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The pollution arising from emulsified oil/water mixtures is an issue of great concern owing to its fatal impact on the ecosystems and human health, which has stimulated one to develop advanced sepa...

A novel superhydrophobic/superoleophilic surface has been developed by direct surface condensation of dichloroxylene that results in a controlled coating of hyper-cross-linked polymers. Specifically, the coating was successfully applied to a melamine formaldehyde sponge and optimized by fine-tuning the reaction variables. The resulting hierarchical porous sorbents stabilized by polydimethylsiloxane exhibited an increased surface area, good physiochemical stability, high selectivity, and adsorption capacities for a variety of oils and solvents. The composite can separate oil in water emulsions with ultrahigh separation efficiency >99% over 10 cycles in liter-scale experiments, wherein the highest separation efficiency was as low as 2 ppm even with a short period of filtration, suggesting strong potential for oil/water separation and recovery.

The purification of stabilized oil/water emulsions is essential to meet the ever increasing demand for monitoring water in the environment, which has been addressed with superwetting carbon-based separation membranes. These include superhydrophilic carbon-based membranes whose progress in recent years and perspectives are reviewed in this paper. The membrane construction strategy is organized into four parts, vacuum-assisted self-assembly, sol-gel process, electrospinning, and vacuum-assisted filtration. In each section, the design strategies and their responding disadvantages have been comprehensively discussed. The challenges and prospects concerning the superhydrophilic carbon-based separation membranes for oily wastewater purification are also summarized to arouse researchers to carry out more studies.

The frequent oil spill accidents and ever-increasing oily wastewater discharged from our daily life and industries greatly threaten the ecological system as well as human health and cause heavy economic loss. To address this problem, developing advanced separation materials towards efficient oil/water emulsion separation is a critical way and has currently risen as a research focus. Electrospun nanofibrous materials with tunable wettability, controllable pore structure, diverse dimensions, and good connectivity hold great promise for meeting the requirements of emulsion separation applications. Herein, we present a comprehensive overview on the recent research regarding the design and fabrication of electrospun nanofibrous materials with special wettability and optimized porous structure for emulsion separation. We firstly introduce the emulsion separation mechanism, followed by the design principles of nanofibrous filtration materials. We subsequently discuss the preparation of electrospun nanofibrous materials beginning with selective wettability tunability (i.e., hydrophobic–oleophilic, hydrophilic–oleophobic, and switchable properties) and porous structure optimization (i.e., 2D and 3D porous structures). Based on the dimensions, nanofibrous materials can be categorized into nanofibrous membranes and nanofibrous aerogels. For each type, representative studies will be highlighted, focusing on the relationship between the synergy of the selective wettability and porous structure and emulsion separation performance. Finally, the existing challenges and future perspectives in the burgeoning field are provided.

Structured triacylglycerols play an important role in determining the functional properties of fat-based emulsion products. The aim of the study was to evaluate the physical properties of the emulsion systems manufactured on the basis of enzymatically modified rabbit fat with pumpkin seed oil in the presence of sn-1,3 regioselective lipase. Emulsions containing variable contents of thickener and variable fat ratios were analyzed for rheological behavior and particle size changes during storage, and their stability was assessed using the Turbiscan test. The results showed that the emulsion containing the majority of rabbit fat and 1 wt% of carboxymethylcellulose was characterized by the highest stability. On the other hand, the emulsions containing higher amounts of pumpkin seed oil in a fatty base characterized the lowest resistance to destabilization processes. The research confirmed the possibility of producing structured fat which can be the basis for new emulsion systems proposed as a food, cosmetic, and pharmaceutical product.

Anisotropic carbon-rich microcapsule morphologies are of great value in many applications including catalysis, energy storage, biomedicine, and osmosis-triggered drug delivery, due to an observed s...

The aim of the present study was to obtain effective and economical chemical agents for treatment of oily water from N oilfield. Component characterization of crude oil from N oilfield was carried out with gas chromatography–mass spectrometry. Optimization of non-ionic surfactants combined with dissolved air flotation (DAF) for oil removal was investigated. The results show that the crude oil consisted of nine major components which counted for 96.4% of the total composition, and the first four compounds made up 50% of the total composition. For the first four compounds, the density difference between water and each individual compound is smaller than the difference between water and normal alkanes with the same number of carbon atoms, while the solubility of these four compounds in water is greater than that of normal alkanes with the same number of carbon atoms. The characteristic of both density and solubility of the crude oil increased the oil water separation difficulty in DAF progress. The oil content in oily water from N oilfield without any treatment was 5285.95 mg/L. The oil content after treatment of DAF without any chemicals was 895.53 mg/L. Non-ionic surfactants NIS1, NIS2 and NIS3 all were effective for removing emulsified oil in oily water in DAF progress. 1200 mg/L NIS1 combined with DAF was the optimized formulation by the view of efficiency and economy. The formulation could be successfully used as a commercial product in N oilfield.

