Crude Oil Emulsions Research Articles

Demulsification efficiency of the leave extract from African blackwood (Delbergia melanoxylon)

The demulsification efficiency of the leave extract from African Blackwood (Delbergia Melanoxylon) was determined using the bottle test method. Methanol, n-heptane and distilled water were used as extraction solvents respectively to extract the active ingredients of the leave. A 200 ml crude oil emulsion obtained from Niger Delta area Nigeria was introduced into six (6) calibrated 500 ml Teflon-stoppered bottles respectively, the leave extract in the solvent was introduced into each of the bottles as a demulsifier at concentrations of 50, 100, 150, 200 and 250 ppm with the sixth bottle left as control (without demulsifier). All the bottles were immersed in a water bath of 60 0C after mixing properly with a mechanical laboratory mixer and left for an hour. After an initial 5 minutes, the percentage of water separated in each bottle was recorded after 10 minutes. Bottle test was also carried out using a synthetic demulsifier (DXO77) on the same crude oil. Results obtained shows that the leave extract using methanol had the highest demulsification efficiency separating 50.5 % water from the crude after 60 minutes with a demulsifier concentration of 250 ppm. A 250 ppm of the synthetic demulsifier (DXO77) separated 51.0% of water from the crude after 60 minutes. The leave extract using n-heptane and distilled water separated 40.5 % and 32.5% water from the crude after 60 minutes at demulsifier concentrations of 250 ppm respectively. There is a consistency in the percentage of water from the crude within the last 15 minutes indicating that the separated water in the crude has reached its threshold, further increase in the demulsifier concentration at this point could lead to emulsification. The demulsification efficiency of plant extracts such as African Blackwood (Delbergia Melanoxylon) are influenced by the characteristics of the extraction solvent such as solvating power and extraction capacity.

Research and Application Progress of Crude Oil Demulsification Technology

The extraction and collection of crude oil will result in the formation of numerous complex emulsions, which will not only decrease crude oil production, raise the cost of extraction and storage, and worsen pipeline equipment loss, but also seriously pollute the environment because the oil in the emulsion can fill soil pores, lower the soil’s permeability to air and water, and create an oil film on the water’s surface to prevent air–water contact. At present, a variety of demulsification technologies have been developed, such as physical, chemical, biological and other new emulsion breaking techniques, but due to the large content of colloid and asphaltene in many crude oils, resulting in the increased stability of their emulsions and oil–water interfacial tension, interfacial film, interfacial charge, crude oil viscosity, dispersion, and natural surfactants have an impact on the stability of crude oil emulsions. Therefore, the development of efficient, widely applicable, and environmentally friendly demulsification technologies for crude oil emulsions remains an important research direction in the field of crude oil development and application. This paper will start from the formation, classification and hazards of crude oil emulsion, and comprehensively summarize the development and application of demulsification technologies of crude oil emulsion. The demulsification mechanism of crude oil emulsion is further analyzed, and the problems of crude oil demulsification are pointed out, so as to provide a theoretical basis and technical support for the development and application of crude oil demulsification technology in the future.

Research on Apparent Viscosity Variation of Water-in-Oil Waxy Crude Oil Emulsions Induced by a Magnetic Field

Research on Apparent Viscosity Variation of Water-in-Oil Waxy Crude Oil Emulsions Induced by a Magnetic Field

Preparation of novel nanoparticle demulsifier and its demulsification for surfactant-stabilized crude oil emulison

The application of nanoparticle (NP) demulsifiers in processing the emulsified crude oil production fluid is of great significance for improving production efficiency and reducing energy consumption in crude oil extraction. In this work, a novel NP demulsifier (PPA@KAO) was prepared by chemically modifying the mineral kaolinite (KAO) nanoparticles using γ-Methacryloyl propyltrimethoxysilane (MPS) and polyether-polyquaternium (PPA). The morphology and structure of the PPA@KAO demulsifiers were characterized by FT-IR, SEM, TG, XPS and Zeta potential. The contact angle measurements, interfacial tension (IFT) characterization, and the distribution of nanoparticles in the oil-water phase showed that PPA@KAO have good amphiphilicity and interfacial activity. The demulsification performance of PPA@KAO demulsifiers for a sodium dodecyl benzene sulfonate (SDBS) stabilized crude oil emulsion was studied with bottle method. It was found that the oil-water separation could be completed within 20 min, with a demulsification efficiency of 96.75 % at a dosage of 3 g L−1，pH of 6 and temperature of 30°C. Such a result indicates that the PPA@KAO NP demulsifier can achieve rapid and efficient demulsification for the surfactant-stabilized crude oil emulsion at room temperature. The demulsification mechanism of PPA@KAO for the SDBS-stabilized crude oil emulsion was well revealed, which provides an important synthetic strategy of how obtaining an effective NP demulsifiers by regulating the amphiphilicity and surface functional groups of the nanoparticles.

