Crude Oil Production Research Articles

Production of crude oil from industrial wastes and wastewaters by hydrothermal liquefaction

Hydrothermal Liquefaction (HTL) is a promising thermochemical treatment suitable for the valorization of a wide variety of organic wastes and wastewaters. Many research studies have demonstrated the suitability of HTL to produce bio-oil from biomass wastes, but few works have focused on the application of HTL to industrial wastes and wastewaters. The objective and novelty of this work are the study of HTL suitability over a specific selection of industrial residues that present notable drawbacks when treated by conventional waste management methods, including technical problems or high costs. Most of the wastes presented poor results from the technical or energetical point of view. However, liquid surfactant wastewaters were successfully treated by HTL at 300ºC and 100 bar in a 300 mL stirred batch reactor, producing a crude oil yield of around 16%, with a High Heating Value (HHV) of up to 30 MJ/kg. The composition and quality of the crude oils obtained have also been determined and compared against conventional biomass fuels.Graphical abstract

Entropy analysis of Cu-Al2O3 based hybrid and Cu based mono nanofluid flows through porous medium: A comparative study

The motive of this research article, is to present a comparative study of entropy generation for a system of MHD mixed convection non-Darcy porous medium flow of mono and hybrid nanofluids over a melting surface. Darcy–Forchheimer model for the flow through porous medium is employed to formulate the problem under consideration. The dimensional momentum and heat equations governing the flow are transformed into a non-dimensional ODEs with the help of similarity variables. The similarity solution of the dimensionless differential equation is computed with the MATLAB’s bvp4c package. The influence of various embedded parameters on the flow fields and entropy generation are examined. The study reveals that the entropy generation in Cu−Al2O3 water based hybrid nanofluid is smaller compared to that of Cu-water based mono nanofluid. The findings of the study have bearing in the fields involving oil flow filtration, crude oil production, electronic cooling equipment etc.

Impact of fracturing fluid retention and flowback on development effect after large scale fracturing in shale oil wells: A case study from the shale oil of Chang 7 Member, Yanchang Formation, Ordos Basin

In order to reveal the impact of fracturing fluid retention and flowback on the development effect after large-scale fracturing in shale oil wells, and to formulate a reasonable flowback policy, this paper employs a combination of core physical simulation experiments and theoretical analysis. We have designed a specially designed device that can evaluate the development effect of quasi-natural energy in oil reservoirs. The impact of fracturing fluid retention on development is simulated by changing the amount of fracturing fluid injected into the formation in a fractured horizontal well model (referred as injection volume), and the impact on development effect is analyzed by changing the properties of fracturing fluid to adjust the difference in the degree of flowback. Based on the experimental results, the mechanism of fracturing fluid retention and flowback after large-scale fracturing in shale reservoirs is further explored. The results of the experiments show that the flowback rate of fracturing fluid exhibits a monotonic decreasing trend with increasing the volume of injected fluid, as increasing the volume of injected fluid helps to enhance its retention in the formation and reduce the flowback rate. The degree of fracturing fluid flowback is critical to the mobility of crude oil in the tight reservoir. The entering of fracturing fluid into the reservoir slows down the rate of discharge in the fracture network, effectively extending the reach of the fracturing fluid in the tight reservoir and allowing more crude oil to be used, which in turn results in higher crude oil production. However, too much injection fluid may affect the fluid production. Simulation experiments reveal that the use of fracturing fluid retention or controlling the rate of flowback by changing the viscosity of fracturing fluid can be a way to enhance the development effect of horizontal shale oil wells. The results of this paper provide a basis for understanding the mechanism of shale oil development, exploring technical ideas to improve the development effect, and making decisions on the flowback parameters.

