فهرست مطالب

Chemical and Petroleum Engineering - Volume:52 Issue: 1, 2018
  • Volume:52 Issue: 1, 2018
  • تاریخ انتشار: 1397/03/31
  • تعداد عناوین: 9
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  • Akeem Olatunde Arinkoola *, Salawudeen Taofeeq Olakelan, Salam Kazeem Kolapo, Jimoh Monsurat Omoloa, Azeez Olatunji Gafar Pages 1-12
    Drilling cost optimization has always been an important issue in the petroleum industry. In order to save costs and create new markets for local materials, Ofo (D. micocarpum) and food gum (C. populnea) powders were evaluated in this study at high temperature as alternative to imported chemical additives in water based drilling fluid. The base mud composed of alkali beneficiated local clay, achi (B. eurycoma), corn and cocoanut fibers whose viscosity, yield point and gel strength fell short the recommended API standard from preliminary analysis. The two factors were combined using experimental design technique and mud properties optimized numerically using desirability function. At optimum conditions, the mud’s properties obtained include: Plastic viscosity, PV (18.4 ± 0.63 cp), Yield point, Yp (15.7 ± 0.9 lbf/100ft2), Fluid loss, FL (12.1 ± 0.37 ml) and 10 min Gel strength (5.6 ± 0.05 lbf/100ft2). These values are in good agreement with the API recommended standard. Both biopolymers exhibited high potential at low and moderate temperatures. However, food gum is thermally stable, a good rheology stabilizer and filtrate reducer up to the test temperature of 185 oF. The presence and nature of salts in solution influences differently the viscosity of the two bio-polymers.
    Keywords: API filtrate loss, Biopolymer, Experimental design, Gel strength, Optimization, Rheology
  • Mansour Jahangiri *, Shahram Alijani, Fatollah Salehirad Pages 13-21
    A high chlorinated alumina catalyst obtained by treating Pt/γ-Al2O3 (0.25 wt. % Pt) samples with two mixtures of CCl4/N2 and CCl4/N2/H2 was tested for the hydroisomerization of C6 alkane. The conversion of n-hexane feed was diluted with hydrogen performed with different H2/HC ratios at various temperatures, liquid hourly space velocities (LHSVs) and 3MPa total pressure. The catalyst introduced in the reactor displayed a fairly high initial activity, but conversion slowly declined with time on stream. Adding CCl4 to the hexane feed could not improve the stability with time on stream. The effects of temperature on conversion and isomer selectivity were studied at various H2/HC ratios and LHSVs. Superior conversion and selectivity were found for the catalyst at 160 ˚C and 120 ˚C at LHSV 1.2 h-1. Furthermore, effects of LHSV and low temperature were studied on conversion and product octane number derived from hexane isomerization, respectively. The highest octane number was observed at the low space velocity (1.2 h-1).
    Keywords: Catalyst, Chlorinated alumina, Isomerization, Light naphtha, Normal hexane
  • Elham Sadat Moosavi, Mahtab Gharibi *, Ramin Karimzadeh, Behnaz Asbaghi, Soulmaz Sayedshahabi, Sina Alizad, Majid Zare Pages 23-33
    This work investigates the effect of different conditions of PFO thermal cracking from two PFO samples on liquid, solid and gas product yield and asphaltene removal efficiency in a new designed experimental setup. No need to use a catalyst, simple operating system and experiment conditions, the ability to use water as a cheap carrier gas and high asphaltene extraction efficiency without the use of solvents are outstanding benefits of this method to upgrade PFO. The yields of the liquid, solid and gas products were compared in various operating conditions and the optimum experimental conditions were obtained. The results revealed the best thermal cracking condition of PFO in terms of liquid yield and asphaltene removal in this setup for samples. The optimum conditions were 390 and 380 °C for reactor temperature of PFO-1 and PFO-2, respectively; 150 °C for temperature of carrier gas and 100 ml/min for carrier gas flow rate. In these circumstances about 70 and 53 wt% of the liquid product, 25 wt% of the solid products, and 5 wt% of the gas product are generated while the asphaltene separation was reached about 95 and 96.5%.
    Keywords: Asphaltene, Naphthalene, Product yield, Pyrolysis fuel oil (PFO), Thermal cracking
  • Reza Khoshneshin, Saeid Sadeghnejad * Pages 35-47
    Determination of optimum location for drilling a new well not only requires engineering judgments but also consumes excessive computational time. Additionally, availability of many physical constraints such as the well length, trajectory, and completion type and the numerous affecting parameters including, well type, well numbers, well-control variables prompt that the optimization approaches become imperative;. The aim of this study is to figure out optimum well location and the best completion condition using coupled simulation optimization on an Iranian oil field located in southwest of Iran. The well placement scenarios are considered in two successive time intervals during of the field life, i.e., exploration and infill drilling phase. In the former scenario, the well-placement optimization is considered to locate the drilling site of a wildcat well, while the later scenario includes the optimum drilling location of a well is determined after 10-years primary production of nine production wells. In each scenario, two stochastic optimization algorithms namely particle swarm optimization, and artificial bee colony will be applied to evaluate the considered objective function. The net present value to drill production wells through the field life is considered as an objective function during our simulation-optimization approach. Our results show that the outcome of two population-based algorithms (i.e., particle swarm optimization and artificial bee colony) is marginally different from each other. The net present value of the infill drilling phase attains higher value using artificial bee colony algorithm.
