Investigation of a Steam Reforming System of Methane Integrated With a Combustion Burner

2008 ◽  
Author(s):  
Joonguen Park ◽  
Shinku Lee ◽  
Joongmyeon Bae ◽  
Myungjun Kim
Keyword(s):  
Steam Reforming ◽  
Homogeneous Model ◽  
Operating Parameter ◽  
Feed Ratio ◽  
Steam Reformer ◽  
Combustion Gas ◽  
Transfer Rates ◽  
Fuel Feed ◽  
Combustion Gases ◽  
Reactor Temperature

The objective of this study is to analyze the steam reforming system using numerical method. The system consists of a cylindrical-type steam reformer and a combustion burner. Heat is supplied to the endothermic steam reformer by the combustion gases which flow around the reformer. Eddy Break-Up (EBU) model is incorporated for the combustion reaction, and pseudo-homogeneous model is used for the steam reforming reaction. The temperature at the reformer center and the concentration of species at the outlet are compared with the measured data for code validation. The correlation between the performances and the shapes of the system has been studied by using two different configurations. One has the flame guide between the combustion burner and the steam reformer, and the other does not. The flame guide makes the flow of the combustion gas changed. The operating parameters are reactant flow rates which are supplied to the steam reformer and the combustion burner. Reactor temperature profiles, heat transfer rates, fuel conversion, and the hydrogen yields are calculated as the numerical results. Moreover, fuel feed ratio between the burner and the reformer is also manipulated as an operating parameter to discuss about efficiency.

Numerical Analysis of a Steam Reformer Coupled With a Combustion Burner

2010 ◽  
Vol 7 (6) ◽  
Author(s):  
Joonguen Park ◽  
Joongmyeon Bae ◽  
Shinku Lee ◽  
Myungjun Kim
Keyword(s):  
Heat Transfer ◽  
Steam Reforming ◽  
Operating Parameter ◽  
Feed Ratio ◽  
Steam Reformer ◽  
Combustion Gas ◽  
Transfer Rates ◽  
Fuel Feed ◽  
Combustion Gases ◽  
Reactor Temperature

This study focuses on a numerical simulation of a steam reforming system. The steam reforming system consisted of a cylindrical steam reformer and a combustion burner. The heat was supplied to an endothermic steam reformer from combustion gases. The correlation between the performance and the shape of the system was studied using two different configurations. The first configuration utilized a flame guide between the combustion burner and the steam reformer, whereas the other did not. The flame guide changed the flow of the combustion gas, which affected the heat transfer rate from the burner to the reformer. Reactor temperature profiles, heat transfer rates, fuel conversions, and hydrogen yields were calculated. In addition, the fuel feed ratio between the burner and the steam reformer was manipulated as an operating parameter.

scholarly journals Steam reforming of ethanol for hydrogen production: influence of catalyst composition (Ni/Al2O3, Ni/Al2O3–CeO2, Ni/Al2O3–ZnO) and process conditions

2021 ◽  
Vol 132 (2) ◽  
pp. 907-919
Author(s):  
O. Shtyka ◽  
Z. Dimitrova ◽  
R. Ciesielski ◽  
A. Kedziora ◽  
G. Mitukiewicz ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Steam Reforming ◽  
Catalyst Stability ◽  
Feed Ratio ◽  
Ethanol Conversion ◽  
Process Conditions ◽  
Catalyst Activation ◽  
Catalyst Composition ◽  
Activity Measurements ◽  
Steam Reforming Of Ethanol

AbstractEthanol steam reforming was studied over Ni supported catalysts. The effects of support (Al2O3, Al2O3–ZnO, and Al2O3–CeO2), metal loading, catalyst activation method, and steam-to-ethanol molar feed ratio were investigated. The properties of catalysts were studied by N2 physisorption, TPD-CO2, X-ray diffraction, and temperature programmed reduction. After activity tests, the catalysts were analyzed by TOC analysis. The catalytic activity measurements showed that the addition either of ZnO SSor CeO2 to alumina enhances both ethanol conversion and promotes selectivity towards hydrogen formation. The same effects were observed for catalysts with higher metal loadings. High process temperature and high water-to-ethanol ratio were found to be beneficial for hydrogen production. An extended catalyst stability tests showed no loss of activity over 50 h on reaction stream. The TOC analysis of spent catalysts revealed only insignificant amounts of carbon deposit.

