Types Of Crude Oil Research Articles

Prices

Assessed or estimated prices and values for the major types of crude oils traded on spot markets. Updated on a monthly basis.Official sales prices (except as otherwise noted) and are generally market‐related, subject in some cases to retroactive adjustment. Updated on a monthly basis.

Sudan'daki Bir Rafineride Kullanılan İki Farklı Ham Petrol Türünün Karşılaştırmalı Yaşam Döngüsü Değerlendirmesi

Climate change, caused primarily by fossil fuels used for meeting the increasing energy demand, has become a global concern since the last decade. One of the most important sectors contributing to this demand is transport fuel production. Oil refining is the hotspot for life cycle environmental burdens of all transport fuel types. To respond to this global challenge, all parties need to work in an identical pattern, i.e., socially appropriate, technically feasible, economically sustainable, and environmentally friendly. Specifically, the oil refining industry uses vast amounts of raw materials and creates considerable waste that needs to be processed, mainly at refinery sites. In this study, we compare two different types of crude oil used in Sudan refineries, namely X and Y blend crude oil, in terms of environmental impacts. A detailed Life Cycle Assessment (LCA) defined by the ISO14040/14044 frameworks carried out via SimaPro software v.8.1.1.16. Both midpoint and endpoint approaches were adopted for the ReCiPe impact assessment method. Based on the selected midpoint impact categories, i.e., climate change, ozone depletion, human toxicity, and terrestrial acidification, the X crude oil impact scores were 282.7 kg CO2 eq, 2.45E-06 kg CFC-11 eq, 1.05 kg 1,4-DB eq, and 0.145 kg SO2 eq while the Y crude oil scores were 265.9 kg CO2 eq, 1.58E-06 kg CFC-11 eq, 0.735 kg 1,4-DB eq, and 0.095 kg SO2 eq, respectively. From an endpoint approach considering the representative single scores, overall impacts for the X and Y crude oil created an environmental load output of 13.8 and 12.7 Pt, respectively. As expected, both types of crude oil had a direct impact on the environment, where crude oil Y was found to have 10% less impact than crude oil X.

Interfacial tension of acidic heavy crude oil type and dolomite surface wettability: salinity and nanoparticles impact

ABSTRACT Waterflooding is the widespread method for displacing the residual oil toward well production because of its accessibility and low cost. Currently, several oil-rich countries are investigating to untangle the current shortcomings to make waterflooding method efficacious more. On the other side, salinity composition has been considered in enhanced oil recovery (EOR) for better sweep efficiency and has captured great interest for EOR techniques. In this study, oil–water interfacial tension (IFT) was measured between acidic heavy crude oil (AHCO) and brine solutions of MgCl2, CaCl2, KCl, NaCl, and Na2SO4 in various concentrations from 0.1 to 1 M and analyzed to obtain the highest IFT reduction. Moreover, the effects of AHCO and water composition on initial wettability of carbonate rock were investigated. The variations of surface properties of dolomite rock samples were investigated by contact angle (CA) measurements after aging thin sections in oil and brine. In addition, silica nanoparticles (NPs) as the IFT reducer and wettability alteration affordable agent were examined to compare their effects on salinity. The lowest IFT value between AHCO and brine solutions was reported 6.5 mN/m by magnesium chloride at 1 M concentration. Likewise, the highest impact on wettability alteration from oil-wet system (137.37◦) to strongly water-wet system (30.79◦) was obtained by magnesium chloride at 1 M concentration as well. Moreover, the application of silica NPs based on different salinity showed an inconspicuous impact in this study.

Spillovers and directional predictability between international energy commodities and their implications for optimal portfolio and hedging

This study sheds a new light on the dependence and the directional predictability between eight major energy price returns, using the Cross-Quantilogram (CQ) and the Partial CQ (PCQ) analysis. The energy prices cover the time series for the U.S. natural gas and seven internationally traded crude oil types. The results reveal a significant directional predictability running from most of energy commodities returns to the OPEC basket and the very light Tapis crude oil returns. However, the quantile predictability in both directions is enabled only for the relations between the light Brent and the light WTI, and between the OPEC basket and the Malaysian Tapis. The time-varying predictability analysis reveals that there is a significant upper quantile dependence between these international energy commodities. Finally, we find that the TAPIS can be a good hedging vehicle for other energy markets. These findings may be instructive for both policymakers (in terms of financial stability) and market participants (in terms of performance).

