Petroleum Recovery Research Articles

L-tryptophanium picrate as novel anticorrosion agent for mild steel in 5% HCl: A detailed experimental and in silico investigation

Acidizing in petroleum recovery often leads to severe corrosion of mild steel, necessitating the development of highly effective corrosion inhibitors. In this study, L-tryptophanium picrate ( [Trp][Pic]), an amino acid derivative synthesised by one-step synthesis involving two-component acid–base reaction between L-tryptophan and picric acid, is investigated as a novel corrosion inhibitor for mild steel in 5% HCl. A comprehensive experimental and theoretical approach was employed to evaluate its performance. Weight loss measurements, potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS) were used to determine the inhibition efficiency. At 30°C, [Trp][Pic] significantly increased the polarization resistance from 81.08 Ω cm² in the uninhibited solution to 462.15 Ω cm² in the presence of 100 ppm of [Trp][Pic], achieving an inhibition efficiency of 82.46%. PDP results confirmed its mixed-type behavior, reducing both anodic and cathodic reactions. Surface analysis through SEM and AFM demonstrated the formation of a uniform protective film of [Trp][Pic] that shielded the steel surface. X-ray photoelectron spectroscopy (XPS) supported the role of donor-acceptor interactions between heteroatoms and Fe atoms in the chemisorption mechanism. Molecular dynamics (MD) simulations identified key binding sites responsible for the strong adsorption of [Trp][Pic], providing insight into the molecular-level mechanism of inhibition. These findings highlight the potential of [Trp][Pic] as a promising corrosion inhibitor for industrial applications.

An improved convolutional architecture for quantitative characterization of pore networks in fine-grained rocks using FIB-SEM

Focused ion beam scanning electron microscope (FIB-SEM) is one of the most advanced imaging techniques for analyzing and understanding complex pore networks in shale and other fine-grained formations. However, FIB-SEM imaging tends to be time-consuming and labor-intensive and can result in biased interpretations associated with pore analysis. Recently, U-Net or its variants for image segmentation have been applied to capture microscopic pores at higher resolutions. The ‘traditional’ encoder-decoder-based approaches tend to detect very fine-scale microscopic pores poorly. This study presents an improved convolutional architecture for automatically analyzing pore structures in shale reservoirs using FIB-SEM. It does so by applying an overcomplete convolutional architecture, KiU-Net, to capture very fine-scale microscopic pores by accurately defining their edges in the input FIB-SEM images. The KiU-Net learns low and high-level features by making the model more sensitive to fine-scale microscopic pores in the input images. The purpose of this study is to demonstrate KiU-Net's capabilities by analyzing different shale formations with varying characteristics. The results indicate that KiU-Net is more accurate and efficient than other methods in predicting nanopores in the Longmaxi, Niutitang, Qingshankou, Qianjiang, and Yanchang Formations (China), Bakken shale (Canada), and coal reservoirs (China). Furthermore, KiU-Net demonstrated the advantage of requiring fewer parameters and achieving super convergence compared to the Attention U-Net technique. KiU-Net addresses the challenges of the Edge-Threshold Automatic Processing (ETAP) methods by capturing very fine-scale microscopic pores with accurate edges. This study further enhances the accuracy and efficiency of pore analysis in shales, thereby offering an improved method for understanding shale reservoir quality with the potential to improve petroleum recovery from such formations.

Enhanced low-cost lipopeptide biosurfactant production by Bacillus velezensis from residual glycerin.

Biosurfactants (BSFs) are molecules produced by microorganisms from various carbon sources, with applications in bioremediation and petroleum recovery. However, the production cost limits large-scale applications. This study optimized BSFs production by Bacillus velezensis (strain MO13) using residual glycerin as a substrate. The spherical quadratic central composite design (CCD) model was used to standardize carbon source concentration (30g/L), temperature (34°C), pH (7.2), stirring (239rpm), and aeration (0.775vvm) in a 5-L bioreactor. Maximum BSFs production reached 1527.6mg/L of surfactins and 176.88mg/L of iturins, a threefold increase through optimization. Microbial development, substrate consumption, concentration of BSFs, and surface tension were also evaluated on the bioprocess dynamics. Mass spectrometry Q-TOF-MS identified five surfactin and two iturin isoforms produced by B. velezensis MO13. This study demonstrates significant progress on BSF production using industrial waste as a microbial substrate, surpassing reported concentrations in the literature.

