The miscibility of flue gas and different types of light oils is investigated through slender-tube miscible displacement experiment at high temperature and high pressure.Under the conditions of high temperature and hi...The miscibility of flue gas and different types of light oils is investigated through slender-tube miscible displacement experiment at high temperature and high pressure.Under the conditions of high temperature and high pressure,the miscible displacement of flue gas and light oil is possible.At the same temperature,there is a linear relationship between oil displacement efficiency and pressure.At the same pressure,the oil displacement efficiency increases gently and then rapidly to more than 90% to achieve miscible displacement with the increase of temperature.The rapid increase of oil displacement efficiency is closely related to the process that the light components of oil transit in phase state due to distillation with the rise of temperature.Moreover,at the same pressure,the lighter the oil,the lower the minimum miscibility temperature between flue gas and oil,which allows easier miscibility and ultimately better performance of thermal miscible flooding by air injection.The miscibility between flue gas and light oil at high temperature and high pressure is more typically characterized by phase transition at high temperature in supercritical state,and it is different from the contact extraction miscibility of CO_(2) under conventional high pressure conditions.展开更多
Deep oil and gas reservoirs are under high-temperature conditions,but traditional coring methods do not consider temperature-preserved measures and ignore the influence of temperature on rock porosity and permeability...Deep oil and gas reservoirs are under high-temperature conditions,but traditional coring methods do not consider temperature-preserved measures and ignore the influence of temperature on rock porosity and permeability,resulting in distorted resource assessments.The development of in situ temperaturepreserved coring(ITP-Coring)technology for deep reservoir rock is urgent,and thermal insulation materials are key.Therefore,hollow glass microsphere/epoxy resin thermal insulation materials(HGM/EP materials)were proposed as thermal insulation materials.The materials properties under coupled hightemperature and high-pressure(HTHP)conditions were tested.The results indicated that high pressures led to HGM destruction and that the materials water absorption significantly increased;additionally,increasing temperature accelerated the process.High temperatures directly caused the thermal conductivity of the materials to increase;additionally,the thermal conduction and convection of water caused by high pressures led to an exponential increase in the thermal conductivity.High temperatures weakened the matrix,and high pressures destroyed the HGM,which resulted in a decrease in the tensile mechanical properties of the materials.The materials entered the high elastic state at 150℃,and the mechanical properties were weakened more obviously,while the pressure led to a significant effect when the water absorption was above 10%.Meanwhile,the tensile strength/strain were 13.62 MPa/1.3%and 6.09 MPa/0.86%at 100℃ and 100 MPa,respectively,which meet the application requirements of the self-designed coring device.Finally,K46-f40 and K46-f50 HGM/EP materials were proven to be suitable for ITP-Coring under coupled conditions below 100℃ and 100 MPa.To further improve the materials properties,the interface layer and EP matrix should be optimized.The results can provide references for the optimization and engineering application of materials and thus technical support for deep oil and gas resource development.展开更多
The Pabdeh Formation represents organic matter enrichment in some oil fields,which can be considered a source rock.This study is based on the Rock–Eval,Iatroscan,and electron microscopy imaging results before and aft...The Pabdeh Formation represents organic matter enrichment in some oil fields,which can be considered a source rock.This study is based on the Rock–Eval,Iatroscan,and electron microscopy imaging results before and after heating the samples.We discovered this immature shale that undergoes burial and diagenesis,in which organic matter is converted into hydro-carbons.Primary migration is the process that transports hydrocarbons in the source rock.We investigated this phenomenon by developing a model that simulates hydrocarbon generation and fluid pressure during kerogen-to-hydrocarbon conversion.Microfractures initially formed at the tip/edge of kerogen and were filled with hydrocarbons,but as catagenesis progressed,the pressure caused by the volume increase of kerogen decreased due to hydrocarbon release.The transformation of solid kerogen into low-density bitumen/oil increased the pressure,leading to the development of damage zones in the source rock.The Pabdeh Formation’s small porethroats hindered effective expulsion,causing an increase in pore fluid pressure inside the initial microfractures.The stress accumulated due to hydrocarbon production,reaching the rock’s fracture strength,further contributed to damage zone development.During the expansion process,microfractures preferentially grew in low-strength pathways such as lithology changes,laminae boundaries,and pre-existing microfractures.When the porous pressure created by each kerogen overlapped,individual microfractures interconnected,forming a network of microfractures within the source rock.This research sheds light on the complex interplay between temperature,hydrocarbon generation,and the development of expulsion fractures in the Pabdeh Formation,providing valuable insights for understanding and optimizing hydrocarbon extraction in similar geological settings.展开更多
Here, we report the construction of magnetic core-shell microparticles for oil removal with thermal driving regeneration property. Water-in-oil-in water (W/O/W) emulsions from microfluidics are used as templates to pr...Here, we report the construction of magnetic core-shell microparticles for oil removal with thermal driving regeneration property. Water-in-oil-in water (W/O/W) emulsions from microfluidics are used as templates to prepare core-shell microparticles with magnetic holed poly (ethoxylated trimethylolpropane triacrylate) (PETPTA) shells each containing a thermal-sensitive poly (N-Isopropylacrylamide) (PNIPAM) core. The microparticles could adsorb oil from water due to the special structure and be collected with a magnetic field. Then, the oil-filled microparticles would be regenerated by thermal stimulus, in which the inner PNIPAM microgels work as thermal-sensitive pistons to force out the adsorbed oil. At the same time, the adsorbed oil would be recycled by distillation. Furthermore, the adsorption capacity of the microparticles for oil keeps very stable after 1st cycle. The adsorption and regeneration performances of the microparticles are greatly affected by the size of the holes on the outer PETPTA shells, which could be precisely controlled by regulating the interfacial forces in W/O/W emulsion templates. The optimized core-shell microparticles show excellent oil adsorption and thermal driving regeneration performances nearly without secondary pollution, and would be a reliable green adsorption material for kinds of oil.展开更多
With the increasing oil demand, the construction of oil energy reserves in China needs to be further strengthened. However, given that there has been no research on the main influencing factors of crude oil temperatur...With the increasing oil demand, the construction of oil energy reserves in China needs to be further strengthened. However, given that there has been no research on the main influencing factors of crude oil temperature drop in storage tanks under actual dynamically changing environments, this paper considers the influence of dynamic thermal environment and internal crude oil physical properties on the fluctuating changes in crude oil temperature. A theoretical model of the unsteady-state temperature drop heat transfer process is developed from a three-dimensional perspective. According to the temperature drop variation law of crude oil storage tank under the coupling effect of various heat transfer modes such as external forced convection, thermal radiation, and internal natural convection, the external dynamic thermal environment influence zone, the internal crude oil physical property influence zone, and the intermediate transition zone of the tank are proposed. And the multiple non-linear regression method is used to quantitatively characterize the influence of external ambient temperature, solar radiation, wind speed, internal crude oil density, viscosity, and specific heat capacity on the temperature drop of crude oil in each influencing zone. The results of this paper not only quantitatively explain the main influencing factors of the oil temperature drop in the top, wall, and bottom regions of the tank, but also provide a theoretical reference for oil security reserves under a dynamic thermal environment.展开更多
