Liquefied Natural Gas Research Articles

Gas Pathing: Improved Greenhouse Gas Emission Estimates of Liquefied Natural Gas Exports through Enhanced Supply Chain Resolution

Gas Pathing: Improved Greenhouse Gas Emission Estimates of Liquefied Natural Gas Exports through Enhanced Supply Chain Resolution

Comparison of Carbon-Dioxide Emissions of Diesel and LNG Heavy-Duty Trucks in Test Track Environment

Environmental protection and greenhouse gas (GHG) emissions are getting increasingly high priority in the area of mobility. Several regulations, goals and projects have been published in recent years that clearly encourage the reduction of carbon dioxide (CO2) emission, the adoption of green alternatives and the use of renewable energy sources. The study compares CO2 emissions between conventional diesel and liquefied natural gas (LNG) heavy-duty vehicles (HDVs), and furthermore investigates the main influencing factors of GHG emissions. This study was carried out in a test–track environment, which supported the perfect reproducibility of the tests with minimum external influencing factors, allowing different types of measurements. At the results level, our primary objective was to collect and evaluate consumption and emission values using statistical methods, in terms of correlations, relationships and impact assessment. In this research, we recorded CO2 and pollutant emission values indirectly via the fleet management system (FMS) using controller area network (CAN) messages. Correlation, regression and statistical analyses were used to investigate the factors influencing fuel consumption and emissions. Our scientific work is a unique study in the field of HDVs, as the measurements were performed on the test track level, which provide accuracy for emission differences. The results of the project clearly show that gas technology can contribute to reducing GHG emissions of HDVs, and LNG provides a reliable alternative way forward for long-distance transportation, especially in areas of Europe where filling stations are already available.

Corrosion resistance in LNG plant design: Engineering lessons for future energy projects

Corrosion resistance is a critical consideration in the design and operation of liquefied natural gas (LNG) plants, where harsh environmental conditions and aggressive chemicals can significantly impact asset integrity and safety. This paper explores engineering lessons learned from past LNG projects, emphasizing the importance of corrosion management strategies to enhance the longevity and reliability of energy infrastructure. The study highlights key factors contributing to corrosion in LNG facilities, including materials selection, environmental exposure, and operational practices. By employing advanced materials such as corrosion-resistant alloys and coatings, engineers can mitigate corrosion risks, leading to reduced maintenance costs and extended equipment lifespan. The paper examines successful case studies where proactive corrosion management has been implemented, showcasing innovative engineering solutions such as cathodic protection, corrosion monitoring systems, and design modifications that enhance resistance to corrosion-related failures. Furthermore, it addresses the role of regular inspections, predictive maintenance, and risk-based approaches in identifying potential corrosion issues before they escalate into significant problems. As LNG plants continue to proliferate globally, the integration of corrosion resistance into design and operational frameworks becomes increasingly vital. This paper also discusses emerging technologies and materials that hold promise for improving corrosion resistance, including nanotechnology and smart coatings that provide real-time monitoring capabilities. By learning from past projects and embracing a proactive approach to corrosion management, future energy projects can enhance safety, reduce operational risks, and achieve greater sustainability in their operations. Ultimately, the lessons derived from this research will contribute to developing best practices for designing and operating LNG plants and other energy facilities, ensuring that they meet the challenges of a rapidly evolving energy landscape.

Optimization of the Thermokinetic Method for the Control of Weld Decay in AISI 304L and AISI 316L Stainless Steel Weldment