Prices

Assessed or estimated prices and values for the major types of crude oils traded on spot markets. Updated on a monthly basis.Official sales prices (except as otherwise noted) and are generally market‐related, subject in some cases to retroactive adjustment. Updated on a monthly basis.

Utilizing Attapulgite as Anti-Spill Liners of Crude Oil

The efficiency of attapulgite liners as anti-seepage for crude oil is examined. Consideration is given to the potential use of raw attapulgite and mixture attapulgite with prairie hay and coconut husk as liners to prevent crude oil seepage. Attapulgite clay used in this study was brought from Injana formation /Western Desert of Iraq. Two types of Crude oil brought from Iraqi oil fields were used in experiments; heavy crude oil from East-Baghdad oil field and light crude oil from Nassiriya oil field. Initially the basic properties of attapulgite and crude oils were determined. The attapulgite clay was subjected to mineralogical, chemical and scanning electron microscope analyses. Raw Attapulgite 150µm, 75µm, and 53µm were tested as anti-seepage liners for heavy and light crude oil. Experiments showed that raw attapulgite liners 53µm and 75µm are good in terms of retention and prevention of seepage so they can be used as the main layer to impede the flow of heavy crude oil. Raw attapulgite150µm could not be used as a liner to impede the flow of crude oil. This type of liner is totally inefficient for heavy and light crude oil. Adding prairie hay to attapulgite 150µm gives a good barrier medium that retains heavy crude oil and prevents it from seepage as long as possible. Raw attapulgite liners failed to prevent light crude oil seepage whereas the partial substitution of attapulgite by prairie hay or coconut enhanced the performance of the liner. Moreover, the addition of prairie hay with coconut to attapulgite enhanced the performance of the liner to a greater extent compared to raw attapulgite liners and mixture liner attapulgite with prairie hay.

Application of Rheo-optic In Situ Measurement Technology to Study Waxy Crude Oil Rheology

The micromechanism of waxy crude oil gelling is the interaction between wax crystals to form a certain intensity flocculation structure, which significantly increases the cost of production and transmission. In this paper, rheo-optic in situ measurement technology is applied to the rheological study of waxy crude oil for the first time and also to the rheological response of typical waxy crude oil to thermal history, the micromechanism of shear-thinning, and the dynamic behavior of wax crystal. Through the new experimental technique and analysis method, it is found that two types of wax crystals can be formed under certain thermal historical conditions, which have opposite performances in microscopic morphology, mechanic properties, and flocculation tendency, and the change of its proportion in crude oil is the root cause of the initial cooling temperature affecting the fluency of waxed crude oil. It was found that the microscopic behavior of waxy crude oil with the increase of shear rate went through the following whole process: the waxy crude oil system changes from static to dynamic, the wax crystal flocculation network undergoes deformation, cracks, and ruptures, and wax crystal aggregates break, small aggregates orient along the flow field, and small aggregates continues to deform and break. When the shear rate is below 5 s–1, the crack of the flocculation structure plays a leading role. It is only after the shear rate exceeds 5 s–1 that the deformation of the wax crystal and its flocs begins to function. Furthermore, according to the microscopic images of the wax crystals motion sequence, the micromorphology of different types of flocs and the dynamic behaviors under shearing are systematically analyzed by dynamic micro-object capture technology.

Tail risk connectedness in the refined petroleum market: A first look at the impact of the COVID-19 pandemic

This study provides a novel framework for analysing systematic tail risk transmission mechanisms by combining the Conditional Autoregressive Value-at-Risk (CAViaR) model with the recently developed Time-Varying Parameter Vector Autoregressive (TVP-VAR) based connectedness approach. We estimate dynamic spillovers across two crude oil (Brent and WTI) and four refined petroleum product (gasoline, heating oil, jet fuel and propane) prices from January, 17, 1997 to December 11, 2020. Results show that, both heating oil and kerosene are persistent net transmitters of shocks, signifying the important role of liquidity in the relevant markets. In addition, the role of either crude oil type appears to shift around 2009 following developments in the energy market. Overall, our findings suggest that, total connectedness are positively affected by major crisis episodes and that the recent COVID-19 pandemic appears to have the potential to propel both tail risk and exposure to losses to levels akin to those of the Global Financial Crisis of 2007–2008.

