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Kinetics, experimental and simulation studies of Chinese Hamster Ovary cell growth in a packed-bed bioreactor
, Article World Applied Sciences Journal ; Volume 15, Issue 11 , 2011 , Pages 1568-1575 ; 18184952 (ISSN) ; Tabandeh, F ; Zomorodipour, A. R ; Mohammad-Beigi, H ; Ebrahimi, S ; Habib Ghomi, H ; Sharif University of Technology
2011
Abstract
To figure out the relationship between nutrient deprivation and cell growth, simulation can be effective. In the present work, the growth of Chinese Hamster Ovary (CHO) cells was simulated based on stoichiometric and kinetics calculations. The simulation results were compared to the experimental data from a packed-bed bioreactor and a good agreement was observed. The kinetic parameters (K Glc, K Amn, K Lact and μ Max) were optimized by a genetic algorithm method using stoichiometric parameters (Y X/Glc, Y X/Amm, and Y Lac/Glc). The stoichiometric and kinetic parameters were used in the simulation to study the growth of CHO cells. The concentrations of the toxic by-products, ammonium and...
Bed moisture estimation by monitoring of air stream temperature rise in packed-bed solid-state fermentation
, Article Chemical Engineering Science ; Volume 61, Issue 17 , 2006 , Pages 5654-5663 ; 00092509 (ISSN) ; Roostaazad, R ; Mitchell, D. A ; Miranzadeh, M ; Bozorgmehri, R ; Safekordi, A ; Sharif University of Technology
2006
Abstract
We develop a method for predicting the moisture content of the fermenting solids in an intermittently mixed packed-bed bioreactor on the basis of measurements of the inlet and outlet gas stream temperatures and the assumption that both the gas streams are saturated with water vapor. This method can be used to estimate when an intermittently mixed packed bed should be mixed and how much water should be added during the mixing event. The predictions were experimentally verified for the growth of Aspergillus niger on wheat bran in a thin packed bed. We show that the application of a controller based on our estimation method would have led to adequate moisture control, with significant errors in...
Transesterification of waste cooking oil to biodiesel using KOH/γ-Al2O3 catalyst in a new two-impinging-jets reactor
, Article Industrial and Engineering Chemistry Research ; Vol. 53, Issue. 31 , 2014 , Pages 12238-12248 ; ISSN: 08885885 ; Molaei Dehkordi, A ; Sharif University of Technology
Abstract
In this article, the transesterification of waste cooking oil (WCO) to biodiesel fuel (BDF) has been studied using KOH loaded on millimetric γ-Al2O3 particles in a novel type of two-impinging-jets reactor (TIJR). The effects of various parameters such as KOH loading (wt %), catalyst loading, and methanol-to-oil molar ratio on the BDF yield were studied. The catalyst particles with a KOH loading of 25 wt % at appropriate reaction conditions (i.e., catalyst loading = 4 wt % and methanol-to-oil molar ratio = 15:1) and at 65 °C were used in the TIJR. The influences of various operating and design parameters such as jet Reynolds number value, feed flow rate, jet diameter, and the internozzle...
Development and verification of a model to describe an immobilized glucose isomerase packed bed bioreactor
, Article Biochemical Engineering Journal ; Volume 40, Issue 2 , 2008 , Pages 328-336 ; 1369703X (ISSN) ; Roostaazad, R ; Sharif University of Technology
2008
Abstract
In this paper, the performance of immobilized packed bed glucose isomerase enzyme was mathematically modeled. A modified Michaelis-Menten type relation was used to describe the enzyme kinetics. Mass transfer inside the biocatalyst particle and through the bed column was analyzed simultaneously. Using measured data, physicochemical properties including diffusivity, viscosity and density of sugar solutions were correlated with its concentrations and were used to provide precision in solving the set of model equations. Model equations were solved using the Runge-Kutta and Gauss-Seidel algorithms and finite difference numerical method in MATLAB environment. Model output was used to demonstrate...
