Multiphase flow in porous rock is of great importance in the application of many industrial processes,including reservoir delineation,enhanced oil recovery,and CO_(2) sequestration.However,previous research typically ...Multiphase flow in porous rock is of great importance in the application of many industrial processes,including reservoir delineation,enhanced oil recovery,and CO_(2) sequestration.However,previous research typically investigated the dispersive behaviors when rock saturated with single or two-phase fluids and conducted limited studies on three-phase immiscible fluids.This study investigated the seismic dispersion,attenuation,and reflection features of seismic waves in three-phase immiscible fluidsaturated porous rocks.First,we proposed the calculation formulas of effective fluid modulus and effective fluid viscosity of multiphase immiscible fluids by taking into account the capillary pressure,reservoir wettability,and relative permeability simultaneously.Then,we analysed the frequencydependent behaviors of three-phase immiscible fluid-saturated porous rock under different fluid proportion cases using the Chapman multi-scale model.Next,the seismic responses are analysed using a four-layer model.The results indicate that the relative permeability,capillary pressure parameter,and fluid proportions are all significantly affect dispersion and attenuation.Comparative analyses demonstrate that dispersion and attenuation can be observed within the frequency range of seismic exploration for a lower capillary parameter a3 and higher oil content.Seismic responses reveal that the reflection features,such as travel time,seismic amplitude,and waveform of the bottom reflections of saturated rock and their underlying reflections are significantly dependent on fluid proportions and capillary parameters.For validation,the numerical results are further verified using the log data and real seismic data.This numerical analysis helps to further understand the wave propagation characteristics for a porous rock saturated with multiphase immiscible fluids.展开更多
As the global exploration and development of oil and gas resources advances into deep formations,the harsh conditions of high temperature and high salinity present significant challenges for drilling fluids.In order t...As the global exploration and development of oil and gas resources advances into deep formations,the harsh conditions of high temperature and high salinity present significant challenges for drilling fluids.In order to address the technical difficulties associated with the failure of filtrate loss reducers under high-temperature and high-salinity conditions.In this study,a hydrophobic zwitterionic filtrate loss reducer(PDA)was synthesized based on N,N-dimethylacrylamide(DMAA),2-acrylamido-2-methylpropane sulfonic acid(AMPS),diallyl dimethyl ammonium chloride(DMDAAC),styrene(ST)and a specialty vinyl monomer(A1).When the concentration of PDA was 3%,the FLAPI of PDA-WBDF was 9.8 mL and the FLHTHP(180℃,3.5 MPa)was 37.8 mL after aging at 240℃for 16 h.In the saturated NaCl environment,the FLAPI of PDA-SWBDF was 4.0 mL and the FLHTHP(180℃,3.5 MPa)was 32.0 mL after aging at 220℃ for 16 h.Under high-temperature and high-salinity conditions,the combined effect of anti-polyelectrolyte and hydrophobic association allowed PDA to adsorb on the bentonite surface tightly.The sulfonic acid groups of PDA increased the negative electronegativity and the hydration film thickness on bentonite surface,which enhanced the colloidal stability,maintained the flattened lamellar structure of bentonite and formed an appropriate particle size distribution,resulting in the formation of dense mud cakes and reducing the filtration loss effectively.展开更多
Smart low-solid drilling fluids(SLSDFs)with thermo-controllable rheological properties and attractive thickening characteristics have recently captivated profound attention due to their low formation damage and enhanc...Smart low-solid drilling fluids(SLSDFs)with thermo-controllable rheological properties and attractive thickening characteristics have recently captivated profound attention due to their low formation damage and enhanced cuttings lifting capacity.However,their applications to deep hole drilling at high temperatures have remained limited because of the thermal instability and environmental constraints of the thermo-associating polymers as additives.This work explored the synergistic benefits of thermo-associating polymer and biogenic nano-silica(B-SiNP)extracted from rice husk to improve the thermo-stability of SLSDF.This study shows that the nano-hybrid,TAP-S based on vinyl-terminated B-SiNP could potentially mitigate the limiting performance of conventional LSDF(F-2)caused by the failure of thermo-associating copolymers under elevated temperatures.TAP-S bearing drilling fluid(F-3)could preserve more than 5.6-fold of its initial properties(ca.apparent viscosity,plastic viscosity,yield point,and gel strength)with a nearly flat-gel profile in the temperature range of 25-230℃,which was higher than those of the counterpart F-2 and base fluid according to the results of rheological tests analysis.In addition,TAP-S exhibited an abrupt thermo-thickening characteristic with a magnitude declining by only 1.05-fold and the activation Gibbs free energy of 1339 kJ/mol above the plateau(ca.130℃),reflecting its less sensitivity compared to F-2 under a continuous heating process.As a result,a lower temperature was required to drive the dehydration of the residual fraction of lower critical solution temperature(LCST)in nano-hybrid structures than TAP according to the results of DSC analysis.Thus,lower energy was expected to disintegrate the residual hydrogen bonds formed between the LCST chains and surrounding water molecules at elevated temperatures.Moreover,TAP-S formed a solid-micro-crosslinking structure network which exhibited a more stable hydrodynamic diameter as revealed by DLS analysis.Compared with TAP,TAP-S consisted of a larger composite B-SiNP-TAP integrated spatial network structure based on the results of environmental scanning electron microscope,which conferred a degree of thermal conductivity characteristic for improved temperature resistance.This contributed to the effective binding onto bentonite particles for protection and maintained a relatively stable bentonite particle dispersion according to the results of EPM and particle size distribution analyses.Consequently,TAP-S fortified drilling fluid demonstrates improved rheological and filtration performance under severe downhole conditions.Therefore,TAP-S,the thermo-associating copolymer integrated with B-SiNP could find potential application as an eco-friendly viscosifier in LSDFs for deep-well drilling operations.展开更多
This paper concerns the Cauchy problem of 3D compressible micropolar fluids in the whole space R^(3). For regular initial data with m0E0 is suitable small, where m0 and E0 represent the upper bound of initial density ...This paper concerns the Cauchy problem of 3D compressible micropolar fluids in the whole space R^(3). For regular initial data with m0E0 is suitable small, where m0 and E0 represent the upper bound of initial density and initial energy, we prove that if ρ0 ∈ Lγ ∩ H3 with γ ∈ (1, 6), then the problem possesses a unique global classical solution on R^(3) × [0, T] with any T ∈ (0, ∞). It’s worth noting that both the vacuum states and possible random largeness of initial energy are allowed.展开更多
Addressing the critical challenges of viscosity loss and barite sag in synthetic-based drilling fluids(SBDFs)under high-temperature,high-pressure(HTHP)conditions,this study innovatively developed a hyperbranched amide...Addressing the critical challenges of viscosity loss and barite sag in synthetic-based drilling fluids(SBDFs)under high-temperature,high-pressure(HTHP)conditions,this study innovatively developed a hyperbranched amide polymer(SS-1)through a unique stepwise polycondensation strategy.By integrating dynamic ionic crosslinking for temperature-responsive rheology and rigid aromatic moieties ensuring thermal stability beyond 260℃,SS-1 achieves a molecular-level breakthrough.Performance evaluations demonstrate that adding merely 2.0 wt% SS-1 significantly enhances key properties of 210℃-aged SBDFs:plastic viscosity rises to 45 mPa⋅s,electrical stability(emulsion voltage)reaches 1426 V,and the sag factor declines to 0.509,outperforming conventional sulfonated polyacrylamide(S-PAM,0.531)by 4.3%.Mechanistic investigations reveal a trifunctional synergistic anti-sag mechanism involving electrostatic adsorption onto barite surfaces,hyperbranched steric hindrance,and colloid-stabilizing network formation.SS-1 exhibits exceptional HTHP stabilization efficacy,substantially surpassing S-PAM,thereby providing an innovative molecular design strategy and scalable solution for next-generation high-performance drilling fluid stabilizers.展开更多