Study on the Interaction of Interfacial Tension Between Water and Oil Surfaces In The Presence of Aluminium Coated With Polyvinylpyrrolidone (PVP) Nanoparticles

Applications of nanotechnology are frequently used in the oil and gas sector. However, nanoparticles boost sand consolidation, lower interfacial tension between water and oil, and improve the mobility of trapped oil to increase crude oil recovery in enhanced petroleum recovery (EOR). Using aluminium PVP-coated low-porosity sand packing, the effects of nanoparticles on interfacial tension and water-oil surface contact were examined in this study. The horizontal column was filled with low-porosity sand, and the nanopowders were suspended in deionized water. The four distinct nanoparticle suspension pore volumes (PV) used in this experiment are 0.25, 0.5, 0.75, and 1.0 PV. At the column's output, the sample is then deposited, and the effluent is analysed and contrasted using IFT and viscosity with a solid viscometer. In this investigation, it was discovered that the water target zone had a very limited pore volume and only received 0.52 PV of injected nanoparticles. The better the oil can be extracted, the lower the viscosity and IFT value. The removal of the oil droplet and increased oil output for EOR could result from the transport of PVP nanoparticles coated with aluminium.

Density functional theory investigation of the contributions of π-π stacking and hydrogen bonding with water to the supramolecular aggregation interactions of model asphaltene heterocyclic compounds

ContextA complex supramolecular process involving electrostatic and dispersion interactions and asphaltene aggregation is associated with detrimental petroleum deposition and scaling that pose challenges to petroleum recovery, transportation, and upgrading. The homodimers of seven heterocyclic model compounds, representative of moieties commonly found in asphaltene structures, were studied: pyridine, thiophene, furan, isoquinoline, pyrazine, thiazole, and 1,3-oxazole. The contributions of hydrogen bonding involving water bridges spanning between dimers and π-π stacking to the total interaction energy were calculated and analyzed. The distance between the planes of the aromatic rings is correlated with the π-π stacking interaction strength. All the dimerization reactions were exothermic, although not spontaneous. This was mostly modulated by the strength of the hydrogen bond of the water bridge and the π-π stacking interaction. Dimers bridged by two water molecules were more stable than those with additional water molecules or without any water molecule in the bridge. Energy decomposition analysis showed that the electrostatic and polarization components were the main stabilizing terms for the hydrogen bond interaction in the bridge, contributing at least 80% of the interaction energy in all dimers. The non-covalent interaction analysis confirmed the molecular sites that had the strongest (hydrogen bond) and weak (π-π stacking) attractive interactions. They were concentrated in the water bridge and in the plane between the aromatic rings, respectively.MethodsThe density functional ωB97X-D with a dispersion correction and the Def2-SVP basis set were employed to investigate supramolecular aggregates incorporating heterocycles dimers with 0, 1, 2, and 3 water molecules forming a stabilizing bridge connecting the monomers. The non-covalent interactions were analyzed using the NCIplot software and plotted as isosurface maps using Visual Molecular Dynamics.

