Institute of Chemical Engineering
Zero Emission Technologies
Evaluation of an improved dual circulating fluidized
bed reactor design for chemical looping combustion
Karl Mayer, Stefan Penthor, Ellen Schanz, Michael Stollhof, Hermann Hofbauer
6th High Temperature Solid Looping Network Meeting
Milan, September 1-2, 2015
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Outlook
2
• Introduction
• Data used for the new design
• The new pilot plant
• Results of benchmarking against the old reactor
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Introduction
3
>1000 h of CLC operation in a 120kW pilot plant with different oxygen
carrier materials
- performance of each material was different
- some trends were the same for all materials
- the reactor system had a potential for further optimization
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Introduction: Reference numbers
4
in,FR,CHinFR,
exh,FR,CHexhFR,
CH
4
4
4yn
yn1X
reactor fuel to carbon total
exhaust reactor fuel in CO2
CO 2Carbon dioxide yield:
Methane conversion:
Oxygen carrier to fuel ratio: 2
2
accessible O from oxygen carrier=
O demand fuel
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Outlook
5
• Introduction
• Data used for the new design
• The new pilot plant
• Results of benchmarking against the old reactor
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Data used for the new design:Fe and Cu based oxygen carriers
6
0 1 2 360
65
70
75
80
CH
4 c
on
ve
rsio
n, C
O2 y
ield
[%
]
[-]
XCH4
YCO2
1 2 3 4 5 630
40
50
60
CH
4 c
on
ve
rsio
n, C
O2 y
ield
[%
]
[-]
XCH4
YCO2
Mayer K et al. The different demands of oxygen carriers on the reactor system of a CLC plant – Results of oxygen carrier
testing in a 120 kWth pilot plant. Appl Energy (2015), http://dx.doi.org/10.1016/j.apenergy.2015.07.053
Fe17 Cu14
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Data used for the new design:Fe and Cu based oxygen carriers
7
100 150 200 250 30050
60
70
80
90
CH
4 c
on
ve
rsio
n, C
O2 y
ield
[%
]
Specific FR inventory [kg/MW]
XCH4
YCO2
Fe17 Cu14
100 200 300 40030
40
50
60
70
XCH4
Fe17large
YCO2
Fe17large
XCH4
Fe17small
YCO2
Fe17small
CH
4 c
on
ve
rsio
n, C
O2 y
ield
[%
]
Specific FR inventory [kg/MW]
Mayer K et al. The different demands of oxygen carriers on the reactor system of a CLC plant – Results of oxygen carrier
testing in a 120 kWth pilot plant. Appl Energy (2015), http://dx.doi.org/10.1016/j.apenergy.2015.07.053
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Data used for the new design:Clou oxygen carriers
8
C14 C28
0 10 20 30 4070
80
90
100
CH
4 c
on
ve
rsio
n, C
O2 y
ield
[%
]
[-]
XCH4
YCO2
0 10 20 30 4070
80
90
100
CH
4 c
on
ve
rsio
n, C
O2 y
ield
[%
]
[-]
XCH4
YCO2
Mayer K et al. The different demands of oxygen carriers on the reactor system of a CLC plant – Results of oxygen carrier
testing in a 120 kWth pilot plant. Appl Energy (2015), http://dx.doi.org/10.1016/j.apenergy.2015.07.053
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Data used for the new design:Clou oxygen carriers
9
0 100 200 300 40070
80
90
100
XCH4
YCO2
CH
4 c
on
ve
rsio
n, C
O2 y
ield
[%
]
Specific FR inventory [kg/MW]
0 100 200 300 40070
80
90
100
XCH4
YCO2
CH
4 c
on
ve
rsio
n, C
O2 y
ield
[%
]
Specific FR inventory [kg/MW]
C14 C28
Mayer K et al. The different demands of oxygen carriers on the reactor system of a CLC plant – Results of oxygen carrier
testing in a 120 kWth pilot plant. Appl Energy (2015), http://dx.doi.org/10.1016/j.apenergy.2015.07.053
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Outlook
10
• Introduction
• Data used for the new design
• The new pilot plant
• Results of benchmarking against the old reactor
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Old vs. New Design: Specifications
11
unit old design new design
AR FR AR FRlow FRup
reactor diameter mm 150 159.3 129.7 179.5 102.3
reactor height m 4.1 3 4.03 0.75 3.05
inlet gas flow Nm³/h 140 12 140 12
outlet gas flow Nm³/h 114 36 114 36
temperature °C 940 850 950 950
archimedes number - 7.55 9.13 6.9 6.78
superficial velocity m/s 7.3 2.1 9.8 1.8 5.5
U/Umf - 1280 315 267 1876 975
fuel power (n.g.) kW 120 120
air/fuel ratio - 1.2 1.2
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Old vs. New Design: Reactors
12
fue
lre
act
or
air
rea
cto
r
inte
rna
l lo
op
se
al
up
pe
r lo
op
se
al
lo w er loop se a lstea m
stea m
stea m
fuelprim.
a i r
se c.
a i r
a ir rea ctoro ff gas fu e l rea ctor
o ff gas
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Old vs. New Design: Loop Seal
13
AR
do
wn
co
me
r
AR
do
wn
co
me
r
to FRto FR
old new
we
ir h
eig
ht
we
ir h
eig
ht
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Outlook
14
• Introduction
• Data used for the new design
• The new pilot plant
• Results of benchmarking against the old reactor
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Oxygen carrier used for benchmark campaign
15
Mixture of 60wt.% C14 and 40wt.% C28
C14 C28
Active metal oxide [-] CaMn0.9Mg0.1O3-δ CaMn0.775Mg0.1Ti0.125O3-δ
Active metal oxide
contentwt% - -
Particle size [µm] 130 160
Bulk density [kg/m³] 1540 1220
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Results: Gas leakage between reactors
16
0
0.25
0.5
0.75
1
0 20 40 60 80 100 120
leak
age
VN
2[N
m³/
h]
Gs [kg/m²s]
C28
Cu Carrier
C14
Fe17
Ni Carrier
New Design
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Results: Specific FR - Inventory
17
75
80
85
90
95
100
0 100 200 300 400
CH
4convers
ion,
CO
2yie
ld [
%]
Specific FR inventory[kg/MW]
XCH₄
YCO₂
XCH₄,C14
YCO₂,C14
XCH4,C28
YCO2,C28
XCH4
YCO2
XCH4
YCO2
XCH4
YCO2
new design
C14
C28
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Results: OC / fuel ratio
18
70
75
80
85
90
95
100
5 10 15 20 25 30 35
CH
4convers
ion,
CO
2yie
ld [
%]
[-]
XCH₄
YCO₂
XCH₄,C14
YCO₂,C14
XCH4,C28
YCO2,C28
XCH4
YCO2
XCH4
YCO2
XCH4
YCO2
new design
C14
C28
Karl MayerMilan, September 1-2, 2015
Institute of Chemical Engineering
Zero Emission Technologies
Thank you
19