1、Designation: D 4519 94 (Reapproved 2005)Standard 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 D 4519; the number immediately following the designation indic
2、ates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This on-line test method includes hydrogen
3、 exchangeand degassing by boiling and provides means for determininganions (such as Cl,SO4,NO3, and F) at levels as lowas 2 g/L (2 ppb) and carbon dioxide at the level of 0.01 to 10mg/L (ppm) at 25C in high purity water and steam condensateby measuring electrical conductivity.1.2 The conductivity of
4、 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 Clor SO4), reference to Table 1 and Table 2 or Figs. 1-3provides the chloride or sulfate and CO2concentration.1.3 This test method has been improve
5、d in accuracy byusing a modern microprocessor instrument for conductivityand temperature measurement and appropriate temperaturecompensation algorithms for compensation to 25C.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsib
6、ility 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:2D 1066 Practice for Sampling SteamD 1125 Test Methods for Electrical Conductivity and Re-sistivi
7、ty of WaterD 1129 Terminology Relating to WaterD 1192 Specifications for Equipment for Sampling Waterand Steam in Closed ConduitsD 1193 Specification for Reagent WaterD 2777 Practice for Determination of Precision and Bias ofApplicable Methods of Committee D19 on WaterD 3370 Practices for Sampling W
8、ater from Closed Conduits3. Terminology3.1 DefinitionsFor definitions of terms used in this testmethod, refer to Test Methods D 1125 and TerminologyD 1129.4. Summary of Test Method4.1 This test method measures the anion concentration (suchas Cland SO4) by measuring the electrical conductivity ofthe
9、anions after passing cooled condensate or high purity waterthrough a cation exchanger in the hydrogen form, then throughan electric reboiler. Passage through the cation resin replacescations (including ammonia and amines) in the water withhydrogen ions. This eliminates interference in the measure-me
10、nt of anions. Three conductivity cells located in the instru-ment provide measurements of the influent conductivity, cationconductivity at the incoming sample temperature, and theeffluent conductivity at atmospheric boiling water temperature1This test method is under the jurisdiction of ASTM Committ
11、ee D19 on Waterand is the direct responsibility of Subcommittee D19.03 on Sampling of Water andWater-Formed Deposits, Analysis of Water for Power Generation and Process Use,On-Line Water Analysis, and Surveillance of WaterCurrent edition approved Jan. 1, 2005. Published January 2005. Originallyappro
12、ved in 1985. Last previous edition approved in 1999 as D 4519 94 (1999)e1.2For 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
13、ASTM website.TABLE 1 Increase in Conductivity of Pure Water Expressed asChloride Ion or Sulfate IonConductivity due toChloridesConcentrationChlorides (PPB)Conductivity due toSulfatesConcentrationSulfates (PPB)0.0548 0.0 0.0548 0.00.0595 1 0.0608 10.0651 2 0.0669 20.0717 3 0.0732 30.0791 4 0.0797 40.
14、0872 5 0.0862 50.0958 6 0.0929 60.1049 7 0.0997 70.1145 8 0.1066 80.1243 9 0.1137 90.1344 10 0.1208 100.2427 20 0.1969 200.3560 30 0.2780 300.4709 40 0.3616 400.5865 50 0.4455 500.7023 60 0.5320 600.8183 70 0.6181 700.9345 80 0.7044 801.0507 90 0.7909 901.1669 100 0.8775 1002.2209 200 1.7470 2005.82
15、52 500 4.362 5001Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.after acidic (volatile) gas removal. Conductivity values arethen corrected to 25C. While the influent conductivity mea-surement is not necessary in determining the total
16、 anionconductivity, its determination provides a more completeevaluation of the sample, which can also include an estimationof the amine content. Measurement of the cation and reboileffluent conductivities are necessary in determining the com-position of the influent (total anions and acidic gas con
17、tent).Reference to Table 1 and Table 2 or Figs. 1-3, or both, are thennecessary to complete the determinations.5. Significance and Use5.1 This test method can be a useful diagnostic tool inmeasuring the impurities and detecting their sources in highpurity water, the steam condensate of high pressure
18、 powerplants, and in the process water of certain industries requiringwater of the highest purity attainable.5.2 The measurement of such impurities is most importantto these industries since plant outages or product contaminationcan result from events such as condenser leakage. Also, waterquality de