Conversion and capture of carbon pollutants based on carbon dioxide to valuable green oil-field chemicals are target all over the world for controlling the global warming.The present article used new room temperature ...Conversion and capture of carbon pollutants based on carbon dioxide to valuable green oil-field chemicals are target all over the world for controlling the global warming.The present article used new room temperature amphiphilic imidazolium ionic liquids with superior surface activity in the aqueous solutions to convert carbon dioxide gas to superior amphiphilic calcium carbonate nanoparticles.In this respect,tetra-cationic ionic liquids 2-(4-dodecyldimethylamino)phenyl)-1,3-bis(3-dodecyldimethylammnonio)propyl)bromide-1-H-imidazol-3-ium acetate and 2-(4-hexyldimethylamino)phenyl)-1,3-bis(3-hexcyldimethylammnonio)propyl)bromide-1 H-imidazol-3-ium acetate were prepared.Their chemical structures,thermal as well as their carbon dioxide absorption/desorption characteristicswere evaluated.Theywere used as solvent and capping agent to synthesize calcium carbonate nanoparticles with controlled crystalline lattice,sizes,thermal properties and spherical surface morphologies.The prepared calcium carbonate nanoparticles were used as additives for the commercial water based drilling mud to improve their filter lose and rheology.The data confirm that the lower concentrations of 2-(4-dodecyldimethylamino)phenyl)-1,3-bis(3-dodecyldimethylammnonio)propyl)bromide-1-H-imidazol-3-ium acetate achieved lower seawater filter lose and improved viscosities.展开更多
Icing detection is critically important for preventing safety accidents and economic losses,especially concerning ice formation from invalidated anti-icing fluids(water and ethylene glycol)under extreme conditions.Tra...Icing detection is critically important for preventing safety accidents and economic losses,especially concerning ice formation from invalidated anti-icing fluids(water and ethylene glycol)under extreme conditions.Traditional technologies like ultrasonics and capacitor-antenna face challenges with limited detection areas,lower accuracy,and susceptibility to electromagnetic interference.Here,we introduce a novel viscosity-ultrasensitive fluorescent probe 40,4‴-(2,2-diphenyle-thene-1,1-diyl)bis-(3,5-dicarboxylate)(TPE-2B4C)based on AIEgens for moni-toring ice formation of anti-icing fluids in low-temperature environments.TPE-2B4C,consisting of four sodium carboxylate groups and multiple freely rotating benzene rings,demonstrates outstanding solubility in anti-icing fluids and exhibits no fluorescent background signal even at low temperatures(<−20°C).Upon freezing,TPE-2B4C relocates from the water phase to higher viscosity ethylene glycol,causing restriction of benzene rings and a significantly increased green fluorescence signal.TPE-2B4C can successfully determine whether the anti-icing fluids are icing from−5 to−20°C with a high contrast ratio.Due to its simple setup,fast operation,and broad applicability,our new method is anticipated to be employed for rapid,real-time,and large-scale icing detection.展开更多
With the increasing requirements for fast charging and discharging,higher requirements have been put forward for the thermal management of power batteries.Therefore,there is an urgent need to develop efficient heat tr...With the increasing requirements for fast charging and discharging,higher requirements have been put forward for the thermal management of power batteries.Therefore,there is an urgent need to develop efficient heat transfer fluids.As a new type of heat transfer fluids,functional thermal fluids mainly includ-ing nanofluids(NFs)and phase change fluids(PCFs),have the advantages of high heat carrying density,high heat transfer rate,and broad operational temperature range.However,challenges that hinder their practical applications remain.In this paper,we firstly overview the classification,thermophysical prop-erties,drawbacks,and corresponding modifications of functional thermal fluids.For NFs,the high ther-mal conductivity and high convective heat transfer performance were mainly elaborated,while the stability and viscosity issues were also analyzed.And then for PCFs,the high heat carrying density was mainly elaborated,while the problems of supercooling,stability,and viscosity were also analyzed.On this basis,the composite fluids combined NFs and PCFs technology,has been summarized.Furthermore,the thermal properties of traditional fluids,NFs,PCFs,and composite fluids are compared,which proves that functional thermal fluids are a good choice to replace traditional fluids as coolants.Then,battery thermal management system(BTMS)based on functional thermal fluids is summarized in detail,and the thermal management effects and pump consumption are compared with that of water-based BTMS.Finally,the current technical challenges that parameters optimization of functional thermal fluids and structures optimization of BTMS systematically are presented.In the future,it is necessary to pay more attention to using machine learning to predict thermophysical properties of functional thermal fluids and their applications for BTMS under actual vehicle conditions.展开更多
The Gejiu tin-copper-(tungsten)(Sn-Cu-(W))polymetallic district is located in the southwest of the W-Sn metallogenic belt in the western Youjiang Basin,Yunnan,Southwest China.Abundant W minerals have been identified i...The Gejiu tin-copper-(tungsten)(Sn-Cu-(W))polymetallic district is located in the southwest of the W-Sn metallogenic belt in the western Youjiang Basin,Yunnan,Southwest China.Abundant W minerals have been identified in the region via exploration.However,metallogenic sources and evolution of W remain unclear,and the existing metallogenic model has to be updated to guide further ore prospecting.Elemental and Sr-Nd isotopic data for scheelites assist in the determination of sources and evolution of the W-mineralizing fluids and metals in the district.Based on field geological survey,the scheelites in the Gejiu district can be categorized into three types:altered granite(Type Ⅰ),quartz vein(Type Ⅱ)from the Laochang deposit,and skarn(Type Ⅲ)from the Kafang deposit.Types Ⅰ and Ⅱ scheelites have low molybdenum(Mo)and strontium(Sr)contents,and Type Ⅱ scheelite has lower Sr contents than Type Ⅰ as well as higher Mo and Sr contents than Type Ⅲ scheelites.Varying Mo contents across the scheelite types suggests that the oxygen fugacity varied during ore accumulation.Type Ⅰ and Type Ⅱ scheelites exhibit similar rare earth elements(REE)patterns;Type Ⅲ scheelite contains lower REE content,particularly HREE,compared with the other scheelites.All scheelites exhibit negative Eu anomalies in the chondrite-normalized REE patterns.As the W-mineralization and two-mica granite share close spatial and temporal relationships,the negative Eu anomalies were likely inherited from the two-mica granite.Type Ⅰ and Type Ⅱ scheelites display varied(^(87)Sr/^(86)Sr)_(82 Ma)(0.7090-0.7141)andε_(Nd)(82 Ma)(from−9.9 to−5.4)values,similar to those of granite.However,Type Ⅲ scheelite exhibits lower(^(87)Sr/^(86)Sr)_(82 Ma)(0.7083-0.7087)and lowerε_(Nd)(82 Ma)(from−10.5 to−6.9)values than the two-mica granite.This indicates that the two-mica granite alone did not provide the ore-forming fluids and metals and that the Type Ⅲ scheelite ore-forming fluids likely involved external fluids that were probably derived from carbonate rocks.The implication is that highly differentiated two-mica granites were the source of primary W-bearing metals and fluids,which is consistent with earlier research on the origin of Sn ore-forming materials.展开更多
Millimeter channel reactors(MCRs)have received increasing attention because of their ability to enhance treatment capacity in addition to the advantages of microchannels.In previous studies,less work has been conducte...Millimeter channel reactors(MCRs)have received increasing attention because of their ability to enhance treatment capacity in addition to the advantages of microchannels.In previous studies,less work has been conducted on the micromixing process and enhancement strategies for non-Newtonian fluids in MCRs.In this study,the micromixing efficiency in MCRs was experimentally investigated using CMC(carboxymethyl cellulose sodium)aqueous solution to simulate a non-Newtonian fluid,and the enhanced mechanism of micromixing efficiency by the addition of internals and rotation was analyzed by computational fluid dynamics(CFD)simulations.The results show that in the conventional channel,increasing the flow rate improves the micromixing efficiency when the CMC concentration is low.However,when the CMC concentration is higher,the higher the flow rate,the lower the micromixing efficiency.The highest micromixing efficiency is obtained for the rotationally coupled inner components,followed by the single rotation and the lowest is for the internals only.CFD simulations reveal that the most effective way to improve the micromixing efficiency of non-Newtonian fluids with shear-thinning behavior is to increase the shear force in the reactor,which effectively reduces the apparent viscosity.These results provide the theoretical foundation for enhancing the micromixing process of non-Newtonian fluids in small-size reactors.展开更多
