scholarly journals Optimal Fixed Bed Reactor Network Configuration for the Efficient Recycling of CO2 into Methanol

Author(s):  
Ali Elkamel ◽  
Gholam Reza Zahedi ◽  
Chris Marton ◽  
Ali Lohi

An optimal design strategy of a network of fixed bed reactors for Methanol Production (MP) is proposed in this study. Both methanol production and profit spanning a production period of eight years have been set as objective functions to find the optimal production network. The conservation of mass and energy laws on a heterogeneous model of a single industrial methanol reactor was first developed. The model was solved numerically and was validated with industrial plant data. Different reactor network arrangements were then simulated in order to find an optimal superstructure. It was found that a structure of four reactors (two in series in parallel with another two in series) provide maximum production rate. The application of the more realistic objective function of profit showed that a configuration of two parallel reactors is the best configuration. This optimal structure produces 92 tons/day more methanol than a single reactor.

2021 ◽  
Author(s):  
Ali Elkamel ◽  
Gholam Reza Zahedi ◽  
Chris Marton ◽  
Ali Lohi

An optimal design strategy of a network of fixed bed reactors for Methanol Production (MP) is proposed in this study. Both methanol production and profit spanning a production period of eight years have been set as objective functions to find the optimal production network. The conservation of mass and energy laws on a heterogeneous model of a single industrial methanol reactor was first developed. The model was solved numerically and was validated with industrial plant data. Different reactor network arrangements were then simulated in order to find an optimal superstructure. It was found that a structure of four reactors (two in series in parallel with another two in series) provide maximum production rate. The application of the more realistic objective function of profit showed that a configuration of two parallel reactors is the best configuration. This optimal structure produces 92 tons/day more methanol than a single reactor.


Author(s):  
Pablo Giunta ◽  
Norma Amadeo ◽  
Miguel Laborde

The aim of this work is to design an ethanol steam reformer to produce a hydrogen stream capable of feeding a 60 kW PEM fuel cell applying the plug flow model, considering the presence of the catalyst bed (heterogeneous model). The Dusty-Gas Model is employed for the catalyst, since it better predicts the fluxes of a multicomponent mixture. Moreover, this model has shown to be computationally more robust than the Fickian Model. A power law-type kinetics was used. Results showed that it is possible to carry out the ethanol steam reforming in a compact device (1.66 x 10 -5 to 5.27 x 10 -5 m3). It was also observed that this process is determined by heat transfer.


REAKTOR ◽  
2019 ◽  
Vol 19 (3) ◽  
pp. 131-135
Author(s):  
Fadilla Noor Rahma

CO2 capture and utilization (CCU) has been widely considered as a potential solution to overcome global warming. Conversion of CO2 into methanol is an interesting option to transform waste into value-added chemical while also reducing greenhouse gases emissions in the atmosphere. In this paper, utilization of CO2 into methanol was simulated using Aspen Plus software. The reaction between CO2 and H2 to produce methanol and water was carried out in a simulated fixed-bed reactor with Cu/ZnO/Al2O3 commercial catalyst, following LHHW (Langmuir – Hinshelwood – Hougen – Watson) kinetic model. Isothermal and adiabatic reactor configurations were compared under similar feed conditions and the concentration profile along the reactor was observed. The result showed that isothermal configuration converted 3.23% more CO2 and provided 16.34% higher methanol yield compared to the adiabatic reactor. Feed inlet temperature variation was applied and the effect to methanol production on both configurations was studied. The highest methanol yield for adiabatic and isothermal reactor was obtained at 200 oC and 240 oC respectively.


