University of IsfahanGas Processing Journal2322-32512120140101Vol.2, No.1, 2014012343010.22108/gpj.2014.23430ENJournal Article20190306https://gpj.ui.ac.ir/article_23430_9532813d2a4ada61c2b0a5c8be48a3a5.pdfUniversity of IsfahanGas Processing Journal2322-32512120140101Application of Zeotype SAPO-34 Molecular Sieve as a Selective Adsorbent for Separation of Ethylene from Ethane172017010.22108/gpj.2014.20170ENShohrehFatemiSchool of Chemical Engineering, College of Engineering, University of TehranMojtabaMasoudi-NejadSchool of Chemical Engineering, College of Engineering, University of TehranJournal Article20160615The<br /> process of ethylene production from ethane dehydrogenation is one of the<br /> interesting processes in the field of conversion the petroleum light gases to<br /> the valuable products. In this process, the outlet gaseous product is a<br /> combination of ethylene, ethane and hydrogen. Effective separation techniques<br /> are required for separation of ethylene from unreacted ethane. Here a new<br /> adsorbent approach is introduced for separation of ethylene from ethane. The<br /> adsorbent is a kind of zeolite- like molecular sieve from<br /> silico-alumino-phosphate group (SAPO-34) which is previously synthesized and<br /> studied in the adsorption tests of ethane and ethylene. The equilibrium<br /> adsorption experiments are performed in a static batch adsorption apparatus at<br /> various moderate pressures and room temperature to evaluate the adsorption<br /> capacity and selectivity toward ethylene against ethane. A high tendency of<br /> SAPO-34 towards ethylene and the ethylene/ethane selectivity from 2 to 3 fold<br /> in the pressure range of 200 to 800 kPa is observed, confirming the potential<br /> application of SAPO-34 as an adsorbent in the adsorption process for separation<br /> of ethylene and ethane. https://gpj.ui.ac.ir/article_20170_eb7137f9c9b71eaede32deb0dab4e056.pdfUniversity of IsfahanGas Processing Journal2322-32512120140101Integrated Analysis of Choke Performance and Flow Behaviour in High-Rate, Deviated Gas-Condensate Wells8182017110.22108/gpj.2014.20171ENMohammad HosseinHeidari SureshjaniIOR Research Institute, Tehran, IranAhmadLakDepartment of Chemical Engineering, Faculty of Petroleum, Gas and Petrochemical Engineering, Persian Gulf University, Bushehr, IranShahriarOsfouriDepartment of Chemical Engineering, Faculty of Petroleum, Gas and Petrochemical Engineering, Persian Gulf University, Bushehr, IranRobabChahshooriDepartment of Petroleum Engineering, Faculty of Petroleum,Gas and Petrochemical Engineering, Persian Gulf University, Bushehr, IranRezaAzinDepartment of Petroleum Engineering, Faculty of Petroleum,Gas and Petrochemical Engineering, Persian Gulf University, Bushehr, IranShahabGeramiIOR Research Institute, Tehran, IranJournal Article20160615 Understanding the flow behaviour in a<br /> gas well is crucial for future production strategies, obtaining bottomhole<br /> conditions from wellhead production data, analyzing production data and<br /> estimating reservoir properties. In this work, the pressure profile and flow<br /> regime are studied on four wells of a multi-well, multi-layer gas-condensate<br /> reservoir, producing at high rate. The wells are deviated and cased-holes, with<br /> the gas flowing through tubing to the wellhead. Here, a comprehensive quality<br /> assessment of data is presented. An algorithm is proposed to model wellhead<br /> chokes and determine production rates of individual wells from overall,<br /> commingled daily flow rates. The pressure profile and flow regime were<br /> determined in each well through back-calculation and nodal analysis. The<br /> bottomhole pressure is predicted. The best correlations are selected by<br /> comparing the model results with reported production logging tool (PLT) data.