Quantitative research of the liquid film characteristics in upward vertical gas, oil and water flows

The study of liquid film characteristics in multiphase flow is a very important research topic, however,the characteristics of the liquid film around Taylor bubble structure in gas, oil and water three-phase flow are not clear. In the present study, a novel liquid film sensor is applied to measure the distributed signals of the liquid film in three-phase flow. Based on the liquid film signals, the liquid film characteristics including the structural characteristics and the nonlinear dynamics characteristics in three-phase flows are investigated for the first time. The structural characteristics including the proportion, the appearance frequency and the thickness of the liquid film are obtained and the influences of the liquid and gas superficial velocities and the oil content on them are investigated. To investigate the nonlinear dynamics characteristics of the liquid film with the changing flow conditions, the entropy analysis is introduced to successfully uncover and quantify the dynamic complexity of the liquid film behavior.

Analysis of China＇s International Oil and Gas Cooperation Environment under the Belt and Road Initiative

China's Belt and Road Initiative has great significance for China's energy security and the economic development of the countries along the route of the Belt and Road Initiative. Focusing on oil and gas cooperation, the paper aims to define the political, economic, legal, and operational conditions required to facilitate the development of the Belt and Road Initiative by analyzing the advantages, disadvantages, opportunities and risks of China's current international oil and gas cooperation environment. This will help to drive China's international oil and gas partnerships and increase China's discourse power in the international oil and gas markets by exploring new approaches to improving regional communication mechanisms, financial cooperation frameworks, multilateral legal systems and overall strength of the enterprises in the oil and gas industry.

Hybrid Dissolved Gas-in-Oil Analysis Methods

Dissolved gas analysis is the most widely used diagnostic test in power transformers. The aim of this paper is to introduce the dissolved gas analysis (DGA) methods able to diagnose the transformer conditions. The faults cause the transformer oil, pressboard, and other insulating materials to decompose and generate gases, some of which dissolve in the oil. The results of DGA must be accurate if faults are to be diagnosed reliably. There are different established methods used in industry for interpreting DGA results. We will compare the result of IEEE Key Gas Methods and Rogers’ Ratios. The transformer conditions are evaluated by the Key Gas Method with total combustible gas method (TCGM) and then verified by the Rogers’ Ratios. As result, the aging pattern and trend of the power transformer deterioration can be determined. The 30 sample data from IEEE with known faults and dissolved gas concentrations were used as the basis of comparison.

Bohai crude oil identification by gas chromatogram fingerprinting quantitative analysis coupled with cluster analysis

By gas chromatogram, six crude oils fingerprinting distributed in four oilfields and four oil platforms were analyzed and the corre- sponding normal paraffin hydrocarbon （ including pristane and phytane） concentration was obtained by the internal standard methed. The normal paraffin hydrocarbon distribution patterns of six crude oils were built and compared. The cluster analysis on the normal paraffin hydrocarbon concentration was conducted for classification and some ratios of oils were used for oils comparison. The results indicated： there was a clear difference within different crude oils in different oil fields and a small difference between the crude oils in the same oil platform. The normal paraffin hydrocarbon distribution pattern and ratios, as well as the cluster analysis on the nomad paraffin hydrocarbon concentration can have a better differentiation result for the crude oils with small difference than the original gas chromatogram.

FCC coprocessing oil sands heavy gas oil and canola oil. 2. Gasoline hydrocarbon type analysis

This study set out to gain a deeper understanding of a fluid catalytic cracking(FCC)coprocessing approach using canola oil mixed with bitumen-derived heavy gas oil(HGO),for the production of partially-renewable gasoline,with respect to its composition and quality.The FCC coprocessing approach may provide an alternative solution to reducing the carbon footprint and to meet government regulatory demands for renewable transportation fuels.In this study,a mixture of 15 v%canola oil in HGO was catalytically cracked with a commercial equilibrium catalyst under typical FCC conditions.Cracking experiments were performed using a bench-scale Advanced Cracking Evaluation(ACE)unit at a fixed weight hourly space velocity of 8 h^(à1),490–530C,and catalyst/oil ratios of 4–12 g/g.The total liquid product samples were injected via an automatic sampler and a prefractionator(to removet254C)into a gas chromatographic system containing a series of columns,traps,and valves designed to separate each of the hydrocarbon types.The analyzer gives detailed hydrocarbon types of à200C gasoline,classified into paraffins,iso-paraffins,olefins,naphthenes,and aromatics by carbon number up to C_(11)(C_(10)for aromatics).For a feed cracked at a given temperature,the gasoline aromatics show the highest selectivity in terms of weight percent conversion,followed by saturated iso-paraffins,saturated naphthenes,unsaturated iso-paraffins,unsaturated naphthenes,unsaturated normal paraffins,and saturated normal paraffins.As conversion increases,both aromatics and saturated iso-paraffins increase monotonically at the expense of other components.Hydrocarbon type analysis and octane numbers with variation in feed type,process severity(temperature and catalyst/oil ratio),and conversion are also presented and discussed.