2020 ◽  
Vol 400 ◽  
pp. 159-169
Author(s):  
Sara F.H. Tasfy ◽  
Noor Asmawati Mohd Zabidi ◽  
Maizatul Shima Shaharun ◽  
Duvvria Subbarao

Bimetallic Cu-ZnO-based catalyst were systematically prepared via impregnation technique under controlled synthesis conditions of active metal loading, ratio of active metal Cu:Zn and synthesis pH. The effect of the synthesis condition on the performance of the Cu-ZnO supported catalysts with respect to the hydrogenation of CO2 to methanol in micro-activity fixed-bed reactor at 250°C, 2.25 MPa, and 75% H2/25%CO2 ratio. The synthesized catalysts were characterized by transmission electron microscopy (TEM) and temperature programmed desorption, reduction, oxidation and pulse chemisorption (TPDRO) and the surface area determination was also performed. The results demonstrate that the catalytic structure, activity, and methanol selectivity was strongly affected by the synthesis parameters. Increasing of synthesis pH from 1 to 7 shows better metal particles distribution, Cu desperation of 29%, higher BET surface area as well as Cu surface area, while further increasing on pH revealed on particles agglomeration and weak metal-support interaction. In addition, increasing of the active metal loading from 5 to 15 % resulted in dramatic increase in the conversion of CO2 and methanol production while further increase caused lower catalytic performance. Moreover, catalyst with total loading of 15%, Cu:Zn ratio of 70:30 synthesized at pH of 7 exhibit higher catalytic activity of 14%, methanol selectivity of 92%, and TOF of 1.24×103 s-1 compared with other catalyst prepared under various conditions


Author(s):  
Mohammad Farsi ◽  
Abdolhossein Jahanmiri ◽  
Reza Eslamloueyan

Dimethyl ether (DME) is a green fuel that commercially produced in an adiabatic fixed bed reactor by methanol dehydration. In the present work, a shell and tube fixed bed reactor is modeled and optimized for DME production. The reactor is modeled based on mass and energy conservation equations as well as auxiliary equations. In order to estimate the DME production and temperature profile along the reactor, a one dimensional heterogeneous model consist of a set of nonlinear differential and algebraic equations has been solved numerically. Also, The DME production in the isothermal reactor is maximized by adjusting the optimal temperature distribution along the reactor using genetic algorithm. Then, the performance of the proposed isothermal reactor is compared with industrial adiabatic fixed bed reactor. Results showed the higher DME production rate and methanol conversion in the optimized reactor.


2016 ◽  
Vol 188 ◽  
pp. 545-563 ◽  
Author(s):  
N. Utsis ◽  
R. Vidruk-Nehemya ◽  
M. V. Landau ◽  
M. Herskowitz

Seven solid mono-, bi- and tri-metallic oxide matrices where Fe(2+,3+) ions are distributed in different chemical/spatial environments were synthesized and characterized by XRD, N2-adsorption and EDAX methods. After basification with potassium, all matrices were activated by carburization or reduction–carburization under conditions selected based on the TPC/TPR spectra, tailoring the carburization extent of iron. The performances of the activated Fe-based catalysts with respect to CO2 conversion and C5+ selectivity were measured in a fixed-bed reactor under standard conditions in transient and continuous operation modes in units containing one or three reactors in series with water separations between the reactors. The catalysts were characterized by XRD, N2-adsorption, HRTEM-EELS and XPS before and after steady-state operation in the reactors. It was found that the rate of CO2 conversion is not limited by thermodynamic equilibrium but is strongly restricted by water inhibition and it depends on the nature of the Fe-oxide precursor. The ratio between the FTS and RWGS rates, which determines the C5+ hydrocarbons productivity, is strongly affected by the nature of the Fe-oxide matrix. The catalysts derived from the Fe–Al–O spinel and Fe–Ba–hexaaluminate precursors displayed the best balance of the two functions RFTS/RRWGS = 0.77–0.78. They were followed by magnetite, CuFe–delafossite, K–ferrite, Fe–La–hexaaluminate and LaFe–perovskite with a gradual lowering of RFTS/RRWGS from 0.60 to 0.15 and a gradual decrease in the C5+ productivity. The active sites that enhance the RWGS reaction are located on the surface of the Fe-oxide phases, while the FTS and methanation reactions occur on the surface of the Fe-carbide phases.


Sign in / Sign up

Export Citation Format

Share Document