeline, and based on it, a small-diameter pipeline defect detection system is built to collect and display the magnetic flux leakage signal. [ABSTRACT FROM AUTHOR]

In this paper, an experiment has been conducted where additive materials have been added to heavy crude oil to improve transportation. This is done on a pipeline length of 186 km. During the experiment, materials will be added to the inner pipeline to lubricate the heavy crude oil fiber and reduce the pressure drop. The additive materials, which are Drag-Reducing Agents (DRAs) (These are polymers that reduce the friction between the crude oil and the pipeline walls) are injected into heavy crude oil at different doses (two materials); the doses are 4, 6, 8, 10, and 12. A comparison between the cases before and after this additive has been obtained in the pipeline for velocity magnitude, vorticity magnitude, pressure drop, and wall shear stress. It can be observed that doses (8, 10, and 12) obtained a wide range of flow rates with fewer pressure drops than other dose points. The pressure at the city of Al-Faw has been found, and the maximum values are 1.482, 1.413, and 1.399 MPa for doses 12, 8, and 6, respectively. The simulation was done with COMSOL 5.4 Multiphasic software. Flow ranges increase as the dose increases. Shear stress increases with mass injection rate. Transporting heavy crude oil long distances is easier with additive materials. After the additive materials are added, crude oil will be transported for a long time without pressure drops, increasing the flow rate. The two turbines pump heavy crude oil through a 48 inches wide and 186 km long pipeline. These pipelines transfer heavy crude oil from the refinery to Al-Faw City. [ABSTRACT FROM AUTHOR]

The present article investigates the effect of thermal shrinkage on the yielding behavior of waxy oil gel. The paper compares constant gap and constant normal force measurement protocols to examine the effect of measurement protocol on the rheological behavior of thermoreversible gel. The findings of this study reveal that the extent of stress overshoot and yield stress in a constant shear-rate start-up flow shows a lower magnitude in a constant gap protocol compared to a constant normal force protocol. The decrease in gel strength in the former protocol is mainly attributed to the formation of voids. These voids cause localized fractures within the crystal network. In contrast, in the constant normal force measurement protocol, gel contraction is compensated by utilizing a variable gap setting. Variable gaps compensate for the lower specific volume of the gel after crystallization, minimizing void formation and subsequent rupture of the crystal network. Hence, the gel network formed using the constant normal force protocol is more homogeneous, eliminating the uncertainties in yield stress measurement. Finally, the effect of thermal history, wax content, and aging period on the yield stress values highlights notable findings. Contrary to the conventionally accepted results, the aging period is found to impact the yield stress negatively, and a nonmonotonic relationship between the cooling rate and yield stress is noticed under the constant gap protocol. Thus, the results obtained under the constant normal force protocol are more reliable and can help in developing a fundamental understanding of the yielding behavior. [ABSTRACT FROM AUTHOR]

Purpose: With the rapid development of the pipeline transportation and exploitation of mineral resources, it is urgent requirement for the high-performance polymer matrix composites with low friction and wear to meet the needs of solid material transportation. This paper aims to prepare high-performance ultrahigh molecular weight polyethylene (UHMWPE) matrix composites and investigate the effect of service condition on frictional behavior for composite. Design/methodology/approach: In this study, UHMWPE matrix composites with different content of MoS2 were prepared and the tribological performance of the GCr15/composites friction pair in various sliding speeds (0.025–0.125 m/s) under dry friction conditions were studied by ball-on-disk tribology experiments. Findings: Results show that the frictional behavior was shown to be sensitive to MoS2 concentration and sliding velocity. As the MoS2 content is 2 Wt.%, composites presented the best overall tribological performance. Besides, the friction coefficient fluctuates around 0.21 from 0.025 to 0.125 m/s sliding speed, while the wear rate increases gradually. Scanning electron microscopy images, energy-dispersive spectroscopy and Raman Spectrum analysis present that the main wear mechanisms were abrasive and fatigue wear. Originality/value: The knowledge obtained herein will facilitate the design of UHMWPE matrix composites with promising self-lubrication performances which used in slag transport engineering field. [ABSTRACT FROM AUTHOR]