Prices

Assessed or estimated prices and values for the major types of crude oils traded on spot markets. Updated on a monthly basis.Official sales prices (except as otherwise noted) and are generally market‐related, subject in some cases to retroactive adjustment. Updated on a monthly basis.

Analysis of factors affecting the efficiency of Jatropha curcas oil as an asphaltene stabiliser

The effect of temperature and applied dose on the efficiency of Jatropha curcas seed oil as an asphaltene stabiliser was studied. Two crude oil samples (light and medium) were used. J. curcas oil was subjected to heating at 100, 150 and 170 °C for 24 h with an unheated sample (25 °C) and applied at doses of 2, 4, 6, and 8 μL in 10 ml of sample. The asphaltene instability index (AII) was determined as the ratio between the amount in ml of n-heptane to flocculate the asphaltenes and the amount in ml of xylene to disperse the flocs. The experimental design was Taguchi factorial with a response surface for one response variable (AII) and two experimental factors (the applied dose and heating temperature). For light crude oil, the optimum conditions were 8 μL and T = 127 °C with an 85.3 % efficiency and for medium crude oil, 2 μL and T = 25 °C with a 94.3 % efficiency. The efficiency of J. curcas oil and the influence of the type of crude oil on the results obtained were demonstrated.

Kinetics of Catalytic Decarboxylation of Naphthenic Acids over HZSM-5 Zeolite Catalyst

Naphthenic acids are naturally occurring carboxylic acids in crude oil with cyclic or aromatic rings in their structure. These carboxylic acids are responsible for the acidity of crude oil, leading to corrosion problems in refinery equipment and the deactivation of catalysts while creating a continuous need for maintenance. Therefore, removing naphthenic acids has become an important requirement in refining acidic crude oil. In this paper, experiments are conducted to investigate the use of HZSM-5 zeolite catalyst to reduce the total acid number (TAN) of a typical acidic crude oil obtained from Al-Fula blocks in Western Sudan. TAN is an important metric signifying the acidity of crude oil. A full factorial design of the experiment (DOE) framework enabled a better understanding of the efficacy of the catalyst at three parametric levels (reaction temperature: 250-270-300 °C, reaction time: 2-3-4 h, and oil:catalyst weight ratio: 20-22-25 g/g). The results demonstrate that the HZSM-5 zeolite catalyst provides up to 99% removal of naphthenic acids via the decarboxylation route. Additionally, the removal efficiency increases with increasing temperature and residence time. The acidity of the crude oil was shown to decrease after treatment with the catalyst for four hrs.; from 6.5 mg KOH/g crude to 1.24; 0.39 and 0.17 mg KOH/g at 250; 270 and 300 °C, respectively. A sharp decrease of TAN was observed at the oil catalyst mass ratio of 20 g/g at 250 °C, and almost complete conversion of acids was achieved after 4 hrs. Another experiment at 270 °C showed a converse relationship between the oil:catalyst ratio and acid removal; suggesting the activation of side reactions at higher temperature conditions catalyzed by excess acid. Finally; a Langmuir–Hinshelwood (LH) kinetic model has been developed to enable rapid prediction of the performance of the HZSM-5 zeolite catalyst for decarboxylation reaction. The model has also been validated and tested in ASPEN® software for future simulation and scalability studies.

Increasing Reservoir Recovery Efficiency through Laboratory-Proven Hybrid Smart Water-Assisted Foam (SWAF) Flooding in Carbonate Reservoirs