scholarly journals Simulation of Steam Reforming Tube with Shaped Particles

2016 ◽  
Vol 7 (1) ◽  
pp. 57 ◽  
Author(s):  
A.P. Kagyrmanova ◽  
N.V. Vernikovskaya ◽  
I.A. Zolotarsky ◽  
E.I. Smirnov ◽  
V.A. Kuzmin
Keyword(s):  
Steam Reforming ◽  
Radial Direction ◽  
Tube Wall ◽  
Homogeneous Model ◽  
Packed Bed ◽  
Intraparticle Diffusion ◽  
Simulated Performance ◽  
Reaction Stoichiometry ◽  
Gas Volume ◽  
Convective Mass Flux

<p>Shaped catalysts are widely used in steam reforming. A comprehensive mathematical model able to predict and compare performance of different shaped catalysts is developed. The two-dimensional pseudo homogeneous model accounts for heat transfer between the tube wall and catalyst bed, conductivity and diffusivity in the radial direction in the packed bed and intraparticle diffusion. Gas volume changing caused by reaction stoichiometry results in a radial convective mass flux. A verification of the model and simulated performance of different shaped catalysts in steam reforming of natural gas are presented.</p>

Combustion Gas Properties: Part II—Prediction of Partial Pressures of CO2 and H2O in Combustion Gases of Aviation and Diesel Fuels

1986 ◽  
Vol 108 (3) ◽  
pp. 455-459 ◽  
Author(s):  
O¨. L. Gu¨lder
Keyword(s):  
Chemical Equilibrium ◽  
Absolute Error ◽  
Functional Expression ◽  
Atomic Ratio ◽  
Aviation Fuel ◽  
Combustion Gas ◽  
Combustion Gases ◽  
Diesel Fuels ◽  
Partial Pressures ◽  
Detailed Chemical

Empirical formulae are presented by means of which the partial pressures of CO2 and H2O in the combustion gases of aviation fuel-air and diesel fuel-air systems can be calculated as functions of pressure, temperature, equivalence ratio, and hydrogen-to-carbon atomic ratio of the fuel. The formulae have been developed by fitting the data from a detailed chemical equilibrium code to a functional expression. Comparisons of the results from the proposed formulae with the results obtained from a chemical equilibrium code have shown that the mean absolute error in predicted partial pressures is around 0.8 percent. These formulae provide a very fast and easy means of predicting partial pressures of CO2 and H2O as compared to equilibrium calculations, and they are also applicable to gasolines, residual fuels, and pure alkanes and aromatics as well as aviation and diesel fuels.

Temperature and Concentration Simulations in the Methanol Steam Reformer

2008 ◽  
Author(s):  
Yen-Cho Chen ◽  
Rei-Yu Chein ◽  
Li-Chun Chen
Keyword(s):  
Steam Reforming ◽  
Heat Supply ◽  
Methanol Conversion ◽  
Methanol Steam Reforming ◽  
Gas Temperature ◽  
Steam Reformer ◽  
Portable Power ◽  
Supply Channel ◽  
Hydrogen Supply ◽  
Portable Power Applications

The methanol steam reforming plays an important role for hydrogen supply to the proton membrane exchange fuel cell in the portable power applications. The catalyst coating on the walls of channels is often used in the fabrication of the reactors in the reformer to minimize the pressure loss. In this study, the temperature and concentration fields in the reactors for the methanol steam reforming were investigated numerically. The methanol conversion is usually used to evaluate the performance of the reformer. The effects of the inlet gas temperature in the heat supply channel and inlet velocity in the reforming channel on the performance of the methanol steam reforming are presented.

