scholarly journals Solution and Parameter Identification of a Fixed-Bed Reactor Model for Catalytic CO2 Methanation Using Physics-Informed Neural Networks

Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1304
Author(s):  
Son Ich Ngo ◽  
Young-Il Lim
Keyword(s):  
Neural Networks ◽  
Reaction Kinetics ◽  
Flow Reactor ◽  
Plug Flow ◽  
Fixed Bed ◽  
Effectiveness Factor ◽  
Fixed Bed Reactor ◽  
Reactor Model ◽  
Co2 Methanation ◽  
Chemical Reaction Kinetics

In this study, we develop physics-informed neural networks (PINNs) to solve an isothermal fixed-bed (IFB) model for catalytic CO2 methanation. The PINN includes a feed-forward artificial neural network (FF-ANN) and physics-informed constraints, such as governing equations, boundary conditions, and reaction kinetics. The most effective PINN structure consists of 5–7 hidden layers, 256 neurons per layer, and a hyperbolic tangent (tanh) activation function. The forward PINN model solves the plug-flow reactor model of the IFB, whereas the inverse PINN model reveals an unknown effectiveness factor involved in the reaction kinetics. The forward PINN shows excellent extrapolation performance with an accuracy of 88.1% when concentrations outside the training domain are predicted using only one-sixth of the entire domain. The inverse PINN model identifies an unknown effectiveness factor with an error of 0.3%, even for a small number of observation datasets (e.g., 20 sets). These results suggest that forward and inverse PINNs can be used in the solution and system identification of fixed-bed models with chemical reaction kinetics.

scholarly journals Axial Dispersion Plug Flow Model for Methanol Dehydration Reactor

2021 ◽  
Author(s):  
Masoud Habibi Zare ◽  
Mohammad Davar Mahlouji
Keyword(s):  
Flow Model ◽  
Plug Flow ◽  
Fixed Bed ◽  
Effectiveness Factor ◽  
Fixed Bed Reactor ◽  
Pore Network Model ◽  
One Dimensional ◽  
Catalyst Pellet ◽  
Transfer Equations ◽  
Mass And Heat Transfer

Abstract One-dimensional heterogeneous dispersed plug flow (DPF) model is employed to model an adiabatic fixed-bed reactor for the catalytic dehydration of methanol to dimethyl ether (DME). The mass and heat transfer equations are numerically solved for the reactor. The concentration of the reactant and products and also the temperature varies along the reactor, therefore the effectiveness factor would also change in the reactor. We used the effectiveness factor that was simulated according to the diffusion and reaction in the catalyst pellet as a pore network model. The predicted distribution for the effectiveness factor was utilized for the reactor simulation. The simulation results were compared to the experimental data and a satisfactory agreement was confirmed.

Hydrogen Production from Ethanol Steam Reforming: Fixed Bed Reactor Design

2008 ◽  
Vol 6 (1) ◽  
Author(s):  
Pablo Giunta ◽  
Norma Amadeo ◽  
Miguel Laborde
Keyword(s):  
Steam Reforming ◽  
Flow Model ◽  
Multicomponent Mixture ◽  
Plug Flow ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Ethanol Steam Reforming ◽  
Heterogeneous Model ◽  
Ethanol Steam ◽  
Hydrogen Stream

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.

scholarly journals A Radial Flow Contactor for Ambient Air CO2 Capture

2020 ◽  
Vol 10 (3) ◽  
pp. 1080 ◽  
Author(s):  
Qian Yu ◽  
Wim Brilman
Keyword(s):  
Radial Flow ◽  
Flow Reactor ◽  
Operation Mode ◽  
Scale Up ◽  
Fixed Bed ◽  
Ambient Air ◽  
Fixed Bed Reactor ◽  
Batch Mode ◽  
Radial Flow Reactor ◽  
Continuous Application

Direct air capture (DAC) of CO2 can address CO2 emissions from distributed sources and produce CO2 from air virtually anywhere that it is needed. In this paper, the performance of a new radial flow reactor (RFR) for CO2 adsorption from ambient air is reported. The reactor uses a supported amine sorbent and is operated in a batch mode of operation or semi-continuously, respectively without or with sorbent circulation. The radial flow reactor, containing 2 kg of the adsorbent, is successfully scaled up from the experimental results obtained with a fixed bed reactor using only 1 g of the adsorbent. In the batch operation mode, the sorbent in the annular space of the RFR is regenerated in situ. With sorbent circulation, the RFR is loaded and unloaded batchwise and only used as an adsorber. A sorbent batch loaded with CO2 is transported to and regenerated in an external (fluid bed) regenerator. The RFR unit is characterized by a low contacting energy (0.7–1.5 GJ/ton-CO2) and a relatively short adsorption time (24–43 min) compared to other DAC processes using the same types of sorbents. The contactor concept is ready for further scale-up and continuous application.

scholarly journals Reversible Molten Catalytic Methane Cracking Applied to Commercial Solar-Thermal Receivers

Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6229
Author(s):  
Scott C. Rowe ◽  
Taylor A. Ariko ◽  
Kaylin M. Weiler ◽  
Jacob T. E. Spana ◽  
Alan W. Weimer
Keyword(s):  
Flow Reactor ◽  
Plug Flow ◽  
Hydrogen Fuel ◽  
Reactor Model ◽  
Solar Reactor ◽  
Greenhouse Emissions ◽  
Solar Reactors ◽  
And Performance ◽  
Methane Cracking ◽  
Technology Demonstrator

