carbonate looping experiments in 1 mwth scale using a cfb
TRANSCRIPT
Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
Petersenstrasse 3064287 Darmstadt / GermanyPhone: +49 6151 16 2191www.est.tu-darmstadt.de
Carbonate looping experiments in 1 MWth scale using a CFB calciner fired with coal and oxygen-enriched air
Jochen Ströhle
2nd International Workshop onOxyfuel FBC Technology28-29 June 2012 at University of Stuttgart
Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
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Outline
Carbonate looping process
1 MWth pilot plant at TU Darmstadt
Results of experiments with propane-fired calciner
with coal-fired calciner
Conclusions
Further work
Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
Carbonate Looping Process
Retrofit of existing power plants is feasible. Repowering: Electrical power of total plant increases by ~80 %. Steam parameters of 600 / 620 °C in the CL unit are feasible Efficiency decreases by < 3 % units (without CO2 compression) CO2 capture of ~88 % CO2 avoidance costs of ~20 €/t CO2
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Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
Sketch of a Carbonate Looping Unit
Carbonate looping unit of 1050 MWel hard coal fired plant One of two parallel flue
gas cleaning trains
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Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
Scheme of 1 MWth CL Pilot Plant
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Filter Cyc
lone
Cal
cine
r, 90
0 °C
CFB
600
Coa
l Com
bust
or
HeatExchanger
Sta
ck
Car
bona
tor,
650°
CFan
Fan
Induced Draft Fan
Fan
Coal
Ash
Flue Gas
Decarbonized Flue Gas
Fly Ash
CaCO3
CaO
Option: Air
Ash
CO
2
N2
OptionC
yclo
ne
CaCO3(Makeup)
Coal
CFB
400
CO
2
O2
Filter
FGD
HeatExchanger
Sta
ck
Induced Draft Fan
CO2
Fly Ash
Filter
Preheating Preheating
Steam
Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
3D View of Laboratory
Erected in 2009 20 m high
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Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
Layout of Coupled CFB Reactors
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CarbonatorCFB600
CalcinerCFB400
Inner diameter 0.6 m 0.4 mOuter diameter 1.3 m 1.0 mHeight 8.66 m 11.35 mCal
cine
r
Car
bona
tor
Calciner
Carbonator
Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
CL Experiments in 1 MWth Plant
July 2011: CO2 capture with propane-fired calciner 5 weeks of 3 shift operation 72 hours of continuous CO2 Capture, Calciner fired with propane
Jan 2012: CO2 capture with coal/propane-fired calciner (Campaign Propane) 19 days of 3 shift operation 121 hours of CO2 capture Calciner mainly propane-fired
Feb 2012: CO2 capture with coal-fired calciner (Campaign Coal) 5 days of 3 shift operation 30 hours of CO2 capture El Cerrejón coal
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Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
Campaign Propane
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CO2 absorption: 60 – 88 %Gas velocity: 2.3 – 3.3 m/sAverage makeup: 59 kg/h (CaCO3)Particle size: 100 – 300 µm
Gas velocity: 3 – 4 m/sPower: 420 – 500 kWthO2 in: 35 – 40 % vol.
56 % vol. O2
Air
Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
Campaign Propane
Period of 12 hours stable operation
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CO2 absorptioncarbonator
CO2 capture total
Carbonator Calciner
O2 in
CO2 out
Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
Campaign Coal
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CO2 absorption: 58 – 88 %Gas velocity: 2.3 – 2.6 m/sAverage makeup: 8 kg/h (CaCO3)Particle size: 100 – 300 µm
Gas vel.: 3.2 – 3.8 m/sPower: 550 – 800 kWthO2 in: 43 – 50 % vol.
51-57 % vol. O2
Air
Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
Campaign Coal
Period of 20 hours stable operation
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Carbonator Calciner
CO2 absorption carbonator
CO2 capture total O2 in
CO2 out
Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
Effect of CO2 equilibrium and chemical kinetics in carbonator
Campaign Coal
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equilibrium CO2 conc.
CO2 conc. at exit
Start CO2
1 2 3 4 1. no CO2 addition
2. CO2 absorption limited by equilibrium
3. CO2 absorption limited by kinetics (~640 °C)
4. CO2 absorption limited by kinetics (~610 °C)
Start cooling
Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
Operation of Carbonator
a) CO2 absorption limited by equilibrium: Temperature increases CO2 equilibrium concentration increases CO2 absorption decreases Temperature decreases Stable operation
b) CO2 absorption limited by chemical kinetics: Temperature increases CO2 absorption increases Temperature increases further CO2 absorption finally limited by equilibrium or availability of CaO Unstable operation
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2,1.432 1011 19130
E.H. Baker, J. Chemical Society, 1962
Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
Conclusions
1 MWth CL pilot plant in continuous operation
>200 hours of CO2 capture
Propane-/Coal-fired calciner
~50 % vol. O2 enrichment in calciner
>80 % CO2 absorption in the carbonator
>90 % total CO2 capture (carbonate + oxyfuel fired calciner)
CO2 absorption in carbonator strongly dependent on temperature either limited by equilibrium (stable operation) or by chemical kinetics (unstable operation)
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Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
Further Work
Test with real flue gas from coal-fired furnace (1 MWth)
Test at real oxyfuel conditions in calciner (O2/CO2/steam mixture)
Optimization of operating conditions
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Swirl burner
Water-cooled membrane walls
Water-cooled tube bundles
Energy Systemsand TechnologyProf. Dr.-Ing. B. Epple
Acknowledgements
COORETEC Project “LISA” - Limestone based Absorption of CO2
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