During oil displacement,surfactants often encounter challenges such as emulsion instability and channeling,which can compromise their efficiency.To address these issues,polymer microspheres were synthesized via revers...During oil displacement,surfactants often encounter challenges such as emulsion instability and channeling,which can compromise their efficiency.To address these issues,polymer microspheres were synthesized via reverse microemulsion polymerization using acrylamide,2-methyl-2-acrylamidopropane sulfonic acid,and stearyl methacrylate as monomers,with N,N-methylenebisacrylamide as the crosslinker.The microspheres were then combined with sodium alkyl alcohol polyoxyethylene ether carboxylate to enhance emulsion stability and expand the swept volume of surfactant.A stable reverse microemulsion system was prepared using the maximum water solubilization rate as the indicator,and microspheres were synthesized based on this system.The ability of the microspheres to enhance emulsion stability was systematically evaluated.The plugging performance and enhanced oil recovery(EOR)efficiency of the microsphere/surfactant composite system were assessed through core seepage and oil displacement experiments.The experimental results demonstrated that microspheres were successfully prepared in a water-in-oil reverse microemulsion system with a solubilization rate of 42%.The emulsion stability was evaluated under an oil-to-water ratio of 7:3,a temperature of 80℃,and a salinity of 44,592 mg/L,by manually shaking the test tube five times.It was observed that the complete phase separation time of the emulsion increased from 10 to 120 min after the addition of microspheres.Under different permeability conditions(100×10^(-3),300×10^(-3),500×10^(-3)μm^(2)),the recovery efficiency of the composite system increased by 4.5%,8.3%,and 4.8%,respectively,compared to a single surfactant system.The microspheres developed in this study enhanced emulsion stability and increased the swept volume of surfactant within the formation,significantly boosting its oil recovery efficiency.展开更多
The stability of acid-crude oil emulsion poses manifold issues in the oil industry.Experimentally evaluating this phenomenon may be costly and time-consuming.In contrast,machine learning models have proven effective i...The stability of acid-crude oil emulsion poses manifold issues in the oil industry.Experimentally evaluating this phenomenon may be costly and time-consuming.In contrast,machine learning models have proven effective in predicting and evaluating various phenomena.This research is the first of its kind to assess the stability of acid-crude oil emulsion,employing various classification machine learning models.For this purpose,a data set consisting of 249 experimental data points belonging to 11 different crude oil samples was collected.Three tree-based models,namely decision tree(DT),random forest(RF),and categorical boosting(CatBoost),as well as three artificial neural network models,namely radial basis function(RBF),multi-layer perceptron(MLP) and convolutional neural network(CNN),were developed based on the properties of crude oil,acid,and protective additive.The CatBoost model obtained the highest accuracy with 0.9687,followed closely by the CNN model with 0.9673.In addition,confusion matrix findings showed the superiority of the CatBoost model.Finally,by applying the SHapley Additive exPlanations(SHAP) method to analyze the impact of input parameters,it was found that the crude oil viscosity has the most significant effect on the model's output with the mean absolute SHAP value of 0.88.展开更多
Stable HCl-crude oil emulsion and its subsequent sludge formation,with detrimental impacts on oil production,may stem from acid stimulation.One major ambiguity in this process is to discern the most influential compon...Stable HCl-crude oil emulsion and its subsequent sludge formation,with detrimental impacts on oil production,may stem from acid stimulation.One major ambiguity in this process is to discern the most influential component of crude oil on the stability of formed emulsions.This fundamental question has not adequately been addressed in previous studies.In this work,the impact of de-asphalted part of crude oil(maltene)has been investigated on the acid-induced emulsion and sludge separately.Accordingly,the emulsion phase separation and the amount of formed sludge have been compared for four crude oils and their maltene samples for different concentrations of ferric ion and acidic pH values.The results of phase separation,as a criterion for emulsion stability,showed that crude oil samples formed 6 to 25 percent more stable emulsions than maltene samples,when using blank HCl.The emulsions of maltene and spent acid(pH=2)broke completely during the first 15 min after emulsification.In addition,the maltene components usually had less contribution to sludge formation in the presence of blank HCl.It was concluded that asphaltene is the key component during interaction with HCl.However,the maltene of one crude sample formed higher acid sludge in comparison to its crude oil.For acid solutions containing 3000 ppm of ferric ion,the emulsion stability increased for all crude oil and maltene samples.Moreover,the stability of some maltene emulsions increased to 48%and 100%in the presence of 3000 ppm of ferric ions.The presence of ferric ions caused forming very stable emulsions,while most of the sludge formation took place at higher pH values.Finally,it was also attained that emulsion and sludge formations could happen simultaneously.展开更多
During heavy oil recovery in the Bohai Oilfield,substantial emulsification of oil and water occurred,primarily forming water-in-oil emulsions.This phenomenon could alter fluid dynamics within the subsurface porous med...During heavy oil recovery in the Bohai Oilfield,substantial emulsification of oil and water occurred,primarily forming water-in-oil emulsions.This phenomenon could alter fluid dynamics within the subsurface porous media,potentially impacting well production performance.To elucidate the properties of water-in-oil emulsions and their associated liquid resistance effects,this study conducted a series of rheological tests,microscopic examinations,and injection experiments.The results show that the droplet size and distribution of water-in-oil emulsions were primarily influenced by shear rate and water content,which in turn modified emulsion viscosity.The stability of water-in-oil emulsions was reduced when they flowed through porous media.The increase in emulsion viscosity and the liquid resistance effect collectively enhanced the seepage resistance of water-in-oil emulsions flowing through porous media.Notably,when the emulsion droplet size exceeded the pore throat size,over 90%of the total seepage resistance was attributable to the liquid resistance effect.Conversely,when the majority of the emulsion droplets were smaller than the pore throat,the viscosity accounted for more than 60%of the seepage resistance.Water-in-oil emulsions flowed through cores with permeabilities ranging from 50 to 100 mD,exhibiting threshold pressure gradients between 35 and 43 MPa/m.At a core permeability of 300 mD,the threshold pressure gradient was significantly reduced to 1 MPa/m.The presence of a waterin-oil emulsion in the reservoir could result in a production pressure differential falling below the threshold pressure,thereby reducing reservoir productivity.展开更多