    Keywords: Artificial bee colony, Coupled simulation-optimization, Infill drilling, Net present value, Particle swarm optimization, Well placement
  • Hajar Ghasemian Gorji, Behnaz Dahrazma * Pages 49-57
    Contamination of water resources with petroleum products is a serious environmental problem. The current study was carried out to investigate the effect of using raw and heat activated red mud (RM) as adsorbent to remove insoluble fraction of gasoline from aqueous solution. Some parameters such as pH, contact time, adsorbent dose and initial concentration were optimized in adsorption process to obtain the highest removal efficiency. Maximum removal of gasoline by raw and heat activated red mud at pH 8 and 7 were 90% and 92% respectively, during the contact time of 30 minutes, adsorbent dose of 50 g/L and 1% initial concentration of gasoline were the same for both adsorbents. Study of isotherm for raw and heat activated red mud showed high consistency with Langmuir and Freundlich isotherms, respectively. The kinetics of adsorption process was described by a pseudo-second-order model for both adsorbents. Experimental adsorption capacity of raw and heat activated red mud was achieved 0.7 and 0.66, respectively. According to the results, the adsorbents used in this study, have an appropriate efficiency for removal of the insoluble fraction of gasoline from aqueous solution.
    Keywords: Adsorption, Aqueous solution, Gasoline, Heat activation, Kinetics, Red mud
  • Majid Mohadesi *, Ghazal Pourghazi Pages 59-67
    In this study, NRTL and UNIQUAC thermodynamic models were used to predict the composition of ternary mixtures of solvents m/o/p-cresol water in organic and aqueous phases. Various solvents are used for the separation of cresols from water. In this study, methyl propyl ketone, methyl isopropyl ketone, methyl butyl ketone, and methyl isobutyl ketone solvents were investigated. Intermolecular interaction parameters were considered to be a function of temperature. The binary interaction parameters of water and cresols (m, o, or p) in the presence of each type of solvent were considered to be the same. Also, regardless of the type of cresol (m, o, or p), the parameters of binary interaction between water and each solvents were considered to be the same. The results proved the accuracy of the presented models, though the parameters of binary interaction parameters were considered to be the same. The root mean square deviation for NRTL and UNIQUAC models was 0.0086 and 0.0089, respectively.
    Keywords: Cresol, NRTL, Organic solvent, Thermodynamic models, UNIQUAC
  • Jagar Abdulazez Ali *, Karl Stephen Pages 69-80
    History matching is used to constrain flow simulations and reduce uncertainty in forecasts. In this work, we revisited some fundamental engineering tools for predicting waterflooding behavior to better understand the flaws in our simulation and thus find some models which are more accurate with better matching. The Craig-Geffen-Morse (CGM) analytical method was used to predict recovery performance calculations and it was simple enough which can be applied in a spreadsheet. In this study, the analytical approach of history matching was applied to a layered reservoir from a shallow marine deposit which was composed of different facies includes lower shoreface facies (LSF), middle shoreface facies (MSF) and upper shoreface facies (USF). Truncated Gaussian Simulation (TGS) is often used to stochastically distribute the facies in the geological model around a deterministic mean representation. The actual distribution is often hard to determine. Starting with the deterministic element of the facies distributions, corrections were made by matching the CGM method predictions to historical data. These corrections were amalgamated in the model and produced a much better history match. Further, the modifications were used to condition the stochastic simulator to provide a geologically more robust model that also matched history. The results showed that the variation of the total field production rate (FPR) between the deterministic model and history data was reduced by about 19.8% (from 21.52% to 1.73%) after applying history match analytically.
    Keywords: Craig-Geffen-Morse analytical method, History matching, Improving geological models, Waterflood performance, Uncertainty reduction
  • Melika Mostafavi, S. M. J. Mirazimi, Fereshteh Rashchi, F. Faraji, Navid Mostoufi * Pages 81-91
    Bioleaching was used to mobilize Cu, Zn and Ni from waste printed circuit boards (WPCBs) and eliminate hazardous metal species from these wastes. Pulp density (PD) and medium culture are two effective factors which have been optimized in this paper. The bacteria Acidithiobacillus ferrooxidans (A. ferrooxidans) and Acidithiobacillus thiooxidans (A. thiooxidans) and their mixture were grown and adapted in the presence of WPCBs and then used as bioleaching bacteria to solubilize metals from PCBs. The experimental results demonstrated that 15 g/L WPCB is the best solid concentration which can be tolerated by the bacteria. Comparing different inoculation ratios, Cu (86%), Zn (100%) and Ni (100%) were recovered after 25 days of bioleaching, which suggests that the rate of metal recovery is significantly influenced by PD. Kinetics of bioleaching reactions was investigated in this work and the shrinking core model (SCM) was used to describe the kinetics of the process of no pretreated WPCBs. A constrained multi-linear regression analysis using the least square technique was employed to determine the rate controlling mechanism in each operating condition. Based on the results, diffusion through solid product layer was the major controlling mechanism.
    Keywords: Bioleaching, Copper, Electronic scrap, Kinetics, Nickel, Zinc
  • Mahsa Okhovat, Hamidreza Norouzi, Navid Mostoufi * Pages 93-105
    Effect of interparticle force on the hydrodynamics of gas-solid fluidized beds was investigated using the combined method of computational fluid dynamics and discrete element method (CFD-DEM). The cohesive force between particles was considered to follow the van der Waals equation form. The model was validated by experimental results from literature in terms of bed voidage distribution and Eulerian solid velocity field. The results revealed that the incorporated model can satisfactorily predict the hydrodynamics of the fluidized bed in the presence of interparticle forces. Effect of interparticle force on the bubble rise characteristics, such as bubble stability, bubble diameter and bubble velocity, was investigated. It was shown that the emulsion voidage increases with increasing the interparticle force in the bed and it can hold more gas inside its structure. In addition, by increasing the interparticle force, size of bubbles and rise velocity of bubbles increase while the average velocity of particles decreases.
    Keywords: Discrete element method, Interparticle forces, Hydrodynamics, Bubble, Fluidization