Designation:D2186–05AnAmericanNationalStandardStandardTestMethodsforDeposit-FormingImpuritiesinSteam1ThisstandardisissuedunderthefixeddesignationD2186;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thesetestmethodscoverthedeterminationoftheamountofdeposit-formingimpuritiesinsteam.Determinationsaremadeoncondensedsteamsamplesinalltestmethods.TestMethodsA,B,andCgiveameasureoftheamountoftotaldeposit-formingmaterialpresent;TestMethodDdealswithspecialconstituentsthatmaybepresent.Specialprecautionsandequipment,calculationprocedures,andrangesofapplica-bilityaredescribed.Thefollowingtestmethodsareincluded:SectionsTestMethodA(GravimetricorEvaporative)6to12TestMethodB(ElectricalConductivity)13to19TestMethodC(SodiumTracer)20to26TestMethodD(SilicaandMetals)27to301.2TestMethodAisapplicablefordeterminingtotaldissolvedandsuspendedsolidsinconcentrationsnormallynotlessthan0.4mg/L(ppm).Itisapplicableonlytolong-timesteady-stateconditionsandisnotapplicablefortransients.1.3TestMethodBwillmeasureminimumimpurityconcen-trationsvaryingfrom3mg/L(ppm)downtoatleast0.005mg/L(ppm),dependingonthemeansforremovingdissolvedgasesfromthesteamcondensate.Themeansforremovingdissolvedgasesalsoaffectsthestoragecapacityofsteamcondensateinthesystemand,thus,affectstheresponseofthesystemtotransients.1.4Becauseofthehighsensitivityofmethodsformeasur-ingsodiuminsteamcondensate,TestMethodCprovidesthemostsensitivemeasureofimpuritycontentforsamplesinwhichsodiumisanappreciablepercentageoftheimpuritiespresent.Concentrationsaslowas4.0µg/L(ppb)canbedetectedbyinductivelycoupledplasmaatomicemissionspec-troscopy,0.2µg/L(ppb)byatomicabsorptionspectrophotom-etry,0.1µg/L(ppb)bygraphitefurnaceatomicabsorptionspectroscopy,andaslowas0.5µg/L(ppb)bysodiumionelectrode.Theapparatuscanbedesignedwithlowvolume,and...