Drilling operations in carbonate rock heavy oil blocks(e.g.,in the Tahe Oilfield)are challenged by the intrusion of high-viscosity,temperature-sensitive formation heavy oil into the drilling fluid.This phenomenon ofte...Drilling operations in carbonate rock heavy oil blocks(e.g.,in the Tahe Oilfield)are challenged by the intrusion of high-viscosity,temperature-sensitive formation heavy oil into the drilling fluid.This phenomenon often results in wellbore blockage,reduced penetration rates,and compromised well control,thereby significantly limiting drilling efficiency and operational safety.To address this issue,this study conducts a comprehensive investigation into the mechanisms governing heavy oil invasion using a combination of laboratory experiments and field data analysis.Findings indicate that the reservoir exhibits strong heterogeneity and that the heavy oil possesses distinctive physical properties.The intrusion process is governed by multiple interrelated factors,including pressure differentials,pore structure,and the rheological behavior of the heavy oil.Experimental results reveal that the invasion of heavy oil occurs in distinct phases,with temperature playing a critical role in altering its viscosity.Specifically,as temperature increases,the apparent viscosity of the drilling fluid decreases;however,elevated pressures induce a nonlinear increase in viscosity.Furthermore,the compatibility between the drilling fluid and the intruding heavy oil declines markedly with increasing oil concentration,substantially raising the risk of wellbore obstruction.Simulation experiments further confirm that at temperatures exceeding 40℃and injection rates of L/min,the likelihood of wellbore blockage significantly≥0.4increases due to heavy oil infiltration.Based on these insights,a suite of targeted mitigation strategies is proposed.These include the formulation of specialized chemical additives,such as viscosity reducers,dispersants,and plugging removal agents,the real-time adjustment of drilling fluid density,and the implementation of advanced monitoring and early-warning systems.展开更多
The phenomenon of mud volcanism has a connection with the processes of hydrocarbon generation.However,the genesis of sediments is not often taken into consideration.The study of mud volcanoes in the West Kuban margina...The phenomenon of mud volcanism has a connection with the processes of hydrocarbon generation.However,the genesis of sediments is not often taken into consideration.The study of mud volcanoes in the West Kuban marginal marine basin and the Junggar freshwater basin revealed significant isotope-geochemical differences due to various types of sedimentation.The waters from both basins exhibit three principal geochemical facies:Na-HCO_(3),Na-Cl-HCO_(3),and Na-Cl,of which the latter type of water is the dominant.The analysis of genetic coefficients(Cl/Br,Na/Br,and B/Cl)allowed us to distinguish different pathways of mud volcanic water evolution:evaporite dissolution,formation(sedimentation)waters,and waters formed by active water-rock interaction.Through statistical research,we were able to determine that noticeable variations in the behavior of chemical elements in waters from different areas can reflect discrepancies in the geological environment and the evolutionary stage of the diagenetic water transformation.Using thermodynamic modeling,the main directions of mass transfer were shown.It was established that the waters of the Junggar Basin were at a relatively early stage of evolution and had reached equilibrium only with carbonates,while in the formation waters of the West Kuban Basin,element concentrations were also controlled by silicate minerals.The correlations betweenδ^(18)O andδ~2H values and saturation indices of halides,aluminosilicates,sulfates,and borates confirm the enrichment of water with heavy isotopes during interactions with rocks without evaporation or thermal water partition.These reactions are characterized by clay dehydration and water enrichment with^(18)O and B.The data obtained made it possible to clarify the depths of formation of mud-volcanic fluids and their possible stratigraphic sources.展开更多
Aiming at the leakage problem in the compact sandstone drilling of the Keziluoyi Formation in South-west Tarim,Nano-core-emulsion was prepared by coating modified nano-SiO_(2) with nano-emulsion,its particle size D50 ...Aiming at the leakage problem in the compact sandstone drilling of the Keziluoyi Formation in South-west Tarim,Nano-core-emulsion was prepared by coating modified nano-SiO_(2) with nano-emulsion,its particle size D50 is about 100 nm,with good dispersion stability.When 0.8%Nano-core-emulsion is added to 5%bentonite slurry,the fluid loss can be reduced by 40%,and the filter cake thickness can be reduced by 84%.Using a Nano-core-emulsion to optimize the plugging performance of potassium pol-ysulfonate drilling fluid can reduce the fluid loss of the drilling fluid by 52%,the resulting filter cake is dense and tough,and the thickness is reduced by 40%.Using the pressure conduction method to evaluate the plugging rate,the plugging rate of the drilling fluid of the Nano-core-emulsion on the core of the Keziluoyi Formation is 63.4%,which is 20.9%higher than that of the field drilling fluid.According to microscopic examination and CT scanning analysis,the material has the plugging characteristics of"inner rigid support+outer soft deformation"and has demonstrated good field application results.展开更多
The Beijing-Tianjin-Hebei Plain is among the regions in China that feature the largest scale and the fastest growth in medium and deep geothermal heating.Based on tests of 82 geothermal fluid samples from 7 geothermal...The Beijing-Tianjin-Hebei Plain is among the regions in China that feature the largest scale and the fastest growth in medium and deep geothermal heating.Based on tests of 82 geothermal fluid samples from 7 geothermal fields in Hebei Province,2 geothermal fields in Henan Province,and 2 geothermal fields in Shandong Province,and combined with previous studies on the chemical characteristics of karst geothermal water in Beijing and Tianjin,this paper systematically analyzes the migration characteristics of geothermal fluids in karst geothermal reservoirs within the Beijing-Tianjin-Hebei Plain.The hydrochemical characteristics of karst geothermal water in the research areas exhibit certain differences.The geothermal water in Hebei is more mature than that in its neighboring provinces.The distribution of total dissolved solids(TDS)and strontium elements in the area is characterized by being low in the north and south and high in the middle,suggesting that the overall flow direction of geothermal fluid is from the north and south towards the middle.Combined with the groundwater flow field and the changing trend of the hydrochemical characteristics of geothermal wells along the geological section,a geothermal water migration model has been established.The geothermal fluids originating from Taihang Mountain,Yanshan Mountain,and Western Shandong Mountain enter the basin and continue to migrate towards the central part of the basin along water-conducting faults.However,the migration characteristics of geothermal fluids with the same supply direction are not identical.The geothermal fluids from Taihang Mountain are cut off by the Niudong Fault in the north and terminate in the central uplift belt of the Jizhong Depression,while in the south,they enter the east of the Jizhong Depression relatively quickly along the Hengshui Conversion Belt.The geothermal fluids from Yanshan Mountain migrate into the basin along the Cangdong Fault,yet this fault also disrupts the hydraulic connection between the tectonic units.Considering the effective dynamic conditions,it is recommended to further expand the scale of the scientific development and utilization of geothermal energy in the geothermal water catchment areas around Xiongxian County and southwest Cangzhou City.展开更多
Jadeitites are formed either through direct precipitation from Na-Al-Si rich fluids(P-type),or by replacement of magmatic protoliths(R-type)in subduction zones.They are valuable targets for investigating the mobility ...Jadeitites are formed either through direct precipitation from Na-Al-Si rich fluids(P-type),or by replacement of magmatic protoliths(R-type)in subduction zones.They are valuable targets for investigating the mobility behavior and chemical composition of subduction zone fluids.The Rio San Juan Complex(RSJC)in the northern Dominican Republic hosts both P-and R-type jadeitites and jadeite-rich rocks,which provide ideal samples for addressing such issues.Here,we present trace element and Sr-Nd-O-Si isotope compositions of RSJC jadeitites and related rocks.Most samples show similar REE patterns,trace element distributions and δ^(18)O values to those of plagiogranite protoliths,indicating the predominance of R-type origin in RSJC.The P-type samples exhibit slightly higherδ^(30)Si values(−0.15‰to 0.25‰)than that of R-type samples(−0.20‰to 0.08‰),which place above the igneous array.The low(^(87)Sr/^(86)Sr)_(i)(0.70346 to 0.70505)and highεNd(t)values(4.6 to 6.8)of the P-type jadeitites and quartzites,along with relatively lowδ^(18)O values(4.7‰to 6.4‰)of their forming fluids,indicate that the fluids are likely derived from the altered basaltic crust rather than from oceanic sediment.However,the estimated jadeitite-and quartzite-forming fluids exhibit distinctδ^(30)Si values(0.76‰to 0.99‰and-0.48‰to-0.08‰,respectively),implying an evolution of the fluids that modified the Si isotopic compositions.Since fluid metasomatism and related desilication process could have lowered the whole-rock δ^(30)Si values,the heavy Si isotope compositions of the R-type samples are produced from the external fluids.Combing Rayleigh distillation and binary mixing simulations,we propose that fluids derived from altered oceanic crust obtained high δ^(30)Si values after crystallization of minerals enriched in light Si isotopes.The P-type jadeitites are formed through direct precipitation from this fluid.As the plagiogranite protoliths were continuously replaced by this fluid,the formed R-type samples(jadeitites and quartzites)also exhibit high δ^(30)Si values.Such rocks could significantly alter the Si isotope compositions of local mantle when they are deeply subducted at convergent plate margins.展开更多
