Chemistry and Technology of Fuels and Oils
Journal Prestige (SJR): 0.19 Number of Followers: 1 Hybrid journal (It can contain Open Access articles) ISSN (Print) 1573-8310 - ISSN (Online) 0009-3092 Published by Springer-Verlag [2468 journals] |
- Studying the Accumulation Characteristics of Crude Oil in an Oil Formation
in the Aspect of Predicting the Effectiveness of Crude Oil Exploration-
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Abstract: The development of tight oil sandstones in the Extension Formation in the southwestern Ordos Basin and the mode of crude oil migration is a hotspot. A large number of geochemical experiments and computational methods were used to systematically study the crude oil transport characteristics of the Yanchang Formation in the Huaqing area. The results show that four typical types of inclusions are developed in the Yanchang Formation: inclusions in quartz fissures, inclusions in quartz colluvium and large rims, inclusions in calcareous colluvium, and inclusions in sodium feldspar. There are two peaks in the homogenization temperature of the inclusions: 80-100°C and 120-130°C. The Chang 6 and Chang 8 reservoirs in the Huaqing area have experienced the process of densification while forming reservoirs, and the physical properties of the sand body reservoirs during the maximum hydrocarbon discharge period are good, which is an effective channel for oil and gas transportation. The minimum oil column heights for oil and gas transportation in Chang 6 and Chang 8 Members are 7.48m and 15.68m, respectively. Proximity vertical transportation is an important mode of crude oil transportation and aggregation in the Yanchang oil group in the Huaqing area. The physical properties of crude oil in Huaqing area are good, showing low density, low viscosity, low freezing point and good fluidity. The hydrocarbon source rocks of the Chang 7 Member were transported under excess pressure and buoyancy along channels such as cheese root networks, connected sands and microfractures, and thus large composite lithologic reservoirs were formed in the Chang 6 and Chang 8 Members.
PubDate: 2024-07-24
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- Research on the Physical Strength of Surface Conductor Soil Under Deep Jet
Drilling-
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Abstract: The installation of a surface conductor in deepwater jet drilling is crucial for offshore oil and gas development. This study investigates the interaction between the surface conductor and subsea soil during injection drilling. A simplified model using ABAQUS finite element software analyzes the damage effect of the water jet on the soil and simulates the mechanism of soil body damage under different parameters. The mechanical behavior of the soil and conductor during installation is examined, and the load-bearing characteristics of the soil are analyzed. Sensitivity analysis of factors such as injection displacement and bit extension reveals their significant influence on conductor installation. The findings provide insights into the drilling process and contribute to ensuring the stability of the wellhead in deepwater drilling operations.
PubDate: 2024-07-24
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- Research on Oil Production Forecasting Method of Tight Oil Reservoir Based
on Grey Correlation Method-
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Abstract: Horizontal well fracturing technology is an important way to improve the oil recovery efficiency of low-permeability reservoirs. Aiming at a certain test area on the edge of Daqing oilfield, a simulation conceptual model is established using CMG reservoir numerical simulation software. The influence of engineering parameters such as the number of fracture clusters, fracture half-length, fracture permeability, production pressure difference on the peak daily oil production is analyzed. Moreover, the gray correlation method is used to analyze the influence of the above factors on the peak daily oil production. Using key factors as variables in the regression model, a mathematical prediction model for daily oil production peak is established. The findings should make an important contribution to the oil production peak prediction.
PubDate: 2024-07-24
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- Characterization of Pore Structure and Oil-Water Two-Phase Seepage
Properties in Sandstone Reservoirs-
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Abstract: In this study, the pore structure and oil-water phase seepage characteristics of sandstone reservoirs of the Yanchang Formation in the Ordos Basin were deeply analyzed. Through scanning electron microscopy observation, oil-water phase percolation experiments and nuclear magnetic resonance (NMR) experiments on 30 core samples, the pore structure was categorized into uniform macroporous, striated, microfractured and dense types. The experimental results show that the uniform macroporous type pore structure shows the strongest seepage capacity, and its ratio of liquid-measured to gas-measured permeability is 0.724 on average, while the dense type pore structure has the weakest seepage capacity, and the ratio is 0.091 on average; NMR T2 spectral analysis reveals that the cores with different types of pore structure show significant characteristic differences in the water-driven oil drive process, especially in the substitution of oil in the macroporous and micrometer pore In particular, the oil substitution in large pores and micron pores is remarkable, that is, the oil-water seepage process and the response of seepage and suction of cores with different types of pore structure are obviously different, which is a better way to study the characteristics of oil-water seepage and distribution of oil and water; the uniform macroporous type and the striptype pore structure are more effective in oil-water two-phase seepage, and the microfracture type and the dense type are relatively poor. This paper provides a basis for the exploitation of tight reservoirs in the study area, which is of great theoretical and practical significance for optimizing the oilfield development strategy and improving the efficiency of oil and gas exploitation.
