Spatiotemporal patterns in an isothermal heterogeneous model of a fixed‐bed reactor

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.

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Modeling and Optimization of MeOH to DME in Isothermal Fixed-bed Reactor

International Journal of Chemical Reactor Engineering ◽

10.2202/1542-6580.2063 ◽

2010 ◽

Vol 8 (1) ◽

Cited By ~ 8

Author(s):

Mohammad Farsi ◽

Abdolhossein Jahanmiri ◽

Reza Eslamloueyan

Keyword(s):

Fixed Bed ◽

Methanol Conversion ◽

Fixed Bed Reactor ◽

Methanol Dehydration ◽

Algebraic Equations ◽

Optimal Temperature ◽

Heterogeneous Model ◽

One Dimensional ◽

Shell And Tube ◽

Green Fuel

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.

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Modeling and Simulation of a Packed-bed Reactor for Carrying out the Water-Gas Shift Reaction

International Journal of Chemical Reactor Engineering ◽

10.1515/1542-6580.3105 ◽

2012 ◽

Vol 10 (1) ◽

Cited By ~ 2

Author(s):

Yaidelin A. Manrique ◽

Carlos V. Miguel ◽

Diogo Mendes ◽

Adelio Mendes ◽

Luis M. Madeira

Keyword(s):

Fixed Bed ◽

Packed Bed ◽

Packed Bed Reactor ◽

Fixed Bed Reactor ◽

Water Gas Shift ◽

Small Scale ◽

Heterogeneous Model ◽

Co Conversion ◽

Reactor Operating ◽

Water Gas

Abstract In this work the water-gas shift (WGS) process was addressed, with particular emphasis in the development of phenomenological models that can reproduce experimental results in a WGS reactor operating at low temperatures. It was simulated the conversion obtained in a fixed-bed reactor (PBR) packed with a Cu-based catalyst making use of a composed kinetic equation in which the Langmuir-Hinshelwood rate model was used for the lowest temperature range (up to 215 ºC), while for temperatures in the range 215 – 300 ºC a redox model was employed. Several packed-bed reactor models were then proposed, all of them without any fitting parameters. After comparing the simulations against experimental CO conversion data for different temperatures and space time values, it was concluded that the heterogeneous model comprising axial dispersion and mass transfer resistances shows the best fitting. This model revealed also good adherence to other experiments employing different feed compositions (CO and H2O contents); it predicts also the overall trend of increasing CO conversion with the total pressure. This modeling work is particularly important for small scale applications related with hydrogen production/purification for fuel cells.

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

10.32920/ryerson.14639241.v1 ◽

2021 ◽

Author(s):

Ali Elkamel ◽

Gholam Reza Zahedi ◽

Chris Marton ◽

Ali Lohi

Keyword(s):

Fixed Bed ◽

Fixed Bed Reactor ◽

Industrial Plant ◽

Production Network ◽

Heterogeneous Model ◽

Methanol Production ◽

In Series ◽

Maximum Production Rate ◽

Production Period ◽

Reactor Network

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.

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

10.32920/ryerson.14639241 ◽

2021 ◽

Author(s):

Ali Elkamel ◽

Gholam Reza Zahedi ◽

Chris Marton ◽

Ali Lohi

Keyword(s):

Fixed Bed ◽

Fixed Bed Reactor ◽

Industrial Plant ◽

Production Network ◽

Heterogeneous Model ◽

Methanol Production ◽

In Series ◽

Maximum Production Rate ◽

Production Period ◽

Reactor Network

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.

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