post combustion co2 capture scale up study pdfs... · capture process modeled using bryan research...

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PROJECT MANAGER POWER GENERATION SERVICES TOM GUENTHER

POST COMBUSTION CO2 CAPTURE SCALE UP STUDY

• Retained by IEA Environmental Projects Ltd.

• In order for CCS to impact climate change, full scale capture is necessary.

• Identify at a high level the technical risks, gaps, and challenges associated with full scale implementation of post-combustion CO2 capture

• Focus on currently available technologies demonstrated at a smaller scale

• Include both pulverized coal and natural gas fired combined cycle

• Study completed in 2012

PURPOSE OF STUDY

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Principle Authors - Black & Veatch • Anthony Black – Process Engineer • Tom Guenther – Project Manager • Dan McCartney – Senior Process Engineer • Scott Olson – Senior Consultant • Brian Reinhart – Mechanical Engineer/Study Manager

Reviewers: • Mike Haines – IEAGHG • Prachi Singh – IEAGHG • Tore Amundsen – CO2 Technology Centre Mongstad • Max Ball – Saskpower • Nick Booth – EON • Rosa Domenicini – Foster Wheeler • Frank Geuzebroeck – Shell Amsterdam • Robin Irons – EON • Mohammad Adu Zahra - Institute of Masadar

AUTHORS

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• Select two modern full-scale power plant designs: • Supercritical pulverized coal (SCPC) • Natural gas combined cycle (NGCC)

• Plant performance and equipment size without CO2 capture

• Plant performance and equipment size with improved amine-based post-combustion carbon capture

• Identify any risks, gaps, and challenges associated with the full scale designs (power and capture)

APPROACH

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• Case 1 – 900 MW Gross SCPC without CO2 capture

• Case 2 – “TBD” MW SCPC with CO2 capture

• Case 3 – 810 MW Gross NGCC without CO2 capture

• Case 4 – “TBD” MW NGCC with CO2 capture

DESIGN CASES

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Fuel quantity held constant from Case 1-2 and 3-4

DESIGN BASIS

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DESIGN CASE 1 SCPC WITHOUT CAPTURE

DESIGN CASE 2 SCPC WITH CO2 CAPTURE

DESIGN CASE 3 NGCC WITHOUT CAPTURE

DESIGN CASE 4 NGCC WITH CO2 CAPTURE

CO2 Capture, % of Gross N/A 90 N/A 90

Technology Description Supercritical pulverized coal Rankine cycle

with 1 two-pass tangential or wall-fired boiler and 1 reheat condensing steam turbine.

Natural gas combined cycle with 2x G-Class gas turbines, 2x three-pressure heat recovery steam generators, and 1x reheat condensing

steam turbine.

Nominal Gross Output, MW 900 TBD(1) 810 TBD(1)

Unit Output Frequency, Hz 60 60 60 60

Fuel Australian Low-Sulfur Same as Case 1 Natural Gas Same as Case 3

Fuel Quantity Note 1 Same as Case 1 Note 1 Same as Case 3 Throttle Conditions (MS temperature, HRH temperature, MS pressure) ° C / ° C / bar(a) (° F / ° F / psia)

582 / 582 / 254.4 (1,080 / 1,080 / 3,690)

565.6 / 565.6 / 124.1 (1,050 / 1,050 / 1,800)

Supplemental Firing N/A N/A No No

Heat Rejection Wet mechanical draft cooling tower Auxiliary Boiler During Normal Operations No No No No

Air Quality Control Systems Selective Catalytic Reduction, PAC Injection, Fabric Filter, Wet Flue Gas Desulfurization

Dry Low NOx Combustion, Selective Catalytic Reduction, Oxidation

Catalyst CO2 Export Pressure, bar(a) (psia)

N/A 110 (1,600)

N/A 110 (1,600)

Notes: (1) Fuel quantity to be determined as part of the study. As a basis of the design, CO2 capture case will use the same amount of fuel as the non-capture case.

• Power processes modeled using Thermoflow, Inc. STEAMPRO, STEAM MASTER, GT PRO, GT MASTER, and Black & Veatch proprietary software

• Capture process modeled using Bryan Research & Engineering, Inc. ProMax 3.2 software

• Capture process simulation data based on MEA and adjusted to reflect typical enhanced amines, primarily solvent regeneration duty

PROCESS SIMULATION

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CASE 2 – SCPC WITH CO2 CAPTURE

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CASE 4 – NGCC WITH CO2 CAPTURE

PERFORMANCE SUMMARY - SCPC

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UNIT CASE 1 CASE 2

Reference Case Description Supercritical Pulverized Coal Rankine Cycle

CO2 Capture % None 90

ELECTRICAL OUTPUT

Total Gross Output MW 900.1 756.6

Auxiliary Electric Load

Power Block MW 35.5 35.1

Flue Gas Fans MW 17.2 44.0

Air Quality Systems MW 5.8 8.5

CO2 Capture MW N/A 5.2

CO2 Compression MW N/A 75.0

Total Auxiliary Electric Load MW 58.5 167.8

Net Plant Output MW 841.6 588.8

Energy Penalty (Net output) % N/A -30.0

Energy Penalty (Net output reduction per tonne-CO2 to pipeline)

