BS 2486-1997 Recommendations for treatment of wate

|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||BRITISHSTANDARDBS2486:1997IncorporatingAmendmentNo.1ICS13.060.01;91.140.65NOCOPYINGWITHOUTBSIPERMISSIONEXCEPTASPERMITTEDBYCOPYRIGHTLAWRecommendationsforTreatmentofwaterforsteamboilersandwaterheatersLicensedcopy:PONTYPRIDDCOLLEGE,16/09/2007,UncontrolledCopy,©BSIBS2486:1997Issue2,April1998ThisBritishStandard,havingbeenpreparedunderthedirectionoftheHealthandEnvironmentSectorBoard,waspublishedundertheauthorityoftheStandardsBoardandcomesintoeffecton15February1997©BSI1998ThefollowingBSIreferencesrelatetotheworkonthisstandard:CommitteereferenceCII/62(formerlyEPC/37/8)Draftforcomment95/521422DCISBN0580262200AmendmentsissuedsincepublicationAmd.No.DateTextaffected9948April1998IndicatedbyasidelineinthemarginCommitteesresponsibleforthisBritishStandardThepreparationofthisBritishStandardwasentrustedtoSubcommitteeEPC/37/8,Treatmentofwaterforboilers,uponwhichthefollowingbodieswererepresented:AssociationofCirculatorManufacturersBritishAssociationforChemicalSpecialitiesBritishWaterChemicalIndustriesAssociationChemicalIndustriesAssociation(GOSIP)ElectricityAssociationHealthandSafetyExecutiveInstituteofDomesticHeatingandEnvironmentalEngineersInstituteofMarineEngineersInstituteofPlumbingManufacturersAssociationofRadiatorsandConvectorsLimitedPowerGenerationContractorsAssociationPGCA(BEAMALtd.)RoyalSocietyofChemistrySafetyAssessmentFederationLtd.Licensedcopy:PONTYPRIDDCOLLEGE,16/09/2007,UncontrolledCopy,©BSIIssue1,April1998BS2486:1997©BSI1998aSummaryofpagesThefollowingtableidentifiesthecurrentissueofeachpage.Issue1indicatesthatapagehasbeenintroducedforthefirsttimebyamendment.Subsequentissuenumbersindicateanupdatedpage.Verticalsideliningonreplacementpagesindicatesthemostrecentchanges(amendment,addition,deletion).PageIssuePageIssueFrontcoverInsidefrontcoverabiiiiiiiv221blankoriginaloriginal2original1234-181920-40InsidebackcoverBackcover222original2originaloriginal2Licensedcopy:PONTYPRIDDCOLLEGE,16/09/2007,UncontrolledCopy,©BSIbblankLicensedcopy:PONTYPRIDDCOLLEGE,16/09/2007,UncontrolledCopy,©BSIBS2486:1997©BSI1997iContentsPageForewordiiiSpecificationSection1.General1.1Scope11.2Objectives11.3References11.4Definitions2Section2.Waterqualityrequirementsforboilers2.1General32.2Qualityofwatersupply32.3Hotwatersystems32.4Steamgeneratingplant52.5Samplingandtesting16Section3.Externalwatertreatment3.1Introduction183.2Boilerfeedwatertreatmentoptions18Section4.Removalofgaseousimpurities4.1General204.2Physicalde-aeration204.3Chemicalde-aeration20Section5.Boilerwaterconditioning5.1General225.2Controlofconcentrationofsolidsinboilerwater225.3Preventionofcorrosion235.4Preventionandcontrolofdepositioninboilers275.5Hideout285.6Once-throughboilers285.7Methodofdosingboilerwaterconditioningchemicals28Section6.Condensatetreatmentandpurification6.1Condensatetreatment306.2Condensatecontaminationbyoil306.3Condensatepolishing31Section7.Corrosionanddepositcontrol7.1Feedwatertanks327.2Protectionoffeedsystems327.3Protectionofcondensatelines347.4Corrosioninboilers35Section8.Water-sideprotectionofidleboilers8.1General368.2Storageovernightorforafewdaysbutnotexportingsteam368.3Standbyandloadtoppingboilers368.4Storageforextendedperiods36Licensedcopy:PONTYPRIDDCOLLEGE,16/09/2007,UncontrolledCopy,©BSIBS2486:1997ii©BSI1997AnnexesA(informative)Methodsofexpressingconcentrationsofimpuritiesinwater38B(informative)Typicalanalysesoftreatedwater38C(informative)Steampurity,carryover,foamingandpriming39D(informative)Theprincipalsourcesofcontaminationrequiringcondensatepurification40Tables1Watertreatmentforhotwatersystems52Recommendedwatercharacteristicsforshellboilersupto30bar63Recommendedwatercharacteristicsforfiredwatertubeboilers84Recommendedwatercharacteristicsfornon-firedwatertubeboilers125Recommendedwatercharacteristicsoffeedwaterateconomizerinletforonce-throughboilers136Recommendedwatercharacteristicsforcoilboilers147Recommendedwatercharacteristicsforelectrodeboilers158Someneutralizingamineswiththeirdistributionratios30B.1AnalysesofwatertreatedbysystemsAtoF39Figures1Steamboilerfeedwaterpre-treatmentoptions42Maximumconcentrationsofsilicainboilerwater113Conductivityofsodiumnitratesolution174Variationintheconcentrationofdissolvedoxygeninwaterwithtemperature215Coordinatedandcongruentphosphatetreatments266Awell-designedfeedwatertank33ListofreferencesInsidebackcoverLicensedcopy:PONTYPRIDDCOLLEGE,16/09/2007,UncontrolledCopy,©BSIIssue2,April1998BS2486:1997©BSI1998iii1)OrSection35(2)(a)ofthePatentsAct1949ifapplicable.||||ForewordThisBritishStandardwaspreparedbySubcommitteeEPC/37/8.ItrevisesandsupersedesBS2486:1978,whichiswithdrawn.TheresponsibilityforthisstandardhasnowbeenallocatedtoCII/62.BS2486wasfirstpublishedin1954andlastrevisedin1978.Thisrevisionofthestandardbringsthetechnicalcontentuptodate,reflectingdevelopmentsandexperiencegainedinindustrialboilerdesignandoperationsince1978.Thescopehasbeenbroadenedtoincludewatertreatmentforelectrodeboilersorevapo