The influence of petroleum sulphonate (TRS) on interfacial properties and stability of the emulsions formed by formation water and asphaltene, resin and crude model oils from Gudong crude oil was investigated by measu...The influence of petroleum sulphonate (TRS) on interfacial properties and stability of the emulsions formed by formation water and asphaltene, resin and crude model oils from Gudong crude oil was investigated by measurement of interfacial shear viscosity, interfacial tension (IFT) and emulsion stability. With increasing petroleum sulphonate concentration, IFT between the formation water and the asphaltene, resin and crude model oils decreases significantly. The interfacial shear viscosity and emulsion stability of asphaltene and crude model oil system increase for the petroleum sulphonate concentration in the range 0.1% to 0.3%, and decrease slightly when the concentration of the surfactant is 0.5%. There exists a close correlation between the interfacial shear viscosity and the stability of the emulsions formed by asphaltene or crude model oils and petroleum sulphonate solution.The stability of the emulsions is determined by the strength of the interfacial film formed of petroleum sulphonate molecules and the natural interfacial active components in the asphaltene fraction and the crude oil. The asphaltene in the crude oil plays a major role in determining the interfacial properties and the stability of the emulsions.展开更多
In petroleum industry, crude oil emulsions are commonly formed in oilfields. The asphaltenes and fine particles in crude oil may affect the stability of the emulsions by adsorbing at the water/oil interface. In this r...In petroleum industry, crude oil emulsions are commonly formed in oilfields. The asphaltenes and fine particles in crude oil may affect the stability of the emulsions by adsorbing at the water/oil interface. In this research, the effect of silica nanoparticles and asphaltenes on emulsion stability is explored first. The asphaltenes are proved to benefit emulsion stability. Unlike the asphaltenes, however, the modified silica nanoparticles may have positive or negative effect on emulsion stability, depending on the asphaltene concentration and aggregation degree in the emulsions. Further, it is confirmed by conducting interfacial experiment that the asphaltenes and particles can adsorb at the interface simultaneously and determine the properties of the interfacial layer. More in-depth experiments concerning contact angle and asphaltene adsorption amount on the particles indicate that the asphaltenes can modify the wettability of the particles. Higher concentration and lower aggregation degree of the asphaltenes can increase their adsorption amount on the surface of particles and then improve the modification effectiveness of the particles. Resultantly, the particles with good modification effectiveness can enhance the emulsion stability while the particles with poor modification effectiveness will weaken the emulsion stability.展开更多
Objective: To determine hydrophilic–lipophilic balance(HLB) value, stability of formulate emulsion and properties of sacha inchi oil.Methods: The physiochemical characteristics of sacha inchi oil were first investiga...Objective: To determine hydrophilic–lipophilic balance(HLB) value, stability of formulate emulsion and properties of sacha inchi oil.Methods: The physiochemical characteristics of sacha inchi oil were first investigated.Free radical scavenging property was studied by DPPH assay. HLB value of sacha inchi oil was experimentally determined by preparing the emulsion using emulsifiers at different HLB value. Sacha inchi oil emulsion was prepared using the obtained HLB and its stability was conducted by centrifugation, temperature cycling, and accelerated stability test. The efficiency of the prepared emulsion was clinically investigated by 15 volunteers. The primary skin irritation was performed using closed patch test. Subjective sensory assessment was evaluated by using 5-point hedonic scale method.Results: Peroxide value of sacha inchi oil was 18.40 meq O2/kg oil and acid value was1.86 KOH/g oil. The major fatty acids are omega-3(44%), omega-6(35%) and omega-9(9%). The vitamin E content was 226 mg/100 g oil. Moreover, sacha inchi oil(167 ppm)and its emulsion showed 85% and 89% DPPH inhibition, respectively. The experimental HLB value of sacha inchi oil was 8.5. The sacha inchi oil emulsion exhibited good stability after stability test. The emulsion was classified as non-irritant after tested by primary skin irritation method. The skin hydration value significantly increased from38.59 to 45.21(P < 0.05) after applying sacha inchi oil emulsion for 1 month and the overall product satisfaction of volunteers after use was with score of 4.2.Conclusions: This work provides information on HLB value and emulsion properties of sacha inchi oil which is useful for cosmetic and pharmaceutical application.展开更多
Mild thermal treatment is an important partial upgrading technique to enable bitumen pipeline transportation,but no attention has been paid to the impact of mild thermal treatment on the emulsification behavior of eme...Mild thermal treatment is an important partial upgrading technique to enable bitumen pipeline transportation,but no attention has been paid to the impact of mild thermal treatment on the emulsification behavior of emerging partially upgraded bitumen.Asphaltene compounds are active emulsion stabilizers in bitumen oil.The emulsion stabilizing capacity of bitumen asphaltenes was investigated,before and after a mild thermal treatment at 400℃.The structural morphology and mechanical property of the asphaltene interfacial films were analyzed by using a combination of cryo-SEM,Langmuir trough,and Brewster angle microscopy.The thermal treatment significantly enhanced the emulsion stabilizing capacity of bitumen asphaltenes;the interfacial films formed by the thermally treated asphaltene samples appeared to be rougher and thicker with more abundant micron-scale wrinkle structures.The interfacial corrugation may intensify the mechanical stability/flexibility of the asphaltene films and consequently strengthen the stability of emulsion droplet.展开更多
An innovational test method was developed on the basis of redefinition of the emulsion stability. The stability was characterized by relative volume percentage of disperse phase demulsified thoroughly from the top par...An innovational test method was developed on the basis of redefinition of the emulsion stability. The stability was characterized by relative volume percentage of disperse phase demulsified thoroughly from the top part and the bottom part of an emulsion sample, each weighting the same amount, after being settled for a given time at constant temperature. Three series of emulsions were prepared and tested successfully, which were emulsions of paraffin oil and water stabilized with polyoxyethylene lauryl ether series (AEO3 and AEO9) at various HLBs, and emulsions of rapeseed oil and water stablized with sorbitan monoleate (Span80) and each of polyoxyethylene (20) sorbitan carboxylic esters (Tween20, Tween40, Tween60, Tween80 and Tween85) at different HLBs. It provedthat this method is especially workable while the boundaries are opaque in a wide range of HLBs and is capable of offering an accurate optimum HLB.展开更多
