CO2 Capture with Foster Wheeler´s

Flexi-burnTM CFB Technology

Reijo Kuivalainen

Foster Wheeler Energia Oy

ClimBus programme seminar, June 9-10th, 2009

Contents of Presentation

• Background: CFB technology basis, CO2 reduction and CO2 capture and storage (CCS) options

• Oxy-fuel CFB combustion: principle, advantages and challenges

• Development of Flexi-burnTM CFB boiler

• Test results of pilot scale experiments

• Conclusions

67 %

18 %

9 % 4 % 2 %COALS

PET COKE

BIO

LIGNITE

OTHERS

Foster Wheeler is the market leader in Circulating Fluidized

Bed Technology

350 CIRCULATING FLUID BED (CFB) BOILERS

• Total 24 000 MWe CFB sold

• 309 in operation for variety fuels:

coal, lignite, petroleum coke, biomass,

RDF, etc.

• 32 under construction

• Biggest unit in operation 300 Mwe

• 465 Mwe OTU CFB started up

Tot. >24 GWe CFB

Foster Wheeler Fluidized Bed Technology Basis

Nearly 30 Years and 22 Gwe

Foster Wheeler Energia Oy in Finland is the Technology Center for Fluidized Bed Boilers in Foster

Wheeler Global Power Group

Foster Wheeler Develops CFB Technology to

Meet Future Challenges of Power Generation

• scaling up the CFB technology

• increasing efficiency

• improving environmental performance

• widening the fuel flexibility

• adapting CFB for CCS

BackgroundMainstream CCS Technology Options with Fossil Fuels

• Short and medium term approach to CO2

reduction:

• Increase of efficiency

• Co-firing of coal with fuels considered CO2

neutral

• Main technology options for CO2 capture in power production

• Post-combustion capture

• Pre-combustion capture

• Oxy-fuel combustion

BackgroundImpact of Efficiency and Improvement and biomass co-firing on CO2 Reduction

100% coal

Thermie Ultimo

Thermie SR

Average Europe

CFB today

10% biomass

20% biomass

400

500

600

700

800

900

1000

1100

1200

25 30 35 40 45 50 55 60

Net efficiency (lhv, %)

2 CO emission (g/kWh)

% biomass on LHV

21%

34%

BackgroundCCS Technology Development at Foster Wheeler

• GHG emission trading systems and/or emission caps are expected to lead into demand for solutions to near zero emission power (and heat) production of fossil fuels

• CCS-ready new plants – retrofits – greenfield plants with CCS

• Of the main technology options, FW is mainly focusing on Oxy-fuel combustion in CFB boilers

• The Oxy-fuel CFB development is carried out in Finland

• Development carried out in parallel as

• Internal development (modeling/design tools, boiler engineering, economics,...)

• Partnership in R&D with research institutes and universities (pilot testing, modelling, etc.)

• Participation in public R&D

• Demonstrations

Oxy-Fuel Combustion Process

Steam

turbine

Flue gas

recycle

BoilerCompression

Purification

Flue gas

cleaning

CO2

Air Air separation N2, (Ar)

G

Coal

CO2/H2O

H2O

Condensation

Transport

Storage

Vent gas95-99+% O2,

(Ar, N2)

Oxy-Fuel CFB TechnologyMain Advantages

• The established CFB advantages exist also in CFB

oxycombustion: low furnace temperatures, hot

circulating solids, long solid residence time

• Multi-fuel capability (coal, petroleum coke, lignites,

biomasses), simple feed systems – capability to utilize

cheap fuels emphasized due to CCS efficiency penalties

• SOx and NOx reduction without scrubbers

• Good fuel burnout and sorbent utilization

• Efficient heat transfer and uniform heat flux

• Enables Flexi-burnTM CFB boiler design: the same boiler

can be operated in air firing or oxy firing mode with CCS

• Further potential: high O2 contents (> 30 – 35 %)

Flexi-BurnTM CFB

Large scale

high efficiency

CFB boiler with

FLEXI BURN

designFuel

Bituminous coal

Lignite

Biomass

Pet coke etc.

ASU Mixing

Air

O2

Switch

Fluegas

(CO2-rich)

Flue gas recirculation

Switch

To stack

CCS

CO2 capture

and storage

Large scale

high efficiency

CFB boiler with

FLEXI BURN

designFuel

Bituminous coal

Lignite

Biomass

Pet coke etc.

Fuel

Bituminous coal

Lignite

Biomass

Pet coke etc.