This contribution introduces a new hybrid enhanced oil recovery (EOR) method which combines smart water-assisted foam (SWAF) flooding, known as the SWAF process. The concept of applying SWAF flooding in carbonate reservoirs is a novel approach previously unexplored in the literature. The synergy effect of the SWAF technique has the potential to mitigate a number of limitations related to individual (i.e., conventional water injection and foam flooding) methods encountered in carbonates. In general, carbonate rocks are characterized by a mixed-wet to oil-wet wettability state, which contributes to poor oil recovery. Hence, the smart water solution has been designed to produce a dual-improvement effect of altering carbonate rock wettability towards more water-wet, which preconditions the reservoir and augments the stability of the foam lamellae, which has for some conditions more favorable relative permeability behavior. Then the smart water solution is combined with surfactant (surfactant aqueous solution or SAS) and gas injection produces a synergy effect, which leads to more wettability alteration, and interfacial tension (IFT) reduction, and thus improves the oil recovery. Accordingly, to determine the optimal conditions of smart water solution with an optimal SAS, we conducted a series of experimental laboratory studies. The experimental design is divided into three main steps. At first, the screening process is required so that the candidates can be narrowed down for our designed smart water using the contact angle tests that employ calcite plate (i.e., Indiana limestone or ILS) as the first filter. Following this, the optimum smart water solutions candidates are blended with different types of cationic and anionic surfactants to create optimum SAS formulations. Subsequently, a second screening process is performed with the aim to narrow down the SAS candidates with varying types of gases (i.e., carbon dioxide, CO2 and nitrogen, N2) via the aqueous stability test (AST), foamability test (FT), and foam stability test (FST). We employed the state-of-the-art R5 parameter tests for rapid and accurate results in place of the conventional foam half-life method. The most effective combination of SAS and gas candidates are endorsed for the core-flooding experiments. In this work, two types of crude oils (Type A and B) with different total acid and base numbers (TAN and TBN). Results showed that the greatest wettability changes occurred for SW (MgCl2) solution at 3500 (ppm) for both crude oil types. This demonstrates the efficacy of our designed SW in the wettability alteration of carbonates, which is also supported by the zeta-potential measurements. The concentrations of both SW (MgCl2) and CTAB-based surfactants considerably affect the stability of the SAS (i.e., up to 90% foam stability). However when in the presence of crude oil, for the same SAS solution, the foam stability is reduced from 90% to 80%, which indicates the negative effect of crude oil on foam stability. Moreover, the core floods results showed that the MgCl2-foam injection mixture (MgCl2 + CTAB + AOS + N2) provided the highest residual oil recovery factor of SWAF process of 92% cumulative recovery of original oil in core (OIIC). This showcases the effectiveness of our proposed SWAF technique in oil recovery from carbonate reservoirs. Additionally, changing the large slug of 5 PVs to a small slug of 2 PVs of smart water solution was more effective in producing higher OIIC recovery and in reducing the fluid circulation costs (i.e., thereby, lowering CO2 footprint), making the SWAF process environmentally benign. Thus, it is expected that under optimum conditions (SW solution and SAS), the novel SWAF process can be a potentially successful hybrid EOR method for carbonate reservoirs, having both economic and environmental benefits.

Corrosion Control Mechanisms and the Effect of pH on Corrosion in the Crude Oil Refining Process

The consequences of corrosion in the crude oil refining process cannot be ignored due to the damage caused by the corrosion of oil equipment, and the serious losses that result from that. Therefore, in this research, methods of controlling the occurrence of corrosion in the crude oil refining unit in the Najaf refinery for four types of crude oil - API (28, 28.2, 29.2, and 30.2) were studied. Chemicals were added in different quantities and types before and during the crude oil refining process to the atmospheric distillation unit, where it was found that these chemicals have the ability to make a media within the limits of pH from 5.5 to 6.5, where the corrosion became little or no. Also, an anti-corrosion chemical was added, which reduced the incidence of corrosion in the overhead systems of crude oil refining equipment. In addition to treating the crude oil using desalter before refining it, where the mud and dirt and a large proportion of the salts in the emulsified water were removed from crude oil. The best results obtained were pH (6, 6, 5.7, and 5.5) and the percentage of iron ions Fe+2 ( 0.8, 1, 1.5, and 2.1) for four types of refined crude oil at using pump dosages for inhibitor (2.5, 2, 3.5 and 3.5), caustic soda (4, 6, 8, and 8) and neutralizer (2, 2.5, 3, and 3). This practical study showed the importance of adding chemicals in different quantities, as well as electrical and thermal treatment in controlling and preventing corrosion of oil equipment in the crude oil refining unit.

Experimental investigation of different characteristics of crude oil on the interfacial activity of anionic, cationic and nonionic surfactants mixtures

The current study investigates the synergistic/antagonistic effect of cationic (octyl pyridinium chloride [C8Py][Cl]), anionic (sodium lauryl sulfate (SLS)), and nonionic (octyl phenol ethoxylate (Triton-X100)) surfactants on the interfacial tension (IFT) reduction. The performance of the mixture of surfactants in the presence of different electrolytes on the IFT values of five crude oil samples are evaluated. To better understand the molecular interaction between surfactant solutions and oil samples, the important parameters such as °API, total acid and base numbers, asphaltene and resin weight percent, resin to asphaltene ratio, weight percent of oxygen, nitrogen and sulfur elements, and aromaticity of asphaltene and resin fractions are thoroughly examined. It is found that the synergistic effect between crude oil and surfactant solutions depends on the crude oil and surfactant types and salinity of brine. In this way, the mixture of anionic-cationic had the best results with an IFT value lower 0.1 mN/m. Although no specific trend was observed for the effect of oil type on the IFT of mixtures, the results showed that the ionic strength and surfactant type had a more dominant effect than the oil type. The mechanisms of IFT reduction for each binary mixture are also thoroughly discussed.