PubDate: 2024-07-23
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- Simulation Analysis of Wellbore Instability Considering the Influence of
Hydration Effect on the Physical Properties of Brittle Shale-
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Abstract: Shale gas, as an important unconventional oil and gas resource, its efficient development can alleviate the current severe energy demand situation. However, the water absorption and expansion characteristics and hydration effects of shale pose a great threat to the drilling safety of shale, mainly wellbore stability. Therefore, based on mechanical property experiments, the influence of hydration expansion on the mechanical property parameters of brittle shale was analyzed, and an evolution model of the mechanical property parameters of shale with hydration expansion was constructed. In addition, a finite element model for numerical simulation of wellbore stability in shale formations was established, and the effects of factors such as the addition of hydration inhibitors in drilling fluid on wellbore collapse were analyzed. Research has shown that the hydration and expansion of shale can reduce its elastic modulus and cohesive force, but the effect of hydration and expansion on Poisson’s ratio and internal friction angle shows the opposite pattern. After being immersed in drilling fluid for 12 hours, the elastic modulus of shale decreased from 5.3 GPa to 3.9 GPa, and the cohesion decreased from 4.6 MPa to 3.0 MPa. In addition, wellbore collapse and instability in shale mainly occur in the early stages of drilling operations, while wellbore collapse will significantly slow down in the later stages. The wellbore enlargement rate increased to 40% within the first three hours of drilling operations. Moreover, the addition of hydration inhibitors in drilling fluids will prevent further collapse of the wellbore by inhibiting the invasion of water. When the hydration inhibitor in the drilling fluid was increased from 0 to 45 g/m3, the wellbore enlargement rate decreased from 66.2% to 27.8%. This study can provide theoretical reference for maintaining wellbore stability and drilling safety during shale drilling.
PubDate: 2024-07-22
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- Catalytic Vacuum Gas Oil Oxycracking in Presence of Metal Zeolite
Catalysts-
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Abstract: The results of study of catalytic vacuum gas oil oxycracking process in presence of metal zeolite catalysts are presented. Screening of oxides of 10 modifying transition metals (Cu, Ti, V, Cr, Fe, Co, Ni, Cd, Mo, and W) made it possible to disclose the basic differences in the behavior of the catalytic systems. Based on the data obtained, an activity series were constructed (based on the total yield of light fractions): Mo > Ti > Cr > Ni > Fe >W > V > Cd > Co > Cu. Best results for the target fractions were obtained in the presence of molybdenum, titanium, and vanadium zeolite systems (for 195/200-300°C fractions) and for tungsten-containing system (for hydrocarbon gas). Comparison of vacuum gas oil conversion data obtained under catalytic oxycracking conditions with bond strength of the surface oxygen of the metal oxides made it possible to establish their correspondence and to recommend this criterion for choosing catalysts for the process.