Optimization of Oil Recovery in Clay formation: An Experimental Study on the Impact of Salinity in Waterflooding Experiments

Due to the need to enhance petroleum and gas recovery, scientists and engineers constantly seek various ways of enhancing recovery especially during water flooding process. Salinity of the water injected and type of core material studied from the formation are key factors that can enormously impact on the oil recovery. The knowledge of the impact of salinity on oil recovery during water flooding using core samples containing clay, unfortunately, has been limited. This paper investigated the impact of salinity on oil recovery carried out using two core samples obtained from shale rocks. The core sample labelled A was from Kogi state and core B was from Rivers state. Initially both core samples were dried in an oven at 88°C to cause natural fractures and connect the pore spaces then saturated with brine of 20g/l salinity and light crude oil of viscosity 3.35cp to simulate reservoir conditions within the core samples. The porosity of the samples was determined by liquid saturating method and the effective permeability was calculated using Darcy’s law. Core flooding tests were conducted by injecting brine and varying the salinity levels at 10g/l to 50g/l to displace 20 ml of light crude oil originally saturated in each core sample. The results and analysis of the tests showed that the core sample B recovered more oil than sample A. The recovery factor efficiency of core A was 24%, 31.5%, 51%, 53% and 53.5% and the core sample B was 26%, 42%, 50.8%, 52.1%, 55%. The oil recoveries at breakthrough increased significantly with increasing salinity. The difference in oil recoveries for both core samples was observed at 30g/l of brine salinity where core B recovered 8.8% higher than core A. At 50g/l brine salinity, the oil recovery efficiency did not change for both core samples while changing the concentration of brine relative to the initial brine used. The findings of this study and the data retrieved shows the improvement of oil recovery factor increases as brine salinity increases which can be attributed to interfacial tension reduction and viscosity alteration.

Influence of extractable organic components on shale wettability: Dongyuemiao member of Jurassic Ziliujing formation in the Fuxing area, Eastern Sichuan Basin

The wettability of reservoir rocks is a critical factor for the petroleum exploration and recovery, which plays an important role on relative permeability, capillary pressure, and ultimate recovery. This study aims to characterize the difference in wettability before and after soxhlet extraction, and reveal the influences of mineral composition, pore structure and extractable organic components on wettability of shales with different lithofacies. Several organic shale samples from the Dongyuemiao (DYM) section of the Jurassic Ziliujing (ZLJ) formation were collected to investigate the mineral composition, pore-size distribution, wettability characteristics and determine the main controlling factors on wettability alteration. Pore type and abundant are observed using argon ion polishing scanning electron microscopy. The pore volume (PV) and pore size distribution (PSD) characteristics before and after extraction were obtained using a combination of nitrogen physisorption and high-pressure mercury intrusion porosimetry (MIP). Spontaneous imbibition (SI) and nuclear magnetic resonance (NMR) experiments were used to investigate the wettability characteristics before and after extraction.Results show that clay, quartz and calcite are dominant minerals in the DYM shales, and three typical lithofacies are identified, including mixed shale (M), argillaceous shale (CM) and calcareous shale (C). Clay mineral interP pore is the dominant pore type in the DYM shales, followed by organic matter (OM) pore. Before the extraction, the DYM shale is more oil lipophilic, while its wettability alters slightly after the extraction. The M shales and C shales maintain lipophilic, while as the CM shales alters from oil wet to mixed wet. Samples with higher quartz have better connectivity of the hydrophilic and lipophilic pore networks, and carbonate minerals play an opposite role. During the extraction process, polar solvents could react with clay minerals to cause pore space expansion, which enhances the water wettability after extraction. Due to the low OM content and poor organic clay complex related pores in the study area, clay minerals have not significant correlation with oil wettability, but influence the water wettability. No correlation occurs between total organic carbon (TOC) content and oil/water wettability of shales before and after extraction. In comparison, macropore has a significant impact on water wettability, while micropore and mesopore play significant impact on oil wettability.

Artificial intelligence-based framework for precise prediction of asphaltene particle aggregation kinetics in petroleum recovery

