MechanicalMaintenanceDepartmentElectricityGenera2ngAuthorityofThailand

4Moo.6BangpakongPowerPlant,ThaKam,Bangpakong,Chachoengsao,Thailand

FUELOILDIFFUSIONSYSTEMCLEANINGFORGASTURBINE(MODEL:SIEMENSV94.3A)

IssaraPongsawanParinyaPanyananAdisornSrimoonTarmjaiJi4rakij

EGATElectricityGenera2ngAuthorityofThailand

-CompanyBackground-

Maintainability !

Efficiency !

Availability !

Reliability !

2 !

BANGPAKONGCOMBINEDCYCLEBLOCK5(BC5)

3 !ReferenceAvailable :hFp://www.marubeni.com/dbps_data/news/2006/061026e.html[Accessed19Sep2016]

TypeofPowerPlant: ���Gas-firedorOil-firedCombinedCycle,710MW•  2unitsofGasTurbineGenerators;

CalledasGT51andGT52innewtechnologyHybridandDryLowNoxBurner

•  2unitsofHeatRecoverySteamGenerator(HRSG)

•  SteamTurbineGeneratorx1

REMARKNOxstandforNitrogenOxide;NOandNO2

DIFFUSIONFLAME

PREMIXFLAME

4 !

DiffusionFlame

FlameTemperatureandNOxEmission

5 !

AnalyzeinacaseofBC5wasnotabletooperateinoil-firedmodein2015

StartUp CleanLanceTube(inDiffusionBurner)NO

YES

OperatetoreachBaseload(250MW)

LoadIncreasedbyDiffusionMode

SwitchfromDiffusionModetoPremixmode

LoadIncreasedbyPremixMode

YES

NormalOpera]on

NO

RecalibrateOutletTemperatureControl 6 !

PURPOSEOFPROJECTPROBLEM:Cannotdo7-dayshutdownplantto

cleanthefueloillancetubes

So,Objec]veisto

Shortenprocessing]metomakeitfitto

Combus]onInspec]on1-yearonce

7DayOutage

NormalSolu]on:

Take7daysduringplantoutagetocleanequipment

MajorOverhaul6-yearonce37DayOutage

HotGasPathInspec]on(HGPI)

3-yearonce27DayOutage

7 !

BC5PLANOUTAGEINTERVAL

HotGasPath

Inspec]on3Year

CI1Year

MajorOverhaul(6Year)

*Combus2onInspec2on(CI)

37Days(MO)

7Days(CI)27Days(HGPI)

8 !

LIST OriginalCleaningProcess Dura]on ModifiedProcess Dura]on

Inspec2on

DisassemblingallcomponentsinsidesCombus2onChamber

2Days

-DisassemblingBurnerFuelOilLanceTubes(only) 0.5Days

Inspec2onbyBoroscope -Inspec2onbyBoroscope

ChemicalSec2on

Immersioncleaningincitricacidinultra-sonicbath

2Days

-Immersioncleaninginoilremoverwithpump

0.75DaysRisingwithpump -Risingwithpump

FlushandPassiva2on -

ReverseBlowoffandSucking -ReverseBlowoffandSucking

Preserva2on -

Inspec2on(AcerClean)

Inspec2onbyBoroscope

3Days

-Inspec2onbyBoroscope

0.5DaysFlowMeasurement -

Repor2ngacercleaningAssemblingBurnerandSwirler

-AssemblingLanceTubes

Total 7Days 1.75Days9 !

MODIFYPROCESSFORFASTERDISASSEMBLINGTUBE

(c)Aheadofburnerfueloillancetubethatlockwithaplant

(b)Aburnerfueloillancetube

Figure2!

10 !

(a)Aplate;usestoconnectaboltforpullingburnerfueloillancetubeoff

FASTERDisassembletheLancetube

STEP 1 : Disassembling only Burner Fuel OilLance Tubes by using an orange plate(Figure3-4) combined with bolts to holdt h e t u b e s o u t f r o m b u r n e r . !

Figure3:Anorangeplatewithtwobolts–atoolusestoholdburnerfueloillance

tubeandthenpullthetubeoff

11 !

Figure5:BurnerFuelOilLanceTubes

Figure4:duringusesaplanttoholdburnerfueloillancetube

12 !

Inspec2onResult-BeforeCleaning-

SeeinthisFigure7:

Insideoftheburnerfueloillancetubethathadoilstain

Figure6:BurnerFuelOilLanceTubes

ChemicalCleaningSec]on

13 !

Theburnerfueloillancetubeswereimmersedinoilremoverwhichhaschemicalpropertytocleanoilstainas

citricaciddoes.

Circulatethesolu]onbypumpfor12hours

Remark:preferultrasonicbathsystem.Butifthebathisnotavailablesoyoucanusecircula2onand

takelongersoaking2meinstead

Original ! New!

1.Citricacid! 1.Oilremover!2.UsingUltrasonicBathtakesafewhoursper6tubes!

2.Circulatethesolu]onbypumpfor12hoursforalltubes(24tubes) !

Figure8:12hourschemicalimmersionforwashingtheburnerfueloillancetubes

Inspec]onResultcomparebetweenoriginalandmodified(new)methods

Figure9:Cleansurfaceoftheburnerfueloillancetubeacerwashingprocess

14 !

Conclusion

1.DecreasingmanhourforBurnerWashingprocess2.ProvidingfirmFuelOilOpera2onreliabilitytoPowerPlant3.Inemergencycaseofunabletostartupplantduetohotspot,thetrainedstaffsinpowerplantcanimplementthiscleaningprocessthemselvesin2days.

Benefit

Burnerwashingprocesswasselectedtosolvethehotspotissue

TroubleShoo]ng1.Fueloilopera2onfailedinDiffusionModeduetohotspotissueAssump2on:Causeoffailurewerecokingandoilstaininburner2.Combu2onInspec2onDura2on(7days)was2meconstraintofindoutsuitablesolu2onforhotspotissue

Troubles

OriginalBurnerCleaningProcedure

7days !

NewBurnerCleaningProcedure

2days !

Created

15 !

THANKYOUFORYOURATTENTION!