The potential of water-gas shift membrane
reactors for CtX and flexible poly-generation
processes
7th International Freiberg/Inner Mongolia Conference
on IGCC & XtL Technologies, Coal Conversion and Syngas
9 June 2015, Inner Mongolia, China
Alexander Buttler, Hartmut Spliethoff
Institute for Energy Systems, Technical Universtiy of Munich
Structure
Transition of the German Energy System
• Actual challenge of volatile renewable feed-in
• Future demand of flexible power plants and resulting requirements
The potential of IGCC poly-generation plants in a changing energy system
Water-gas shift membrane reactor
• Theory
• Flexible poly-generation concept
Modelling and analysis
• Modelling appraoch and boundary conditions
• Concept evaluation
7th international Freiberg/Inner Mongolia Conference on IGCC&XtL Technologies, Alexander Buttler09.06.15 2
Transformation of the German energy system
7th international Freiberg/Inner Mongolia Conference on IGCC&XtL Technologies, Alexander Buttler
Installed capacity of wind and PV
0
20
40
60
80
100
120
140
160
1995 2000 2005 2010 2015 2020 2025 2030 2035 2040 2045 2050
Pow
er
[GW
]
Solar Wind Offshore Wind Onshore
Peak net load
Installed Wind and PV power will exceed
peak load next year
09.06.15 3
Actual challenge of volatile renewable feed-in
7th international Freiberg/Inner Mongolia Conference on IGCC&XtL Technologies, Alexander Buttler
Impact of wind and PV on the residual load
82,587,0 85,8
81,2 80,983,9
73,2 72,976,3
39,2 39,1 38,7
19,5 20,518,2
11,6 12,5 10,6
0
10
20
30
40
50
60
70
80
90
2014 2013 2012
Tite
l
Load Max
Res1 Max
Res2 Max
Load Min
Res1 Min
Res2 Min
0
10
20
30
40
50
60
70
80
90
0 1000 2000 3000 4000 5000 6000 7000 8000
Po
wer
[GW
]
hours per year
Biomass, hydro Wind+PV Load Res2 Res1
Strong lowering of minimal residual load
Little decrease of residual peak load
09.06.15 4
Actual challenge of volatile renewable feed-in
7th international Freiberg/Inner Mongolia Conference on IGCC&XtL Technologies, Alexander Buttler
Inflexibilities of the conventional power plants - negative electricity prices
0
10
20
30
40
50
60
70
80
Jan. März Mai Juli Sept. Nov.
nuclear Lignite Hard coal Gas OilNet power [GW]
12,17,5
19,6
9,2
20,9
21,4
3,5
1,0
Max Min
79,9
23,6
March May July-80
-60
-40
-20
0
20
40
60
80
100
0 10 20 30 40 50 60 70 80
Da
y-A
he
ad
Sp
ot m
ark
et p
rice
[€
/MW
h]
Residual load [GW]
Data 2014
ø 32,6 €/MWh
Min. -65 €/MWh
Max. 88 €/MWh
Minimum net output of conventional power
plants lies far above minimum residual load
Source: Own illustrations based on eex.com and eex-transparency.com
09.06.15 5
The potential of IGCC poly-generation plants in a changing
energy system
7th international Freiberg/Inner Mongolia Conference on IGCC&XtL Technologies, Alexander Buttler
Gasifier island
Gas cleaning
CCPP
Synthesis unit Electrolysis
unit
Power Production Synfuel Production
100%
0%
Base load demand
(nuclear power phase-
out)
Medium load
demand
Peak load
demand and
energy storage
IGCC allows a very flexible adaption
to the future requirements
09.06.15 6
Water-gas shift membrane reactor
7th international Freiberg/Inner Mongolia Conference on IGCC&XtL Technologies, Alexander Buttler
Theory
Large scale concept
Feed
Membrane tubes
Source: Melin (2004)
Hydrogen flux across the membrane:
With
P…Permeability
δ...Membrane thickness
T…Temperature
pH2…partial pressure
AM…Membrane area
09.06.15 7
Water-gas shift membrane reactor
7th international Freiberg/Inner Mongolia Conference on IGCC&XtL Technologies, Alexander Buttler
Concept and advantages of a flexible WGS-MR-poly-generation plant
WGSGF CCPP
MeOH/SNG
AGR
steam
CO2 to pipeline
HGCUGF CCPP
MeOH/SNG
WGS-MR
steam
CO2 to pipeline
Advantages of MR-concept:
+ Low steam demand for CO-shift
+ Reduced gas temperature cycling
+ variable split of gas streams with
adjusted composition for gas turbine or
synthesis plant
BC…Base Case (Water quench,
Rectisol)
MR…Membrane Reactor (Gas quench,
hot gas clean up)
BC
MR
09.06.15 8
.