Microbial polysaccharides,due to their unique physicochemical properties,have been shown to effec-tively enhance the stability of foam fracturing fluids.However,the combined application of microbial polysaccharides an...Microbial polysaccharides,due to their unique physicochemical properties,have been shown to effec-tively enhance the stability of foam fracturing fluids.However,the combined application of microbial polysaccharides and surfactants under high-temperature and high-salinity conditions remain poorly understood.In this study,we innovatively investigate this problem with a particular focus on foam stabilization mechanisms.By employing the Waring blender method,the optimal surfactant-microbial polysaccharide blends are identified,and the foam stability,rheological properties,and decay behavior in different systems under varying conditions are systematically analyzed for the first time.The results reveal that microbial polysaccharides significantly enhance foam stability by improving the viscoelasticity of the liquid films,particularly under high-salinity and high-temperature conditions,leading to notable improvements in both foam stability and sand-carrying capacity.Additionally,scanning electron microscopy(SEM)is used to observe the microstructure of the foam liquid films,demonstrating that the network structure formed by the foam stabilizer within the liquid film effectively inhibits foam coarsening.The Lauryl betaine and Diutan gum blend exhibits outstanding foam stability,superior sand-carrying capacity,and minimal core damage,making(LAB+MPS04)it ideal for applications in enhanced production and reservoir stimulation of unconventional reservoirs.展开更多
0 INTRODUCTION Sulfur(S)and carbon(C)are essential volatile elements in both interior and surficial systems of the Earth.The cycling of S and C in subduction zones plays a fundamental role in modulating global S-C flu...0 INTRODUCTION Sulfur(S)and carbon(C)are essential volatile elements in both interior and surficial systems of the Earth.The cycling of S and C in subduction zones plays a fundamental role in modulating global S-C fluxes and exerts a significant influence on the climate evolution,mantle's redox budget,and ore deposit formation(Bekaert et al.,2021).展开更多
Antarctica contains numerous scientific mysteries,and the Antarctic ice sheet and its underlying bedrock contain important information about the geological structure of Antarctica and the evolutionary history of the i...Antarctica contains numerous scientific mysteries,and the Antarctic ice sheet and its underlying bedrock contain important information about the geological structure of Antarctica and the evolutionary history of the ice sheet.In order to obtain the focus of these scientific explorations,the Antarctic drilling engineering is constantly developing.The drilling fluid performance directly determines the success or failure of drilling engineering.In order to enhance the poor performance for drilling fluids due to poor dispersion stability and easy settling of organoclay at ultra-low temperatures,the small-molecule wetting agent(HSR)for drilling fluid suitable for Antarctica was prepared by oleic acid,diethanolamine and benzoic acid as raw materials.Its chemical structure,properties and action mechanism were investigated by various experimental methods.The experimental results showed that 2%HSR could improve the colloidal rate for drilling fluid from 6.4%to 84.8%,and the increase rate of yield point was up to 167%.Meanwhile,it also made the drilling fluid excellent in shear dilution and thixotropy.In addition,2%HSR could increase the density from 0.872 to 0.884 g/cm^(3) at-55 ficial.And the drilling fluid with 2%HSR had a good thermal conductivity of 0.1458 W/(m·K)at-55 ficial.This study gives a new direction for the research of drilling fluid treatment agents suitable for the Antarctic region,which will provide strong support for the scientific exploration of the Antarctic region.展开更多
Wellbore instability is a critical challenge in drilling operations,especially in shale formations where interaction with water-based drilling fluids can result in significant operational risks and increased costs.To ...Wellbore instability is a critical challenge in drilling operations,especially in shale formations where interaction with water-based drilling fluids can result in significant operational risks and increased costs.To address these issues,shale chemical inhibitors have become a crucial component in drilling fluid formulations to ensure wellbore integrity.Although several researchers have published some reviews on shale inhibitors,the latest advancements in shale chemical inhibitors over the past five years still warrant further discussion and summary.This literature review provided a comprehensive examination of wellbore instability,focusing on the patterns of instability encountered in drilling and the various shale chemical inhibitors employed to mitigate these issues.The review explored the utilization of shale inhibitors in water-based drilling fluids,and the discussion highlights the timeline evolution of these inhibitors,from traditional salts and polymers to advanced ionic liquids and deep eutectic solvents.Additionally,the mechanisms of shale chemical inhibitors are summarized to guide their application.The objective of this paper is to provide a detailed review of the development of shale chemical inhibitors in water-based drilling fluids,aiming to fully appreciate shale hydration inhibition methods and to provide insights into the selection and optimization of shale inhibitors to improve wellbore stability in challengingdrilling environments.展开更多
In this study,we proposed a numerical technique for solving time-dependent partial differential equations that arise in the electro-osmotic flowofCarreau fluid across a stationary plate based on amodified exponential ...In this study,we proposed a numerical technique for solving time-dependent partial differential equations that arise in the electro-osmotic flowofCarreau fluid across a stationary plate based on amodified exponential integrator.The scheme is comprised of two explicit stages.One is the exponential integrator type stage,and the second is the Runge-Kutta type stage.The spatial-dependent terms are discretized using the compact technique.The compact scheme can achieve fourth or sixth-order spatial accuracy,while the proposed scheme attains second-order temporal accuracy.Also,a mathematical model for the electro-osmotic flow of Carreau fluid over the stationary sheet is presented with heat and mass transfer effects.The governing equations are transformed into dimensionless partial differential equations and solved by the proposed scheme.Simulation results reveal that increasing the Helmholtz-Smoluchowski velocityUHS by 400%leads to a 60%-75%rise in peak flowvelocity,while the electro-osmotic parameter me enhances near-wall acceleration.Conversely,velocity decreases significantly with higher Weissenberg numbers,indicating the Carreau fluid’s elastic resistance and increased magnetic field strength due to improved Lorentz forces.Temperature rises with the thermal conductivity parameter 2,while higher reaction ratesγdiminish concentration and local Sherwood number values.The simulation findings show the scheme’s correctness and efficacy in capturing the complicated interactions in non-Newtonian electro-osmotic transport by revealing the notable impact of electrokinetic factors on flowbehaviour.Theproposedmodel is particularly relevant for BiologicalMicro-Electro-Mechanical Systems(BioMEMS)applications,where precise control of electro-thermal transport in non-Newtonian fluids is critical for lab-on-a-chip diagnostics,drug delivery,and micro-scale thermal management.展开更多
基金supported in part by the National Natural Science Foundation of China under Grant 41874143 and Grant 42374163in part by the Key Program of Natural Science Foundation of Sichuan Province of China under Grant 2023NSFSC0019in part by the Central Funds Guiding the Local Science and Technology Development under Grant 2024ZYD0124.
