FIELD TEST OF A 1.5 MW INDUSTRIAL GAS TURBINE WITH A LOW EMISSIONS

CATALYTIC COMBUSTION SYSTEM

Ralph A. Dalla BettaSarento G. NickolasChrisK. WeakleyKare LundbergCatalytica Combustion Systems, Inc.

Combustion Systems

Tim J. CaronJohn ChamberlainAgilis Group, Inc.

Kevin GreebWoodward Governor Company

Catalytica Combustion Systems, Inc.

Program Objectives and Strategy

Combustor to be a demonstrator of catalytic technology– Materials selected to minimize development time– No size limitations

Basic engine/combustor approach– No modifications to gas turbine– Combustor change out at combustor flange– Natural gas fuel only

Performance targets– Emissions over 90 to 100% load range and wide ambient

NOx < 3 ppmCO < 5 ppmUHC < 5 ppm

– Minimal impact on turbine performanceCombustor outlet temperature of 1300°C (2400°F) to demonstrate catalytic combustion technology for wide range of engines

Catalytica Combustion Systems, Inc.

Schematic of combustor configuration

Preburner provides required catalyst inlet temperatureCatalyst fuel injector produces a uniform fuel/air mixture for the catalystHigh post catalyst temperature oxidizes CO to < 10 ppmBypass and cooling air provides required turbine inlet temperature

CompressorPr

ebur

nerCat a lyst Burn out

zoneT urb ine

Byp ass/ cooling airFu

el I

njec

tor

330°C 630°F

450°C 840°F

1300°C 2370°F

1010°C 1850°F

Catalytica Combustion Systems, Inc.

One Aspect of Catalyst System

Metal or ceramic substrate

Washcoat layer

Gas flow

High surface area oxide support

Catalytic component dispersed on the oxide support

Monolith

Catalytic

Non-Catalytic

Temperature controlled by “Integral Heat Exchange” structure that limits catalyst temperature below adiabatic combustion temperature

Catalytica Combustion Systems, Inc.

Integral Heat Exchange

Integral heat exchange (IHE) limits catalyst temperature

Bulk flow

Boundary layerCatalyst

Foil substrate

Boundary layer

Bulk flow

ProductsReactants Rxn heat

Rxn heat

Ts = Tin + ² Tad

2

• Solid cross-section essentially isothermal • Equal heat transferred to catalyzed and non-catalyzed channels • Maximum conversion = 50% • Maximum wall temperature = Tin + ² Tad • Example: Inlet gas T = 700°C (1290°F) Tad = 1300°C (2370°F) non-IHE wall T = 1300°C(2370°F) IHE wall T = 1000°C (1830°F)

12

Catalytica Combustion Systems, Inc.

XONON 1 Catalyst performance and operating line

1 3 0 01 2 0 01 1 0 01 0 0 09 0 08 0 07 0 07 0 03 0 0

4 0 0

5 0 0

6 0 0

7 0 0

8 0 0

Burnout z one t emperat ure ( °C)

Cat

alys

t in

let

tem

pera

ture

(°C

)

0 22 36 55 70 84 10 0Load ( %)

Syst em limit

CO < 1 0 pp m

UHC < 1 0 0 ppm

UHC < 1 0 0 0 ppm

Comp resso r discharg e

Op erat ing line

• Measured on Sub-scale rig at operating conditions

Catalytica Combustion Systems, Inc.

XONON design flexibility

Surface

All of fuel

All of airInlet

catalystOutlet

catalystHomogeneous

combustion

Tad

TemperatureGas

• Higher wall T (designlimits max wall T)

• High outlet gas T

• High activity• Low lightoff T• Designed for low wall T

Sufficient time to:• Complete CH4 combustion• Complete UHC and CO burnout

Catalytica Combustion Systems, Inc.

Combustor cross section

Stage 1 catalystStage 2 catalyst

Post catalyst reaction zone

Infrared camera

Primary tube exit

Secondary tube

Preburner

Preburner exit gas sample

Catalyst fuel injector/mixer

Catalyst inlet gas sample

Slots

Catalytica Combustion Systems, Inc.

Preburner Design

RequirementsTemperature rise of 700°C (1200°F) during starting and accelerationLow emissions load range requires 80 to 150°C(150 to 270°F) temperature rise NOx contribution at engine exhaust < 2 ppm over low emissions load range

DesignLean premix swirl stabilized primary

– Operates from LBO+20% to NOx limitLean premixed parallel secondary ignited by primaryMore then 50% of combustor air flow is added downstream of the primary and secondary prior to catalyst inlet

Catalytica Combustion Systems, Inc.

