Oil And Gas Industry Research Articles

Selection and Sensitivity Analysis of Flare Piping Materials for the Onshore Hydrocarbon Industry

Selection and Sensitivity Analysis of Flare Piping Materials for the Onshore Hydrocarbon Industry

A multicriteria model to support the selection of inspection service providers based on the delay time model

AbstractThis paper proposes a multicriteria model based on the delay time concept and the FITradeoff method to support the choice of a service provider who inspects isolation valves, thereby enabling maintenance actions that have a strategic focus to be established for natural gas industries. We consider the possibility of errors of judgment (false negatives), thus allowing an approximation of reality to be made. In addition, the FITradeoff method is used to enable a decision‐maker to aggregate his/her preferences by taking account of more than one criterion simultaneously, even though the criteria generally conflict with each other. Furthermore, we undertake a numerical application to assess the practical implications. The model proved to be effective at supporting decision‐makers to select companies to provide periodic inspection services, which are often carried out under contracts. We have also evaluated how maintenance decisions change due to different decision‐makers' standards so as to obtain more appropriate procedures for maintenance actions. This has an impact on reducing the occurrence of failures and, consequently, reducing risks to people who live near the gas pipelines.

Corrosion Resistance of GMAW Duplex Stainless Steels Welds.

The hydrocarbon industry constantly requires a better understanding of stainless-steel welding metallurgy. Despite the fact that gas metal arc welding (GMAW) is one of the most commonly employed welding processes in the petrochemical industry, the process is characterized by the presence of a high number of variables to control in order to obtain components that are dimensionally repeatable and satisfy the functional requirements. In particular, corrosion is still a phenomenon that highly affects the performance of the exposed materials, and special attention must be paid when welding is applied. In this study, the real operating conditions of petrochemical industry were reproduced through an accelerated test in a corrosion reactor at 70 °C for 600 h, exposing robotic GMAW samples free of defects with suitable geometry. The results show that, even if duplex stainless steels are characterized for being more corrosion resistant than other stainless steels, under these conditions it was possible to identify microstructural damage. In detail was found that the corrosion properties were strongly related to the heat input during welding and that the best corrosion properties can be obtained with the higher heat input.

Present-Day In Situ Stress Analysis in Shale Reservoir of Haiba Block, Southern Sichuan Basin, South China

Natural gas from shale gas reservoirs has been an important contributor for reserve growth, deliverability construction, and profits growth in natural gas industry in the world. Hydraulic fracturing is commonly required in the shale gas commercial development, and thus understanding the present-day in situ stress field is greatly significant for the hydraulic fracturing and efficient development in shale gas reservoirs. However, there are no systematic investigations on the present-day in situ stress field in the Haiba Block from the Sichuan Basin, South China. In this study, the present-day in situ stress orientations and magnitudes in shale reservoir of Haiba Block are investigated based on the well interpretations from borehole image log and geomechanical modeling. Then, the effects of stresses on hydraulic fracturing, horizontal wells, and natural fracture reactivation were discussed. The results indicate that the horizontal maximum principal stress (SHmax) orientation is mainly in the NE-SW-trending, NW-SE-trending, and WNW-ESE-trending in the Haiba Block. The magnitudes of horizontal maximum and minimum principal stresses are 13.5 MPa~85.5 MPa and 2.8 MPa~31.6 MPa, respectively. In the Haiba Block, the differential stress is generally low in the northern part, which indicates that complex hydraulic fracture networks may be produced. While the natural fractures are generally stable under the present-day in situ stress field. When the increase of pore pressure gradient is about 30 KPa/m, nearly all natural fractures in the Longmaxi Formation may be reactivated. The results can provide the insights into a better understanding of the present-day in situ stress distribution so as to optimize perforation orientation, hydraulic fracturing design, and enhance gas production in shale gas reservoirs.

A Field Study of Corrosion and Its Control in an Oil Primary Distillation Unit

The internal corrosion process in refinery environments is one of the major problems faced by the hydrocarbon industry, where at least five types of internal corrosion are found in an oil primary distillation unit. This situation increases with the presence of high quantities of contaminants within the crude oil and the processed hydrocarbons. The best way to understand the internal corrosion is to know the parameters and components that affect it and apply protection to the metal exposed. This work offers alternatives on the knowledge of internal corrosion problems in refinery environments and highlight electrochemical treatments in oil primary distillation units, from materials selection to suitable chemical treatment dosage of corrosion inhibitors, neutralizers and other chemical compounds for materials protection.

