Development of Methanol Steam Reformer for Chemical Recuperation

2000 ◽  
Vol 123 (4) ◽  
pp. 727-733 ◽  
Author(s):  
T. Nakagaki ◽  
T. Ogawa ◽  
K. Murata ◽  
Y. Nakata
Keyword(s):  
Rate Equation ◽  
Reaction Rate ◽  
Design Method ◽  
Gaseous Mixture ◽  
Packed Bed ◽  
Methanol Conversion ◽  
Methanol Steam Reforming ◽  
Steam Reformer ◽  
Product Gas ◽  
Reaction Rate Equation

The purpose of the present work is to establish the design method of methanol steam-reformer for application to chemical recuperation in a gas turbine system. The reaction rate of the methanol steam-reforming was measured with a small amount of catalyst using the gaseous mixture of methanol, water, hydrogen, and carbon dioxide as a simulated product gas. The reaction rate equation could be expressed by power law of methanol mole fraction and total pressure. The reaction and heat transfer in the catalyst-packed bed was analyzed numerically using the reaction rate equation. The analytical results of temperature distribution and conversion were compared with the experimental results using a reforming tube. These results agreed well except for the region of high methanol conversion.

The kinetics of the decarboxylation of β-resorcylic acid in catechol

1976 ◽  
Vol 29 (2) ◽  
pp. 443 ◽  
Author(s):  
MA Haleem ◽  
MA Hakeem
Keyword(s):  
Rate Equation ◽  
Kinetic Data ◽  
Reaction Rate ◽  
Complex Mechanism ◽  
First Order ◽  
Absolute Reaction Rate ◽  
First Time ◽  
Kinetics Of ◽  
Absolute Reaction ◽  
Reaction Rate Equation

Kinetic data are reported for the decarboxylation of β-resorcylic acid in resorcinol and catechol for the first time. The reaction is first order. The observation supports the view that the decomposition proceeds through an intermediate complex mechanism. The parameters of the absolute reaction rate equation are calculated.

Modeling of Gas Turbine Combustors—A Convenient Reaction Rate Equation

1972 ◽  
Vol 94 (3) ◽  
pp. 173-180 ◽  
Author(s):  
D. Kretschmer ◽  
J. Odgers
Keyword(s):  
Rate Equation ◽  
Reaction Rate ◽  
Reaction Order ◽  
Bimolecular Reaction ◽  
Rate Equations ◽  
Combustion System ◽  
Wide Range ◽  
Simple Mass ◽  
Rich Mixtures ◽  
Reaction Rate Equation

In order to model a practical combustion system successfully, it is necessary to develop one or more reaction rate equations which will describe performance over a wide range of conditions. The equations should be kept as simple as possible and commensurate with the accuracy needed. In this paper a bimolecular reaction is assumed, based upon a simple mass balance. Temperatures derived from the latter are related to measured practical ones such that, if required, an evaluation of the partly burned product composition can be made. A convenient reaction rate equation is given which describes a wide range of blow-out data for spherical reactors at weak mixture conditions. NVP2φ={1.29×1010(m+1)[5(1−yε)]φ[φ−yε]φe−C/(Ti+εΔT)}/{0.082062φyε[5(m+1)+φ+yε]2φ[Ti+εΔT]2φ−0.5} Analysis of the components used in the above equation (especially the variation of activation energy) clearly shows its empirical nature but does not detract from its engineering value. Rich mixtures are considered also, but lack of data precludes a reliable analysis. One of the major results obtained is the variation of the reaction order (n) with equivalence ratio (φ): weak mixtures, n = 2φ; rich mixtures, n = 2/φ. Some support for this variation has been noticed in published literature of other workers.