文摘Multiphase flow in porous rock is of great importance in the application of many industrial processes,including reservoir delineation,enhanced oil recovery,and CO_(2) sequestration.However,previous research typically investigated the dispersive behaviors when rock saturated with single or two-phase fluids and conducted limited studies on three-phase immiscible fluids.This study investigated the seismic dispersion,attenuation,and reflection features of seismic waves in three-phase immiscible fluidsaturated porous rocks.First,we proposed the calculation formulas of effective fluid modulus and effective fluid viscosity of multiphase immiscible fluids by taking into account the capillary pressure,reservoir wettability,and relative permeability simultaneously.Then,we analysed the frequencydependent behaviors of three-phase immiscible fluid-saturated porous rock under different fluid proportion cases using the Chapman multi-scale model.Next,the seismic responses are analysed using a four-layer model.The results indicate that the relative permeability,capillary pressure parameter,and fluid proportions are all significantly affect dispersion and attenuation.Comparative analyses demonstrate that dispersion and attenuation can be observed within the frequency range of seismic exploration for a lower capillary parameter a3 and higher oil content.Seismic responses reveal that the reflection features,such as travel time,seismic amplitude,and waveform of the bottom reflections of saturated rock and their underlying reflections are significantly dependent on fluid proportions and capillary parameters.For validation,the numerical results are further verified using the log data and real seismic data.This numerical analysis helps to further understand the wave propagation characteristics for a porous rock saturated with multiphase immiscible fluids.
基金supported by State Key Laboratory of Deep Oil and Gas(No.SKLDOG2024-ZYRC-03)supported by the Excellent Young Scientists Fund of the National Natural Science Foundation of China(No.52322401)the National Natural Science Foundation of China(52288101).
文摘As the global exploration and development of oil and gas resources advances into deep formations,the harsh conditions of high temperature and high salinity present significant challenges for drilling fluids.In order to address the technical difficulties associated with the failure of filtrate loss reducers under high-temperature and high-salinity conditions.In this study,a hydrophobic zwitterionic filtrate loss reducer(PDA)was synthesized based on N,N-dimethylacrylamide(DMAA),2-acrylamido-2-methylpropane sulfonic acid(AMPS),diallyl dimethyl ammonium chloride(DMDAAC),styrene(ST)and a specialty vinyl monomer(A1).When the concentration of PDA was 3%,the FLAPI of PDA-WBDF was 9.8 mL and the FLHTHP(180℃,3.5 MPa)was 37.8 mL after aging at 240℃for 16 h.In the saturated NaCl environment,the FLAPI of PDA-SWBDF was 4.0 mL and the FLHTHP(180℃,3.5 MPa)was 32.0 mL after aging at 220℃ for 16 h.Under high-temperature and high-salinity conditions,the combined effect of anti-polyelectrolyte and hydrophobic association allowed PDA to adsorb on the bentonite surface tightly.The sulfonic acid groups of PDA increased the negative electronegativity and the hydration film thickness on bentonite surface,which enhanced the colloidal stability,maintained the flattened lamellar structure of bentonite and formed an appropriate particle size distribution,resulting in the formation of dense mud cakes and reducing the filtration loss effectively.
基金supported by the National Natural Science Foundation for International Young Scientists of China(Grant No.52150410427)funding of Scientific Research Startup Project for High-Level Talents of Shandong Institute of Petroleum and Chemical Technology(Grant No.DJB2023020 and Grant No.2023SS019).
文摘Smart low-solid drilling fluids(SLSDFs)with thermo-controllable rheological properties and attractive thickening characteristics have recently captivated profound attention due to their low formation damage and enhanced cuttings lifting capacity.However,their applications to deep hole drilling at high temperatures have remained limited because of the thermal instability and environmental constraints of the thermo-associating polymers as additives.This work explored the synergistic benefits of thermo-associating polymer and biogenic nano-silica(B-SiNP)extracted from rice husk to improve the thermo-stability of SLSDF.This study shows that the nano-hybrid,TAP-S based on vinyl-terminated B-SiNP could potentially mitigate the limiting performance of conventional LSDF(F-2)caused by the failure of thermo-associating copolymers under elevated temperatures.TAP-S bearing drilling fluid(F-3)could preserve more than 5.6-fold of its initial properties(ca.apparent viscosity,plastic viscosity,yield point,and gel strength)with a nearly flat-gel profile in the temperature range of 25-230℃,which was higher than those of the counterpart F-2 and base fluid according to the results of rheological tests analysis.In addition,TAP-S exhibited an abrupt thermo-thickening characteristic with a magnitude declining by only 1.05-fold and the activation Gibbs free energy of 1339 kJ/mol above the plateau(ca.130℃),reflecting its less sensitivity compared to F-2 under a continuous heating process.As a result,a lower temperature was required to drive the dehydration of the residual fraction of lower critical solution temperature(LCST)in nano-hybrid structures than TAP according to the results of DSC analysis.Thus,lower energy was expected to disintegrate the residual hydrogen bonds formed between the LCST chains and surrounding water molecules at elevated temperatures.Moreover,TAP-S formed a solid-micro-crosslinking structure network which exhibited a more stable hydrodynamic diameter as revealed by DLS analysis.Compared with TAP,TAP-S consisted of a larger composite B-SiNP-TAP integrated spatial network structure based on the results of environmental scanning electron microscope,which conferred a degree of thermal conductivity characteristic for improved temperature resistance.This contributed to the effective binding onto bentonite particles for protection and maintained a relatively stable bentonite particle dispersion according to the results of EPM and particle size distribution analyses.Consequently,TAP-S fortified drilling fluid demonstrates improved rheological and filtration performance under severe downhole conditions.Therefore,TAP-S,the thermo-associating copolymer integrated with B-SiNP could find potential application as an eco-friendly viscosifier in LSDFs for deep-well drilling operations.
基金supported by the Natural Science Foundation of Shandong Province of China(ZR2024MA033ZR2021QA049).
文摘This paper concerns the Cauchy problem of 3D compressible micropolar fluids in the whole space R^(3). For regular initial data with m0E0 is suitable small, where m0 and E0 represent the upper bound of initial density and initial energy, we prove that if ρ0 ∈ Lγ ∩ H3 with γ ∈ (1, 6), then the problem possesses a unique global classical solution on R^(3) × [0, T] with any T ∈ (0, ∞). It’s worth noting that both the vacuum states and possible random largeness of initial energy are allowed.
基金supported by Science,Technology&Innovation Funding Authority(STDF)under grant(No.47062).
文摘Conversion and capture of carbon pollutants based on carbon dioxide to valuable green oil-field chemicals are target all over the world for controlling the global warming.The present article used new room temperature amphiphilic imidazolium ionic liquids with superior surface activity in the aqueous solutions to convert carbon dioxide gas to superior amphiphilic calcium carbonate nanoparticles.In this respect,tetra-cationic ionic liquids 2-(4-dodecyldimethylamino)phenyl)-1,3-bis(3-dodecyldimethylammnonio)propyl)bromide-1-H-imidazol-3-ium acetate and 2-(4-hexyldimethylamino)phenyl)-1,3-bis(3-hexcyldimethylammnonio)propyl)bromide-1 H-imidazol-3-ium acetate were prepared.Their chemical structures,thermal as well as their carbon dioxide absorption/desorption characteristicswere evaluated.Theywere used as solvent and capping agent to synthesize calcium carbonate nanoparticles with controlled crystalline lattice,sizes,thermal properties and spherical surface morphologies.The prepared calcium carbonate nanoparticles were used as additives for the commercial water based drilling mud to improve their filter lose and rheology.The data confirm that the lower concentrations of 2-(4-dodecyldimethylamino)phenyl)-1,3-bis(3-dodecyldimethylammnonio)propyl)bromide-1-H-imidazol-3-ium acetate achieved lower seawater filter lose and improved viscosities.