Alkenyl succinic anhydride(ASA) is a popular paper-sizing agent that is generally added to papermaking systems as an aqueous emulsion. Herein, we reviewed the recent work focusing on ASA emulsions stabilized by solid ...Alkenyl succinic anhydride(ASA) is a popular paper-sizing agent that is generally added to papermaking systems as an aqueous emulsion. Herein, we reviewed the recent work focusing on ASA emulsions stabilized by solid particles. Solid particle-stabilized ASA emulsions generally possess high ASA content and exhibit good sizing performance. The particles that have been used to stabilize ASA emulsions typically include montmorillonite, laponite, alumina, TiO_2, Fe_3O_4, polyaluminum sulfate(PAS), and cellulose nanocrystals(CNCs). Montmorillonite is the first extensively studied particle stabilizer for ASA emulsions. Laponite is undoubtedly the most competent particle stabilizer for preparing ASA emulsions with high sizing efficiency. Montmorillonite and laponite can be used individually as stabilizers after modification or as co-stabilizers with other particles or polymers. TiO_2, alumina, PAS, and CNCs are commonly used as stabilizers either individually or with other particles.展开更多
Profile control is utilized to redirect the injection water to low permeability region where a large amount of crude oil lies.Performed gel particles are the commonly used agent for redistributing water by blocking th...Profile control is utilized to redirect the injection water to low permeability region where a large amount of crude oil lies.Performed gel particles are the commonly used agent for redistributing water by blocking the pores in high permeability region.But the capability of deep penetration of performed gel particles is poor.Here,we formulate nanoparticle stabilized emulsion(NSE).The stability and the effect of NSE on the fluid redirection in a three-dimensional porous medium were investigated.By usingμ-PIV(particle image velocimetry),it was found that the velocity gradient of continuous fluid close to the nanoparticle stabilized droplets is much higher than that close to surfactant stabilized droplets.NSE behaves as solid particle in preferential seepage channels,which will decrease effectively the permeability,thereby redirecting the subsequent injection water.Furthermore,NSE shows high stability compared with emulsion stabilized by surfactant in static and dynamic tests.In addition,water flooding tests also confirm that the NSE can significantly reduce the permeability of porous media and redirect the fluid flow.Our results demonstrate NSE owns high potential to act as profile control agent in deep formation.展开更多
In order to prepare cellulose nanocrystals( CNCs)-coated polylactide( PLA) microspheres for the use of drug delivery and tissue engineering,a Pickering emulsion route was applied. The stable Pickering emulsions were p...In order to prepare cellulose nanocrystals( CNCs)-coated polylactide( PLA) microspheres for the use of drug delivery and tissue engineering,a Pickering emulsion route was applied. The stable Pickering emulsions were prepared using CNCs as efficient stabilizers without any additional surfactant. The microspheres were successfully fabricated after volatilization of the solvent. What's more,the size of microspheres could be controlled by fabrication parameters.展开更多
Objective A commercially available reference product was“re-engineered”and the target emulsion was formulated to contain the same energy density,as well as the same percentage of energy sources,as the reference prod...Objective A commercially available reference product was“re-engineered”and the target emulsion was formulated to contain the same energy density,as well as the same percentage of energy sources,as the reference product.The particle size and distribution,polydispersity index(PDI),and zeta-potential of emulsions were measured as indices to analyse the quality of the emulsions.Methods The centrifugal stability(Ke)was examined as the main measure of the stability of the target emulsion.Critical parameters affecting the stability of emulsions were also determined,while the temperature was fixed at 30℃,shear speed at 3500 r/min,and shear time was 15 min.The optimal quantity of emulsifier was also studied in the crude homogenate.Results A relatively stable emulsion could be obtained by using PC-50 at a dosage of 2%as the emulsifier.A 2∶1 proportion of whey protein to casein,a 1∶1 proportion of maltodextrin(DE 10-15)to maltodextrin(DE 15-20)and medium chain triglyceride(MCT)in powder form were used to obtain the most desirable emulsion.Conclusion This study explored the critical parameters that influence the stability of a total nutrition enteral emulsion designed for cancer patients,providing useful information for further industrialisation of this and other emulsion products.展开更多
The emulsion stability of oilfield produced water is related to the oil-water interfacial film strength and the zeta potential of the oil droplets. We investigated the effects of water treatment agents （corrosion inh...The emulsion stability of oilfield produced water is related to the oil-water interfacial film strength and the zeta potential of the oil droplets. We investigated the effects of water treatment agents （corrosion inhibitor SL-2, scale inhibitor HEDP, germicide 1227, and flocculant polyaluminium chloride PAC） on the stability of oilfield produced water. The influence of these treatment agents on oil-water interfacial properties and the mechanism of these agents acting on the oilfield produced water were studied by measuring the interfacial shear viscosity, interfacial tension and zeta electric potential. The results indicated that the scale inhibitor HEDP could increase the oil-water interfacial film strength, and it could also increase the absolute value of the zeta potential of oil droplets. HEDP played an important role in the stability of the emulsion. Polyaluminum chloride （PAC） reduced the stability of the emulsion by considerably decreasing the absolute value of the zeta potential of oil droplets. Corrosion inhibitor SL-2 and germicide 1227 could decrease the oil-water interfacial tension, whereas they had little influence on oil-water interfacial shear viscosity and oil-water interfacial electricity properties.展开更多
The production and properties of the biosurfactant synthesized by Bacillus subtilis CCTCC AB93108 were studied. The maximum concentration of the surfactant is 1.64 g/L when the bacteria grow in a medium supplemented w...The production and properties of the biosurfactant synthesized by Bacillus subtilis CCTCC AB93108 were studied. The maximum concentration of the surfactant is 1.64 g/L when the bacteria grow in a medium supplemented with glucose as carbon sources. The isolated biosurfactant is a complex of protein and polysaccharide without lipids. It reduces the surface tension of distilled water to 45.9 mN/m, and its critical micelle concentration (CMC) is 2.96 g/L. It can stabilize emulsions of several aromatic and aliphatic hydrocarbons, such as benzene, xylene, n-pentane, n-nonane, gasoline and diesel oil. It presents high emulsification activity and stability in a wide range of temperature (4-100 ℃) and a long period of duration.展开更多