Crude oil security in a turbulent world: China's geopolitical dilemmas and opportunities

China's economic and social development relies heavily on crude oil, which it imports and consumes more than any other country. Thus, the country's oil security is crucial. Geopolitical risk (GPR) is used to describe the instability and uncertainty resulting from political conflicts, terrorism, wars, sanctions, and other events that affect the production, transportation, and consumption of crude oil. Therefore, we use MF-VAR to examine how geopolitical risk GPR causes changes in Chinese crude oil security (COS). Unlike previous studies, we treat GPR as an outcome variable and use oil demand and cost channels to analyse its effects on COS. Quarterly government hazards endanger Chinese oil safety, and combined frequency data fixation reveals a dynamic link in various quarters of the year. Hence, to ensure a consistent supply of crude oil, the Chinese government's oil corporations must implement several initiatives, including purchasing shares and developing oil fields. To protect oil production and transportation, China should also forge strong links with nations that export oil and participate in UN initiatives such as the Somali escort and peacekeeping in Africa. To better manage oil price volatility brought on by geopolitical dilemmas, RMB-based crude oil futures are a smart approach for increasing affordability.

Prediction on Filtration Period of Granular Bed Filter Used in Purifying Produced Water in Oil Field

Summary The granular bed filter can purify the water produced in the crude oil production process by adsorbing oil droplets and suspended solids. A regeneration operation is needed to clean the granular media and recover filtration capacity after a certain operation duration. Currently, filtration models are mainly used for one type of particle removal, with few applications in the filtration system of produced water containing oil droplets and suspended solids. However, the different deposition morphologies of oil droplets and suspended solids in the filter bed can affect the prediction of the filtration process. In this work, we develop a transient filtration model based on the multiphase system transport equations coupled with the filtration rate and momentum exchange equations to predict simultaneously the effluent concentration and the pressure drop buildup, which considers the effect of deposition morphologies of oil droplets and suspended solids on filtration behaviors. The model hypothesizes that particle removal occurs through deep bed filtration mechanisms, and initial filtration coefficients are predicted by trajectory analysis without relying on experimental data. After that, we propose a method for predicting the filtration period, and analyze the effect of particle size and water temperature on the filtration process. Results show that the filtration process can be divided into two major stages—the main filtration zone migration, followed by the saturation front migration. With an S-shape increase in the effluent concentration, the pressure drop of the filter bed increases in a parabolic shape. When the diameter median of suspended solids is 5 μm, and the water temperature is 20°C, the filtration period was determined to be 24 hours to meet both water quality and maximum usable pressure drop of 20 kPa. With the increase in non-Brownian suspended solid size, the interception and gravitational forces increase the removal efficiency of suspended solids, which results in a slight decrease in the removal efficiency of oil droplets and an increase in the pressure drop of the filter bed. As the water temperature increases, the viscosity of the produced water decreases, and the oil droplets and suspended solids are more easily removed, but the pressure drop of the filter bed increases. In this work, we provide new ideas and methods to properly design, operate, and manage filters in a sustainable and energy-efficient way.

Evaluation of Polymers as a Strategy to Reduce Asphaltene Adsorption on Rock Surface

Summary One of the most extensively studied flow assurance issues in the petroleum industry is the precipitation and deposition of asphaltenes. This is in part because of the molecular structure’s intricacy and the interconnected factors that influence and regulate its activity. The injection of inhibitors and dispersants, which affects the economics of crude oil production, is now the most successful strategy for preventing asphaltene problems. Throughout the crude oil supply chain, from the reservoir through the tubing and refinery systems, asphaltene is a concern. However, the area closest to the wellbore, where the highest pressure drop is seen, is the most prone to asphaltene adsorption and deposition. Thus, the goal of this study is to investigate the use of sacrificial fluids to reduce asphaltene adsorption and deposition around the wellbore. To prevent asphaltene from interacting with the rock surface and shifting the asphaltene problem into tubing, where its impact on wettability is low, polymers with functional capabilities are investigated. The performance test (adsorption inhibition capacity), binding energy analysis, adsorption experiments (adsorption affinity, configuration, and mechanism), and fluid characterization (salinity tolerance, surface energy, and interfacial tension) of the selected novel fluids for asphaltene adsorption mitigation are presented. The investigation of ion-specific rock-fluid interactions offers great potential in the search for an effective answer to the asphaltene problem, according to the results. This was proved by the fluid levels of binding energy to carbonate rock samples and their capacity to prevent interactions between asphaltene molecules and the rock surface. These findings provide a fresh perspective on the creation of an economic strategy to deal with asphaltene issues and their effects. This study is the first to investigate a long-term fix for wettability changes caused by asphaltene adsorption on rock minerals. The findings revealed that an optimal concentration exists for the polymers under study, at which the asphaltene interaction is mitigated. More so, surface energy evaluation is observed to be a critical tool that can help to screen polymers for this application. Furthermore, the method of implementation, which could be either squeeze operation or continuous injection, is critical to the success of the remediation.