PubDate: 2024-07-20
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- Deepwater Oil and Gas Well Annulus Pressure Management Strategy
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Abstract: Deepwater oil and gas wells have complex well body structure, and the multi-layer closed annulus structure formed by free section and sealed section tubing column is easy to absorb heat and generate expansion pressure. In deepwater drilling operation, the rise in temperature of the closed casing annulus is easy to produce the phenomenon of rising annulus pressure, and due to the special characteristics of the underwater wellhead device, it is not possible to release the annulus pressure between the casing, and the high annulus pressure will lead to casing extrusion and deformation, which will seriously threaten the safety and integrity of the wellbore. In order to ensure the smooth progress of deepwater drilling operations and reduce operational risks, corresponding methods and strategies are proposed for the management of annulus pressure in deepwater oil and gas wells. A variety of measures and products have been developed worldwide for engineering measures of annulus pressure management, including optimization of well structure and cementing design, use of rupture discs, foam casing and vacuum tubing, and other measures. This paper analyzes five major categories of prevention methods and control techniques for deepwater oil and gas wells well annulus confinement pressure, which are increasing casing strength (stiffness level, wall thickness), eliminating expanding fluid, blocking heat transfer, balancing fluid thermal expansion and releasing annulus confinement pressure management strategies. Measures to control annulus pressure by increasing casing strength (stiffness level, wall thickness), fully sealing the annulus, vacuum insulated tubing, foam casing, nitrogen foam isolation fluid, non-circumferential pipe shoes and rupture disc casing tools and analyzing their engineering advantages and disadvantages. According to the engineering application experience, the use of rupture disk casing tool to alleviate the annular pressure is currently the most widely used and stable and reliable means in the world. And according to the theoretical knowledge and engineering practice of annular pressure management, the basic strategy of annular pressure management is summarized when rupture disk is adopted as the main means of annular pressure management.
PubDate: 2024-07-20
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- How to Improve the Efficiency of Kinetic Hydrate Inhibitors Based on
Nanofibrillar Cellulose'-
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Abstract: This research discovered that carboxylated cellulose nanofibrils (CNF) with cations of various structures can significantly reduce the number of nucleation sites for methane hydrate formation when compared to distilled water. The electrokinetic potential of CNF in water slightly affects the concentration of hydrate crystallization centers, but it does alter the work of their formation. The energy barrier increases as the absolute value of the electrokinetic potential of nanoparticles decreases. The study of the effect of various CNF salts on the kinetics of methane hydrate formation expands our understanding of the inhibition mechanism of hydrate formation. It’s assumed that a significant negative charge prevents the adsorption of like-charged hydrate nucleation centers on CNF. A decrease in the absolute value of zeta potential of CNF due to a change in cation facilitates this process. As a result, nuclei sorbed on colloidal CNF particles are stabilized on the surface, complicating their coalescence and crystal growth. The design of cellulose-based nanoparticles with varying zeta potential will allow the development of a colloid theory for controlling the formation of gas hydrates.
PubDate: 2024-07-19
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- Research on Shale Reservoir Characterization and Control Factors
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Abstract: This study focuses on the characterization of shale gas reservoirs in the Longmaxi Formation and their controlling factors in the east Sichuan Basin. Detailed mineralogical and reservoir characterization of shale samples in the region was carried out by various methods, including X-ray diffraction analysis and nitrogen adsorption experiments. The results show that the shale is mainly composed of clay minerals (illite content ranges from 34.9% to 55.7%), quartz and calcite. In terms of reservoir characteristics, the shale mesopore morphology is mainly “slit-type”, with BET specific surface area ranging from 7.12-25.63 m2/g and BJH pore volume from 0.0095-0.0262 mL/g. These reservoir characteristics show a significant positive correlation with the organic carbon content (1.82-3.87%). correlation. Petrographic analysis further reveals that the brittle mineral content has a significant effect on the brittleness, pore development and fracturing effectiveness of the rocks. In addition, diagenesis (including compaction, cementation, dissolution, and thermal evolution of organic matter) had a significant impact on the formation and characterization of shale pores. These findings provide a key scientific basis for understanding the geological characteristics and development potential of shale gas reservoirs in the Longmaxi Formation in the Sichuan Basin.
PubDate: 2024-07-19
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- Silicoaluminophosphate Molecular Sieves with Different Silica Contents and
Their Catalytic Properties in the Oligomerization of α-Methylstyrene-
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Abstract: Silicoaluminophosphate molecular sieves SAPO‑11 were obtained from gels with different silica contents. Silicoaluminophosphates as cubic crystals with 0.5 mm diameter were obtained from gels with SiO2/Al2O3 ratio equal to 0.1, while samples with the ratio SiO2/Al2O3 = 0.5 were obtained as extended prisms with 1‑2 mm diameter. Increasing the SiO2/Al2O3 ratio from 0.1 to 0.4 leads a greater amount of acid sites and a decrease in the specific surface. The conversion of a‑methylstyrene as well as the yield of linear dimers and cyclic trimers both increase with an increasing amount of acid sites and greater external surface.
