1、BRITISH STANDARD BS EN 12952-12:2003 Water-tube boilers and auxiliary installations Part 12: Requirements for boiler feedwater and boiler water quality The European Standard EN 12952-12:2003 has the status of a British Standard ICS 13.060.25; 27.040 BS EN 12952-12:2003 This British Standard, was pub
2、lished under the authority of the Standards Policy and Strategy Committee on 3 October 2003 BSI 3 October 2003 ISBN 0 580 42730 7 National foreword This British Standard is the official English language version of EN 12952-12:2003. The UK participation in its preparation was entrusted to Technical C
3、ommittee PVE/2, Water-tube boilers, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be fo
4、und in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are res
5、ponsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep
6、 the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 17 and a back cover. The BSI copyright notice displayed in this document ind
7、icates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM EN1295212 September2003 ICS13.060.25;27.040 Englishversion WatertubeboilersandauxiliaryinstallationsPart12: Requirementsforboilerfeedwaterandboilerwaterq
8、uality Chaudirestubesdeauetinstallationsauxiliaires Partite12:Exigencesrelativeslaqualitdeleau dalimentationetdeleauenchaudire WasserrohrkesselundAnlagenkomponentenTeil12: AnforderungenandieSpeisewasserund Kesselwasserqualitt ThisEuropeanStandardwasapprovedbyCENon24July2003. CENmembersareboundtocomp
9、lywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteration.Uptodatelistsandbibliographicalreferencesconcernings uchnational standardsmaybeobtainedonapplicationtotheManagementCentreortoanyCENmember. ThisEuropeanSta
10、ndardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoitsownlanguageandnotifiedtotheManagementCentrehasthesamestatusasthe official versions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,CzechRepublic,D
11、enmark,Finland,France,Germany,Greece, Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Slovakia,Spain,Sweden,SwitzerlandandUn ited Kingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brus
12、sels 2003CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.EN1295212:2003EEN1295212:2003(E) 2 Contents page Foreword3 1 Scope 4 2 Normativereferences 4 3 Termsanddefinitions. .5 4 Conditioning.5 5 Requirements .6 6 Testofthechemicalcomposition 15 6.1 Ge
13、neral15 6.2 Sampling.15 6.3 Samplingpoints . 15 7 Analysis 16 7.1 General16 7.2 Visualcriteria. .16 7.3 Analysismethods 16 Bibliography 17EN1295212:2003(E) 3 Foreword Thisdocument(EN1295212:2003)hasbeenpreparedbyTechnicalCommitteeCEN/TC269,“Shellandwater tubeboilers“,thesecretariatofwhichisheldbyDIN
14、. ThisEuropeanStandardshallbegiventhestatusofanationalstandard,eitherbypublicationofanidenticaltextor byendorsement,atthelatestbyMarch2004,andconflictingnationalstandardsshallbewithdrawnatthelatestby March2004. TheEuropeanStandardEN12952concerningwatertubeboilersandauxiliaryinstallationsconsistsofth
15、efollowing Parts: Part1:General. Part2:Materialsforpressurepartsofboilersandaccessories. Part3:Designandcalculationforpressureparts. Part4:Inserviceboilerlifeexpectancycalculations. Part5:Workmanshipandconstructionofpressurepartsoftheboiler. Part6:Inspectionduringconstruction,documentationandmarking
16、ofpressurepartsoftheboiler. Part7:Requirementsforequipmentfortheboiler. Part8:Requirementsforfiringsystemsforliquidandgaseousfuelsfortheboiler. Part9:Requirementsforfiringsystemsforpulverizedsolidfuelsfortheboiler. Part10:Requirementsforsafeguardsagainstexcessivepressure. Part11:Requirementsforlimit
17、ingdevicesoftheboilerandaccessories. Part12:Requirementsforboilerfeedwaterandboilerwaterquality. Part13:Requirementsforfluegascleaningsystems. Part14:RequirementsforfluegasDENOXsystemsusingliquifiedpressurizedammoniaandammoniawater solution. Part15:Acceptancetests. Part16:Requirementsforgrateandflui