Sustainable strategies for combating hydrocarbon pollution: Special emphasis on mobil oil bioremediation

The global rise in industrialization and vehicularization has led to the increasing trend in the use of different crude oil types. Among these mobil oil has major application in automobiles and different machines. The combustion of mobil oil renders a non-usable form that ultimately enters the environment thereby causing problems to environmental health. The aliphatic and aromatic hydrocarbon fraction of mobil oil has serious human and environmental health hazards. These components upon interaction with soil affect its fertility and microbial diversity. The recent advancement in the omics approach viz. metagenomics, metatranscriptomics and metaproteomics has led to increased efficiency for the use of microbial based remediation strategy. Additionally, the use of biosurfactants further aids in increasing the bioavailability and thus biodegradation of crude oil constituents. The combination of more than one approach could serve as an effective tool for efficient reduction of oil contamination from diverse ecosystems. To the best of our knowledge only a few publications on mobil oil have been published in the last decade. This systematic review could be extremely useful in designing a micro-bioremediation strategy for aquatic and terrestrial ecosystems contaminated with mobil oil or petroleum hydrocarbons that is both efficient and feasible. The state-of-art information and future research directions have been discussed to address the issue efficiently.

Prices

Assessed or estimated prices and values for the major types of crude oils traded on spot markets. Updated on a monthly basis.Official sales prices (except as otherwise noted) and are generally market‐related, subject in some cases to retroactive adjustment. Updated on a monthly basis.

Technology Focus: Heavy Oil (April 2022)

Heavy oils are characterized by high density, high viscosity, and high-heavy-fraction components. Because of high viscosity and lower API gravity than conventional crude oil, primary recovery of some of these crude oil types requires thermal stimulation of the reservoirs. Most of the technologies that deal with heavy oil need to address the mobility ratio or viscous forces before any flooding. In general, poor recovery is caused by physical reasons or geological reasons. Physical reasons can be categorized as capillary forces (existence of the interfacial tension between oil and water, wettability) or viscous forces (high mobility ratio between water and oil). Geological reasons are heterogeneities in reservoir rock and exist in all petroleum oil systems. In heavy oil reservoirs, enhanced oil recovery (EOR) intends to reduce the capillary forces and interfacial tension to improve microscopic displacement efficiency or improve the sweep efficiency (macroscopic) by reducing the mobility ratio between injected fluid and displaced fluid. Improving the mobility ratio is achieved by increasing the viscosity of water using polymers or by reducing the oil viscosity using heat. In general, all technologies need to address the capillary and viscous forces to improve oil recovery. Paper SPE 207361 discusses improving of the efficiency of the flood by near-wellbore conformance and improving the vertical sweep efficiency. The use of fiber-optic sensors, as addressed in paper SPE 199023, is intended to gather better data and avoid misinterpretation during falloff tests and injectivity tests. Traditionally, for heavy oil EOR simulation, because of the addition of chemical species or heat to the flow equations as well as the need for a finer grid resolution, the use of the full-field model in most cases was limited and the use of sector models and local grid refinement to obtain a reasonable accuracy has been applied in the industry. Sector modeling conditions must be satisfied to establish the reliability and the trade-off between accuracy (sector models) and computational expediency (full-field model). Recent development of hardware and software [graphics-processing-unit (GPU) -based simulators] has provided the industry with the tools to achieve a full-field model simulation in most fields by taking advantage of GPU solvers and using a fine-grid model to predict full-field performance. Recommended additional reading at OnePetro: www.onepetro.org. SPE 200279 - Field Application of the Autonomous Inflow Control Device for Optimized Heavy Oil Production in South Sultanate of Oman by Ali Al-Jumah, Petroleum Development Oman, et al. SPE 203012 - More Oil and Less Water: Autonomous Inflow Control Devices in New and Old Producers in Heavy Oil Fields From South of Oman by Ameera Al Harrasi, Petroleum Development Oman, et al. SPE 207684 - Game Changer in Dealing With Hard Scale Using a Slickline Torque Action Debris Breaker by Mahmoud Mohamed Koriesh, Dragon Oil, et al.