Risk Matrix as a Tool for Risk Analysis in Underwater Operations in the Oil and Gas Industry

The study is a cross-sectional design assessment of the likelihood, frequency and severity of hazards associated with underwater operations in the Niger Delta. Five oil and gas companies were used for this study selected by a purposive method given that they had the highest number of workers involved in underwater operations. A sample size of 418 was computed to which the questionnaires were administered with response rate of 95.93%. Data analyses were carried out to cover descriptive statistics, analysis of variance and Pearsonal correlation coefficients. The 4 by 4 risk assessment matrix for the likelihood and consequences showed that 8 out of 20 underwater hazards were categorized as having very high risk according to their risk ratings. The eight hazards categorized based on their risk IDs were H01, H03, H04, H08, H10, H11, H12, and H15. The 4 by 4 risk matrix for frequency and consequences revealed that two hazards (Piracy & bandit attack/kidnapping (H01) and Other main vessels/heavy object dropping or falling load/collision (H08)) were identified to be of very high risk.

Analysing Delay Impact from Potential Risk Factors on Project Delivery of Oil and Gas Pipeline:A Case Study in IRAQ

The aim of this paper is to present the design and specifications of an integrated Delay Analysis Framework(DAF),which could be used to quantify the delay caused by the Risk Factors(RFs)in Oil and Gas Pipelines(OGPs)projects in a simple and systematic way.The main inputs of the DAF are(i)the potential list of RFs in the projects and their impact levels on the projects and the estimated maximum and minimum duration of each task.Monte Carlo Simulation integrated within@Risk simulator was the key process algorithm that used to quantify the impact of delay caused by the associated RFs.The key output of the DAF is the amount of potential delay caused by RFs in the OGP project.The functionalities of the developed DAF were evaluated using a case study of newly developed OGP project,in the south of Iraq.It is found that the case study project might have delayed by 45 days if neglected the consideration of the RFs associated with the project at the construction stage.The paper concludes that identifying the associated RFs and analysing the potential delay in advance will help in reducing the construction delay and improving the effectiveness of the project delivery by taking suitable risk mitigation measures.

Coexistence of natural gas hydrate,free gas and water in the gas hydrate system in the Shenhu Area,South China Sea

Shenhu Area is located in the Baiyun Sag of Pearl River Mouth Basin,which is on the northern continental slope of the South China Sea.Gas hydrates in this area have been intensively investigated,achieving a wide coverage of the three-dimensional seismic survey,a large number of boreholes,and detailed data of the seismic survey,logging,and core analysis.In the beginning of 2020,China has successfully conducted the second offshore production test of gas hydrates in this area.In this paper,studies were made on the structure of the hydrate system for the production test,based on detailed logging data and core analysis of this area.As to the results of nuclear magnetic resonance(NMR)logging and sonic logging of Well GMGS6-SH02 drilled during the GMGS6 Expedition,the hydrate system on which the production well located can be divided into three layers:(1)207.8–253.4 mbsf,45.6 m thick,gas hydrate layer,with gas hydrate saturation of 0–54.5%(31%av.);(2)253.4–278 mbsf,24.6 m thick,mixing layer consisting of gas hydrates,free gas,and water,with gas hydrate saturation of 0–22%(10%av.)and free gas saturation of 0–32%(13%av.);(3)278–297 mbsf,19 m thick,with free gas saturation of less than 7%.Moreover,the pore water freshening identified in the sediment cores,taken from the depth below the theoretically calculated base of methane hydrate stability zone,indicates the occurrence of gas hydrate.All these data reveal that gas hydrates,free gas,and water coexist in the mixing layer from different aspects.