基金support from the National Natural Science Foundation of China(9235630033,22105069)Shanghai Pujiang Program(20PJ1402900)+2 种基金Shanghai Natural Science Foundation(21ZR1418400)Innovation Program of Shanghai Municipal Education Commission(2023FGS01)Natural Science Foundation of Jiangsu Province(BK20231225).
文摘Icing detection is critically important for preventing safety accidents and economic losses,especially concerning ice formation from invalidated anti-icing fluids(water and ethylene glycol)under extreme conditions.Traditional technologies like ultrasonics and capacitor-antenna face challenges with limited detection areas,lower accuracy,and susceptibility to electromagnetic interference.Here,we introduce a novel viscosity-ultrasensitive fluorescent probe 40,4‴-(2,2-diphenyle-thene-1,1-diyl)bis-(3,5-dicarboxylate)(TPE-2B4C)based on AIEgens for moni-toring ice formation of anti-icing fluids in low-temperature environments.TPE-2B4C,consisting of four sodium carboxylate groups and multiple freely rotating benzene rings,demonstrates outstanding solubility in anti-icing fluids and exhibits no fluorescent background signal even at low temperatures(<−20°C).Upon freezing,TPE-2B4C relocates from the water phase to higher viscosity ethylene glycol,causing restriction of benzene rings and a significantly increased green fluorescence signal.TPE-2B4C can successfully determine whether the anti-icing fluids are icing from−5 to−20°C with a high contrast ratio.Due to its simple setup,fast operation,and broad applicability,our new method is anticipated to be employed for rapid,real-time,and large-scale icing detection.
基金supported by the National Natural Science Foundation of China(Grant No.52271320)"Mechanics+"interdisciplinary innovation youth fund project of Ningbo University(LJ2023005).
文摘With the increasing requirements for fast charging and discharging,higher requirements have been put forward for the thermal management of power batteries.Therefore,there is an urgent need to develop efficient heat transfer fluids.As a new type of heat transfer fluids,functional thermal fluids mainly includ-ing nanofluids(NFs)and phase change fluids(PCFs),have the advantages of high heat carrying density,high heat transfer rate,and broad operational temperature range.However,challenges that hinder their practical applications remain.In this paper,we firstly overview the classification,thermophysical prop-erties,drawbacks,and corresponding modifications of functional thermal fluids.For NFs,the high ther-mal conductivity and high convective heat transfer performance were mainly elaborated,while the stability and viscosity issues were also analyzed.And then for PCFs,the high heat carrying density was mainly elaborated,while the problems of supercooling,stability,and viscosity were also analyzed.On this basis,the composite fluids combined NFs and PCFs technology,has been summarized.Furthermore,the thermal properties of traditional fluids,NFs,PCFs,and composite fluids are compared,which proves that functional thermal fluids are a good choice to replace traditional fluids as coolants.Then,battery thermal management system(BTMS)based on functional thermal fluids is summarized in detail,and the thermal management effects and pump consumption are compared with that of water-based BTMS.Finally,the current technical challenges that parameters optimization of functional thermal fluids and structures optimization of BTMS systematically are presented.In the future,it is necessary to pay more attention to using machine learning to predict thermophysical properties of functional thermal fluids and their applications for BTMS under actual vehicle conditions.
基金financed by Yunnan Major Scientific and Technological Projects(Grant No.202202AG050006)the National Natural Science Foundation of China(Grant No.42462011)Projects of Yunnan Province Technology Hall(Grant No.202305AT350004).
文摘The Gejiu tin-copper-(tungsten)(Sn-Cu-(W))polymetallic district is located in the southwest of the W-Sn metallogenic belt in the western Youjiang Basin,Yunnan,Southwest China.Abundant W minerals have been identified in the region via exploration.However,metallogenic sources and evolution of W remain unclear,and the existing metallogenic model has to be updated to guide further ore prospecting.Elemental and Sr-Nd isotopic data for scheelites assist in the determination of sources and evolution of the W-mineralizing fluids and metals in the district.Based on field geological survey,the scheelites in the Gejiu district can be categorized into three types:altered granite(Type Ⅰ),quartz vein(Type Ⅱ)from the Laochang deposit,and skarn(Type Ⅲ)from the Kafang deposit.Types Ⅰ and Ⅱ scheelites have low molybdenum(Mo)and strontium(Sr)contents,and Type Ⅱ scheelite has lower Sr contents than Type Ⅰ as well as higher Mo and Sr contents than Type Ⅲ scheelites.Varying Mo contents across the scheelite types suggests that the oxygen fugacity varied during ore accumulation.Type Ⅰ and Type Ⅱ scheelites exhibit similar rare earth elements(REE)patterns;Type Ⅲ scheelite contains lower REE content,particularly HREE,compared with the other scheelites.All scheelites exhibit negative Eu anomalies in the chondrite-normalized REE patterns.As the W-mineralization and two-mica granite share close spatial and temporal relationships,the negative Eu anomalies were likely inherited from the two-mica granite.Type Ⅰ and Type Ⅱ scheelites display varied(^(87)Sr/^(86)Sr)_(82 Ma)(0.7090-0.7141)andε_(Nd)(82 Ma)(from−9.9 to−5.4)values,similar to those of granite.However,Type Ⅲ scheelite exhibits lower(^(87)Sr/^(86)Sr)_(82 Ma)(0.7083-0.7087)and lowerε_(Nd)(82 Ma)(from−10.5 to−6.9)values than the two-mica granite.This indicates that the two-mica granite alone did not provide the ore-forming fluids and metals and that the Type Ⅲ scheelite ore-forming fluids likely involved external fluids that were probably derived from carbonate rocks.The implication is that highly differentiated two-mica granites were the source of primary W-bearing metals and fluids,which is consistent with earlier research on the origin of Sn ore-forming materials.
基金supported by the National Natural Science Foundation of China(22078009)National Key Research Program of China(2021YFC3001102,2021YFC3001100).
文摘Millimeter channel reactors(MCRs)have received increasing attention because of their ability to enhance treatment capacity in addition to the advantages of microchannels.In previous studies,less work has been conducted on the micromixing process and enhancement strategies for non-Newtonian fluids in MCRs.In this study,the micromixing efficiency in MCRs was experimentally investigated using CMC(carboxymethyl cellulose sodium)aqueous solution to simulate a non-Newtonian fluid,and the enhanced mechanism of micromixing efficiency by the addition of internals and rotation was analyzed by computational fluid dynamics(CFD)simulations.The results show that in the conventional channel,increasing the flow rate improves the micromixing efficiency when the CMC concentration is low.However,when the CMC concentration is higher,the higher the flow rate,the lower the micromixing efficiency.The highest micromixing efficiency is obtained for the rotationally coupled inner components,followed by the single rotation and the lowest is for the internals only.CFD simulations reveal that the most effective way to improve the micromixing efficiency of non-Newtonian fluids with shear-thinning behavior is to increase the shear force in the reactor,which effectively reduces the apparent viscosity.These results provide the theoretical foundation for enhancing the micromixing process of non-Newtonian fluids in small-size reactors.
基金Hubei Key Laboratory of Oil and Gas Drilling and Production Engineering(Yangtze University),China(Grant No.YQZC202415)Hubei Province Science and Technology Plan Project(Key R&D Special Project),China(Grant No.2023BCB070)+2 种基金Key R&D Program Project in Xinjiang,China,Grant No.2022B01042Guiding Project of Scientific Research Program of Education Department of Hubei Province,China(Grant No.B2023024)Open Fund of National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation(Southwest Petroleum University),Grant No.PLN2023-03.