Research on nonlinear rheological properties of waxy crude oil based on large amplitude oscillatory shearing

The rheological properties of waxy crude oil are important for its economical and safe pipeline transportation. In actual pipeline transportation, waxy crude oil often exhibits nonlinear rheological characteristics, among which viscoelastic-thixotropic characteristics are the main ones, while there are currently few related studies. This article carried out a study of large amplitude oscillatory shearing (LAOS) for typical Daqing waxy crude oil, and conducted analysis of the nonlinear rheological characteristics of the low temperature waxy crude oil based on the periodic strain loading mode. Using the Fourier transform rheology, Lissajous curve, and stress decomposition method, the effects of strain amplitude and frequency on the nonlinear rheological characteristics under LAOS conditions are analyzed. Results show that when the Fourier transform method analyzes the non-linear rheological characteristics area, the relative intensities of frequency triple and frequency quintuple increase with the increase of strain amplitude and frequency, and it cannot accurately reflect the non-linear rheological properties of waxy crude oil under high-frequency conditions. The Lissajous curve method is more suitable for the study of the nonlinear rheological characteristics of waxy crude oil under low frequency conditions and establishing a prediction formula of dissipated energy density. In addition, the nonlinear viscoelastic parameters obtained by the stress decomposition method can accurately characterize the nonlinear viscoelasticity of waxy crude oil. This research deeply explores the nonlinear rheological properties of waxy crude oil, which can provide theoretical guidance for practice.

A New MINLP Continuous Time Formulation for Scheduling Optimization of Oil Refinery with Unreliable CDUs

Short-term scheduling of oil refinery operations is a complicated optimization problem that requires a high level of detail and needs efficient approaches and software tools. Oil refineries are naturally categorized as continuous process industries due to their production processes, which have essentially different characteristics and constraints from discrete manufacturing processes. It is a significant problem to design effective approaches for oil refinery scheduling optimization. Therefore, this paper aims to provide solutions to the above very challenging problem by proposing a novel methodology. The problem is how to optimize crude oil unloading to charging tanks and charging schedules for different types of crude oils to distillation units (CDUs). Several realistic operational features are considered, such as different arrival times for crude oils, continuous operation of CDUs, no rework of crude oils, and the ability to perform preventative maintenance on CDUs. To solve this problem effectively, a new mixed-integer nonlinear programming (MINLP) model is developed. Industrial case studies are used to demonstrate the effectiveness of the proposed formulation. The computational results show that the case studies are effectively solved with the proposed solution approach.

Crude oil emulsion breaking: An investigation about gravitational and rheological stability under demulsifiers action

Emulsions are common in the oil industry, being present in the extraction and production stages. Its formation occurs with the contact of brine and crude oil under intense flow. The presence of emulsified water (dispersed droplet size, φ ≤ 50 μm) in crude oil can negatively impact its exploration, transportation, and refining, making transportation more expensive, requiring more energy for heating, and causing equipment corrosion on all processes. In addition, crude oil has salts and sediments that encrust and corrode equipment of the primary oil treatment unit and distillation towers, also causing catalyst poisoning in the cracking step. Therefore, such components need to be removed for subsequent refining processes. To prevent these problems, the dehydration/desalting of crude oils is a strategy adopted to reach adequate values of water, salts, and sediments required in the refineries for the next steps after primary treatment. However, the emulsion breaking is influenced by several factors that affect the stability of crude oil (W/O emulsion), such as viscosity, contents of water, salts, sediments, and natural surfactants, among others. Given this perspective, this work investigated the stability of two different types of crude oils with demulsifier under the action of gravity (bottle test) and shear stress (rheology). The comparisons of gravitational and rheological techniques concluded that the shear stress sweep analyses are useful to evaluate the demulsifier performance in the emulsion breaking, being a reliable and fast methodology. Such studies allowed the identification of adequate parameters: temperature (80 °C) and, demulsifier type and quantity (500 ppm) for efficient crude oil phase separation, without using washing water. The physicochemical and rheological characterizations clarified the crude oil's colloidal stability behavior to understand the impurities' influence on the oils' properties (crude and desalted).