The oil-in-water emulsion drilling fluids, prepared by adding 5～12% (by volume) of mineral oil (or diesel) to water-based muds, have been widely used for stuck-pipe prevention in the Shengli Oilfield. In some cases, ...The oil-in-water emulsion drilling fluids, prepared by adding 5～12% (by volume) of mineral oil (or diesel) to water-based muds, have been widely used for stuck-pipe prevention in the Shengli Oilfield. In some cases, the emulsion stability of this kind of mud system is not strong enough to meet the requirements of drilling operations. To overcome this drawback, a solid emulsifier, which is characterized by its very small particle size and special wetting behavior (slightly water-wet), has been developed and successfully applied to improve the emulsion stability and other performances of these drilling fluids. Prior to the development of this technology, an extensive study was conducted to deal with the influence of various kinds of finely divided insoluble solid particles on oil/water emulsification. The substances used include bentonite, organophilic clay, kaolinite, barite, two kinds of calcium carbonate with different particle sizes, two kinds of silica with different wetting behaviors, and a newly developed solid emulsifier. Both the emulsion stability experiments and the drop coalescence experiments are performed to evaluate the contribution of these particles to emulsification. The measured final emulsion volume disappears after 12 hours and the half-life for water and oil drops are used as the measures of emulsion stability. The experimental data show that the type, size, concentration and wettability of the particles, and the presence of some surfactants control the type and stability of emulsions for a given oil/water system, and the fine particles of the solids emulsifier provide the most effective stabilization for water-continuous emulsions compared with other kinds of particles. Meanwhile, it can be observed that these particles also stabilize oil-continuous emulsions effectively in some cases since their wetting behavior is close to neutral. The O/W emulsion mud stabilized by the newly developed solid emulsifier has become one of the major mud systems used in directional and horizontal well drilling in the Shengli Oilfield. In addition to the improvement of emulsion stability, this solid emulsifier has the advantages of improving the lubricity of mud cake and is beneficial to the control of rheological properties and filtration.展开更多
Bread spread is one of the fundamental foods in human diets. Generally, cheese spread, butter, chocolate spread, and margarine are the most consumed. In the last decade, a new concept alimentary has been integrated, i...Bread spread is one of the fundamental foods in human diets. Generally, cheese spread, butter, chocolate spread, and margarine are the most consumed. In the last decade, a new concept alimentary has been integrated, it was low fat spread or functional spread. This work is an attempt to formulate and optimize new low-fat spreads based on olive oil and honey using a response surface methodology box-benken design. To optimize its stability and its textural properties under the effects of three factors, beeswax content, stirring time, and stirring speed. Results revealed that the best mixture was the formulation that contained 1% beeswax, 79% honey, and 20% olive oil, formulated under 6.39 min of time stirring at 15,428 rpm speed. The beeswax was the major factor showing the highest effect on all the properties of spreads.展开更多
With the enhancement of environmental protection awareness, the requirements on drilling fluid are increasingly strict, and the use of ordinary oil-based drilling fluid has been strictly restricted. In order to solve ...With the enhancement of environmental protection awareness, the requirements on drilling fluid are increasingly strict, and the use of ordinary oil-based drilling fluid has been strictly restricted. In order to solve the environmental protection and oil-gas reservoir protection problems of offshore oil drilling, a new synthetic basic drilling fluid system is developed. The basic formula is as follows: a basic fluid (80% Linear a-olefin + 20% Simulated seawater) + 2.5% nano organobentonite + 3.5% emulsifier RHJ-5<sup>#</sup> + 2.5% fluid loss agent SDJ-1 + 1.5% CaO + the right amount of oil wetting barite to adjust the density, and a multifunctional oil and gas formation protective agent YRZ has been developed. The performance was evaluated using a high-low-high-temperature rheometer, a high-temperature and high-pressure demulsification voltage tester, and a high-temperature and high-pressure dynamic fluid loss meter. The results show that the developed synthetic based drilling fluid has good rheological property, demulsification voltage ≥ 500 V, temperature resistance up to 160°C, high temperature and high pressure filtration loss < 3.5 mL. After adding 2% - 5% YRZ into the basic formula of synthetic based drilling fluid, the permeability recovery value exceeds 90% and the reservoir protection effect is excellent. The new synthetic deepwater drilling fluid is expected to have a good application prospect in offshore deepwater drilling.展开更多
The nitrogen oxide(NOx)release of diesel engines can be reduced using water in diesel emulsion fuel without any engine modification.In the present paper,different formulations of water in diesel emulsion fuels were pr...The nitrogen oxide(NOx)release of diesel engines can be reduced using water in diesel emulsion fuel without any engine modification.In the present paper,different formulations of water in diesel emulsion fuels were prepared by ultrasonic irradiation.The water droplet size in the emulsion,polydisperisty index,and the stability of prepared fuel was examined,experimentally.Afterwards,the performance characteristics and exhaust emission of a single cylinder air-cooled diesel engine were investigated using different water in diesel emulsion fuels.The effect of water content(in the range of 5%-10% by volume),surfactant content(in the range of 0.5%-2% by volume),and hydrophilic-lipophilic balance(HLB)(in the range of 5-8)was examined using Box-Behnken design(BBD)as a subset of response surface methodology(RSM).Considering multi-objective optimization,the best formulation for the emulsion fuel was found to be 5%water,2% surfactant,and HLB of 6.8.A comparison was made between the best emulsion fuel and the neat diesel fuel for engine performance and emission characteristics.A considerable decrease in the nitrogen oxide emission(-18.24%)was observed for the best emulsion fuel compared to neat diesel fuel.展开更多
Picketing emulsions were prepared using mixed particles of silica and calcite as emulsifiers. The effects of the silica content in the mixed particles on the stability and the drop size of the Picketing emulsions were...Picketing emulsions were prepared using mixed particles of silica and calcite as emulsifiers. The effects of the silica content in the mixed particles on the stability and the drop size of the Picketing emulsions were investigated. The results showed that the Picketing emulsions were of the oil-in-water type. With increasing silica content in the mixed partides, the stability and the drop size of the Pickering emulsions decreased. Larger silica particles had more influence on the stability of the emulsions, while smaller ones had more influence on the drop size of the emulsions. The effect of the silica particles on the emulsions was attributed to their adsorptive behavior at the oil-water interfaces of the Picketing emulsions.展开更多