This study investigates the control of weld decay in AISI 304L/316L alloy weldments for liquefied natural gas (LNG) and cryogenic environments using the Tungsten Inert Gas (TIG) welding technique. Weldment samples were thermokinetically treated at 1050, 1100, and 1150°C and cooled in five mediums: Water, Salt, Natural Air, Salt with annealing, and Water with annealing, to retain carbon and chromium in solid solution at approximately 30°C. Furthermore, evaluation methods based on metallography i.e. optical microscopy (OM), Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDX), Wear Test (i.e. wear rate and wear track) and electrochemical corrosion potential measurements were adopted. An experimental design table was developed using the design expert software 13.0. This helped develop a predictive mathematical model for ascertaining the optimum operating service conditions of the material. From the results, the optical microscopy analysis revealed that the control sample exhibited a more irregular pattern than others. Results showed that the control sample had a more irregular structure, while air-cooled samples exhibited smoother surfaces, indicating better bonding. SEM revealed a coarse surface with uneven particle distribution post-heat application. The predominant elements were Iron (Fe), Chromium (Cr), and Nickel (Ni). Corrosion potential varied between -0.5 to 0.15 V, demonstrating wave-like behaviour over time. Wear analysis indicated that lower coefficients of friction correlate with better wear resistance. Finally, response surface methodology (RSM) revealed that increasing temperature proportionally increased yield and corrosion rates. While the identified optimal values for Temperature are (1112.68°C), Material (316L), and Quenching Medium (SQ+SA), resulting in specific values such as Wear Rate (5.76896E-06), Coefficient of friction (0.224254), Corrosion Rate (0.395566), and Weight of Heat-Treated Sample (14.7797). The study enhances understanding of the mechanisms affecting welding and contributes to optimizing welding procedures for improved mechanical properties and corrosion resistance.

Numerical Modeling and Experimental Validation of Icing Phenomena on the External Surface of a U-Bend Tube

The regasification of liquefied natural gas (LNG) is a crucial process that involves certain challenges created by the low temperature of LNG and the risk of ice formation on the external surfaces of the tubes of heat exchangers, which can hinder heat transfer and increase flow resistance. This study presents a numerical model for ice formation on the external surface of the U-bend tube of shell-and-tube heat exchangers. The numerical model has been further enhanced by applying a custom user-defined function. The numerical results were validated using experimental data and demonstrated excellent predictive capability, particularly for the surface temperature of the tubes and the thickness of the ice layer. Hence, this model can reliably capture the overall behavior of the ice formation on the external surfaces of the tubes of shell-and-tube heat exchangers. By highlighting the importance of maintaining stable heat transfer conditions to prevent freezing, this study offers valuable insights that can guide the optimization of heat exchanger designs for LNG regasification.

Modeling of Liquefied Natural Gas Cold Power Generation for Access to the Distribution Grid

Cold energy generation is an important part of liquefied natural gas (LNG) cold energy cascade utilization, and existing studies lack a specific descriptive model for LNG cold energy transmission to the AC subgrid. Therefore, this paper proposes a descriptive model for the grid-connected process of cold energy generation at LNG stations. First, the expansion kinetic energy transfer of the intermediate work mass is derived and analyzed in the LNG unipolar Rankine cycle structure, the mathematical relationship between the turbine output mechanical power and the variation in the work mass flow rate and pressure is established, and the variations in the LNG heat exchanger temperature difference, seawater flow rate, and the turbine temperature difference in the cycle system are investigated. Secondly, based on the fifth-order equation of state of the synchronous generator, the expressions of its electromagnetic power, output AC frequency, and voltage were analyzed. Finally, the average equivalent models of the machine-side and grid-side converters are established using a direct-fed grid-connected structure, thus forming a descriptive model of the overall drive process. The ORC model is built in Aspen HYSIS to obtain the time series expression of the torque output of the turbine; based on the ORC output torque, the permanent magnet synchronous generator (PMGSG) as well as the direct-fed grid-connected structure are built in MATLAB/Simulink, and the active power and current outputs of the grid-following-type voltage vector control method and the grid-forming-type power-angle synchronous control method are also verified.