Enhancing dehydration/desalting efficiency of crude oil emulsions through experimental and computational insights

The formation of unwanted oil emulsions during producing, transporting, and processing crude oils is a major challenging issue, which causes serious technical problems, and subsequently huge financial losses. The present work delves into an optimization study focused on water separation from crude oil emulsions. The separation performance was initially assessed in static conditions through bottle tests, followed by a thorough investigation in dynamic conditions on an electrostatic desalting pilot plant under various conditions of the main operating parameters: temperature, oil space velocity, wash water ratio, and demulsifier concentration. The design of experiments and optimization of the process were performed by Central-Composite-Design of Response-Surface-Methodology (CCD-RSM). The effectiveness of the separation process has been analyzed by evaluating the Water-Removal-Efficiency (WRE) and Salt-Removal-Efficiency (SRE). The obtained results demonstrated that the used demulsifier was found to be extremely efficient and to have the greatest impact on the dehydration efficiency (F-value = 434.56). In addition, the sensitivity analysis indicated that the dehydration/desalting process is also very sensitive to the oil space velocity and wash water ratio while having less sensitivity to changes in the temperature. Furthermore, the process optimization indicated that the highest efficiency of simultaneous removal of water and salt from crude oil (WRE = 94.54 % and SRE = 97.23 %) was observed at optimal conditions of 19.5 ppm demulsifier concentration, 125 °C temperature, 1 1/h oil space velocity, and 6 vol% wash water ratio.

STUDY ON THE INFLUENCING FACTORS OF DEMULSIFIER ON THE OIL-WATER INTERFACE VISCOELASTICITY

Water flooding is a commonly used development method in oilfields, and the water cut of the output fluid of oil wells gradually increases with the increase of injected water in water wells. Due to the presence of natural surfactants such as gum, asphaltene and organic acid in crude oil, it is easy to form a high strength viscoelastic oilwater interfacial film and a stable emulsion. To facilitate the storage and transportation of crude oil, it is necessary to demulsify the crude oil emulsion. In this paper, the CQ crude oil was taken as the research object, and the effects of demulsifier type, concentration, demulsifier temperature and oil-water properties on the viscoelasticity of oil-water interfacial film were investigated by using rheometer and then the demulsification mechanism was explored. The results show that the lower the interfacial film strength, the better the demulsifier. In addition, with the increase of demulsifier concentration and temperature, the oil-water interfacial viscoelasticity decreases and the interfacial film strength further decreases. In general, the demulsification effect will be significantly improved with the increase of demulsifier concentration and temperature, and the dehydration effect will be better. The research results can provide theoretical guidance for the field application of demulsification.

Amphiphilic Ionic Liquids for Chemical Separation of Crude Oil Emulsions

AbstractThis work aims to synthesize novel amphiphilic ionic liquids (AILs), AH‐PM, and AD‐PM as well as apply them to chemically demulsifying crude oil emulsions. Two AILs containing different long alkyl chains were synthesized and characterized using several techniques. The surface and interfacial indicated AILs’ surface activity and ability to form micelles. For that, the demulsification efficacy (DE) of these AILs was explored using different factors affecting, e.g., AIL dose, settling time (ST), water content, and temperature. The results indicated that the AIL hydrophobicity resulting from the longer alkyl chain could improve AIL DE. Moreover, increased AIL dose, ST, water content, and temperature improved DE.