ASU Mixing

Air

O2

Switch

Fluegas

(CO2-rich)

Flue gas recirculation

Switch

To stack

CCS

CO2 capture

and storage

• Oxy-ready design for

subsequent

implementation of CCS

• In greenfield installations

with CCS, the concept

serves risk mitigation

intrests by enabling power

production e.g. in case of

unavailability of storage

facilities.

Oxy-CFB TechnologyChallenges for developing CFB for Oxy-fuel

At moderate O2 concentrations:

• Combustion behaviour

• Heat transfer

• Materials (corrosion, deposits)

• Prediction of emissions

• Controls

• Gas properties change

• (, cp, etc.)

• Hydrodynamics

28

40

60

80

100

0

10

20

30

40

50

60

70

80

90

100

0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000

T adiabatic [°C]

ho

t lo

op

/to

tal h

ea

t d

uty

[%

] 0

10

20

30

40

50

60

70

80

90

100

O2

sh

are

if inp

ut g

as

[%]

Existing CFB units / designs

O2 CFB designs

O2 share of input gas (O2/CO2)

normal air

combustion

At high O2 concentrations additionally:

• Adiabatic combustion temperature rises.

• The generated heat per volume is substantially higher.

• Flexi-burn firing more challenging (air and oxy in the same boiler)

Oxy-Fuel TechnologiesEfficiency Penalty

• Maximizing gross efficiency to minimize

penalty

• Reduction of oxygen production costs

• High internal power consumption

Cooling

1084MW

(53.5%)

Efficiency

(net),

%

05

1015202530354045

Refe

ren

ce

pla

nt

O2/C

O2

pla

nt

Fuel input

2026MW

100%

Original

electricity

output 865MW

(42.7%)

CO2 compression

71 MW – 3.5%

Air separation

137 MW – 6.8%

Auxiliaries

45 MW – 2.2%

Air separation and CO2 compression

requires massive amounts of energy......resulting in 8-12 %-

points lower efficiency

689MW

output –

34%

Source: Chalmers / Andersson

• System-level integration

• Space requirements

80 m

Flue gas

recycle

Oxygen

Flue gas

condenser

100 m

Oxy-Fuel TechnologiesRequires large space for ASU and CPU

Development of Flexi-BurnTM CFBMain Activities

• Foster Wheeler has been developing oxy-fuel CFB combustion since 2003:

• Knowledge and design tool development

• Test activities (VTT bench scale & small pilot CFB)

• Conceptual and feasibility studies (boiler design)

• In parallel, scale-up of air-fired CFB boilers has continued. FW is starting up the world largest and first SC-OTU CFB at PKE’s Lagisza plant in Poland and develops CFB technology further up to 600-800 MWe size with 600 °C steam temperature.

• The Spanish government has decided on investment for the CIUDEN 30 MWth

class pilot CFB facility, which provides a full experimental CCS platform for the demonstration and validation of oxy/air-fuel combustion in sufficient scale to allow continuation to commercial scale.

• FW has provided basic engineering of the CFB and PC boilers and negotiates for the supply contract of the boilers.

• Experiences in scale-up of CFB boilers up to 460 MWe size and on the other hand in planned air / oxy firing demonstration in 30 MWth size will be combined.

Develop the Flexi-burn CFB boiler concept and demonstrate the technology.

• Endesa Generación plans to demonstrate a 500 MWe scale Flexi-burn CFB for CCS within EU’s flagship CCS demonstration program.

• FW together with Praxair will provide the technology for the CFB boiler and carbon capture.

• Feasibility studies with other utilities

• FWNA is cooperating with Praxair in the development of 50 MWe Oxy-CFB demonstration at Jamestown plant in New York state.