文摘Drilling operations in carbonate rock heavy oil blocks(e.g.,in the Tahe Oilfield)are challenged by the intrusion of high-viscosity,temperature-sensitive formation heavy oil into the drilling fluid.This phenomenon often results in wellbore blockage,reduced penetration rates,and compromised well control,thereby significantly limiting drilling efficiency and operational safety.To address this issue,this study conducts a comprehensive investigation into the mechanisms governing heavy oil invasion using a combination of laboratory experiments and field data analysis.Findings indicate that the reservoir exhibits strong heterogeneity and that the heavy oil possesses distinctive physical properties.The intrusion process is governed by multiple interrelated factors,including pressure differentials,pore structure,and the rheological behavior of the heavy oil.Experimental results reveal that the invasion of heavy oil occurs in distinct phases,with temperature playing a critical role in altering its viscosity.Specifically,as temperature increases,the apparent viscosity of the drilling fluid decreases;however,elevated pressures induce a nonlinear increase in viscosity.Furthermore,the compatibility between the drilling fluid and the intruding heavy oil declines markedly with increasing oil concentration,substantially raising the risk of wellbore obstruction.Simulation experiments further confirm that at temperatures exceeding 40℃and injection rates of L/min,the likelihood of wellbore blockage significantly≥0.4increases due to heavy oil infiltration.Based on these insights,a suite of targeted mitigation strategies is proposed.These include the formulation of specialized chemical additives,such as viscosity reducers,dispersants,and plugging removal agents,the real-time adjustment of drilling fluid density,and the implementation of advanced monitoring and early-warning systems.
基金partly supported by the NSFC-RSF Joint Research project(Nos.42261134534,23-47-00035)funded by the Chinese Academy of Sciences President’s International Fellowship Initiative(Nos.2024VCA0006,2024VCB0013)the National Natural Science Foundation of China(No.42442006)。
文摘The phenomenon of mud volcanism has a connection with the processes of hydrocarbon generation.However,the genesis of sediments is not often taken into consideration.The study of mud volcanoes in the West Kuban marginal marine basin and the Junggar freshwater basin revealed significant isotope-geochemical differences due to various types of sedimentation.The waters from both basins exhibit three principal geochemical facies:Na-HCO_(3),Na-Cl-HCO_(3),and Na-Cl,of which the latter type of water is the dominant.The analysis of genetic coefficients(Cl/Br,Na/Br,and B/Cl)allowed us to distinguish different pathways of mud volcanic water evolution:evaporite dissolution,formation(sedimentation)waters,and waters formed by active water-rock interaction.Through statistical research,we were able to determine that noticeable variations in the behavior of chemical elements in waters from different areas can reflect discrepancies in the geological environment and the evolutionary stage of the diagenetic water transformation.Using thermodynamic modeling,the main directions of mass transfer were shown.It was established that the waters of the Junggar Basin were at a relatively early stage of evolution and had reached equilibrium only with carbonates,while in the formation waters of the West Kuban Basin,element concentrations were also controlled by silicate minerals.The correlations betweenδ^(18)O andδ~2H values and saturation indices of halides,aluminosilicates,sulfates,and borates confirm the enrichment of water with heavy isotopes during interactions with rocks without evaporation or thermal water partition.These reactions are characterized by clay dehydration and water enrichment with^(18)O and B.The data obtained made it possible to clarify the depths of formation of mud-volcanic fluids and their possible stratigraphic sources.
基金supported by Tarim Oilfield Project“Study on Formation Characteristics and Technical Countermeasures of Drilling Fluid in Yingsha and Yulong Blocks”(Project No.201019121044)the National Natural Science Foundation of China(ZX20200280).
文摘Aiming at the leakage problem in the compact sandstone drilling of the Keziluoyi Formation in South-west Tarim,Nano-core-emulsion was prepared by coating modified nano-SiO_(2) with nano-emulsion,its particle size D50 is about 100 nm,with good dispersion stability.When 0.8%Nano-core-emulsion is added to 5%bentonite slurry,the fluid loss can be reduced by 40%,and the filter cake thickness can be reduced by 84%.Using a Nano-core-emulsion to optimize the plugging performance of potassium pol-ysulfonate drilling fluid can reduce the fluid loss of the drilling fluid by 52%,the resulting filter cake is dense and tough,and the thickness is reduced by 40%.Using the pressure conduction method to evaluate the plugging rate,the plugging rate of the drilling fluid of the Nano-core-emulsion on the core of the Keziluoyi Formation is 63.4%,which is 20.9%higher than that of the field drilling fluid.According to microscopic examination and CT scanning analysis,the material has the plugging characteristics of"inner rigid support+outer soft deformation"and has demonstrated good field application results.
基金support received from the National Major Special Project titled“Exploration and Evaluation of Deep Geothermal Energy in Key Regions”(Project No.2024ZD1003600)the Science and Technology Department of Sinopec(Project No.JP24071).
文摘The Beijing-Tianjin-Hebei Plain is among the regions in China that feature the largest scale and the fastest growth in medium and deep geothermal heating.Based on tests of 82 geothermal fluid samples from 7 geothermal fields in Hebei Province,2 geothermal fields in Henan Province,and 2 geothermal fields in Shandong Province,and combined with previous studies on the chemical characteristics of karst geothermal water in Beijing and Tianjin,this paper systematically analyzes the migration characteristics of geothermal fluids in karst geothermal reservoirs within the Beijing-Tianjin-Hebei Plain.The hydrochemical characteristics of karst geothermal water in the research areas exhibit certain differences.The geothermal water in Hebei is more mature than that in its neighboring provinces.The distribution of total dissolved solids(TDS)and strontium elements in the area is characterized by being low in the north and south and high in the middle,suggesting that the overall flow direction of geothermal fluid is from the north and south towards the middle.Combined with the groundwater flow field and the changing trend of the hydrochemical characteristics of geothermal wells along the geological section,a geothermal water migration model has been established.The geothermal fluids originating from Taihang Mountain,Yanshan Mountain,and Western Shandong Mountain enter the basin and continue to migrate towards the central part of the basin along water-conducting faults.However,the migration characteristics of geothermal fluids with the same supply direction are not identical.The geothermal fluids from Taihang Mountain are cut off by the Niudong Fault in the north and terminate in the central uplift belt of the Jizhong Depression,while in the south,they enter the east of the Jizhong Depression relatively quickly along the Hengshui Conversion Belt.The geothermal fluids from Yanshan Mountain migrate into the basin along the Cangdong Fault,yet this fault also disrupts the hydraulic connection between the tectonic units.Considering the effective dynamic conditions,it is recommended to further expand the scale of the scientific development and utilization of geothermal energy in the geothermal water catchment areas around Xiongxian County and southwest Cangzhou City.
基金supported by funds from the National Key Research and Development Program of China(Grant No.2024YFF0807302)National Natural Science Foundation of China(42273043,42173003)the International Visiting Professorship of USTC(2024BVR23).