In view of the problems of frequent leakage and corrosion failure in a gathering and transportation pipeline in Jiyuan Oilfield, water quality analysis, corrosion and scaling product analysis, surface morphology and element composition analysis were carried out. The corrosion mechanism under multi-media environment of CO2, H2S, dissolved oxygen, Cl and scaling ions was studied, and the corrosion and scaling treatment methods were optimized. The results show that the main factors causing pipeline corrosion are CO2-H2S-Cl- co-existing corrosion and bacterial corrosion, which promote the development of local corrosion. By new corrosion inhibitor and coating combined anti-corrosion technology, the on-site corrosion rate is reduced to 0.001 8 mm/a, which can minimize or reduce the corrosion of gathering and transportation pipelines, and extend its service life. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Predicting the decompression behavior and controlling the fracture of CO2 pipelines are crucial research areas for the safe transport of CO2. Existing decompression wave prediction models have problems such as large errors in calculating the sound speed of the gas-liquid two-phase flow and difficulties in convergence near the critical point. The local sound speed calculation method based on isochoric thermodynamics was improved and a new decompression wave prediction model was established. The effects of gas compositions, initial phase state, initial pressure, and initial temperature on decompression wave curves and pressure drop curves were calculated and analyzed. Additionally, the decompression behavior of CO2 pipeline leaks in practical engineering scenarios was predicted. The results show that compared to post-combustion capture or pre-combustion capture, the initial decompression wave speed under gas by oxy-fuel combustion capture is reduced by approximately 26%, and the decompression plateau pressure increases by 22%. During the decompression process, the temperature and pressure operating point of medium inside the pipeline no longer move along the gas-liquid equilibrium line but directly enter the gas-liquid two-phase region. Compared to the dense phase state, the saturation pressure corresponding to the intersection of the pressure drop curve and the CO2 bubble point line is about 26% higher in the supercritical state, and the decompression plateau pressure is higher. Lower operating temperatures and higher operating pressures can effectively reduce the decompression plateau pressure. Due to the differences in operating parameters along the pipeline, the risk of pipeline fracture decreases sequentially from the starting point of the pipeline, with the front section of the pipeline being the high-risk section. This study provides a theoretical basis for CO2 pipeline design and engineering applications. [ABSTRACT FROM AUTHOR]

In deep-sea mixed transmission mining systems, the mixed transmission hard pipe plays an important role in mineral transport. To speed up the process of connecting the hard pipe, a quick disassembly and assembly system was designed. By model analysis, the key focus of the rapid disassembly and assembly system was the clamp connector. On the basis of vibration theory and finite-element simulations, the connector underwent static and vibration analysis, and the fatigue life was predicted. Finally, laboratory and sea test tests were conducted on the rapid disassembly and assembly system. The quick disassembly and assembly system can realise quick disassembly and assembly under the target working conditions and maintained smooth operation during two 24-h cycle tests. [ABSTRACT FROM AUTHOR]

The circular economy and the clean-energy transition are inextricably linked and interdependent. One of the most important areas of the energy transition is the development of hydrogen energy. This study aims to review and systematize the data available in the literature on the environmental and economic parameters of hydrogen storage and transportation technologies (both mature and at high technological readiness levels). The study concluded that salt caverns and pipeline transportation are the most promising methods of hydrogen storage and transportation today in terms of a combination of all parameters. These methods are the most competitive in terms of price, especially when transporting hydrogen over short distances. Thus, the average price of storage will be 0.35 USD/kg, and transportation at a distance of up to 100 km is 0.3 USD/kg. Hydrogen storage underground in a gaseous state and its transportation by pipelines have the least consequences for the environment: emissions and leaks are insignificant, and there is no environmental pollution. The study identifies these methods as particularly viable given their lower environmental impact and potential for seamless integration into existing energy systems, therefore supporting the transition to a more sustainable and circular economy. [ABSTRACT FROM AUTHOR]

The high viscosity of Indian heavy crude oils makes their pipeline transportation highly complicated and challenging. A huge pressure drop is observed while transporting heavy crude through pipelines. The present article addresses this complication by preparing a surfactant stabilized heavy crude oil-in-water (O/W) emulsion of a flowable viscosity to ease flow through pipelines. Different O/W emulsion samples were prepared with varying concentrations of a novel anionic surfactant, linear alkylbenzene sulfonic acid (LABSA), to achieve an optimized formulation based on rheological and stability studies. The article also discusses the effect of varying surfactant concentrations on interfacial tension, droplet size and distribution, and zeta potential of the developed emulsions. The optimized emulsion, having 60 vol% oil and 2 wt% surfactant, was further considered to simulate and analyze the flow characteristics (static pressure and velocity profiles) across the horizontal pipelines of three different inner diameters (0.1, 0.05, and 0.025 m) under three different inlet flow velocities (0.1, 0.05, and 0.001 m/s), using a computational fluid dynamics (CFD) approach. A remarkable decrease in the viscosity of heavy crude was noted after emulsification. Subsequently, the pressure drop across the pipeline was reduced significantly by order of three for the flow of O/W emulsion when compared to that of the heavy crude oil through a pipe diameter of 0.1 m at an inlet velocity of 0.1 m/s. The static pressure drop across the pipeline decreased with the increase in the pipe diameter; in contrast, it increased with the increase in the inlet velocity. [ABSTRACT FROM AUTHOR]