Development of Flexi-BurnTM CFBMain Activities

Development of Flexi-BurnTM CFBScale-up Path

Demonstration of Flexi-burn CFB15 – 30MWth

• Air-/ oxyfiring with fuel flexibility

• CO2 separation

Lagisza 460 MWe OTU CFB• Scale-up information from the world's largest CFB

• Experiences of the world's first SC OTU CFB

• Design model validation

Commercial scale

Flexi-burnTM CFB

technology in

>500 MWe size

Scale-up

criteria

Existing know-how• Supply of over 300 CFB boilers up to 300 MWe

• Long-term development of design tools

Oxy-CFB Testing and Development

nc Xkm

t

mr O2c

c

d

d

COefCO Ykt

Y

d

d

)/1/(1 mCOef kk

nrefv ddTAb )/)(/exp(

Model

analyses

CO combustion

Mixing

Char combustion

Volatile,

moist

ure re

lease

Figure 2 Furnace heat flux

kW/m

2

1D-MODELflue gas

1

n n+1

to stack

Primary airSecondary air

2

n-1

3

n-2

ŁAGISZA 460 MWe supercritical OTU CFB

kW/m2

Bench scale Pilot scale Boiler scale

EXPERIMENTAL

SCALES

Models for

phenomena1-D Process

models3-D Process

models

MODELS AND

DESIGN

TOOLS

Oxy-CFB ExperimentsVTT Test Facilities

• Experimental oxy-fuel combustion studies

with small scale fluidized bed combustors at

VTT in Jyväskylä since 2004

• Pilot scale (30-100 kW) circulating fluidized

bed (CFB) reactor

- Combustion with O2 + recycled flue gas

- Combustion with bottled gases

- Air firing

• Bench scale BFB/CFB reactor (< 1 kW)

suitable for studies of oxygen combustion

phenomena

M

Secondary

cyclone

Fuel containers 1 and 2 Zone 1

Zone 2

Primary

cyc lone

Observation port

Deposit probe port

Zone 3

Zone 4

To stack

Sampling port

Sampling port

Sampling port

Additivecontainer

Air

Secondary gas

Primary gas heating

O2, CO2, N2

PC control and data logging system

Sampling por t

Sampling port

G as analysat or

FTIR sampling port

FTIR sampling port

Sampling port

Sampling port

Gas coolingBag filt erFlue gasrecirculation

M

Secondary

cyclone

Fuel containers 1 and 2 Zone 1

Zone 2

Primary

cyc lone

Observation port

Deposit probe port

Zone 3

Zone 4

To stack

Sampling port

Sampling port

Sampling port

Additivecontainer

Air

Secondary gas

Primary gas heating

O2, CO2, N2

PC control and data logging systemPC control and data logging system

Sampling por t

Sampling port

G as analysat or

FTIR sampling port

FTIR sampling port

Sampling port

Sampling port

Gas coolingBag filt erFlue gasrecirculation

PILOT SCALE CFB COMBUSTOR

M

Secondary

cyclone

Fuel containers 1 and 2 Zone 1

Zone 2

Primary

cyc lone

Observation port

Deposit probe port

Zone 3

Zone 4

To stack

Sampling port

Sampling port

Sampling port

Additivecontainer

Air

Secondary gas

Primary gas heating

O2, CO2, N2

PC control and data logging system

Sampling por t

Sampling port

G as analysat or

FTIR sampling port

FTIR sampling port

Sampling port

Sampling port

Gas coolingBag filt erFlue gasrecirculation

M

Secondary

cyclone

Fuel containers 1 and 2 Zone 1

Zone 2

Primary

cyc lone

Observation port

Deposit probe port

Zone 3

Zone 4

To stack

Sampling port

Sampling port

Sampling port

Additivecontainer

Air

Secondary gas

Primary gas heating

O2, CO2, N2

PC control and data logging systemPC control and data logging system

Sampling por t

Sampling port

G as analysat or

FTIR sampling port

FTIR sampling port

Sampling port

Sampling port

Gas coolingBag filt erFlue gasrecirculation

PILOT SCALE CFB COMBUSTOR

Oxy-CFB ExperimentsEmissions in Pilot Scale Tests

SO2 Emissions and Calcium

Utilization with Bituminous Coal

NO Emissions with Bituminous Coal

Heat Fluxes of the CFB Furnace are Favourable for Oxycombustion3D Modelling Results

Air combustion Oxy Combustion

50

40

35

30

25

20

15

10

5

0

45

0 100 200 300 400

Fu

rnac

e H

eig

ht

[m

]

Heat flux (average) [kW/m²]

PC furnace

CFB furnace

Comparison of heat fluxes in CFB and PC

Air Combustion

www.oxygenie.com

Flexi-BurnTM CFB Boiler DevelopmentSummary

• Development approach based on theoretical studies, experiments at different scales, compilation of the acquired know-how in design tools / process models used in designing boilers

• The Lagisza 460 MWe CFB boiler has been used as a reference in oxycombustioncase studies (retrofit & greenfield Flexi-burnTM CFB)

• Prediction tools show studied oxy-fuel boiler configurations viable.

• Experimental results from bench and pilot scale test units show good emission performance.

• Adapting an existing CFB boiler design for oxycombustion appears technically feasible without major changes in the boiler structures and heat surfaces.

• Uncertainties in prediction of large scale performance will be eliminated

Models are being modified and testing continued to consider oxycombustion characteristics

Demonstration in 15 – 30 MW scale scheduled to start in 2010

Capability to offer Foster Wheeler Flexi-burn design by 2011

www.oxygenie.com

Thank You!