文摘Jadeitites are formed either through direct precipitation from Na-Al-Si rich fluids(P-type),or by replacement of magmatic protoliths(R-type)in subduction zones.They are valuable targets for investigating the mobility behavior and chemical composition of subduction zone fluids.The Rio San Juan Complex(RSJC)in the northern Dominican Republic hosts both P-and R-type jadeitites and jadeite-rich rocks,which provide ideal samples for addressing such issues.Here,we present trace element and Sr-Nd-O-Si isotope compositions of RSJC jadeitites and related rocks.Most samples show similar REE patterns,trace element distributions and δ^(18)O values to those of plagiogranite protoliths,indicating the predominance of R-type origin in RSJC.The P-type samples exhibit slightly higherδ^(30)Si values(−0.15‰to 0.25‰)than that of R-type samples(−0.20‰to 0.08‰),which place above the igneous array.The low(^(87)Sr/^(86)Sr)_(i)(0.70346 to 0.70505)and highεNd(t)values(4.6 to 6.8)of the P-type jadeitites and quartzites,along with relatively lowδ^(18)O values(4.7‰to 6.4‰)of their forming fluids,indicate that the fluids are likely derived from the altered basaltic crust rather than from oceanic sediment.However,the estimated jadeitite-and quartzite-forming fluids exhibit distinctδ^(30)Si values(0.76‰to 0.99‰and-0.48‰to-0.08‰,respectively),implying an evolution of the fluids that modified the Si isotopic compositions.Since fluid metasomatism and related desilication process could have lowered the whole-rock δ^(30)Si values,the heavy Si isotope compositions of the R-type samples are produced from the external fluids.Combing Rayleigh distillation and binary mixing simulations,we propose that fluids derived from altered oceanic crust obtained high δ^(30)Si values after crystallization of minerals enriched in light Si isotopes.The P-type jadeitites are formed through direct precipitation from this fluid.As the plagiogranite protoliths were continuously replaced by this fluid,the formed R-type samples(jadeitites and quartzites)also exhibit high δ^(30)Si values.Such rocks could significantly alter the Si isotope compositions of local mantle when they are deeply subducted at convergent plate margins.
基金supported by the Key Technology Research on Increasing Recovery Rate in Tight Sandstone Gas Reservoirs,a Major Scientific and Technological Special Project of China National Petroleum Corporation(Project No.2023ZZ25).
文摘Microbial polysaccharides,due to their unique physicochemical properties,have been shown to effec-tively enhance the stability of foam fracturing fluids.However,the combined application of microbial polysaccharides and surfactants under high-temperature and high-salinity conditions remain poorly understood.In this study,we innovatively investigate this problem with a particular focus on foam stabilization mechanisms.By employing the Waring blender method,the optimal surfactant-microbial polysaccharide blends are identified,and the foam stability,rheological properties,and decay behavior in different systems under varying conditions are systematically analyzed for the first time.The results reveal that microbial polysaccharides significantly enhance foam stability by improving the viscoelasticity of the liquid films,particularly under high-salinity and high-temperature conditions,leading to notable improvements in both foam stability and sand-carrying capacity.Additionally,scanning electron microscopy(SEM)is used to observe the microstructure of the foam liquid films,demonstrating that the network structure formed by the foam stabilizer within the liquid film effectively inhibits foam coarsening.The Lauryl betaine and Diutan gum blend exhibits outstanding foam stability,superior sand-carrying capacity,and minimal core damage,making(LAB+MPS04)it ideal for applications in enhanced production and reservoir stimulation of unconventional reservoirs.
基金financially supported by the National Natural Science Foundation of China(Nos.92355301,42302061)the China Postdoctoral Science Foundation(No.2023M743471)+1 种基金the Key Research Program of the Institute of Geology and Geophysics,Chinese Academy of Sciences(No.IGGCAS-202204)the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.Y2021026)。
文摘0 INTRODUCTION Sulfur(S)and carbon(C)are essential volatile elements in both interior and surficial systems of the Earth.The cycling of S and C in subduction zones plays a fundamental role in modulating global S-C fluxes and exerts a significant influence on the climate evolution,mantle's redox budget,and ore deposit formation(Bekaert et al.,2021).
基金financially supported by the National Natural Science Foundation of China(No.52274021)the National Key Research and Development Program of China(No.2021YFA0719102)。
文摘Antarctica contains numerous scientific mysteries,and the Antarctic ice sheet and its underlying bedrock contain important information about the geological structure of Antarctica and the evolutionary history of the ice sheet.In order to obtain the focus of these scientific explorations,the Antarctic drilling engineering is constantly developing.The drilling fluid performance directly determines the success or failure of drilling engineering.In order to enhance the poor performance for drilling fluids due to poor dispersion stability and easy settling of organoclay at ultra-low temperatures,the small-molecule wetting agent(HSR)for drilling fluid suitable for Antarctica was prepared by oleic acid,diethanolamine and benzoic acid as raw materials.Its chemical structure,properties and action mechanism were investigated by various experimental methods.The experimental results showed that 2%HSR could improve the colloidal rate for drilling fluid from 6.4%to 84.8%,and the increase rate of yield point was up to 167%.Meanwhile,it also made the drilling fluid excellent in shear dilution and thixotropy.In addition,2%HSR could increase the density from 0.872 to 0.884 g/cm^(3) at-55 ficial.And the drilling fluid with 2%HSR had a good thermal conductivity of 0.1458 W/(m·K)at-55 ficial.This study gives a new direction for the research of drilling fluid treatment agents suitable for the Antarctic region,which will provide strong support for the scientific exploration of the Antarctic region.
基金supported by the Research Foundation of China University of Petroleum-Beijing at Karamay(No.XQZX20250032)the Natural Science Foundation of Xinjiang Uygur Autonomous Region(No.2022D01A250)the Basic Research Foundation of Xinjiang Uygur Autonomous Region(No.XQZX20250003)。
文摘Wellbore instability is a critical challenge in drilling operations,especially in shale formations where interaction with water-based drilling fluids can result in significant operational risks and increased costs.To address these issues,shale chemical inhibitors have become a crucial component in drilling fluid formulations to ensure wellbore integrity.Although several researchers have published some reviews on shale inhibitors,the latest advancements in shale chemical inhibitors over the past five years still warrant further discussion and summary.This literature review provided a comprehensive examination of wellbore instability,focusing on the patterns of instability encountered in drilling and the various shale chemical inhibitors employed to mitigate these issues.The review explored the utilization of shale inhibitors in water-based drilling fluids,and the discussion highlights the timeline evolution of these inhibitors,from traditional salts and polymers to advanced ionic liquids and deep eutectic solvents.Additionally,the mechanisms of shale chemical inhibitors are summarized to guide their application.The objective of this paper is to provide a detailed review of the development of shale chemical inhibitors in water-based drilling fluids,aiming to fully appreciate shale hydration inhibition methods and to provide insights into the selection and optimization of shale inhibitors to improve wellbore stability in challengingdrilling environments.
基金supported and funded by the Deanship of Scientific Research at Imam Mohammad Ibn Saud Islamic University(IMSIU)(grant number IMSIU-DDRSP2503).
文摘In this study,we proposed a numerical technique for solving time-dependent partial differential equations that arise in the electro-osmotic flowofCarreau fluid across a stationary plate based on amodified exponential integrator.The scheme is comprised of two explicit stages.One is the exponential integrator type stage,and the second is the Runge-Kutta type stage.The spatial-dependent terms are discretized using the compact technique.The compact scheme can achieve fourth or sixth-order spatial accuracy,while the proposed scheme attains second-order temporal accuracy.Also,a mathematical model for the electro-osmotic flow of Carreau fluid over the stationary sheet is presented with heat and mass transfer effects.The governing equations are transformed into dimensionless partial differential equations and solved by the proposed scheme.Simulation results reveal that increasing the Helmholtz-Smoluchowski velocityUHS by 400%leads to a 60%-75%rise in peak flowvelocity,while the electro-osmotic parameter me enhances near-wall acceleration.Conversely,velocity decreases significantly with higher Weissenberg numbers,indicating the Carreau fluid’s elastic resistance and increased magnetic field strength due to improved Lorentz forces.Temperature rises with the thermal conductivity parameter 2,while higher reaction ratesγdiminish concentration and local Sherwood number values.The simulation findings show the scheme’s correctness and efficacy in capturing the complicated interactions in non-Newtonian electro-osmotic transport by revealing the notable impact of electrokinetic factors on flowbehaviour.Theproposedmodel is particularly relevant for BiologicalMicro-Electro-Mechanical Systems(BioMEMS)applications,where precise control of electro-thermal transport in non-Newtonian fluids is critical for lab-on-a-chip diagnostics,drug delivery,and micro-scale thermal management.
