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heavy-oil
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In-depth characterization of light, medium and heavy oil asphaltenes as well as asphaltenes subfractions
, Article Fuel ; Volume 324 , 2022 ; 00162361 (ISSN) ; Husein, M. M ; Ghotbi, C ; Dabir, B ; Taghikhani, V ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Asphaltenes, and their related issues, have been the focus of many literature investigations. However, in-depth analysis of asphaltenes structure and its relation to asphaltenes stability has been considered by fewer studies. In this research, extensive analysis of the structure of asphaltenes extracted from light, medium, and heavy oils is provided, together with analysis of three subfractions of the medium oil asphaltene having the least, intermediate, and highest solubilities. To this end, elemental analysis, EDX, mass spectroscopy, FTIR, NMR, XRD, and SEM results were collected. Higher hydrogen content and hydrogen/carbon atomic ratio, lower aromatic nature and olefinic entities were...
Biological upgrading of heavy oil cuts using native microbial consortia as an environmental-friendly technology in petroleum refineries
, Article Advances in Environmental Technology ; Volume 8, Issue 3 , 2022 , Pages 215-228 ; 24766674 (ISSN) ; Ziaei Rad, Z ; Shayegan, J ; Pazouki, M ; Hossinia, A ; Sharif University of Technology
Iranian Research Organization for Science and Technology
2022
Abstract
Refineries are amongst the most energy-intensive and polluting industries in the world. Biotechnology may serve as an alternative low-cost and environmental-friendly tool to the current costly, toxic and hazardous refining processes. In this study, the compositional redistribution of a heavy hydrocarbon cut is investigated under biological conversion using native microbial consortia. The native consortia were obtained by batch enrichment method applied on oil-polluted soil samples from oil refineries of Iran. The bioconversion experiments were conducted with 20% and 40% (v/v) of the heavy cut as the sole carbon source and 10% (v/v) of the consortia broth in 250 ml flasks containing a mineral...
Numerical simulation of cold and hot water injection into naturally fractured porous media using the extended–FEM and an equivalent continuum model
, Article International Journal for Numerical and Analytical Methods in Geomechanics ; Volume 46, Issue 3 , 2022 , Pages 617-655 ; 03639061 (ISSN) ; Pirmoradi, P ; Khoei, A. R ; Sharif University of Technology
John Wiley and Sons Ltd
2022
Abstract
In this paper, a computational technique is presented for the isothermal and non-isothermal water injection into naturally fractured oil reservoirs. A remarkable number of naturally fractured reservoirs contain relatively heavy oils that could not be extracted economically; hence, the thermal recovery methods are extensively used for such reservoirs. In this study, the effectiveness of hot water injection over cold (isothermal) water injection in oil production is quantified. The influence of long and short fractures and their alignments on oil recovery are discussed. To this end, a 2D model for two-phase fluid flow and heat transfer is presented. The medium is assumed to be partially...
Numerical simulation of cold and hot water injection into naturally fractured porous media using the extended–FEM and an equivalent continuum model
, Article International Journal for Numerical and Analytical Methods in Geomechanics ; 2021 ; 03639061 (ISSN) ; Pirmoradi, P ; Khoei, A. R ; Sharif University of Technology
John Wiley and Sons Ltd
2021
Abstract
In this paper, a computational technique is presented for the isothermal and non-isothermal water injection into naturally fractured oil reservoirs. A remarkable number of naturally fractured reservoirs contain relatively heavy oils that could not be extracted economically; hence, the thermal recovery methods are extensively used for such reservoirs. In this study, the effectiveness of hot water injection over cold (isothermal) water injection in oil production is quantified. The influence of long and short fractures and their alignments on oil recovery are discussed. To this end, a 2D model for two-phase fluid flow and heat transfer is presented. The medium is assumed to be partially...
A mechanistic understanding of the water-in-heavy oil emulsion viscosity variation: effect of asphaltene and wax migration
, Article Colloids and Surfaces A: Physicochemical and Engineering Aspects ; Volume 608 , 2021 ; 09277757 (ISSN) ; Hemmati, M ; Safari, M ; Rahimi, A ; Rahmani, O ; Aminpour, S. M ; Beiranvand Pour, A ; Sharif University of Technology
Elsevier B.V
2021
Abstract
The role of emulsions as a prevalent phenomenon is broadly investigated in the petroleum industry since forming the emulsion has many severe harmful implications. Heavy components of crude oil such as wax and asphaltene make the water-in-oil (w/o) emulsion more stable, while the role of these components on the emulsion viscosity has not been fully understood. In this regard, to find a proper demulsifier to break these emulsions, it is necessary to know the mechanisms of emulsion formation by heavy oil components. In this study, the effects of waxy-oil and asphaltenic-oil on w/o emulsion were investigated by measuring volume and viscosity of the formed emulsion after an elapsed time, followed...
