2006 AWMA Mega Symposium - CORMETECHcormetech.com/brochures/Mega_Symposium_2k6_SCR_Catalyst_Mana… · yAIG Tuning/Distribution Measurement ... yUse of SCR Bypass with boiler in operation

August 28-31, 2006 2006 MegaSymposium

2006 AWMA Mega Symposium

SCR Catalyst Management Enhancing Operational Flexibility

Cormetech, Inc.Scot Pritchard

Chris DiFrancesco


Agenda

Background on Catalyst ManagementCatalyst Management Planning

Traditional Management ConsiderationsAdditional Considerations

Summary


Agenda



Summary


Catalyst Management

Catalyst Management Process

Optimized SolutionsEconomic Factors

NOx, NH3 Slip, DP Performance Requirements & History

Outage Planning/Impact

Catalyst Type / Regen

Traditional Considerations

Hg Oxidation

SO3 emissions

Operation MethodsFuels Impact

Fleet Considerations

Additional Considerations


Catalyst Management Plan

Catalyst Management Plan2 Initial Plus 1 Spare Layer

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

0 10000 20000 30000 40000 50000 60000 70000 80000 90000 100000

Hours of Operation

Cat

alys

t Pot

entia

l, K

/Ko

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

NH

3 Sl

ip, p

pmvd

c

Catalyst Potential 90%; 2 ppm Slip Threshold 90%; 4 ppm Slip Threshold85%; 4 ppm Slip Threshold NH3 Slip, ppmvdc

Cat

alys

t Pot

entia

l (K

/AV)

Rate of catalyst deactivation depends on fuels and position of layers

Level of performance increase depends on needs and methods i.e. SO2 conv., higher SA, higher activity, etc.

Threshold moves based on performance requirement and system capability

Interaction w/ outage plan


Agenda



Summary


Performance Requirements & History

Performance RequirementsCatalyst performance vs. expectationsFuels monitoring – current vs. future



Catalyst testing & sampling methodologyFull elements / plates from each layerMolar ratio 1 vs. design MRSO2 conversion

Appropriate aging of samples

Qualification of regeneration process

AIG Tuning/Distribution MeasurementPotential for AIG and mixing optimization

TVA Cumberland 1

Fresh

2005 Audit

2003 Audit

2004 Audit

0.5

0.6

0.7

0.8

0.9

1.0

1.1

0 4,000 8,000 12,000 16,000 20,000

Operating Hours

K/K

o

Threshold

K/Ko vs. Operating Hours

Design Deactivation Curve



Catalyst and system inspectionsLPA mitigation considerations

Screen, perforated plate, or aerodynamic design

Catalyst type and pitch selection

ExperienceQualification process


New vs. Regeneration

Case SpecificCatalyst type

Honeycomb and plate have regeneration history$ per K*SA must be comparedConsideration of product advancements

Life extension vs. outage costRegen=more frequent vs. New=less frequent

Capabilities vs. Guarantees and IntegrationKo, K/Ko, SO2 conversion, Hg oxidationMaximum NOx removal efficiency


Outage Alignment

Catalyst Addition/Replacement timingEvaluation very utility dependent

Seasonal vs. Year RoundUse of SCR Bypass with boiler in operationCost of outageFlexibility on NOx reduction and NH3 slip requirements

Rate based vs. tonnage based

Preparedness for SCR work during forced outage


Economic Impacts

Utility Specific, e.g.Capital vs. O&MOutage timing and costUnit capacity factor NOx credit valueAmmonia costSO3 mitigation costCatalyst cost per K/AV or K*surface areaNear term vs. long term evaluation


Agenda



Summary


Fuels

Historical vs. FutureCatalyst performance predictability

High arsenic fuelsPRBPetcoke

Optimization of catalyst formulation based on fuel planFuel additives


Operation Methodology

Removal Efficiency vs. TimeTake advantage of K/AV installed to achieve lower NOx emissions

Applicable to tonnage based emission limitsCan increase system flexibility

OptimizeAIG / Mixer

EvaluateSensitivity to NH3 slip

APHAsh

Catalyst Management Plan2 Initial Plus 1 Spare Layer

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

0 10000 20000 30000 40000 50000 60000 70000 80000 90000 100000

Hours of Operation

Cat

alys

t Pot

entia

l, K

/Ko

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

NH

3 Sl

ip, p

pmvd

c

Catalyst Potential 90%; 2 ppm Slip Threshold 90%; 4 ppm Slip Threshold85%; 4 ppm Slip Threshold NH3 Slip, ppmvdc

Cat

alys

t Pot

entia

l


Operation Methodology

Expansion of Operating RangeExpansion of operating range and flexibility thru allowance of ABS formation on continuing cyclic basis

500 MW plant with a baseline of 0.55 lb/mmbtu and 90% reduction can be worth over $200,000 (ref. $2000/ton NOx credit value) after 200 hours

Load vs. SCR Temperature

100

200

300

400

500

600

500 550 600 650 700

Temperature, F

Load

, MW

0

20

40

60

80

100No

x Re

duct

ion

Eff.

