MEMBRANE PREPARATION ASEP MUHAMAD SAMSUDIN, S.T.,M.T. MEMBRANE SEPARATION.
Membrane Gas Separation Processes for CO2 Capture from ......RWE Power Membrane Gas Separation...
Transcript of Membrane Gas Separation Processes for CO2 Capture from ......RWE Power Membrane Gas Separation...
RWE Power
Membrane Gas Separation Processes for CO2 Capture
from Coal fired Power Plants
P. M. Follmann, C. Bayer, M. Wessling, T. Melin
RWTH AachenChemical Process Engineering
Some conversations …
Polymer membranes?
“I have heard they corrode …”
How much does it save?
How much can it achieve?
“I mean in %?”
Does it work?
One year of pilot plant operation in Borselen/NL• Water removal• Ash hick-up survived
New pilot plant studies running currently
“How much does it do in %?”
Definition of boundary conditions (I)
Power plant 560 kg/s flue gas
1 bar, 50°C, saturated in water
CO2 13.6%, N2 71.2%, O2 3.2%
Contaminants (SOx, NOx)
Power plant Capture Transport Storage
CO2 requirements?
CO2 concentration
Trace components
How much to be captured?
Definition of boundary conditions (II)
Delivery to pipeline at 130 bar and 30°C
Composition > 95.5 mole-% CO2
max. 4 mole-% of air gases (N2, Ar, O2)
2 scenarios for O2 contentHigh purity (only 100 ppm allowed)
Up to 4 mole-% O2
SOx and NOx (max. 0.5 mole-% in worst case)
Residual water content: not specified
Optimal capture rate: 90% assumed as optimal
Gas separation membranes
Polymeric membranes most suitable
CO2Permeance
CO2/N2Selectivity
CO2/O2Selectivity
CO2/SO2Selectivity
PPO 4.1 20 4.5 1
PEO 1.25 45 15 0.2
SPEEK 0.07 85 28 1
Permeance H2O >> permeance CO2
Mass transfer across membrane:
Pressure ratio across membrane:
ni = Qi AMem (xi pF - yi pP)
Φ = pF / pP
CO2 Removal
Permeate (CO2 rich)
Depleted flue gas
Flue gas
Driving force generation (I)
Feed compression and suction
Fluegas
Depleted flue gas
Compressor Permeate (CO2 rich)
Vacuum unit
Feed compression
Permeate (CO2 rich)
Depleted flue gas
Flue gas
Compressor
Low pressure at the permeate side
Flue gas Permeate (CO2 rich)
Vacuum unit
Depleted flue gas
Sweeping at the permeate side
Depleted flue gas
Flue gas Sweep gas
Permeate (CO2 rich)
Driving force generation (II)
Feed compression Area ↘ , energy ↗ No pressure limitation
Suction Area ↗ , energy ↘ Pressure limitation: ca. 200 mbar
Feed compression + suction Combines advantages of both technologies Most likely concept for driving force generation
Sweeping Only applicable in combination with suction Process steam no adequate sweeping agent
Membrane – A selective splitter
100
0.01
Ideal Highest Enrichment
100
100
0
Nonsense No Enrichment
99.99
100
70
30
Single-stage membrane system (PPO membrane)
0
300
600
900
1200
0.00 0.25 0.50 0.75 1.00
Recovered CO2 fraction of the 1st stage (PPO membrane)
Spec
ific
ener
gy d
eman
d of
the
1st s
tage
[k
J/kg
CO
2 rec
over
ed]
60%
50%40%
30%
3.0 bar
4.0 bar
5.0 bar
2.0 bar
60%
50% 40%
2bar
5 bar
Single-stage membrane system (PPO membrane)
0
300
600
900
1200
0.00 0.25 0.50 0.75 1.00
Recovered CO2 fraction of the 1st stage (PPO membrane)
Spec
ific
ener
gy d
eman
d of
the
1st s
tage
[k
J/kg
CO
2 rec
over
ed]
60%
50%40%
30%
3.0 bar
4.0 bar
5.0 bar
2.0 bar
Single-stage membrane system (PEO membrane)
0
300
600
900
1200
0.00 0.25 0.50 0.75 1.00
Recovered CO2 fraction of the 1st stage (PEO membrane)
Spec
ific
ener
gy d
eman
d of
the
1st s
tage
[k
J/kg
CO
2 rec
over
ed]
70%60% 50%
40%
30%
2.0 bar
3.0 bar
4.0 bar
5.0 bar
Summary single-stage membrane system
Trade-offs CO2 enrichment – CO2 recovery Energy requirement – membrane area
Further enrichment / purification by 2nd membrane stage Single-stage processes only applicable for enrichment
Further treatment to achieve low O2 and SO2 content O2 and SO2 enrich at the low pressure side
Economic framework
Reference power plant
Capital cost Euro/MWhel 20.50
Fuel cost Euro/MWhel 15.20
O&M cost Euro/MWhel 4.60
Membrane process
Compression Euro/kW 500
Vacuum Euro/kW 1000
Membrane Euro/m2 5 - 50
