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temperature-and-pressures
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A new method in well test interpretation using temperature transient analysis for gas wells
, Article International Petroleum Technology Conference 2007, IPTC 2007, Dubai, 4 December 2007 through 6 December 2007 ; Volume 2 , 2007 , Pages 1151-1160 ; 9781615673360 (ISBN) ; Siavoshi, J ; Sharif University of Technology
Society of Petroleum Engineers
2007
Abstract
Interpretation of temperature logs has been done successfully in wells to identify water or gas entries location, detect casing leaks, and evaluate cement placement. This paper shows how knowledge of the Joule-Thomson cooling effect and frictional heating effect can be applied for well test interpretation. Many analysts rely on pressure derivative curve to diagnose wellbore storage period and radial flow regime on pressure transient data. However, there are field examples that flow regimes can't be accurately determined. During transient tests, both pressure and temperature are changed depending on downhole flow rate. In gas producing wells, Joule-Thomson cooling and frictional heating...
Complexity of density dependencies of thermal and internal pressure compared to that of total pressure
, Article Industrial and Engineering Chemistry Research ; Volume 52, Issue 23 , May , 2013 , Pages 8034-8045 ; 08885885 (ISSN) ; Parsafar, G ; Sharif University of Technology
2013
Abstract
A simple equation of state (EoS) has recently been introduced (J. Phys. Chem. B2009, 113, 11977-11987) as (Z - 1)v2 = e + f/ρ + gρ2, where Z ≡ pv/RT is the compressibility factor, v = 1/ρ is molar volume, and e, f, and g are temperature dependent parameters. This EoS has been found to be accurate for all types of nano and bulk solids and bulk fluids, in the entire temperature and pressure ranges for which experimental data are reported, except for the isotherms within 1 ≤ T r = T/Tc ≤ 1.1 for the spherical and near spherical species and for a wider temperature range for the cylindrical molecules. The aim of this work is to investigate the validity of a three-term expression similar to the...
Reversibility of Asphaltene Aggregation in Live Oils: Qualitative and Quantitative Evaluation
, Article Journal of Chemical and Engineering Data ; Volume 60, Issue 9 , August , 2015 , Pages 2646-2654 ; 00219568 (ISSN) ; Rashidi, F ; Mousavi Dehghani, S. A ; Ghazanfari, M. H ; Sharif University of Technology
American Chemical Society
2015
Abstract
Despite the numerous experimental studies concerning asphaltene, the extent of reversibility of asphaltene aggregation at reservoir conditions remains still an elusive and controversial issue in the available literature. In this work, a series of depressurization and repressurization experiments were performed on three different live oils for qualitative and quantitative evaluation of the reversibility of asphaltene aggregation under typical pressure and temperature conditions of oil fields. The obtained results reveal that the kinetics and the extent of reversibility of asphaltene aggregation at elevated pressure and temperature are majorly controlled by the characteristics of the reservoir...
Investigation of effects of salinity, temperature, pressure, and crude oil type on the dynamic interfacial tensions
, Article Chemical Engineering Research and Design ; Volume 115 , 2016 , Pages 53-65 ; 02638762 (ISSN) ; Riazi, M ; Ayatollahi, S ; Sharif University of Technology
Institution of Chemical Engineers
2016
Abstract
The main objectives of this study are to determine the influence of crude oil type, salinity, temperature and pressure on the dynamic interfacial tension (DIFT) of crude oil based on the experiments and modeling approaches. DIFT is also modeled using dynamic adsorption models, mono-exponential decay model as well as empirical equations. The results showed that when temperature increases, unlike deionized water which inversion phase temperature was observed, the equilibrium IFT of crude oils/sea water increases due to reduction of surface excess concentration of natural surfactants at the fluid/fluid interface as a dominant mechanism
Constants of explosive limits
, Article Chemical Engineering Science ; Volume 173 , 2017 , Pages 384-389 ; 00092509 (ISSN) ; Jafari, M ; Farrokhpour, H ; Keshavarz, M. H ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
This work defines density factor as the ratio of before ignition density to after ignition density of the ignition mixture. This work provides an estimation method for explosive limits of various fuels under room temperature and pressure by showing that for a large universe of fuels, constant adiabatic flame temperature and density factor are appropriate approximations at the lower explosive limit while only a constant density factor might be an appropriate approximation at the upper explosive limit. Thus the assumption of a constant adiabatic flame temperature can be used in calculating lower explosive limit while the assumption of a constant density factor can be used in approximating...