An excellent antifouling membrane with high permeate flux is required for oil/water emulsion separation due to ever-increasing oily industrial wastewater. Thus, an intriguing integration of the Omni-directional protected porous membrane that combines a high porosity nanofiber membrane with a surface segregation mechanism is established for the first time. By applying polydimethylsiloxane(PDMS)-terminated triblock copolymer, the enrichment of the hydrophilic poly(ethylene oxide) (PEO) segment and the nonpolar PDMS segment on the surface of the nanofiber endowed the nanofiber membrane with underwater oleophobicity and low oil adhesion force, exhibiting oil resistance as well as oil release property. An ultrahigh permeate flux of ∼7115 L m

The superhydrophobic composite membrane was successfully manufactured by a sol-gel method by drying the surrounding pressure. Tetraethylorthosilicate (TEOS) was used as a hydrophobic agent, while waterglass was used as a source of silica. The effect of the water to waterglass ratio (noted at 16:1 and 19:1) was evaluated to study the hydrophobic properties of the silica film coated composite membrane surface. By measuring the water contact angle on the film surface, the highest contact angle was found to occur at the ratio of 19:1, which is 143.86°. The stability of the composite membrane was also investigated by immersing the membrane in water until day 6. The results show that the synthesized composite membrane has good stability until day 6. The hydrophobicity of the surface of the silica film membrane was found to be unaffected by immersion time. Furthermore, the hydrophobicity increased after 6 days due to the interaction of alkyl groups with the humidified environment, and the surface was more stable in hydrophobicity (i.e., the contact angle of water is 153.79°). In addition, hydrophobic properties were obtained, confirming that this film has the potential to be applied to the separation of oil-water emulsions.

Alkalis, surfactants and/or polymers are usually injected in the injector wells so that the injection fluids can sweep through the reservoir and mobilize/recover more oil. However, the formation of...

Summary A state-of-the-art portable dispersion characterization rig (P-DCR) is applied to study emulsions with Exxsol™ mineral oil (ExxonMobil Chemical Company, Houston, Texas, USA), commercial distilled water, and hydrophobic silica nanoparticles (NPs) as emulsifiers. The emulsion is prepared in the P-DCR batch-separator vessel, whereby the separation kinetics are observed and recorded. In this study, emulsion breakup by the integration of oil extraction/water addition and a stirring process is investigated, which is formed with 25% water cut (WC) and 0.01% w/w hydrophobic NPs (dispersed in the oil phase). The experimental data are divided into three data sets: oil extraction only, oil-extraction/pure-water addition, and oil-extraction/water with hydrophilic NP addition. For oil extraction only (Data Set 1), the WC of the fluid mixture increases, and for a sufficient volume extraction, phase inversion occurs that results in a complete separation of the oil and water. The minimum final required NP concentration for a fast separation, defined as the minimum concentration of NP required to begin the phase separation of the emulsion, is approximately 0.0045%. The acquired data for oil-extraction/pure-water-addition (Data Set 2) result in a faster breakup of the emulsion, as compared with oil extraction only. The oil-extraction/pure-water-addition process increases the system WC faster, reaching the phase-inversion point sooner. For the oil-extraction/pure-water-addition, the final lowest WC and NP concentrations are approximately 37% and 0.006% w/w, respectively, for fast separation. Thus, it can be concluded that the NP concentration and the WC are related. Repetitive oil-extraction/pure-water-addition cycles enable determination of the combined effects of the WC and NP on the separation process. A relatively stable emulsion is reached after approximately 2 minutes from the beginning of each cycle, which enables determining whether a quick separation occurs at the current cycle. Data Set 3 (oil-extraction/water with hydrophilic NP addition) results reveal that dispersing hydrophilic NPs in water does not promote emulsion breakup. On the contrary, the NPs produce a slightly more stable emulsion. The separation process, however, does not differ significantly even for high hydrophilic NP concentrations, emphasizing the dominant role of the hydrophobic particles (dispersed in the base-case emulsion).