PubDate: 2024-07-19
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- A Promising Device Based on Step Stage Theory for Highly Effective
Treatment of Oil Field Wastewater-
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Abstract: This study proposed a solar thermal electrochemical photo (STEP) theory-based integrated device for highly efficient oilfield-produced wastewater (OPW) purification, combining photothermal and electric technologies. The major oil fields in China reaching the mid-to-late stage of high-water content extraction have substantially increased the amount of OPW, the complex composition of which makes degradation challenging. This research aimed to improve OPW treatment efficiency and reduce energy consumption and mining costs via innovative processes and integrated experimental devices. A solar five-field demulsification model was developed by combining filtration, distillation, condensation, and other processes using the solar STEP theory and incorporating the photocatalytic oxidation, thermal effect, electro-oxidation, air flotation, and flocculation derived from solar energy. The model enables the utilization of photocatalysts to harness solar power.and get the full spectrum energy hierarchical conversion utilization. The results showed that petroleum hydrocarbon removal was positively correlated with the environmental temperature and voltage. The device significantly improved the petroleum hydrocarbon removal rate at an optimized temperature and voltage. At 100°C and 3 V, the petroleum hydrocarbon removal rate reached 93%, confirming the efficiency and feasibility of the device in improving OPW treatment efficacy and environmental protection.
PubDate: 2024-07-19
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- The Activity of Trimetallic Catalysts in the Hydrotreating of a Mixed
Diesel Fraction-
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Abstract: A study was carried out on the effect of the nature of the support, composition of the active phase, and heat treatment conditions on the activity of trimetallic Ni‑Co‑Mo catalysts in the hydrotreating of a mixed diesel fraction. Temperature‑programmed desorption was used to show the effect of the amount and strength of the acid sites of the support on the activity of catalysts with the same elemental composition. We established the nickel‑to‑cobalt as well as phosphorus‑to‑molybdenum ratios in these trimetallic hydrotreating catalysts corresponding to the greatest desulfurization and minimum formation of polycyclic aromatic hydrocarbons in the hydrogenate.
PubDate: 2024-07-19
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- Oxidation of Oil Distillate and Deasphaltisate Organosulfur Compounds in
the Presence of Vegetable Oils-
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Abstract: The paper presents a technology for producing base oil by oxidizing organosulfur compounds, contained in petroleum distillates and deasphaltisates, with hydrogen peroxide in the presence of vegetable (rapeseed and castor) oils, followed by extraction of oxidates and dewaxing of raffinates. Extraction of the resulting oxidized mixture (oxidate) was carried out with N-methylpyrrolidone. The content of rapeseed oil contained in the raffinate and extract was determined. The extract solution from a medium-viscosity oil distillate was cooled to obtain a secondary raffinate represented by a sulfoxide concentrate. The secondary raffinate was used as a base oil for producing a lubricant with high tribological properties for use in heavily loaded friction units. The rapeseed oil remained in the raffinate improves its viscosity index and lubricating properties. The raw materials and obtained raffinates were analyzed to assess their physicochemical and tribological properties.
PubDate: 2024-07-01
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- Study of Petrolatum Deoiling Process for Obtaining Petroleum Ceresins
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Abstract: The process of getting petroleum ceresins by deoiling residual dewaxing raffinates with solvents was investigated. The relationships between the key ceresin quality and deoiling process parameters, such as composition and solvent to feedstock ratio, final cooling and filtration temperatures, and number of deoiling stages were determined. The influence of the increase in deoiling stages on the key quality characteristics and the yield of petroleum ceresins is shown.