Methodology for examining the relationship between oil rent and crude oil production: Evidence from Cameroon

The relationship between oil rent and crude oil production remains unexplored in Cameroon. This study therefore aims to apply the Autoregressive Distributed Lag (ARDL) estimation technique and the Granger causality test using the Toda–Yamamoto procedure to capture the symmetric impact and causality links between oil rent and crude oil production in Cameroon. The study covers the period from 1977 to 2019, and includes crude oil prices, human development index (HDI) and corruption as other variables. The study indicates that there is a significant negative linear impact of crude oil production on oil rent and a bidirectional causality between oil rent and crude oil production. Finally, the price of crude oil, HDI and corruption are found to pass through production to influence oil rent. The results of this study will guide policy makers in managing and sustaining oil revenues for growth and prosperity.•The paper examines the linear impact of crude oil production on oil rent and the causal links between crude oil production and oil rent by incorporating crude oil prices, HDI and corruption.•Bidirectional causality between oil rent and crude oil production.•Convergence of crude oil price, HDI and corruption to crude oil production to influence oil rent.

Uyo, Akwa Ibom State and the Challenges of Tourism Development: the case of Inappropriate Urban Development Drives

Geographically, AkwaIbom State is divided into the coastal mangroves of Africa Central and transition areas at the southernmost point. The Imo and Cross Rivers, flow along the eastern and western borders respectively, while Kwa Ibo River crosses the state before flowing into the Bonny River. Economically, the state is the hub of crude oil and natural gas production in the country; with Ibeno, Mbo and Eastern Obolo as oil-producing local government area’s key minor industries involve agriculture as the state has substantial cocoyam, yam, and plantain crops along with fishing and agriculture. Yet, the state has no substantive or reasonable convention centre. Convention centre is one of the key segments of the events industry, along with hotels, and unique shows. They are designed to host any type of event, including conferences, conventions, and exhibitions. They are mostly located in or near the urban centres or other major population centres and are designed to meet the unique needs of the gathering groups, organizers, visitors, and exhibitors. In the past, the government approaches to urban development programmes are regrettable, retrogressive and benign. As a result, adequate measures and proper administrative management of the government laws and policies are recommended for tourism development in Uyo. Hiring of poorly trained and unqualified personals should be minimized and properly and adequately trained professionals in different areas of interest hired to man and manage the facilities of the state for upwards growth. The urban players in the state should pay more and better attention to the state’s tourism development hence, a sustainable convention centre.

Research on Fault Diagnosis System of IOT for Oil Well Pump Based on Machine Learning

Abstract In order to realize automatic prediction and processing of remote fault diagnosis of oil well pumps distributed in different regions by crude oil production enterprises, a fault diagnosis system for oil well pumps based on machine learning was researched and designed. This fault diagnosis system is composed of three layers (perception layer, network layer and control application layer) Internet of Things structure. The function and characteristics of each layer are analyzed in this paper, and the hardware composition and control principle of sensor nodes and aggregation nodes of the measurement and control system are discussed and gives the node microcontroller program design flow chart and the main module content of the IoT central computer software design. This paper focuses on the principle of machine learning for fault diagnosis and prediction, and deeply explains the algorithm steps of using LSTM for fault diagnosis of oil well pumps. The enterprise application experiment results show that, compared with the traditional manual well patrol fault diagnosis method, this system has the advantages of convenient operation and maintenance, low labor intensity, high timeliness and accuracy of fault diagnosis, which can better reduce equipment maintenance costs for enterprises.