The presence of formation water throughout the oil well production lifetime is inevitable and consequently forming the dispersion or the emulsion due to the immiscibility of those two phases and the strong shear force acting in a rotating ESP. The formation of stable emulsion close to the inversion point will significantly increase the effective viscosity of an emulsion. This paper will present an experimental investigation of emulsion rheology inside the ESP and its effect on ESP performance under various oil viscosities and different water cuts (WC).Multi stages radial type ESP were assembled into a viscous flow loop which was initially developed by Zhang (2017). Emulsions at each WC formed from different oil viscosities, similar oil density, and surface tension. Multistage ESP was used to circulate oil/water emulsions in a close flow loop. Mass flowmeter measures both mass flow rate and fluid density, and the effective emulsion viscosity derived from an in-line pipe viscometer (PV) which locates downstream of the ESP discharge. The pressure transmitter is occupied in each pump stage to measure the pressure increment. The experiment results present in terms of pump boosting pressure at each water cut and the flow rate delivered by the pump.A Single-phase oil experiment was run at a different temperature to validate the accuracy of the PV. The data discrepancy of PV's viscosity and rotational viscometer is ±6%. The experiment results captured the emulsion's effective viscosity trend as a function of WC. A significant increase of effective viscosity close to the inversion point was observed, and it occurs due to a higher number of water droplets and hydrogen bonds which lead to an increase in hydrodynamic forces thus generating a tight emulsion. The experiment results reveal that a higher oil viscosity 70 cp reaches an inversion point at 30% - 35% WC. Meanwhile, for lower oil viscosity 45 cp reaches the inversion point at 35% - 40% WC since the turbulence increases with the decrease of oil viscosity. The increasing of effective viscosity in the water-oil emulsion induces higher pressure loss in the pump due to high friction loss, and it deteriorates the pump head. Nevertheless, as the WC increases further, the pump head will advance close to the single-phase water performance since the water turns as the continuous phase. Eventually, we can observe a prudent relationship in the pump performance in the change of emulsions effective viscosity as a function of WC. The inversion point phenomena occur at a different range of WC for different oil viscosity. Therefore, it is vital to set the possible range of operational conditions away from the inversion point. A better understanding of these aforementioned issues will lead to an accurate ESP design for optimum well performance.

Water pollution is one of society's greatest challenges. Several contaminants come into contact with large volumes of water, compromising its quality parameters. Among the contaminants, the large number of industrial activities responsible for the generation of oily effluents stand out for their impacts on the environment, affecting, for example, the maintenance of marine life and the productivity of soils. Among the treatment techniques, the use of ceramic membranes stands out for its high efficiency in the treatment of oily effluents, mainly oil-water emulsions. In line with the development of green chemistry, associated with low cost, this work aims to prepare ceramic membranes using brasgel clay, abundant in the state of Paraíba, The clay was characterized using the techniques of X-Ray Diffraction, Energy Dispersive X-ray Fluorescence Spectroscopy, Infrared Spectroscopy, Physical Nitrogen Adsorption, Thermal Analysis. The membrane was obtained through the uniaxial dry compaction technique and sintered at 650 °C, with water flow and permeate flow being carried out to obtain the membrane rejection coefficient. The results obtained indicate that the brasgel clay has all the characteristics corresponding to smectite, and the low cost membrane had a high rejection, 100.00 %, which makes it viable for the treatment of oil-water emulsions. La contaminación del agua es uno de los mayores desafíos de la sociedad. Varios contaminantes entran en contacto con grandes volúmenes de agua, comprometiendo sus parámetros de calidad. Entre los contaminantes, destaca la gran cantidad de actividades industriales responsables de la generación de efluentes oleosos por sus impactos sobre el medio ambiente, afectando, por ejemplo, el mantenimiento de la vida marina y la productividad de los suelos. Entre las técnicas de tratamiento, destaca el uso de membranas cerámicas por su alta eficiencia en el tratamiento de efluentes aceitosos, principalmente emulsiones aceite-agua. En línea con el desarrollo de la química verde, asociada al bajo costo, este trabajo tiene como objetivo la preparación de membranas cerámicas con arcilla brasgel, abundante en el territorio de Paraíba. La arcilla se caracterizó mediante las técnicas de Difracción de Rayos X (XRD), Espectroscopía de Fluorescencia de Rayos X de Dispersión de Energía, Espectroscopia infrarroja, Adsorción Física de Nitrógeno, Análisis Térmico. La membrana se obtuvo mediante la técnica de compactación seca uniaxial y sinterizado a 650 °C, realizándose flujo de agua y flujo de permeado para obtener el coeficiente de rechazo de la membrana. Los resultados obtenidos indican que la arcilla brasgel tiene todas las características correspondientes a la smectite, y la membrana de bajo costo tuvo una alta capacidad de remoción, 100.00 %, lo que la hace viable para el tratamiento de emulsiones aceite-agua. A poluição das águas é um dos grandes desafios da sociedade. Dentre os contaminantes, a grande quantidade de atividades industriais responsáveis pela geração de efluentes oleosos destaca-se pelos seus impactos causados ao meio ambiente, afetando, por exemplo, a manutenção da vida marinha e a produtividade de solos. Entre as técnicas de tratamento, o uso de membranas cerâmicas destaca-se pela alta eficiência no tratamento de efluentes oleosos, principalmente emulsões óleo-água. Em linha com o desenvolvimento da química verde, associada com o baixo custo, este trabalho tem como objetivo preparar membranas cerâmicas com uso da argila brasgel, abundante do território paraibano. A argila foi caracterizada com uso das técnicas de Difração de raios X, Espectroscopia de Fluorescência de raios X por Energia Dispersiva, Espectroscopia na região do infravermelho, Adsorção Física de Nitrogênio e Análises térmicas. A membrana foi obtida através da técnica de compactação a seco uniaxial e sinterizada a 650 oC, sendo realizados fluxo de água e fluxo permeado para obtenção do coeficiente de rejeição da membrana. Os resultados obtidos indicam que a argila brasgel apresenta todas as características correspondentes a esmectita, e a membrana de baixo custo apresentou elevada capacidade de rejeição, 100.00 %, o que a torna viável para tratamento de emulsões óleo água.