This study aims to develop a sustainable freight transportation network considering capacitated cross-docks for minimising the overall supply chain costs, including carbon emission cost. The problem is inspired by a major retail company based in India, which would like to expand its product portfolio in the new region. A mathematical model is developed to minimise total costs encompassing transportation cost, pipeline and retailers inventory cost, fixed cost of cross-dock and carbon emission costs. The deterministic time dependant demand, multiple products and multiple sourcing and distribution are some of the challenges faced by the retail industry. A two-level self-adaptive variable neighbourhood search algorithm is applied to solve a computationally complex problem. The results based on a two-level self-adaptive variable neighbourhood search algorithm are compared with the variable neighbourhood search algorithm to test the robustness of the developed model. Results reveal that an increase in retailers over suppliers significantly influences the number of open cross-docks. A multiple-case scenario approach captures the implications of varying capacity on the number of open cross-docks; thus, supporting the freight distribution managers in making sustainability-driven decisions. [ABSTRACT FROM AUTHOR]

Abstract As climate issues gradually attract public attention worldwide, the operation of crude oil pipelines has been attached with new emission‐reduction targets. Though previous studies concerning life cycle assessment (LCA) of oil and gas pipelines have estimated the carbon footprint to some extent, there is a lack of research on life cycle carbon emissions that take the process of crude oil pipelines transportation. the main objective of this study is to build a comprehensive LCA model of carbon footprint for crude oil pipeline systems. A gate‐to‐gate analysis is provided for the LCA model, which means that the entire pipeline's life cycle from the extraction to disposal is considered. The LCA approach used both midpoint and endpoint impact assessment methods to evaluate the environmental impacts of crude oil pipeline transportation in Iran. The study analyzed the major environmental impact categories, such as greenhouse gas emissions, energy consumption, water usage, and solid waste generation. The results showed that the crude oil pipelines transportation has significant environmental impacts in Iran. The three highest impacts on the midpoint scale are marine ecotoxicity by 61.54 kg 1,4‐DCB, terrestrial ecotoxicity by 52.26 kg 1,4‐DCB and fossil resource scarcity by 40.22 kg oil eq. The endpoint impacts of three stations were also compared. The Chamran, Abadan and Zanganeh stations have 95.44%, 94.22%, and 6% impacts on human health, respectively. Also, Abadan station has the largest amount of damage to ecosystems and resources with 96.65% and 80.02%, respectively. The findings of this study could be used by policymakers, oil companies, and other stakeholders to make informed decisions and implement strategies to reduce the environmental impact of oil transportation in Iran.

Buried pipeline, as one of the crucial facilities of airport ground engineering, has been extensively utilized for the transportation of petroleum, natural gas, industrial wastewater, and more. However, there are significant gaps in the research on the dynamic response of buried pipelines in airports under the action of dynamic traffic loads, which severely hampers the design and engineering quality of oil transmission pipelines. This study builds a three-dimensional finite element model to simulate the action of vehicles on the pipe–soil structure with actual loads. Moreover, the current research establishes a dynamic analysis model of pipe–soil interaction to analyze the material damping and load parameters. Using the structural dynamic response equation and Rayleigh damping calculation theory, this study investigates the change law of pipe dynamic stress and influencing factors and presents the recommended values of the parameters related to the pipe–soil interaction. Results are as follows. A damping ratio of 0.05 can enhance the time lag of the dynamic response of the structure and weaken the response peak. For the Rayleigh damping parameters, the viscous damping coefficient α has almost no effect on the dynamic response of the pipe–soil structure, so it can be disregarded in the calculation. With the increase of the axial weight of the traffic load above the pavement structure, the peak value of each dynamic response quantity of the pipe–soil structure and load magnitude. The suggested value of the dynamic load coefficient of the pipe–soil structure is 1.5. Lastly, the earth pressure and dynamic load coefficients are suggested to take values for different load and axle type cases. [ABSTRACT FROM AUTHOR]

Meeting Germany's climate targets urgently demands substantial investment in renewable energies such as hydrogen, as well as tackling industrial CO2 emissions with a strong CO2 transport infrastructure. This is particularly crucial for CO2-heavy industries such as steel, cement, lime production, power plants, and chemical plants, given Germany's ban on onshore storage. The CO2 transport network is essential for maintaining a circular economy by capturing, transporting, and either storing or utilizing CO2. This study fills gaps in CO2 pipeline transport research, examining pipeline diameters, costs, and pressure drop, and providing sensitivity analysis. Key findings show that the levelized cost of CO2 transport (LCO2T) ranges from 0.25 €/t to 55.82 €/t based on varying transport masses (1000 t/day to 25,000 t/day) and distances (25 km to 500 km), with compression costs pushing LCO2T to 33.21 €/t to 92.82 €/t. Analyzing eight pipeline diameters (150 mm to 500 mm) and the impact of CO2 flow temperature on pressure loss highlights the importance of selecting optimal pipeline sizes. Precise booster station placement is also crucial, as it significantly affects the total LCO2T. Exploring these areas can offer a more thorough understanding of the best strategies for developing cost-effective, efficient, and sustainable transport infrastructure. [ABSTRACT FROM AUTHOR]