This paper reviews the basic research means for oilfield development and also the researches and tests of enhanced oil recovery(EOR)methods for mature oilfields and continental shale oil development,analyzes the probl...This paper reviews the basic research means for oilfield development and also the researches and tests of enhanced oil recovery(EOR)methods for mature oilfields and continental shale oil development,analyzes the problems of EOR methods,and proposes the relevant research prospects.The basic research means for oilfield development include in-situ acquisition of formation rock/fluid samples and non-destructive testing.The EOR methods for conventional and shale oil development are classified as improved water flooding(e.g.nano-water flooding),chemical flooding(e.g.low-concentration middle-phase micro-emulsion flooding),gas flooding(e.g.micro/nano bubble flooding),thermal recovery(e.g.air injection thermal-aided miscible flooding),and multi-cluster uniform fracturing/water-free fracturing,which are discussed in this paper for their mechanisms,approaches,and key technique researches and field tests.These methods have been studied with remarkable progress,and some achieved ideal results in field tests.Nonetheless,some problems still exist,such as inadequate research on mechanisms,imperfect matching technologies,and incomplete industrial chains.It is proposed to further strengthen the basic researches and expand the field tests,thereby driving the formation,promotion and application of new technologies.展开更多
Black shales are important products of material cycling and energy exchange among the lithosphere,atmosphere,hydrosphere,and biosphere.They are widely distributed throughout geological history and provide essential en...Black shales are important products of material cycling and energy exchange among the lithosphere,atmosphere,hydrosphere,and biosphere.They are widely distributed throughout geological history and provide essential energy and mineral resources for the development of human society.They also record the evolution process of the earth and improve the understanding of the earth.This review focuses on the diagenesis and formation mechanisms of black shales sedimentation,composition,evolution,and reconstruction,which have had a significant impact on the formation and enrichment of shale oil and gas.In terms of sedimentary environment,black shales can be classified into three types:Marine,terrestrial,and marine-terrestrial transitional facies.The formation processes include mechanisms such as eolian input,hypopycnal flow,gravity-driven and offshore bottom currents.From a geological perspective,the formation of black shales is often closely related to global or regional major geological events.The enrichment of organic matter is generally the result of the interaction and coupling of several factors such as primary productivity,water redox condition,and sedimentation rate.In terms of evolution,black shales have undergone diagenetic evolution of inorganic minerals,thermal evolution of organic matter and hydrocarbon generation,interactions between organic matter and inorganic minerals,and pore evolution.In terms of reconstruction,the effects of fold deformation,uplift and erosion,and fracturing have changed the stress state of black shale reservoirs,thereby having a significant impact on the pore structure.Fluid activity promotes the formation of veins,and have changed the material composition,stress structure,and reservoir properties of black shales.Regarding resource effects,the deposition of black shales is fundamental for shale oil and gas resources,the evolution of black shales promotes the shale oil and gas formation and storage,and the reconstruction of black shales would have caused the heterogeneous distribution of oil and gas in shales.Exploring the formation mechanisms and interactions of black shales at different scales is a key to in-depth research on shale formation and evolution,as well as the key to revealing the mechanism controlling shale oil and gas accumulation.The present records can reveal how these processes worked in geological history,and improve our understanding of the coupling mechanisms among regional geological events,black shales evolution,and shale oil and gas formation and enrichment.展开更多
Magnetic-liquid double suspension bearing(MLDSB)is a new type of suspension bearing based on electromagnetic suspension and supplemented by hydrostatic supporting.Without affecting the electromagnetic suspension force...Magnetic-liquid double suspension bearing(MLDSB)is a new type of suspension bearing based on electromagnetic suspension and supplemented by hydrostatic supporting.Without affecting the electromagnetic suspension force,the hydrostatic supporting effect is increased,and the real-time coupling of magnetic and liquid supporting can be realized.However,due to the high rotation speed,the rotor part produces eddy current loss,resulting in a large temperature rise and large ther-mal deformation,which makes the oil film thickness deviate from the initial design.The support and bearing characteristics are seriously affected.Therefore,this paper intends to explore the internal effects of eddy current loss of the rotor on the temperature rise and thermal deformation of MLDSB.Firstly,the 2D magnetic flow coupling mathematical model of MLDSB is established,and the eddy current loss distribution characteristics of the rotor are numerically simulated by Maxwell software.Secondly,the internal influence of mapping relationship of structural operating parameters such as input current,coil turns and rotor speed on rotor eddy current loss is revealed,and the changing trend of rotor eddy current loss under different design parameters is explored.Thirdly,the eddy cur-rent loss is loaded into the heat transfer finite element calculation model as a heat source,and the temperature rise of the rotor and its thermal deformation are simulated and analyzed,and the influ-ence of eddy current loss on rotor temperature rise and thermal deformation is revealed.Finally,the pressure-flow curve and the distribution law of the internal flow field are tested by the particle image velocimetry(PIV)system.The results show that eddy current loss increases linearly with the in-crease of coil current,coil turns and rotor speed.The effect of rotational speed on eddy current loss is much higher than that of coil current and coil turns.The maximum temperature rise,minimum temperature rise and maximum thermal deformation of the rotor increase with the increase of eddy current loss.The test results of flow-pressure and internal trace curves are basically consistent with the theoretical simulation,which effectively verifies the correctness of the theoretical simulation.The research results can provide theoretical basis for the design and safe and stable operation of magnetic fluid double suspension bearings.展开更多
