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12th Meeting of the International PCC Network – Regina, Canada 29 Sep – 1 Oct 2009
Evaluation of Process Improvements in Pilot Scale – Activities Under the EU CESAR Project Jacob Nygaard Knudsen, DONG Energy
CESAR Project Consortium CESAR: CO2 Enhanced Separation And Recovery 3-year EU project (2008 – 2011) in the 7th Framework Programme Aim: To reduce the cost of CO2 post-combustion capture
R&D
Oil & Gas
IFP (FR) STATOILHYDRO (NO) TNO (NL) GDF (FR) SINTEF (NO) NTNU (NO) POLYMEN (FR) CNRS (FR) U. KAISERSLAUTERN (DE)
Power Companies
Manufacturers
DONG Energy (DK) VATTENFALL (SE/DK) E.ON (DE/UK) ELECTRABEL (BE) RWE (DE/UK) PPC (GR) POWERGEN (UK)
ALSTOM POWER (SE) DOOSAN BABCOCK (UK) SIEMENS (DE) BASF (DE)
Doc. info
Coordinator: TNO
2
Outline CESAR Project
WP3 Solvent process validation Qualification of solvents Solvent process validation in Esbjerg pilot plant Environmental impact
WP1 Advanced separation processes Solvent selection Novel solvents High flux membrane contactors
Doc. info
WP2 Process modeling & Integration Development of process models Integration studies European benchmark task force
3
CESAR Objectives of Pilot Plant Testing in Esbjerg Evaluate the potential of advanced absorption/desorption process configurations in pilot-scale Determine the performance of novel solvents in realistic operation conditions for future full-scale application in coal-fired power plants Measure energy requirement and temperature levels for regeneration of the novel solvents
Doc. info
Monitor actual solvent degradation, losses and by-products, corrosion, fouling and emissions for novel solvents
4
Esbjerg Power Station (ESV) Esbjerg Power Station 400 MWe pulverized bituminous coal High dust SCR deNOx plant 3 zones cold-sided ESP
Doc. info
Wet limestone FGD (saleable gypsum)
5
The CO2 Capture Pilot Plant at Esbjerg Power Plant
Pilot Plant Specifications Operates on a slip stream of flue gas taken directly after the wet FGD Flue gas flow: 5000 Nm3/h (0.5% of 400 MWe) CO2 capture capacity: 1000 kg/h
Doc. info
Cleaning efficiency: 90%
6
Esbjerg Pilot Plant Flow Diagram Bubble cap polisher
Treated flue gas
Cooling water circuit
Fresh water Wash section
Absorber inter-cooling
Revamping of absorber with structured packing
CO2 Out
Expansion of cross flow heat exchanger
Condensate
Steam Reboiler
ABSORBER
MEA/MEA heat exchanger
STRIPPER
Flue gas from power plant Lean MEA Rich MEA
Doc. info
Mechanical filters
7
Installation of vapour recompression
CESAR Pilot Plant Modifications: Inter-cooler & Flash Vessel
Doc. info Doc. info
Absorber inter-cooler skid
Flash vessel for vapour recompression
8
Pilot Plant Operation History and Outlook Four test campaigns have been conducted during CASTOR and three more are scheduled for the CESAR project: 1000 hours using standard solvent ”30%-wt. MEA” (Jan – Mar 2006) 1000 hours using standard solvent ”30%-wt. MEA” (Dec 2006 – Feb 2007)
CASTOR
1000 hours using novel solvent ”CASTOR 1” (April – June 2007) 1000 hours using novel solvent ”CASTOR 2” (Sep – Dec 2007) >1000 hours using standard solvent ”30%-wt. MEA” (Mar 2009 – July 2009) in modified pilot plant >1000 hours using novel solvent ”CESAR 1” (Oct 2009 – Dec 2009) in modified pilot plant
Doc. info
>1000 hours using novel solvent ”CESAR 2” (Feb 2010 – Jun 2010) in modified pilot plant
9
Outline of CESAR MEA Test Campaign Test 1 – Parameter variation a) b) c) d) e)
Optimisation of solvent flow rate (at 90% capture) Effect of absorber inter-cooling Effect of vapour re-compression Variation of CO2 capture percentage Variation of stripper pressure
Test 2 – 500 hours of continuous operation - Operation at ”optimised” conditions and achieving 90% CO2 capture (on average) - Quantification of solvent consumption and degradation - Characterisation of corrosion behaviour
Doc. info
Test 3 – Miscellaneous tests - Transient test & load following capability - Emission measurements - Etc.