基金supported by the Natural Science Foundation of Shandong Province(ZR2021ME007)the National Natural Science Foundation in China(51574267)the Key Projects of China National Key Research and Development Plan(2019YFA0708703)。
文摘During oil displacement,surfactants often encounter challenges such as emulsion instability and channeling,which can compromise their efficiency.To address these issues,polymer microspheres were synthesized via reverse microemulsion polymerization using acrylamide,2-methyl-2-acrylamidopropane sulfonic acid,and stearyl methacrylate as monomers,with N,N-methylenebisacrylamide as the crosslinker.The microspheres were then combined with sodium alkyl alcohol polyoxyethylene ether carboxylate to enhance emulsion stability and expand the swept volume of surfactant.A stable reverse microemulsion system was prepared using the maximum water solubilization rate as the indicator,and microspheres were synthesized based on this system.The ability of the microspheres to enhance emulsion stability was systematically evaluated.The plugging performance and enhanced oil recovery(EOR)efficiency of the microsphere/surfactant composite system were assessed through core seepage and oil displacement experiments.The experimental results demonstrated that microspheres were successfully prepared in a water-in-oil reverse microemulsion system with a solubilization rate of 42%.The emulsion stability was evaluated under an oil-to-water ratio of 7:3,a temperature of 80℃,and a salinity of 44,592 mg/L,by manually shaking the test tube five times.It was observed that the complete phase separation time of the emulsion increased from 10 to 120 min after the addition of microspheres.Under different permeability conditions(100×10^(-3),300×10^(-3),500×10^(-3)μm^(2)),the recovery efficiency of the composite system increased by 4.5%,8.3%,and 4.8%,respectively,compared to a single surfactant system.The microspheres developed in this study enhanced emulsion stability and increased the swept volume of surfactant within the formation,significantly boosting its oil recovery efficiency.
文摘The stability of acid-crude oil emulsion poses manifold issues in the oil industry.Experimentally evaluating this phenomenon may be costly and time-consuming.In contrast,machine learning models have proven effective in predicting and evaluating various phenomena.This research is the first of its kind to assess the stability of acid-crude oil emulsion,employing various classification machine learning models.For this purpose,a data set consisting of 249 experimental data points belonging to 11 different crude oil samples was collected.Three tree-based models,namely decision tree(DT),random forest(RF),and categorical boosting(CatBoost),as well as three artificial neural network models,namely radial basis function(RBF),multi-layer perceptron(MLP) and convolutional neural network(CNN),were developed based on the properties of crude oil,acid,and protective additive.The CatBoost model obtained the highest accuracy with 0.9687,followed closely by the CNN model with 0.9673.In addition,confusion matrix findings showed the superiority of the CatBoost model.Finally,by applying the SHapley Additive exPlanations(SHAP) method to analyze the impact of input parameters,it was found that the crude oil viscosity has the most significant effect on the model's output with the mean absolute SHAP value of 0.88.
文摘Stable HCl-crude oil emulsion and its subsequent sludge formation,with detrimental impacts on oil production,may stem from acid stimulation.One major ambiguity in this process is to discern the most influential component of crude oil on the stability of formed emulsions.This fundamental question has not adequately been addressed in previous studies.In this work,the impact of de-asphalted part of crude oil(maltene)has been investigated on the acid-induced emulsion and sludge separately.Accordingly,the emulsion phase separation and the amount of formed sludge have been compared for four crude oils and their maltene samples for different concentrations of ferric ion and acidic pH values.The results of phase separation,as a criterion for emulsion stability,showed that crude oil samples formed 6 to 25 percent more stable emulsions than maltene samples,when using blank HCl.The emulsions of maltene and spent acid(pH=2)broke completely during the first 15 min after emulsification.In addition,the maltene components usually had less contribution to sludge formation in the presence of blank HCl.It was concluded that asphaltene is the key component during interaction with HCl.However,the maltene of one crude sample formed higher acid sludge in comparison to its crude oil.For acid solutions containing 3000 ppm of ferric ion,the emulsion stability increased for all crude oil and maltene samples.Moreover,the stability of some maltene emulsions increased to 48%and 100%in the presence of 3000 ppm of ferric ions.The presence of ferric ions caused forming very stable emulsions,while most of the sludge formation took place at higher pH values.Finally,it was also attained that emulsion and sludge formations could happen simultaneously.
基金financially supported by the National Natural Science Foundation of China(No.ZX20230212)。
文摘During heavy oil recovery in the Bohai Oilfield,substantial emulsification of oil and water occurred,primarily forming water-in-oil emulsions.This phenomenon could alter fluid dynamics within the subsurface porous media,potentially impacting well production performance.To elucidate the properties of water-in-oil emulsions and their associated liquid resistance effects,this study conducted a series of rheological tests,microscopic examinations,and injection experiments.The results show that the droplet size and distribution of water-in-oil emulsions were primarily influenced by shear rate and water content,which in turn modified emulsion viscosity.The stability of water-in-oil emulsions was reduced when they flowed through porous media.The increase in emulsion viscosity and the liquid resistance effect collectively enhanced the seepage resistance of water-in-oil emulsions flowing through porous media.Notably,when the emulsion droplet size exceeded the pore throat size,over 90%of the total seepage resistance was attributable to the liquid resistance effect.Conversely,when the majority of the emulsion droplets were smaller than the pore throat,the viscosity accounted for more than 60%of the seepage resistance.Water-in-oil emulsions flowed through cores with permeabilities ranging from 50 to 100 mD,exhibiting threshold pressure gradients between 35 and 43 MPa/m.At a core permeability of 300 mD,the threshold pressure gradient was significantly reduced to 1 MPa/m.The presence of a waterin-oil emulsion in the reservoir could result in a production pressure differential falling below the threshold pressure,thereby reducing reservoir productivity.