Advancing green technology: demulsifier preparation and evaluation for crude oil emulsion treatment using corn oil

Globally, oil production has steadily increased which causes a rise in the coproduction of oil and water emulsions. These emulsions pose significant challenges in transportation and the oil refinery industry, causing high-pressure drops and corrosion problems due to chlorides in the water. Despite advancements in renewable energy, crude oil remains a primary energy source. The crude oil industry faces numerous challenges, including cost emulsion issues. This study developed a corn oil bio-demulsifier (MFK). A unique demulsifier was tested using FTIR, GC-MS, and TGA. Using the bottle test method, the produced demulsifier MFK was tested with Basrah oil and East Baghdad S1 oil. The emulsion-breaking processes have been studied under several factors, such as settling time, dosage, temperature, pH, water content, and mixing time after demulsifier addition. At 2000 ppm Basrah oil, water separation efficiency reached 75%. For East Baghdad S1 oil, the highest separation result was 43.3% at 4000ppm, after 5 h of settling time at 70°C, with a 30/70 water-to-oil ratio. When studying the pH, the best water separation rate was 86.5% at a pH of 10. The best water content was 92% when the water-to-oil ratio was 50/50, and the best demulsifier mixing time with the emulsion was 2 min with a separation rate of 74.5%. When mixing was increased, undesirable results occurred. This study demonstrated that biodemulsifiers may replace conventional biodemulsifiers in early units while reducing environmental and economic impacts with further study and development.

Multiband MgAl0.05Ge0.95O3:0.3%Pr3+ Persistent Phosphor as Efficient Tracers in Crude Oil Emulsions.

The use of fluorescent nanoparticles (NPs) for tracing purposes in oilfields encounters challenges due to background interferences under constant external excitation caused by organic residues present in crude oil. This results in insufficient sensitivity and lower tracer detection limits in the crude oil/water emulsions. In this study, we present the synthesis of persistent luminescent NPs, showcasing their remarkable application as tracers in crude oil. The multiband MgAl0.05Ge0.95O3:0.3%Pr3+ persistent NPs were synthesized via the sol-gel method. Through meticulous experimentation and analysis, our study unveils a novel avenue for efficient and lasting traceability in crude oil. The synthesized NPs emit light across the visible, near-infrared, and shortwave infrared regions, allowing for versatile detection. The unique luminescent properties of these NPs, particularly their ability to persist in emitting light without a continuous external excitation, enable their effective use as tracers in crude oil/water emulsions where background fluorescence typically poses a significant challenge. By employing these persistent NPs in background fluorescence-free conditions, we achieve ultrahigh sensitivity in detecting these NPs in crude oil. Our research reveals that the doping of Al3+ ions significantly enhances both the afterglow intensity of MgGeO3:0.3%Pr3+ phosphor and the afterglow decay time of Pr3+ emission. This characteristic enables the re-excitation of MgAl0.05G0.95O:0.3%Pr3+ NPs within the emulsion, allowing for repeated spectral and imaging acquisition. This high sensitivity not only facilitates precise imaging of NPs in crude oil but also enables long-term monitoring in real-time, offering valuable insights for oilfield operations.

The influence of asphaltene and resin on the stability of crude oil emulsion and its demulsification mechanism

Currently, the effects of natural emulsifiers such as resin and asphaltene in crude oil on the stabilities of the emulsions as well as the demulsification mechanism of oil–water separation are still not well understood. In this study, the changes in oil–water wetting angle and interfacial tension (IFT) of crude oil emulsions were compared by extracting resin and asphaltene from crude oil to expound the effects of resin and asphaltene on the stabilities of crude oil emulsions. Meanwhile, the mechanism of demulsifier was discussed based on the competitive adsorption test of demulsifier and asphaltene. It was found that asphaltene was the main emulsifier in the process of oil–water emulsification. With the increase of asphaltene contents, the oil–water wetting angle decreased from 72.9° to 37°, the IFT decreased from 27.13 mN/m to 11.23 mN/m, and the emulsion droplet decreased from 10.3 mm to 1 mm. Demulsifier mainly reduced the stability of crude oil emulsion and realized oil–water separation by the replacement of the interface film-forming substances, the reduction of the oil–water interface tension, and the neutralization of interface charges. The results provide useful information for the demulsification and oil removal of oil-bearing wastewater emulsion.