In order to solve urgent environmental problems caused by oil spills, it is meaningful and necessary to develop novel materials or techniques for efficient oil/water separation. Here, a new polyvinylidene fluoride (PVDF)-based composite membrane was successfully fabricated via a layer-by-layer self-assembly process, where the active sites were provided by pDA for the CaCO3 growth. Importantly, the CaCO3 structure could be regulated by the concentration of the precursor solution, showing the high flexibility of preparation. The as-prepared PVDF@pDA@CaCO3 membrane possessed superhydrophilic/underwater superoleophobic property and superior anti-fouling ability. In addition, the optimal PVDF@pDA@CaCO3-2 membrane showed a high permeation flux only under gravity, and the separation efficiency was as high as 99%. With the merits of low-cost and great separation performance, the as-prepared PVDF@pDA@CaCO3 membrane exhibited great potential in practical industrial applications for highly efficient oil/water emulsion separation.

Previous experiments have demonstrated the capability of graphene oxide (GO) to destabilize oil-in-water (O/W) and water-in-oil (W/O) emulsions, although there are debates on the underlying mechani...

As oil and gas production moves into deep water, the formation of gas hydrate has been a primary flow assurance challenge in the deep water pipelines. Because of the complex composition of crude oi...

The old-fashioned yet effective trans-printing method was adopted to prepare Janus fabric in the study. Nonwoven cotton fabric was firstly immersed in tetrahydrofuran solution containing P(DMAEMA-c...

Summary Experimental observations, during oil–production operations, regarding the formation of oil/water emulsions stabilized by nanoparticles and surfactants, are presented. Similarities and differences between the two types of emulsions are discussed on the basis of acquired separation profiles, as well as respective fluid interfacial properties. A state–of–the–art portable dispersion–characterization rig (PDCR) was used to run the experiments, and a surveillance camera was deployed to monitor the emulsion separation kinetics. Commercial–grade mineral oil and distilled water were used as the test fluids. Silica nanoparticles of different wettabilities, as well as surfactants with different hydrophilic-lipophilic balance (HLB) values, were deployed to investigate commonalities/differences between the surfactant– and nanoparticle–stabilized emulsions under ambient–temperature and –pressure conditions. Separation profiles were analyzed, and similar behaviors between the corresponding surfactant and nanoparticle emulsions were observed for the 25%–water–cut case. For higher water cuts, however, the surfactant–stabilized emulsions were tighter than their nanoparticle counterparts, displaying much lower separation rates. In the most severe cases, the surfactants totally inhibited the oil–creaming process and oil remained trapped in the emulsion for several hours. Multiple emulsions (O/W/O) were observed in certain cases [for hydrophilic nanoparticles and lipophilic surfactants (Span® 80)]. On the basis of the aforementioned experimental observations, the presence of surfactants caused more–severe problems for the oil/water–separation process than did the presence of an equal concentration of nanoparticles. Pendant–drop measurements indicated that the surfactants significantly lowered the interfacial tension (IFT) between the oil and water, whereas the nanoparticles did not. Finally, a literature model was used to predict separation profiles for the oil/water dispersions and evaluated by comparing the predictions with the acquired experimental data. Current research sets the benchmark for more–thorough investigations aimed at providing guidelines for a more efficient operation of separators that handle surfactant– or nanoparticle–stabilized emulsions and a better understanding of the related phenomena.