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.

scholarly journals Modeling and Design of a Multi-Tubular Packed-Bed Reactor for Methanol Steam Reforming over a Cu/ZnO/Al2O3 Catalyst

Energies ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 610 ◽  
Author(s):  
Jimin Zhu ◽  
Samuel Simon Araya ◽  
Xiaoti Cui ◽  
Simon Lennart Sahlin ◽  
Søren Knudsen Kær
Keyword(s):  
Steam Reforming ◽  
Packed Bed ◽  
Methanol Conversion ◽  
Operating Conditions ◽  
Packed Bed Reactor ◽  
Inlet Temperature ◽  
Methanol Steam Reforming ◽  
Shell Side ◽  
Co Concentration ◽  
The Impact

Methanol as a hydrogen carrier can be reformed with steam over Cu/ZnO/Al2O3 catalysts. In this paper a comprehensive pseudo-homogenous model of a multi-tubular packed-bed reformer has been developed to investigate the impact of operating conditions and geometric parameters on its performance. A kinetic Langmuir-Hinshelwood model of the methanol steam reforming process was proposed. In addition to the kinetic model, the pressure drop and the mass and heat transfer phenomena along the reactor were taken into account. This model was verified by a dynamic model in the platform of ASPEN. The diffusion effect inside catalyst particles was also estimated and accounted for by the effectiveness factor. The simulation results showed axial temperature profiles in both tube and shell side with different operating conditions. Moreover, the lower flow rate of liquid fuel and higher inlet temperature of thermal air led to a lower concentration of residual methanol, but also a higher concentration of generated CO from the reformer exit. The choices of operating conditions were limited to ensure a tolerable concentration of methanol and CO in H2-rich gas for feeding into a high temperature polymer electrolyte membrane fuel cell (HT-PEMFC) stack. With fixed catalyst load, the increase of tube number and decrease of tube diameter improved the methanol conversion, but also increased the CO concentration in reformed gas. In addition, increasing the number of baffle plates in the shell side increased the methanol conversion and the CO concentration.

The Kinetic Study on Phosphorous Acid Reducing Adamsite

2012 ◽  
Vol 550-553 ◽  
pp. 2699-2703
Author(s):  
Xin Wang ◽  
Zhong Lin Cai ◽  
Shan Mao Li ◽  
Ji Zhang Wang ◽  
Wei Li ◽  
...  
Keyword(s):  
Reaction Mechanism ◽  
Kinetic Study ◽  
Rate Equation ◽  
Theoretical Basis ◽  
Reaction Rate ◽  
Phosphorous Acid ◽  
Reduction Reaction ◽  
Kinetic Process ◽  
Reaction Rate Equation

The kinetic process of the reduction reaction between phosphorous acid and adamsite has been studied to determine the reaction rate equation and to deduce the reaction mechanism, providing the theoretical basis for destroying adamsite by phosphorous acid.

scholarly journals Time Fractional Fisher–KPP and Fitzhugh–Nagumo Equations

Entropy ◽  
2020 ◽  
Vol 22 (9) ◽  
pp. 1035
Author(s):  
Christopher N. Angstmann ◽  
Bruce I. Henry
Keyword(s):  
Diffusion Equation ◽  
Reaction Kinetics ◽  
Rate Equation ◽  
Reaction Rate ◽  
Reaction Diffusion ◽  
Reaction Diffusion Equations ◽  
Mass Action ◽  
Diffusion Equations ◽  
Mixed Systems ◽  
Reaction Rate Equation

A standard reaction–diffusion equation consists of two additive terms, a diffusion term and a reaction rate term. The latter term is obtained directly from a reaction rate equation which is itself derived from known reaction kinetics, together with modelling assumptions such as the law of mass action for well-mixed systems. In formulating a reaction–subdiffusion equation, it is not sufficient to know the reaction rate equation. It is also necessary to know details of the reaction kinetics, even in well-mixed systems where reactions are not diffusion limited. This is because, at a fundamental level, birth and death processes need to be dealt with differently in subdiffusive environments. While there has been some discussion of this in the published literature, few examples have been provided, and there are still very many papers being published with Caputo fractional time derivatives simply replacing first order time derivatives in reaction–diffusion equations. In this paper, we formulate clear examples of reaction–subdiffusion systems, based on; equal birth and death rate dynamics, Fisher–Kolmogorov, Petrovsky and Piskunov (Fisher–KPP) equation dynamics, and Fitzhugh–Nagumo equation dynamics. These examples illustrate how to incorporate considerations of reaction kinetics into fractional reaction–diffusion equations. We also show how the dynamics of a system with birth rates and death rates cancelling, in an otherwise subdiffusive environment, are governed by a mass-conserving tempered time fractional diffusion equation that is subdiffusive for short times but standard diffusion for long times.

Sign in / Sign up

Export Citation Format

Share Document