Facile preparation of multi-functionalized zwitterionic surfactants for the separation of water in Arabian heavy crude oil emulsions

We report an easy process to prepare new anionic and zwitterionic surfactants to break water in Arabian heavy crude oil emulsions (W/O) with different compositions (10/90, 30/70 and 50/50 vol%). Surfactants were prepared in only two stages using simple methodology. Diethylenetriamine was interacted with three moles of glycidyl 4-nonyl ether followed by the interaction with 3 and 8 mol of 1,3-propanesultone to yield TNDTS-3 and TNDTS-8 respectively. FTIR and NMR spectroscopies were carried out to substantiate the chemical structures of surfactants. Relative solubility number (RSN), surface activity and solubility properties were determined. Demulsification efficiencies and interfacial tension (IFT) of the prepared surfactants were investigated. Our findings demonstrated that increasing propyl sulfonate groups in the surfactant structure improved water solubility, IFT activity and demulsification efficiency. TNDTS-8 achieved 100 % demulsification activities in all W/O emulsions (10/90, 30/70 and 50/50 vol%).

The Effect of Hydrophobic Modified Block Copolymers on Water-Oil Interfacial Properties and the Demulsification of Crude Oil Emulsions.

The demulsification effect of three types of block copolymers, BP123, BPF123, and H123, with the same PEO and PPO segments but different hydrophobic modification groups on crude oil emulsions and the properties of oil-water interfaces were investigated using demulsification experiments, an interfacial tensiometer, and surface viscoelastic and zeta potential instruments in this paper. The results showed that the hydrophobic modification group of the block copolymers had great effects on the demulsification performance. The H123 block copolymers with the strongest hydrophobicity had the best demulsification effect on the crude oil emulsions. The properties of the oil-water interfaces indicated that the modified block copolymers achieved the demulsification of crude oil emulsions by reducing the strength of the oil-water interfacial film and the interfacial tension.

Advancing oil-water separation: Design and efficiency of amphiphilic hyperbranched demulsifiers

Hypothesis: An innovative strategy for designing high-performance demulsifiers is proposed. It hypothesizes that integrating mesoscopic molecular simulations with macroscopic physicochemical experiments can enhance the understanding and effectiveness of demulsifiers. Specifically, it is suggested that amphiphilic hyperbranched polyethyleneimine (CHPEI) could act as an efficient demulsifier in oil–water systems, with its performance influenced by its adsorption behaviors at the oil–water interface and its ability to disrupt asphaltene-resin aggregates.Experiments: Several coarse-grained models of oil–water systems, with CHPEI, are constructed using dissipative particle dynamics (DPD) simulation. Following the insights gained from the simulations, a series of CHPEI-based demulsifiers are designed and synthesized. Demulsification experiments are conducted on both simulated and crude oil emulsions, with the process monitored using laser scanning confocal microscopy. Additionally, adsorption kinetics and small angle X-ray scattering are employed to reveal the inherent structural characteristics of CHPEI demulsifiers.Findings: CHPEI demonstrates over 96.7 % demulsification efficiency in high acid-alkali-salt systems and maintains its performance even after multiple reuse cycles. The simulations and macroscopic experiments collectively elucidate that the effectiveness of a demulsifier is largely dependent on its molecular weight and the balance of hydrophilic and hydrophobic groups. These factors are crucial in providing sufficient interfacial active functional groups while avoiding adsorption sites for other surfactants. Collaborative efforts between DPD simulation and macroscopic measurements deepen the understanding of how demulsifiers can improve oil–water separation efficiency in emulsion treatment.

Effect of silica nanoparticles on crude oil emulsions stabilized by a natural surfactant from Fenugreek Seeds and polyacrylamide for subsurface oil mobilization applications