The thermal degradation of two synthetic lubricants base oils, poly-a-olefins (PAO) and di-esters (DE), was investigated under oxidative pyrolysis condition and their properties were characterized in simulated "a...The thermal degradation of two synthetic lubricants base oils, poly-a-olefins (PAO) and di-esters (DE), was investigated under oxidative pyrolysis condition and their properties were characterized in simulated "areo-engine" by comparing the thermal stability and identifying the products of thermal decomposition as a function of exposure temperature. The characterization of the products were performed by means of Fourier transform infrared spectrometry (FTIR), gas chromatography/mass spectrometry (GC/MS) and viscosity experiments. The results show that PAO has the lower thermal stability, being degraded at 200℃ different from 300 ℃ for DE. Several by-products are identified during the thermal degradation of two lubricant base oils. The majority of PAO products consist of alkenes and olefins, while more oxygen-contained organic compounds are detected in DE samples based on GC/MS analysis. The related reaction mechanisms are discussed based on the experimental results.展开更多
On-site monitoring is very important for understanding formation mechanisms of frost hazards frequently occurring in pipeline foundation soils and for designing and deploying according mitigative measures in permafros...On-site monitoring is very important for understanding formation mechanisms of frost hazards frequently occurring in pipeline foundation soils and for designing and deploying according mitigative measures in permafrost regions.Significant thaw subsidence of ground surfaces along the ChinaRussia Crude Oil Pipeline(CRCOP) from Mo'he to Daqing,Heilongjiang Province,Northeast China have been observed at some segments underlain by ice-rich warm(>1.0°C) permafrost since the official operation in January 2011.Recent monitoring results of the thermal states of foundation soils at the kilometer post(KP) 304 site along the CRCOP are presented in this paper.The results indicate that during the period from 2012 to 2014,shallow soils(at the depths from0.8 to 4.0 m from ground surface) has warmed by approximately 1.0°C in the lateral range of 1.2 to 2.1 maway from the pipeline axis,and deeper permafrost(such as at the depth of 15 m,or the depth of zero annual amplitude of ground temperatures) by 0.08°C per year 4 m away from the pipe axis,and 0.07°C per year 5 m away from the pipeline axis.The results indicate an all-season talik has developed around and along the CRCOP.The thaw bulb,with a faster lateral expansion(compared with the vertical growth),enlarges in summer and shrinks in winter.This research will provide important references and bases for evaluating thermal influences of warm pipeline on permafrost and for design,construction,operation and maintenance of pipelines in permafrost regions.展开更多
Fushun oil shale(FOS) was subjected to thermal dissolution(TD) under different conditions. The results show that the optimal solvent, temperature, time, and ratio of solvent to FOS are ethanol, 300 °C, 2 h, and 5...Fushun oil shale(FOS) was subjected to thermal dissolution(TD) under different conditions. The results show that the optimal solvent, temperature, time, and ratio of solvent to FOS are ethanol, 300 °C, 2 h, and 5 ml·g^(-1),respectively and the corresponding yield of the soluble portion(SP) is 32.2%(daf), which is much higher than the oil content of FOS(ca. 6%), suggesting that TD in ethanol is an excellent way to extract organics from FOS.According to 3 direct analyses, aliphatic moieties in FOS are the most abundant followed by C\\O-containing moieties and each cluster in FOS has 3 conjugated aromatic rings on average with fewer substituents. According to the analysis with a gas chromatograph/mass spectrometer, alkanes are predominant in all the SPs. A number of alkenes were identified in the SPs from the TD, while none of the alkenes were detected in acetone-SP obtained at room temperature, implying that the TD can destroy the π-π and intertwining interactions between alkenes and macromolecular structures in FOS. Moreover, a small amount of alkyl-substituted phenols and alkoxysubstituted phenols were detected in ethanol-SP from the TD, which could be the products from ethanolyzing the macromolecular moiety of FOS.展开更多
The dry modification of aluminum hydroxide powders with phosphoric acid and the effects of modification of technological conditions on thermal stability, morphology and oil absorption of aluminum hydroxide powders wer...The dry modification of aluminum hydroxide powders with phosphoric acid and the effects of modification of technological conditions on thermal stability, morphology and oil absorption of aluminum hydroxide powders were investigated. The results show that the increase of mass ratio of phosphoric acid to aluminum hydroxide, the decrease of mass concentration of phosphoric acid and prolongation of mixing time are favorable to the improvement of thermal stability of aluminum hydroxide; when the mass ratio of phosphoric acid to aluminum hydroxide is 5:100, the mass concentration of phosphoric acid is 200 g/L and the mixing time is 10 min, the initial temperature of loss of crystal water in aluminum hydroxide rises from about 192.10 to 208.66 ℃, but the dry modification results in the appearance of agglomeration and macro-aggregate in the modified powders, and the oil absorption of modified powders becomes higher than that of original aluminum hydroxide.展开更多
Physical modeling,numerical simulation and field case analysis were carried out to find out the subsurface thermal oxidation state,thermal oxidation front characteristics and production dynamic characteristics of high...Physical modeling,numerical simulation and field case analysis were carried out to find out the subsurface thermal oxidation state,thermal oxidation front characteristics and production dynamic characteristics of high pressure air injection thermal oxidation miscible flooding technology.The lighter the composition and the lower the viscosity of the crude oil,the lower the fuel consumption and the combustion temperature are.The thermal oxidation front of light oil and volatile oil can advance stably,and a medium-temperature thermal oxidation stable displacement state can be formed in the light oil reservoir under high pressure conditions.With strong thermal gasification and distillation,light oil and volatile oil are likely to form a single phase zone of gasification and distillation with thermal flue gas at the high-temperature and high-pressure heat front,finally,an air-injection thermal miscible front.In light oil reservoirs,the development process of high-pressure air-injection thermal miscible flooding can be divided into three stages:boosting pressure stage,low gas-oil ratio and high-efficiency stable production stage and high gas-oil ratio production stage.Approximately 70%of crude oil is produced during the boosting pressure stage and low gas-oil ratio high-efficiency and stable production stage.展开更多
Lubrication failure is one of the main failure forms of gear failure.Time varying meshing stiffness is an important factor affecting the dynamic behavior of gears.However,the influence of oil film stiffness is usually...Lubrication failure is one of the main failure forms of gear failure.Time varying meshing stiffness is an important factor affecting the dynamic behavior of gears.However,the influence of oil film stiffness is usually ignored in the research process.In this paper,according to the meshing characteristics of double involute gears,based on the non-Newtonian thermal EHL theory,a new calculation method of normal and tangential oil film stiffness for double involute gears is established by the idea of subsection method.The oil film stiffness difference between double involute gears and common involute gears is analyzed,and the influence of tooth waist order parameters,working conditions,and thermal effect on the oil film stiffness are studied.The results reveal that there are some differences between normal and tangential oil film stiffness between double involute gears and common involute gears,but there is little difference.Compared with the torque,rotation speed and initial viscosity of the lubricating oil,the tooth waist order parameters have less influence on the oil film stiffness.Thermal effect has a certain influence on normal and tangential oil film stiffness,which indicates that the influence of thermal effect on the oil film can not be ignored.This research proposes a calculation method of normal and tangential oil film stiffness suitable for double involute gears,which provides a theoretical basis for improving the stability of the transmission.展开更多