This study considers the problem of separation of oil-water emulsion in the case of oil spills. The standard methods of separation of the emulsion were presented. A unit with U-shaped separation elements has been developed. The device's operating principle was described, in which the separation of the oil-water emulsion occurs mainly due to the action of centrifugal forces arising from flow motion between the U-shaped elements and gravitational forces. The laboratory setup used for experiments was presented. The aim was to study the separation process of oil-water emulsion in a setup under varying initial temperature and initial density of the emulsion. The results showed that the device can separate the oil-water emulsion into light and heavy phases with an efficiency of at least 93.4% at a velocity of 1.39–2.15 m/s in narrow sections between the U-shaped elements. One way of improving the separation of the oil-water emulsion is to increase the working temperature. It was found that the increased efficiency of 2.5% indicates that device applicability caused the presence and availability of heating devices. As the crude oil content in the feed increases, it is necessary to increase the number of rows of U-shaped elements or repeat the process.

A hyperbranched polymer (PMEL) was prepared using melamine as central core by a modified “one pot” method. The polymer was characterized by nuclear magnetic resonance spectroscopy (1H NMR and 13C NMR), Fourier transform infrared microscopy (FTIR), Gel permeation chromatography (GPC) and thermogravimetric analysis (TGA). Effect of standing time, temperature and concentration of PMEL on the demulsification performance of a diesel-in-water emulsion was investigated in detail. The transmittance of aqueous phase reached 91.3% if 50 mg/L of PMEL was added into an O/W emulsion for 240 min at ambient temperature. The interfacial tensions (IFT), zeta potential and microscopic analysis were further measured to explore the possible demulsifying mechanism. The current work shows that PMEL has a great application prospect in the demulsification of oil-water emulsion.

Flow assurance has been a major problem in the development of a heavy oil field. It is not common that this issue has a multiplier effect from reservoir up to processing facilities, reducing productivity and in turn, increasing financial burden. Many of oil and gas operators in Indonesia have spent a lot of capital to deal with managing complex reservoirs with severe flow assurance issues, namely high water cut, excessively viscous oil and its effect on fluid flow. Y Field has been produced for thirty years and currently produces 2800 BOPD with fluctuations in flow rate. This field is characterized by extreme oil viscosity, up to 4000 cP at surface condition, which leads to high backpressure while delivering fluid to pipeline system. This viscous oil creates unstable flow, causing unfavorable flow-pattern; slug flow to annular flow. As a result, the water and oil are not coherently arrived at the same time at receiving facilities, leading to highly frequent occurrence of oil-water slug phenomenon. Chemical injection efforts do not show significant impact toward the production, therefore an alternative approach is generated to address the production problem. A new approach is presented in this publication to reduce the occurrence of severe slugging phenomenon by performing water blending scheme during fluid transportation. The idea is based on a hypothesis that performing forced emulsion of brine and heavy oil promotes dispersion of oil into small droplets which can be carried out by injected water under relatively low velocity of fluid flow. This idea is quite interesting since it is simple to perform, by only directing produced water from water zones below hydrocarbon bearing zone or by reactivating high water cut wells to the pipeline system. In order to increase the efficiency of forced emulsion process, we approximated the minimum acceptable water cut to develop sufficient emulsion viscosity to prevent exceeding backpressure. Based on simulation using commercial software, the result shows that water cut should be maintained above 80%. A lower water cut will lead to high backpressure which will delay arrival time of oil for more than one day behind the water arrival. This result infers that one of the available solutions to handle severe slugging is by modifying water cut profile during hydrocarbon transportation. This approach gives a new insight into marginal field optimization.

This paper describes the simultaneous determination of Ba, Co, Fe, and Ni in nuts by high-resolution continuum source atomic absorption spectrometry after extraction induced by solid-oil-water emulsion breaking. Extraction yields ranged from 94.9 for Ba to 109.8% for Fe. Simultaneous measurements were carried out at secondary lines of Ba, Co, Fe, and Ni. The limits of detection and quantification were, respectively, 3.819 and 1.146 mg L−1 for Ba, 2.274 and 7.421 µg L−1 for Co, 0.095 and 0.285 mg L−1 for Fe, and 2.138 and 6.614 µg L−1 for Ni. The precision ranged from 3.1 to 4.2%, 1.5 to 8.0%, 1.6 to 6.6%, and 0.4 to 6.1% for Ba, Co, Fe and Ni, respectively. The method accuracy was assessed by recovery tests and comparison of the results obtained by the proposed extraction method with those obtained after acid digestion. Recoveries ranged from 93.5 for Ni to 104.5% for Co.

Special wetting characteristic surfaces typically combine low-surface-energy micro/nanoscale structures, and special wetting coating material applications are wide-ranging, including self-cleaning ...