PubDate: 2024-07-01
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- Genesis of Deep Abiogenic Hydrocarbon Systems
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Abstract: Deep hydrocarbon systems form through transformation of high-temperature deep fluids, which comprise mixtures of various volatile compounds. These processes determine the elemental and group composition of crude oil and natural gas. According to available data, deep fluids represent mixtures of methane, hydrogen, water, carbon dioxide, carbon, hydrogen sulfide, elemental sulfur, NO2, and metal-containing structures. Methane, the main component of deep fluids, is generated in large quantities in the Earth’s interior. Since some components of these mixtures exhibit catalytic activity in the processes of hydrocarbon polymerization, it can be assumed that deep fluids constitute a natural catalytic system. Elemental sulfur present in deep fluids possesses catalytic properties, thus being capable of triggering polymerization processes. This leads to the formation of high-molecular hydrocarbon and organosulfur structures. Metals in deep fluids, particularly vanadium as a catalyst, also trigger the formation of high-molecular complexes, such as porphyrins. Due to incorporation of sulfur and vanadium into crude oils, they become the largest concentrators of these elements. The variability of the ratio of these elements in deep fluids and their redox character affects the intensity of hydrocarbon polymerization processes and formation of organosulfur compounds and metal complexes. This leads to generation of either crude oils with various sulfur and metal contents or natural gas systems.
PubDate: 2024-07-01
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- Efficiency of the Action of Multifunctional Additives in Lubricating Oils
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Abstract: A study was carried out on benzyl alkoxycarbonyl methyl disulfides as multifunctional additives to lubricating oils. Results are given for testing the anticorrosion, anti-wear, anti-microbial action of previously synthesized benzyl alkoxycarbonyl methyl disulfides containing several functional groups. Efficiency was demonstrated for a series of benzyl alkoxycarbonyl methyl disulfides. Depending on their composition and structure, these disulfides improve the anticorrosion, anti-wear, and antimicrobial properties of oils. The antimicrobial properties of these compounds were studied as components of M-11 oil. The synthesized compounds in concentration 0.5-1.5 mass % enhance the resistance of mineral oil to biological damage and also display antimicrobial and antifungal activity. These compounds are more efficient than sodium pentachlorophenolate, which is a commonly used biocide. Testing in a four-ball friction machine indicates that these compounds possess anti-wear properties. Our derivatograph data on the thermal stability of these additives are in accord with the results of thermoanalytical testing of commercial additives.
PubDate: 2024-07-01
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- Numerical Simulation Investigation of Vertical Bearing Characteristics of
Deep Water Expandable Surface Conductor-
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Abstract: Deep water areas with soft subsea soils, conventional surface conductor into the mud depth is too deep, long waiting time for resting, prone to surface conductor sinking and submerged wellhead instability. In this paper, based on the basic principles of mechanics and the understanding of the structure of the surface conductor, a mechanical model of the bearing capacity of the surface conductor is established. Three types of expandable surface conductors were designed by changing the distribution of the expansion material, in contrast to conventional surface conductors. The bearing characteristics of different structural surface conductors are also investigated by changing the soil parameters from the strength of the submarine soil. The study has obtained: the load-bearing capacity comparison graph between conventional surface conductor and expandable surface conductor; the load-bearing capacity change of expandable surface conductor under the change of soil parameters and the change of expansion material section; and the load-bearing capacity improvement effect of the three expandable surface conductors designed in the paper compared with conventional surface conductors, using stress as the evaluation criterion. This paper provides technical support for the design of expandable surface conductors and provides a basis for numerical simulation of surface well construction.
PubDate: 2024-07-01
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- Petrology and Physical Characterization of Sandstone Reservoirs
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Abstract: The aim of this study is to investigate the petrological characteristics of the Jurassic Sangonghe Formation reservoirs in the Junggar Basin, Northwest China, and their physical characteristics in order to optimize the strategy of oil and gas exploration and development. Through the collection and analysis of core samples, this study systematically investigated the types, structural characteristics and pore-permeability relationships of the reservoir sandstones by using rock cast thin section analysis, pore structure delineation test by piezomercury method and experimental analysis by scanning electron microscopy. The results show that the sandstones in the reservoir of the Sangonghe Formation are dominated by feldspathic feldspathic sandstones and clastic feldspathic sandstones, and the maturity of the compositions is on the low side. The analysis of the rounding degree and cementation degree of the reservoir particles reveals its non-homogeneous characteristics, and the porosity and permeability show obvious positive correlation. Characterization of the pore structure of the reservoir shows that the size and distribution of the pore throat radius significantly affects the permeability, and the change of the throat has a more significant effect on the permeability. The porosity of the upper reservoir in the second section of the Sangonghe Formation ranges from 10.9% to 26.1%, with an average value of 17.6%, and the permeability ranges from 0.13 mD to 159 mD, with an average value of 24.43 mD. The characterization of the phase permeability analysis shows that the relative permeability of the oil phase decreases with the increase of the water saturation, and the relative permeability of the water phase increases, and the bound water saturation of the reservoirs in the study area is generally higher, with a range of 35.6% to 50.2%. 35.6% to 50.2%, with an average value of 41.6%, showing strong hydrophilicity. In summary, the petrological and physical characteristics of the Jurassic Sangonghe Formation reservoirs in the Junggar Basin are analyzed in detail in this study, which provides important geological data and theoretical basis for the exploration and development of oil and gas in this area.