When driven by sunlight, molten catalytic methane cracking can produce clean hydrogen fuel from natural gas without greenhouse emissions. To design solar methane crackers, a canonical plug flow reactor model was developed that spanned industrially relevant temperatures and pressures (1150–1350 Kelvin and 2–200 atmospheres). This model was then validated against published methane cracking data and used to screen power tower and beam-down reactor designs based on “Solar Two,” a renewables technology demonstrator from the 1990s. Overall, catalytic molten methane cracking is likely feasible in commercial beam-down solar reactors, but not power towers. The best beam-down reactor design was 9% efficient in the capture of sunlight as fungible hydrogen fuel, which approaches photovoltaic efficiencies. Conversely, the best discovered tower methane cracker was only 1.7% efficient. Thus, a beam-down reactor is likely tractable for solar methane cracking, whereas power tower configurations appear infeasible. However, the best simulated commercial reactors were heat transfer limited, not reaction limited. Efficiencies could be higher if heat bottlenecks are removed from solar methane cracker designs. This work sets benchmark conditions and performance for future solar reactor improvement via design innovation and multiphysics simulation.

Optimal Design, Modeling and Simulation of an Ethanol Steam Reforming Reactor

2009 ◽  
Vol 7 (1) ◽  
Author(s):  
Luis E Arteaga ◽  
Luis M Peralta ◽  
Yannay Casas ◽  
Daikenel Castro
Keyword(s):  
Hydrogen Production ◽  
Modeling And Simulation ◽  
Design Patterns ◽  
Plug Flow ◽  
Fixed Bed ◽  
Cell System ◽  
Fixed Bed Reactor ◽  
Effect Of Temperature ◽  
Ethanol Conversion ◽  
Renewable Hydrogen

The optimum design, modeling and simulation of a fixed bed multi-tube reformer for the renewable hydrogen production are carried out in the present paper. The analogies between plug flow model and a fixed bed reactor are used as design patterns. The steam reformer is designed to produce enough hydrogen to feed a 200kW fuel cell system (>2.19molH/s) and considering 85% of fuel utilization in the cell electrodes. The reactor prototype is optimized and then analyzed using a multiphysics and axisymmetric model, implemented on FEMLABM(R) where the differential mass balance by convection-diffusion and the energy balance for convection-conduction are solved. The temperature profile is controlled to maximize hydrogen production. The catalyst bed internal profiles and the effect of temperature on ethanol conversion and carbon monoxide production are discussed as well.

scholarly journals Kinetic study of hydrolysis of ethyl acetate using caustic soda

2018 ◽  
Vol 7 (4) ◽  
pp. 1995 ◽  
Author(s):  
Mostafa Ghobashy ◽  
Mamdouh Gadallah ◽  
Tamer T.El-Idreesy ◽  
M. A.Sadek ◽  
Hany A.Elazab
Keyword(s):  
Caustic Soda ◽  
Ethyl Acetate ◽  
Flow Reactor ◽  
Design Method ◽  
Plug Flow ◽  
Tubular Reactor ◽  
Acid Base ◽  
Chemical Reaction Kinetics ◽  
Hydrolysis Of

We report here, the hydrolysis of ethyl acetate by using caustic soda which is followed by means of conductance measurements which is widely used in chemical industry. The main aim of this research is to study the parameters of production of ethyl acetate by chemical reaction kinetics using an anion ion-exchange acting as a catalyst and acid-base titrations. The reaction of ethyl acetate and sodium hydroxide (caustic-soda) is done in a plug-flow reactor (steady-state tubular reactor) under the effect of different parameters including temperature, concentration and flow-rate, which allows the determination of activation energy and rate constants, due to large number of experiments. Factorial design method is used for the calculations of the experiment. It was determined that the order of the reaction is a second-order reaction.  

Dynamic modeling and simulations of the behavior of a fixed-bed reactor-exchanger used for CO2 methanation

AIChE Journal ◽  
2017 ◽  
Vol 64 (2) ◽  
pp. 468-480 ◽  
Author(s):  
Rasmey Try ◽  
Alain Bengaouer ◽  
Pierre Baurens ◽  
Christian Jallut
Keyword(s):  
Dynamic Modeling ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Modeling And Simulations ◽  
Co2 Methanation

Numerical Simulation of NO Conversion in the N2/O2/NO by Dielectric Barrier Discharge

2011 ◽  
Vol 84-85 ◽  
pp. 426-430 ◽  
Author(s):  
Shui E Yin
Keyword(s):  
Flue Gas ◽  
Flow Reactor ◽  
Plug Flow ◽  
Plug Flow Reactor ◽  
Flow Reactors ◽  
Dielectric Barrier ◽  
Chemical Reaction Kinetics ◽  
General Relations ◽  
Energy And Momentum ◽  
Oxidation Reactor

The SO2 and NOX from the coal-fired power station are the main gaseous pollutants in the air, which causes acid rain and photochemical smog. However, the two consequences are recognized as one of the most serious global environment problems and must be controlled. The electro-catalysts oxidation technology is capable of oxidized the NO which the wet flue gas desulfurization processes (WFGD) could not achieve this goal, the products from the electro-catalysts oxidation reactor entering the WFGD and to removal then removed simultaneously. In this work, a plug-flow reactors model is presented that can describe the conversion of NOx by the discharge treatment of the exhaust gases at low temperatures and at atmospheric pressure in dielectric barrier reactors. The model takes into account the behavior of a plug-flow reactor are simplified versions of the general relations for conservation of mass, energy, and momentum. The variation regularity of the generated nitrogen oxides, the main free radicals, and the rate of NO produce (ROP) were be analog by take the plug flow reactor (PFR) model of chemical reaction kinetics in the mixed flue gas of N2/NO/O2 , and trying to seek out the dominant reactions relation to production and consumption NO in the non-equilibrium plasma system. The results indicated that the dominant free radical is the O3 in the mixed flue gas of N2/NO/O2.

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