Crude Oil Production, Corruption and Upstream Oil Revenue in Nigeria: General Outlook, Conditions and Methodology

The study examined general outlook and conditions of crude oil production, corruption risk and upstream oil revenue in Nigeria. The study focused mainly on the revenue generated from crude oil production and oil export with the purpose of assessing oil exploration and corruption with the objective of investigating Nigeria’s oil export and its contribution to the growth of revenue generation and finding out if the level of corruption affects the upstream revenue generation in Nigeria. it is discovered that the following variables are germane in the empirical studies reviewed and econometric models are conceptualized that proven oil reserve, OPEC quotas, global oil demand, global oil supply, geopolitical risk index, disaster risk index, global terrorism index, global oil price, exchange rate variation, upstream oil theft, number of pipeline vandalism, oil bunkering, tax evasion and corruption perceptions index are relevant and possible determinants of downstream oil revenue in Nigeria. An empirical study to investigate the relationship and causal effect of the above-mentioned factors are recommended for further study with a view to making reliable policy statements on revenue sustainability and highlighting and reducing the counterproductive effects of corruption risks in the exploration and production of crude oil in Nigeria.

Dissipative Particle Dynamics-Based Simulation of the Effect of Asphaltene Structure on Oil-Water Interface Properties.

Asphaltenes are the main substances that stabilize emulsions during the production, processing, and transport of crude oil. The purpose of this research is to investigate the process of asphaltenes forming interfacial films at the oil-water interface by means of dissipative particle dynamics (DPD) and the effect of asphaltenes of different structures on the oil-water interface during the formation of interfacial film. It is demonstrated that the thickness of the interfacial film formed at the oil-water interface gradually increases as the asphaltene concentration rises and the amount of asphaltene adsorbed at the oil-water interface gradually multiplies. Both the number and type of heteroatoms in asphaltenes affect the interfacial behavior of asphaltenes. The interface activity of asphaltenes can be enhanced by increasing the number of heteroatoms in the asphaltene, and the type of heteroatom affects as well the interfacial activity of the asphaltene as it affects the aggregation behavior of the asphaltene in the system. As the number of asphaltene aromatic rings increases, the oil-water interfacial tension (IFT) trends down gradually, while the effect of alkyl side chains on the reduction of IFT of asphaltenes is different, and asphaltenes with medium length alkyl side chains can reduce IFT more efficiently.

Unveiling ZrO2/natural zeolite catalytic performance on hydrocracking palm oil mill effluent residue

Palm oil mill effluent (POME) is the largest liquid waste from crude palm oil production. This liquid waste still contains a lot of chemical components, solid deposits, and oil which is dangerous if released directly into the environment. The residual oil and grease components contained in POME can be further extracted and converted into fuel fractions. This study investigates the conversion of residual oil from POME into fuel fractions through hydrocracking. A ZrO2/Sarulla natural zeolite (SNZ) catalyst was used, characterized by a particle size of 1-1.5 µm, a surface area of 73.3 m2/g, a pore volume of 0.161 cc/g, and a pore diameter of 3.35 nm. The effect of catalyst mass was studied, with the total conversion increasing to a certain extent with increasing catalyst mass, however, an increase in coke formation decreased the product yield. The highest gasoline fraction selectivity was obtained with a catalyst mass of 0.09 wt% (~42%), while the kerosene fraction was most obtained with a catalyst mass of 0.15 wt% (~40%). The liquid product with a catalyst mass of 0.15 wt% had the highest HHV of 44.2 MJ/kg, a 12% increase from the HHV of POME oil residue (39.4 MJ/kg). The results demonstrate the potential of using residual oil from POME as a source for fuel production and the use of natural zeolite-based catalysts as hydrocracking catalysts.