基金国家重点基础研究发展计划(973计划)，an International Cooperation Research Program
文摘The influence of petroleum sulphonate (TRS) on interfacial properties and stability of the emulsions formed by formation water and asphaltene, resin and crude model oils from Gudong crude oil was investigated by measurement of interfacial shear viscosity, interfacial tension (IFT) and emulsion stability. With increasing petroleum sulphonate concentration, IFT between the formation water and the asphaltene, resin and crude model oils decreases significantly. The interfacial shear viscosity and emulsion stability of asphaltene and crude model oil system increase for the petroleum sulphonate concentration in the range 0.1% to 0.3%, and decrease slightly when the concentration of the surfactant is 0.5%. There exists a close correlation between the interfacial shear viscosity and the stability of the emulsions formed by asphaltene or crude model oils and petroleum sulphonate solution.The stability of the emulsions is determined by the strength of the interfacial film formed of petroleum sulphonate molecules and the natural interfacial active components in the asphaltene fraction and the crude oil. The asphaltene in the crude oil plays a major role in determining the interfacial properties and the stability of the emulsions.
基金Support from the National Natural Science Foundation of China(Grant No. 51704315)。
文摘In petroleum industry, crude oil emulsions are commonly formed in oilfields. The asphaltenes and fine particles in crude oil may affect the stability of the emulsions by adsorbing at the water/oil interface. In this research, the effect of silica nanoparticles and asphaltenes on emulsion stability is explored first. The asphaltenes are proved to benefit emulsion stability. Unlike the asphaltenes, however, the modified silica nanoparticles may have positive or negative effect on emulsion stability, depending on the asphaltene concentration and aggregation degree in the emulsions. Further, it is confirmed by conducting interfacial experiment that the asphaltenes and particles can adsorb at the interface simultaneously and determine the properties of the interfacial layer. More in-depth experiments concerning contact angle and asphaltene adsorption amount on the particles indicate that the asphaltenes can modify the wettability of the particles. Higher concentration and lower aggregation degree of the asphaltenes can increase their adsorption amount on the surface of particles and then improve the modification effectiveness of the particles. Resultantly, the particles with good modification effectiveness can enhance the emulsion stability while the particles with poor modification effectiveness will weaken the emulsion stability.
文摘Objective: To determine hydrophilic–lipophilic balance(HLB) value, stability of formulate emulsion and properties of sacha inchi oil.Methods: The physiochemical characteristics of sacha inchi oil were first investigated.Free radical scavenging property was studied by DPPH assay. HLB value of sacha inchi oil was experimentally determined by preparing the emulsion using emulsifiers at different HLB value. Sacha inchi oil emulsion was prepared using the obtained HLB and its stability was conducted by centrifugation, temperature cycling, and accelerated stability test. The efficiency of the prepared emulsion was clinically investigated by 15 volunteers. The primary skin irritation was performed using closed patch test. Subjective sensory assessment was evaluated by using 5-point hedonic scale method.Results: Peroxide value of sacha inchi oil was 18.40 meq O2/kg oil and acid value was1.86 KOH/g oil. The major fatty acids are omega-3(44%), omega-6(35%) and omega-9(9%). The vitamin E content was 226 mg/100 g oil. Moreover, sacha inchi oil(167 ppm)and its emulsion showed 85% and 89% DPPH inhibition, respectively. The experimental HLB value of sacha inchi oil was 8.5. The sacha inchi oil emulsion exhibited good stability after stability test. The emulsion was classified as non-irritant after tested by primary skin irritation method. The skin hydration value significantly increased from38.59 to 45.21(P < 0.05) after applying sacha inchi oil emulsion for 1 month and the overall product satisfaction of volunteers after use was with score of 4.2.Conclusions: This work provides information on HLB value and emulsion properties of sacha inchi oil which is useful for cosmetic and pharmaceutical application.
基金supported by National Natural Science Foundation of China(52004266)the Opening Fund of State Key Laboratory of Heavy Oil Processing(SKLOP202001001)+1 种基金the Key R&D Program of Shandong,China(2019JZZY020502)independent innovation project of China University of Petroleum(21CX06008A)
文摘Mild thermal treatment is an important partial upgrading technique to enable bitumen pipeline transportation,but no attention has been paid to the impact of mild thermal treatment on the emulsification behavior of emerging partially upgraded bitumen.Asphaltene compounds are active emulsion stabilizers in bitumen oil.The emulsion stabilizing capacity of bitumen asphaltenes was investigated,before and after a mild thermal treatment at 400℃.The structural morphology and mechanical property of the asphaltene interfacial films were analyzed by using a combination of cryo-SEM,Langmuir trough,and Brewster angle microscopy.The thermal treatment significantly enhanced the emulsion stabilizing capacity of bitumen asphaltenes;the interfacial films formed by the thermally treated asphaltene samples appeared to be rougher and thicker with more abundant micron-scale wrinkle structures.The interfacial corrugation may intensify the mechanical stability/flexibility of the asphaltene films and consequently strengthen the stability of emulsion droplet.
基金the National Natural Science Foundation of China (No. 29736170).
文摘An innovational test method was developed on the basis of redefinition of the emulsion stability. The stability was characterized by relative volume percentage of disperse phase demulsified thoroughly from the top part and the bottom part of an emulsion sample, each weighting the same amount, after being settled for a given time at constant temperature. Three series of emulsions were prepared and tested successfully, which were emulsions of paraffin oil and water stabilized with polyoxyethylene lauryl ether series (AEO3 and AEO9) at various HLBs, and emulsions of rapeseed oil and water stablized with sorbitan monoleate (Span80) and each of polyoxyethylene (20) sorbitan carboxylic esters (Tween20, Tween40, Tween60, Tween80 and Tween85) at different HLBs. It provedthat this method is especially workable while the boundaries are opaque in a wide range of HLBs and is capable of offering an accurate optimum HLB.