18、dizedbedfiringsystemsforsolidfuelsfortheboiler. CR12952Part17:Guidelinefortheinvolvementofaninspectionbodyindependentofthemanufacturer. AlthoughthesePartscanbeobtainedseparately,itshouldberecognizedthatthePartsareinterdependent.As such,thedesignandmanufactureofwatertubeboilersrequirestheapplicationo
19、fmorethanonePartinorderfor therequirementsofthestandardtobesatisfactorilyfulfilled. NOTE Parts4and15arenotapplicableduringthedesign,constructionandinstallationstages. AccordingtotheCEN/CENELECInternalRegulations,thenationalstandardsorganizationsofthefollowing countriesareboundtoimplementthisEuropean
20、Standard:Austria,Belgium,CzechRepublic,Denmark,Finland, France,Germany,Greece,Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal, Slovakia,Spain,Sweden,SwitzerlandandtheUnitedKingdom.EN1295212:2003(E) 4 1Scope ThisPartofthisEuropeanStandardappliestoallwatertubeboilersasdefine
21、dinEN129521whichareheatedby combustionofoneormorefuelsorbyhotgasesforthegenerationofsteamand/orhotwater. ThisPartofthisEuropeanStandardappliestothosecomponentsbetweenthefeedwaterinletandthesteamoutletof thesteamgenerator.Thequalityofthesteamproducedisoutsidethescopeofthisstandard. ThisPartofthisEuro
22、peanStandardaimstoensurethattheboilerisabletobeoperatedtominimizerisktopersonnel, theboilerandassociatedplantcomponentslocatednearit. NOTE1 ThispartofthisEuropeanStandarddoesnotaimtoachieveoptimumeconomicoperation.Forcertainpurposes,it willbemoreappropriatetooptimizethechemicalcharacteristicsinorder
23、to: increasethethermalefficiency; increasetheavailabilityandreliabilityoftheplant; increase steam purity; reducethemaintenancecostsrepair,chemicalcleaning,etc. ThisPartofthisEuropeanStandardsetsoutminimumrequirementsforthespecifictypesofwatertoreducetherisk ofcorrosion,sludgeprecipitationorformation
24、ofdepositswhichmayleadtoanydamageorotheroperating problems. NOTE2 ThisPartofthisEuropeanStandardhasbeenpreparedontheassumptionthattheuserofthisEurop eanStandard possessesasufficientknowledgeoftheconstructionandoperationoftheboileraswellasanadequateappreciationofwater andsteamchemistry. 2 Normativere
25、ferences ThisEuropeanStandardincorporates,bydatedorundatedreference,provisionsfromotherpublications.These normativereferencesarecitedattheappropriateplacesinthetext,andthepublicationsarelistedhereafter.For datedreferences,subsequentamendmentstoorrevisionsofanyofthesepublicationsapplytothisEuropean S
26、tandardonlywhenincorporatedinitbyamendmentorrevision.Forundatedreferences,thelatesteditionofthe publicationreferredtoapplies(includingamendments). EN129521:2001, WatertubeboilersandauxiliaryinstallationsPart1:General. ENISO99631, WaterqualityDeterminationofalkalinityPart 1:Determinationoftotalandcom
27、posite alkalinity(ISO99631:1994). ISO56671, WaterqualitySamplingPart1:Guidanceonthedesignofsamplingprogrammes. ISO56673, WaterqualitySamplingPart3:Guidanceonthepreservationandhandlingofsamples. ISO5814, WaterqualityDeterminationofdissolvedoxygenElectrochemicalprobemethod. ISO6059, WaterqualityDeterm
28、inationofthesumofcalciumandmagnesiumEDTAtitrimetricmethod. ISO6332, WaterqualityDeterminationofironSpectrometricmethodusing1,10phenanthroline. ISO6878, WaterqualitySpectrometricdeterminationofphosphorususingammoniummolybdate. ISO7888, WaterqualityDeterminationofelectricalconductivity. ISO8245,Waterq
29、ualityGuidelinesforthedeterminationoftotalorganiccarbon(TOC)anddissolvedorganic carbon(DOC).EN1295212:2003(E) 5 ISO8288, WaterqualityDeterminationofcobalt,nickel,copper,zinc,cadmiumandleadFlameatomic absorptionspectrometricmethods. ISO99641, WaterqualityDeterminationofsodiumandpotassiumPart1:Determi
30、nationofsodiumbyatomic absorptionspectrometry. ISO99642, WaterqualityDeterminationofsodiumandpotassiumPart2:Determinationofpotassiumby atomicabsorptionspectrometry. ISO10523, WaterqualityDeterminationofpH. 3 Termsanddefinitions ForthepurposeofthisEuropeanStandard,thetermsanddefinitionsgiveninEN1 295