Effect of Crude Oil Pollution on Artisanal Fishing in Asari- Toru, Akuku-Toru and Degema Local Government Areas of Rivers State, Nigeria

This study analyzed the effect of crude oil production on artisanal fishing in selected local government areas of Rivers State. Purposive and random sampling technique were used in selecting respondents for the study. The sample size for the study was made up of 90 artisanal fishing folks. Data were elicited from fishing folks with a structured questionnaire which were administered to the respondents. Percentage, mean, costs and returns and multiple regression were used for the analyses of data. The result showed that the mean age of respondents was 40 years, while the mean house hold size was 6 persons. The result also showed that majority of the respondents had primary education and that most respondents had no access to credit facilities to enable them purchase fishing equipment for their operations. Also, majority (66.7%) were members of cooperative society while majority (71%) reported incidence of oil spillage in the study area. The regression analysis also revealed that the output of individual fishing households is significantly influenced by variables, namely, capital, labour, operating costs, fishing experience and oil spill. There is the need for policies that could compel oil companies to minimize oil spill in the farmers’ fishing environment.

A rapidly switchable CO2-responsive Pickering emulsions based on supramolecular amphiphilic surfactants and nano-SiO2

A novel rapidly switchable CO2/N2-responsive Pickering emulsifier based on supramolecular amphiphilic surfactants (SDOA) and nano-SiO2 has been fabricated. SDOA was constructed by mixing Jeffamine D-230 and oleic acid (HOA) at 1:1 stoichiometric ratio. Compared with conventional small-molecule emulsifiers, the novel rapidly switchable CO2/N2-responsive Pickering emulsifier was prepared with inexpensive raw materials by a simple method, and there was no contaminant generation during synthesis. A new CO2/N2-responsive Pickering emulsion was prepared on this basis, and its stable performance and responsiveness were investigated in depth. The results show that this emulsion can be stable for a long time (more than 30 days) at a low surfactant dosage (0.5 mmol/L) through in situ hydrophobization of SiO2 nanoparticles by hydrogen bonding and electrostatic adsorption. In addition, the emulsion broke rapidly and completely after 10 s of CO2 introduction into the stable emulsion, and the emulsion could be reconstructed in response to N2 purging for 5 min at 60 ℃ followed by homogenization. The switching behavior of the emulsion is due to decomposition of the pseudo amphiphile by bubbling CO2 into the system and both the protonated D-230 ions and the neutral HOA produced have no in situ hydrophobization to SiO2 particles. At 60 ℃, the influx of N2 will drive out CO2, making HOA re-transform into hydroxide ion, and after re-combining with D-230 ion, it can again perform in-situ hydrophobization on SiO2 particles, thus forming a stable emulsion. Thanks to the ability of SiO2 nanoparticles and D-230 ions to maintain electrostatic adsorption after the passage of CO2, compared with previous studies, the emulsion can be completely demulsified at a higher pH value (about 5.5), fewer bicarcarbonate roots are formed, less CO2 needs to be introduced, and N2 required to re-stabilize the emulsion is also reduced. This greatly increases the response efficiency of the emulsion and reduces the energy loss and the cost of putting the emulsion system into practical application. This research has important implications for fossil fuel generation, production and transportation of crude oil, and other areas.

Effect of molecular environment on asphaltene aggregation: a molecular dynamics study

Asphaltene deposition poses a significant threat to the safe production of crude oil as it tends to occur in forming porous media, wellbores, pipelines, and refining equipment. It is also responsible for the high viscosity of crude oil, making it challenging to recover heavy crude oil. This study investigates the impact of aliphatic chain length on asphaltene aggregation and the molecular properties of organic solvents and dispersants interacting with asphaltenes. To achieve this, two model asphaltenes, M1 and C5Pe, were used in molecular dynamics simulations using radial distribution function, root means square displacement, diffusion coefficient, solubility parameter, cohesion energy density, and interaction energy as characterization parameters. The simulations revealed that the aggregation onset of C5Pe and M1 occurs at 2–5 Å at room temperature and pressure, and π–π stacking is the primary mode of aggregation, with the presence of heteroatomic groups providing additional forces for stable aggregation. Additionally, it was found that the π–π interactions weakened with the increase of the side chain length. The study also investigated the molecular behavior of asphaltenes in six organic solvents and found that M1 was more soluble in aromatic solvents than C5Pe, and undesirable solvents could induce asphaltene aggregation. Furthermore, the effect of five dispersants on asphaltene aggregation was explored, with PIBSI, BEHP, B-DBSA, CTAB, and benzoic acid showing decreasing dispersing ability in that order at lower concentrations. However, at higher concentrations, the effect of some dispersants diminishes and triggers self-aggregation behavior.