基金funded by the National Natural Science Foundation of China(Grant Nos.31270625 and 21406122)
文摘Alkenyl succinic anhydride(ASA) is a popular paper-sizing agent that is generally added to papermaking systems as an aqueous emulsion. Herein, we reviewed the recent work focusing on ASA emulsions stabilized by solid particles. Solid particle-stabilized ASA emulsions generally possess high ASA content and exhibit good sizing performance. The particles that have been used to stabilize ASA emulsions typically include montmorillonite, laponite, alumina, TiO_2, Fe_3O_4, polyaluminum sulfate(PAS), and cellulose nanocrystals(CNCs). Montmorillonite is the first extensively studied particle stabilizer for ASA emulsions. Laponite is undoubtedly the most competent particle stabilizer for preparing ASA emulsions with high sizing efficiency. Montmorillonite and laponite can be used individually as stabilizers after modification or as co-stabilizers with other particles or polymers. TiO_2, alumina, PAS, and CNCs are commonly used as stabilizers either individually or with other particles.
基金supported by the National Natural Science Foundation of China(U1663206,51704313)the Taishan Scholar Climbing Program in Shandong Province(tspd20161004)the Fundamental Research Funds for the Central Universities(18CX02028A)
文摘Profile control is utilized to redirect the injection water to low permeability region where a large amount of crude oil lies.Performed gel particles are the commonly used agent for redistributing water by blocking the pores in high permeability region.But the capability of deep penetration of performed gel particles is poor.Here,we formulate nanoparticle stabilized emulsion(NSE).The stability and the effect of NSE on the fluid redirection in a three-dimensional porous medium were investigated.By usingμ-PIV(particle image velocimetry),it was found that the velocity gradient of continuous fluid close to the nanoparticle stabilized droplets is much higher than that close to surfactant stabilized droplets.NSE behaves as solid particle in preferential seepage channels,which will decrease effectively the permeability,thereby redirecting the subsequent injection water.Furthermore,NSE shows high stability compared with emulsion stabilized by surfactant in static and dynamic tests.In addition,water flooding tests also confirm that the NSE can significantly reduce the permeability of porous media and redirect the fluid flow.Our results demonstrate NSE owns high potential to act as profile control agent in deep formation.
基金National Key Technology R&D Program of China(No.2014BAC13B02)National Natural Science Foundation of China(No.51403035)+1 种基金Programme of Introducing Talents of Discipline to Universities,China(No.105-07-005735)the Fundamental Research Funds for the Central Universities,China(No.15D110510)
文摘In order to prepare cellulose nanocrystals( CNCs)-coated polylactide( PLA) microspheres for the use of drug delivery and tissue engineering,a Pickering emulsion route was applied. The stable Pickering emulsions were prepared using CNCs as efficient stabilizers without any additional surfactant. The microspheres were successfully fabricated after volatilization of the solvent. What's more,the size of microspheres could be controlled by fabrication parameters.
基金supported by funding obtained from the Key Research&Development Project of Shandong Province[no.2018YYSP008]The Open Project of Shandong Collaborative Innovation Center for Antibody Drugs[No.CIC-AD1839]Scholar Research Foundation.
文摘Objective A commercially available reference product was“re-engineered”and the target emulsion was formulated to contain the same energy density,as well as the same percentage of energy sources,as the reference product.The particle size and distribution,polydispersity index(PDI),and zeta-potential of emulsions were measured as indices to analyse the quality of the emulsions.Methods The centrifugal stability(Ke)was examined as the main measure of the stability of the target emulsion.Critical parameters affecting the stability of emulsions were also determined,while the temperature was fixed at 30℃,shear speed at 3500 r/min,and shear time was 15 min.The optimal quantity of emulsifier was also studied in the crude homogenate.Results A relatively stable emulsion could be obtained by using PC-50 at a dosage of 2%as the emulsifier.A 2∶1 proportion of whey protein to casein,a 1∶1 proportion of maltodextrin(DE 10-15)to maltodextrin(DE 15-20)and medium chain triglyceride(MCT)in powder form were used to obtain the most desirable emulsion.Conclusion This study explored the critical parameters that influence the stability of a total nutrition enteral emulsion designed for cancer patients,providing useful information for further industrialisation of this and other emulsion products.
文摘The emulsion stability of oilfield produced water is related to the oil-water interfacial film strength and the zeta potential of the oil droplets. We investigated the effects of water treatment agents （corrosion inhibitor SL-2, scale inhibitor HEDP, germicide 1227, and flocculant polyaluminium chloride PAC） on the stability of oilfield produced water. The influence of these treatment agents on oil-water interfacial properties and the mechanism of these agents acting on the oilfield produced water were studied by measuring the interfacial shear viscosity, interfacial tension and zeta electric potential. The results indicated that the scale inhibitor HEDP could increase the oil-water interfacial film strength, and it could also increase the absolute value of the zeta potential of oil droplets. HEDP played an important role in the stability of the emulsion. Polyaluminum chloride （PAC） reduced the stability of the emulsion by considerably decreasing the absolute value of the zeta potential of oil droplets. Corrosion inhibitor SL-2 and germicide 1227 could decrease the oil-water interfacial tension, whereas they had little influence on oil-water interfacial shear viscosity and oil-water interfacial electricity properties.
