University of IsfahanGas Processing Journal2322-32516120180101Plant-wide Simulation of an Integrated Zero-Emission Process to Convert Flare Gas to Gasoline1202290510.22108/gpj.2018.111048.1028ENMostafaJafariFaculty of Chemical Engineering, Urmia University of Technology, Urmia, Iran.SadafAshtabFaculty of Chemical Engineering, Urmia University of Technology, Urmia, IranAlirezaBehroozsarandFaculty of Chemical Engineering, Urmia University of Technology, Urmia, Iran.KamranGhasemzadehFaculty of Chemical Engineering, Urmia University of Technology, Urmia, IranDavid AWoodDWA Energy Limited
Lincoln, United KingdomJournal Article20180518The Gas to Gasoline (GTG) process includes conversion of natural, flare, and associated gas into synthetic fuels that can be compositionally upgraded and adjusted into different useful hydrocarbon fuels including gasoline, liquid petroleum gas (LPG), and fuel gas. Commonly, the GTG process involves three stages: 1) Synthesis gas (syngas) production unit 2) Methanol production unit 3) Methanol to Gasoline production unit (MTG). In this study, an integrated Flare Gas to Gasoline (FGTG) process for converting flare gas to gasoline, LPG and fuel gas is simulated using the Aspen HYSYS v. 8.8 simulator. The steam methane reforming (SMR) unit, the syngas to methanol unit, and the MTG unit are configured for simulation as an integrated FGTG process. In order to reduce carbon dioxide gas emissions to the atmosphere, a novel closed arrangement for the FGTG process (recycling configuration) is described and simulated. The simulation results demonstrate that by recycling all gas emissions, such as flare and off gas from the methanol and MTG units back into the process cycle, gasoline and LPG productivity can be increased on average by about 53% and 10%, respectively, compared to a base FGTG configuration that does not involve such recycling. The integrated simulation is supported by sensitivity analysis based on FGTG plants of various natural gas capacities (from 70,000 to 130,000 lb./hr.) as the adjustable (independent) variable and gasoline, LPG, and fuel gas selectivity as the dependent variables. Results of the simulation cases reveal that the total productivity of the integrated FGTG process could be increased in terms of flare gas mass flow, with the selectivity of products remaining approximately fixed for different plant capacities (i.e., at 75% for the gasoline product). Moreover, the utilities and energy consumption of the FGTG process is compared for several sensitivity cases. The results reveal that by increasing the capacity of the gas feed (natural gas mass flow) the Energy Index (i.e., total utilities consumption to product flow rate) decreased by about 8% and 47% in the base and recycling configurations, respectively. This finding suggests that an FGTG plant becomes more energy efficient at in higher-capacity plants.https://gpj.ui.ac.ir/article_22905_4533094aeaf2ade2cfaee0c77dd044a0.pdfUniversity of IsfahanGas Processing Journal2322-32516120180101Experimental Study of Chemical Absorption of CO2 in a Bench-Scale Spray Dryer Absorber21282285610.22108/gpj.2018.109349.1023ENLeilaKavoshiChemistry Department, NaghsheJahan Institute of Higher Education, Baharestan, Isfahan, Iran/
Chemical Engineering Department, University of Isfahan, Isfahan, Iran.AmirRahimiChemical Engineering Department, University of Isfahan, Isfahan, Iran.Mohammad SadeghHatamipourChemical Engineering Department, University of Isfahan, Isfahan, Iran.Journal Article20180129The removal of CO2 through chemical absorption in a bench-scale spray dryer absorber was investigated experimentally using the lime slurry as absorbent. The effect of important operating parameters on CO2 removal efficiency has been investigated; in selected ranges of operating parameters, increasing gas inlet temperature and absorbent concentration lead to permanent efficiency decline, increasing liquid to gas flow rate ratio and inlet gas humidity and lowering CO2 concentration have favored the removal efficiency. Adding Na(OH) solution to the absorbent increases its ability to absorb CO2 whiles decreases its tendency to produce final dried powder. It was found that adding 100 mL of Na(OH) solution with 1 mol/L concentration per each 1000 mL of lime slurry gives a removal efficiency of 70.5%. Other operating parameters were according to the following: Tg,in = 200 ○C, CA,in = 5 %(vol.), CB,in = 0.7 mol/L, (L/G)in = 0.025 mL/L, Hin=0.024 kg/kg and N=12600 rpm.https://gpj.ui.ac.ir/article_22856_e1c0187fbbc9f7c4fe82733e97489822.pdfUniversity of IsfahanGas Processing Journal2322-32516120180101Thermodynamic analysis of three combined power and refrigeration Systems based on a demand29402284210.22108/gpj.2018.110956.1026ENHoomanGolchoobianK.N. Toosi University of TechnologyMajidAmidpourK. N. Toosi University of TechnologyOmidPouraliK.N. Toosi University of TechnologyJournal Article20180513Three combined power and refrigeration system are introduced to compare and analyze for a defined demand and same fuel consumption based on thermodynamic parameters in a 24 hours period. Gas turbine and/or steam turbine are used for power generation and also ejector refrigeration cycle is used to produce cooling. These three systems are named as GER, SER and GSER. The results of three systems are compared and it’s shown that SER has so much lower cogeneration efficiency than two other systems. GSER produces 284 MWhr per year more power than GER with the same fuel consumption that can easily cover the additional capital cost of the system. Moreover, exergy efficiency of GSER is 12% higher than GER and its cogeneration efficiency is 8% higher than GER too. So, between these three systems we would recommend GSER because of better performance like higher exergy and energy efficiency and also better conformity with our demandhttps://gpj.ui.ac.ir/article_22842_9e63c64ff079f33d1d8e1dd7315b170f.pdfUniversity of IsfahanGas Processing Journal2322-32516120180101Advanced Exergoeconomic Analysis of C3MR, MFC and DMR Refrigeration Cycles in an Integrated Cryogenic Process41712282510.22108/gpj.2018.111251.1032ENVahidGhazizadehMechanical