Numerical study on NOx reduction in a large-scale heavy fuel oil-fired boiler using suitable burner adjustments
, Article Energy ; Volume 199 , 2020 ; Fatin, A ; Bordbar, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
A numerical framework was carefully developed to simulate the combustion of heavy-fuel-oil (HFO) in a large-scale boiler. The present numerical solutions were compared with the measured data of a laboratory benchmark test and on-site operational data of the chosen HFO-fired boiler. Next, the developed framework was used to perform sensitivity analyses aiming to reduce the NO emission from the HFO-fired boiler without any adverse effect on its combustion performance. Practically, this study focused on re-adjustments of 24 working burners, which could control combustion in the HFO-fired boiler. The early outcome showed that the boiler NO emission and its combustion performance could be...
Fractal analysis of asphaltene aggregation phenomena in live oils at elevated pressure and temperature
, Article Particulate Science and Technology ; Volume 38, Issue 4 , 2020 , Pages 454-463 ; Rashidi, F ; Mousavi Dehghani, S. A ; Ghazanfari, M. H ; Sharif University of Technology
Taylor and Francis Inc
2020
Abstract
In this work, high-pressure microscopy technique was used to measure the size and fractal dimension of asphaltene aggregates formed in different live oil samples at elevated pressures and temperatures. It was found that the asphaltene aggregates in live oil samples are irregular fractal-like structures with pressure−temperature-dependent fractal dimensions. By monitoring the variation of the fractal dimension and size of the asphaltene aggregates with pressure and temperature, the mechanisms responsible for asphaltene aggregation process at elevated pressures and temperatures can be well predicted. The range of fractal dimension of asphaltene aggregates in live oils is similar to that...
Heavy oil thermal conversion and refinement to the green petroleum: A petrochemical refinement plant using the sustainable formic acid for the process
, Article Biointerface Research in Applied Chemistry ; Volume 10, Issue 5 , 2020 , Pages 6088-6100 ; Talebi, S ; Fabi, M ; Khajehpour, H ; Sharif University of Technology
AMG Transcend Association
2020
Abstract
In this study, heat oil conversion experiments using steam and formic acid as a hydrogen carrier be carried out in a batch reactor at T = 380 degrees of Celsius and P = 165 bar. Material balance and product distribution were calculated after the process. Properties of crude oil before and after thermal conversion, including viscosity, API gravity, SARA measurement, and elemental analysis, were analyzed. It has been presented that the use of formic acid as a hydrogen carrier solvent reduces the formation of coke and gaseous products and enhances the performance of liquid products. Also, the viscosity of the refined oil decreased by 23.2% due to the addition of formic acid compared to the...
Optimal distribution function determination for plus fraction splitting
, Article Canadian Journal of Chemical Engineering ; Volume 97, Issue 10 , 2019 , Pages 2752-2764 ; 00084034 (ISSN) ; Khoozan, D ; Jamshidi, S ; Sharif University of Technology
Wiley-Liss Inc
2019
Abstract
Reservoir fluid modelling is one of the most important steps in reservoir simulation and modelling of flow lines as well as surface facilities. One of the most uncertain parameters of the reservoir fluids is the plus fraction. An accurate and consistent splitting scheme can reduce this uncertainty and as a result, enhance the modelling of reservoir fluids. The existing schemes for splitting plus fractions are all based on assuming a specific mole fraction-molecular weight distribution with predefined constant values that may yield inaccurate and inconsistent results. In this study, an optimization-based algorithm was developed to determine the aforementioned controlling parameters of the...
The effect of brine salinity on water-in-oil emulsion stability through droplet size distribution analysis: a case study
, Article Journal of Dispersion Science and Technology ; Volume 39, Issue 5 , 2018 , Pages 721-733 ; 01932691 (ISSN) ; Ayatollahi, S ; Sharif University of Technology
Taylor and Francis Inc
2018
Abstract
Water-in-oil emulsion usually forms during waterflooding in some heavy oil reservoirs. The composition and salinity of the injected water critically affect the w/o emulsion droplet size distribution, which control the emulsion stability and emulsion flow in porous media. The aim of the present work is to assess the effect of different sea water salinities on w/o emulsion stability through microscopic imaging. Therefore, w/o emulsions were prepared with different sea water samples, which were synthesized to resemble Persian Gulf, Mediterranean, Red Sea, and North Sea water samples. The results showed that log-normal distribution function predicts very well the experimental data to track the...