Preliminary Test of Gas Wave Ejector in Coalbed Methane Well Site and Impact Analysis of Fluid Medium Characteristics on Its Pressure Port Design

Gas wave ejector (GWE) is an efficient energy conversion device which can recover and utilize excess pressure energy of high pressure fluid. It has significant application value in the sustainable development of energy resources, including the exploitation and transportation of natural gas. The first practical application test of GWE in the natural gas industry is completed in this study. The mechanisms and regulations of the effect of actual gas properties on the pressure port design of GWE were also investigated. The primary conclusions are as follows: the composition of working medium significantly affects the propagation velocity of pressure waves. The wave propagation velocity increases as methane purity (φCH4) rises. The equipment efficiency was decreased by up to 23% of the optimal value as a result of the variation in port position brought on by the increase in φCH4 from 0.7 to 1.0. The variation of working pressure ratio has a greater impact on the device performance than the pressure value when the pressure port design kept unchanged. The intake temperature fluctuation in the range of -30°C to 50°C has no obvious influence on the ideal port design. In the coal-bed methane well site industrial test, GWE accomplishes a recovery of low-pressure well by roughly 8.83 × 10 3 N m 3 / d , demonstrating its excellent ejection capacity. In addition, the variable speed test conducted under different working conditions shows that the equipment performance can be effectively enhanced by adjusting the rotation speed as the equipment structure remains unchanged with the changing working pressure/pressure ratio. In the field test range of this study, the increase of equipment ejection rate obtained by speed adjustment can rise up to 12% of the corresponding value at the designed rotation speed.

The wear behaviour of different metallic bond alloys tested in a modified B611-13 test in an acidic, neutral and alkaline media

The abrasive and adhesive wear behaviour of metallic bonds can be significantly affected by varying pH values of the attacking medium. However, the knowledge about the pH value influence on diamond impregnated bits used in core drilling industry is still limited. One recent publication shows the advantage of modifying a standard ASTM B611-13 test to investigate the abrasive and adhesive wear behaviour of a diamond segment bond material in a neutral regime (pH7). This study mainly focuses on the effects of a varying surrounding media on the tribological behaviour using an acidic, neutral and alkaline slurry. This emulates more aggressive conditions for the diamond segments used in mining as well as construction industry. The pH value at which such diamond segments operate can differ from pH2 up to a value of pH13. The present work studies the wear behaviour of two metallic bonds in a modified B611-13 arrangement at 4 m/s sliding speed and different pH values. The tested specimens are investigated with regard to their change in mass and microstructure at the sliding interface zone. The results reveal a significant influence of the pH value on the wear behaviour of the bond system.

Impact of Digital Industrialization on the Energy Industry Supply Chain: Evidence from the Natural Gas Industry in China

The global economy is moving into a new era characterized by digital and green development. To examine the impact of digital industrialization development on the energy supply chain, in relation to the sustainable development of China’s energy security, we discuss the nonlinear impact and transmission mechanism of digital industrialization on the supply chain of the energy industry using a panel threshold regression model based on sample data on the development of the provincial natural gas industry in China from 2006 to 2020. We found that there are multiple threshold effects of digital industrialization level development on energy supply chain length, and the results are statistically significant, i.e., digital industrialization development positively contributes to natural gas supply chain length after digital industrialization is raised to or crosses the critical threshold. Meanwhile, the heterogeneity analysis results show that there are differences in the impact of digital industrialization on the energy supply chain from sub-sectors, regional development differences, and different development periods. Therefore, we provide some factual support and experience for achieving the construction goal of “Digital China” and accelerating the digital reform of the energy supply chain as well as transforming and upgrading the economic structure.