The precipitation and deposition of asphaltene on solid surfaces present a significant challenge throughout all stages of petroleum recovery, from hydrocarbon reservoirs in porous media to wellbore and transfer pipelines. A comprehensive understanding of asphaltene aggregation phenomena is crucial for controlling deposition issues. In addition to experimental studies, accurate prediction of asphaltene aggregation kinetics, which has received less attention in previous research, is essential. This study proposes an artificial intelligence-based framework for precisely predicting asphaltene particle aggregation kinetics. Different techniques were utilized to predict the asphaltene aggregate diameter as a function of pressure, temperature, oil specific gravity, and oil asphaltene content. These methods included the adaptive neuro-fuzzy interference system (ANFIS), radial basis function (RBF) neural network optimized with the Grey Wolf Optimizer (GWO) algorithm, extreme learning machine (ELM), and multi-layer perceptron (MLP) coupled with Bayesian Regularization (BR), Levenberg–Marquardt (LM), and Scaled Conjugate Gradient (SCG) algorithms. The models were constructed using a series of published data. The results indicate the excellent correlation between predicted and experimental values using various models. However, the GWO-RBF modeling strategy demonstrated the highest accuracy among the developed models, with a determination coefficient, average absolute relative deviation percent, and root mean square error (RMSE) of 0.9993, 1.1326%, and 0.0537, respectively, for the total data.

Emulsion Formation in Palm Oil Methyl Ester Sulfonate Surfactant to Light Crude Oil

The Enhanced Oil Recovery method is a method that can be attempted to increase the recovery of petroleum. One of the materials that can be used is Methyl Ester Sulfonate surfactant from palm oil, as a vegetable surfactant whose raw materials are widely available in Indonesia. In this study, the compatibility test of Methyl Ester Sulfonate surfactant was carried out on light crude oil type T samples. The study was carried out with various surfactant concentrations, starting from 0.25%, 0.3%, 1%, 1.5%, and 2%. In the aqueous stability test, the results obtained for all clear conditions for the surfactant concentration were measured for 3 days in an oven with a temperature of 60oC. Whereas in the phase behavior test, good results of the upper phase emulsion were obtained at concentrations of 0.3%, 1%, 1.5%, and 2%. The volume of the top phase emulsion ranges from 25% to 37.5%. (Normal). From the results of this study, it can be concluded that for the crude oil sample T, palm oil MES surfactant is stable for use as a surfactant injection fluid, with a surfactant concentration composition that produces a fairly large upper phase emulsion of around 25% - 37.5% at a surfactant concentration of 0.5% - 2%.

An investigation of fatigue response of well cement under cyclic loading and impact on zonal isolation performance

Cyclic bottomhole pressure fluctuation is very prevalent in modern well construction and enhanced petroleum recovery applications and poses a great challenge to annular seal integrity and successful zonal isolation, even in cases where the cement seal exhibits excellent initial quality. Thus, annular sealants must be designed to mitigate or minimize the deleterious effects of cyclic pressure fluctuations on the annular seal. Optimal cement designs for this purpose require a proper understanding of damage modes and mechanisms associated with a cyclic pressure regime, as well as the impact of the cement mechanical integrity evolution on the leakage of the cemented annulus. Using four cement formulations with distinct mechanical and microstructural properties, we investigated the mechanical integrity evolution and leakage characteristics of cemented pipe specimens subjected to confinement pressure fluctuations. Via microscopic inspection of the cement/pipe interface after pressure cycling and permeability measurements during pressure cycling, we attempted to correlate cement properties with leakage and suggest a recommendation for optimal cement design and successful zonal isolation in wellbores subjected to cyclic pressure. Test data indicate that under high enough pressure variation, interfacial cracking at the cement pipe interface is unavoidable and the cement seal's ability to maintain zonal isolation will be dependent on the microstructural morphology and microscale mechanical resilience of the cement formulation. Stiffer conventional cements also appear to have a higher chance of leakage through non-interfacial fractures than their more flexible counterparts. Latex cements show great promise for effective zonal isolation under cyclic bottomhole pressure conditions and should be studied in more detail.