Dietary oils have critical influences on human health,and thermally cooking or frying modify the components and nutritional functions of oils.Palm oil was the most widely used oil in food processing industry,but its h...Dietary oils have critical influences on human health,and thermally cooking or frying modify the components and nutritional functions of oils.Palm oil was the most widely used oil in food processing industry,but its health effects remain debatable.In the current study,we aimed to compare the effects of thermally oxidized palm oil and canola oil on gut microbiota.Palm oil or canola oil were heated at 180°C for 10 h to prepare high-fat diets.Rats were fed high-fat diets for 3 months,and hematological properties,gut microflora composition and intestinal gene expression were examined.The results indicated that heated canola oil consumption elevated plasma total cholesterol and LDL-c levels compared with unheated canola oil,but heated palm oil do not had these effects;and consumption of heated palm oil significantly elevated the relative abundance of Lactobacillucs and Roseburia in gut,compared with non-heated palm oil or two canola oil groups.Moreover,intestinal expression of IL-22 was increased in heated palm oil fed animal,though ZO-1 and GPR41 were reduced.In conclusion,heating process may enhance the effects of palm oil on proliferation of probiotics Lactobacillucs,and weaken the effects of canola oil on cholesterol transport and metabolism.展开更多
With the rapid development of Chinese petroleum industry, Oil production way of burning crude oil to produce steam need change. Heavy oil reservoir with thin layer or edgewater is unsuitable thermal recovery, electric...With the rapid development of Chinese petroleum industry, Oil production way of burning crude oil to produce steam need change. Heavy oil reservoir with thin layer or edgewater is unsuitable thermal recovery, electric heating leads to considerable electrical consumption, low injection water temperature decreases reservoir temperature and increased crude oil viscosity. The prolonged temperature difference break up reservoir pore throat cement and framework minerals. To improve high-capacity channel communication, we proposed geothermal oil recovery. Broad-sense abundant geothermal resources and existing injection water technique equipment are used, deep-seated high temperature liquid (oil-gas-water mixture) draws geothermal warming flowing layer to transit heat upward, decreases viscidity and increases fluidity. Reservoir temperature different offer geothermal fountain. Practicability process is analyzed. statistics and reservoir temperature variation analysis of Gudong Oilfield, Shengli Oilfield Company, SINOPEC, we have designed flow-chart concept for geothermal oil recovery, suggested drilling multi-branch well in heavy oil reservoir as injection-well, at the same position of geothermal fountain well, using free-pressure pump to inject hot liquid directly to aimed oil layer, made oil recovery in surrounding wells. It is proposed that geothermal oil recovery forerunner test should be first conducted in favorable blocks.展开更多
The thermal stability, particle size and morphology and oil absorption of aluminum hydroxide(ATH) treated by drymodification with three different modifiers were investigated. The experimental results show that the the...The thermal stability, particle size and morphology and oil absorption of aluminum hydroxide(ATH) treated by drymodification with three different modifiers were investigated. The experimental results show that the thermal stability of ATHpowder is markedly improved by dry modification technology with the following modifiers such as phosphoric acid, polyacrylic acidand the mixture of phosphoric acid and polyacrylic acid. The best effect comes from pure phosphoric acid, and the initial temperaturefor the loss of crystal water of ATH powder modified with pure polyacrylic acid can reach about 202 ℃ that is approximately 10 ℃higher than that of ATH powder before modification. The phenomena of agglomeration and macro-aggregate badly exist in ATHpowder modified with the modifiers containing phosphoric acid. The growth of particles and agglomerations of powders are notevident in ATH powder modified with pure polyacrylic acid. The oil absorption of ATH powder modified with the modifierscontaining phosphoric acid is apparently larger than that of original ATH powder and ATH powder modified with pure polyacrylicacid. The oil absorption of the ATH powder modified with pure polyacrylic acid is slightly smaller than that of original ATH powder.展开更多
-The temperature distributions obtained by different methods of analysis for solving thermal transfer of reinforced concrete (R. C.) submarine oil tanks (RCSOT), including flat wall method, cylinder wall method and fi...-The temperature distributions obtained by different methods of analysis for solving thermal transfer of reinforced concrete (R. C.) submarine oil tanks (RCSOT), including flat wall method, cylinder wall method and finite element method, are compared with the experimental data of thermal transfer of RCSOT. The precision and scope of applicability of different methods are discussed. The principle for selecting analysis method for solving thermal transfer of RCSOT is given. The analytical and experimental temperature distributions show that the wall of RCSOT should consist of double walls and empty space between them should be filled with sand or other heat insulation materials to reduce the temperature difference of the wall and to prevent concrete from cracking.展开更多
This paper proposed an improved temperature prediction model for oil-immersed transformer.The influences of the environmental temperature and heat-sinking capability changing with temperature were considered.When calc...This paper proposed an improved temperature prediction model for oil-immersed transformer.The influences of the environmental temperature and heat-sinking capability changing with temperature were considered.When calculating the heat dissipation from the transformer tank to surroundings,the average oil temperature was selected as the node value in the thermal circuit.The new thermal models will be validated with the delivery experimental data of three transformers: a 220 kV-300 MV.A unit,a 110 kV40 MV.A unit and a 220 kV-75 MV.A unit.Meanwhile,the results from the proposed model were also compared with two methods recommended in the IEC loading guide.展开更多
Thermal maturation in the shale oil/gas system is inherently complex due to the competitive interplays between hydrocarbon generation and retention processes.To study hydrocarbon generation characteristics from shales...Thermal maturation in the shale oil/gas system is inherently complex due to the competitive interplays between hydrocarbon generation and retention processes.To study hydrocarbon generation characteristics from shales within different stages of thermal maturation under the influence of retained oil,we performed Micro-Scale Sealed Vessels(MSSV)pyrolysis on a set of artificially matured lacustrine shale s amples from the Shahejie Formation in the Dongpu Depression in Bohai B ay Basin,China.Experimental results show that hydrocarbon yields of shale samples with or without retained oil at various thermal maturities follow different evolution paths.Heavy components(C15+)in samples crack at high temperatures and generally follow a sequence,where they first transform into C6-14 then to C2-5 and C1.Methane accounts for most of the gaseous products at high temperatures in all samples,with different origins.The cracking of C2-5 is the main methane-generating process in samples with retained oil,whereas the source of methane in samples without retained oil is kerogen.In the studied shales,retained oils at early-mature stage retard the transformation of liquid to gaseous hydrocarbon and prompt the cracking of C2-5 to C1 to some extent.TSR reaction related to gypsum in the studied samples is the primary reason that can explain the loss of hydrocarbon yields,especially at high temperatures.In addition,transformation of volatile hydrocarbons to gas and coke also accounts for the loss of generated hydrocarbon,as a secondary factor.展开更多
基金Supported by the PetroChina Science and Technology Project(2023ZG18).
