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%.

Microchannel structure design for hydrogen supply from methanol steam reforming

2022 ◽  
Vol 429 ◽  
pp. 132286
Author(s):  
Weiqin Lu ◽  
Rongjun Zhang ◽  
Sam Toan ◽  
Ran Xu ◽  
Feiyi Zhou ◽  
...  
Keyword(s):  
Steam Reforming ◽  
Structure Design ◽  
Methanol Steam Reforming ◽  
Hydrogen Supply

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.

scholarly journals Evaporation of Methanol Solution for a Methanol Steam Reforming System

Energies ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4862
Author(s):  
Ngoc Van Trinh ◽  
Younghyeon Kim ◽  
Hongjip Kim ◽  
Sangseok Yu
Keyword(s):  
Cylindrical Shell ◽  
Steam Reforming ◽  
Heat Exchangers ◽  
Methanol Conversion ◽  
Methanol Solution ◽  
Methanol Steam Reforming ◽  
Field Mode ◽  
Methanol Reforming ◽  
Shell And Tube ◽  
Fundamental Requirement

In a methanol-reforming system, because the mixture of methanol and water must be evaporated before reaching the reforming reaction zone, having an appropriate evaporator design is a fundamental requirement for completing the reforming reaction. This study investigates the effect of the evaporator design for the stable reforming of methanol–water mixtures. Four types of evaporator are compared at the same heat duty of the methanol-reforming system. The four evaporators are planar heat exchangers containing a microchannel structure, cylindrical shell-and-tube evaporators, zirconia balls for internal evaporation, and combinations of cylindrical shell-tubes and zirconia balls. The results show that the evaporator configuration is critical in performing stable reform reactions, especially for the flow-field mode of the evaporator. Additionally, the combination of both internal and external evaporation methods generates the highest performance for the methanol-reforming system, with the methanol conversion reaching almost 98%.

Parameter Study of Steam Methanol Reforming With Cu/ZnO/Al2O3 Catalyst in a Microchannel Reactor

2009 ◽  
Author(s):  
Chun-I Lee ◽  
Huan-Ruei Shiu ◽  
Wen-Chen Chang ◽  
Fang-Hei Tsau
Keyword(s):  
Wall Temperature ◽  
Steam Reforming ◽  
Catalyst Layer ◽  
Methanol Conversion ◽  
Channel Length ◽  
Methanol Steam Reforming ◽  
Distribution Analysis ◽  
Methanol Reforming ◽  
Conversion Rates ◽  
Al2o3 Catalyst

Three-dimensional numerical simulations were performed to investigate the effect of methanol conversion and hydrogen product of a microchannel methanol steam reformer under various parameter conditions. In this simulation, the wall temperature of reactor (Tw), inlet flow rate of reactant, the different S/C ratios (steam to carbon ratio) and the thickness of the catalyst layer were taken into account to analyze product concentration and conversion rates along the channel length. The methanol conversion for methanol steam reforming on Cu/ZnO/Al2O3 catalyst was carried out at reaction temperature ranging from 200 to 260° under an atmospheric pressure. Furthermore, the reaction schemes considered the methanol steam reforming reaction and the reverse water gas-shift reaction. Regarding the distribution analysis of methanol reforming, the methanol conversion (η) and the product of hydrogen increase with the increase in wall temperature from 200 to 260°C and lower reactant flow rates. However, the result shows the methanol conversion increases and the hydrogen product decreases with less feed-in amount of methanol as the higher S/C. Additionally, the methanol conversion increase with higher thickness of catalyst layer from 10 to 70μm. The product of hydrogen, therefore, reaches a consistent distribution above 40μm along the channel length. Nevertheless, all of the operation parameter of exhaust stream at the reformer exit has the following composition: 75% H2, 24% CO2 and less than 1% CO. This research attempts to reveal a simplified methanol reforming model, which analyze the significant behavior and product distribution in qualitative/quantitative along the channel.