The node pressure and flow rate along the shale gas flow process are analyzed according to the characteristics of the shale gas flow pipe network, and the non-leaking and leaking processes of the shale gas flow pipe network are modeled separately. The changes in pressure over time along each pipe segment in the network provide new ideas for identifying leaking pipe sections. This paper uses the logarithmic value of pressure as the basis for judging whether the flow pipe network is leaking or not, according to the process of varying flow parameters resulting in the regularity of leakage. A graph of the change in pressure of the pipe section after the leak compared to the pressure of the non-leaking section of pipe over time can be plotted, accurately identifying the specific section of pipe with the leak. The accuracy of this novel method is verified by the leakage section and statistical data of the shale gas pipeline network in situ used in this paper. [ABSTRACT FROM AUTHOR]

The use of existing natural gas pipelines for the transport of hydrogen/natural gas mixtures can achieve large-scale, long-distance and low-cost hydrogen transportation. A jet fire induced by the leakage of high-pressure pure hydrogen and hydrogen-blended natural gas pipelines may pose a severe threat to life and property. Based on the Abel–Nobel equation of state and a notional nozzle model, an equivalent pipe leakage model is established to simulate high-pressure pipeline gas leakage jet fire accidents. Large-scale high-pressure hydrogen and natural gas/hydrogen mixture jet fires are simulated, showing the jet impingement process and obtaining an accurate and effective simulation framework. This framework is validated by comparing the simulated and experimental measured results of flame height, flame appearance and thermal radiation. Several combustion models are compared, and the simulated data show that the non-premixed chemical equilibrium combustion model is superior to other combustion models. The influence of the pipe pressure and the hydrogen blending ratio on the consequences of natural gas/hydrogen mixture pipeline leakage jet fire accidents is explored. It is found that when the hydrogen blending ratio is lower than 22%, the increase in the hydrogen blending ratio has little effect on the decrease in the thermal radiation hazard distance. [ABSTRACT FROM AUTHOR]

The use of natural additives in pipeline transportation has gained significant attention in recent years due to their potential to enhance the stability and rheology of the suspension. In this study, the dispersing and stabilizing properties of the saponin extracted from the fruits of Sapindus laurifolia are examined in the pipeline transportation of limestone. The physicochemical, morphological, and flow characteristics of limestone samples less than 75 μm are determined. The rheological behaviors of the suspension have been examined by varying the shear rate, solid, and dispersion concentrations. The critical micelle concentration of the dispersant was determined to be 1.8 wt%. In the tested concentration ranges of 40–70%, the Hershel–Bulkley model best matched the data. When the surfactant was added to the suspension, the water's surface tension was lowered, increasing the wettability of the limestone particles and decreasing particle-particle contact. Increases in zeta potential measurements confirmed that the steric component primarily stabilizes limestone water suspension. Finally, the dispersant's economic impact was studied depending on slurry head loss and specific energy consumption. [ABSTRACT FROM AUTHOR]

Urban areas contribute to over 80% of carbon dioxide emissions, and considerable efforts are being undertaken to characterize spatiotemporal variations of CO2 (carbon dioxide) at a city, regional, and national level, aiming at providing pipelines for carbon mission reduction. The complex underlying surface composition of urban areas makes process-based and physiology-based models inadequate for simulating carbon flux in this context. In this study, long short-term memory (LSTM), support vector machine (SVM), random forest (RF), and artificial neural network (ANN) were employed to develop and investigate their viability in estimating carbon flux at the ecosystem level. All the data used in our study were derived from the long-term chronosequence observations collected from the flux towers within urban complex underlying surface, along with meteorological reanalysis datasets. To assess the generalization ability of these models, the following statistical metrics were utilized: coefficient of determination (R2), root mean square error (RMSE), and mean absolute error (MAE). Our analysis revealed that the RF model performed the best in simulating carbon flux over long time series, with the highest R2 values reaching up to 0.852, and exhibiting the smallest RMSE and MAE values at 0.293 μmol·m−2·s−1 and 0.157 μmol·m−2·s−1. As a result, the RF model was chosen for simulating carbon flux at spatial scale and assessing the impact of urban impervious surfaces in the simulation. The results showed that the RF model performs well in simulating carbon flux at the spatial scale. The input of impervious surface area index can improve the performance of the RF model in simulating carbon flux, with R2 values of 84.46% (with the impervious surface area index in) and 83.74% (without the impervious surface area index in). Furthermore, the carbon flux in Fengxian District, Shanghai, exhibited significant spatial heterogeneity: the CO2 flux in the western part of Fengxian District was less than in the eastern part, and the CO2 flux gradually increased from the west to the east. In addition, we creatively introduced the diurnal impervious surface area index based on the Kljun model, and clarified the influence of impervious surface on the spatiotemporal simulation of CO2 flux over the complex urban underlying surface. Based on these findings, we conclude that the RF models can be effectively applied for estimating carbon flux on the complex underlying urban surface. The results of our study reduce the uncertainty in modeling carbon cycling in terrestrial ecosystems, and make the variety of models for the carbon cycling of terrestrial ecosystems more diverse. [ABSTRACT FROM AUTHOR]