Specific CO2 avoidance cost = COECap - COERefCO2,Ref - CO2,Cap
Two-stage membrane processes without recycling
40-60% CO2
3-5 bar
Flue Gas
95% CO2
To pipeline
ExpanderTo
atmosphere
Expander
CO2 Compressor
0.2 bar
2-4 bar
0.2 bar1.0 bar
1st stage
2nd stage
130 bar
P
P
Two-stage membrane processes without recycling
0
50
100
150
200
0.00 0.25 0.50 0.75 1.00
Recovered CO2 fraction of the 2 stage membrane process without recycling
Spec
ific
CO
2 avo
idan
ce c
osts
of t
he p
roce
ss
[Eur
o/to
n C
O2 av
oide
d]
PPO - PEO PEO - SPEEK
50 Euro/m2
Recovered CO2 fraction
Spec
ific
CO
2av
oida
nce
cost
[Eur
o/to
n C
O2
avoi
ded]
Two-stage membrane processes without recycling
0
50
100
150
200
0.00 0.25 0.50 0.75 1.00
Recovered CO2 fraction of the 2 stage membrane process without recycling
Spec
ific
CO
2 avo
idan
ce c
osts
of t
he p
roce
ss
[Eur
o/to
n C
O2 a
void
ed]
PPO - PEO PEO - SPEEK
5 Euro/m2
Recovered CO2 fraction
Spec
ific
CO
2av
oida
nce
cost
[Eur
o/to
n C
O2
avoi
ded]
Two-stage membrane processes with recycling
40-60% CO2
3-5 bar
Flue Gas
95% CO2
To pipeline
ExpanderTo
atmosphere
Expander
CO2 Compressor
0.2 bar
2-4 bar
0.2 bar1.0 bar
1st stage
2nd stage
130 bar
Compressor
Recycle stream
2-4 bar
P
P
Two-stage membrane processes with recycling
0
50
100
150
200
0.00 0.25 0.50 0.75 1.00
Recovered CO2 fraction of the two stage membrane process with recycling
Spe
cific
CO
2 avo
idan
ce c
osts
[Eur
o/to
n]
PEO - SPEEK
PPO - PEO
50 Euro/m2
Recovered CO2 fraction0.00 0.25 0.50 0.75 1.00
0
50
100
150
200
Spec
ific
CO
2av
oida
nce
cost
[Eur
o/to
n C
O2
avoi
ded]
Two-stage membrane processes with recycling
0
50
100
150
200
0.00 0.25 0.50 0.75 1.00
Recovered CO2 fraction of the 2 stage membrane process with recycling
Spec
ific
CO
2 avo
idan
ce c
osts
of t
he p
roce
ss
[Eur
o/to
n C
O2 a
void
ed]
PEO - SPEEK
PPO - PEO
5 Euro/m2
Recovered CO2 fraction0.00 0.25 0.50 0.75 1.00
0
50
100
150
200
Spec
ific
CO
2av
oida
nce
cost
[Eur
o/to
n C
O2
avoi
ded]
Summary and conclusions
Chemical durability of polymeric materials proven during one year piloting
Two stage membrane processes required + 90% CO2 recovery in conjunction with 95% purity
+ Simple integration in power plant process
+ Competitive economics compared to absorption process
+ Scalable modular membrane area
- CO2 product does not comply with strict purity requirements
- Specific energy requirement higher than chemical absorption
- Membrane cost have significant impact on process economics
RWE Power
Thank you very much for your attention
This study is part of the NanoGLOWA project (NMP3-CT-2007-026735), which has been financially supported by the EU Commission within the thematic priority NMP of the Sixth Framework Program.
Single-stage membrane system (PEO membrane)
0
300
600
900
1200
0.00 0.25 0.50 0.75 1.00
Recovered CO2 fraction of the 1st stage (PEO membrane)
Spec
ific
ener
gy d
eman
d of
the
1st s
tage
[k
J/kg
CO
2 rec
over
ed]
70%60% 50%
40%
30%
2.0 bar
3.0 bar
4.0 bar
5.0 bar
Two-stage membrane processes with recycling
Two-stage membrane processes without recycling
0
1000
2000
3000
4000
0.00 0.25 0.50 0.75 1.00
Recovered CO2 fraction of the 2 stage membrane process without recycling
Spec
ific
ener
gy d
eman
d of
the
proc
ess
[kJ/
kg C
O2 r
ecov
ered
]
PPO - PEO PEO - SPEEK
Recovered CO2 fraction
Two-stage membrane processes with recycling
0
1000
2000
3000
4000
0.00 0.25 0.50 0.75 1.00
Recovered CO2 fraction of the 2 stage membrane process with recycling
Spec
ific
ener
gy d
eman
d of
the
proc
ess
[kJ/
kg C
O2 r
ecov
ered
]
PPO - PEO PEO - SPEEK
Recovered CO2 fraction0.00 0.25 0.50 0.75 1.00
Two-stage membrane processes with recycle
90% CO2 recovery: PPO / PEO system
Feed pres.1st/2nd stage
Energy[kJ/kg]
Area [105 m2]
O2[%]
SO2[ppm]
3 bar / 4 bar 1910 7 1.8 510
4 bar / 4bar 1940 5 1.8 510
Feed pres.1st/2nd stage
Energy[kJ/kg]
Area [106 m2]
O2[%]
SO2[ppm]
2 bar / 4 bar 1350 8 1.2 520
3 bar / 4bar 1400 5.1 1.2 520
90% CO2 recovery: PEO / SPEEK system