Experiment and Simulation Research on Rock Damage Mechanism in Tooth Indentation

In the oil and gas drilling industry, cemented carbide teeth are one of the most widely used rock-breaking elements. In order to reveal the rock damage mechanism of tooth indentation, a series of tooth indentation experiments were conducted in this study, and an indentation simulation was also conducted as a supplement to the experiment. In the experiment, a new method to observe the inner damage status of the rock was put forward, i.e., utilizing the splitting action of the teeth to avoid unexpected rock damage that may affect the actual experiment results. The load-displacement curves and the damage status of the rock revealed that the wedge tooth was more efficient in fracturing and damaging the rock because the load requirement of the wedge tooth was lower, the narrow tooth crown generated larger specific stress in the rock; that rock-breaking advantage of the wedge tooth resulted from the occurrence of the compacted core and the tension stress generated by the core. According to the simulation results, the plastic strain in the intermediate area between the wedge teeth appeared more concentrated and increased faster, and the rock material beneath the wedge teeth was removed earlier than beneath the conical teeth, indicating that wedge teeth, disposed with proper spacing, can break rock more effectively than the conical teeth. The experiment and simulation results in this paper have proved the advantages of the wedge tooth in rock fracturing and damaging, which will provide technical support for the design and development for the drill bits applied in oil and gas drilling.

The Need for Gas Pipeline Capacity: Guidance (or not) from the Spire STL Experience

On December 15, 2022, the Federal Energy Regulatory Commission (FERC) issued a permanent certificate authorizing the Spire STL natural gas pipeline serving the St. Louis area to continue service operations. Spire STL had been on a legal roller‐coaster, wherein it received a FERC certificate in 2018, built and started operation of the 65‐mile pipeline in 2019, then in 2021 saw its certificate “vacated”—wiped out—by a U.S. Court of Appeals, essentially an order to cease operations. Then, during the white‐knuckled tail end of the ride, with the winter of 2021–2022 looming and potentially a loss of the natural gas supply and capacity at the last minute, Spire STL received an emergency/temporary authorization from FERC to continue operating while a new certificate application was being considered. The permanent certificate issued on December 15 should mean, absent another court reversal, that St. Louis may rely on the capacity for a long time. However, both the nature of FERC's decision and the implications for the rest of the natural gas industry need further exploration.

Semi-quantitative risk assessment of marine mammal oil exposure: A case study in the western Gulf of Mexico

Marine mammals are highly vulnerable to oil spills, although the effects at both individual and population levels are not fully understood. A first approximation to evaluate the possible consequences of oil spills on marine life is using ecological risk assessments, which are analytical tools used to assess the likelihood of adverse environmental effects due to exposure to stressors derived from human activities. We developed a semi-quantitative framework to evaluate the risk of oil spill exposure on marine mammals that combines the likelihood of exposure based on species-specific biological and ecological traits, and the feasibility of encounter, which considers not only the overlap between the distribution of the species and the total affected area by a spill but also considers the distribution of spilled oil within this area, thus reducing the uncertainty in the estimate. We applied our framework to assess the risk of exposure of eight cetaceans to scenarios of large heavy oil (API gravity<22) spills originating from three hypothetical deep-water wells in the western Gulf of Mexico. High habitat suitability areas obtained using the maximum entropy (MaxEnt) modeling approach were used as a proxy for the geographic regions where each species is likely to be distributed, and oil spill scenarios were generated using numerical models incorporating transport, dispersion, and oil degradation. The analysis allowed identifying those species for which there is a significant risk of exposure in each spill scenario. However, our results suggest that the risk does not appear to be high for any species under any scenario. The information generated by our risk assessment is key to developing management plans in those areas of the Gulf of Mexico where deep-water activities of the hydrocarbon industry are currently being developed or planned.

A Novel Approach for Active Surge Control in Multistage Centrifugal Compressor

Compressors are used in the hydrocarbon industry from upstream to downstream to boost the pressure required to transport gas into processing and transportation pipelines inside and toward processing facilities. Turbo-centrifugal compressors are subject to repetitive damages resulting from the manifestation phenomenon known as surge, observed as fluid flow reversal at low mass flows. Active surge control aims to increase the compressor operating region by allowing the compressor to operate at low mass flow in the naturally-unstable region of the compressor. Surge is avoided in the industry by forcing the operating point to the stable region of the compressor curve. Active surge control aims to control the surge phenomenon by extending the stable operating region. This work developed a novel model-based control approach for effective compression system active surge control on an automatic coupled recycle valve as a primary actuator. The feedback linearization technique is used to reduce the system complexity by providing a linear representation of the highly nonlinear system. A detailed description of the feedback linearization method for centrifugal compressors and a dual controller design was developed in this paper.