文摘The miscibility of flue gas and different types of light oils is investigated through slender-tube miscible displacement experiment at high temperature and high pressure.Under the conditions of high temperature and high pressure,the miscible displacement of flue gas and light oil is possible.At the same temperature,there is a linear relationship between oil displacement efficiency and pressure.At the same pressure,the oil displacement efficiency increases gently and then rapidly to more than 90% to achieve miscible displacement with the increase of temperature.The rapid increase of oil displacement efficiency is closely related to the process that the light components of oil transit in phase state due to distillation with the rise of temperature.Moreover,at the same pressure,the lighter the oil,the lower the minimum miscibility temperature between flue gas and oil,which allows easier miscibility and ultimately better performance of thermal miscible flooding by air injection.The miscibility between flue gas and light oil at high temperature and high pressure is more typically characterized by phase transition at high temperature in supercritical state,and it is different from the contact extraction miscibility of CO_(2) under conventional high pressure conditions.
基金supported by the Sichuan Science and Technology Program (Grant Nos.2023NSFSC0004,2023NSFSC0790)the National Natural Science Foundation of China (Grant Nos.51827901,52304033)the Sichuan University Postdoctoral Fund (Grant No.2024SCU12093)。
文摘Deep oil and gas reservoirs are under high-temperature conditions,but traditional coring methods do not consider temperature-preserved measures and ignore the influence of temperature on rock porosity and permeability,resulting in distorted resource assessments.The development of in situ temperaturepreserved coring(ITP-Coring)technology for deep reservoir rock is urgent,and thermal insulation materials are key.Therefore,hollow glass microsphere/epoxy resin thermal insulation materials(HGM/EP materials)were proposed as thermal insulation materials.The materials properties under coupled hightemperature and high-pressure(HTHP)conditions were tested.The results indicated that high pressures led to HGM destruction and that the materials water absorption significantly increased;additionally,increasing temperature accelerated the process.High temperatures directly caused the thermal conductivity of the materials to increase;additionally,the thermal conduction and convection of water caused by high pressures led to an exponential increase in the thermal conductivity.High temperatures weakened the matrix,and high pressures destroyed the HGM,which resulted in a decrease in the tensile mechanical properties of the materials.The materials entered the high elastic state at 150℃,and the mechanical properties were weakened more obviously,while the pressure led to a significant effect when the water absorption was above 10%.Meanwhile,the tensile strength/strain were 13.62 MPa/1.3%and 6.09 MPa/0.86%at 100℃ and 100 MPa,respectively,which meet the application requirements of the self-designed coring device.Finally,K46-f40 and K46-f50 HGM/EP materials were proven to be suitable for ITP-Coring under coupled conditions below 100℃ and 100 MPa.To further improve the materials properties,the interface layer and EP matrix should be optimized.The results can provide references for the optimization and engineering application of materials and thus technical support for deep oil and gas resource development.
文摘The Pabdeh Formation represents organic matter enrichment in some oil fields,which can be considered a source rock.This study is based on the Rock–Eval,Iatroscan,and electron microscopy imaging results before and after heating the samples.We discovered this immature shale that undergoes burial and diagenesis,in which organic matter is converted into hydro-carbons.Primary migration is the process that transports hydrocarbons in the source rock.We investigated this phenomenon by developing a model that simulates hydrocarbon generation and fluid pressure during kerogen-to-hydrocarbon conversion.Microfractures initially formed at the tip/edge of kerogen and were filled with hydrocarbons,but as catagenesis progressed,the pressure caused by the volume increase of kerogen decreased due to hydrocarbon release.The transformation of solid kerogen into low-density bitumen/oil increased the pressure,leading to the development of damage zones in the source rock.The Pabdeh Formation’s small porethroats hindered effective expulsion,causing an increase in pore fluid pressure inside the initial microfractures.The stress accumulated due to hydrocarbon production,reaching the rock’s fracture strength,further contributed to damage zone development.During the expansion process,microfractures preferentially grew in low-strength pathways such as lithology changes,laminae boundaries,and pre-existing microfractures.When the porous pressure created by each kerogen overlapped,individual microfractures interconnected,forming a network of microfractures within the source rock.This research sheds light on the complex interplay between temperature,hydrocarbon generation,and the development of expulsion fractures in the Pabdeh Formation,providing valuable insights for understanding and optimizing hydrocarbon extraction in similar geological settings.
基金This work was supported by the National Natural Science Foundation of China[grant numbers 21706219]。
文摘Here, we report the construction of magnetic core-shell microparticles for oil removal with thermal driving regeneration property. Water-in-oil-in water (W/O/W) emulsions from microfluidics are used as templates to prepare core-shell microparticles with magnetic holed poly (ethoxylated trimethylolpropane triacrylate) (PETPTA) shells each containing a thermal-sensitive poly (N-Isopropylacrylamide) (PNIPAM) core. The microparticles could adsorb oil from water due to the special structure and be collected with a magnetic field. Then, the oil-filled microparticles would be regenerated by thermal stimulus, in which the inner PNIPAM microgels work as thermal-sensitive pistons to force out the adsorbed oil. At the same time, the adsorbed oil would be recycled by distillation. Furthermore, the adsorption capacity of the microparticles for oil keeps very stable after 1st cycle. The adsorption and regeneration performances of the microparticles are greatly affected by the size of the holes on the outer PETPTA shells, which could be precisely controlled by regulating the interfacial forces in W/O/W emulsion templates. The optimized core-shell microparticles show excellent oil adsorption and thermal driving regeneration performances nearly without secondary pollution, and would be a reliable green adsorption material for kinds of oil.
基金supported by the National Natural Science Foundation of China(52104064)(52074089)the China Postdoctoral Science Foundation(2020M681074)+3 种基金Heilongjiang Provincial Natural Science Foundation of China(YQ2023E006)University Nursing Program for Young Scholars with Creative Talents in Heilongjiang Province(UNPYSCT-2020152)Postdoctoral Science Foundation of Heilongjiang Province in China(LBH-TZ2106)(LBH-Z20122)Northeast Petroleum University Talents Introduction Fund(2019KQ18).