Preparation of Cu/ZnO for Fabrication of a Micro Methanol Reformer

2007 ◽  
Vol 119 ◽  
pp. 235-238
Author(s):  
Hong Seock Cha ◽  
Tae Gyu Kim ◽  
Se Jin Kwon
Keyword(s):  
Steam Reforming ◽  
Methanol Conversion ◽  
Catalyst Loading ◽  
Fabrication Method ◽  
Micro Structure ◽  
Micro Fabrication ◽  
Steam Reformer ◽  
Steam Reforming Of Methanol ◽  
Strong Adhesion ◽  
Micro Reactor

Three synthesis procedures of Cu/ZnO catalyst for steam reforming of methanol were tested for loading in a micro reactor. The best procedure that resulted in the strong adhesion to the wafer was determined out of the tested procedures. The molecular structure of the synthesized catalyst was examined by XRD and its performance in methanol conversion was measured. A micro fabrication method that incorporates the catalyst loading and micro structure processing was developed. A MEMS methanol steam reformer was built by this process and the completed device resulted in methanol conversion of 93%.

Enhancing the Steam-Reforming Process With Acoustics: A Theoretical Investigation of Potential Benefits for Application in Fuel Cell Vehicles

2000 ◽  
Author(s):  
Paul A. Erickson ◽  
Vernon P. Roan
Keyword(s):  
Fuel Cell ◽  
Steam Reforming ◽  
Acoustic Waves ◽  
Space Velocity ◽  
Hydrocarbon Fuel ◽  
Acoustic Fields ◽  
Fuel Cell Vehicles ◽  
Transfer Rates ◽  
Start Up ◽  
Potential Benefits

Abstract This paper provides a theoretical basis for the investigation of using acoustic waves as a means of enhancing performance in conjunction with the hydrocarbon fuel steam-reforming process for application in fuel cell vehicles. In order to minimize liabilities associated with steam-reforming, a novel reforming enhancement is being investigated. A reformation process that utilizes acoustic fields in critical fluid paths is introduced. Potential benefits of using acoustic fields in the reformation process are decreased effective space velocity, an increase of convective heat transfer rates, and increased specie mixing that would help produce an increase in capacity and overall reaction rate for a given reformer volume. The proposed acoustic enhancement should result in some combination of quicker start up times, faster dynamic response, smaller size and lower weight.

Multiobjective Dynamic Optimization of an Industrial Steam Reformer with Genetic Algorithms

2007 ◽  
Vol 5 (1) ◽  
Author(s):  
Ali Alizadeh ◽  
Navid Mostoufi ◽  
Farhang Jalali-Farahani
Keyword(s):  
Steady State ◽  
Dynamic Optimization ◽  
Synthesis Gas ◽  
Transition Period ◽  
Dynamic Condition ◽  
Homogeneous Model ◽  
Operating Conditions ◽  
Reactor Performance ◽  
Steady State Condition ◽  
Steam Reformer

An industrial steam reformer of a methanol plant was modeled at a dynamic condition in which a one dimensional homogeneous model was coupled with a verified kinetics from the literature. A close agreement was observed between the results of the model and industrial data from a real plant at steady state conditions. The open loop response of the system to switching between two operating conditions was investigated and shown that the produced synthesis gas during the transition period would be unsuitable for the downstream methanol converter. The genetic algorithm was then employed to perform a multi-objective dynamic optimization on the reactor performance in case of switching the feed and operating conditions. Maximization of methane conversion and minimization of a stoichiometric parameter, were considered as the two objectives' functions that were optimized for a fixed feed rate of methane to the existing unit. The results of the dynamic optimization for the specified reformer configuration were achieved after switching the operating condition. Results of the optimization showed that the produced synthesis gas would stay in its acceptable limits in terms of quality of the feed of the methanol converter and also, the final conversion of the reformer would be improved compared to the steady state condition. This procedure could be applied to the advanced process control of the methanol plant.

scholarly journals Influence of Steam Reforming Catalyst Geometry on the Performance of Tubular Reformer – Simulation Calculations