Evaluation and re-understanding of the global natural gas hydrate resources

Natural gas hydrate(NGH)has been widely considered as an alternative to conventional oil and gas resources in the future energy resource supply since Trofimuk’s first resource assessment in 1973.At least 29 global estimates have been published from various studies so far,among which 24 estimates are greater than the total conventional gas resources.If drawn in chronological order,the 29 historical resource estimates show a clear downward trend,reflecting the changes in our perception with respect to its resource potential with increasing our knowledge on the NGH with time.A time series of the 29 estimates was used to establish a statistical model for predict the future trend.The model produces an expected resource value of 41.46×1012 m3 at the year of 2050.The statistical trend projected future gas hydrate resource is only about 10%of total natural gas resource in conventional reservoir,consistent with estimates of global technically recoverable resources(TRR)in gas hydrate from Monte Carlo technique based on volumetric and material balance approaches.Considering the technical challenges and high cost in commercial production and the lack of competitive advantages compared with rapid growing unconventional and renewable resources,only those on the very top of the gas hydrate resource pyramid will be added to future energy supply.It is unlikely that the NGH will be the major energy source in the future.

Oil and Gas Supply and Demand in China and Its Development Strategy

The paper makes a comprehensive prediction of China＇s future demand for oil and gas with two methods, i.e. the prediction method based on the demand for individual oil and gas products and the method for predicting the total demand. According to the demand prediction of, and the historical data on, the oil and gas consumption, we conduct an analysis of the oil and gas consumption trends, which can be described as six different development periods. On the other hand, the paper makes a comprehensive analysis of the domestic oil and gas resources and, on this basis, makes a basic prediction of the domestic output of oil and gas. The supply and demand situation is also analyzed. By using the SWOT analysis method, the paper puts forward the development strategies for China＇s oil and gas industry and gives some related strategic measures.

A sensitivity analysis of factors affecting in geologic CO_(2) storage in the Ordos Basin and its contribution to carbon neutrality

To accelerate the achievement of China’s carbon neutrality goal and to study the factors affecting the geologic CO_(2)storage in the Ordos Basin,China’s National Key R&D Programs propose to select the Chang 6 oil reservoir of the Yanchang Formation in the Ordos Basin as the target reservoir to conduct the geologic carbon capture and storage(CCS)of 100000 t per year.By applying the basic theories of disciplines such as seepage mechanics,multiphase fluid mechanics,and computational fluid mechanics and quantifying the amounts of CO_(2)captured in gas and dissolved forms,this study investigated the effects of seven factors that influence the CO_(2)storage capacity of reservoirs,namely reservoir porosity,horizontal permeability,temperature,formation stress,the ratio of vertical to horizontal permeability,capillary pressure,and residual gas saturation.The results show that the sensitivity of the factors affecting the gas capture capacity of CO_(2)decreases in the order of formation stress,temperature,residual gas saturation,horizontal permeability,and porosity.Meanwhile,the sensitivity of the factors affecting the dissolution capture capacity of CO_(2)decreases in the order of formation stress,residual gas saturation,temperature,horizontal permeability,and porosity.The sensitivity of the influencing factors can serve as the basis for carrying out a reasonable assessment of sites for future CO_(2)storage areas and for optimizing the design of existing CO_(2)storage areas.The sensitivity analysis of the influencing factors will provide basic data and technical support for implementing geologic CO_(2)storage and will assist in improving geologic CO_(2)storage technologies to achieve China’s carbon neutralization goal.

Volatile Components and Antitumor Activity of Ganoderma lucidum Spore Oil and Its Molecular Distillation Components

[Objectives]To compare the effects of molecular distillation on the flavor and antitumor activity of Ganoderma lucidum spore oil.[Methods]G.lucidum spore oil was separated and purified by molecular distillation technology,and the volatile components of different components of molecular distillation were analyzed by gas chromatography-ion mobility spectrometry(GC-IMS)technology.Human liver carcinoma cells(HepG2),human breast cancer cells(MCF-7),and human cervical cancer cells(Hela)were selected as the tumor cell lines to be tested,and the cell viability was detected by the MTT assay.[Results]Molecular distillation effectively reduced small molecular substances produced by oil oxidation in G.lucidum spore oil,such as heptanal,octanal,linalool,hexanal,E-2-octanal,3-ethylpyridine,etc.Among the heavy components,the content of esters was relatively high,mainly including ethyl levulinate,ethyl crotonate,and amyl butyrate.The MTT cytotoxicity test indicated that G.lucidum spore oil and its molecular distillation components had certain inhibitory effects on the growth of three tumor cells,and G.lucidum spore oil crude oil had the most significant antitumor activity.G.lucidum spore oil crude oil,heavy component,and light component had the most significant antitumor activity on HepG2 cells,followed by MCF-7 cells,and the weakest antitumor activity on Hela cells.The quality of G.lucidum spore oil became higher after molecular distillation,and the rancid smell was reduced,and molecular distillation had little effect on the antitumor activity of G.lucidum spores.[Conclusions]Molecular distillation technology can be applied to the refining of G.lucidum spore oil to improve product quality.