基金Project(IRT0719) supported by the Program for Changjiang Scholars and Innovative Research Team in University of China Project (2004AA649370) supported by the National High-Tech Research and Development Program of China+1 种基金 Projects(50425927, 50225926) supported by the Natural Foundation for Distinguished Young Scholars Project(2007F3102) supported by Technology Foundation for Creative Young Scholars of Fujian Province, China
文摘The production and properties of the biosurfactant synthesized by Bacillus subtilis CCTCC AB93108 were studied. The maximum concentration of the surfactant is 1.64 g/L when the bacteria grow in a medium supplemented with glucose as carbon sources. The isolated biosurfactant is a complex of protein and polysaccharide without lipids. It reduces the surface tension of distilled water to 45.9 mN/m, and its critical micelle concentration (CMC) is 2.96 g/L. It can stabilize emulsions of several aromatic and aliphatic hydrocarbons, such as benzene, xylene, n-pentane, n-nonane, gasoline and diesel oil. It presents high emulsification activity and stability in a wide range of temperature (4-100 ℃) and a long period of duration.
文摘The oil-in-water emulsion drilling fluids, prepared by adding 5～12% (by volume) of mineral oil (or diesel) to water-based muds, have been widely used for stuck-pipe prevention in the Shengli Oilfield. In some cases, the emulsion stability of this kind of mud system is not strong enough to meet the requirements of drilling operations. To overcome this drawback, a solid emulsifier, which is characterized by its very small particle size and special wetting behavior (slightly water-wet), has been developed and successfully applied to improve the emulsion stability and other performances of these drilling fluids. Prior to the development of this technology, an extensive study was conducted to deal with the influence of various kinds of finely divided insoluble solid particles on oil/water emulsification. The substances used include bentonite, organophilic clay, kaolinite, barite, two kinds of calcium carbonate with different particle sizes, two kinds of silica with different wetting behaviors, and a newly developed solid emulsifier. Both the emulsion stability experiments and the drop coalescence experiments are performed to evaluate the contribution of these particles to emulsification. The measured final emulsion volume disappears after 12 hours and the half-life for water and oil drops are used as the measures of emulsion stability. The experimental data show that the type, size, concentration and wettability of the particles, and the presence of some surfactants control the type and stability of emulsions for a given oil/water system, and the fine particles of the solids emulsifier provide the most effective stabilization for water-continuous emulsions compared with other kinds of particles. Meanwhile, it can be observed that these particles also stabilize oil-continuous emulsions effectively in some cases since their wetting behavior is close to neutral. The O/W emulsion mud stabilized by the newly developed solid emulsifier has become one of the major mud systems used in directional and horizontal well drilling in the Shengli Oilfield. In addition to the improvement of emulsion stability, this solid emulsifier has the advantages of improving the lubricity of mud cake and is beneficial to the control of rheological properties and filtration.
文摘Bread spread is one of the fundamental foods in human diets. Generally, cheese spread, butter, chocolate spread, and margarine are the most consumed. In the last decade, a new concept alimentary has been integrated, it was low fat spread or functional spread. This work is an attempt to formulate and optimize new low-fat spreads based on olive oil and honey using a response surface methodology box-benken design. To optimize its stability and its textural properties under the effects of three factors, beeswax content, stirring time, and stirring speed. Results revealed that the best mixture was the formulation that contained 1% beeswax, 79% honey, and 20% olive oil, formulated under 6.39 min of time stirring at 15,428 rpm speed. The beeswax was the major factor showing the highest effect on all the properties of spreads.
文摘With the enhancement of environmental protection awareness, the requirements on drilling fluid are increasingly strict, and the use of ordinary oil-based drilling fluid has been strictly restricted. In order to solve the environmental protection and oil-gas reservoir protection problems of offshore oil drilling, a new synthetic basic drilling fluid system is developed. The basic formula is as follows: a basic fluid (80% Linear a-olefin + 20% Simulated seawater) + 2.5% nano organobentonite + 3.5% emulsifier RHJ-5<sup>#</sup> + 2.5% fluid loss agent SDJ-1 + 1.5% CaO + the right amount of oil wetting barite to adjust the density, and a multifunctional oil and gas formation protective agent YRZ has been developed. The performance was evaluated using a high-low-high-temperature rheometer, a high-temperature and high-pressure demulsification voltage tester, and a high-temperature and high-pressure dynamic fluid loss meter. The results show that the developed synthetic based drilling fluid has good rheological property, demulsification voltage ≥ 500 V, temperature resistance up to 160°C, high temperature and high pressure filtration loss < 3.5 mL. After adding 2% - 5% YRZ into the basic formula of synthetic based drilling fluid, the permeability recovery value exceeds 90% and the reservoir protection effect is excellent. The new synthetic deepwater drilling fluid is expected to have a good application prospect in offshore deepwater drilling.
文摘The nitrogen oxide(NOx)release of diesel engines can be reduced using water in diesel emulsion fuel without any engine modification.In the present paper,different formulations of water in diesel emulsion fuels were prepared by ultrasonic irradiation.The water droplet size in the emulsion,polydisperisty index,and the stability of prepared fuel was examined,experimentally.Afterwards,the performance characteristics and exhaust emission of a single cylinder air-cooled diesel engine were investigated using different water in diesel emulsion fuels.The effect of water content(in the range of 5%-10% by volume),surfactant content(in the range of 0.5%-2% by volume),and hydrophilic-lipophilic balance(HLB)(in the range of 5-8)was examined using Box-Behnken design(BBD)as a subset of response surface methodology(RSM).Considering multi-objective optimization,the best formulation for the emulsion fuel was found to be 5%water,2% surfactant,and HLB of 6.8.A comparison was made between the best emulsion fuel and the neat diesel fuel for engine performance and emission characteristics.A considerable decrease in the nitrogen oxide emission(-18.24%)was observed for the best emulsion fuel compared to neat diesel fuel.
基金support from the National Natural Science Foundation(No.50572088)the Natural Science of Shaanxi Education Office(07JK313)
文摘Picketing emulsions were prepared using mixed particles of silica and calcite as emulsifiers. The effects of the silica content in the mixed particles on the stability and the drop size of the Picketing emulsions were investigated. The results showed that the Picketing emulsions were of the oil-in-water type. With increasing silica content in the mixed partides, the stability and the drop size of the Pickering emulsions decreased. Larger silica particles had more influence on the stability of the emulsions, while smaller ones had more influence on the drop size of the emulsions. The effect of the silica particles on the emulsions was attributed to their adsorptive behavior at the oil-water interfaces of the Picketing emulsions.