Numerical analysis of coupling effect between sloshing and motion responses of a KCS in uni- and bi-directional waves

The seakeeping behaviour can be severely affected by the coupling between sloshing and ship motions in waves. The sloshing behaviour of liquid-loaded ships in bi-directional waves differs significantly from that in uni-directional waves. Given that ships operate in short-crested or multi-directional waves during their whole service period, it is significant to gain a deeper understanding of the effect of wave directionality on the coupling between sloshing and ship motions. In this study, a KRISO container ship (KCS) model with type-B liquefied natural gas (LNG) cargo tanks is adopted for coupling analysis. The 2D long-crested regular wave is adopted as an uni-directional wave, and three dimensional (3-D) cross wave is adopted as a bi-directional wave. The computational fluid dynamics (CFD) method is applied for the sloshing and seakeeping simulation of the ship model in different wave fields. The differences in wave elevation, sloshing forces, and coupling effects between ship motions and sloshing are studied in these two wave fields by adjusting control parameters such as ship heading angle and filling ratio. The comparative results indicate that sloshing behaviour and coupled motion responses in cross waves should be paid enough attention during ship design and evaluation.

EU Methane Regulation and its impact on LNG imports

Abstract The EU Methane Regulation entered into force on 4 August 2024. It creates rules and obligations on measurement-based Monitoring, Reporting, and Verification of methane emissions of relevant activities, and on Leak Detection and Repair, and introduces limits on routine venting and flaring within the European Union (EU). In addition, and importantly for this article, it creates the first import-related requirements on methane emissions for imported fuels globally. This article will focus on the impact of the Methane Regulation on Liquified Natural Gas (LNG) imports into the EU. In this respect, the Methane Regulation creates far-reaching and difficult-to-implement obligations. The concerns for the LNG industry and imports into the EU are that (i) many of the central rules are not set out in the Methane Regulation and will be provided in the years to come and (ii) some of the key concepts and key provisions lack clarity and are open to various interpretations. As we will discuss in detail, the uncertainty created by the Methane Regulation will make contract negotiations more difficult and will negatively affect the security of gas supply within the EU.

Heuristic algorithm for calculating the component composition of recombination gas without an adapted equation of state

Background. To conduct laboratory research of projects of gas enhanced oil recovery methods, a large volume of reservoir system is required. Often its replenishment by depth and/or separator samples is not economically feasible. Therefore, the task of fluid recombination from wellhead liquid sample and natural gas simulator arises. Objective. To calculate the component composition of recombination gas under the conditions of the task. Materials and methods. The heuristic calculation algorithm uses the tools of: modeling, inverse problems of physics, set theory, mathematical programming. Special focus is given to its empirical and theoretical justification. Results. The paper considers the limitations of the thermodynamic method. The conditions of the problem to be solved are outlined and justified. The applied algorithm of the solution is formulated and derived. The efficiency of the algorithm for oil systems is experimentally confirmed. Conclusions. The work will be of interest for specialists in the field of laboratory research projects of gas enhanced oil recovery methods. The issues of improving the accuracy of the applied algorithm and its further development are still under discussion.

Study on Hydroelastic Responses of Membrane-Type LNG Cargo Containment Structure under Impulsive Sloshing Loads of Different Media

Owing to the increasing g lobal demand for natural gas, the construction of liquefied natural gas (LNG) carriers has become a key trend in the shipbuilding market. In the design of membrane-type LNG carriers, a sloshing analysis is crucial for cargo containment systems (CCSs). In this study, structural responses due to impulsive sloshing loads were observed, including the effects of hydroelasticity and the test medium. To this end, the structural responses were first observed with and without hydroelastic coupling between the liquid and structure. When fluid–structure coupling is considered, a finite element analysis is performed for the integrated structure of the hull and CCS. This method was then applied to evaluate the capacity and safety of the inner hull structures of actual LNG vessels in cases where different sloshing pressures occurred owing to the different liquid–gas media. The structural capacity was evaluated using the utilization factor (UT). The results confirm that the effects of the hydroelasticity, density ratio, and phase transition of the experimental medium are essential for the evaluation of the structural responses of LNG CCSs.