Microwave-assisted solvent deasphalting of heavy fuel oil and process parameters optimization

As petroleum recovery has progressed historically, the portion of heavier crudes and bottom of the barrel residues from the refining process has increased. These crudes are challenging to process, leaving vacuum residues with large fractions of ash and refractory sulfur due to high asphaltene content. Asphaltenes are known to form coke in catalytic upgraders and deactivate refining catalysts. Asphaltenes, which are present in significant amounts in heavy crudes, are the cause of reduction of combustion efficiency, clogging of refinery pipes, and particulate matter emissions. Asphaltenes can be removed from heavy crudes by solvent deasphalting. But the requirement of a high solvent to oil ratio limits its commercial viability. To lower the requirement of solvent, this study investigates deasphalting of heavy fuel oil (HFO) with n-heptane, n-hexane, and n-pentane by microwave-assisted, ultrasound-assisted, and supercritical solvent deasphalting methods. Among the different methods investigated, the microwave-assisted method was found to be more efficient and removed 88 and 80 wt% of asphaltenes from HFO with heptane and hexane, respectively. Microwave irradiation selectively heats asphaltenes in microwave transparent non-polar solvents and increases the degree of collision of asphaltenes for aggregation and thus precipitation. Besides, resins are readily solubilized by the solvent under microwave heating and thus they are unable to act as peptizing agents of asphaltenes. The optimization of process parameters such as solvent to HFO ratio, microwave power, and holding time was investigated for microwave-assisted deasphalting using Central Composite Design (CCD) and artificial neural network (ANN). The optimum removal of asphaltene was observed when the solvent to HFO ratio, microwave power, and holding time were kept at 3, 150 W, and 20 min, respectively. Deasphalting also significantly improved the quality of HFO by dropping the viscosity along with the sulfur and nitrogen contents of HFO. The outcomes of this study are significant for the petrochemical industry as potentially improved crude oil processing with lower solvent to HFO ratios can be achieved in a more effective, economical manner using microwave assistance.

Anticorrosion performance of 1–benzylimidazole and synergistic iodide additives on C1018 carbon steel in 15% HCl solution

Acidizing, an industrial practice to enhance petroleum recovery, causes one of the most severe corrosion attacks on carbon steel drilling pipelines. Identifying highly efficient inhibitors to ameliorate this phenomenon is important for the petroleum industry. Here, the performance of 1–benzylimidazole (BZM) as a corrosion inhibitor for C1018 carbon steel in 15% HCl was investigated using electrochemical, weight loss and surface characterization techniques. Results from electrochemical techniques (electrochemical impedance spectroscopy (EIS), electrochemical frequency modulation (EFM), linear polarization resistance (LPR) and potentiodynamic polarization (PDP)) agree that BZM performs efficiently by providing inhibition efficiency up to 75% at 25 °C with 1200 ppm concentration. The addition of 5 mM KI significantly enhances BZM efficiency to 93% at 25 °C. BZM alone is a mixed–type corrosion inhibitor with slightly anodic behavior. The addition of KI transforms the BZM inhibition mechanism more cathodically. However, the BZM + KI efficiency decreases to 60% at 60 °C. Surface characterization by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) confirm that BZM uses its nitrogen and phenyl groups to adsorb on the steel surface, forming a thin film which mitigates localized corrosion.

Design, preparation, microstructure and tribological properties of Cr7C3 and CrxSy reinforced composite coating

Conventional rod pumping has been the dominant petroleum recovery technology for nearly a century. As key components of the rod pumping system, tubing and sucker rod coupling are often prematurely scrapped due to “rod/tubing eccentric wear”. To improve the service life of sucker rod coupling and tubing, a Cr7C3 and CrxSy reinforced γ-(Ni, Fe) matrix composite coating was designed by JMatPro simulation and the coating was prepared by plasma transferred arc (PTA) cladding technique. The coating has a refined microstructure composed of Cr7C3 carbide, amorphous sulfide CrxSy and γ solid solution. Primary Cr7C3 fine blocks with volume fraction up to 54% are uniformly dispersed in the coating giving the coating high hardness and good wear resistance. The in-situ synthesized CrxSy phases are dispersed in the γ matrix in the form of fine spherical particles, which endows CrxSy phases strong interfacial bonding, and allows the CrxSy particles to be stripped layer-by-layer, thereby providing continuous lubrication. The coating exhibits excellent wear resistance and low and stable friction coefficient, and is expected to serve as a protective coating for sucker rod coupling to simultaneously improve the service life of sucker rod coupling and tubing.