Toward mechanistic understanding of heavy crude oil/brine interfacial tension: The roles of salinity, temperature and pressure
, Article Fluid Phase Equilibria ; Vol. 375, issue , August , 2014 , p. 191-200 ; ISSN: 03783812 ; Hemmati-Sarapardeh, A ; Ghazanfari, M. H ; Masihi, M ; Ayatollahi, S ; Sharif University of Technology
Abstract
Injecting low salinity brines is regarded as an enhanced oil recovery (EOR) process through IFT reduction. However, the exact mechanism behind this process is an unsettled and complex issue that has not been well understood yet, especially for heavy crude oil system. Besides, limited information is available regarding the key heavy oil/brine interfacial tension (IFT). The present study aims to investigate the sensitivity of dead heavy crude oil/brine IFT to a wide range of properties/conditions and to reveal the underlying physicochemical mechanisms involved in enhanced oil recovery and IFT reduction by low salinity water injection into heavy oil reservoir. IFT was measured as a function of...
Experimental investigation of flooding hydrolyzed-sulfonated polymers for EOR process in a carbonate reservoir
, Article Petroleum Science and Technology ; Vol. 32, issue. 9 , Mar , 2014 , p. 1114-1122 ; ISSN: 10916466 ; Nourani, M ; Ramazani, A ; Masihi, M ; Sharif University of Technology
Abstract
The main purposes of this study were to scrutinize experimentally effects of polymer and rock types on the oil recovery using water and polymer flooding processes. Four dynamic flooding experiments were carried out at simulated reservoir condition of temperature and pressure. According to the obtained results, the ultimate oil recovery by water flooding in highly fractured reservoirs was less than reservoirs with the microfractures. The results of polymer flooding showed that in addition the polymer molecular weight, the sulfonation of polymers also affects the oil recovery
A novel field ionization gas sensor based on self-organized CuO nanowire arrays
, Article Sensors and Actuators, A: Physical ; Vol. 216 , 2014 , pp. 202-206 ; ISSN: 09244247 ; Ahmadvand, H ; Iraji Zad, A ; Sharif University of Technology
Abstract
In this study, we present fabrication and characterization of a gas ionization sensor based on high aspect ratio one-dimensional CuO nanowires as the field enhancing medium. Self-organized arrays of CuO nanowires have been synthesized based on a low-cost thermal oxidation method and integrated into a gas ionization sensor (GIS). The self-organized arrays of CuO nanowires have been employed to detect the identity of several gas species such as He, Ar and CO at ambient temperature and pressure. The sharp nanoscale size of CuO tips provide very high electric fields at moderate voltages (less than 100 V) and provoke the breakdown of different gases. The reduced breakdown current of the metal...
Toward mechanistic understanding of heavy crude oil/brine interfacial tension: The roles of salinity, temperature and pressure
, Article Fluid Phase Equilibria ; Vol. 375, issue , 2014 , Pages 191-200 ; ISSN: 03783812 ; Hemmati-Sarapardeh, A ; Ghazanfari, M. H ; Masihi, M ; Ayatollahi, S ; Sharif University of Technology
Abstract
Injecting low salinity brines is regarded as an enhanced oil recovery (EOR) process through IFT reduction. However, the exact mechanism behind this process is an unsettled and complex issue that has not been well understood yet, especially for heavy crude oil system. Besides, limited information is available regarding the key heavy oil/brine interfacial tension (IFT). The present study aims to investigate the sensitivity of dead heavy crude oil/brine IFT to a wide range of properties/conditions and to reveal the underlying physicochemical mechanisms involved in enhanced oil recovery and IFT reduction by low salinity water injection into heavy oil reservoir. IFT was measured as a function of...
State-of-the-art least square support vector machine application for accurate determination of natural gas viscosity
, Article Industrial and Engineering Chemistry Research ; Vol. 53, issue. 2 , 2014 , pp. 945-958 ; ISSN: 08885885 ; Arabloo, M ; Shokrollahi, A ; Zargari, M. H ; Ghazanfari, M. H ; Sharif University of Technology
Abstract
Estimation of the viscosity of naturally occurring petroleum gases is essential to provide more accurate analysis of gas reservoir engineering problems. In this study, a new soft computing approach, namely, least square support vector machine (LSSVM) modeling, optimized with a coupled simulated annealing technique was applied for estimation of the natural gas viscosities at different temperature and pressure conditions. This model was developed based on 2485 viscosity data sets of 22 gas mixtures. The model predictions showed an average absolute relative error of 0.26% and a correlation coefficient of 0.99. The results of the proposed model were also compared with the well-known predictive...