Co-culture of Acinetobacter sp. and Scedosporium sp. immobilized beads for optimized biosurfactant production and degradation of crude oil

The widespread exploration and exploitation of crude oil has increased the prevalence of petroleum hydrocarbon pollution in the marine and coastal environment. Bioremediation of petroleum hydrocarbons using cell immobilization techniques is gaining increasing attention. In this study, the crude oil degradation performance of bacterial and fungal co-culture was optimized by entrapping both cells in sodium-alginate and polyvinyl alcohol composite beads. Results indicate that fungal cells remained active after entrapment and throughout the experiment, while bacterial cells were non-viable at the end of the experimental period in treatments with the bacterial-fungal ratio of 1:2. A remarkable decrease in surface tension from 72 mN/m to 36.51 mN/m was achieved in treatments with the bacterial-fungal ratio of 3:1. This resulted in a significant (P < 0.05) total petroleum hydrocarbon (TPH) removal rate of 89.4%, and the highest degradation of n-alkanes fractions (from 2129.01 mg/L to 118.53 mg/L), compared to the other treatments. Whereas PAHs removal was highest in treatments with the most fungal abundance (from 980.96 μg/L to 177.3 μg/L). Furthermore, enzymes analysis test revealed that catalase had the most effect on microbial degradation of the target substrate, while protease had no significant impact on the degradation process. High expression of almA and PAH-RHDa genes was achieved in the co-culture treatments, which correlated significantly (P < 0.05) with n-alkanes and PAHs removal, respectively. These results indicate that the application of immobilized bacterial and fungal cells in defined co-culture systems is an effective strategy for enhanced biodegradation of petroleum hydrocarbons in aqueous systems.

Optimization of acid ensilaging method for the extraction of oil from Lake Victoria nile perch’ lates niloticus viscera

A study was carried out to optimize the wet acidic rendering for extracting oil from Nile perch viscera. Oil was extracted at 93oC by varying the acid concentration from 0 – 10% and heating time from 5 – 25 minutes. The oil yield, lipolytic, oxidative and color qualities were determined to compare the effect of acid and time using a factorial completely randomized design. Statistical analysis of data was carried out at p  0.05 using GenStat 13th edition software. There was significant difference in yield, with interaction between acid concentration and heating time, the yield being highest at 15 minutes and declining thereafter with increasing acid concentration. There was significant difference in free fatty acids (%FFA), with interaction between acid concentration and heating time, values increasing with acid concentration and heating time. Heating times of 5 and 15 minutes produced the lowest %FFA at 0% acid concentration, being significantly higher after 15 minutes. All the %FFA values were within permitted limits for crude fish oil, however. There was difference in peroxide value (PV) with interaction between acid concentration and heating time, decreasing with increasing concentrations. Heating for 15 and 25 minutes produced lower PV for 0% acid concentration, with no difference between them. But the PVs were within permitted limits for crude fish oil. There were differences in color intensity, with acid concentrations, heating time not producing a significant difference, and the interaction between acid concentration and heating time not significant. There was significant difference in color intensity between 0% and subsequent acid concentrations, increasing with acid concentration. Heating for 15 minutes without acid is therefore the most suitable combination for mass production of crude oil from Nile perch viscera.

Enhancing deoxygenation of waste cooking palm oil over CaO-MgO catalyst modified by K2O for green bio-fuel

