1、Designation:D451916Standard Test Method forOn-Line Determination of Anions and Carbon Dioxide inHigh Purity Water by Cation Exchange and Degassed CationConductivity1This standard is issued under the fixed designation D4519;the number immediately following the designation indicates the year oforigina
2、l adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This on-line test method includes hydrogen exchangeand degassing by heati
3、ng or gas stripping and provides meansfor determining anions(such as Cl,SO4,NO3,and F)atlevels as low as 2 g/L(2 ppb)and carbon dioxide at the levelof 0.01 to 10 mg/L(ppm)at 25C in high purity water and insteam and water samples in power plants by measuringelectrical conductivity.1.2 The conductivit
4、y of all anions(except OH)is deter-mined and not the conductivity of an individual anion if morethan one is present.If only one anion is present(such as ClorSO4),reference to Section 4,Table 1 and Table 2 or Figs.1-3 provides the chloride or sulfate and CO2concentration.1.3 This test method has been
5、 improved in accuracy byusing a modern microprocessor instrument for conductivityand temperature measurement and appropriate temperaturecompensation algorithms for compensation,by using finalsample cooling to 25C,or both.1.4 The values stated in either SI units or inch-pound unitsare to be regarded
6、separately as standard.The values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues from the two systems may result in non-conformancewith the standard.1.5 This standard does not purport to address all of thesafety concern
7、s,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1066 Practice for Sampling SteamD1125 Test Me
8、thods for Electrical Conductivity and Resis-tivity of WaterD1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on WaterD3370 Practices for Sampling Water from Closed Conduits3.Termin
9、ology3.1 Definitions:3.1.1 For definitions of terms used in this standard,refer toTest Methods D1125 and Terminology D1129.4.Summary of Test Method4.1 This test method measures the anion concentration(suchas Cland SO4)by measuring the electrical conductivity ofthe anions after passing the sample thr
10、ough a cation exchangerin the hydrogen form,then through a degasifier.Passagethrough the cation resin replaces cations(including ammoniaand other amines)in the water with hydrogen ions.Thiseliminates interference in the measurement of anions.Threeconductivity cells located in the instrument provide
11、measure-ments of the influent conductivity,cation conductivity at theincoming sample temperature,and the effluent conductivityafter acidic(volatile)gas removal.The sample is then eithercooled to 25C or conductivity values are compensated to25C.While the influent conductivity measurement is notnecess
12、ary in determining the total anion conductivity,itsdetermination provides a more complete evaluation of thesample,which can also include an estimation of the amine1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct responsibility of Subcommittee D19.03 on Samp
13、ling Water andWater-Formed Deposits,Analysis of Water for Power Generation and Process Use,On-Line Water Analysis,and Surveillance of Water.Current edition approved June 1,2016.Published June 2016.Originallyapproved in 1985.Last previous edition approved in 2010 as D4519 10.DOI:10.1520/D4519-16.2For
14、 referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Co
15、nshohocken,PA 19428-2959.United States1 content.Measurement of the cation and degassed sampleconductivities are necessary in determining the composition ofthe influent(total anions and acidic gas content).Reference toTable 1 and Table 2 or Figs.1-3,or both,are then necessary tocomplete the determina
16、tions.4.2 In-depth studies provide additional background andupdated experience with the degassed cation conductivitytechnique(1).35.Significance and Use5.1 This test method can be a useful diagnostic tool inmeasuring the impurities and detecting their sources in highpurity water,boiler feed water and steam condensate of highpressure power plants,and in the process water of certainindustries requiring high purity water.5.2 The measurement of such impurities is most importantto these industries si