Modeling of sorption enhanced steam methane reforming in an adiabatic packed bed reactor using various CO2 sorbents
, Article Journal of Environmental Chemical Engineering ; Volume 9, Issue 5 , 2021 ; 22133437 (ISSN) ; Abbas, S. Z ; Maqbool, F ; Ramirez Solis, S ; Dupont, V ; Mahmud, T ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
A 1-D heterogeneous model of sorption-enhanced steam methane reforming (SE-SMR) process in a packed bed reactor consisting of nickel catalyst well mixed with CO2 sorbent particles is investigated for three types of common sorbents. The performance of SE-SMR process is studied under low medium pressure conditions (3 – 11 bar) to find the optimum operating conditions. Optimal CaO sorption corresponding to 82% CH4 conversion and 85% H2 purity is found at 900 K, 3 bar, 3.5 kgm−2s−1 and S/C of 3.0. In contrast, lithium zirconate (LZC) and hydrotalcite (HTC) sorbents exhibited best sorptions under the operating conditions of 773 K, 5 bar and S/C of 3 with CH4 conversion of 91.3% and 55.2%, and H2...
Synthesis of SiOC/Al2O3 nano/macro composites through PDC method; investigation of potentials as layers of a packed bed reactor membrane
, Article Ceramics International ; Volume 46, Issue 11 , 2020 , Pages 19000-19007 ; Paryab, A ; Rahmani, S ; Akbari, M ; Sarpoolaky, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Thanks to a wide range of pore sizes by nano/macro composites of SiOC/Al2O3, such composites can serve as different layers of the structure of Packed Bed Reactor Membranes (PBRM). In the present study, the Polymer-Derived Ceramics method (PDC) has been used to synthesize nano/macro structures. Firstly, the effect of toluene as an extra carbon source on structure and microstructure of SiOC glass-ceramics was evaluated, such that, 4% (Vol) toluene was recognized as the proper amount to facilitate the synthesis of β-SiC at 1300 °C proved by XRD, Raman spectroscopy, and HR-TEM. Moreover, the presence of micro/meso-porosities was assessed by BET and TEM, indicating the capability of SiOC to serve...
Photocatalytic decomposition of direct red 16 and kinetics analysis in a conic body packed bed reactor with nanostructure titania coated Raschig rings
, Article Chemical Engineering Journal ; Volume 151, Issue 1-3 , 2009 , Pages 295-301 ; 13858947 (ISSN) ; Asgari, M ; Soleymani, A. R ; Taghavinia, N ; Sharif University of Technology
2009
Abstract
A conic body packed bed reactor, internally irradiated with a UV-C lamp and equipped with circulating upflow stream was employed to investigate the decomposition of a widely used azo dye, direct red 16, in water. The synthesized nanostructure TiO 2 photocatalyst particles were immobilized on the surface of transparent Raschig ring packings. Solutions with initial concentration of 30 mg L -1 of dye, within the range of typical concentration in textile waste waters, were treated under the mild operating conditions of natural pH of 6.75 and temperature of 25 °C. Investigations on the active species showed that hydroxyl radicals play the major role in the process, providing a perfect degradation...
Experimental Studies on Biodiesel Production Using Waste Frying Oil in a Hetergogeneous Catalytic Reaction
, M.Sc. Thesis Sharif University of Technology ; Kariminia, Hamid Reza (Supervisor) ; Shaygan Salek, Jalaloddin (Supervisor) ; Pazouki, Mohammad (Co-Advisor)
Abstract
Biodiesel can be a good alternative for fossil diesel since it isrenewable, biodegradable and non-toxic. Also, in comparison with fossil fuels, it emits less air pollutants and greenhouse gases.Findacost effective and environmentally friendly wayforcontinuousproductionofbiodieselcanaddressmany of our environmental concerns. In this study, we applied heterogeneous alkali-catalyzed transesterification as method and used waste frying oil as a low cost feedstock for biodiesel production. The project was performed in two phases. First, experiments were conducted in astirred reactor to finda suitable catalyst which was strontium carbonate calcinated for 3:24 hours in 975̊C.