There are challenges to replacing traditional fossil fuels completely, so producing efficient green biofuels is crucial. In this work, waste cooking palm oil (WCPO) was used as raw material to produce biofuel through pyrolytic catalysis cracking (PCC) over alkaline catalysts as CaO-MgO with various dopants at 0, 3, 6 and 9 wt% K2O contents. The WCPO reacted under atmospheric pressure without purging gases at 500, 525 and 550 °C, respectively. Catalysts were characterized by various techniques in terms of physical and chemical properties. The pyrolytic oil (PO) was separated from the crude oil product. Then, PO was characterized by TGA/DTG, CHNO, FTIR and GC–MS. The PO was distilled following an ASTM D86 method. The properties of biofuels, such as density, kinematic viscosity and acidity, were measured. The basicity of the catalyst increased with increasing K2O contents. K2O not only enhanced the pyrolytic-liquid product yield but also significantly reduced the oxygenated compounds in biofuel through the deoxygenation process to improve biofuel quality. The different reaction temperatures were observed in which low-temperature reaction provided incompletely cracking heavy molecules, and more gas product occurred at the high reaction temperature. Surprisingly, the fatty acid compounds of WCPO were transferred to hydrocarbon compounds by deoxygenation reactions confirmed by GC–MS and FTIR results. The highest pyrolytic oil yield was approximately 92 vol% compared with crude oil product, obtained from 3 wt% K2O-MgO/CaO and 525 °C. The paraffinic and olefinic compounds were the main hydrocarbon products with K2O doping catalysts, while ketone compounds were found in all catalysts via the ketonic decarboxylation mechanism. In this condition, pyrolytic oil was completely distilled to get gasoline, kerosene and diesel. The kinematic viscosity and density were under ASTM standards except for acidity. Remarkably, the acidity of biofuel with K2O doping was reduced about 2–3 times compared to MgO/CaO alone.

An online physical simulation method for enhanced oil recovery by air injection in shale oil

In order to understand the mechanism of air flooding shale oil, an online physical simulation method for enhanced shale oil recovery by air injection was established by integrating CT scanning and nuclear magnetic resonance (NMR). The development effect of shale oil by air flooding under different depletion pressures, the micro-production characteristics of pore throats with different sizes and the mechanism of shale oil recovery by air flooding were analyzed. The effects of air oxygen content, permeability, gas injection pressure, and fractures on the air flooding effect in shale and crude oil production in pores with different sizes were analyzed. The recovery of shale oil can be greatly improved by injecting air into the depleted shale reservoir, but the oil displacement efficiency and the production degree of different levels of pore throats vary with the injection timing. The higher the air oxygen content and the stronger the low-temperature oxidation, the higher the production degree of pores with different sizes and the higher the shale oil recovery. The higher the permeability and the better the pore throat connectivity, the stronger the fluid flow capacity and the higher the shale oil recovery. As the injection pressure increases, the lower limit of the production degree of pore throats decreases, but gas channeling may occur to cause a premature breakthrough; as a result, the recovery increases and then decreases. Fractures can effectively increase the contact area between gas and crude oil, and increase the air sweep coefficient and matrix oil drainage area by supplying oil to fractures through the matrix, which means that a proper fracturing before air injection can help to improve the oil displacement effect under a reasonable production pressure difference.

An intelligent diagnosis method for oil-well pump leakage fault in oilfield production Internet of Things system based on convolutional attention residual learning

In the Internet of Things (IoT) system for oil field production, oil-well pump leakage is one of the most challenging faults to detect. Once the pump leakage fault occurs, it will severely impact crude oil production. Therefore, accurate diagnosis of oil-well pump leakage faults is highly necessary. However, achieving accurate diagnosis through existing artificial intelligence methods remains a challenge due to the prolonged and progressive nature of oil-well pump leakage faults. This paper proposes a novel methodology for diagnosing oil-well pump leakage. Specifically, we propose a time-series data transformation method that ingeniously transforms difficult-to-identify pump leakage long time-series data variation features into image pixel-level texture features, and based on the characteristics of differences in image texture features under different states, we propose the structure of convolutional residual blocks with attributes and spatial attention for oil-well pump leakage fault diagnosis, which enables more accurate fault diagnosis by assigning more attention weights to extract valuable fault information. Through extensive experimentation, we found that the diagnosis process proposed in this paper outperforms sequence models such as LSTM and GRU, achieving a diagnostic accuracy of 98.36% for oil-well pump leakage faults. Moreover, it leads to a significant improvement of 19.40% and 10.36% in accuracy compared to conventional CNN and ResNet models, respectively. Therefore, in the actual production of oilfields, this method can effectively meet the detection requirements for oil-well pump leakage.