A Heuristic Approach to the Diagnosis of Transformer’s Insulating Oil

The transformer plays so important equipment in power system that engineers take more measures on the insulating oil of transformer by diagnosis. The dissolved gas analysis (DGA) is an effective technique for detecting incipient faults in oil-immersed power transformers. So the paper investigates the DGA methods, while employ the ANSI/IEEE C57.104 standards and the Key Gas diagnosis rules as base to develop a fast transformer fault diagnosis method in practice. I designed a report’s form which was so easy to understand that we can have accurate diagnosis what was up in the body of transformer by EXCEL programmed. The user only keys in the measured data of main gases including CO, H2, CH4, C2H2, C2H4, and C2H6 those gases were taken from ASTM D3612’s instruction. Then the diagnosis result was showed in texts and the plotted figures which were two figures to compare diagnosis the test’s figure with the reference figure of the Key Gas diagnosis rules that was taken the analysis of transformer fault from over past in power system. Last but not least, the proposal offers a simple, quick, and an accurate of diagnosis through human-machine interface. While which was been quickly, simply, and accurately proved on October 25th, 2012 Nan Cou E/S #4 ATr’s insulating oil of diagnosis.

Qualitative and Quantitative Assessment of Petroleum Contaminants in Soils under Tropical Weather Conditions

GC-FID methods for the analysis of Petroleum hydrocarbons were developed and optimised. Contamination of soil from the Niger Delta was investigated about 40 days after crude oil spillage from the Shell Petroleum marginal well head. Soil samples and controls were collected at depths of 0 - 15 cm, 15 - 30 cm and 30 - 60 cm. Samples were analysed using gas chromatography fitted with a flame ionisation detector. Penetration and migration of C10-C26 and C26-C34 hydrocarbons through the soil layers were assessed by cluster analysis to determine the spatial distribution, penetration and similarity of these compounds over the contaminated area. The results also indicated elevated levels of total hydrocarbon contents when compared with the reference sites. Recommendations are made to carefully monitor and remediate the environment.

Modifying Plant Oils for Use as Fuel in Rural Contexts Tanzania: Techno-Economic Analysis

Techno-economic analysis of a small-scale Modified Plant Oil (MPO) production plant that has an annual production capacity of 15,072,741 kg of MPO (batch process) was carried out to estimate the capital and operating costs of a plant. The analysis was done by using a computer model that was designed and simulated with an aid of SuperPro Designer (Version 4.32) software. The specified feedstock was crude Jatropha oil (JO) and the main product was MPO. The major processes involved were degumming, neutralisation and blending. Degumming involved the removal of gums or phospholipids, and two methods were used: water degumming and acid degumming, whereas blending involved mixing of degummed or purified JO with natural gas condensate (NGC) modifier to lower the viscosity of JO. From techno-economic analysis of the process, it was found that the total capital investment of a plant was about US $ 10,222,000 and the predicted unit production cost of MPO was US $ 1.315/kg at a value of US $ 1.0/kg of JO. The economic feasibility of MPO production was found to be highly influenced by the price of feedstock, which contributed about 95% of the total annual production cost. The relationship between plant throughput and unit cost of producing MPO showed that unit production cost was very sensitive to production rate at low annual throughputs. The MPO cost showed a direct linear relationship with the cost of JO, with a change of US $ 0.50/kg of MPO in MPO cost in every change of US $ 0.50/kg of JO in JO price. The process technology simulated was found to be economically viable and can be implemented in rural setting, taking into consideration Tanzania’s rural situation.