A new approach to characterize the performance of heavy oil recovery due to various gas injection
, Article International Journal of Multiphase Flow ; Volume 99 , 2018 , Pages 273-283 ; 03019322 (ISSN) ; Pourafshary, P ; Fathollahi, A ; Yassin, M. R ; Hassani, K ; Khosravi, M ; Mohammadifard, M ; Dangkooban, A ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The performance of CO2 injection into a semi-heavy oil reservoir was investigated at reservoir conditions, using highly permeable sandstone in a complete series of PVT tests and coreflooding experiments. Analysis of involved parameters such as: injection rate, injectant type and reservoir pressure were also considered. Oil viscosity reduction and oil swelling are the most influential mechanisms of enhanced oil recovery in this process. The results demonstrated that CO2 injection would decrease the interfacial tension for the high permeable medium in the absence of capillarity, but this reduction may not improve the recovery drastically. One of the main important aspects of this work is the...
Effect of ultrasonic irradiation treatment on rheological behaviour of extra heavy crude oil: A solution method for transportation improvement
, Article Canadian Journal of Chemical Engineering ; Volume 95, Issue 1 , 2017 , Pages 83-91 ; 00084034 (ISSN) ; Ramazani S. A, A ; Alijani Alijanvand, H ; Ghazanfari, M. H ; Ghanavati, M ; Sharif University of Technology
Wiley-Liss Inc
2017
Abstract
The highly viscous property of heavy oil often causes problems in its transportation in pipelines. Mixing heavy oil with light oil as well as ultrasound treatment are viable solutions to this problem. In this study, extra heavy crude oil samples were first diluted with 0, 0.05, 0.1, and 0.15 mL/mL (0, 5, 10, and 15 vol%) of a light crude oil; then the mixture was irradiated by ultrasonic waves for 0, 5, 10, 15, and 20 min; finally the viscous shear functions of all mixtures was measured at different values of shear rate at different temperature levels. The results revealed that the minimum viscosity of the diluted extra heavy crude oil samples was obtained at 10 min of ultrasonic...
A new approach to characterize the performance of heavy oil recovery due to various gas injection
, Article International Journal of Multiphase Flow ; 2017 ; 03019322 (ISSN) ; Pourafshary, P ; Fathollahi, A ; Yassin, M. R ; Hassani, K ; Khosravi, M ; Mohammadifard, M ; Dangkooban, A ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
The performance of CO2 injection into a semi-heavy oil reservoir was investigated at reservoir conditions, using highly permeable sandstone in a complete series of PVT tests and coreflooding experiments. Analysis of involved parameters such as: injection rate, injectant type and reservoir pressure were also considered. Oil viscosity reduction and oil swelling are the most influential mechanisms of enhanced oil recovery in this process. The results demonstrated that CO2 injection would decrease the interfacial tension for the high permeable medium in the absence of capillarity, but this reduction may not improve the recovery drastically. One of the main important aspects of this work is the...
Thermogravimetric analysis and kinetic study of heavy oil pyrolysis
, Article Petroleum Science and Technology ; Volume 34, Issue 10 , 2016 , Pages 911-914 ; 10916466 (ISSN) ; Hami, M. R ; Sharif University of Technology
Taylor and Francis Inc
2016
Abstract
ABSTRACT: Pyrolysis, so-called devolatilization, is one of the first steps of all thermochemical processes occurring in an inert atmosphere. The authors discuss the main kinetic features of heavy oil pyrolysis, on the basis of the data derived m from a TGA analysis and by using a kinetic model. The samples were heated over a range of temperature from 400 K to 430°C at various heating rates between 10 and 80°C/min. Experimental results showed that the effect of time is considerable in the case of tar conversion, compared to char and gases
Fractal analysis of asphaltene aggregation phenomena in live oils at elevated pressure and temperature
, Article Particulate Science and Technology ; 2016 , Pages 1-9 ; 02726351 (ISSN) ; Rashidi, F ; Mousavi Dehghani, S. A ; Ghazanfari, M. H ; Sharif University of Technology
Taylor and Francis Inc
2016
Abstract
In this work, high-pressure microscopy technique was used to measure the size and fractal dimension of asphaltene aggregates formed in different live oil samples at elevated pressures and temperatures. It was found that the asphaltene aggregates in live oil samples are irregular fractal-like structures with pressure−temperature-dependent fractal dimensions. By monitoring the variation of the fractal dimension and size of the asphaltene aggregates with pressure and temperature, the mechanisms responsible for asphaltene aggregation process at elevated pressures and temperatures can be well predicted. The range of fractal dimension of asphaltene aggregates in live oils is similar to that...