Research on Electromagnetic Performance and Rotor Eddy Current Loss Suppression of Ultra‐Low Temperature and High‐Speed Permanent Magnet Motor Materials for LNG Pumps

AbstractThere is no unified material selection principle for ultra‐low temperature and high‐speed permanent magnet motors used in liquefied natural gas (LNG) pumps, and high rotor eddy current losses can easily lead to vaporization of the transported LNG. This article first studies the electromagnetic performance of motor structural component materials at room temperature and ultra‐low temperature environments, and proposes the material selection principles for this type of motor. Based on the experimental measurement results of material electromagnetic performance, the loss characteristics of motors under ultra‐low temperature and room temperature environments were compared. Based on the mechanism of rotor eddy current loss and considering the influence of environmental temperature on the material properties of motors, three optimization methods for rotor eddy current loss are proposed. The impact of different suppression measures on rotor eddy current loss is revealed. The suppression of magnetic conduction harmonics can be achieved by opening stator auxiliary slots and optimizing their size and position. High conductivity metal shielding layers are used and their materials and sizes are optimized, And the use of magnetic slot wedges can simultaneously suppress three types of harmonics. Finally, the suppression principles of different optimization methods on rotor eddy current losses were analyzed, and the optimization effects and advantages and disadvantages of different methods were discussed, providing theoretical reference for the optimization design of high‐speed permanent magnet motors operating in ultra‐low temperature environments. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.

Performance analysis and multi-objective optimization for an integrated air separation, power generation, refrigeration and ice thermal storage system based on the LNG cold energy utilization

Against the backdrop of escalating resource depletion and the urgent quest for alternative sources, liquefied natural gas (LNG) is increasingly gaining prominence as a sustainable solution, particularly in refrigeration applications. However, its underutilization results in wasted resources. To efficiently harness the released cold energy from LNG gasification, this study proposes an integrated system comprising air separation, power generation, refrigeration, and ice thermal storage. The system undergoes optimization using the non-dominated sorting genetic algorithm II (NSGA-II) to determine the optimal operating parameters. The optimized system is comprehensively analyzed from energy, exergy, economic, and environmental perspectives. Results show that the system, with a 70t/h LNG capacity, achieves an energy efficiency of 42.52% and an exergy efficiency of 48.09%. Economically, the system incurs a cost of approximately 0.0711 $/kWh and can mitigate over 1.4504*107kg of CO2 emissions. Compared to traditional LNG utilization systems, the integrated system demonstrates a 22.32% improvement in energy efficiency, a 7.69% enhancement in exergy efficiency, and a cost reduction of 0.0049 $/kWh. In summary, this technologically advanced and economically viable system offers a significant alternative to optimize LNG cold energy utilization.

A knowledge graph-based inspection items recommendation method for port state control inspection of LNG carriers

The safe navigation and operation of Liquified natural gas (LNG) carriers is crucial in maritime transportation. The Port State Control (PSC) inspection is the primary method for identifying deficiencies in vessels. Different from other vessels, the PSC inspection of LNG carriers requires knowledge of specialized transport equipment. Therefore, effective management of inspection knowledge and precise targeting of inspection items are particularly crucial. Knowledge graph is an efficient way to manage knowledge in the context of artificial intelligence. In this study, an LNG carrier PSC inspection knowledge graph is constructed for fusing multisource knowledge data from PSC inspection. Additionally, a knowledge graph-based recommendation model, namely the improved knowledge graph convolutional network combined with pretrained translation embedding (PT-KGCN), is developed to recommend inspection items and knowledge. The PT-KGCN model first carries out knowledge graph embedding. It then predicts possible deficiencies on the basis of historical PSC inspection data. Finally, it recommends inspection items by correlating the predicted deficiencies with knowledge from the knowledge graph. The results show that more than 87% of defective items in historical data are correctly predicted. The research findings can provide ideas for the practical application of knowledge data in the inspection fields.

Systematic experiment on adsorption, separation and regeneration of X zeolites for LNG production with different regeneration strategies: vacuum, purging, heating and hybrid combinations