.
.
O2
CO2 to pipeline
To synfuel plantH2, CO, CO2; SN=opt.
To gas turbine (N2+H2)
N2 from ASU
Clean gas
steam
H2
H2
H2
H2
H2
H2
Expansion in turbine
Sweep gas
Ret
enta
te
Permeate
Catalytic combustion
Number of WGS-MR for synfuel plant NSYN
Number of WGS-MR for CCPP NCCPP
Water-gas shift membrane reactor
7th international Freiberg/Inner Mongolia Conference on IGCC&XtL Technologies, Alexander Buttler
Detailed poly-generation concept
Splitter for adjustment of optimal gas composition for synthesis plant
𝑛𝑆𝑤𝑒𝑒𝑝
𝑛𝐶=
𝑌∙ 𝑛𝐶,𝐻2+𝑌∙𝑋 ∙𝑛𝐶,𝐻2𝑆𝑁+𝑌∙𝑋 ∙ 𝑛𝐶,𝐶𝑂+ 𝑀−1 ∙𝑛𝐶,𝐻2
With
C…Clean gas
Y…H2-yield
X…CO-conversion
SN…stochiometric number
…….(=H2/CO=2.05)
For MeOH:
For given syngas composition 𝑛𝑆𝑤𝑒𝑒𝑝
𝑛𝐶:
MeOH: 0.43
SNG: 0.30 (𝑆𝑁= 𝑛𝐻2 − 𝑛𝐶𝑂2 𝑛𝐶𝑂 − 𝑛𝐶𝑂2
= 3)
Variable product ratio:
synthesis product/electricity ~ Nsyn/NCCPP
09.06.15 9
Modeling approach and boundary conditions
7th international Freiberg/Inner Mongolia Conference on IGCC&XtL Technologies, Alexander Buttler
Gasifier Island and Gas Cleaning Combined Cycle Power Plant
Membrane Reactor
Ebsilon®Professional
All models validated with industrial
data [Kunze(2012), Buttler(2013)]
09.06.15 10
Main boundary conditions
Gasifier island
• Entrained flow gasifier with syngas cooler
• Fuel Input: 1000 MWth Hard Coal
• Temperature/Pressure: 1400 °C/40 bar
• Carbon Conversion: 98.5 %
• Cryogenic ASU: 0.273 kWh/kg O2
• Rectisol power demand: 0.04-0.06 kWh/kgCO2
• CO2 pressure: 110 bar
Combined Cycle Power Block
• Fuel Gas LHV: 8000 kJ/kg
• Gas turbine: TIT 1300 °C/ 0/0.5-1 load
• 3-pressure HRSG: 130/40/5 bar
Membrane reactor
• Pd/Cu
• H2O/CO 1.6
• H2-yield 94 %
• CO-conversion 98 %
Synthesis plants
• SNG: 3-stage adiabatic fixed bed process 600/450/300 °C, 0/0.5-1 load
• MeOH: LPMEOH isothermal 250 °C, 50 bar
7th international Freiberg/Inner Mongolia Conference on IGCC&XtL Technologies, Alexander Buttler09.06.15 11
37.739.4
42.245.1
52.8
65.461.2
0%
10%
20%
30%
40%
50%
60%
70%
0
100
200
300
400
500
600
700
BCIGCC
BC-SNGIGCC
MRIGCC
MRIGCC-100%SNG-20%*
MRIGCC-50%SNG-60%*
MRSNG
BCSNG
Effi
cien
cy
MW
Net power
SNG production (LHV)
Concept evaluation
7th international Freiberg/Inner Mongolia Conference on IGCC&XtL Technologies, Alexander Buttler
SNG – WGS-MR-poly-generation-process
CO2-sequ.: 91.6% 69.1% >98%
BC…Base Case (Water quench,
Rectisol)
MR…Membrane Reactor (Gas quench,
hot gas clean up)
BC-SNG IGCC…Base Case IGCC
configuration, gas composition adjusted
for SNG-synthesis plant
*values referred to gas turbine load or
synthesis plant load respectively
Electric power must-run of 88 GW (MR SNG)
Reduced SNG-production compared to base case
Poly-generation
09.06.15 12
Concept evaluation
7th international Freiberg/Inner Mongolia Conference on IGCC&XtL Technologies, Alexander Buttler
Methanol – WGS-MR-poly-generation-process