<br /> The rates of produced condensate and water (equivalent to gas) and their PVT<br /> properties, e.g. API of condensate, had little impact on choke calculations,<br /> which is due to high flow rate gas. The flow is shown to be gas-like at the<br /> bottom, which turns to mist flow near the wellhead. Liquid holdup is subject to<br /> the wellhead pressure and well flow rate. It decreases with an increase in<br /> wellhead pressure and gas flow rate. The findings here can be extended to other<br /> wells in the same reservoir, which can introduce guidelines for gas-condensate<br /> well modeling.   https://gpj.ui.ac.ir/article_20171_97c22ecbad8d655d7eeaf3d0055c1550.pdfUniversity of IsfahanGas Processing Journal2322-32512120140101An Effective Iterative Algorithm for Modeling of Multicomponent Gas Separation in a Countercurrent Membrane Permeator19312017210.22108/gpj.2014.20172ENMasoumehMoheb ShahrestaniDepartment of Chemical Engineering, Faculty of Engineering, University of Isfahan, IranAmirRahimiJournal Article20160615 A model is developed for separation of<br /> multicomponent gas mixtures in a countercurrent hollow fiber membrane module.<br /> While the modelâs solution in countercurrent module usually involves in a time<br /> consuming iterative procedure, a proper initial guess is proposed for beginning<br /> the calculation and a simple procedure is introduced for correcting the<br /> guesses, hereby the CPU time is decreased essentially. The modelâs predictions<br /> are compared with the experimental data and a good agreement is achieved. By<br /> using data taken from a LAB unit in Isfahan, the proposed model is applied to<br /> investigate the feasibility of membrane process for hydrogen separation in this<br /> unit. It is revealed that a high hydrogen purity and recovery could be achieved<br /> in the permeate stream, while the required area increases at higher stage cut<br /> or higher permeate pressure.   https://gpj.ui.ac.ir/article_20172_06577becdffcb8c28e36aec169912fcd.pdfUniversity of IsfahanGas Processing Journal2322-32512120140101The Mathematical Method and Thermodynamic Approaches to Design Multi-Component Refrigeration used in Cryogenic Process Part II: Optimal Arrangement32392039810.22108/gpj.2014.20398ENMostafaMafiDepartment of Mechanical Engineering, Imam Khomeini International University, Qazvin, IranBahramGhorbaniDepartment of Energy System Engineering K.N.ToosiGholam RezaSalehiEnergy System Engineering Department, K. N. Toosi University of Technology, IranMajidAmidpourK. N. Toosi University of TechnologySeyed MojtabaMousavi NayenianEnergy System Engineering Department, K. N. Toosi University of Technology, IranJournal Article20161004 <br /> <br />A refrigeration cycle is a chain of various pieces of equipment including compressors, condensers, evaporators, and expansion devices each of which takes on a particular thermodynamic process duty in the cycle that eventually results in the production of the required refrigeration. The results of optimized mixed refrigerant cycles (MRCs) in Part I show that the configuration of MRC is an effective parameter in power consumption. In spite of simplicity of MRCs machinery configuration in comparison with a conventional cascade cycle, it is possible to imagine different configurations, providing the process required refrigeration, for these cycles. But the question here is how to find a configuration taking advantage of the existing complicated interactions between low temperature process and refrigeration cycle so that the maximum efficiency and the best functionality will be guaranteed. In this paper, based on the success of the systematic method proposed in part I for the optimal selection of refrigerant composition and operating pressures, the method is extended to give optimal arrangement of the cycle components. An illustrative example is presented to show how the proposed method can be utilized in order to achieve the optimal MRC configuration. <br /> <br /> https://gpj.ui.ac.ir/article_20398_72443c664800ec634abe3706dd5512d7.pdfUniversity of IsfahanGas Processing Journal2322-32512120140101A Unified Approach for Quality Control of Drilled Stem Test (DST) and PVT Data40502017410.22108/gpj.2014.20174ENShahabGeramiEOR Institute, National