Background: The advent of therapeutic proteins highlights the need for delivery systems that protect and extend the duration of its action. Ranibizumab-VEGF is one such drug used for treating wet AMD. This paper describes a facile method to sustain bioactive ranibizumab release from PLGA-based particles. Methods: Two emulsion techniques were explored namely: water-in-oil-in-water (WOW) and solid-in-oil-in-water (SOW) emulsion. The bioactivity of ranibizumab was evaluated by comparing its binding capability to VEGF, measured with ELISA to total protein measured by microBCA. Results: During the emulsion process, contact of ranibizumab with the water-oil interface is the main destabilizing factor and this can be prevented with the use of amphiphilic PVA and solid-state protein in WOW and SOW emulsion respectively. In vitro release of the ranibizumab-loaded particles indicated that a 15-day release could be achieved with SOW particles while the WOW particles generally suffered from a burst release. Released ranibizumab was capable of inhibiting endothelial cell growth indicating its retention of bioactivity. The suppression of burst release from the SOW particles was attributed to the relatively smooth surface morphology of the SOW microparticles. Conclusions: The use of SOW encapsulation in modulating ranibizumab release while maintaining their bioactivity has been highlighted. MOE (Min. of Education, S’pore)

With the improvement of environmental protection requirements, economical and efficient oily wastewater treatment methods have become a research hotspot. At the same time, the characteristics of microbubbles (large specific surface area, high zeta potential, rises slowly) make it very widely used in various fields, including the treatment of oily wastewater. There are many methods to generate microbubbles, and each method has its own applicable fields. In order to better apply microbubbles to the separation of emulsified, the experiment used a hydrocyclone to produce microbubbles. The ability of microbubbles to separate oil-water emulsions verified by the method of combining visual processing with oil content testing. The experiment shows that the hydrocyclone can generate a large number of small-sized microbubbles, and the microbubbles are stable in the emulsion for more than 30 minutes. In addition, the microbubbles can better float the emulsified oil and concentrate it on the water surface. After the treatment of microbubbles, the oily wastewater can be easily separated from oil.

This work presents the impact of fabricating pressure on the performance of ceramic membranes during the dead-end microfiltration of an oil-water emulsion. The membranes used in this study were fabricated at a pressure of 40 kN and 100 kN using the dry compaction method. The membrane characterization was done using XRD and FTIR analysis. The membrane performance was evaluated by carrying dead-end microfiltration experiments using synthetic oil-water emulsion as a feed at a trans-membrane pressure of 30 psi. The experimental results confirmed that the membrane fabricated at higher fabricating pressure (100 kN) gives better performance in terms of maximum oil rejection of 95.7% with the maximum flux of 2.04x10−3 m3/m2.s.

Oil-water separation, especially emulsion separation, has become a global challenge due to frequent oil spills and the increase in industrial oily wastewater. It is of great significance to develop a feasible and effective separation membrane to purify highly stable emulsified oily wastewater. Here, a Janus membrane that can be used to realize the on-demand separation of oil-water emulsion is prepared by spraying silicon dioxide nanoparticles modified by hexadecyltrimethoxysilane onto the stainless steel meshes. The on-demand separation of surface-stabilized emulsions whether water-in-oil or oil-in-water emulsions can be achieved by using the Janus membrane. In addition, the prepared membrane still maintains outstanding performance after 10 oil-water separation cycles and 50 sandpaper abrasion cycles. The membrane can keep hydrophobicity whether under acidic or alkaline conditions, so it can cope with various harsh environments.

Water-oil-water (oily) liquid films appear between the droplets in water-in-oil emulsions. Here we report results from systematic experiments, aimed to clarify how several important factors affect the stability and drainage of such oily films, in the presence of the nonionic oil-soluble surfactant Span 80. These results reveal that: (1) At Span 80 concentrations around the CMC, the film lifetime coincides with the duration of film drainage. When the oily films reach a critical thickness of around 40 nm, unstable thinner black spots of thickness 1 h. This effect is explained with a mass transfer of molecules between the aqueous and the oil phases which keeps the oil films out of equilibrium for a long period. These results can be used to explain and control the formation and stability of water-in-oil emulsions, in the presence of nonionic oil-soluble surfactants.