Emulsions represent a sustainable method for subsurface resource recovery due to their superior performance in pore plugging, mobility control and interfacial tension reduction. However, the stability of emulsion plays a vital role in determining the success of field implementation. In this work, a novel formulation is reported for emulsions wherein they have been stabilized by natural surfactant extracted from fenugreek seed. In this work, two emulsion systems are reported, that is surfactant polymer and nanoparticle-surfactant-polymer emulsion. Surfactant-polymer emulsions are stabilized by natural surfactant whereas nanoparticle-surfactant-polymer emulsion are stabilized in presence of nanoparticle and natural surfactant. Both the emulsions exhibit shear thinning profile as observed from rheological studies. Nanoparticle-surfactant-polymer emulsions were found to be thermally stable than that of Surfactant-polymer emulsions as evident from microscopic and rheological studies. An increase in temperature has the unfavorable impact on surfactant-polymer emulsion as huge drop in viscosity profile was observed. The viscosity profiles of nanoparticle-surfactant-polymer emulsions were found to be best fitted by the Krieger-Dougherty model with the value of coefficient correlation R2 = 0.99. The contact angle studies showed that NSP solution can reduce the contact angle to much lower value, which is 111˚ to 30˚ whereas surfactant-polymer solution was able to reduce from 116˚ to 57˚ only. Adsorption of silica nanoparticle was also observed in presence of sandstone and decrease in 27.32 % of peak absorbance was observed in span of 20 days. Therefore, finding of the study indicates that nanoparticle-surfactant-polymer emulsions has potential to perform better than surfactant-polymer emulsions, even at elevated temperature, and can be a better and cost-effective alternative to the conventional emulsions used in oilfield applications.

Treating produced water - crude oil emulsion using concentric packed UV- bioelectrochemical cell (CPUBEC)

This research paper comes in the context of the growing global scientific path to develop clean renewable energy production methods that are commensurate with the required environmental standards, reduce carbon emissions, and treat pollutants in the water produced with the production of crude oil from oil fields, which are large quantities and are constantly increasing with the growing global demand for oil and gas. A bioelectrochemical cell was manufactured from available capacitive materials (GQDs/TiO2) with biofilm spread in the parts that are not directly exposed to UV ray in an innovative installation consisting of a cylindrical shell with spherical packing anode and a cathode in the middle of membrane that separates the tow electrodes. Both electrodes are arranged in a Pyrex pot and connected to external resistance. The packed cell (with and without uv-ray) performance was compared with unpacked cell to determined the effect of the packing and UV ray by studying the efficiency of removing pollutants TPH and COD. the best results in the packed cell with UV ray as follows:97.1 %, 97 % respectively, while the best results obtained in the case of using an unpacked cell was 86.6 %, 84.8 %. the change in the pH during the operating cycle was also studied and it was found that the change in the packed cell was slightly greater than the change in the unpacked cell as a result of the complex interactive on the surface of the anode. The highest current density produced was 1316 mA/m2 on the fifth day in packed cell and presence of UV ray.

Demulsification of water in crude oil emulsions via phosphonium-based ionic liquids: Statistical modeling and optimization

In the present study, the performance of two ionic liquids namely Tetrabutylphosphonium bromide (TBPB) and Tetraoctylphosphonium bromide (TOPB) as the demulsifying compounds are investigated in the demulsification operation of water in light and medium crude oil emulsions for the first time. The response surface methodology (RSM) is employed to evaluate the impact of temperature, pH, water content, demulsifier concentration, and settling time on the demulsification efficiencies of studied demulsifiers. In order to design the requisite experiments and optimize the effective factors on the water removal efficiency, the central composite design (CCD) is applied. To determine the optimal conditions of input parameters, four exact models are created by utilizing the responses of 184 experiments to predict the demulsification efficiencies of two demulsifiers for two types of crude oils based on statistical tests of different models using the analysis of variance (ANOVA). High R2 coefficient values imply that the developed models could reproduce the experimental results of the studied demulsifiers appropriately. At the optimal conditions, the water in light and medium crude oil emulsions are completely broken in the samples containing TOPB. Moreover, TBPB agent presents high and acceptable demulsification efficiencies for both types of crude oils at the optimal values of process parameters i.e. 98.078% and 96.025% for light and medium crude oil emulsions, respectively. The superior demulsification performance of TOPB with respect to TBPB can be ascribed to the longer alkyl chain length of TOPB.