%

Area of Lost Nox Reduction

Load vs. SCR Temperature

100

200

300

400

500

600

500 550 600 650 700

Temperature, F

Load

, MW

0

20

40

60

80

100

Nox

Redu

ctio

n Ef

f. %

Regained Nox Reduction


Operation MethodologyLiquid ABS temporarily reduces activity

Catalyst type and properties will influence capability Evaluate performance requirement vs. total K/AV available

Kinetic effectsCatalyst age Operation time vs. Recovery timeCharacterization of SO3 and NH3 spike during recovery

Catalyst Pore

Active Surface Layer

O2

Bulk Gas Flow

T > Dew Point

Bulk Gas Flow

T < Dew Point

Liquid ABS

NONO

NO

NONH3

NH3NH3

NH3

N2

N2

H2ON2

N2

H2O

H2OH2O

H2O

H2O O2

NONO

NO

NONH3

NH3

NH3

NH3

N2

N2

H2ONH3

NO

NH3NO

H2O

H2O

[NH3(g) + SO3(g) + H2O(g) ↔ NH4HSO4(l)](ABS)

PABS = PNH3 PSO3 PH2O = 1/K

Catalyst Pore

Active Surface Layer

O2

Bulk Gas Flow

T > Dew Point

Bulk Gas Flow

T < Dew Point

Liquid ABS

NONO

NO

NONH3

NH3NH3

NH3

N2

N2

H2ON2

N2

H2O

H2OH2O

H2O

H2O O2

NONO

NO

NONH3

NH3

NH3

NH3

N2

N2

H2ONH3

NO

NH3NO

H2O

H2O

[NH3(g) + SO3(g) + H2O(g) ↔ NH4HSO4(l)](ABS)

PABS = PNH3 PSO3 PH2O = 1/K


Fleet Considerations

InterchangeabilityCommon sparesAlternate product qualificationRegenerationDisposal and recycling options


SO3 Mitigation

High Performance Catalyst Allows reduced SO3 emissions with excellent NOx reduction performanceProduct features conversion rates as low as < 0.1% for single layer additionsFurther advancements under developmentProduct can be used in combination with in-furnace and post SCR mitigation techniques

Product Case 1 Case 2

Product PitchOpening

(mm) GSA

(m2/m3)

Relative Volume Required

Relative Pressure

Drop

Relative Volume Required

Relative SO2

Oxidation Required

Conventional 7.4 6.3 445 100% 100% 100% 100% High Performance 6.9 6.3 539 75% 61% 100% 25%


Hg Oxidation

Catalyst Life vs. Hg Oxidation CapabilityModel developed since 2003Predictive capabilityon range of fuels vs. catalyst lifeGuarantees availableMHI patented approach for low Cl coals

Predicted SCR Hg Oxidation - Example Bituminous-Fired Unit

0

10

20

30

40

50

60

70

80

90

100

0 50 100 150 200

Concentration of Cl Species at SCR (ppm)

Ele

men

tal H

g O

xida

tion

(%)

New SCR CatalystAged SCR Catalyst

Predicted vs. Actual SCR Hg - Large Utility Unit at

Full Load After Several Ozone Seasons

60

70

80

90

100

0 10 20 30 40 50 60

HCl(g), ppmvd

Out

let H

g+2,

% Predicted

Actual (4-testavg.)Individual Tests


Agenda



Summary


Summary

• Traditional Considerations– Catalyst Type

• $ per K/AV or K*SA– Costs associated with outages – Pressure drop associated with added layer(s)– Sensitivity to NH3 slip– New catalyst vs. regeneration

• Additional Considerations– Operation and Performance goals (NOx removal, Tmin, etc.)– Future fuels– Fleet management– SO2 oxidation limits – Hg oxidation– Catalyst & replacement methodology advancements

Use basic tools for initial evaluation but ……need to keep up with current issues and future technology to optimize process


Thank you!

Questions?

Documents

2006 AWMA Mega Symposium - CORMETECHcormetech.com/brochures/Mega_Symposium_2k6_SCR_Catalyst_Mana… · yAIG Tuning/Distribution Measurement ... yUse of SCR Bypass with boiler in operation