Bacterial co-occurrence patterns are more complex but less stable than archaea in enhanced oil recovery applied oil reservoirs

A complex microbial community exists in oil reservoirs after the application of chemical enhanced oil recovery (EOR) technologies, where the dynamic interactions of microorganisms are thought to be critical to petroleum composition, recovery, and production technologies but are poorly understood. Here, we used the 16S rRNA gene to construct co-occurrence networks for bacterial and archaeal communities associated with water-, polymer-, and alkaline surfactant polymer (ASP)-flooded oil reservoirs. Nonmetric multidimensional scaling analysis showed that bacterial and archaeal community structures differed significantly (p < 0.01) among the oil reservoirs with different EOR compositions. The microbial co-occurrence pattern in water-flooded reservoirs was more complex, with more nodes, edges, and average degrees (i.e., average links per node in the network) than in the polymer- and ASP-flooded reservoirs. However, the archaeal co-occurrence pattern maintained a more robust structure than that of bacteria under the application of polymer and ASP flooding technologies, suggesting that the application of different enhanced oil recovery techniques has diverse effects on the bacterial and archaeal co-occurrence patterns in reservoirs. The pH and [HCO3−] were significantly correlated with the variations in bacterial and archaeal network structures. Our findings provide new insights into the response of microbes to diverse EOR processes by regulating their interactions in deep oil reservoirs. Revealing the effects of water, polymer, and ASP flooding on the co-occurrence patterns of bacteria and archaea in oil reservoirs, which may facilitate the implementation of microbial enhanced oil recovery technology in the future.

Regulator Analyzes Australia’s Decommissioning Challenge

_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 208483, “Is Australia Prepared for the Decommissioning Challenge? A Regulator’s Perspective,” by David Christensen and Andrew Re, National Offshore Petroleum Safety and Environmental Management Authority. The paper has not been peer reviewed. _ The Australian offshore petroleum industry has been in operation since the early 1960s and at the time of writing has approximately 57 platforms, 11 floating facilities, 3500 km of pipelines, and 1,000 wells in operation. Many offshore facilities are now approaching the end of their operational lives. Modeling has estimated Australia’s combined offshore petroleum industry decommissioning liability (including wells, pipelines, subsea equipment, and facilities) to be $40.5 billion. The purpose of the complete paper is to highlight the importance and benefit of adopting best practices when planning for decommissioning throughout the life cycle of a petroleum project. Introduction Australia’s offshore petroleum decommissioning challenge is significant given its remote location, limited availability of specialist services, and the relative infancy of its offshore industry in undertaking large-scale decommissioning projects. Recent events in Australia have shown that the industry is, broadly speaking, unprepared for decommissioning. Australian Regulatory Approach The Offshore Petroleum and Greenhouse Gas Storage (OPGGS) Act of 2006 and associated regulations provide the legal framework for the exploration and recovery of petroleum and greenhouse gas activities in Australian Commonwealth waters (those areas that are more than 3 nautical miles from the territorial sea baseline). The key principle underpinning the OPGGS Act and regulations is that responsibility for ensuring the health and safety of workers and the protection of the environment lies with those who create the risks. An objective-based regulatory regime sets requirements that must be achieved but does not prescribe how those requirements must be met. The National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) has been established and appointed under the OPGGS Act as regulator for health and safety, structural (well) integrity, and environmental management of petroleum activities in Australian waters (3–200 nautical miles offshore) and in coastal waters (0–3 nautical miles offshore) where regulatory powers and functions have been conferred. Section 572, Maintenance and Removal of Property. Section 572 of the OPGGS Act establishes requirements for maintenance and removal of property by the titleholders, along with exemptions and obligation provisions. Section 572(2) of the OPGGS Act provides that a titleholder must maintain in good condition and repair all structures that are, and all equipment and other property that is, in the title area and used in connection with operations. Section 572(3) of the OPGGS Act provides that a titleholder must remove from the title area all structures that are, and all equipment and other property that is, neither used nor to be used in connection with the operations in which the titleholder is or will be engaged.