Emulsification characteristics of crude oil with a high content of heavy components and its emulsification mechanism in porous media

There are occurrences of crude oil emulsification following the fracturing shut-in wells in the Jimushar, but the emulsification characteristics and mechanism remain unclear. In this study, the low-field nuclear magnetic resonance technique and visual microdisplacement tests are employed to investigate the emulsification characteristics of crude oil, along with its emulsification mechanism in porous media. Experimental results revealed that the heavy components (asphaltene and resin) enhance crude oil emulsification by increasing the viscous force of water droplets in the oil phase, affecting the size and stability of small water droplets in the oil phase. In the process of flowing through pore throats, emulsions are formed primarily by stretching and snap-off action, with stretching preferring to form smaller droplet-size emulsions, while snap-off results in the division of larger oil droplets into two smaller ones. The primary factors causing a large oil droplet to be stretched into smaller droplets include changes in the composition of the oil droplet, external tension, and the duration of these forces acting on the droplet. Capillary forces can emulsify crude oil and water at the pore scale, resulting in a reduction of the absorption rate. However, this rate can be restored when the capillary forces are strong enough for the water phase to penetrate and break through the emulsified layer. This study offers valuable insights into understanding the adaptability of the emulsification flooding mechanism.

Dynamic Deposition of PDA on a Hollow Fiber Ceramic Membrane for Oily Water Treatment.

Ceramic membranes have been widely used in oil-water treatment; however, membrane fouling remains a challenge that must be addressed to improve the process feasibility. A thin layer of polydopamine (PDA) was dynamically deposited on the surface of the alumina hollow fiber membranes to reduce oil adhesion. The PDA-alumina membranes were characterized by using SEM-EDS, AFM, and water contact angle measurements. The performance of the modified membranes was evaluated using synthetic crude oil emulsions (100 mg·L-1) in a crossflow system. Membranes modified with PDA exhibited 97% oil rejection, and a stabilized permeate flux of 463 L·h-1·m-2 with a relative flux reduction of 60% and a flux recovery ratio of 75% was observed after cleaning, indicating lower oil adhesion and better fouling reversibility. The most predominant fouling mechanism for the modified membranes seems to be cake filtration because of the reduction in pore size due to the deposition of the PDA layer.

Cucurbit[7]uril-Modified Nano SiO2 for Efficient Separation of Crude Oil Emulsions: Properties and Demulsification Mechanism.

Demulsification of crude oil emulsion is an obvious problem in the whole of petroleum engineering, which needs to be dealt with urgently. In this paper, a supramolecular material Cucurbit[7]uril-SiO2 (CB-SiO2) synthesized with excellent demulsification efficiency (DE) on O/W emulsion was synthesized by a simple thermal synthesis method. The microscopic morphology and structure were investigated through modern characterization techniques. Furthermore, its stability, dynamic interfacial tension (IFT), and wettability (three-phase contact angle (CA)) were systematically investigated, and the demulsification efficiency of different conditions on crude oil emulsion was also investigated. Reassuringly, these results showed that when the temperature was 70 °C, the demulsification dosage was close to 600 mg/L and remained unchanged for 90 min; the demulsification efficiency is 2.2 times compared with the unmodified material, up to 93.63%. In addition, a plausible demulsification mechanism was proposed, which is that CB-SiO2 can adsorb and disrupt the oil-water interface, leading to oil-water separation and promoting demulsification. It is a promising demulsification material for the oil industry demulsification.

Efficient Demulsification of Crude Oil Emulsion Using Novel Sugar-based Surfactant.

This study aimed to synthesize ecofriendly and low-cost surfactant-based sugar, HA-ST, under mild conditions and a short route via an opening ring of hexadecylsuccinic anhydride (HA) using starch (ST). HA-ST's chemical structure, thermal behavior, and surface activity were evaluated using Fourier Transform Infrared (FTIR) spectroscopy, thermogravimetric analysis, and a pendant drop technique. The results indicated HA-ST formation, thermal stability, and surface activity. HA-ST's green character, low cost, and surface activity recommended its use as a demulsifier for crude oil emulsions at different affecting parameters such as temperature, seawater ratio (SR), demulsifier concentration, demulsification time (DT), and pH. HA-ST demulsification efficiency (DE) was evaluated and compared with a commercial demulsifier (CD). The results showed improved HA-ST's DE with rising temperature, SR, demulsifier concentration, DT, and pH. The DE of HAST reached 100% at 50% of SR and 250 ppm of demulsifier concentration; the same results were obtained using CD. In contrast, HA-ST gave relatively lower DE at low SR (10%) with a value of 70% than the obtained using CD with a value of 75%. The green character, low cost, and DE of HA-ST make it suitable for demulsifying crude oil emulsions, especially those containing more than 30% seawater, compared with CD, which commonly contains two or more traditional surfactants.