This work experimentally investigated the adsorption, separation and regeneration properties of two X zeolites for natural gas deep decarbonization in liquified natural gas (LNG) production. The regeneration properties of JLOX500 and 13X were compared with relation to regeneration efficiency, energy consumption, desorption and adsorption rate of CO2, and other factors in different pathways: vacuum, purging, heating, and hybrid combinations. The results demonstrated that fresh JLOX500 with more cations and less binders had significantly greater CO2 adsorption capacities and larger separation factor (CO2/CH4) than those of fresh 13X, because of its larger micro-porosity and higher CO2 isosteric heat. Due to higher partial pressure, the adversely significant effect of CH4 competing adsorption against CO2 on adsorbent regeneration is confirmed. The flow rate increases of purge gas had no effects on regeneration efficiency for 13X when the CO2 concentration of desorbed gas reached to zero. Because of a greater cumulative pore volume, JLOX500 after sufficient regeneration has a larger CO2 adsorption capacity and a higher desorption rate of CO2 than 13X, which also makes it more efficient with regards to purge gas and energy consumption utilization. With 150 mL/min of purge gas, the energy consumptions for 13X and JLOX500 regenerated at 150 °C were 4.20 and 2.89 MJ/kg-CO2, respectively. The CH4 recovery relied on the regeneration efficiency of adsorbents, duration of adsorption, and the amount of purge gas used. Both X zeolites regenerated by purging (150 mL/min) or vacuuming at 1 kPa at 150°C could purify the feed to the CO2 content less than 50 ppm, but JLOX500 is more efficient with regards to the overall performance.

Life cycle greenhouse gas emissions and cost of energy transport from Saudi Arabia with conventional fuels and liquified natural gas

The International Maritime Organization has recently developed several regulations to reduce greenhouse gas (GHG) emissions. To meet these targets, ship builders and operators must either replace or upgrade the existing fleet with new decarbonized vessel technologies and/or switch to alternative fuels. The latter has been of interest, especially using liquified natural gas (LNG), among other alternative fuels, which can have lower emissions than conventional fuels. In Saudi Arabia in 2023, LNG was priced about 10 times lower than in Europe. In this study, Well-to-Wake life cycle GHG emissions and cost are calculated for a SUEZMAX tanker operating with three fuel options: high sulfur fuel oil, very low sulfur fuel oil and LNG. This is done for two different trips, for Saudi Arabia to Japan and Saudi Arabia to the Netherlands. Results show 11% and 12% life cycle GHG emissions reduction with LNG for trips to the Netherlands and Japan, respectively. From a sensitivity analysis of methane slip, LNG cost and anchoring time, the cost of GHG abatement for the LNG vessel varied from 171 United States dollars (USD) to –255 USD, and from 206 USD to –191 USD per ton of GHG, for the trip to the Netherlands and Japan, respectively.

Evaluating Environmental Impact and the Significance of Shipboard Carbon Capture and Storage for Emission Reduction in Maritime Sector

Abstract This study conducts Life Cycle Assessment (LCA) to evaluate the environmental impacts of Shipboard Carbon Capture & Storage (SCCS) across its entire lifecycle. It examines the full-spectrum carbon capture and storage effects from well-to-tank and tank-to-propeller for four types of marine fuels: Very Low Sulphur Fuel Oil (VLSFO), Marine Gas Oil (MGO), Liquefied Natural Gas (LNG), and Methanol. Additionally, the study examines the Energy Efficiency Existing Ship Index (EEXI) and Carbon Intensity Indicator (CII) of a current ocean-going container ship to quantify the potential benefits of SCCS in reducing ship carbon emissions. The results indicate that the application of SCCS can significantly reduce emissions from carbon-based fuels during ship operations. In particular, ships using VLSFO as fuel can achieve 61.0% reduction in emissions by installing SCCS. However, the application of SCCS leads to 7.8% increase in fuel consumption due to additional energy requirement. In addition, this study also found while fossil methanol reduces emissions during ship combustion, its life cycle emissions are 17.5%-19.6% higher than conventional fossil fuel due to production emissions. The overall SCCS has a positive impact on emission reduction for ships and is reflected in the improvements in EEXI and CII. With the implementation of SCCS, ships fuelled by VLSFO and MGO can remain compliant with IMO Greenhouse Gases emission strategy until 2030. For ships fuelled by LNG and Methanol, compliance can remain beyond 2030.