2015 ◽  
Vol 36 (2) ◽  
pp. 239-250 ◽  
Author(s):  
Ewelina Franczyk ◽  
Andrzej Gołębiowski ◽  
Tadeusz Borowiecki ◽  
Paweł Kowalik ◽  
Waldemar Wróbel
Keyword(s):  
Natural Gas ◽  
Steam Reforming ◽  
Flow Resistance ◽  
Gas Flow ◽  
Process Analysis ◽  
Homogeneous Model ◽  
Tubular Reactor ◽  
Tube Length ◽  
Cylinder Surface ◽  
Reforming Catalyst

Abstract A proper selection of steam reforming catalyst geometry has a direct effect on the efficiency and economy of hydrogen production from natural gas and is a very important technological and engineering issue in terms of process optimisation. This paper determines the influence of widely used seven-hole grain diameter (ranging from 11 to 21 mm), h/d (height/diameter) ratio of catalyst grain and Sh/St (hole surface/total cylinder surface in cross-section) ratio (ranging from 0.13 to 0.37) on the gas load of catalyst bed, gas flow resistance, maximum wall temperature and the risk of catalyst coking. Calculations were based on the one-dimensional pseudo-homogeneous model of a steam reforming tubular reactor, with catalyst parameters derived from our investigations. The process analysis shows that it is advantageous, along the whole reformer tube length, to apply catalyst forms of h/d = 1 ratio, relatively large dimensions, possibly high bed porosity and Sh/St ≈ 0.30-0.37 ratio. It enables a considerable process intensification and the processing of more natural gas at the same flow resistance, despite lower bed activity, without catalyst coking risk. Alternatively, plant pressure drop can be reduced maintaining the same gas load, which translates directly into diminishing the operating costs as a result of lowering power consumption for gas compression.

A Novel Wild-Land Fire-Fighting Foam for Minimizing the Phytotoxicity of Wood Burning-Derived Smoke Tested in Living Plant Cells

2014 ◽  
Vol 875-877 ◽  
pp. 725-733
Author(s):  
Atsuko Noriyasu ◽  
Kohei Otsuka ◽  
Yuki Ishizaki ◽  
Yutaka Tanaike ◽  
Ken Matsuyama ◽  
...  
Keyword(s):  
Japanese Cedar ◽  
Fire Fighting ◽  
Western Hemlock ◽  
Japanese Cypress ◽  
Living Plant ◽  
Combustion Gas ◽  
Combustion Gases ◽  
Ft Ir ◽  
The Impact ◽  
Major Hydrocarbon

Impact of wild-land fires to the ecosystem is highly complex. Damages to the ecosystem can be attributed not only to the direct impact of fire and release of toxic post-combustion gasses but also to the spraying of fire-fighting chemicals. Fire-fighting foam (FFF) agents are frequently applied for controls in wild-land fires including forest fire. However, effects of FFFs on the composition of the post-combustion gasses and the phytotoxicity of smoke derived from burning woods have not been determined to date. In the present study, with Fourier transform infrared spectroscopy (FT-IR), we have analyzed the chemical composition of the gasses derived from wood slices exposed to two distinct manners of combustion, namely, smoldering (gradual combustion without flame) and rapid burning (combustion with flame). Tested samples include slices of Japanese cedar, Japanese cypress, and Western hemlock. The amount of hydrocarbons, detected in the post-combustion gas such as methane, ethane, ethylene, propane, hexane, formaldehyde, acrolein and phenol, were higher in the gasses from smoldered samples. The major hydrocarbon found in the post-combustion gases processed in the presence of pilot flame was methane. Other hydrocarbons were hardly detectable. Addition of FFFs, namely, a soap-based FFF (designated as MK-08) and a detergent co cocktail-based FFF (Phos-chek) onto wooden slices resulted in slight increase in other hydrocarbons in the gasses derived from flame-driven combustion of wood slices. Interestingly, addition of Phos-chek drastically elevated the phytotoxicity of post-combustion gas derived from Western hemlock slices heated in the presence of pilot flame when assessed using the suspension cultured tobacco cells. In contrast, the soap-based FFF tested here did not alter the phytotoxicity of the post-combustion gasses, suggesting that soap-based FFF might minimize the impact of the fire-fighting activity to the living plants consisting the ecosystem in the forests and wild-land.

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