PubDate: 2024-07-01
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- Cracking of Resinous-Asphaltene Extra-Heavy Oil Compounds on the Highly
Developed Surface of a Coal Additive-
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Abstract: The paper presents the results of cracking of extra-heavy oil in the pore space of a coal additive in a nitrogen atmosphere and in a subcritical aqueous fluid at a temperature of 365°C and a pressure of 17 MPa. The coal additive consisted of an amorphous carbon phase forming a developed microporous structure. An analysis using scanning electron microscopy and adsorption porometry established that a vapor- air modification of the coal additive changes its surface relief and leads to the development of a micro- and mesopore structure. The intrapore space of the modified coal additive contains 38.6 vol % mesopores with a specific surface area of 172 m2/g. The final products of extra-heavy oil cracking with the proposed coal additive are characterized by an increase in the content of saturated and aromatic hydrocarbons, as well as by an almost complete absence of asphaltenes. The largest hydrocarbon yield was observed during extra-heavy oil cracking in a nitrogen atmosphere. In experiments, asphaltene conversion processes are observed due to the destruction of C–C, C–N, and C–O bonds with the formation of low-boiling compounds and high-carbon substances. The largest yield of aromatic hydrocarbons is observed during cracking in a subcritical aqueous fluid, with the yield of liquid products being reduced due to intensive gas formation. The hydrocarbon composition of gases is dominated by lower alkanes, which indicates the destruction of C–C bonds.
PubDate: 2024-07-01
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- Study on the Geochemical Properties of Oil Shale and Its Mineralization
Potential-
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Abstract: With the gradual depletion of conventional petroleum resources, oil shale, as an important unconventional oil and gas resource, is of great significance to alleviate the global energy crisis and optimize the energy structure. In this study, we comprehensively assessed the organic matter abundance, type, maturity, and trace element characteristics of oil shale by collecting and analyzing oil shale samples from the Lower Permian region in the western part of the southern margin of the Junggar Basin, and by applying pyrolysis analysis and rock pyrolysis analysis. The study showed that the average value of total organic carbon (TOC) of the oil shale in the study area was 10.26%, of which 41.67% was medium-grade oil shale and 58.33% was low-grade oil shale, reflecting the overall abundance of medium-low organic matter. The average value of hydrocarbon potential was 40.83 mg/g. The hydrogen index of the oil shale samples ranged from 77 to 861.06 mg/g, with an average value of 405.56 mg/g. The organic matter type was mainly of the II1 type (humic-sapropelic type), which accounted for 75% of the total, and the analysis of the highest pyrolysis peak temperature showed that 83.33% of the samples were in the low maturity-mature stage. Trace element analyses revealed that the oil shales in the study area were formed in a terrestrialweakly reduced depositional environment. Especially, the analysis of Sr/Ba, Th/U and B/Ga ratios indicated that the oil shale was mainly formed in freshwater-semi-saline environment. In addition, the analysis of V/(V+Ni) and U/Th ratios supports the reduced environment in which the oil shale was formed. The shale in the Dalongkou area has greater salinity values and higher organic matter productivity in the water body at the time of formation compared to the oil shale in the Cangfanggou area. The results of this study are important for understanding the geochemical properties and mineralization potential of the Lower Permian oil shales in the western part of the southern margin of the Junggar Basin.
PubDate: 2024-07-01
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