Strengths, weaknesses, and opportunities of local content policy, legal, and institutional framework in the upstream natural gas sector in Tanzania

Tanzania is expected to become a major exporter of liquefied natural gas (LNG) in the future, following the discovery of natural gas reserves totalling 57.25 trillion normal cubic feet (TCF). In Lindi, Tanzania, a proposal is being made to export two-train LNG, a US$ 30 billion liquefied natural gas (LNG) project. However, it's unclear whether the existing LCP will be enough to prevent Tanzania from following in the footsteps of other resource-rich African countries, such as Algeria, Egypt, Angola, the Democratic Republic of the Congo, and Somalia, which have all experienced resource-related wars, disputes, crises, and conflicts. Therefore, this paper critically assesses the strengths, weaknesses, and opportunities in the Tanzanian upstream natural gas sector's local content policy, legal, and institutional framework.A qualitative study was conducted utilising a SWOT analysis on local content policy, legal, and institutional framework on the national level. The authors used the SWOT (strengths, weaknesses, opportunities, and threats) analysis to conduct a narrative document review and literature review. The SWOT approach is well-structured and enables both descriptive and cross-sectional qualitative studies. In addition, the SWOT analysis helps draw a portrait of how challenging it is to establish and implement suitable policies, institutional frameworks, and regulations adapted to local needs.The study finds that Tanzania's legal, policy, and institutional framework for local content in the upstream natural gas industry offers various strengths and opportunities; it also has several weaknesses and threats that must be addressed. First, Tanzania's local content policy, regulatory, and institutional frameworks failed to consider the actual state of Tanzanian industry or indigenous Tanzanian firms' preparedness and industrial capacity. Second, Tanzania's local content is limited by a lack of government coordination with other oil and gas government agencies and other stakeholders. Prioritising local suppliers is part of the local content policy, which also eases evaluation criteria for local firms. The fundamental institutions at stake are the rule of law, bureaucratic quality, government corruption, and the risk of expropriation and contract repudiation. Finally, unregulated lobbying can lead to regulatory capture by special interests or limited policy options. These findings apply to any context and can be utilised by decision-makers, managers, experts, and other stakeholders to focus on significant concerns and identify areas that need to be addressed.

Salinity responses in 24 guar genotypes are linked to multigenic regulation explaining the complexity of tolerance mechanisms in planta

AbstractGuar (Cyamopsis tetragonoloba (L.) Taub.) is an economically important, drought‐tolerant legume crop affected by moderate to high salinity. Guar has various industrial applications, including gum extracted from seeds that is widely used in the oil and natural gas industries. In this investigation, we evaluated the salinity tolerance of different guar genotypes and their relation to genetic mechanisms regulating guar responses to salinity stress. We screened 24 guar genotypes in a greenhouse lysimeter system under control (electrical conductivity (EC) = 1.46 dS m−1) and high salinity (EC = 13.65 dS m−1) treatments. Both length and biomass of shoots were significantly affected by salinity compared to roots, indicating higher shoot than root sensitivity to salinity. Twenty‐four genotypes were classified based on salt tolerance index for each trait. Tissue ion analysis revealed that roots accumulated over 10‐fold higher Na than leaves, demonstrating that guar effectively regulated the root‐to‐shoot movement of Na+. However, higher Cl concentrations in leaves than roots indicated less regulatory control of Cl− movement. Based on the morphological traits and tissue ion analysis, six genotypes (PI 164486, PI 253186, PI 26152, PI 158125, PI 179926, and PI 263698) with different responses to salinity were selected for gene expression analysis. Expression patterns of different genes showed that a complex network of component traits, including Na+ exclusion, Cl− exclusion, and tissue tolerance, regulate salinity tolerance in guar. Hence, the genetic information about different component traits will benefit guar breeders in developing new varieties that are more tolerant to salinity than current ones.