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Adsorption Process Modeling by Rigorous Solution Method, on the Packed Bed Filled Zeolite
, M.Sc. Thesis Sharif University of Technology ; Rashtchian, Davood (Supervisor) ; Taghikhani, Vahid (Supervisor) ; Farhadi, Fatolla (Supervisor)
Abstract
The appearance of water in pipe lines of the natural gas transportation would cause several problems. In this regard, disparate methods have been developed to produce and refine of the natural gas, and one of the most common method is adsorption process. In this study, modeling and simulation of the adsorption process in the packed bed of zeolite 4A has been done. This research includes four steps, first, adsorption process and all types of adsorbent were investigated. Second, using rigorous solution method, equations of mass and energy balance derived. Third, using the collocation method and MATLAB programing, system equations of mass and energy was solved. Finally, accuracy of simulation...
Bio-oxidation of ferrous ions by Acidithioobacillus ferrooxidans in amonolithic bioreactor
, Article Journal of Chemical Technology and Biotechnology ; Volume 84, Issue 4 , 2009 , Pages 504-510 ; 02682575 (ISSN) ; Alemzadeh, I ; Vossoughi, M ; Sharif University of Technology
2009
Abstract
Background: The bio-oxidation of ferrous iron is a potential industrial process in the regeneration of ferric iron and the removal of H2S in combustible gases. Bio-oxidation of ferrous iron may be an alternative method of producing ferric sulfate, which is a reagent used for removal of H2S from biogas, tail gas and in the pulp and paper industry. For practical use of this process, this study evaluated the optimal pH and initial ferric concentration. pH control looks like a key factor as it acts both on growth rate and on solubility ofmaterials in the system. Results: Process variables such as pH and amount of initial ferrous ions on oxidation by A. ferrooxidans and the effects of process...
Immobilization of Acidithiobacillus ferrooxidans on monolithic packing for biooxidation of ferrous iron
, Article Iranian Journal of Biotechnology ; Volume 6, Issue 3 , 2008 , Pages 137-143 ; 17283043 (ISSN) ; Alemzadeh, I ; Vossoughi, M ; Sharif University of Technology
2008
Abstract
The oxidation of ferrous iron (Fe2+) in solution using Acidithiobacillus ferrooxidans has industrial applications exclusively in the regeneration of ferric iron (Fe3+) as an oxidizing agent for the removal of hydrogen sulfide from waste gases, desulfurization of coal, leaching of non-ferrous metallic sulfides and treatment of acid mine drainage. The aim of this investigation was to increase the bio-oxidation rate of ferrous sulfate by using immobilized cells. Rate of Fe2+ oxidation was determined in a packed-bed bioreactor configuration with monolithic particles being used as support material. Biooxidation of ferrous iron by immobilized cells was investigated in repeated batch culture and...
Experimental and modeling study of catalytic reaction of glucose isomerization: Kinetics and packed-bed dynamic modeling
, Article AIChE Journal ; Volume 54, Issue 5 , 2008 , Pages 1333-1343 ; 00011541 (ISSN) ; Safari, I ; Karima, M. M ; Sharif University of Technology
2008
Abstract
The kinetics and equilibrium of isomerization reaction of D-glucose to D-fructose have been investigated using a commercial immobilized glucose isomer ase (IGI), Sweetzyme type IT®, in a batch stirred-tank reactor. The batch experimental data were used to model the reaction kinetics using the well-known Michaelis-Menten rate expression. The kinetic model was utilized in a dynamic-mathematical model for a packed-bed reactor to predict the concentration profiles of D-glucose and D-fructose within the reactor. The experimental results for the fractional conversion of D-glucose in the packed-bed reactor of IGI catalyst indicated that the model prediction of the transient and steady-state...