Catalytic capacity evolution of montmorillonite in in-situ combustion of heavy oil

Clay minerals such as montmorillonite are significant in petroleum storage and recovery. Montmorillonite (Mt) is a natural solid acid catalyst containing Brønsted and Lewis acid sites and can catalyze heavy oil oxidation (HOO) during in-situ combustion (ISC). However, its catalytic activity largely depends on the heating process of heavy oil. In the study, the catalytic capacity evolution of Mt in ISC of heavy oil was explored with the isoconversional method and thermal analysis. In low-temperature oxidation (LTO) and high-temperature oxidation (HTO) stages, the addition of Mt largely reduced the peak temperatures (Tpeak) of DTA and DTG and the Tpeak of H2O (LTO and HTO stages) and CO2 (HTO stage) in HOO. Notably, Mt did not always show the positive catalytic effect. In LTO stage, the thermal transformation process had a small effect on DTA Tpeak, Tpeak of H2O and CO2, and the reaction activation energy (Eα) of HOO. In HTO stage, the catalytic effect of Mt on HOO was related to its thermal transformation process, especially interlayer water (IW) dehydration and dehydroxylation. In HTO stage, the IW dehydration process of Mt showed the strongest catalytic effect on HOO, significantly reduced DTA Tpeak and Eα, and resulted in the lowest Tpeak of H2O and CO2. The dehydroxylation process of Mt also showed a certain effect, whereas the overlapping process between the dehydration (IW) reaction and partial dehydroxylation reaction of Mt had no positive catalytic effect on HOO. DTA, TG-FTIR, and non-isothermal kinetic analysis further confirmed that the catalytic capacity of Mt in HTO stage was improved by IW dehydration process of Mt and weakened by the dehydroxylation process of Mt.

Applicable Investigation of SPH in Characterization of Fluid Flow in Uniform and Non-Uniform Periodic Porous Media

Today, the use of numerical modeling for characterizing properties of porous media and related concepts has been widely extended, especially in subsurface flow issues such as geological CO2 storage and petroleum recovery. Therefore, in this study, the fundamental problem of laminar fluid flow through uniform or non-uniform and periodic array of cylinders was functionally investigated using the smoothed particle hydrodynamics (SPH) method as a modern and applied method of modeling in order to develop the past studies and introduce a complementary numerical tool alongside laboratory methods. All modeling processes were performed in the form of dimensionless processes for generalization and applicability at different scales. The results were used to characterize properties of porous media and to investigate basic properties such as fluid velocity, permeability, streamlines, and hydraulic tortuosity. Accuracy of modeling was shown in comparison with the results obtained in the literature. In this study, the potential of the method has been investigated in order to show the ability in modeling characteristic laboratory experiments of porous media and the possibility of using it instead of them. For this purpose, three periodic models of uniform and randomly distributed non-uniform porous media with arrays of circular, square, and diamond-shaped cylinders in a porosity range of 30–95%, with different types of cylinder distribution at the pore scale, were investigated. New equations were proposed for permeability as a function of porosity. Moreover, the method of tortuosity calculation was investigated directly through the time history of properties in the SPH method, and shape factors were obtained for the studied porous media models. The results showed that the geometry of a square cylinder with distribution in a square grid led to a higher permeability than circular and diamond-shaped grids. In contrast, diamond-shaped geometry with distribution in a hexagonal grid led to higher permeability than the other two models. Furthermore, diamond-shaped geometry had higher tortuosity, and circular and square geometries had almost identical tortuosity. Increasing the size of the modeling domain and decreasing the size of cylinders (i.e., decreasing resolution) reduces effects of the shape and the geometry of cylinders and achieves the same results. Random and non-uniform distribution of cylinders within porous media reduces fluid velocity, permeability, tortuosity, and shape factor (p) compared to the uniform models.