10
Optimisation of Absorber L/G with Improved Cross Flow HX Specific steam consumption at stripper pressure 0.85 barg, flue gas flow ≈5000 Nm3/h and ≈90 % CO2 recovery Steam consump.
CO2 recovery
4,0
100
3,8
90
3,6
80
T = 4.0-4.3ºC 3,4
70
3,2
60
3,0
50
Doc. info
2,0
2,5
3,0 3,5 Absorber L/G ratio (kg/kg)
11
4,0
CO2 recovery (%)
Steam consumption (GJ/ton CO2)
CASTOR: T = 7.1-8.0ºC
Effect of Process Modifications: Absorber Inter-cooling (1/2) Flue gas flow ≈5000 Nm3/h, L/G ≈3 kg/kg, Stripper pressure =0,85 barg, CO2 capture ≈90% 45,0
37,5
30,0
Steam consump.
24,9
Steam consumption (GJ/ton CO2)
75
Abs. temperature (oC)
65
55
45
35
25 0
Doc. info
Flue gas 48ºC
4
8
12
16
20
Packing height (m)
Solvent 40ºC
12
CO2 capture
4,0
100
3,8
90
3,6
80
3,4
70
3,2
60
3,0
50 20
30
40
50
Inter-cooler temperature (oC)
60
CO2 recovery (%)
58,1
Effect of Process Modifications: Absorber Inter-cooling (2/2) Flue gas flow ≈5000 Nm3/h, L/G ≈3 kg/kg, Stripper pressure =0,85 barg, CO2 capture ≈90% Rich loading
Temp. rich …
0,45
45
0,40
40 20
30 40 50 Inter-cooler temperature (oC)
60
Absorber pressure drop (mm H2O)
50
0,50
Temperature rich MEA (oC)
Rich loading (mol CO2/mol MEA)
55
0,55
Doc. info
300
60
0,60
280
260
240
220
200 20
13
30 40 50 o Inter-cooler temperature ( C)
60
Effect of Process Modifications: Lean Vapour Re-compression Flue gas flow ≈5000 Nm3/h, L/G ≈3 kg/kg, Stripper pressure =0,85 barg, CO2 capture ≈90%, no inter-cooling Steam
Power 50
3,8 40 3,6 30
3,4 3,2
20
3,0 10 2,8 2,6
0 0,0
0,2
0,4
0,6
Doc. info
Flash pressure (barg)
14
0,8
1,0
Increased power consump. (kWh/ton CO2)
Steam consumption (GJ/ton CO2)
4,0
CESAR MEA Test: 500 Hours of Continuous Operation L/G ≈3 kg/kg ,stripper pressure 0.85 barg with inter-cooling and vapour re-compression Flue gas flow
Steam consump.
CO2 recovery 100
5.000
80
4.000 60 3.000 40 2.000 20
1.000
0
0 20‐05‐09
CO2 recovery (%)
Flue gas flow & Steam consumption (Nm3/h & MJ/ton CO2)
6.000
25‐05‐09
30‐05‐09
04‐06‐09
09‐06‐09
14‐06‐09
Doc. info
Average steam consumption: 3.07 GJ/ton CO2 (+ 24 kWh/ton CO2) Average CO2 capture: 90 % (Result from CASTOR: 3.7 GJ/ton CO2)
15
Influence of Reboiler Steam Input Flue gas flow ≈5000 Nm3/h, L/G ≈3 kg/kg ,stripper pressure 0.85 barg with inter-cooling and vapour re-compression
100
3,3
90
3,1
80
2,9
70
2,7
60
2,5 1100
Doc. info
CO2 recovery
1200
1300 1400 1500 Reboiler steam input (kg/h)
16
1600
50 1700
CO2 recovery (%)
Steam consumption (GJ/ton CO2)
Steam consump. 3,5
Conclusions Several process upgrades have been introduced at the Esbjerg CO2 capture pilot plant . A benchmark campaign using 30% MEA has among others indicated that: Reducing the T of the solvent cross flow heat exchanger from ≈7.5 to 4.5ºC leads only to minor saving in reboiler steam consumption (≈ 0.1 GJ/ton CO2), however, it allows for lower reboiler temperatures (i.e. higher L/G) at reduced penalty Inter-cooling seems to have only marginal effect on reboiler steam consumption with MEA, however, as a co-benefit the absorber P is reduced Vapour re-compression may lower reboiler steam consumption substantially (3.6 to 2.8 GJ/ton) on account on increased power consumption. A full cost benefit analysis is required to determine the true benefits Acknowledgements
Doc. info
The pilot plant in Esbjerg is sponsored by the CESAR partners, the European Commission through the CESAR project, and the CLEO project sponsors: Aker Clean Carbon, EDF, EnBW, Enel & Hitachi Power Europe
17
Evaluation of Process Improvements in Pilot Scale – Activities Under the EU CESAR Project Jacob Nygaard Knudsen, DONG Energy
CESAR Project Consortium CESAR: CO2 Enhanced Separation And Recovery 3-year EU project (2008 – 2011) in the 7th Framework Programme Aim: To reduce the cost of CO2 post-combustion capture