Optimization of ferrous biooxidation rate in a packed bed bioreactor using Taguchi approach
, Article Chemical Engineering and Processing: Process Intensification ; Volume 46, Issue 10 , 2007 , Pages 935-940 ; 02552701 (ISSN) ; Yaghmaei, S ; Jafari, A ; Vossoughi, M ; Ghobadi, Z ; Sharif University of Technology
2007
Abstract
The biological oxidation of ferrous ion by iron-oxidizing bacteria is potentially a useful industrial process for removal of H2S from industrial gases, desulphurization of coal, removal of sulfur dioxide from flue gas, treatment of acid mine drainage and regeneration of an oxidant agent in hydrometallurgical leaching operations. The main purpose of this study was to find optimum values of the process parameters on the ferrous biooxidation rate by immobilization of a native Sulfobacillus species on the surface of low density polyethylene (LDPE) particles in a packed-bed bioreactor using Taguchi method. Five control factors, including temperature, initial pH of feed solution, dilution rate,...
Modeling of multiple noncatalytic gas-solid reactions in a moving bed of porous pellets based on finite volume method
, Article Heat and Mass Transfer/Waerme- und Stoffuebertragung ; Volume 43, Issue 9 , 2007 , Pages 881-894 ; 09477411 (ISSN) ; Saboohi, Y ; Sharif University of Technology
2007
Abstract
A mathematical model is presented to simulate the multiple heterogeneous reactions with complex set of physicochemical and thermal phenomena in a moving bed of porous pellets. This model is based on both heat and mass transfer phenomena of gaseous species in a porous medium including chemical reactions at interfaces whose areas vary during the conversion. This model accounts for both the exothermic and endothermic reactions which can be equimolar or nonequimolar. Furthermore it considers simultaneously the reactions in the nonisothermal transient condition. A powerful technique based upon finite volume fully implicit approach has been implemented to solve the complicated governing equations...
Influence of process variables on biooxidation of ferrous sulfate by an indigenous Acidithiobacillus ferrooxidans. Part II: Bioreactor experiments
, Article Fuel ; Volume 86, Issue 7-8 , 2007 , Pages 993-999 ; 00162361 (ISSN) ; Yaghmaei, S ; Jafari, A ; Sharif University of Technology
2007
Abstract
The oxidation of ferrous iron in solution using Acidithiobacillus ferrooxidans has industrial applications in the regeneration of ferric iron as an oxidant agent for the removal of hydrogen sulfide from waste gases, desulphurization of coal, leaching of non-ferrous metallic sulfides and treatment of acid mine drainage. The aim of this attempt was to increase the biooxidation rate of ferrous sulfate by using immobilized cells. Rate of ferrous iron oxidation was determined in a packed-bed reactor configuration with low density polyethylene (LDPE) particles as support material in order to find the most practical system for scale-up. The present work studies the influence of basic parameters on...
Simulation of fluid flow through a granular bed
, Article 8th Biennial ASME Conference on Engineering Systems Design and Analysis, ESDA2006, Torino, 4 July 2006 through 7 July 2006 ; Volume 2006 , 2006 ; 0791837793 (ISBN); 9780791837795 (ISBN) ; Mousavi, S. M ; Sharif University of Technology
American Society of Mechanical Engineers
2006
Abstract
Numerical study of flow through random packing of non-overlapping spheres in a cylindrical geometry is investigated. Dimensionless pressure drop has been studied for a fluid through the porous media at moderate Reynolds numbers (based on pore permeability and interstitial fluid velocity), and numerical solution of Navier-Stokes equations in three dimensional porous packed bed illustrated in excellent agreement with those reported by Macdonald [1979] in the range of Reynolds number studied. The results compare to the previous work (Soleymani et al., 2002) show more accurate conclusion because the problem of channeling in a duct geometry. By injection of solute into the system, the...
