H 2 - CEA

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22 Φεβ 2014 (πριν από 3 χρόνια και 7 μήνες)

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1
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639

Florent Jomard
Commissariat à l’Énergie Atomique
DEN/DTEC/STCF/LGCI
Site de Marcoule BP 17171
30207 Bagnols sur Cèze, France
Jean-Pierre Feraud
Commissariat à l’Énergie Atomique
DEN/DTEC/STCF/LGCI
Site de Marcoule BP 17171
30207 Bagnols sur Cèze, France
Jacques Morandini
Astek Rhone-Alpes
1 place du Verseau
38130 Echirolles, France
Yves Du Terrail Couvat
Laboratoire EPM, Madylam
1340 Rue de la Piscine
Domaine Universitaire
38400 Saint Martin d’Hères, France
Jean-Pierre Caire
LEPMI, ENSEEG
1130 Rue de la Piscine
38402 Saint Martin d’Hères, France
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE
HYBRID CYCLE USING TWO COUPLED CODES

2
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
I.
Introduction
II.
The Westinghouse sulfur cycle
III.
Modeling aim
IV.
Coupling of physical phenomena
with Fluent
®
/ Flux Expert
®
codes
V.
Electrolyzer modeling, boundary conditions
VI.
Software coupling results
VII.
Conclusion, future prospect

3
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
Global warming context requires decreasing world's greenhouse gas emission
I.
Introduction
hydrogen
alternative solution to replace primary energy
Exemple :
Hydrogen + fuel cells can replace internal combustion engines
CEA / PSA Fuel cells : GENEPAC

( GENérateur Electrique de Pile A Combustible)
PSA hydrogen concept car
(
207 ePure)

4
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
wide uses of energy =

hydrogen

mass production
High temperature cycles for hydrogen production
- 100% thermochemical : Bunsen Cycle…
- hybride cycle (
Westinghouse sulfur cycle
, Deacon cycle…)
- 100% electrochemical cycle (high temperature electrolysis of water)
I.
Introduction
High temperature hydrogen production technologies could be provided by
using
:
- Gen. IV Nuclear power plants
- Thermal solar facilities…

5
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
H
2
,
product
½ O
2
by product
II.

The Westinghouse sulfur cycle

Hybrid Sulfur Process block
H
2
O
feed
Thermal
energy

Filter press


Electrolyzer

(50 – 100°C)
Concentration
Évaporation
Décomposition
Absorption
300°C

Concentration
300°C
Thermal

Decomposition 850°C

Evaporation
600°C
Thermal
energy
Thermal
energy
H
2
O + SO
2
+ ½ O
2

H
2
SO
4
Electrical energy

Compression
H
2
SO
4
part
SO
2
part
H
2
SO
4
SO
2

Cooling
SO
2
H
2
O
SO
2
H
2
O
SO
2
H
2
O
Absorption
25°C
Westinghouse sulfur
Westinghouse sulfur
cycle
cycle

6
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
Process working conditions
-
T°C : 50 - 100°C
-

[H
2
SO
4
] : 20 - 60 %
weight
-

PSO
2
1 bar
- Current density 200 mA/cm²
H
+
H
+
H
+
H
+
H
+
H
+
H
+
H
+
H
+
e
-
II.

The Westinghouse sulfur cycle
membrane
Two compartment membrane electolysis cell
:
Anode
Anode
+
+
Cathode
Cathode
-
-
SO
SO
2
2
H
H
2
2
SO
SO
4
4
H
H
+
+
H
H
2
2
Anolyte : H
2
O-SO
2
- H
2
SO
4
Catholyte: H
2
O – H
2
SO
4
SO
2
+ 2H
2
O

H
2
SO
4
+ 2H
+
+ 2e
-


2H
+
+ 2e
-

H
2

7
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
Within the framework of the Westinghouse cycle studies
The aim of our works consists of modeling a filter press electrolyzer
for hydrogen production.
III.
Modeling aim
Our studies have to take into account numerous physical interactions :
- electrokinetic (overpotential),
- thermal behaviour (Joule effect),
- fluid dynamics (forced convection),
- multiphasic flow (electrolyte + bubble plume).
We expect that the virtual filter press design will work as a real one

8
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
IV.