Evaluation of interfacial mass transfer coefficient as a function of temperature and pressure in carbon dioxide/normal alkane systems
, Article Heat and Mass Transfer/Waerme- und Stoffuebertragung ; Volume 51, Issue 4 , April , 2015 , Pages 477-485 ; 09477411 (ISSN) ; Keshavarz, P ; Ayatollahi, S ; Raoofi Jahromi, I ; Zolghadr, A ; Sharif University of Technology
Springer Verlag
2015
Abstract
CO2 gas injection is known as one of the most popular enhanced oil recovery techniques for light and medium oil reservoirs, therefore providing an acceptable mass transfer mechanism for CO2–oil systems seems necessary. In this study, interfacial mass transfer coefficient has been evaluated for CO2–normal heptane and CO2–normal hexadecane systems using equilibrium and dynamic interfacial tension data, which have been measured using the pendant drop method. Interface mass transfer coefficient has been calculated as a function of temperature and pressure in the range of 313–393 K and 1.7–8.6 MPa, respectively. The results showed that the interfacial resistance is a parameter that can control...
Solubility of CO2 and H2S in the ionic liquid 1-ethyl-3-methylimidazolium trifluoromethanesulfonate
, Article Journal of Natural Gas Science and Engineering ; Volume 30 , Volume 30 , 2016 , Pages 583-591 ; 18755100 (ISSN) ; Jalili, A. H ; Ghotbi, C ; Rashtchian, D ; Sharif University of Technology
Elsevier
2016
Abstract
The solubility of carbon dioxide and hydrogen sulfide gases in the ionic liquid 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([C2mim][OTf]) was measured at temperatures from (303.15-353.15) K and pressures up to about 3.0 MPa. The Henry's law constants were determined from the new experimental data, which in turn were used to derive the change of some thermodynamic functions of dissolution of the gases in that particular ionic liquid. The new experimental data were correlated by a combination of the extended Henry's law and Pitzer's model for the excess Gibbs energy. The average relative percent deviation (ARD%) of correlated molality values from experimental data are within...
Experimental investigation on CO2-light crude oil interfacial and swelling behavior
, Article Chinese Journal of Chemical Engineering ; 2017 ; 10049541 (ISSN) ; Ayatollahi, S ; Sharif University of Technology
Abstract
A systematic series of experiments are designed and performed including interfacial tension (IFT) measurements concomitant with Bond (BN, the ratio of gravity forces to capillary forces) and swelling/extraction measurements. Dynamic IFT, BN and swelling/extraction are measured as a function of pressure at temperatures of 30, 50 and 80°C. In addition, in the light of measured IFT the minimum miscibility pressure (MMP) of CO2 and light crude oil is determined based on a method called vanishing interfacial tension (VIT). The obtained results interestingly revealed that equilibrium IFT decreases linearly with pressure in two distinct pressure intervals while equilibrium BN shows an increasing...
Experimental investigation on CO2-light crude oil interfacial and swelling behavior
, Article Chinese Journal of Chemical Engineering ; Volume 26, Issue 2 , 2018 , Pages 373-379 ; 10049541 (ISSN) ; Ayatollahi, S ; Sharif University of Technology
Chemical Industry Press
2018
Abstract
A systematic series of experiments are designed and performed including interfacial tension (IFT) measurements concomitant with Bond (BN, the ratio of gravity forces to capillary forces) and swelling/extraction measurements. Dynamic IFT, BN and swelling/extraction are measured as a function of pressure at temperatures of 30, 50 and 80 °C. In addition, in the light of measured IFT the minimum miscibility pressure (MMP) of CO2 and light crude oil is determined based on a method called vanishing interfacial tension (VIT). The obtained results interestingly revealed that equilibrium IFT decreases linearly with pressure in two distinct pressure intervals while equilibrium BN shows an increasing...
Swelling behavior of heavy crude oil during injection of carbonated brine containing chloride anion
, Article Journal of Molecular Liquids ; Volume 276 , 2019 , Pages 7-14 ; 01677322 (ISSN) ; Zeinolabedini Hezave, A ; Ayatollahi, S ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Carbonated brine (CB) injection, known as one of the effective enhanced oil recovery processes, is highly dependent on the reservoir conditions (i.e. temperature and pressure) as well as the type of dissolved salt in aqueous solution. This study is aimed to investigate the influential parameters on the swelling of crude oil as the most important mechanism during CB injection. The swelling of crude oil in the presence of different CB solutions consisted of different salts such as KCl, NaCl, CaCl2 and MgCl2 with constant concentration of 15,000 ppm is studied using a high-pressure, high-temperature visual cell which measures the volume of drop using image processing software based on...