Preburner: Perspective View

Preburner liner

Axial entry secondary mixing tube

Tangnetial entry primary mixing tube

Dilution flow

Catalytica Combustion Systems, Inc.

Catalyst Fuel-Air Mixing System

RequirementsFuel-air mixture uniformity < ± 3% of mean at catalyst inletNo recirculation or stagnation zones that would hold flame downstream of fuel injection

DesignPreburner exhaust flow is reversed to enhance temperature uniformity upstream of the fuel injectorFuel is injected upstream of counter rotating swirlers

– 36 swirl vanes and 36 fuel injection pegs– Counter rotating flows promote mixing with low

tangential velocity just upstream of the catalyst

Catalytica Combustion Systems, Inc.

Catalytic Module

~95% open area for low pressure dropAll metal structure for thermal shock resistance

Catalytica Combustion Systems, Inc.

Engine Test Cell Layout

Air intakeDynamometer water cooling tower

Air eductor

Dynamometer

Air intake

Gear box

Gas turbine

Catalytica Combustion Systems, Inc.

On Engine Preburner Testing

Static pressure tap downstream of mixed preburner exhaust used to measure gas compositionEngine operated at part load Fuel to preburner primary and secondary could be varied over a reasonable range

– Must stay within catalyst operating zone– Engine was operated in speed control mode with set

dynamometer load

Catalytica Combustion Systems, Inc.

Primary Zone PerformanceMeasured at preburner exitNo secondary fuel

0

50

100

150

200

250

300

0.6 0.7 0.8 0.9 1 1.1

Equivalence ratio

CO

and

UH

C (p

pm)

-5

0

5

10

15

20

25

30

NO

x (p

pm)

NOxCO

UHC

Catalytica Combustion Systems, Inc.

Secondary Performance

Primary Ø=0.86Measured at preburner exit

0

1000

2000

3000

4000

0 0.1 0.2 0.3 0.4 0.5

Equivalence ratio

UH

C a

nd C

O (p

pm)

0

1

2

3

4

5

NO

x (p

pm)

UHC

NOx

CO

Catalytica Combustion Systems, Inc.

Secondary Performance

Primary Ø=0.86Measured at preburner exit

0

25

50

75

100

125

150

0 0.1 0.2 0.3 0.4 0.5

Equivalence ratio

Tem

pera

ture

rise

(°C

)

0

1

2

3

4

5

NO

x (p

pm)

Temperature rise

NOx

Catalytica Combustion Systems, Inc.

Fuel-Air Mixer Performance

18 sampling tubes at the catalyst inlet face used to extract mixture for analysis by FID hydrocarbon analyzer

Measurement done under constant dynamometer load with engine in speed control mode

Measurement time was ~20 minutes

Some measurement variation may arise from total fuel variation required for engine control

– Especially large at low catalyst fuel flow

Catalytica Combustion Systems, Inc.

F/A Map at Catalyst Inlet--1065 kW

Results

Relative F/A ratioMin 0.991Max 1.008

Range ± 0.9%O

O

O

O

O

OO

OO

O

O

O

OO

O

O

O

O

-8

-6

-4

-2

0

2

4

6

8

-8 -6 -4 -2 0 2 4 6 8

Y-C

oord

inat

e

X-Coordinate

1.00

1.00

1.00

1.00

1.00

0.990.99

1.001.00

1.00

1.00

1.00

1.011.01

1.00

0.99

1.00

0.99

Catalyst OD

Catalytica Combustion Systems, Inc.

Infrared Image at Full Load (EGT limit)

994125c4

903 C 891 C

870 C

Uniformity = ~ 75 C

Catalytica Combustion Systems, Inc.

Engine Performance

Measured at engine exhaustCorrected to 15% O2

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

16.0

18.0

20.0

0 200 400 600 800 1000 1200 1400

Load (kW)

NO

x (p

pm)

0

20

40

60

80

100

UH

C a

nd C

O(p

pm)

CO

UHC

NOx

Raw NOx

Catalytica Combustion Systems, Inc.

Summary

Combustor designed and fabricated to demonstrate catalytic combustion on a 1.5 MW industrial gas turbine

System operated at base load for 1000 hours

System provides emissions levels of:NOx < 3 ppmCO < 1 ppmUHC < 1 ppm

Catalyst shows good durability to high loading of air contaminants

Combustor dynamics were very low