R&D
Oil & Gas
IFP (FR) STATOILHYDRO (NO) TNO (NL) GDF (FR) SINTEF (NO) NTNU (NO) POLYMEN (FR) CNRS (FR) U. KAISERSLAUTERN (DE)
Power Companies
Manufacturers
DONG Energy (DK) VATTENFALL (SE/DK) E.ON (DE/UK) ELECTRABEL (BE) RWE (DE/UK) PPC (GR) POWERGEN (UK)
ALSTOM POWER (SE) DOOSAN BABCOCK (UK) SIEMENS (DE) BASF (DE)
Doc. info
Coordinator: TNO
2
Outline CESAR Project
WP3 Solvent process validation Qualification of solvents Solvent process validation in Esbjerg pilot plant Environmental impact
WP1 Advanced separation processes Solvent selection Novel solvents High flux membrane contactors
Doc. info
WP2 Process modeling & Integration Development of process models Integration studies European benchmark task force
3
CESAR Objectives of Pilot Plant Testing in Esbjerg Evaluate the potential of advanced absorption/desorption process configurations in pilot-scale Determine the performance of novel solvents in realistic operation conditions for future full-scale application in coal-fired power plants Measure energy requirement and temperature levels for regeneration of the novel solvents
Doc. info
Monitor actual solvent degradation, losses and by-products, corrosion, fouling and emissions for novel solvents
4
Esbjerg Power Station (ESV) Esbjerg Power Station 400 MWe pulverized bituminous coal High dust SCR deNOx plant 3 zones cold-sided ESP
Doc. info
Wet limestone FGD (saleable gypsum)
5
The CO2 Capture Pilot Plant at Esbjerg Power Plant
Pilot Plant Specifications Operates on a slip stream of flue gas taken directly after the wet FGD Flue gas flow: 5000 Nm3/h (0.5% of 400 MWe) CO2 capture capacity: 1000 kg/h
Doc. info
Cleaning efficiency: 90%
6
Esbjerg Pilot Plant Flow Diagram Bubble cap polisher
Treated flue gas
Cooling water circuit
Fresh water Wash section
Absorber inter-cooling
Revamping of absorber with structured packing
CO2 Out
Expansion of cross flow heat exchanger
Condensate
Steam Reboiler
ABSORBER
MEA/MEA heat exchanger
STRIPPER
Flue gas from power plant Lean MEA Rich MEA
Doc. info
Mechanical filters
7
Installation of vapour recompression
CESAR Pilot Plant Modifications: Inter-cooler & Flash Vessel
Doc. info Doc. info
Absorber inter-cooler skid
Flash vessel for vapour recompression
8
Pilot Plant Operation History and Outlook Four test campaigns have been conducted during CASTOR and three more are scheduled for the CESAR project: 1000 hours using standard solvent ”30%-wt. MEA” (Jan – Mar 2006) 1000 hours using standard solvent ”30%-wt. MEA” (Dec 2006 – Feb 2007)
CASTOR
1000 hours using novel solvent ”CASTOR 1” (April – June 2007) 1000 hours using novel solvent ”CASTOR 2” (Sep – Dec 2007) >1000 hours using standard solvent ”30%-wt. MEA” (Mar 2009 – July 2009) in modified pilot plant >1000 hours using novel solvent ”CESAR 1” (Oct 2009 – Dec 2009) in modified pilot plant
Doc. info
>1000 hours using novel solvent ”CESAR 2” (Feb 2010 – Jun 2010) in modified pilot plant
9
Outline of CESAR MEA Test Campaign Test 1 – Parameter variation a) b) c) d) e)
Optimisation of solvent flow rate (at 90% capture) Effect of absorber inter-cooling Effect of vapour re-compression Variation of CO2 capture percentage Variation of stripper pressure
Test 2 – 500 hours of continuous operation - Operation at ”optimised” conditions and achieving 90% CO2 capture (on average) - Quantification of solvent consumption and degradation - Characterisation of corrosion behaviour
Doc. info
Test 3 – Miscellaneous tests - Transient test & load following capability - Emission measurements - Etc.
10
Optimisation of Absorber L/G with Improved Cross Flow HX Specific steam consumption at stripper pressure 0.85 barg, flue gas flow ≈5000 Nm3/h and ≈90 % CO2 recovery Steam consump.