Prediction of erosive wear locations in centrifugal compressor using CFD simulation and comparison with experimental model
, Article Journal of the Brazilian Society of Mechanical Sciences and Engineering ; Volume 41, Issue 2 , 2019 ; 16785878 (ISSN) ; MomeniLarimi, M ; Ganji, B ; Ranjbar, A ; Sharif University of Technology
Springer Verlag
2019
Abstract
Erosive wear is one of the efficiency reduction causes in centrifugal compressors. The presence of suspended solid particles in the fluid causes deformations in different parts of the compressor, especially blades of the impeller. Therefore, erosion not only decreases the part lifetime by destruction of blades form, but also increases energy losses. For this reason, specifying the erosion locations and choosing a suitable material have an important effect on optimum functionality of the machine. In this paper, erosion locations of a compressor impeller by using computational fluid dynamics (CFD) in high temperature and pressure are attained and compared with experimental model. The...
Separation of CO2/CH4 through alumina-supported geminal ionic liquid membranes
, Article Journal of Membrane Science ; Vol. 455 , 2014 , pp. 229-235 ; ISSN: 03767388 ; Adibi, M ; Seifkordi, A. A ; Fazli, Y ; Sharif University of Technology
Abstract
Interesting properties of ionic liquids lead to their application as sub-component of membrane structures. Supported ionic liquid membranes (SILMs) are porous membranes whose pores are saturated with ionic liquids. Two ionic liquids, pr[mim]2[Tf2N]2 [1,3-di(3-methyl-imidazolium) propane bis(trifluoromethylsulfonyl) imide] and, h[mim]2 [Tf2N]2 [(1,6-di(3-methylimidazolium)hexane bis(trifluoromethylsulfonyl)imide)], were synthesized in our laboratory and stabilized on an alumina porous support. Permeability and permselectivity of carbon dioxide and methane using membranes containing these ionic liquids were then measured. The experiments were performed in the pressure range of 10-50kPa and...
Plasma core at the center of a sonoluminescing bubble
, Article Physical Review E - Statistical, Nonlinear, and Soft Matter Physics ; Volume 87, Issue 1 , 2013 ; 15393755 (ISSN) ; Sadighi Bonabi, R ; Sharif University of Technology
2013
Abstract
Considering high temperature and pressure during single bubble sonoluminescence collapse, a hot plasma core is generated at the center of the bubble. In this paper a statistical mechanics approach is used to calculate the core pressure and temperature. A hydrochemical model alongside a plasma core is used to study the bubble dynamics in two host liquids of water and sulfuric acid 85 wt % containing Ar atoms. Calculation shows that the extreme pressure and temperature in the plasma core are mainly due to the interaction of the ionized Ar atoms and electrons, which is one step forward to sonofusion. The thermal bremsstrahlung mechanism of radiation is used to analyze the emitted optical energy...
A comprehensive study on CO2 solubility in brine: Thermodynamic-based and neural network modeling
,
Article
Fluid Phase Equilibria
;
Volume 403
,
October
,
2015
,
Pages 153-159
;
03783812 (ISSN)
; Salami, H
; Taghikhani, V
; Robert, M. A
;
Sharif University of Technology
Elsevier
2015
Abstract
Phase equilibrium data are required to estimate the capacity of a geological formation to sequester CO2 . In this paper, a comprehensive study, including both thermodynamic and neural network modeling, is performed on CO2 solubility in brine. Brine is approximated by a NaCl solution. The Redlich-Kwong equation of state and Pitzer expansion are used to develop the thermodynamic model. The equation of state constants are adjusted by genetic algorithm optimization. A novel approach based on a neural network model is utilized as well. The temperature range in which the presented model is valid is 283-383K, and for pressure is 0-600bar, covering the temperature and pressure...
Kinetics of asphaltene aggregation phenomena in live oils
, Article Journal of Molecular Liquids ; Volume 222 , 2016 , Pages 359-369 ; 01677322 (ISSN) ; Rashidi, F ; Ghazanfari, M. H ; Mousavi Dehghani, S. A ; Sharif University of Technology
Elsevier
Abstract
The thorough knowledge of the asphaltene aggregation phenomena and pressure/temperature related kinetics is helpful for accurate prediction/control of the asphaltene issues in all facets of petroleum production/processing. However, characterizing the asphaltene aggregation phenomena in live oils at high pressure-high temperature conditions is not well discussed in the available literature. In this work, the asphaltene aggregation phenomena as well as the kinetics of aggregation at different levels of pressure and temperature are investigated in light and heavy live oils using high pressure microscope. The results are presented and discussed in terms of asphaltene onset pressure, aggregates...