Engineering, K. N. Toosi University of Technology, Tehran, IranBahramGhorbaniAmol University of Special Modern TechnologiesRezaShirmohammadiDepartment of Renewable Energies and Environment, Faculty of New Sciences & Technologies, University of Tehran, Tehran, IranMehdiMehrpooyaDepartment of Renewable Energies and Environment, Faculty of New Sciences & Technologies, University of Tehran, Tehran, IranMohammad HoseinHamediMechanical Engineering, K. N. Toosi University of Technology, Tehran, IranJournal Article20180527C3MR, MFC, and DMR processes in an integrated LNG-NGL-NRU structure are investigated using the conventional and advanced exergy and exergoeconomic analyses. The results of advanced exergy analysis reveal that in most of the equipment, the highest amount of irreversibility is occurred because of endogenous exergy destruction. In C3MR process, compressor C5 with 9730 kW; in MFC process, compressor C1 with 6342 kW; and in DMR process, compressor C3 with 10008 kW; have the most amount of avoidable endogenous exergy destruction in comparison with the other equipment. According to the advanced exergoeconomic analysis, the amount of endogenous part of exergy destruction cost and investment cost is higher than the exogenous part for most of the equipment, representing that interactions among the equipment is not considerable. Compressors have the highest amount of avoidable endogenous investment cost in all of the processes. Furthermore, in C3MR process, HX2 heat exchanger with 1121 $/h; in MFC process, compressor C1 with 450 $/h; and in DMR process, HX3 heat exchanger with 3955 $/h; have the most amount of avoidable endogenous exergy destruction cost. Based on total costs defined for the equipment, in C3MR process, HX2 heat exchanger with 1126 $/h should be modified. In MFC process, compressor C1 with 504.7 $/h should be considered. In DMR process, HX3 heat exchanger with 3963 $/h should be improved its performance. Finally, sensitivity analysis as well as validation have been conducted, and three different strategies are used to reduce the cost of avoidable exergy destruction of system equipment.https://gpj.ui.ac.ir/article_22825_71fdaf02a1d432067d8f30107e3a8c04.pdfUniversity of IsfahanGas Processing Journal2322-32516120180101Effect of Geometrical Parameters on the Flow Pattern and Performance of Gas-Particle Separators: A Numerical Study72842293310.22108/gpj.2018.112320.1037ENMehdiMiansari Department of Mechanical engineering, Qaemshahr Branch, Islamic Azad University, QaemshahrGhasemNajarian DarounkolaieDepartment of Mechanical engineering, Qaemshahr Branch, Islamic Azad University, QaemshahrBehnamAminiDepartment of Mechanical engineering, Qaemshahr Branch, Islamic Azad University, QaemshahrJournal Article20180801Air and gas pollution has become a critical problem endangering species life worldwide. Among all technologies proposed to solve this problem, separators including cyclones have attracted tremendous attention towards separation of airborne and solid particles from air and gases due to their simplicity of construction, low operating costs and flexibility in tolerating hard conditions. In this study, a numerical investigation of solid particle separation in gas-particle cyclones is presented. The Reynolds stress turbulence model (RSM) is employed to simulate a strongly swirling turbulent air flow along with the discrete phase model (DPM) to trace the particles. A wide range of geometrical parameters is studied to find out how they affect the flow field pattern and particle separation in cyclones, hence the cyclone performance. It is shown that the pressure drop and the tangential velocity decrease with inlet angle increment. In addition, the static pressure increases due to a small diameter reduction originating from the reduction in cone angle. The static pressure is significantly reduced in the cyclone with higher cone height when the axial velocity changes are not noticeable. This parametric study developed based on a numerical model, can have a great potential for design and fabrication of cyclones used in gas-solid separation industries.https://gpj.ui.ac.ir/article_22933_b9125c77930b86578c20c84d1e12b8dc.pdfUniversity of IsfahanGas Processing Journal2322-32516120180227Development and Optimization of an Integrated Process Configuration for IGCC Power Generation Technology with a Fischer-Tropsch Fuels from Coal and Biomass851082336610.22108/gpj.2018.112760.1038ENMalekShariati NiassarRenewable Energies and Environmental Department, Niroo Research Institute, Tehran, IranJournal Article20180901The conversion of coal into high-quality fuels is carried out through gasification, syngas production and the process of Fischer-Tropsch. Additionally, produced syngas derived from coal gasification only can generate power and heat in a combined cycle power plant. In order to combine these two methods together in an integrated process at the same time, it is necessary to use part of the produced gas for the production of heat and power, and the other part for the production of liquid fuel. As a result, this new and integrated process will consist of three major parts: "coal gasification", "power and heat generation" and "production of liquid fuel". The purpose of this study is by consideration of an integrated gasification combined cycle (IGCC) plant with input feed of coal, an integrated system of "Combined heat and power as well as liquid fuel of Fischer-Tropsch", called in this research CHPF is designed, and the optimum amounts of production of the power, heat and liquid fuel are provided at a certain scale of the feedstock. Thus, the various parts of this integrated process is designed conceptually, and simulated and integrated with Aspen software; then an objective function is defined to maximize the revenue from the sale of process products (power and liquid fuels). To ensure the accuracy of the results, the sensitivity analysis tool is used; and the simulation and design results are compared with an experimental work, indicating that the difference in results is about 4%.https://gpj.ui.ac.ir/article_23366_03442eeceaa14b6d425984a1f2a9fd1d.pdf