ML17266A022

Reportable Occurrence 335-B-78-08 on 781117:condenser Temp Rise Exceeded 24 F,Caused by Circulating Water Sys Fouling, But Discharge Canal Temp Did Not Exceed 111 F Degrees

ML17266A022
Person / Time
Site:	Saint Lucie
Issue date:	12/14/1978
From:	UHRIG R E FLORIDA POWER & LIGHT CO.
To:
Shared Package
ML17266A021	List: ML17266A020 ML17266A022
References
NUDOCS 7901040157
Download: ML17266A022 (3)

Text

FLORIDAPOWER&LIGHTCOMPANYST.LUCIEUNITNO.1REPORTABLEOCCURRENCENO.335-B-78-08TITLEMaximumCondenserTemperatureRisesA.Descrition,AnalsisandEvaluationReportableOccurrenceNos.335-B-78-03,-'04,and-07describedoccasionsonwhichthecondensertemperatureriseatSt.LucieUnitNo.1wasobservedtobeinexcessof24'F.Furtherin-stancesofthistypeoccurringinNovemberareasfollows:DATETIME6TPOWERFLOW11-17-78200024.loF100%490,000gpm11-26-7811-27-78020024.1F100$485,000gpm070024.3'F100%482,000gpmAswasdescribedintheearlierR.O.'scitedabove,thecircu-latingwatersystemattheSt.LuciePlanthasbeenexperiencingconditionsofsystemfoulingwhichhavecausedthecondensertemperaturerisetoslightlyexceed24'P.TheseconditionsoffoulingmakethetemperatureriseswhichhavebeenexperiencedacceptableasperETS2.1.2.Theseeventsarebeingreported,however,asacontinuingitemofpotentialpublicinterestconcerningenvironmentalimpactfromplanto'perationinaccor-dancewithETS5.6.2.a.Noinstanceofdischargecanaltemperatureexceedingthelimitofill'F(ETS2.1.1)wasobservedatatimecorrespondingtotheeportedcondensertemperaturerise.Therefore,itisbelievedthatnoadverseenvironmentalimpacthasresultedfromthisevent.Also,thedischargeareathermographrecorderswhicharelocatedinthevicinityofthehotspothaveshownnotimesatwhichthemaximumallowableinstantaneoustemperatureinthehotspotwasexceeded.B.CauseTheconditionsofthecirculatingwatersystemwhichcausedtheseeventshavebeendescribedinthepreviousR.O.-reportswhichwerecitedinSectionAabove.C.CorrectiveActionOperationofthecondensersatgreater-than-designflowhasbeenundertakenoccasionallytohelppreventexceedingthecondenserhTlimitandcancontinueuptosomepoint.However,780'M40157 thismodeofoperationisconsideredundesirableforlongtermoperationsinceitwillaffecttheintegrityoftheAluminum-Brasscondensertubes.ByletterdatedAugust29,1978(L-78-281)werequestedthattheallowablecondenserhTbeincreasedto26'Fforaninterimperiod.Neareawaitinglicensingactiononthisrequest.Atthistime,itisplannedtoreplacetheexistingAluminum-Brasscondensertubeswithtitaniumtubesduringthecycle3refuelingoutageforSt.Lucie1,expectedtobegininApril,1979.Althoughthisisexpectedtorestoresomeoftheopera-tingmargintothesystem,suchthatthecondenserdTcanbemaintainedatorbelow24'Fforsomeperiodoftime,itdoesnotaddressanyanticipatedfuturedegradationinsystemper-formance.FPLthereforeplanstorequestapermanentmodifi-cationoftheETStoallowoperationatahighercondenserhTuponcompletionofthenecessaryenvironmentalassessments.

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