文摘With the increasing oil demand, the construction of oil energy reserves in China needs to be further strengthened. However, given that there has been no research on the main influencing factors of crude oil temperature drop in storage tanks under actual dynamically changing environments, this paper considers the influence of dynamic thermal environment and internal crude oil physical properties on the fluctuating changes in crude oil temperature. A theoretical model of the unsteady-state temperature drop heat transfer process is developed from a three-dimensional perspective. According to the temperature drop variation law of crude oil storage tank under the coupling effect of various heat transfer modes such as external forced convection, thermal radiation, and internal natural convection, the external dynamic thermal environment influence zone, the internal crude oil physical property influence zone, and the intermediate transition zone of the tank are proposed. And the multiple non-linear regression method is used to quantitatively characterize the influence of external ambient temperature, solar radiation, wind speed, internal crude oil density, viscosity, and specific heat capacity on the temperature drop of crude oil in each influencing zone. The results of this paper not only quantitatively explain the main influencing factors of the oil temperature drop in the top, wall, and bottom regions of the tank, but also provide a theoretical reference for oil security reserves under a dynamic thermal environment.
基金Supported by the PetroChina Science and Technology Major Project(2023ZZ04,2023ZZ08)。
文摘This paper reviews the basic research means for oilfield development and also the researches and tests of enhanced oil recovery(EOR)methods for mature oilfields and continental shale oil development,analyzes the problems of EOR methods,and proposes the relevant research prospects.The basic research means for oilfield development include in-situ acquisition of formation rock/fluid samples and non-destructive testing.The EOR methods for conventional and shale oil development are classified as improved water flooding(e.g.nano-water flooding),chemical flooding(e.g.low-concentration middle-phase micro-emulsion flooding),gas flooding(e.g.micro/nano bubble flooding),thermal recovery(e.g.air injection thermal-aided miscible flooding),and multi-cluster uniform fracturing/water-free fracturing,which are discussed in this paper for their mechanisms,approaches,and key technique researches and field tests.These methods have been studied with remarkable progress,and some achieved ideal results in field tests.Nonetheless,some problems still exist,such as inadequate research on mechanisms,imperfect matching technologies,and incomplete industrial chains.It is proposed to further strengthen the basic researches and expand the field tests,thereby driving the formation,promotion and application of new technologies.
基金supported by the projects of the China Geological Survey(DD20230043,DD20240048)the project of the National Natural Science Foundation of China(42102123)。
文摘Black shales are important products of material cycling and energy exchange among the lithosphere,atmosphere,hydrosphere,and biosphere.They are widely distributed throughout geological history and provide essential energy and mineral resources for the development of human society.They also record the evolution process of the earth and improve the understanding of the earth.This review focuses on the diagenesis and formation mechanisms of black shales sedimentation,composition,evolution,and reconstruction,which have had a significant impact on the formation and enrichment of shale oil and gas.In terms of sedimentary environment,black shales can be classified into three types:Marine,terrestrial,and marine-terrestrial transitional facies.The formation processes include mechanisms such as eolian input,hypopycnal flow,gravity-driven and offshore bottom currents.From a geological perspective,the formation of black shales is often closely related to global or regional major geological events.The enrichment of organic matter is generally the result of the interaction and coupling of several factors such as primary productivity,water redox condition,and sedimentation rate.In terms of evolution,black shales have undergone diagenetic evolution of inorganic minerals,thermal evolution of organic matter and hydrocarbon generation,interactions between organic matter and inorganic minerals,and pore evolution.In terms of reconstruction,the effects of fold deformation,uplift and erosion,and fracturing have changed the stress state of black shale reservoirs,thereby having a significant impact on the pore structure.Fluid activity promotes the formation of veins,and have changed the material composition,stress structure,and reservoir properties of black shales.Regarding resource effects,the deposition of black shales is fundamental for shale oil and gas resources,the evolution of black shales promotes the shale oil and gas formation and storage,and the reconstruction of black shales would have caused the heterogeneous distribution of oil and gas in shales.Exploring the formation mechanisms and interactions of black shales at different scales is a key to in-depth research on shale formation and evolution,as well as the key to revealing the mechanism controlling shale oil and gas accumulation.The present records can reveal how these processes worked in geological history,and improve our understanding of the coupling mechanisms among regional geological events,black shales evolution,and shale oil and gas formation and enrichment.
基金the Natural Science Foundation of Hebei Province(No.E2020203052)the S&T Program of Hebei(No.236Z1901G).
文摘Magnetic-liquid double suspension bearing(MLDSB)is a new type of suspension bearing based on electromagnetic suspension and supplemented by hydrostatic supporting.Without affecting the electromagnetic suspension force,the hydrostatic supporting effect is increased,and the real-time coupling of magnetic and liquid supporting can be realized.However,due to the high rotation speed,the rotor part produces eddy current loss,resulting in a large temperature rise and large ther-mal deformation,which makes the oil film thickness deviate from the initial design.The support and bearing characteristics are seriously affected.Therefore,this paper intends to explore the internal effects of eddy current loss of the rotor on the temperature rise and thermal deformation of MLDSB.Firstly,the 2D magnetic flow coupling mathematical model of MLDSB is established,and the eddy current loss distribution characteristics of the rotor are numerically simulated by Maxwell software.Secondly,the internal influence of mapping relationship of structural operating parameters such as input current,coil turns and rotor speed on rotor eddy current loss is revealed,and the changing trend of rotor eddy current loss under different design parameters is explored.Thirdly,the eddy cur-rent loss is loaded into the heat transfer finite element calculation model as a heat source,and the temperature rise of the rotor and its thermal deformation are simulated and analyzed,and the influ-ence of eddy current loss on rotor temperature rise and thermal deformation is revealed.Finally,the pressure-flow curve and the distribution law of the internal flow field are tested by the particle image velocimetry(PIV)system.The results show that eddy current loss increases linearly with the in-crease of coil current,coil turns and rotor speed.The effect of rotational speed on eddy current loss is much higher than that of coil current and coil turns.The maximum temperature rise,minimum temperature rise and maximum thermal deformation of the rotor increase with the increase of eddy current loss.The test results of flow-pressure and internal trace curves are basically consistent with the theoretical simulation,which effectively verifies the correctness of the theoretical simulation.The research results can provide theoretical basis for the design and safe and stable operation of magnetic fluid double suspension bearings.