EVALUASI PENGARUH LAJU ALIR POMPA INJEKSI TERHADAP TEKANAN POMPA INJEKSI PADA STASIUN PENGUMPUL UTAMA B JATIBARANG FIELD

After a certain period of time, the reservoir's pressure will drop to the point where petroleum can no longer flow naturally. Because of the decrease in oil production, a well will no longer have economic value. Artificial lifts or specific methods are used in wells to help oil flow to the surface in order to maintain or increase petroleum recovery. Water injection is a method of increasing oil recovery by injecting water into the well. Water injected into this well will increase pressure to the oil in the reservoir, causing it to be pushed and flow to the surface. Water treatment is typically performed at a Water Treatment Injection Plant (WTIP). WTIP performance is an activity that is used to keep reservoir pressure constant. The separation of the water that is lifted with the oil is the first step in the WTIP process. The Jatibarang Field fluid is collected at the SPU (Main Collector Station). Water from various wells will be collected at the SPU A, SPU B, SPU-Cemara, and Balongan terminals. At WTIP SPU B, the injection pump flow rate and injection pressure have a linear or directly proportional relationship. This is because as the injection pump flow rate increases, the amount of water injected increases, causing the pressure to increase. The flow rate is influenced by the amount of water received at SPU B, the condition of the pump, and the line connecting the SPU and WTIP.

PH mediated assemblage of carbon, nitrogen, and sulfur related microbial communities in petroleum reservoirs.

Microorganisms are the core drivers of biogeochemistry processes in petroleum reservoirs and have been widely used to enhance petroleum recovery. However, systematic information about the microbial communities related to the C-N-S cycle in petroleum reservoirs under different pH conditions remains poorly understood. In this study, 16S rRNA gene data from 133 petroleum samples were collected, and 756 C-N-S related genera were detected. The Chao1 richness and Shannon diversity indices for the C-N-S-related microbial communities showed significant differences among different pH conditions and at the lowest levels in acidic conditions with pH values of 4.5–6.5. In addition, pH was the most important factor influencing the C-N-S related microbial communities and contributed to 17.95% of the variation in the methanogenesis community. A total of 55 functional genera were influenced by pH, which accounted for 42.08% of the C-N-S related genera. Among them, the genera Pseudomonas and Arcobacter were the highest and were concentrated in acidic conditions with pH values of 4.5–6.5. In parallel, 56 predicted C-N-S related genes were examined, and pH affected 16 of these genes, including putative chitinase, mcrA, mtrB, cysH, narGHIVYZ, nirK, nirB, nifA, sat, aprAB, and dsrAB. Furthermore, the co-occurrence networks of the C-N-S related microbial communities distinctly varied among the different pH conditions. The acidic environment exhibited the lowest complex network with the lowest keystone taxa number, and Escherichia-Shigella was the only keystone group that existed in all three networks. In summary, this study strengthened our knowledge regarding the C-N-S related microbial communities in petroleum reservoirs under different pH conditions, which is of great significance for understanding the microbial ecology and geochemical cycle of petroleum reservoirs.

Synthesis and application of titanium dioxide photocatalysisfor energy, decontamination and viral disinfection: a review.

Global pollution is calling for advanced methods to remove contaminants from water and wastewater, such as TiO2-assisted photocatalysis. The environmental applications of titanium dioxide have started after the initial TiO2 application for water splitting by Fujishima and Honda in 1972. TiO2 is now used for self-cleaning surfaces, air and water purification systems, microbial inactivation and selective organic conversion. The synthesis of titanium dioxide nanomaterials with high photocatalytic activity is actually a major challenge. Here we review titanium dioxide photocatalysis with focus on mechanims, synthesis, and applications. Synthetic methods include sol-gel, sonochemical, microwave, oxidation, deposition, hydro/solvothermal, and biological techniques. Applications comprise the production of energy, petroleum recovery, and the removal of microplastics, pharmaceuticals, metals, dyes, pesticides, and of viruses such as the severe acute respiratory syndrome coronavirus 2.