CO2-sequ.: 91.6% 69.1% >98%
BC…Base Case (Water quench,
Rectisol)
MR…Membrane Reactor (Gas quench,
hot gas clean up)
*values referred to gas turbine load or
synthesis plant load respectively37.7
42.244.1
50.4
62.4
58.1
0%
10%
20%
30%
40%
50%
60%
70%
0
100
200
300
400
500
600
700
BCIGCC
MRIGCC
MRIGCC-100%
MeOH-20%*
MRIGCC-50%
MeOH-60%*
MRMeOH
BCMeOH
Effi
cien
cy
MW
Net power
MeOH production (LHV)
Poly-generation
Electric power must-run of 30 GW (MR MeOH)
Slightly increased MeOH-production compared to base case
09.06.15 13
Summary
IGCC concept allows flexible adaption to future requirements in a changing energy system
WGS membrane reactor has the potential to improve the
• Efficiency (about 4 %-points)
• Flexibility (production of several product gas streams with different gas composition)
MeOH is identified as a better option compared to SNG
• Higher sweep gas stream (lower membrane area)
• Lower electric power must-run
• High value follow-up products (MtG, Methanol-to-Propylene)
Outlook:
• Economic evaluation
• Sensitivity analysis of the membrane area
7th international Freiberg/Inner Mongolia Conference on IGCC&XtL Technologies, Alexander Buttler09.06.15 14
The potential of water-gas shift membrane reactors for
CtX and flexible poly-generation processes
Thank you for your attentation!
7th International Freiberg/Inner Mongolia Conference
on IGCC & XtL Technologies, Coal Conversion and Syngas
9 June 2015, Inner Mongolia, China
Dipl.-Ing. Alexander Buttler
Institute for Energy Systems, Technical University of Munich
80
50
76
60
45
30
20
9390
75
27,3
35
50
65
80
0
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120
1990 2000 2010 2020 2030 2040 2050
per
cen
tage
%
PEV relativ zu 2008 THG relativ zu 1990
Bruttostromverbrauch relativ zu 2008 EE-Anteil am BSV
Transformation of the German energy system
7th international Freiberg/Inner Mongolia Conference on IGCC&XtL Technologies, Alexander Buttler
Time schedule of the energy concept of the German government
Goals Energy Concept 2010
Primary energy consumption compared to 2008
Gross electricity consumption compared to 2008
Greenhous gas emissions compared to 1990
Share of renewable energy generation on GEC
09.06.15 16
Actual challenge of volatile renewable feed-in
7th international Freiberg/Inner Mongolia Conference on IGCC&XtL Technologies, Alexander Buttler
Negative electricity prices
1 10
2820
2 1 2 1
15
71
1215
5664 64
0
10
20
30
40
50
60
70
80
2005 2006 2007 2008 2009 2010 2011 2012 2013 2014
Nu
mb
er o
f h
ou
rs [
-]
price = 0 price <0
Source: own calculations based on eex.com
Phelix day-ahead spot market price
-80
-60
-40
-20
0
20
40
60
80
100
0 10 20 30 40 50 60 70 80
Da
y-A
he
ad
Sp
ot m
ark
et p
rice
[€
/MW
h]
Residual load [GW]
Data 2014
ø 32,6 €/MWh
Min. -65 €/MWh
Max. 88 €/MWh
09.06.15 17