Repurposing existing natural gas pipelines for hydrogen transport requires an accurate assessment of the distribution of hydrogen (H) atoms at defects, such as dents, under frequent pressure fluctuations experienced by gas pipelines. In this work, a 3-dimensional finite element-based model was developed to determine the stress/strain and H atom concentrations at an unconstrained dent on an X52 steel pipe which experienced denting, spring-back and cyclic loading processes. As expected, stress and strain concentrations generate at the dent center. However, the cyclic loading reduces the stress level and shifts the stress concentration zone from the dent center along the circumferential direction. As the dent depth increases, the maximum H atom concentration is further shifted from the dent center to the side. There are no certain relationships among the maximum H atom concentration, von Mises stress, hydrostatic stress, and plastic strain in terms of their distributions and quantities. Pressure fluctuations decrease both the stress and H atom concentrations at the dent, providing a beneficial effect on reduced risk of the dented pipelines to hydrogen embrittlement in high-pressure hydrogen gas environments. The indenter size has little influence on the H atom distribution in the dent area. [ABSTRACT FROM AUTHOR]

Cooperation among enterprises can bring overall and individual performance improvement, and a smooth coordination method is indispensable. However, due to the lack of customized coordination methods, cooperation in the downstream oil supply chain cannot be carried out smoothly. This paper intends to propose a multi-party coordination method to promote cooperation between oil shippers and pipeline operator by optimizing oil transportation, oil substitution and pipeline pricing schemes. An integrated game-theoretic modeling and analysis approach is developed to characterize the operation behaviors of all stakeholders in the downstream oil supply chain. The proposed mixed integer nonlinear programming model constrains supply and demand capacity, transportation routes, oil substitution rules and pipeline freight levels. Logarithm transformation and price discretization are introduced for model linear approximation. Simulation experiments are carried out in the oil distribution system in South China. The results show that compared to the business-as-usual scheme, the new scheme saves transportation cost by 3.48%, increases pipeline turnover by 5.7%, and reduces energy consumption and emissions by 7.66% and 6.77%. It is proved that the proposed method improves the revenue of the whole system, achieves fair revenue distribution, and also improves the energy and environmental benefits of the oil supply chain. [ABSTRACT FROM AUTHOR]

Oil-gas two phase wax deposition is a fairly common and open-ended question in flow assurance of multiphase transportation pipelines. This paper investigated the two main aspects of oil-gas two phase wax deposition layer: apparent thickness and crystal structure characteristics. A typical highly paraffinic oil in Bohai Sea, China, was used as the experimental material to investigate the wax deposition thickness in oil-gas two phase under the influence of different oil temperatures, superficial gas/liquid phase velocities and gas-oil ratios by using multiphase flow loop experimental device. Just as in the classical theory of wax molecular diffusion, it showed that wax deposition thickness of oil-gas two phase increased with increasing oil temperature. Analysis of the impact of different superficial phase velocities found that the actual liquid flow heat transfer and shear stripping was the gas phase dominant mechanisms determining wax deposit thickness. In addition, the crystal structure of the wax deposition layer was characterized with the help of small-angle X-ray scattering (SAXS) for different circumferential positions, flow rates and gas-oil ratios. The bottom deposition layer had a complex crystal structure and high hardness, which were subject to change over flow rate variations. Furthermore, the SAXS results provided evidence that the indirect effect of the actual liquid velocity modified by the gas phase was the main mechanism. Our study of the effect of gas phase on the wax deposition of oil-gas two phase will help shed light onto the mechanism by which this important process occurs. Our findings address a very urgent need in the field of wax deposition of highly paraffinic oil to understand the flow security of oilgas two phase that occurs easily in multiphase field pipelines. [ABSTRACT FROM AUTHOR]