Coupling of physical phenomena with
Fluent
®
/ Flux Expert
® codes
( )
( ) 0
( ) ( )
p V S S
u
u u g
t
u
t
T
c u T k T Q Q
t

       


   

            
r
r r
r r r
r
r
r r r
r
   



 

Physical phenomena :
- Thermohydraulics (Fluent, finite volume method)
Navier-Stokes continuity equations


Heat transfert equation
- CFD, Fluent model selected
- k-
ε
turbulence model so-called « realizable »
- diphasic flow description : Euler-Euler 
- separate phase :  disperse phases 












n
p
pq
q
q
q
q
q
m
v
t
1












q
q
q
n
p
pq
pq
qp
q
q
q
r
q
q
q
q
q
q
q
q
F
v
m
R
g
p
v
v
v
t



































1
momentum
Diphasic fluid dynamic
(1)
(1)
(2)
(2)

9
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
0

=
V)
(-
.





.V
-
j






IV.

Coupling of physical phenomena with
Fluent
®
/ Flux Expert
® codes
Physical phenomena
(continuation)
:
- Electrokinetics (Flux-Expert, finite element method)
Charge Balance, Laplace equation :
Ohm's Law, primary current distribution (a):
















RT
nF
RT
nF
e
e
j
j
)
1
(
0
Secondary current distribution, Butler-Volmer's Law (b) :
Elec
trode
Electrolyte

(j)
Potential
(V)
Cell width
(a)
Interface

gap


)
j
(
f
j
n
n
ei



(1)
(1)
(2)
(2)
(b)
(a)

10
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
IV.

Coupling of physical phenomena with
Fluent
®
/ Flux Expert
® codes
Software coupling :

FLUENT
®

UDF

Swap
functions

Main
memory

Data

files

FEcoupling.c UDF

FEcoupling.c

Property

operators

:

prxxxx.F

FLUX
EXPERT
®

Main
memory

Swap
functions

Main
memory

Main
memory

Fluent
®
–Flux Expert
®
coupling flowchart


= message-passing function

physical phenomena can be
solved by using different meshes
(structured or unstructured)

Communication between the two
codes : simple and robust message-
passing library



algorithms developed are mainly
location and interpolation algorithms


11
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
FLUENT
®
Solve the two phase
Thermohydraulic problem
Calculation of
Temp. (K)
in all the domain
u
(flow velocity)
α
g

(
hydrogen concentration)
FLUX EXPERT
®
Solve the

Electrokinetic
problem
Calculation of

U : Potential (V)

J : current densities (A.m
-2
)

Qs/Qv : Thermal Joule effect
( W.m
-3
)
Thermal and current densities
inputs
hydrogen concentration
Temperature
IV.

Coupling of physical phenomena with
Fluent
®
/ Flux Expert
®
codes

12
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
V.

Electrolyzer modeling, boundary conditions
The FM01-LC laboratory scale electrolyzer
:
:

0.16m
0.04m
0.013m
H
+
+H
2
SO
4
H
2
SO
4
+

SO
2
H
2
SO
4
+ SO
2
H
2
SO
4
H
2
+
-





z
x
y
Electrolyzer operating principle
With :


cathode,

hydrogen release area ,

catholyte,

membrane,

anolyte,


anode
.
.

13
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
V.

Electrolyzer modeling, boundary conditions
CATHOLYTE
CATHODE
memb
ran
AN
O
LYTE
ANODE
Overpotential Area
0 V
Y (mm)
Overpotential Area
Z (mm)
2000
A.m
-2
CATHOLYTE
CA
THODE
m
embrane
A
NOLYTE
ANODE
Flux-Expert
Hydrogen bubbles velocity : 0.01m.s
-1
bubble
emission angle : 45°
Electrolyte uniform velocity profile

,

,k,c
p
: temperature dependent
No thermal exchange with outside
Hydrogen
area
160 mm
V= 0.07m.s
-1
T=323K
V= 0.07m.s
-1
T=323K
CATHOLYTE
C
A
THODE
membrane
ANOLYTE
AN
OD
E
0 1.5 6.5 6.6 11.2 13 mm
Fluent


Boundary conditions to produce 5 Nl.h
-1
of hydrogen

14
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
1
2
3
VI.