Two-dimensional axisymmetric modelingof combustion in an iron ore sintering bed
, Article Special Topics and Reviews in Porous Media ; Volume 4, Issue 4 , 2013 , Pages 299-313 ; 21514798 (ISSN) ; Emami, M. D ; Panjehpour, M ; Sohrabi, S ; Sharif University of Technology
2013
Abstract
A twodimensional model, based on conservation of mass, momentum and energy equations, is represented in this paper in which the coke combustion process, for iron ore sintering in a packed bed, is simulated numerically. The aforementioned packed bed consists of iron ore, coke, limestone and moisture. The main objective of iron ore sintering is producing resistant agglomerates which can be used in blast furnaces. For this purpose, the sinter mixture is partially melted in high temperature and finally molten is allowed to cool. The molten production and subsequently, the solidification process are totally dependent on composition and components of mixture. Changes in bed porosity, caused by...
Reactive absorption in packed bed columns in the presence of magnetic nanoparticles and magnetic field: Modeling and simulation
, Article Journal of Industrial and Engineering Chemistry ; Volume 45 , 2017 , Pages 131-144 ; 1226086X (ISSN) ; Molaei Dehkordi, A ; Sharif University of Technology
Korean Society of Industrial Engineering Chemistry
2017
Abstract
In this article, the influences of ferrofluid and magnetic field on the reactive absorption in packed-bed contactors have been investigated. Because of importance of carbon dioxide emission as a global concern, absorption of carbon dioxide was chosen to investigate these effects. In this regard, multitube approach was applied to model the contactor. The simulation results were validated against experimental data reported in the literature in the absence of nanoparticles and magnetic field and good agreement was obtained. Moreover, influences of various operating conditions on the contactor performance were investigated. It was found that for 3.4 vol.% of magnetic nanoparticles (MNPs), the...
Sulphate reduction in a three-stage packed-bed anaerobic bioreactor
, Article World Environmental and Water Resources Congress 2008: Ahupua'a, Honolulu, HI, 12 May 2008 through 16 May 2008 ; Volume 316 , 2008 ; 9780784409763 (ISBN) ; Poorhashem, Q ; Environmental and Water Resources Institute of ASCE ; Sharif University of Technology
2008
Abstract
In this paper the effect of the sulphate concentration on the performance of a three-stage anaerobic baffled packed-bed reactor (ABPR) was investigated. Synthetic wastewater (3000 mg COD/l) was used as the sole organic substrate. The 30 liters fixed-bed bioreactor filled with plastic packing and divided in three equal sections was used as the mABPR reactor. The unit was run at a hydraulic retention time (HRT) of 1 day and at temperature of 25° C. The results of this study showed that when COD/SO42- ratios were changed from 30 to 3 with increasing sulphate concentration from 100 to 1000 mg/l, COD removal slightly was decreased. Maximum COD and sulphate removal were 91 and 96%, respectively,...
Modelling of one-dimensional heterogeneous catalytic steam methane reforming over various catalysts in an adiabatic packed bed reactor
, Article International Journal of Hydrogen Energy ; Volume 46, Issue 7 , 2021 , Pages 5112-5130 ; 03603199 (ISSN) ; Abbas, S. Z ; Ramirez Solis, S ; Dupont, V ; Mahmud, T ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Kinetic data relevant to steam methane reforming (SMR) are often applied to catalysts and conditions for which they have not been derived. In this work, kinetic rates for the two SMR and water gas shift reactions were derived for 12 commonly used reforming catalysts based on conversion data obtained from the literature. Subsequently, these rates were tested in dynamic operation, steady-state, and equilibrium using a 1-D reactor model developed in-house with gPROMS model builder. Modelling outputs were further validated independently at equilibrium using the software chemical equilibrium with applications (CEA), and the literature. The effect of variables such as temperature, pressure, steam...