CO2 recovery
4,0
100
3,8
90
3,6
80
T = 4.0-4.3ºC 3,4
70
3,2
60
3,0
50
Doc. info
2,0
2,5
3,0 3,5 Absorber L/G ratio (kg/kg)
11
4,0
CO2 recovery (%)
Steam consumption (GJ/ton CO2)
CASTOR: T = 7.1-8.0ºC
Effect of Process Modifications: Absorber Inter-cooling (1/2) Flue gas flow ≈5000 Nm3/h, L/G ≈3 kg/kg, Stripper pressure =0,85 barg, CO2 capture ≈90% 45,0
37,5
30,0
Steam consump.
24,9
Steam consumption (GJ/ton CO2)
75
Abs. temperature (oC)
65
55
45
35
25 0
Doc. info
Flue gas 48ºC
4
8
12
16
20
Packing height (m)
Solvent 40ºC
12
CO2 capture
4,0
100
3,8
90
3,6
80
3,4
70
3,2
60
3,0
50 20
30
40
50
Inter-cooler temperature (oC)
60
CO2 recovery (%)
58,1
Effect of Process Modifications: Absorber Inter-cooling (2/2) Flue gas flow ≈5000 Nm3/h, L/G ≈3 kg/kg, Stripper pressure =0,85 barg, CO2 capture ≈90% Rich loading
Temp. rich …
0,45
45
0,40
40 20
30 40 50 Inter-cooler temperature (oC)
60
Absorber pressure drop (mm H2O)
50
0,50
Temperature rich MEA (oC)
Rich loading (mol CO2/mol MEA)
55
0,55
Doc. info
300
60
0,60
280
260
240
220
200 20
13
30 40 50 o Inter-cooler temperature ( C)
60
Effect of Process Modifications: Lean Vapour Re-compression Flue gas flow ≈5000 Nm3/h, L/G ≈3 kg/kg, Stripper pressure =0,85 barg, CO2 capture ≈90%, no inter-cooling Steam
Power 50
3,8 40 3,6 30
3,4 3,2
20
3,0 10 2,8 2,6
0 0,0
0,2
0,4
0,6
Doc. info
Flash pressure (barg)
14
0,8
1,0
Increased power consump. (kWh/ton CO2)
Steam consumption (GJ/ton CO2)
4,0
CESAR MEA Test: 500 Hours of Continuous Operation L/G ≈3 kg/kg ,stripper pressure 0.85 barg with inter-cooling and vapour re-compression Flue gas flow
Steam consump.
CO2 recovery 100
5.000
80
4.000 60 3.000 40 2.000 20
1.000
0
0 20‐05‐09
CO2 recovery (%)
Flue gas flow & Steam consumption (Nm3/h & MJ/ton CO2)
6.000
25‐05‐09
30‐05‐09
04‐06‐09
09‐06‐09
14‐06‐09
Doc. info
Average steam consumption: 3.07 GJ/ton CO2 (+ 24 kWh/ton CO2) Average CO2 capture: 90 % (Result from CASTOR: 3.7 GJ/ton CO2)
15
Influence of Reboiler Steam Input Flue gas flow ≈5000 Nm3/h, L/G ≈3 kg/kg ,stripper pressure 0.85 barg with inter-cooling and vapour re-compression
100
3,3
90
3,1
80
2,9
70
2,7
60
2,5 1100
Doc. info
CO2 recovery
1200
1300 1400 1500 Reboiler steam input (kg/h)
16
1600
50 1700
CO2 recovery (%)
Steam consumption (GJ/ton CO2)
Steam consump. 3,5
Conclusions Several process upgrades have been introduced at the Esbjerg CO2 capture pilot plant . A benchmark campaign using 30% MEA has among others indicated that: Reducing the T of the solvent cross flow heat exchanger from ≈7.5 to 4.5ºC leads only to minor saving in reboiler steam consumption (≈ 0.1 GJ/ton CO2), however, it allows for lower reboiler temperatures (i.e. higher L/G) at reduced penalty Inter-cooling seems to have only marginal effect on reboiler steam consumption with MEA, however, as a co-benefit the absorber P is reduced Vapour re-compression may lower reboiler steam consumption substantially (3.6 to 2.8 GJ/ton) on account on increased power consumption. A full cost benefit analysis is required to determine the true benefits Acknowledgements
Doc. info
The pilot plant in Esbjerg is sponsored by the CESAR partners, the European Commission through the CESAR project, and the CLEO project sponsors: Aker Clean Carbon, EDF, EnBW, Enel & Hitachi Power Europe
17