Iranian Oil Company, Tehran, IranMahboobehKiani ZakheradiDepartment of Chemical Engineering, Faculty of Petroleum, Gas and Petrochemical Engineering, Persian Gulf University, Bushehr, IranRezaAzinDepartment of Petroleum Engineering, Faculty of Petroleum, Gas, and Petrochemical Engineering, Persian Gulf University, Bushehr, IranShahriarOsfouriDepartment of Chemical Engineering, Faculty of Petroleum, Gas and Petrochemical Engineering, Persian Gulf University, Bushehr, IranJournal Article20160615Finding a representative fluid in a hydrocarbon reservoir is crucial for integrated reservoir management. In this study, a systematic approach for screening and selecting consistent fluid samples in a reservoir was developed. The model integrated quality control (QC) of well conditioning before sampling, QC of PVT data, thermodynamic modeling and compositional gradient within a reservoir. Well and separator conditioning were examined as essential steps before sampling at equilibrium conditions. Sampling criteria were deduced according to available data, sampling standards, and tolerance of field measurement devices. Then, PVT data of consistent fluid samples were carefully screened for efficient phase behavior studies. This model suggests that thermodynamic modeling and equation of state (EOS) tuning be performed on screened fluids using only consistent experimental data. The proposed model was implemented on PVT samples of a supergiant gas condensate reservoir in the Middle East. Results show that only 10% of collected samples are at equilibrium, good candidates for PVT studies. Also, ±0.1% change in composition of C12+ causes ±300 psia change in dew-point pressure, revealing no substantial difference between validated samples for the reservoir under study, and one representative fluid suffices throughout the reservoir.https://gpj.ui.ac.ir/article_20174_04137f7bc697866846da432261c3f1c9.pdfUniversity of IsfahanGas Processing Journal2322-32512120140101Optimal Synthesis of a Cascade Refrigeration System of LNG Through MINLP Model for Pure Refrigerant Cycles51682017510.22108/gpj.2014.20175ENSeyed MostafaMousavi NaeynianDepartment of Mechanical Engineering, K. N. Toosi University of TechnologyMajidAmidpourDepartment of Mechanical Engineering, K. N. Toosi University of TechnologyMeysamKamalinezhadDepartment of Mechanical Engineering, K. N. Toosi University of TechnologyJournal Article20160615 liquefied natural gas (LNG) is the most<br /> economical way of transporting natural gas (NG) over long distances.<br /> Liquefaction of NG by using vapor compression refrigeration system requires<br /> high operating and capital cost. Due to lack of systematic design methods for<br /> multistage refrigeration cycles, the conventional approaches of determining<br /> optimal cycle configuration are mostly based on trial-and-error and are very<br /> time consuming. Here a new Mixed Integer Non-Linear Programming (MINLP) model<br /> is introduced for selecting optimal synthesis of refrigeration system which<br /> would reduce both the OPEX and CAPEX of a LNG plant through Pinch technology. A<br /> superstructure of a complex refrigeration system is developed to select and<br /> optimize the key decision variables in refrigeration cycles (i.e. partition<br /> temperature, compression configuration, refrigeration features, refrigerant<br /> flow rate). This method reduces calculation time and increases design options<br /> that could be mounted over a multistage refrigeration cascade. Here a program<br /> (LNG-Pro) is developed that integrates the VBA, Refprop and Excel MINLP Solver<br /> to automate the methodology. Design of an LNG plant is described to illustrate<br /> advantages in adopting this method. Conceptual diagrams of pinch technology are<br /> shown to visualize the stepwise optimization procedure of compressorâs<br /> shaftwork. The proposed cascade by this method reduces compressor shaftwork of<br /> an LNG cascade from 1255 Kj/Kg to 1141.9Kj/Kg. https://gpj.ui.ac.ir/article_20175_5c76606cc7ea363fbd68b94b374f8f6f.pdf