Efficiency Enhancement in the Liquefied Natural Gas Storage Scheme: Exploring Thermal Performance for Enhanced Energy Storage Solutions

ABSTRACTThe ongoing transition in the energy sector demands more efficient and reliable energy storage solutions. Our study addresses this need by optimizing the industrial process of liquefied natural gas (LNG) storage, focusing on enhancing thermal performance and energy efficiency. Leveraging a standard LNG storage design, we meticulously evaluated critical supporting variables, modeled key components, and conducted integrated cycle simulations. The primary goal was to minimize the volume of stored gas (achieving a reduction to approximately 1/600th of its gaseous state) while maintaining optimal storage conditions. Our methodology prioritizes insulation over pressure‐bearing factors in large‐scale tanks, aligning with the unique thermal challenges of LNG storage. Simulations were based on methane, which constitutes over 86% of the natural gas in the Middle East, ensuring relevance to the region's resources. The results are promising, with a compression stage reaching a maximum pressure of 2.377, an energy efficiency ratio of 60.71%, and a performance coefficient of 3.188. These findings offer a significant step forward in developing more effective and efficient LNG storage systems, contributing to the broader goal of sustainable energy management.

Study on resistance of basalt fiber reinforced concrete to sulfate erosion after cryogenic freeze-thaw cycles

This study aims to investigate the mechanical properties of concrete structures, such as liquefied natural gas (LNG) storage tanks, subjected to the effects of cryogenic freeze-thaw cycles and erosive environmental conditions. Mechanical properties of basalt fiber reinforced concrete (BFRC) with normal temperature (25 °C) and different temperature gradients (25 °C ∼ -80 °C, 25 °C ∼ -160 °C), fiber content (0 %, 0.1 %, 0.2 %), and sulfate erosion days (0, 60, 120) were determined. The morphology of the eroded specimens was examined, and the microstructural characteristics were investigated by scanning electron microscope (SEM). The findings revealed that the introduction of basalt fiber (BF) in the concrete significantly changes the failure mode following sulfate erosion, causing specimens to fail by ductile failure rather than brittle failure. Moreover, the mechanical properties of concrete specimens decreased significantly with increasing temperature gradients of freeze-thaw cycles. Under non-erosive conditions, the compressive strength of plain concrete after undergoing freeze-thaw cycles from 25 °C to -160 °C decreased by 22.4 % compared to plain concrete that did not undergo freeze-thaw cycles, and the tensile strength decreased by 32.5 %. Adding fibers increased the mechanical properties of specimens. Specially, after undergoing freeze-thaw cycles from 25 °C to -160 °C and being subjected to 120 days of sulfate erosion, compared with plain concrete, the compressive strength of specimens with 0.2 % fiber content increased by 20.6 %, the tensile strength increased by 37.8 %, while also increasing flexural toughness. In addition, the sulfate erosion days also had a considerable impact on the deterioration of the mechanical properties of specimens. Specially, after undergoing freeze-thaw cycles from 25 °C to -80 °C and being subjected to 120 days of erosion, the eroded specimen with 0.1 % fiber content, the compressive strength decreased by 10.9 %, the tensile strength decreased by 11.6 % compared to specimens that were not eroded, while also decreasing flexural toughness. Combined with the experimental results, the strength deterioration models of BFRC related to the sulfate erosion days and BF content were proposed at 25 °C, after freeze-thaw cycles from 25 °C to -80 °C, and after freeze-thaw cycles from 25 °C to -160 °C. The aim is to provide some data reference for the development and application of BFRC in cryogenic environments.

