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Chemical and Petroleum Engineering - Volume:50 Issue: 2, Feb 2017

Journal of Chemical and Petroleum Engineering
Volume:50 Issue: 2, Feb 2017

  • تاریخ انتشار: 1395/12/07
  • تعداد عناوین: 8
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  • Atieh Eskandari, Mansoor Anbia, Mansour Jahangiri, Fariba Mohammadi Nejati Pages 1-7
    Silicon and aluminum sources are most important reactants in the synthesis of zeolite. The use of the silicon source has an important effect on the crystallization of zeolites. Also, it can change the properties of the end product. This work reports the influence of three common commercial silica sources such as colloidal silica (Ludox AM-30), fumed silica and water glass on the crystallinity of NaX zeolite by hydrothermal method, also the adsorption of carbon dioxide on these samples have also been studied. The synthesized samples from different sources are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier transformin frared (FT-IR) and nitrogen adsorption–desorption analysis. The sample obtained by fumed silica, colloidal silica and water glass is NaX phase. The percentage of crystallinity and surface area increased in the sequence: water glass
    Keywords: Adsorption, Characterization, NaX zeolite
  • Kamyar Movagharnejad, Soraya Ghanbari Pages 9-17
    Numerous empirical correlations exist for the estimation of crude oil viscosities. Most of these correlations are not based on the experimental and field data from Iranian geological zone. In this study several well-known empirical correlations including Beal, Beggs, Glasso, Labedi, Schmidt, Alikhan and Naseri were optimized and refitted with the Iranian oil field data. The results showed that the Beal and the Labedi methods were not suitable for estimation of the viscosity of the Iranian crudes, while the Beggs, Glasso and Schmidt methods gave reasonable results. The Naseri’s correlation and their present method proved to be the best classical methods investigated in this study. Two new intelligent methods to predict the viscosity of Iranian crudes have also been introduced. The study also showed that the neural network and SVM give much better results comparing to classical correlations. It is claimed that this study may provide more exact results for the prediction of Iranian oil viscosity.
    Keywords: Dead oil, Empirical correlation, Neural network, SVM, Viscosity
  • Saini Dayanand Pages 19-27
    Parachor based expressions (basic and mechanistic) are often used to model the experimentally observed pressure dependence of interfacial tension (IFT) behaviors of complex supercritical carbon dioxide (sc-CO2) and crude oil mixtures at elevated temperatures. However, such modeling requires various input data (e.g. compositions and densities of the equilibrium liquid and vapor phases, and molecular weights and diffusion coefficients for various components present in the system). In the absence of measured data, often phase behavior packages are used for obtaining these input data for performing calculations. Very few researchers have used experimentally measured input data for performing parachor based modeling of the experimental IFT behaviors of sc-CO2 and crude oil systems that are of particular interest to CO2 injection in porous media based enhanced oil recovery (EOR) operations.
    This study presents the results of parachor based modeling performed to predict pressure dependence of IFT behaviors of a complex sc-CO2 and crude oil system for which experimentally measured data is available in public domain. Though parachor model based on calculated IFT behaviors shows significant deviation from the measured behaviors in high IFT region, difference between the calculated and the experimental behaviors appears to vanish in low IFT region. These observations suggest that basic parachor expression based calculated IFT behaviors in low IFT region follow the experimental IFT behaviors more closely.
    An analysis of published studies (basic and mechanistic parachor expressions based on modeling of pressure dependence of IFT behaviors of both standard and complex sc-CO2 and crude oil systems) and the results of this study reinforce the need of better description of gas-oil interactions for robust modeling of pressure dependence of IFT behavior of these complex systems.
    Keywords: CO2 injection in porous media, CO2-EOR, storage, CO2, oil interactions, Gas-oil interfacial tension, Parachor model, Miscibility
  • Reza Rooki Pages 29-35
    Underbalanced drilling as multiphase flow is done in oil drilling operation in low pressure reservoir or highly depleted mature reservoir. Correct determination of the pressure loss of three phase fluids in drilling annulus is essential in determination of hydraulic horsepower requirements during drilling operations. In this paper the pressure loss of solid-gas-liquid three-phase fluids flow in inclined annulus was estimated using artificial neural network (ANN). Experimental data which are available in the literature were used for design of ANN. Pressure loss as output of ANN, was estimated from five effective parameters as inputs of ANN including gas and liquid superficial velocities, the inclination from horizontal, rate of penetration (ROP), pipe rotation speed (RPM). The correlation coefficient between predicted and experimental value for train and test data is 0.998 and 0.997 respectively.The root mean square error (RMS) and average absolute percent relative error (AAPE) for train data are 0.0082 and 2.77% and for test data, they are 0.0108 and 3.68 % respectively. The reliable results showed the high ability of artificial neural network for estimating pressure loss of three phase flow in annulus.