Evolution of sediment gravity flows in response to early Carboniferous subduction and closure of the West Junggar Basin, China

This study describes and characterises the spatial distribution and evolution of Carboniferous deep-water sediment gravity flows and their associated deposits in the West Junggar region of north-western China. It uses a combination of outcrop sections, cores and seismic profiles to define nine lithofacies associated with a different sediment gravity flow types, including turbidity currents, debris flows, hyperpycnal flows and supercritical flows. The subduction and closure of the remnant West Junggar Ocean basin demonstrated variable palaeogeographical characteristics and configurations during different periods of the Carboniferous. Fossil assemblages and zircon dating data indicate that the target strata have completely recorded the evolution of the Western Junggar remnant ocean in the Carboniferous. The basin evolution is divided into the stable ocean basin stage, the slow subduction and filling stage and the fast subduction and filling stage. Active faulting and varying slope gradients affected the occurrence and types of sediment gravity flows during each stage. Tectonic and seismic activities associated with subduction caused continental slope instabilities and basinward transport of sediment by gravity flows with active faults on the continental slope triggering sediment gravity flows. At the beginning of subduction, the ability of gravity flows to transport coarse debris was limited owing to the shallow gradient of the continental slope. Sediment transport via gravity flows was dominated by sandy debris flows, muddy debris flows, turbidity currents and less frequent flood-controll3ed hyperpycnal flows. As the basin entered the fast subduction and filling stage, the slope gradient steepened and the frequency of active thrust faulting increased, which triggered high-density turbidity currents and supercritical flows. Additionally, the warm and humid paleoclimate led to the development of hyperpycnal flows during the fast-filling stage. This study demonstrates the importance of understanding the character and distribution of sediment gravity flows and associated deposits, especially, the implications for the hydrocarbon industry.

Detection, distinction, and quantification of pipeline surface and subsurface defects by DC magnetization scanning induction thermography

Pipelines are the backbone of the oil and natural gas industry. In order to guarantee its quality, DC magnetization scanning induction thermography (DCMSIT) is proposed to detect, distinguish and quantify the pipeline surface and subsurface defects. The exciting method, consisting of Helmholtz DC magnetization coils and a toroidal AC induction heating coil, is designed to adapt the pipeline’s annular shape and realize full coverage automatic detection. Under DC magnetization, surface and subsurface defects cause distorted permeability distribution in the skin layer relating to defect depth. Under AC magnetization, the distorted permeability produces abnormal thermal distribution, indicating the characteristics of defects. Based on the different thermal distributions in shapes and intensities of surface and subsurface defects, continuous wavelet transform (CWT) is used for thermal signal spatial-frequency analysis to distinguish surface and subsurface defects. The principle of the proposed method is analyzed based on Faraday’s law, Joule’s law, and thermal propagation. Then, finite element simulation is conducted to investigate magnetic permeability distribution for pipeline surface and subsurface defects with different depths. Finally, the DCMSIT system for pipelines is designed and developed to validate the proposed method. Experimental results show that the proposed method can evaluate pipeline surface and subsurface defects from 1.0 mm to 5.0 mm in depth.

Deformation behaviour and notch sensitivity of a super duplex stainless steel at different strain rates and temperatures