基金Supported by the Fund from the Air Force Armament Department of China for Innovative Research Group(Grant KJ2012283)
文摘The thermal degradation of two synthetic lubricants base oils, poly-a-olefins (PAO) and di-esters (DE), was investigated under oxidative pyrolysis condition and their properties were characterized in simulated "areo-engine" by comparing the thermal stability and identifying the products of thermal decomposition as a function of exposure temperature. The characterization of the products were performed by means of Fourier transform infrared spectrometry (FTIR), gas chromatography/mass spectrometry (GC/MS) and viscosity experiments. The results show that PAO has the lower thermal stability, being degraded at 200℃ different from 300 ℃ for DE. Several by-products are identified during the thermal degradation of two lubricant base oils. The majority of PAO products consist of alkenes and olefins, while more oxygen-contained organic compounds are detected in DE samples based on GC/MS analysis. The related reaction mechanisms are discussed based on the experimental results.
基金supported by the National Natural Science Foundation Program of China on"Formation mechanisms and mitigative measures for thaw settlement of foundation soils of the China-Russia Crude Oil Pipeline"(Grant No.41171055)the State Key Laboratory of Frozen Soils Engineering Research Projects of China on"Monitoring on thaw settlement of permafrost around the China-Russia Crude Oil Pipeline"(Grant No.SKLFSE-ZY-11)and"Research on isotope tracing and radar detection of permafrost along the China-Russia Crude Oil Pipeline route"(Grant No.SKLFSE-201302)
文摘On-site monitoring is very important for understanding formation mechanisms of frost hazards frequently occurring in pipeline foundation soils and for designing and deploying according mitigative measures in permafrost regions.Significant thaw subsidence of ground surfaces along the ChinaRussia Crude Oil Pipeline(CRCOP) from Mo'he to Daqing,Heilongjiang Province,Northeast China have been observed at some segments underlain by ice-rich warm(>1.0°C) permafrost since the official operation in January 2011.Recent monitoring results of the thermal states of foundation soils at the kilometer post(KP) 304 site along the CRCOP are presented in this paper.The results indicate that during the period from 2012 to 2014,shallow soils(at the depths from0.8 to 4.0 m from ground surface) has warmed by approximately 1.0°C in the lateral range of 1.2 to 2.1 maway from the pipeline axis,and deeper permafrost(such as at the depth of 15 m,or the depth of zero annual amplitude of ground temperatures) by 0.08°C per year 4 m away from the pipe axis,and 0.07°C per year 5 m away from the pipeline axis.The results indicate an all-season talik has developed around and along the CRCOP.The thaw bulb,with a faster lateral expansion(compared with the vertical growth),enlarges in summer and shrinks in winter.This research will provide important references and bases for evaluating thermal influences of warm pipeline on permafrost and for design,construction,operation and maintenance of pipelines in permafrost regions.
基金Supported by the Fundamental Research Funds for the Central Universities(2017BSCXB27)the Research and the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX17_1507)
文摘Fushun oil shale(FOS) was subjected to thermal dissolution(TD) under different conditions. The results show that the optimal solvent, temperature, time, and ratio of solvent to FOS are ethanol, 300 °C, 2 h, and 5 ml·g^(-1),respectively and the corresponding yield of the soluble portion(SP) is 32.2%(daf), which is much higher than the oil content of FOS(ca. 6%), suggesting that TD in ethanol is an excellent way to extract organics from FOS.According to 3 direct analyses, aliphatic moieties in FOS are the most abundant followed by C\\O-containing moieties and each cluster in FOS has 3 conjugated aromatic rings on average with fewer substituents. According to the analysis with a gas chromatograph/mass spectrometer, alkanes are predominant in all the SPs. A number of alkenes were identified in the SPs from the TD, while none of the alkenes were detected in acetone-SP obtained at room temperature, implying that the TD can destroy the π-π and intertwining interactions between alkenes and macromolecular structures in FOS. Moreover, a small amount of alkyl-substituted phenols and alkoxysubstituted phenols were detected in ethanol-SP from the TD, which could be the products from ethanolyzing the macromolecular moiety of FOS.
基金Project(06SK2011) supported by the Science and Technology Program of Hunan Province, China
文摘The dry modification of aluminum hydroxide powders with phosphoric acid and the effects of modification of technological conditions on thermal stability, morphology and oil absorption of aluminum hydroxide powders were investigated. The results show that the increase of mass ratio of phosphoric acid to aluminum hydroxide, the decrease of mass concentration of phosphoric acid and prolongation of mixing time are favorable to the improvement of thermal stability of aluminum hydroxide; when the mass ratio of phosphoric acid to aluminum hydroxide is 5:100, the mass concentration of phosphoric acid is 200 g/L and the mixing time is 10 min, the initial temperature of loss of crystal water in aluminum hydroxide rises from about 192.10 to 208.66 ℃, but the dry modification results in the appearance of agglomeration and macro-aggregate in the modified powders, and the oil absorption of modified powders becomes higher than that of original aluminum hydroxide.
基金Supported by the Science and Technology Project of PetroChina Exploration and Production Company.
文摘Physical modeling,numerical simulation and field case analysis were carried out to find out the subsurface thermal oxidation state,thermal oxidation front characteristics and production dynamic characteristics of high pressure air injection thermal oxidation miscible flooding technology.The lighter the composition and the lower the viscosity of the crude oil,the lower the fuel consumption and the combustion temperature are.The thermal oxidation front of light oil and volatile oil can advance stably,and a medium-temperature thermal oxidation stable displacement state can be formed in the light oil reservoir under high pressure conditions.With strong thermal gasification and distillation,light oil and volatile oil are likely to form a single phase zone of gasification and distillation with thermal flue gas at the high-temperature and high-pressure heat front,finally,an air-injection thermal miscible front.In light oil reservoirs,the development process of high-pressure air-injection thermal miscible flooding can be divided into three stages:boosting pressure stage,low gas-oil ratio and high-efficiency stable production stage and high gas-oil ratio production stage.Approximately 70%of crude oil is produced during the boosting pressure stage and low gas-oil ratio high-efficiency and stable production stage.
基金Supported by National Natural Science Foundation of China(Grant No.52075279)。
文摘Lubrication failure is one of the main failure forms of gear failure.Time varying meshing stiffness is an important factor affecting the dynamic behavior of gears.However,the influence of oil film stiffness is usually ignored in the research process.In this paper,according to the meshing characteristics of double involute gears,based on the non-Newtonian thermal EHL theory,a new calculation method of normal and tangential oil film stiffness for double involute gears is established by the idea of subsection method.The oil film stiffness difference between double involute gears and common involute gears is analyzed,and the influence of tooth waist order parameters,working conditions,and thermal effect on the oil film stiffness are studied.The results reveal that there are some differences between normal and tangential oil film stiffness between double involute gears and common involute gears,but there is little difference.Compared with the torque,rotation speed and initial viscosity of the lubricating oil,the tooth waist order parameters have less influence on the oil film stiffness.Thermal effect has a certain influence on normal and tangential oil film stiffness,which indicates that the influence of thermal effect on the oil film can not be ignored.This research proposes a calculation method of normal and tangential oil film stiffness suitable for double involute gears,which provides a theoretical basis for improving the stability of the transmission.