Flame-Made CuO/ZnO/Al2O3 Catalyst for Methanol Steam Reforming

2013 ◽  
Author(s):  
Emmanuel Lim ◽  
Teeravit Visutipol ◽  
Wen Peng ◽  
Nico Hotz
Keyword(s):  
Carbon Monoxide ◽  
Spray Pyrolysis ◽  
Steam Reforming ◽  
Methanol Conversion ◽  
Flame Spray Pyrolysis ◽  
Spray Pyrolysis Method ◽  
Methanol Steam Reforming ◽  
Flame Spray ◽  
Inlet Flow ◽  
Flow Rates

In the present study, a catalyst produced by flame spray pyrolysis (FSP) was evaluated for its ability to produce hydrogen-rich gas mixtures. Catalyst particles fabricated by a novel flame spray pyrolysis method resulting in a highly active catalyst with high surface-to-volume ratio were compared to a commercially produced catalyst (BASF F3-01). Both catalysts consisted of CuO/ZnO/Al2O3 of identical composition (CuO 40wt%, ZnO 40wt%, Al2O3 20wt%). Reaction temperatures between 220 and 295 °C, methanol-water inlet flow rates between 2 and 50 μl/min, and reactor masses between 25 and 100 mg were tested for their effect on methanol conversion and the production of undesired carbon monoxide. 100% methanol conversion can be easily achieved within the operational conditions mentioned for this flame-made catalyst — at reactor temperatures of 255 °C (achievable with non-concentrating solar collectors) more than 80% methanol conversion can be reached for methanol-water inlet flow rates as high as 10 μl/min. The FSP catalyst demonstrates similar catalytic abilities as the BASF, produces a consistent gas composition and produces lower overall CO production. Furthermore, the FSP catalyst demonstrates a better suitability to fuel cell use through its higher resistance to degradation and smaller production of carbon monoxide over long-term use. In the present study, the merits of using flame spray pyrolysis to produce CuO/ZnO/Al2O3 methanol steam reforming catalysts are examined, and directly compared to catalysts that are commercially produced in bulk pellet form, and then ground and sieved. The comparison is performed from several different perspectives: catalytic activity and CO production at various temperatures and fuel inlet flow rates; surface and structure characteristics are determined via scanning electron and transmission electron microscopy; surface area characteristics are determined via BET tests.

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.

Flame-Made Catalyst for Bio-Methanol Steam Reforming

2013 ◽  
Author(s):  
Nico Hotz
Keyword(s):  
Carbon Monoxide ◽  
Spray Pyrolysis ◽  
Steam Reforming ◽  
Methanol Conversion ◽  
Flame Spray Pyrolysis ◽  
Spray Pyrolysis Method ◽  
Methanol Steam Reforming ◽  
Flame Spray ◽  
Inlet Flow ◽  
Flow Rates

In the present study, a catalyst produced by flame spray pyrolysis (FSP) was evaluated for its ability to produce hydrogen-rich gas mixtures. Catalyst particles fabricated by a novel flame spray pyrolysis method resulting in a highly active catalyst with high surface-to-volume ratio were compared to a commercially produced catalyst (BASF F3-01). Both catalysts consisted of CuO/ZnO/Al2O3 of identical composition (CuO 40wt%, ZnO 40wt%, Al2O3 20wt%). Reaction temperatures between 220 and 295 °C, methanol-water inlet flow rates between 2 and 50 μl/min, and reactor masses between 25 and 100 mg were tested for their effect on methanol conversion and the production of undesired carbon monoxide. 100% methanol conversion can be easily achieved within the operational conditions mentioned for this flame-made catalyst — at reactor temperatures of 255 °C (achievable with non-concentrating solar collectors) more than 80% methanol conversion can be reached for methanol-water inlet flow rates as high as 10 μl/min. The FSP catalyst demonstrates similar catalytic abilities as the BASF, produces a consistent gas composition and produces lower overall CO production. Furthermore, the FSP catalyst demonstrates a better suitability to fuel cell use through its higher resistance to degradation and smaller production of carbon monoxide over long-term use. In the present study, the merits of using flame spray pyrolysis to produce CuO/ZnO/Al2O3 methanol steam reforming catalysts are examined, and directly compared to catalysts that are commercially produced in bulk pellet form, and then ground and sieved. The comparison is performed from several different perspectives: catalytic activity and CO production at various temperatures and fuel inlet flow rates; surface and structure characteristics are determined via scanning electron and transmission electron microscopy; surface area characteristics are determined via Brunauer-Emmett-Teller (BET) tests.

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