    Keywords: Underbalanced drilling, Pressure loss, Three-phase flow, ANN, Annulus
  • Zeinab Salehi, Bahareh Kianpour, Akram Ebrahimi, Shohreh Fatemi Pages 37-45
    In this research graphene oxide was synthesized by two methods. These methods were achieved by changing the improved Hummers’ and modified Hummers’ methods. Structure of graphene oxide was characterized by scanning electron microscopy (SEM) images, X-ray diffraction (XRD) patterns, Raman spectroscopy and Fourier transform infrared (FTIR) spectra. According to SEM image, the thickness of graphene oxide sheets prepared by improved Hummers’ method is about 66 nm. In improved Hummers’ method excluding NaNO3 from reacting gel and performing reaction in a 9:1 volume ratio of concentrated H2SO4/H3PO4 mixture improved the oxidation process by elimination of toxic gases, finally the prepared GO contains well-oxidized carbon materials. XRD results implied more oxidation for synthesized GO by improved Hummers’ based method. Importance of graphite source was shown in synthesis of pure GO. Two sources of graphite supplied by Daejung and Fluka Companies were used to synthesis GO in improved Hummers’ method. According to SEM images and XRD patterns, the graphite source prepared by Fluka Co. was more efficient towards production of pure GO than other graphite source. The results also indicated that temperature and mixing condition are two important factors for synthesis of GO.
    Keywords: Graphite source, Graphene oxide, Operating condition, Synthesis
  • Taleb Zarei, Jamshid Khorshidi, Rahbar Rahimi, Ali Zarei Pages 47-52
    In the present study, experimental investigations about the hydrodynamics of the conical cap tray (ConCap tray) have been carried out. The ConCap tray is an innovative and novel type of cap trays. The effect of the different weir height (2.5, 5 and 7 cm) on the weeping, entrainment and the total pressure drop for the ConCap tray was measured, compared and correlated. The hydraulic experiments were carried out in an industrial scale simulator rig with an inner diameter of 1.2 m which has two test trays (ConCap tray) and two chimney trays. It was found that the weir height affects only on the pressure drop. The recommended weir height for the ConCap tray must be 2.5 cm because of observed spray flow regime on the tray and experimental results in different weir height which shows no effect on the weeping and entrainment rates. Moreover, the hydraulic behavior of the tray in the lower operating limits was also investigated.
    Keywords: eywords Conical gap tray, Hydrodynamic, Weeping, Entrainment, Weir height
  • Reza Zarghami, Hooman Ziaei Halimejani, Navid Mostoufi Pages 53-60
    Online detection of hydrodynamics of gas-solid fluidized bed was characterized using pressure fluctuations by cross recurrence plot (CRP) and cross recurrence quantification analysis (CRQA). Experiments were conducted in a lab scale fluidized bed of various particle sizes 150 μm, 280 μm and 490 μm at different gas velocities. Firstly, pattern changes of cross recurrence plot were discussed and then reference states was selected. Afterwards, cross average diagonal line (CLave) of other states corresponding to reference states were obtained. It was found that cross average diagonal line of non-normalized data initially decreases and then increases with increasing the gas velocity. When the signal is initially normalized, cross average diagonal line does not change with the superficial gas velocity. It was concluded that cross average diagonal line could be used for detecting small changes of particle size and if a proper reference state is chosen, it can be perceived as a powerful index for detecting changes in the size of particles in a fluidized bed.
    Keywords: Cross recurrence quantification analysis, Fluidized bed, Cross average diagonal line, Pressure fluctuations, Online detection
  • Hossein Ahamdi Danesh Ashtiani, Hamid Abdollah Zargar Pages 61-72
    Utilization of fossil fuel for supplying of requires energy of desalination systems is common. On the other hand, solar energy is one of the high-grade energies in the world that can be found specifically in hot weather places. Therefore, utilization of solar energy for operation of desalination systems will reduce greenhouse gases and is a good alternative way. Common exergy analysis method (stream wise) uses input and output exergy of streams to calculate the efficiency and exergy loss. Another exergy analysis method, named “Sink & Source”, is illustrated in the present study. The Stream wise method usually computes efficiency of systems as higher than a reliable value. For example, the computed exergy efficiency of presented high capacity MED desalination system is 88.63%, while this value is estimated about 1.04% from the new method. The uselessness of the traditional method for analyzing presented low-capacity MED desalination system is also shown. For example, the computed exergy efficiency of a low-capacity desalination system was 97.51%, while a value of 42.57% was obtained from the new method. A solar field and a solar heating system are suggested for presented high capacity and low capacity MED, respectively. Furthermore, an economic analysis of afore said desalination system is presented.
    Keywords: Exergy analysis method, Solar energy, MED desalination system, Stream wise, Sink, source