The oil pipeline transportation of highly waxy oils when it is cold is accompanied by the deposition of paraffins in the inner surface of the pipeline. This study of the initial properties of the oil; the composition, structure, and nature of the components of normal alkanes in oil; and their influence on the aggregative stability of the resulting system makes it possible to find the best solutions to optimize the conditions of oil transportation with the lowest energy costs. This study shows that, according to the content of solid paraffin (14.0–16.2%), the oils of the Kumkol group of fields in Kazakhstan are highly waxy. They are characterized by high yield loss temperature values (+9–+12 °C), which also correlate with the values of the rheological parameters (τ0 1.389 Pa, 3.564 Pa). The influence of the temperature and shear rate on the shear stress and effective viscosity of the initial oils was studied. At temperatures below 20 °C, depending on the shear rate, there is an increase in the effective viscosity values (0.020 Pa∙s, 0.351 Pa∙s). The influence of the nature of solid hydrocarbons on the parameters of the paraffinization process and of the intensity of the paraffinization of the metal surfaces was studied. Our study shows that the main share of n-alkanes in the Kumkol and Akshabulak oils falls on paraffins of the C15–C44 group. The greater the temperature difference between the oil and the cold steel surface (≤40 °C), the lesser the amount of asphalt–resin–paraffin deposits (ARPDs) that fall out on the surface of the rod, although the content of long-chain paraffins prevails in these ARPDs. At the same time, the consistency of the released asphalt–resin–paraffin deposits (ARPDs) becomes denser, which makes their mechanical removal more difficult. Furthermore, the results of this study of the cooling rate shows that the rapid cooling of oils leads to the formation of a large number of crystallization centers, which leads to an increase in the values of the yield loss temperature and kinematic viscosity of the oils. [ABSTRACT FROM AUTHOR]

The article is devoted to the development of a vehicle suspension with a nonlinear characteristic based on a torsion bar and an elastic hinge with a given characteristic on the example of tracked vehicles for constructing oil and gas pipelines. The characteristic of the elastic hinge is such that when the existing torsion bar suspension and the elastic hinge are connected in parallel, the desired characteristic is obtained. For this non-linear characteristic in the static displacement region, low stiffness was obtained, but the total stored energy at the maximum deflection of the balance bar of the resulting suspension is greater than that of existing torsion suspensions. The smoothness of the tracked vehicles with a low stiffness of the suspension increases significantly. The calculation of vibrations of the proposed suspension under kinematic excitation was carried out. A harmonic function is considered as the trajectory of the profile; a function corresponding to a single obstacle and a function corresponding to an ascent to a ledge of a given height. The elastic hinge is a pneumatic spring moving between the guides of the design form. The force characteristic of the hinge depends on the shape of the guides and on the pressure in the air spring. The calculation of the circular shapes of the guides of the elastic hinge is given. The values of the forces arising between the pneumatic spring and the guides are determined. [ABSTRACT FROM AUTHOR]

Soft transportation devices with high flexibility, good stability, and quick controllability have attracted increasing attention. However, a smart soft transportation device with tactile perception and a non-contact actuating mode remains a challenge. This work reports a magnetic soft pipeline (MSP) composed of sensor film, a magnetorheological elastomer (MRE) cavity pipeline, and heater film, which can not only respond well to tactile compression stimuli but also be transported by magnetic actuation. Notably, the sensor film was integrated on the upper surface of an MRE pipeline, and the relative resistance change (∆R/R0) of the MSP was maintained at 55.8% under 2.2 mm compression displacement during 4000 loading cycles. Moreover, the heater film was integrated on the lower surface of the MRE pipeline, which endows the MSP with an electrothermal heating characteristic. The temperature of the MSP can be increased from 26.7 °C to 38.1 °C within 1 min under 0.6 V. Furthermore, the MSP was attracted and deformed under the magnetic field, and the ∆R/R0 of the MSP reached 69.1% under application of a 165 mT magnetic field density. Benefiting from the excellent perception and magnetic deformation performances, the magnetic actuate transportation of the MSP with self-sensing was successfully achieved. This multi-functional soft pipeline integrated with in situ self-sensing, electrothermal heating, and non-contact magnetic actuating transportation performance possess high potential in smart flexible electronic devices. [ABSTRACT FROM AUTHOR]

Objectives. This study conducted a comparative analysis of two catastrophic pipeline accidents in China in order to identify some common mistakes and lessons learned to prevent similar accidents. Methods. The 24Model was used in this study, which provides a universal pathway for accident analysis from the individual level to the organizational level. Results. There were similarities between the two cases in the aspects of the occurrence, development, emergency and causation at different levels: both were caused by leaks of pipelines and evolved into multiple explosions during emergency response; both leaks were caused by the corrosion of pipelines in the confined space of a damp or salt-spray environment; both were classified as 'responsibility accidents', and unsafe acts, such as the failure to identify hidden hazards of pipelines that were the direct cause of accidents, reflected the shortcomings of individual safety habitual behaviour in terms of knowledge, awareness, habits and psychology; weaknesses in the organizational management mainly concerned hazard identification, pipeline maintenance, emergency disposal, etc.; and there is not a good safety climate within the organization. Conclusions. Organizations should develop a closed-loop management system and strengthen the construction of safety culture, and the government should supervise the implementation of procedures. [ABSTRACT FROM AUTHOR]