31、21:2001andthefollowing termsanddefinitionsapply. 3.1 directconductivity directmeasuredconductivityofwater 3.2 acidconductivity conductivityofwater,measuredinthehydrogenionconcentrationformcontinuouslyflowthroughdownstreamofa stronglyacidiccautionexchanger 3.3 makeupwater waterwhichcompensatesforloss
32、esofwaterandsteamfromthesystem 3.4 feedwater mixtureofreturnedcondensateand/ormakeupwatersuppliedtotheboilerinlet 3.5 demineralizedfeedwater waterwithanelectrolytecontentaccordingtoanacidconductivityof0,2 S/cmandasilicacontent(SiO 2 ) 0,02mg/ l 3.6 boilerwater waterwithinanaturalorassistedcirculatio
33、nboiler 3.7 attemperatorspraywater waterforinjectiontocontrolsteamtemperature 4Conditioning Certainqualitycharacteristicsoffeedwaterandboilerwatershallbeimprovedbytreatmentwithchemicals. Thisconditioningcancontribute: tosupporttheformationofmagnetitelayersorotherprotectiveoxidelayers; tominimizecorr
34、osionbyoptimizingthepHvalue; tostabilizehardnessandtopreventorminimizescaling;EN1295212:2003(E) 6 toeffectchemicaloxygenscavenging; todevelopspecialcoatingswithprotectiveeffectbyfilmformationonmetallicsurfaces. Conventionalinorganicconditioningagentsincludee.g.sodiumandpotassiumhydroxide,sodiumphosp
35、hate,sodium sulphite,ammoniaandhydrazine. CoordinatedphosphatetreatmentcanalsobebeneficialincontrollingpHintheboilerwater. NOTE1 Theuseofsomeofthesechemicalscanberestrictedinsomecountries. However,organicbasedconditioningagentshavebeeninuseformanyyearsnow.Iforganicbasedconditioning agentsareused,the
36、quantitiesandmethodsforuseaswellasanalysismethodshallbespecifiedbythesupplierof thechemicalproducts. NOTE2 Itisimportanttorealizethatthesolubilityofsodiumphosphatedecreaseswithincreasingtemperatures.Thiscan leadtotheprecipitationofphosphatesfromoversaturatedsolution(hideoutphenomenon).Ifaboilerexhib
37、itshideouttenden cy (PO4concentrationintheboilerwaterislowerthantobeexpectedbycalculationfrominjectedquantityandconcentration factor)onlysodiumhydroxideshouldbeusedasalkalizingagent,orthemodeofoperationshouldbechangedto“Allvolatile treatment(AVT)“. 5Requirements 5.1 Thevaluesforthehighestallowableco
38、ncentrationsofanumberofimpuritiesandforthemaximumand minimumconcentrationsofchemicalagentswhichareaddedinordertominimizecorrosion,sludgeformationand deposits,shallbeinaccordancewithtables5.1to5.3andfigures5.1to5.5. NOTE Incertaincaseswhendemineralizedfeedwaterisused,oxygenmaybeappliedasaconditioning
39、agenttoreduce corrosionmainlyforoncethroughboiler.Thisfurtherlimitstheamountofimpuritiesundernormaloperationaswellasduring loadcycling.EN1295212:2003(E) 7 Table5.1Feedwaterforsteamboilersandhotwatergeneratorswithnaturalorassistedcirculation Feedwater Parameter Unit containingdissolvedsolids Feedwate
40、rand attemperator spraywater demineralized Makeupwaterfor hotwatergenerators Operatingpressure bar (=0,1MPa) 0,5to20 20to40 40to100 totalrange totalrange Appearance clear,freefromsuspendedsolids Directconductivityat25C S/cm notspecified,onlyguidevaluesforboilerwater relevant,seetable5.2 notspecified
41、,onlyguide valuesforboilerwater relevant,seetable5.2 Acidconductivityat25C a S/cm 9,2 c 9,2 9,2 9,2 d 7,0 Totalhardness(Ca+Mg) mmol/l 7,0thepHvalueofboilerwateraccordingtotable5.2shouldbeconsidered. d Forinjectionwateronlyvolatilealkalizingagentsshallbepermitted. e Atoperatingpressure60bar,TOC0,2mg/
42、 lisrecommended. h Organicsubstancesaregenerallyamixtureofseveraldifferentcompounds.Thecompositionofsuchmixturesandthebehaviouro ftheirindividualcomponentsunderthe conditionsofboileroperationaredifficulttopredict.Organicsubstancescandecomposetoformcarbonicacidorotheracidic decompositionproductswhich
43、increasethe acidconductivityandcausecorrosionordeposits.Theyalsocanleadtofoamingand/orprimingwhichshallbekeptaslowasp ossible.EN1295212:2003(E) 8 Table5.2Boilerwaterforsteamboilersandhotwatergeneratorswithnaturalorassistedcirculation Parameter Unit Boilerwaterforsteamboilersusing Boilerwater forhotwater generators Feedwatercontaining dissolvedsolids Feedwaterdemineralized acidconductivity30 S/cm directconduct