MW/(t-CO2 captured) N/A 0.40

ELECTRICAL PRODUCTION EFFICIENCY

Net Plant Heat Rate (NCV) kJ/kWh 8,912 12,738

Net Plant Thermal Efficiency (NCV) % 40.4 28.3

CO2 EMISSIONS

CO2 Captured t/h N/A 629

CO2 to Atmosphere t/h 702 73 CO2 to Atmosphere kg/MWh-net 834 124

PERFORMANCE SUMMARY - NGCC

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UNIT CASE 3 CASE 4

Reference Case Description 2-on-1 G-Class Gas Turbine Combined Cycle

CO2 Capture % None 90

ELECTRICAL OUTPUT

Gross Output

STG MW 280.4 223.7

Gas Turbine Generators (total) MW 529.5 529.5

Total Gross Output MW 809.9 753.2

Auxiliary Electric Load

Power Block MW 19.6 22.1

Flue Gas Fans MW N/A 26.1

CO2 Capture MW N/A 3.6

CO2 Compression MW N/A 25.5

Total Auxiliary Electric Load MW 19.6 77.3

Net Plant Output MW 790.3 675.9

Energy Penalty (Net output) % N/A -14.5

Energy Penalty (Net output reduction per tonne-CO2 to pipeline)

MW/(t-CO2 captured) N/A 0.46

ELECTRICAL PRODUCTION EFFICIENCY

Net Plant Heat Rate (NCV) kJ/kWh 6,208 7,259

Net Plant Thermal Efficiency (NCV) % 58.0 49.6

CO2 EMISSIONS

CO2 Captured t/h N/A 250

CO2 to Atmosphere t/h 276 28

CO2 to Atmosphere kg/MWh-net 349 41

KEY CO2 CAPTURE EQUIPMENT OVERVIEW

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FEATURE SCPC NGCC

Number of Absorbers 1 x 6 sections 1 x 6 sections

Absorber Cross-Sectional Area, m2 317 317

Absorber Height, m 28 28

Number of Strippers 2 1

Stripper Diameter, m 7.2 7.0

Stripper Height, m 23 23

Number of Stripper Reboilers 8 4

Number of Rich/Lean Exchangers 3 2

Number of Stripper Overhead Coolers 5 2

Number of Lean Amine Coolers 5 1

Number of CO2 Compressor Trains 2 2

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CASE 2 – SCPC LAYOUT

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CASE 4 – NGCC LAYOUT

1. Steam Generator • Stiffening of boiler/HRSG/ductwork may be

needed but not a significant challenge

2. Fans • 4 series/parallel axial fans for SCPC case (11,000

kW each) • 2 axial fans for NGCC case (1 per HRSG) (13,000

kW each) 3. Flue Gas Cleanup (SCPC)

• Wet FGD commonplace • Additional polishing in SCPC case to reduce amine

degradation by SO2

TECHNICAL RISKS, GAPS, AND CHALLENGES

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4. Steam Extraction • Significant LP (4.5 bar[a]) Steam Required • >30% of steam flow for SCPC • LP turbine design • Steam turbine OEMs able to modify designs • Issues at reduced load (sliding pressure) • Opportunities for optimization

TECHNICAL RISKS, GAPS, AND CHALLENGES

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5. Cooling • Cooling load increased 20

percent for SCPC • Cooling load increased 40

percent for NGCC • No technical risk but maybe

site specific

TECHNICAL RISKS, GAPS, AND CHALLENGES

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6. Absorber • Largest technical challenge • Assumed single rectangular concrete structure

with multiple sections • 7-8 meter span limit for support of internals • Difficult, but similar construction methods to large

stack or cooling tower design • Constructed at site

7. Stripper • Large, but technology considered commonplace • Multiple strippers feasible • Transported vs. construction at site (site specific)

TECHNICAL RISKS, GAPS, AND CHALLENGES

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8. Compression • Assumed 3 stages of compression, single shaft,

motor driven • Could use integrally geared or add pump • No significant risk at this scale • Potentially use waste heat for optimization, 5 MW

available in SCPC case 9. CO2 Drying

• Assumed/prefer solid bed adsorbent • Technology considered commonplace

TECHNICAL RISKS, GAPS, AND CHALLENGES

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10. Environmental and Safety • Regulations still evolving

• CO2 handling and storage • Solvent emissions,

nitramines, nitrosamines • Solvent wastes

• Quantity of emissions increases with scale

• Hazards associated with concentrated CO2

TECHNICAL RISKS, GAPS, AND CHALLENGES

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No technical deal breakers identified….full scale capture appears achievable

Recommended areas of development for full-scale capture: • Modified steam turbine designs • Optimize steam extraction • Absorber construction • Reuse of compression heat • Environmental impacts • Safety

CONCLUSION

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