Numerical results


Residuals continuity



u
residual sulphuric acid




u

residual hydrogen




v

residual sulphuric acid



v

residual hydrogen




w

residual sulphuric acid



w

residual hydrogen




T
1

residual sulphuric acid




T
2

residual hydrogen




K

residual sulphuric acid





residual sulphuric acid



(1–
K
)
residual hydrogen
FLUENT iterations
Code Coupling Behavior


Interaction between the two codes is demonstrated by the convergence of the
computational residuals with successive iterations


FLUX-EXPERT iterations

15
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
T =323 K
υ = 0.069 m.s
-1
T =323 K
υ = 0.069 m.s
-1
0.16
m
0 m
VI.

Numerical results

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

322

324

326

Anolyte

Catholyte



Temperature (K)

Height (m)

Thermal problem :
Graded colors
scale
Temp. (K)

16
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
3 mm
VI.

Numerical results
Catholyte
C
athode
% H
2
(vol.)
Cathode
Anode
membrane
Hydrogen plume area
approx. 1 mm
Diphasic problem resolution :

Hydrogen volume fraction < 72%



Maximum concentation at 0.2 mm
from cathode

17
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
VI.

Numerical results
% H
2
(vol.)
Cathode
Anode
Graded colors
scale
0
10
20
30
40
50
60
70
80
0.0014
0.0019
0.0024
0.0029
0.0034
distance from cathode (m)
h
y
d
r
o
g
e
n

c
o
n
c
e
n
t
r
a
t
i
o
n

(
%
)
h_0.15
h_0.08
h_0.01
height =
0.15m
height =
0.08m
height =
0.01m
Diphasic problem resolution :

18
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
Anolyte
VI.

Numerical results
Fluid dynamic calculation :
Anolyte flow appearance:
Flat (uniform velocity) + wall effect
on membrane and anode sides


Caracteristic of turbulent flow

Catholyte flow appearance :
Wall effect on membrane side,
High velocity increasing on cathode
side (X4)


Characteristic of air lift effect
Catholyte
Flow m.s
-1
membrane

19
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
Anodic overpotential = 70 % tension of cell
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0
0.002
0.004
0.006
0.008
0.01
0.012
0.014
Lenght (m)
E
le
c
tri
c
a
l
po
te
nt
ial (V
)
0,73 V
cathodic
over
potential
anodic
over
potential
0.47 V
Tension of cell : 0.73V
Goal :

Design a cell to obtain
0.6 V of total tension
VI.

Numerical results
Electrokinetics calculation :
Potential (
V)
V)

20
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
Modeling with Flux-Expert / Fluent Codes


Performed with message-passing library


Only 24h of calculation on Pentium IV(F. Expert) + Core 2 Duo (Fluent) PC
CFD results


Electrolyte rising temperature : 4°C


Catholyte motion (x4), hydrogen bubbly effect
Electrokinetics calculation


Electrochemical irreversible process taken into account with Flux Expert®


Total cell tension obtained : 0.73V (in accordance with literature results)
VI.


Conclusion, future prospect

21
/21

DEN/VRH/DTEC/STCF/LGCI
JP FERAUD
ICONE15, Nagoya 2007 April 22-26
MODELING A FILTER PRESS ELECTROLYZER FOR THE WESTINGHOUSE HYBRID CYCLE USING TWO COUPLED CODES
ICONE15 -10639
VI.


Conclusion, future prospect
Calculation / Experiments


Experiments required to complete the lack of anodic overpotential law


Check
Validity of diphasic flow behavior


development of specific physical operators


modelling a stack of cells before scaling-up


Optimization of the future
electrochemical process with a design
of numerical experiments