As the second most widely used artificial lift method in petroleum industry, ESPs help maintain or increase flow rates by converting kinetic energy to hydraulic pressure. During the entire life of an oilfield, water is invariably produced with crude oil. As the field ages, the water cut in production increases. Due to high shear force inside rotating ESPs, the oil-water emulsions may form, which can be stabilized by natural surfactants or fine solids existing in the crude oil. The formation of emulsions during oil production create high viscous mixture, resulting in costly problems and flow assurance issues, such as pressure drop increase and production rate lost. This paper, for the first time, proposes a new mechanistic model for predicting oil-water emulsion rheology and its effect on the boosting pressure in ESPs. The model is validated with experimental measurements with an acceptable accuracy. The new mechanistic model starts from Euler equations for centrifugal pump, and introduces a conceptual best-match flowrate QBM, at which the outlet flow direction of ESP impeller matches the designed flow direction. The mismatch of velocity directions, resulted from varying liquid flow rates, is used to derive recirculation losses. Other losses due to flow direction change, friction, and leakage flow etc. are also incorporated in the new model. QBM is obtained by matching the predicted performance curve with the catalog curve for water. With the best match flow rate determined, the ESP hydraulic head under viscous fluid flow can be calculated. For oil-water emulsions, a new rheology model based on Brinkman (1952) correlation is developed, which accounts for ESP rotational speed, stage number, and interfacial properties etc. By incorporating the rheology prediction model into mechanistic model, the ESP boosting pressure under oil-water emulsion can be obtained. The mechanistic model-predicted ESP water performance curves are found to match the catalog curves perfectly. With high-viscosity fluid flow, the model predictions of ESP boosting pressure agree well with the experimental data. For most calculation results within medium to high flow rates, the prediction error is less than 15%. With oil-water two-phase flow, the proposed rheology model predicts the effective viscosities of emulsions match testing results with 10% prediction error. The inversion points, at which the continuous phase changes from oil to water as water cut increases, are also predicted. The predictions of ESP boosting pressure under oil-water emulsion flow by coupling the mechanistic model and emulsion rheology model are comparable with experimental results.

Abstracts: Pressure driven membrane filtration has been widely adopted for oil and water recovery from oil/water emulsion. The technology offers numerous economic and environmental advantages. However, specific energy consumption remains a critical factor for its economic assessment. The specific energy consumption depends on several factors, among which is the fouling filtration period/time. Therefore, the fouling filtration time indirectly affects the overall economic viability of the system. Herein, the effect of fouling filtration time on the specific energy consumption during cross-flow filtration of 1000 ppm oil/water emulsion was evaluated. During the first 20 min of oil/water emulsion filtration, the energy consumption was found to be 0.0225 KWh/m3. While the filtration was continued to 90 min, the system requires 0.0301 KWh/m3 energy input. The tradeoff between fouling filtration time and energy consumption was found to be just before 30 mins. Suggesting that at 30 mins fouling filtration time, clean water flushing/backwashing would restore significant hydraulic performance and thus, less increase in energy input would be required. At the tradeoff point 0.0254 KWh/m3 energy was required to drive the filtration. This represents up to ∼19 % energy saving compared to the straight nonstop 90 min fouling filtration time. The overall results demonstrated that fouling filtration time affects the overall economics of cross-flow membrane filtration.

Background The article considers the state of the gas-liquid mixture in the annulus of the well, adjusts the model of oil movement from the well pump to the dynamic liquid level. A positive example of demulsificator injection from the well-head into the annulus of difficult wells at the oil field in the Republic of Bashkortostan is given. Aims and Objectives To evaluate the state of fluids in the annulus of oil producing wells in order to develop a movement model of reactants to the suction of well pump without squeezing it with well fluid or overflush fluid. To evaluate the results of the field experiment on demulsificator injection in the annulus of oil wells producing high-viscosity oil-in-water emulsion. To develop a technical solution in order to reduce associated petroleum gas separation from oil of the annulus to gas environment of the well and normalize the operation of the downhole pumping equipment. Methods The comparative analysis of the existing model of gas-liquid mixture in the annulus of the wells using its density according to the data from thermo-manometric systems is performed. The effectiveness of the demulsificator under laboratory conditions and in the course of the experimental application at the wells by its dosing into the annulus of the wells is considered. Results The most of two-way movement of the oil in the annulus of oil producing wells is adjusted. The most effective demulsification reactant for the considered wells is determined, and its application on 3 wells of the Meneuzovskoye oil field is evaluated. The necessity of oil turbulization in the annulus of the wells is proved, the fastening scheme of devices with a spiral ribbed surface in the flow column is developed.

Flaxseed gums (FG) previously reported were mostly isolated from hulls and seeds under a relatively low temperature, which led to an incomplete structural and functional understanding of the entire gum. In addition, the influences of processing conditions on the functional properties of FG have rarely been studied. In this study, FG was extracted by water at high temperature (90 °C) followed by ethanol precipitation. The physicochemical characteristics of the high temperature extracted FG were investigated, including its rheological and emulsion stabilizing properties in aqueous solution. The influences of homogenization and heating-cooling treatments on the functional properties of FG were also examined. Results indicated that FG could form a gel in aqueous solution (>0.5 wt%) at room temperature (25 °C). Mechanical shearing forces derived from homogenization (50 MPa) highly decreased the elastic properties of FG by disrupting the intermolecular network. However, the disrupted network could not be recovered by reheating (85 °C) and cooling (25 °C) processes indicating it was non-reversible. It was also observed that FG of 0.4 wt% demonstrated the best stabilizing effect on the oil/water emulsion systems for the appropriate viscosity and weak-gel properties. The study aims to provide a full understanding of the rheological and emulsifying properties of high temperature extracted FG under different treating conditions with an intent to promote its application in the food and non-food industries.