19、viations can occur from condensate polishing andmakeup water equipment malfunctions.5.3 The continuous measurement and trends provided bythis test method are of particular interest and can indicate theneed for corrections in water treating or operating proceduresand equipment. The equipment for this
20、 test method can beconsidered more rugged and adaptable to installation underplant operating conditions than the more accurate laboratorymethods, such as ion chromatography and atomic absorption.6. Interferences6.1 It is important to devote particular attention to accurateflow and temperature contro
21、l as variations can cause inaccu-racies. See Annex A1, Annex A2, and Annex A3 for additionalinformation on this subject.7. Apparatus7.1 Mechanical Ion Exchanger-Degasser Instrument.7.2 Constant Head Device, for providing approximately 1.5m (5 ft) head pressure for water entering the instrument.7.3 C
22、onstant Temperature Equipment, for adjusting theinfluent temperature to 25C 6 0.5C.7.4 Conductivity Instruments and Sensors, for measuringthe conductivity of the sample to determine the concentrationof anions and carbon dioxide. Use of instruments that have aspecialized temperature compensation for
23、high purity water (to25C) based on an acid such as HCl or H2SO4is required forthis test method.7.5 Hydrogen Exchange Cartridge,158 in. inside diameter,12 in. height, containing 1 lb of 8 % cross-linked styrene-divinylbenzene, strong acid gel cation exchange resin in theH+form; U.S. standard mesh 16
24、by 50 (1190 by 297 m) maybe used. Regenerate with 1500 mL of hydrochloric acid (1 + 6)at a flow rate of 40 to 50 mL/min, followed by rinsing with 300mLofType II water at the same flow rate.Then rinse with 3500mLof Type II water at a flow rate of 100 to 150 mL/min. Rinsedown when placing in service.T
25、ABLE 2 25C Conductivity of the Sample Immediately After theCation Column, Relating to the CO2Concentration with the AnionComponent Subtracted Out (See 11.7)Conductivitys/cmCarbon Dioxideppm ppb0.0548 0 00.09 0.01 100.12 0.02 200.16 0.03 300.19 0.04 400.21 0.05 500.24 0.06 600.26 0.07 700.28 0.08 800
26、.3 0.09 900.32 0.1 1000.48 0.2 2000.61 0.3 3000.71 0.4 4000.81 0.5 5000.89 0.6 6000.97 0.7 7001.04 0.8 8001.11 0.9 9001.17 1.0 .1.69 2.0 .2.09 3.0 .2.42 4.0 .2.72 5.0 .2.98 6.0 .3.23 7.0 .3.46 8.0 .3.67 9.0 .3.88 10 .5.46 20 .FIG. 1 Chloride Ion vs. ConductivityD 4519 94 (2005)2NOTE 1The column insi
27、de diameter, resin bed height, inlet sampletemperature (11.3), and service flowrate (11.4) have been standardized toprovide comparable results. They may not be the optimum values. Theuser should realize that those parameters affect the measurement.7.6 Software to automate the determination of anions
28、 andcarbon dioxide is available.8. Reagents8.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of theAmericanChemical Society, where such specifications are available.3Other grades ma
29、y be used, provided it is first ascertained thatthe reagent is of sufficiently high purity to permit its usewithout lessening the accuracy of the determination.8.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water conformingto Specification D 119
30、3, Type II.8.3 Chloride Solution, Stock (1 mL = 0.1 mg Cl) Dis-solve in water 0.1649 g of sodium chloride (NaCl) dried toconstant weight at 105C, and dilute to 1 L in a thoroughlycleaned polyethylene flask.8.4 Chloride Solution, Standard (1.00 mL = 0.001 mg)Dilute 10.00 mL of chloride stock solution
31、 (8.3) to 1 L withwater.8.4.1 This standard chloride solution is to be used in thecalibration of the instrument if desired, or reference can bemade to the instruction booklet furnished with the instrument.8.5 Hydrochloric Acid (1 + 6)Add 100 mL concentratedHCl (sp. gr. 1.19) to 600 mL water.9. Sampl
32、ing9.1 Collect the sample in accordance with the applicableASTM standards: Practice D 1066, Specification D 1192, andPractices D 3370.10. Calibration10.1 The instrument may be calibrated by pumping solu-tions of known concentrations of Cl(in NaCl form) or3Reagent Chemicals, American Chemical Society
33、 Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmaceutical
34、 Convention, Inc. (USPC), Rockville,MD.FIG. 2 Sulfate Ion vs. ConductivityFIG. 3 Carbon Dioxide vs. ConductivityD 4519 94 (2005)3SO4(in Na2SO4form) through the instrument and observingthe conductivity increases. It may be preferred to use thecalibration charts shown in the instruction book accompany
35、ingthe instrument or in referenced articles.4 , 5, 6 , 710.2 If it is desired to calibrate the instrument using knownchloride solutions, the range of 0.001 to 0.010 mg/L (1 to 10ppb) of chloride may be covered by application of 0.2 to 2.0mL/min of the standard chloride solution (8.4.1) to the 200mL/