Heavy oil recovery using ASP flooding: A pore-level experimental study in fractured five-spot micromodels
, Article Canadian Journal of Chemical Engineering ; Volume 94, Issue 4 , 2016 , Pages 779-791 ; 00084034 (ISSN) ; Mohammadzadeh, O ; Kord, S ; Chatzis, I ; Sharif University of Technology
Wiley-Liss Inc
2016
Abstract
Although alkaline-surfactant-polymer (ASP) flooding has proven efficient for heavy oil recovery, the displacement mechanisms and efficiency of this process should be discussed further in fractured porous media. In this study, several ASP flooding tests were conducted in fractured glass-etched micromodels with a typical waterflood geometrical configuration, i.e. five-spot injection-production pattern. The ASP flooding tests were conducted at constant injection flow rates but different fracture geometrical characteristics. The ASP solutions consisted of five polymers, two surfactants, and three alkaline types. It was found that using synthetic polymers, especially hydrolyzed polyacrylamide...
Phase behavior and interfacial tension evaluation of a newly designed surfactant on heavy oil displacement efficiency; effects of salinity, wettability, and capillary pressure
, Article Fluid Phase Equilibria ; Volume 396 , 2015 , Pages 20-27 ; 03783812 (ISSN) ; Masihi, M ; Ayatollahi, S ; Sharif University of Technology
Elsevier
2015
Abstract
This work aims to discuss the results of wide ranges of laboratory investigations to evaluate the performance of a newly-formulated surfactant for heavy oil reservoirs in order to improve the microscopic sweep efficiency after water flooding processes. In the first part, the specific behavior of the formulated surfactant including its salinity tolerance, interfacial tension, and optimum performance window was determined. Then, the application of surfactant solutions in real sandstone reservoir rocks was assessed for both oil-wet and water-wet cases. Besides, the effect of changing the capillary and viscous forces and interfacial tension on the residual phase saturations were characterized....
Experimental investigation of heavy oil recovery by continuous/WAG injection of CO2 saturated with silica nanoparticles
, Article International Journal of Oil, Gas and Coal Technology ; Volume 9, Issue 2 , 2015 , Pages 169-179 ; 17533317 (ISSN) ; Khezrnejad, A ; Shahrokhi, O ; Ghazanfari, M. H ; Vossoughi, M ; Sharif University of Technology
Inderscience Enterprises Ltd
2015
Abstract
In this work, application of CO2 saturated with silica nanoparticles in continuous/water alternating gas (WAG) injection for heavy oil recovery was investigated which has been rarely attended in the available literature. Core displacement tests were conducted to monitor heavy oil recovery in both continuous and WAG injection schemes. It has been observed that for continuous nano-saturated CO2 injection, the oil recovery is higher than pure CO2 injection. This observation might be explained by alteration of rock wettability to a more water-wet condition. In WAG injection scheme, water breakthrough happened later in nano-saturated CO2 than pure CO2 injection. This delayed water breakthrough...
Characterization of viscous fingering during displacements of low tension natural surfactant in fractured multi-layered heavy oil systems
, Article Chemical Engineering Research and Design ; Volume 96 , 2015 , Pages 23-34 ; 02638762 (ISSN) ; Shokrollahi, A ; Ghazanfari, M. H ; Rashtchian, D ; Sharif University of Technology
Institution of Chemical Engineers
2015
Abstract
Characterization of viscous fingering in low tension displacements especially for heavy oil surfactant pair in heterogeneous systems is neither straight forward nor well understood. In this work layered porous models containing fractures with different geometrical properties were used and the finger behavior during displacement of LTNS, as a new EOR agent, in heavy oil was quantified. Dynamic propagation of the fingers independent to the type of heterogeneity is well correlated with the dimensionless displacement time in a linearly form. And also, the rate of finger growth is nearly independent to the type of medium heterogeneity. When injection is scheduled through high permeable region in...
Macroscopic and microscopic investigation of alkaline-surfactant-polymer flooding in heavy oil recovery using five-spot micromodels: The effect of shale geometry and connatewater saturation
, Article Journal of Porous Media ; Volume 18, Issue 8 , 2015 , Pages 745-762 ; 1091028X (ISSN) ; Ghazanfari, M. H ; Masihi, M ; Rashtchian, D ; Sharif University of Technology
Begell House Inc
2015
Abstract
Plenty of oil reservoirs contain discontinuous shale layers that act as flow barriers. Therefore, understanding their influences on reservoir performance, especially during enhanced oil recovery (EOR) processes, is of great importance. For this purpose, several experiments of water and alkaline-surfactant-polymer (ASP) flooding have been performed on a number of one-quarter five-spot micromodels that contain various configurations of shale layers to simulate shaly porous media. Several features, such as various shale geometrical characteristics and the presence of connate water saturation, were investigated at both macro- and micro-scales. The presence of shales resulted in earlier...