For the successful development of a structure, understanding of mechanical behaviour of the selected material is an important issue to prevent damage or accidents. Mechanics of the material failure depends on its chemical composition, heat treatment, grain size, strain rate, type of loadings etc. Apart from material properties, the performance of the structure is also affected by its geometry, crack/notch/hole/groove and manufacturing processes. In construction of offshore, marine, power plant and oil-gas industry structures, super duplex stainless steel is one of the suitable materials. Therefore, the objective of the paper is to study the deformation behaviour and notch sensitivity of a super duplex stainless steel, SDSS 2507 at different strain rates (0.0001–0.1s−1) and temperatures (25–200 °C) under tensile, compressive and flexural (three-point bending) loads. Heating rate and soaking time are 8 °C/min and 15 min respectively. Experiments are conducted on electromechanical universal testing machine using suitable fixtures. The steel is found positive sensitive to the strain rate and temperature, where the phenomenon of dynamic strain ageing (DSA) is observed during thermal effects. Fractography analysis is correlated with the typical stress-strain curves. Heat treatment (heating rate 12 °C/min and soaking time 1–3 h) enhances the tensile strength of the steel upto 18% at 400–600 °C for strain rate 0.001s−1, whereas at 700 °C, the strength decreases by 31% and the energy dissipation decreases by 88% due to its brittle behaviour. Notch profiles (C, U and V) on the flat tensile specimens of the steel decreases the energy dissipation by nearly 67–74% at 0.001s−1. Ductile-brittle transition temperature exists between 600℃-700℃ in tensile tests. Compression tests are conducted for varying geometries of cylindrical specimens. Flexural behaviour of the steel is investigated for 120–160 mm span lengths and flat-transverse orientations. Existing material models (Cowper-Symonds and Johnson-Cook) are evaluated.

Spatial connection network characteristics and development trend forecast of natural gas industry's sustainable development resilience in China.

Objectively recognizing and improving the sustainable development resilience of China's natural gas industry will help achieve the low-carbon transformation goal of China's energy system. Taking 31 Chinese provinces as the research area, this paper measures the sustainable development resilience (SDR) of China's natural gas industry based on the Drive-Pressure-State-Impact-Response (DPSIR) model and entropy method, and integrates the gravity correction model and social network analysis methods to identify the spatial linkages and network patterns among core regions, and further explores the development trend of the SDR of China's natural gas industry using grey model (GM(1,1)) moderated by a variable-weight buffer operator. The results show that: (1) There are significant regional differences in the SDR of the natural gas industry across Chinese provinces. The SDR is a high priority in Shanghai, Shaanxi, Sichuan, Xinjiang, Guangdong and Shandong, while it is low major in Tibet, Yunnan, Guangxi, Guizhou and Ningxia. (2) The spatial connection network density is low in China's natural gas industry, and the network correlation between provinces is poor. In detail, Jiangsu, Guangdong and Shandong are the core of the entire network and the connection lines between provinces are mainly basic in the whole region with poor connection strength, but there is a trend for the better. (3) The changing trend is significantly different in the SDR of Chinese provinces, and the prediction results show a trend of "polarization" in the SDR index of the provinces in the resource endowment area.

The pathway to the natural gas industry: Financial development, coal consumption, and carbon dioxide emissions in P.R. China.

This paper revisits the causal links between financial development, coal consumption, and CO2 emissions in P.R. China over the 1977-2017 period to validate the development of its natural gas industry. It uses a Bootstrap ARDL bound test with structural breaks to establish stationarity, short- and long-run dynamics, and causality of the series. The results show there are no long-run relationships among these three variables, but a Granger causality test does indicate the presence of both a two-way Granger causality between coal consumption and CO2 emissions, and a one-way Granger causality running from financial development to both coal consumption and CO2 emissions. These results have important policy implications for the Chinese government's efforts to meet its commitment at the 75th UN General Assembly to achieve carbon neutrality. In that context, the promotion of its natural gas industry, including carbon pricing mechanisms and taxation schemes while enacting environmentally friendly energy abatement policies become a must.

Environmental pollutant hydrogen sulphide and its detection – A brief review

Many incidences of toxic exposure have been linked to H2S, particularly in the natural gas and petroleum industries, coke ovens, landfills, tanneries, wastewater treatment, and paper mills. The physiological consequences of H2S are always dependent on the concentration and duration of exposure. H2S concentrations can cause a variety of serious health concerns, including throat and eye related problems, impaired memory, and a loss of reasoning. To monitor and control the risk associated with this gas in real time, researchers have spent decades inventing sensors with adequate/good/robust metrological properties and strong stability. From the standpoint of human and environmental health protection, this thorough analysis linked to the toxicity and harmful effects of H2S gas. In a range of sensor devices, nano-structured materials-based sensors seem to be a good substitute for the most common options, like electrochemical and optical sensors. In this review, we evaluate the performance of various H2S sensors in terms of main operational factors such as sensing material, sensitivity, sensor stability, response time, response time, detection limits, concentration range, and selectivity.