Cracks in transport pipelines significantly impact their structural safety, making pipeline fracture damage a major concern. While experimental tests can study crack growth, their setup and costs are substantial. To address this, our work involves parametric analyses to investigate the effects of initial crack length, load types and sizes, and pipe wall thickness on the crack tip stress field. The finite element model is established according to the actual operation, and the crack defects of the pipe are established by the extended finite element method (XFEM). The crack tip variation is studied by extracting the von Mises stress and strain at the crack tip. When the crack propagates, the stress field at the crack tip will fluctuate in a certain range. The relationship between stress field fluctuation and crack propagation was studied by changing the XFEM crack growth for comparative analysis. Utilizing 429 numerical results obtained from a parametric numerical model implemented with Python and Abaqus, we establish a back propagation (BP) neural network prediction model to forecast the stress field at the crack tip. The relative errors between the numerical results and the predictions by our model remain below 5%. In conclusion, our proposed approach for analyzing pipeline fracture under multiple loads proves valuable for pipeline safety assessment, and it offers useful insights for evaluating the suitability of transportation pipelines. [ABSTRACT FROM AUTHOR]

This review article provides a comprehensive overview of the fundamentals, modelling approaches, experimental studies, and challenges associated with hydrogen gas flow in pipelines. It elucidates key aspects of hydrogen gas flow, including density, compressibility factor, and other relevant properties crucial for understanding its behavior in pipelines. Equations of state are discussed in detail, highlighting their importance in accurately modeling hydrogen gas flow. In the subsequent sections, one-dimensional and three-dimensional modelling techniques for gas distribution networks and localized flow involving critical components are explored. Emphasis is placed on transient flow, friction losses, and leakage characteristics, shedding light on the complexities of hydrogen pipeline transportation. Experimental studies investigating hydrogen pipeline transportation dynamics are outlined, focusing on the impact of leakage on surrounding environments and safety parameters. The challenges and solutions associated with repurposing natural gas pipelines for hydrogen transport are discussed, along with the influence of pipeline material on hydrogen transportation. Identified research gaps underscore the need for further investigation into areas such as transient flow behavior, leakage mitigation strategies, and the development of advanced modelling techniques. Future perspectives address the growing demand for hydrogen as a clean energy carrier and the evolving landscape of hydrogen-based energy systems. [Display omitted] • Hydrogen gas characteristics are useful to model flow in pipelines. • Flammability, embrittlement, and leak risks associated with hydrogen pose challenges in transportation. • Temperature variation and pressure drop across critical components are important aspects of pipeline design. [ABSTRACT FROM AUTHOR]

The flowability and mechanical properties are increasingly crucial in the filling process of deep metal mines with mining depths exceeding 1000 m. The rheological properties of filling slurry in the pipeline were analyzed through rheological tests, L-tube self-flow tests, and semi-industrial loop tests. The results revealed that with an increase in the cement-to-tailings mass ratio (c/t ratio) and mass concentration, the slurry exhibited a higher flow resistance and decreased stowing gradient. During slurry transportation, the pressure loss in the straight pipe was positively correlated with the slurry flow rate, c/t ratio, and mass concentration. A uniaxial compressive strength (UCS) test was conducted to analyze the mechanical properties of the cemented paste backfill containing BMC (CCPB) in both standard and deep-underground curing environments. The UCS of the CCPB showed an increasing trend with the rise in curing age, mass concentration, and the c/t ratio. The comprehensive analysis concluded that when the c/t ratio is 1:4, and the mass concentration is approximately 74%, and parameters such as the slump, bleeding rate, and flowability of the filling slurry meet the criteria for conveying and goaf filling, resulting in a high-strength filling body. [ABSTRACT FROM AUTHOR]

Lipid trafficking is critical for the biogenesis and expansion of organelle membranes. Lipid transport proteins (LTPs) have been proposed to facilitate lipid transport at contact sites between organelles. Despite the fundamental importance of LTPs in cell physiology, our knowledge on the mechanisms of interorganelle lipid distribution remains poor due to the scarcity of assays to monitor lipid flux in vivo. In this review, we highlight the recent development of a versatile method named METALIC (Mass tagging‐Enabled Tracking of Lipids in Cells), which uses a combination of enzymatic mass tagging and mass spectrometry to track lipid flux between organelles inside living cells. We discuss the methodology, its distinct advantages, limitations as well as its potential to unearth the pipelines of lipid transport and LTP function in vivo. [ABSTRACT FROM AUTHOR]