36、min flow by injecting the flow from a small peristalticpump to a hypodermic needle inserted in a plastic tubingconnection.11. Procedure11.1 Flush out the piping thoroughly by flow of high puritywater through the instrument before starting the flow of waterto be tested.11.2 Refer to the manufacturers
37、 instruction booklet beforestarting the instrument. Because of the nature of this measuringtechnique, it is very important to follow the manufacturersinstructions very carefully in order to achieve accurate results.SeeAnnexA1-AnnexA4 for a discussion on the effects causedby variations in operating c
38、onditions and interfering sub-stances.11.3 Connect the high purity water or condensate to betested to the instrument influent connection. This water shouldpreferably be at a temperature of 25 6 0.5C. The flow shallfirst pass through the constant head device, then into theinstrument through the hydro
39、gen ion exchanger and electricreboiler and out the reboil chamber effluent (Fig. 4 and Fig. 5).11.4 Adjust the flow through the instrument to the properflow rate (200 mL/min), or as specified by the instrument4Lane, R. W., Sollo, F. W., Neff, C. H., “Continuous Monitoring of Anions inFeedwater by El
40、ectrical Conductivity,” Illinois State Water Survey Reprint 473,Reprinted from “Water and Steam, Their Properties and Current Industrial Appli-cations,” Pergammon Press, Oxford and New York, 1980.5Electric Power Research Institute, “Monitoring Cycle Water Chemistry inFossil Plants,” EPRI GS-7556, Vo
41、l 1: Monitoring Results.6Continuous Conductivity Monitoring of Anions in High-Purity Water, ASTMSTP 742, ASTM, 1981, p. 195.7Internal report from Carl C. Scheerer, C.I.P.S., Springfield, IL, April 18, 1989.FIG. 4 Flow Diagram for Mechanical-Ion Exchanger-Degasser InstrumentD 4519 94 (2005)4manufactu
42、rer. It is important to use a constant head device inorder to maintain a stable flow rate, otherwise changes incation resin exchange efficiency may occur with changes in theflow rate.11.5 Clean up the system by maintaining the recommendedflow rate through the instrument for 24 h or longer to approac
43、ha minimum value of 0.055 S/cm reading for pure water at thefinal effluent conductivity. On restart, several hours of opera-tion may be required before this minimum conductivity valueis obtained.11.6 Refer to Table 1,orFig. 1 and Fig. 2, or both, todetermine the equivalent concentration of chloride
44、ion orsulfate ion based on the conductivity reading of the finalconductivity cell.11.7 In order to obtain the volatiles expressed as carbondioxide in Table 2, subtract the conductivity of pure water(0.055 S/cm) from the conductivity of the final effluent cell.Then deduct this value from the cation c
45、onductivity obtainedfrom the cell immediately after the cation exchange resin. Usethis adjusted conductivity value to look up the concentration ofvolatiles expressed as a concentration of carbon dioxide inTable 2,orFig. 3, or both.11.7.1 Example: Based on a final cell conductivity readingof 0.087 S/
46、cm (equivalent to 5 ppb of Clin a systempredominant in chloride ion), 0.055 S/cm is deducted for theconductivity of pure water to obtain a value of0.087 0.055 = 0.032 S/cm. Then deduct this number (0.032)from the cation conductivity (0.242 0.032) = 0.21 S/cm dueto volatiles, which corresponds to 50
47、g/L (ppb) of carbondioxide, as read from Table 2. This deduction is necessary toaccount for the anion conductivity (other than carbon dioxide)obtained in the cation conductivity measurement.FIG. 5 Mechanical-Ion Exchanger-Degasser Instrument (Larson-Lane Condensate Reboiler)D 4519 94 (2005)511.8 The
48、 service life of the cation cartridge may vary fromone month to several months depending on the amine concen-tration in the influent.12. Report12.1 Report the results as g/L Cl,orSO4, or both, andCO2as obtained fromTable 1 andTable 2,orFigs. 1-3, or both.13. Precision and Bias13.1 Since this test me
49、thod involves continuous samplingand measurement, Practice D 2777 is not applicable. Footnotes7 through 10 do show that there is excellent agreement betweenthe theoretical and measured conductivity values of ClandSO4ions in the 0 to 50 g/L (ppb) range.14. Keywords14.1 anion electrical conductivity; carbon dioxide; cationconductivity; degassed cation conductivity; electrical conduc-tivity; high purity water; reboiled conductivityANNEXES(Mandatory Information)A1. EFFECTS OF THE INFLUENT WATER TEMPERATUREA1.1 The cation res