The process of synthesis of 1st-, 2nd- and 3rd-generation dendritic polyamidoamines (PAMAM), using ammonia and ethylenediamine, is described. It is shown that the oil drops disintegration rate constant and the degree of breakdown of a stable oil–water emulsion increase with each subsequent generation of the dendrimer and with its increasing concentration. The maximally attained degree of separation of water containing 68 mg/L of oil was 84.6% with the addition of 20 mg/L of 3rd-generation PAMAM. The demulsification mechanism is shown to be associated with the spherical shape of the dendritic PAMAM macromolecules and the presence of a large number of polar amino functional groups on the surface of these spheres.

The procedure of emulsion preparation with hydrocolloids which are stabilizer-emulsifiers, namely gum-arabic and starch, was updated by introducing new technological parameters, such as oil : aqueous phase ratio, sequence and parameters of ingredients introduction, parameters of pre-emulsion preparation and homogenization. The food emulsion samples were investigated using different amounts of gum-arabic and starch at constant amount of oil phase and samples with variable amount of oil phase and constant amount of a stabilizer. The optimum ratio between aqueous stabilizer and oil phase is characterized by maximum number of emulsion particles with the size under 1 micron. Удосконалено спосіб приготування емульсій з гідроколоїдами, які є стабілізаторами-емульгаторами, – гуміарабіком та крохмалем – внаслідок введення нових технологічних показників (співвідношення оливної та водної фази, послідовність та параметри введення інгредієнтів у відповідні фази, параметри приготування преемульсії та процесу гомогенізації). Досліджено зразки харчових емульсій з використанням різної кількості гуміарабіку або крохмалю як стабілізатора (при сталій кількості оливної фази) та зразки емульсій зі змінною кількістю оливної фази і постійною кількістю стабілізатора. Встановлено, що оптимальне співвідношення водного стабілізатора та оливної фази емульсії характеризується отриманням максимальної кількості частинок емульсії розміром до 1 мікрона.

A new multifunctional KGM/PDA/PVDF composite membrane was successfully prepared via facile nonsolvent induced phase inversion method. Here, the KGM component consisted of numerous covalent bonds, which could improve the corrosion resistance of membrane materials. The dopamine, as a natural “glue” between PVDF substantial and KGM, is capable of integrating different materials together suitably. The as-prepared membrane possessed superior superhydrophilic/underwater superoleophobic property, great corrosion resistance and antifouling property. The separation efficiency was as high as 99.01%, and could stay relatively stable even in the acid, alkali or high salty environment. Additionally, the membrane had great regeneration performance and could keep stable after 15 cyclic separation, which was appropriate for efficient various oil–water separation process. Moreover, the composite membrane could also effectively separate dyes in different environments and the efficiencies were all more than 91%. All in all, the multifunctional composite membrane with facile preparation method might provide a promising strategy and significant theoretical basis for the efficient separation of oil–water emulsions and dyes.

The thickening agents are an important part of the cosmetic formulation, offering an opportunity not only to regulate the product viscosity, but also to improve its stability. But, the way to use them and the impact of these natural ingredients on the qualities of the finished product are not always assessed. In this work, a new multifunctional glucomannan-based blend has been evaluated, the aim was to study its influence on the qualities of an oil/water emulsion. To get a rational understanding of this factor, an experimental design approach was adopted. An Optimal design optimized for a second-degree model (Quadratic) with only 12 runs and 1 repeated point was implemented. From the formulation, three ingredients concentrations varied as following; the thickener, a glucomannan-based blend, from 0.6% to 1.2%, one emollient from 3% to 7% and the emulsifier from 3% to 6%. The emulsion was prepared at 70°C and the thickener was added at 50°C. Viscosity measurement, droplets size and stability were analyzed 48 hours following the preparation. In the final emulsions, in terms of viscosity and stability to centrifugation, the glucomannan-based blend was is the parameter with the strongest impact. As for the droplets size, it was impacted the most, thus in a smaller extend, by the emulsifier concentration. Moreover, a synergistic effect between the emulsifier and thickener was monitored on the droplets size parameter while the concentration of squalene proved little influence. Finally, the optimal concentration of glucomannan-based blend to ensure system stability was determined at 1.2%. In conclusion, conducting an Optimal design allowed to model the effect of the thickener in formulation as well as the interactions between the monitored ingredients.