Nanopore structure comparison between shale oil and shale gas:examples from the Bakken and Longmaxi Formations

In order to analyze and compare the differences in pore structures between shale gas and shale oil formations, a few samples from the Longmaxi and Bakken Formations were collected and studied using X-ray diffraction, LECO TOC measurement, gas adsorption and field-emission scanning electron microscope. The results show that samples from the Bakken Formation have a higher TOC than those from the Longmaxi Formation. The Longmaxi Formation has higher micropore volume and larger micropore surface area and exhibited a smaller average distribution of microsize pores compared to the Bakken Formation. Both formations have similar meso-macropore volume. The Longmaxi Formation has a much larger meso-macropore surface area, which is corresponding to a smaller average meso-macropore size. CO_2 adsorption data processing shows that the pore size of the majority of the micropores in the samples from the Longmaxi Formation is less than 1 nm, while the pore size of the most of the micropores in the samples from the Bakken Formation is larger than 1 nm. Both formations have the same number of pore clusters in the 2–20 nm range, but the Bakken Formation has two additional pore size groups with mean pore size diameters larger than 20 nm. Multifractal analysis of pore size distribution curves that was derived from gas adsorption indicates that the samples from the Longmaxi Formation have more significant micropore heterogeneity and less meso-macropore heterogeneity. Abundant micropores as well as mesomacropores exist in the organic matter in the Longmaxi Formation, while the organic matter of the Bakken Formation hosts mainly micropores.

Sustainable development of unconventional resources: Analysis of the transient linear flow oriented straight-line analysis technique

On the backdrop of dwindling conventional reserves,unconventional reservoirs have emerged as a pivotal chapter in resource extraction.Despite their challenges,such as low permeability,complex fluid storage,and flow mechanisms,hydraulic fracturing technology has underpinned the development of unconventional reservoirs.Consequently,this has brought about a shift in the sequence of flow regimes,e.g.,the transient radial flow regime has been largely shortened by the lengthy transient linear flow regime due to the low permeability of unconventional reservoirs.Moreover,straight-line analysis(SLA),the simplest technique in rate transient analysis(RTA),is a fundamental and potent tool for swiftly extracting reservoir and hydraulic fracture information,estimating oil and gas reserves,and furnishing crucial initial data for subsequent historical matching processes.However,there is currently a dearth of review papers pertaining to a necessary guide of applying SLA in various transient linear flow(TLF)regimes and different unconventional reservoirs.Hence,this paper commences by elucidating the classification of TLF regimes,commonly used methods for recognizing flow regimes,and the diverse SLA methods used for different TLF regimes.Subsequently,it delves into a discussion of different modification techniques for variable rate/flowing pressure,gas phase,complex reservoir characteristics in unconventional reservoirs,and dynamic drainage area concepts etc.Furthermore,the application of SLA in specific domains,namely core analysis and the flowback period,is described.It culminates by surveying the advancements through an integration of novel technologies to enhance estimation accuracy.The paper also highlights certain drawbacks of current SLA technology and proposes new research directions.Ultimately,this paper would serve as an indispensable resource,offering foundational knowledge for the application of SLA in TLF to promote the production of global unconventional resources in a cost-effective and environmentally sustainable fashion in the face of a climate-resilient world.

Support Vector Machine-Based Fault Diagnosis of Power Transformer Using k Nearest-Neighbor Imputed DGA Dataset

Missing values are prevalent in real-world datasets and they may reduce predictive performance of a learning algorithm. Dissolved Gas Analysis (DGA), one of the most deployable methods for detecting and predicting incipient faults in power transformers is one of the casualties. Thus, this paper proposes filling-in the missing values found in a DGA dataset using the k-nearest neighbor imputation method with two different distance metrics: Euclidean and Cityblock. Thereafter, using these imputed datasets as inputs, this study applies Support Vector Machine (SVM) to built models which are used to classify transformer faults. Experimental results are provided to show the effectiveness of the proposed approach.

Improvement on Condition Assessment Model for Oil-paper Insulation

Identification of the aging condition and the failure probability of oil-paper insulation in transformer is important for improving the reliability of electric power transmission system and applying life cycle cost (LCC) management to electrical equipment. Based on data obtained in a series of multi-accelerated-aging experiments, two approaches for calculating failure probability of oil-paper insulation were compared in aspects of degree of polymerization (DP) and condition ranking. In the experiments, mineral oil and cellulose paper are sub- jected to electrical and thermal stresses, and several parameters, including dissolved gases’ volume fraction, furfural content, moisture content, and degree of polymerization, are measured after the aging process. Results show that weight of carbon oxide, which has a close relationship with cellulose paper degradation, is much higher in DP model than in condition ranking model. Moreover, it is concluded that DP model is more practically accurate than condition ranking model, because aging of cellulose paper rather than mineral oil is the key and critical factor of oil-paper insulation aging.