Because of the potential for high efficiency and low emissions, hydrogen powered systems are considered to be the next generation power source for both stationary and transportation applications. Providing a hydrogen source is a critical challenge. Steam reforming processes are demonstrated for producing hydrogen for fuel cell and other applications. Generating hydrogen via steam reformation requires that heat energy be transferred to the reactants to support the endothermic reaction. For a cylindrical steam-reforming reactor, large thermal gradients between the heat source (reactor wall) and reactor centerline create a nonideal condition for complete conversion. This gradient is caused by insufficient heat transfer inside the catalyst bed. Passive flow disturbance inside the catalyst bed is a potential method to enhance the heat and mass transfer in the steam-reforming process. This paper presents experimental research that investigates the effect of changing the flow pathway inside the reactor to improve the heat and mass transfer and thus enhance fuel conversion. Based on the experimental results, a 14% increase of methanol fuel conversion was achieved via the passive flow disturbance enhancement. The tradeoff was an extra pressure drop of 2.5 kPa across the reactor. A 30 h experimental run does not show a significant change in degradation rate for the passive flow disturbance. The results of this study contribute to the improvement of reformer design for better fuel processing system performance.

1.
Docter
,
A.
, and
Lamm
,
A.
, 1999, “
Gasoline Fuel Cell Systems
,”
J. Power Sources
0378-7753,
84
, pp.
194
200
.
2.
Joensen
,
F.
, and
Rostrup-Nielsen
,
J. R.
, 2002, “
Conversion of Hydrocarbons and Alcohols for Fuel Cells
,”
J. Power Sources
0378-7753,
105
(
2
), pp.
195
201
.
3.
Simmons
,
T. C.
,
Erickson
,
P. A.
,
Heckwolf
,
M. J.
, and
Roan
,
V. P.
, 2002, “
The Effects of Start-up and Shutdown of a Fuel Cell Transit Bus on the Drive Cycle
,” SAE Technical Paper Series, Paper No. 2002-01-0101.
4.
Ledjeff-Hey
,
K.
,
Formanski
,
V.
,
Kalk
,
T.
, and
Roes
,
J.
, 1998, “
Compact Hydrogen Production Systems for Solid Polymer Fuel Cells
,”
J. Power Sources
0378-7753,
71
, pp.
199
207
.
5.
Peppley
,
B. A.
,
Amphlett
,
J. C.
,
Kearns
,
L. M.
,
Mann
,
R. F.
, and
Roberge
,
P. R.
, 1997, “
Hydrogen Generation for Fuel Cell Power Systems by High-Pressure Catalytic Methanol-Steam Reforming
,”
Proceedings of the Intersociety Energy Conversion Engineering Conference
, Honolulu, July 27-August 1, Paper No. IECEC 97093.
6.
Erickson
,
P. A.
, and
Roan
,
V.
, 2003, “
Enhancing Hydrogen Production for Fuel Cell Vehicles by Superposition of Acoustic Fields on the Reformer: A Preliminary Study
,” SAE Technical Paper Series, Paper No. 2003-01-0806.
7.
Nakagaki
,
T.
,
Ogawa
,
T.
,
Murata
,
K.
, and
Nakata
,
Y.
, 2001, “
Development of Methanol Steam Reformer for Chemical Recuperation
,”
ASME J. Eng. Gas Turbines Power
0742-4795,
123
, pp.
727
733
.
8.
Usami
,
Y.
,
Fukusako
,
S.
, and
Yamada
,
M.
, 2003, “
Heat and Mass Transfer in a Reforming Catalyst Bed: Analytical Prediction of Distributions in the Catalyst Bed
,”
Heat Transfer Asian Res.
1099-2871,
32
(
4
), pp.
367
380
.
9.
Wakao
,
N.
, and
Kaguei
,
S.
, 1982,
Heat and Mass Transfer in Packed Beds
,
Gordon and Breach Science
, New York, p.
161
.
10.
Fogler
,
H. S.
, 1999,
Elements of Chemical Reaction Engineering
,
3rd
ed.,
Prentice–Hall ECS Professional
, Upper Saddle River, NJ, p.
768
.
11.
Zhang
,
X. R.
,
Shi
,
P.
,
Zhao
,
J.
,
Zhao
,
M.
, and
Liu
,
C.
, 2003, “
Production of Hydrogen for Fuel Cells by Steam Reforming of Methanol on Cu∕ZrO2∕Al2O3 Catalyst
,”
Fuel Process. Technol.
0378-3820,
83
, pp.
183
192
.
12.
Sapre
,
A. V.
, 1997, “
Catalyst Deactivation Kinetics From Space-Velocity Experiments
,”
Chem. Eng. Sci.
0009-2509,
52
(
24
), pp.
4615
4623
.
13.
Takeda
,
K.
,
Baba
,
A.
,
Hishinuma
,
Y.
, and
Chikahisa
,
T.
, 2002, “
Performance of a Methanol Reforming System for a Fuel Cell Powered Vehicle and System Evaluation of a PEFC System
,”
JSAE Rev.
0389-4304,
23
(
2
), pp.
183
188
.
14.
Erickson
,
P. A.
, 2002, “
Enhancing the Steam-Reforming Process With Acoustics: An Investigation for Fuel Cell Vehicle Application
,” Ph.D. dissertation, University of Florida, Gainesville, FL.
15.
Davieau
,
D. D.
, 2004, “
An Analysis of Space Velocity and Aspect Ratio Parameters in Steam-Reforming Hydrogen Production Reactors
,” M.S. thesis, University of California, Davis, CA.
16.
DeWitt
,
D. P.
, 2001,
Introduction to Heat Transfer
,
4th ed.
,
Wiley
, New York, p.
447
.
17.
Nagano
,
S.
,
Miyagawa
,
H.
,
Azegami
,
O.
, and
Oshawa
,
K.
, 2001, “
Heat Transfer Enhancement in Methanol Steam Reforming for a Fuel Cell
,”
Energy Convers. Manage.
0196-8904,
42
, pp.
1817
1829
.
18.
Li
,
C. H.
, and
Finlayson
,
B. A.
, 1977, “
Heat Transfer in Packed Beds
,”
Chem. Eng. Sci.
0009-2509,
32
(
9
), pp.
1055
1066
.
19.
Tonkivich
,
A. Y.
,
Zilka
,
J. L.
,
LaMont
,
M. J.
,
Wang
,
J.
, and
Wegeng
,
R. S.
, 1999, “
Microchannel Reactors for Fuel Processing Applications I. Water Gas Shift Reactor
,”
Chem. Eng. Sci.
0009-2509,
54
, pp.
2947
2951
.
20.
Faungnawakij
,
K.
,
Kikuchi
,
R.
, and
Eguchi
,
K.
, 2006, “
Thermodynamic Evaluation of Methanol Steam Reformation for Hydrogen Production
,”
J. Power Sources
0378-7753, in press.
21.
Gallucci
,
F.
, and
Basile
,
A.
, 2006, “
Co-current and Counter-Current Modes for Methanol Steam Reforming Membrane Reactor
,”
Int. J. Hydrogen Energy
0360-3199, in press.
22.
Lin
,
Y.-M.
, and
Rei
,
M.-H.
, 2001, “
Study on the Hydrogen Production From Methanol Steam Reforming in Supported Palladium Membrane Reactor
,”
Catal. Today
0920-5861,
67
, pp.
77
84
.
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