Street View Images (SVI) are a common source of valuable data for researchers. Researchers have used SVI data for estimating pedestrian volumes, demographic surveillance, and to better understand built and natural environments in cityscapes. However, the most common source of publicly available SVI data is Google Street View. Google Street View images are collected infrequently, making temporal analysis challenging, especially in low population density areas. Our main contribution is the development of an open-source data pipeline for processing 360-degree video recorded from a car-mounted camera. The video data is used to generate SVIs, which then can be used as an input for longitudinal analysis. We demonstrate the use of the pipeline by collecting an SVI dataset over a 38-month longitudinal survey of Seattle, WA, USA during the COVID-19 pandemic. The output of our pipeline is validated through statistical analyses of pedestrian traffic in the images. We confirm known results in the literature and provide new insights into outdoor pedestrian traffic patterns. This study demonstrates the feasibility and value of collecting and using SVI for research purposes beyond what is possible with currently available SVI data. Our methods and dataset represent a first of its kind longitudinal collection and application of SVI data for research purposes. Limitations and future improvements to the data pipeline and case study are also discussed. [ABSTRACT FROM AUTHOR]

The global reliance on oil and gas pipelines for energy transportation is increasing. As the pioneering review in the field of ultrasonic defect detection for oil and gas pipelines based on bibliometric methods, this study employs visual analysis to identify the most influential countries, academic institutions, and journals in this domain. Through cluster analysis, it determines the primary trends, research hotspots, and future directions in this critical field. Starting from the current global industrial ultrasonic in-line inspection (ILI) detection level, this paper provides a flowchart for selecting detection methods and a table for defect comparison, detailing the comparative performance limits of different detection devices. It offers a comprehensive perspective on the latest ultrasonic pipeline detection technology from laboratory experiments to industrial practice. [ABSTRACT FROM AUTHOR]

The use of hydrogen-blended natural gas presents an efficacious pathway toward the rapid, large-scale implementation of hydrogen energy, with pipeline transportation being the principal method of conveyance. However, pipeline materials are susceptible to hydrogen embrittlement in high-pressure hydrogen environments. Natural gas contains various impurity gases that can either exacerbate or mitigate sensitivity to hydrogen embrittlement. In this study, we analyzed the mechanisms through which multiple impurity gases could affect the hydrogen embrittlement behavior of pipeline steel. We examined the effects of O2 and CO2 on the hydrogen embrittlement behavior of L360 pipeline steel through a series of fatigue crack growth tests conducted in various environments. We analyzed the fracture surfaces and assessed the fracture mechanisms involved. We discovered that CO2 promoted the hydrogen embrittlement of the material, whereas O2 inhibited it. O2 mitigated the enhancing effect of CO2 when both gases were mixed with hydrogen. As the fatigue crack growth rate increased, the influence of impurity gases on the hydrogen embrittlement of the material diminished. [ABSTRACT FROM AUTHOR]

Coal gangue, the primary solid waste generated during the coal mining process, is typically disposed of on the surface, where it gradually accumulates to form gangue piles that significantly contaminate the surrounding environment. Filling technology has been widely employed for the safe and efficient disposal of coal gangue due to its sustainability, safety, and efficiency. However, there is still a lack of theoretical research on the concentration of gangue slurry in long-distance filling pipeline transportation. Therefore, a calculation model of the ultra-long-distance transportable concentration of coal gangue slurry with different grades was constructed based on the static anti-segregation performance and Bingham model. In addition, the relevant parameters of the calculation model of the ultra-long-distance transportable concentration of coal gangue slurry in this mine were determined using the 8 km pipeline transport of coal gangue slurry in one mine as the technical background. It was subsequently demonstrated that the yield stress, plastic viscosity, and mass concentration of the various grades of gangue slurry in this mine exhibit an increasing exponential function, while the slurry density and mass concentration exhibit an increasing linear function, and the mass concentration and actual flow rate correspond to a quadratic polynomial increment. Finally, the minimum and maximum concentrations for different grades of gangue slurry that can be transported over long distances in this mine were determined. This work provides theoretical and practical guidance on how to select the concentration of gangue slurry for long-distance pipeline transport. [ABSTRACT FROM AUTHOR]

The pipeline transportation of iron ore slurry (IOS) is an eco-friendly alternate mode to transport the raw materials to longer distance and reduce the transportation network congestion problems. Proper selection of surfactant could modify mineral's viscosity, dispersion and wetting characteristics effectively as may be desired, which may further be monitored. A surfactant alters surface characteristics after being adsorbed onto minerals by altering the interfacial behaviour. This work is first report of the influence of a biosurfactant sourced from Aloe barbadensis Miller on the rheological behaviour of a high-grade iron ore (IO) sample at 45--72% by mass slurry concentrations range. The observed rheological parameters confirmed the non-Newtonian flow behaviour of the slurry. The collected IO and dried IOS samples were subjected to UV-Vis, XRF, PSD, XRD, SEM and EDS analyses. Experimental rheological data at varying concentrations was tested on various models to ascertain the best-fit rheological model for IOS transport. The Bingham model was found to be the most suitable to model the rheology of IOS. Experimental rheological behaviour of IOS was found to be linear with the yield stress. The study shall help to ascertain the suitability of a biosurfactant to stabilise high grade iron ores for pipeline transportation. [ABSTRACT FROM AUTHOR]