Black Sea Rising

_ Saipem’s flagship vessel Castorone was contracted to start work this summer on Turkey’s offshore deepwater Sakarya gas field while neighboring Romania prepared to enter Phase 2 of its Neptun Deep gas project. Blessed with some of the same source rock as the hydrocarbon-prolific Caspian Sea (they were one sea in the geologic past), the Black Sea has long been regarded as a frontier basin of great promise, but with unique challenges—earthquakes, sheer slopes plunging to 2200-m depths where sediments are unstable, its bottom-water harbors H2S instead of oxygen, and complex life is nowhere to be found. Straddling Europe and Asia, the Black Sea is surrounded by Turkey, Russia, and other remnants of the USSR and the czarist empire before it: Romania, Bulgaria, Ukraine, and Georgia. There is also only one way in and one way out, via Istanbul and the Bosphorus Strait whose width varies from 3.7 km (2.3 miles) to 750 m (2,450 ft). The Bosphorus has long been the southern export route for Russian (and Soviet) oil loaded on tankers at Novorossiysk for transport to the Mediterranean, and over years the Black Sea has become crisscrossed by gas pipelines, most notably the Blue Stream and TurkStream, which seemingly cemented Turkey’s role as a transit state and major consumer of Russian gas. Times, though, have changed. With energy security through diversity of supply now top of mind, Romania and Turkey are driving their own exploration and production projects to identify and develop deepwater gas reserves to supply domestic needs as they simultaneously strategize to become future exporters through such infrastructure as the Trans Anatolian Natural Gas Pipeline (TANAP) and liquified natural gas (LNG). Ukraine and Russia, meanwhile, are the wildcards in the region, considering that the largest deepwater deposits in the Black Sea are believed to lie in the unexplored waters of Ukraine. Neptun Deep To Position Romania as Largest EU Gas Producer In June 2023, 50/50 partners Austria’s OMV Petrom and Romanian state-owned Romgaz Black Sea Ltd. took a final investment decision (FID) to proceed with their $4.4-billion Neptun Deep gas project, which data and analytics provider Wood Mackenzie (Woodmac) notes, will make Romania the largest gas producer in the EU. Neptun Deep is the first deepwater development on the Romanian shelf which is part of the northwestern Black Sea Continental Shelf (Fig. 1). According to Woodmac, it was the EU’s largest upstream FID in 2023. With an estimated 100 Bcm in reserves, Neptun Deep aims to produce first gas in 2027 from two fields: the deepwater Domino gas field at 1000-m depth and the shallow-water Pelican Sud (South) at 120-m depth. The project’s 10 wells will tie back to an unmanned shallow-water platform and will deliver 8 Bcm/yr (775 Mcf/D) of gas at plateau for about 10 years (Fig. 2). Neptun Deep’s plateau output will boost OMV Petrom’s production mix to 70% gas from the current 50%, a goal the Austrian operator has set for itself by 2030.

Risk assessment of gas plume dispersion in bunkering of alternative fuel through validated computational fluid dynamics approach

Abstract Maritime decarbonization is crucial in fighting climate change. Adopting low-carbon alternative fuels could help reduce greenhouse gas (GHG) emissions by 50% by 2050 compared to 2008. While liquified natural gas (LNG) has gained a strong foothold in the maritime sector over the past decades, the trend is shifting toward adopting lower and zero-carbon hydrogen and its carriers, such as methanol and ammonia, as alternative fuels. Quantifying risks from accidental leakages during storage and transfer of these alternative fuels using numerical models is required and commonly adopted in industries. The process leverages multiple models and tools for risk assessments with different accuracy levels and costs ranging from integral models to Lagrangian techniques and Eulerian approaches such as computational fluid dynamics (CFD). Increasingly, CFD approaches are employed for near-field dispersion analysis to assess the risk of accidental leakages. Despite their high computational cost, CFD models offer better accuracy than integral and Lagrangian models. In this work, we developed a CFD-based framework as a quantitative tool for risk assessment purposes. Our framework aims to (1) offer finer gas dispersion resolution with a detailed representation of surrounding structures and geometries, (2) minimize reliance on assumptions and empirical models to capture flow dynamics and gas dispersions accurately, and (3) mitigate conservative estimates and over-design of safety measures. The framework was validated using experimental data from various field tests, including a recent one involving releasing cryogenic liquids into the atmosphere. After successfully validating and comparing with experiments and other available tools, the proposed framework investigated gas plume dispersion from accidental leakages during fuel bunkering operations in ship-to-ship and shore-to-ship scenarios. The data obtained from CFD simulations was subsequently utilized to construct a surrogate model for fast prediction of gas plume behavior under varying environmental conditions. This facilitated the development of an effective emergency response plan.