St. Johns River Power ParkSt. Johns River Power Park2 x 670 MW SCR2 x 670 MW SCRDesigned to Ensure Fuel FlexibilityDesigned to Ensure Fuel FlexibilityGerald Smith – SJRPP – Project ManagerRobert Branning – Tackticks – Project EngineerMEGA Symposium – Baltimore, MDAugust 26, 2008Contributing Authors•Gerald Smith - SJRPP•Robert Branning – Tackticks, LLC.•John Cochran – CERAM Environmental•Diane Fischer – Black & Veatch•Kathryn Robinson – Black & Veatch•Noel Rosha – CERAM Environmental•Volker Rummenhohl – Tackticks, LLC.Presentation Agenda•Project Overview•Fuels – Challenges•Operating Challenges•Catalyst Selection•CoPilot®Catalyst DemoTest Results•Balance of Plant ConcernsProject Overview•Two Units – Each 670 MW (gross)•Two 3+1 SCR Reactor Boxes per Unit (14 x 6 Frames)•Fuels – Domestic Coal / Colombian Coal / Petcoke•High Flue Gas Temperatures – 750 to 800° F•Catalyst Procurement Including Co-Pilot®Catalyst Testing•LPA Capture – Aerodynamic and Screen Removal System•SO3Control System (Ammonia)Unit Load Vs. Econ Outlet Temp4004505005506006507007508008509000 100 200 300 400 500 600 700 800Gross Generator Load, MW

Economizer Outlet Temp, FFuels – ChallengesEffects on SCR Design, Catalyst Performanceand Catalyst LifeFuels – Challenges and RisksFuel(Blend Portion)ChallengesRisksDomestic Coal(35 to 100%)High Arsenic (up to 30 ppm)Low Calcium Oxide (down to0.5%)Rapid Catalyst DeactivationColombian Coal(35 to 100%)High Silica in Fly Ash (up to62%)Catalyst and DuctworkErosionPetroleum Coke(0 to 30%)High Sulfur (up to 6.94%)High Vanadium (>2,000 ppm)High Loss on Ignition (LOI)Min Operating TempsIncreasing SO3EmissionsIncreased Fire PotentialLimited Experience With PetcokeBlends in SCR ApplicationsDirect Bunkering of Fuels•Fuels Fired Separately•Design Considered Flue Gas “Channeling”•Possibility for Targeted AffectsCL Burners7 RowsDECFBGACoalPetcokeCoalCoalPetcokeCoalBoilerGas FromBoilerSCRReactorReactor Construction - July 11, 2008Site Construction - FansSite Construction – LPA ScreensSite Construction – Catalyst InstallationOperating ChallengesOperating Challenges•Plant Characterization Testing•Full Load and Low Load Operation•Mill Configuration•Fuel Combinations•Ductwork / Reactor Design•Control of SO3Emissions•Control of LPA Carryover into SCR•Maintain Plant ReliabilityCatalyst Design, Selection andCoPilot®Test ResultsEnsuring Performance and ReliabilityDespite the ChallengesCatalyst Characterization Testing and Selection•Predominant Objectives for Catalyst Procurement•Initial Low Oxidation Rate•Maintain Low Pluggage•Good Possibilities for Rejuvenation/Regeneration•CoPilot®In-Situ Catalyst Demonstration Testing•Characterize SO2to SO3Conversion Rate Changes•Characterize Catalyst Activity Changes•Tested Plate and Honeycomb(2 Suppliers) Catalyst onRotating Basis Between 3 CoPilot®Test Units•CERAM Homogeneous Honeycomb Catalyst SelectedBased on Comprehensive Technical and CommercialEvaluation•0.25% Oxidation Rate (3 Layers)•8.2 mm Pitch/1.0 mm Wall ThicknessCoPilot®Test ReactorCoPilot®Door ActionAir SideFlue Gas SideAllows for Catalyst Test ElementRemoval Without Unit OutageRotated IntoFlue GasRotated Outof Flue GasRotating Test ReactorDoor Into Gas StreamCoPilot®Test ResultsSampleIDRelativeActivity,K/KoRelativeSO2to SO3ConversionRate, %Hours ofOperationFuels Fired (% of heat input)ColombianDom CoalPetcoke4083 1.0 1.0 01.11 1.0 956 56 16 274084 1.0 1.0 01.10 1.09 2,135 27 43 300.93 1.47 7,280 37 34 295011 1.0 1.0 00.85 1.0 4,535 63 35 25012 1.0 1.0 01.01 1.13 5,145 44 28 28CoPilot®Test Results (cont’d)CoPilot®Test Results (cont’d)Catalyst Design ChangesFollowing Procurement•Fuel Changes Occurred Late in the Project•Petcoke Firing Currently Not Attractive•Catalyst Redesign Required for Current Fuels•Possibility of Petcoke Returning to Fuel Mix0%20%40%60%80%100%120%140%160%0 5000 10000 15000 20000

Required Reactor PotentialOperatingHoursSJRPPReactorPotential(18,000HourSizingBasis)WithPetroleumCoke(lowdeactivation)WithoutPetroleumCoke(highdeactivation)Revised Catalyst DesignOriginal Contract Basis (2006) Revised Catalyst Design (2007)Fuel Blend Basis 70% Coal/30% Petcoke 100% CoalCatalyst Pitch 8.2 mm 8.2 mmCatalyst Volume 770 m3770 m3Catalyst Deactivation Basis Low Deactivation(K/Ko=0.88) due to 30% petcokeblendMedium-High Activation(K/Ko=0.65) due to higharsenic/low calcium oxideCatalyst Wall Thickness 1.0 mm 1.0 mmInitial Oxidation Rate 0.25% (Ammonia Off/800 F)with 3 catalyst layers installed2.0% (Ammonia Off/775 F) with3 catalyst layers installedGuarantee NOxOutlet 0.06 lb/MBtu(85% NOxreduction)0.06 lb/MBtu(85% NOxreduction)Guarantee Life 18,000 hours 18,000 hoursBalance of Plant ConcernsMaintaining Plant Operational ExcellenceThroughout the ProjectBalance of Plant Concerns•Limestone Addition System•Increases calcium content in fly ash – mitigates Arsenicpoisoning effects on catalyst•Limestone metered and deposited onto coal conveyorwhenever domestic coal is transferred•SO3Control System•Injection of ammonia downstream of air heater•Upgrade of existing systemBalance of Plant Concerns (cont’d)•Large Particle Ash (LPA) Capture•Aerodynamic baffles at economizer outlet•LPA screen upstream of SCR inlet•Air Heater Modifications•ABS resistant design•Multi-media cleaners on hot and cold end•Fan Modifications•New ID Fans•Upgrade of FD and PA FansSummarySummary•SCR Design Can be Targeted toMaintain Fuel Flexibility•Careful Design, Coordination, andTeam Support are Essential•Plant Reliability Can Be MaintainedDespite Design Challenges