基金Hubei Provincial Natural Science Foundation of China(Grant No.2017CFB275)National Natural Science Foundation of China(Grant Nos.31271855 and 81402669)the Fundamental Research Funds for the Wuhan Polytechnic University(2019J04).
文摘Dietary oils have critical influences on human health,and thermally cooking or frying modify the components and nutritional functions of oils.Palm oil was the most widely used oil in food processing industry,but its health effects remain debatable.In the current study,we aimed to compare the effects of thermally oxidized palm oil and canola oil on gut microbiota.Palm oil or canola oil were heated at 180°C for 10 h to prepare high-fat diets.Rats were fed high-fat diets for 3 months,and hematological properties,gut microflora composition and intestinal gene expression were examined.The results indicated that heated canola oil consumption elevated plasma total cholesterol and LDL-c levels compared with unheated canola oil,but heated palm oil do not had these effects;and consumption of heated palm oil significantly elevated the relative abundance of Lactobacillucs and Roseburia in gut,compared with non-heated palm oil or two canola oil groups.Moreover,intestinal expression of IL-22 was increased in heated palm oil fed animal,though ZO-1 and GPR41 were reduced.In conclusion,heating process may enhance the effects of palm oil on proliferation of probiotics Lactobacillucs,and weaken the effects of canola oil on cholesterol transport and metabolism.
文摘With the rapid development of Chinese petroleum industry, Oil production way of burning crude oil to produce steam need change. Heavy oil reservoir with thin layer or edgewater is unsuitable thermal recovery, electric heating leads to considerable electrical consumption, low injection water temperature decreases reservoir temperature and increased crude oil viscosity. The prolonged temperature difference break up reservoir pore throat cement and framework minerals. To improve high-capacity channel communication, we proposed geothermal oil recovery. Broad-sense abundant geothermal resources and existing injection water technique equipment are used, deep-seated high temperature liquid (oil-gas-water mixture) draws geothermal warming flowing layer to transit heat upward, decreases viscidity and increases fluidity. Reservoir temperature different offer geothermal fountain. Practicability process is analyzed. statistics and reservoir temperature variation analysis of Gudong Oilfield, Shengli Oilfield Company, SINOPEC, we have designed flow-chart concept for geothermal oil recovery, suggested drilling multi-branch well in heavy oil reservoir as injection-well, at the same position of geothermal fountain well, using free-pressure pump to inject hot liquid directly to aimed oil layer, made oil recovery in surrounding wells. It is proposed that geothermal oil recovery forerunner test should be first conducted in favorable blocks.
基金Project(06SK2011) supported by the Science and Technology Program of Hunan Province, China
文摘The thermal stability, particle size and morphology and oil absorption of aluminum hydroxide(ATH) treated by drymodification with three different modifiers were investigated. The experimental results show that the thermal stability of ATHpowder is markedly improved by dry modification technology with the following modifiers such as phosphoric acid, polyacrylic acidand the mixture of phosphoric acid and polyacrylic acid. The best effect comes from pure phosphoric acid, and the initial temperaturefor the loss of crystal water of ATH powder modified with pure polyacrylic acid can reach about 202 ℃ that is approximately 10 ℃higher than that of ATH powder before modification. The phenomena of agglomeration and macro-aggregate badly exist in ATHpowder modified with the modifiers containing phosphoric acid. The growth of particles and agglomerations of powders are notevident in ATH powder modified with pure polyacrylic acid. The oil absorption of ATH powder modified with the modifierscontaining phosphoric acid is apparently larger than that of original ATH powder and ATH powder modified with pure polyacrylicacid. The oil absorption of the ATH powder modified with pure polyacrylic acid is slightly smaller than that of original ATH powder.
文摘-The temperature distributions obtained by different methods of analysis for solving thermal transfer of reinforced concrete (R. C.) submarine oil tanks (RCSOT), including flat wall method, cylinder wall method and finite element method, are compared with the experimental data of thermal transfer of RCSOT. The precision and scope of applicability of different methods are discussed. The principle for selecting analysis method for solving thermal transfer of RCSOT is given. The analytical and experimental temperature distributions show that the wall of RCSOT should consist of double walls and empty space between them should be filled with sand or other heat insulation materials to reduce the temperature difference of the wall and to prevent concrete from cracking.
文摘This paper proposed an improved temperature prediction model for oil-immersed transformer.The influences of the environmental temperature and heat-sinking capability changing with temperature were considered.When calculating the heat dissipation from the transformer tank to surroundings,the average oil temperature was selected as the node value in the thermal circuit.The new thermal models will be validated with the delivery experimental data of three transformers: a 220 kV-300 MV.A unit,a 110 kV40 MV.A unit and a 220 kV-75 MV.A unit.Meanwhile,the results from the proposed model were also compared with two methods recommended in the IEC loading guide.
基金funded by National Natural Science Foundation of China(No.41872148)China Major Research and Development Program for Oil and Gas(No.2017ZX05049001)financial supporting from China Scholarship Council and American Association of Petroleum Geologists(Norman H.Foster Memorial Grant)。
文摘Thermal maturation in the shale oil/gas system is inherently complex due to the competitive interplays between hydrocarbon generation and retention processes.To study hydrocarbon generation characteristics from shales within different stages of thermal maturation under the influence of retained oil,we performed Micro-Scale Sealed Vessels(MSSV)pyrolysis on a set of artificially matured lacustrine shale s amples from the Shahejie Formation in the Dongpu Depression in Bohai B ay Basin,China.Experimental results show that hydrocarbon yields of shale samples with or without retained oil at various thermal maturities follow different evolution paths.Heavy components(C15+)in samples crack at high temperatures and generally follow a sequence,where they first transform into C6-14 then to C2-5 and C1.Methane accounts for most of the gaseous products at high temperatures in all samples,with different origins.The cracking of C2-5 is the main methane-generating process in samples with retained oil,whereas the source of methane in samples without retained oil is kerogen.In the studied shales,retained oils at early-mature stage retard the transformation of liquid to gaseous hydrocarbon and prompt the cracking of C2-5 to C1 to some extent.TSR reaction related to gypsum in the studied samples is the primary reason that can explain the loss of hydrocarbon yields,especially at high temperatures.In addition,transformation of volatile hydrocarbons to gas and coke also accounts for the loss of generated hydrocarbon,as a secondary factor.