1、Designation: D5373 142Standard Test Methods forDetermination of Carbon, Hydrogen and Nitrogen inAnalysis Samples of Coal and Carbon in Analysis Samplesof Coal and Coke1This standard is issued under the fixed designation D5373; the number immediately following the designation indicates the year ofori
2、ginal 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.1NOTEUpdated research report footnote in Section 11 editorially in March 2
3、015.2NOTECorrected table headings in Tables 2 and 3 editorially in May 2016.1. Scope1.1 Test MethodAcovers the determination of carbon in therange of 54.9 % to 84.7 %, hydrogen in the range of 3.25 % to5.10 %, and nitrogen in the range of 0.57 % to 1.80 % in theanalysis samples (7.1) of coal.1.1.1 T
4、est Method B covers the determination of carbon inanalysis samples of coal in the range of 58.0 % to 84.2 %, andcarbon in analysis samples of coke in the range of 86.3 % to95.2 %.NOTE 1The coals included in the interlaboratory study employed toderive the precision statement for this standard cover A
5、STM rank ligniteA to low volatile bituminous. Additional information concerning thecomposition of these coals appears in Annex A5. The cokes used in theinterlaboratory study employed to derive the precision statement for cokeincluded an equal number of met cokes and pet cokes.1.2 All percentages are
6、 percent mass fractions unless other-wise noted.1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibilit
7、y 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:2D346/D346M Practice for Collection and Preparation ofCoke Samples for Laboratory AnalysisD2013 Pract
8、ice for Preparing Coal Samples for AnalysisD3173 Test Method for Moisture in the Analysis Sample ofCoal and CokeD3176 Practice for Ultimate Analysis of Coal and CokeD3180 Practice for Calculating Coal and Coke Analysesfrom As-Determined to Different BasesD5865 Test Method for Gross Calorific Value o
9、f Coal andCokeD7582 Test Methods for Proximate Analysis of Coal andCoke by Macro Thermogravimetric Analysis2.2 ISO Standard:ISO 5725-6 Accuracy (Trueness and Precision) of Measure-ment Methods and Results Part 6: Use in Practice ofAccuracy Values33. Summary of Test Methods3.1 In Method A, carbon, hy
10、drogen and nitrogen in coal aredetermined concurrently in a single instrumental procedureusing a furnace operating at temperatures in the range of 900C to 1050C. The quantitative conversion of the carbon,hydrogen and nitrogen into their corresponding gases (CO2,H2O, and NOx) occurs during combustion
11、 of the sample at anelevated temperature in an atmosphere of oxygen. Combustionproducts which can interfere with the subsequent gas analysisare removed. Oxides of nitrogen (NOx) are reduced to N2before detection. The carbon dioxide, water vapor and elemen-tal nitrogen in the gas stream are determine
12、d by appropriateinstrumental detection procedures.3.2 In Method B, carbon in coal and coke is determined bycombusting the sample in a 1350C furnace. The H2Ointhecombustion gases is removed and CO2is determined byinfrared absorption.1These test methods are under the jurisdiction ofASTM Committee D05
13、on Coaland Coke and are the direct responsibility of Subcommittee D05.21 on Methods ofAnalysis.Current edition approved March 1, 2014. Published March 2014. Originallyapproved in 1993. Last previous edition approved in 2013 as D5373 13. DOI:10.1520/D5373-14e2.2For referenced ASTM standards, visit th
14、e 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.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY
15、10036, http:/www.ansi.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Significance and Use4.1 Carbon and hydrogen values can be used to determinethe amount of oxygen (air) required in combustion processesand for calculation of
16、the efficiency of combustion processes.4.2 Carbon and hydrogen determinations can be used incalculations including material balance, reactivity and yields ofproducts relevant to coal conversion processes such as gasifi-cation and liquefaction.4.3 Carbon and nitrogen values can be used in materialbal
17、ance calculations employed for emission accounting pur-poses.NOTE 2The bulk composition of coal changes at a rate that variesfrom coal to coal during storage. As a result using coal for calibration canyield incorrect estimates of carbon, and hydrogen content in particular.5. Apparatus5.1 Analytical
18、Instrument for CHN Analysis (MethodA)An instrument capable of analyzing a test portion of 6 mgor greater. It includes a furnace capable of maintaining atemperature (900C to 1050C) in the range to ensure quanti-tative recovery of carbon, hydrogen and nitrogen in coal astheir corresponding gases (CO2,
19、H2O, and NOx). The combus-tion gases or a representative aliquot shall be treated to remove,separate out or convert any components that can interfere withthe measurement of carbon dioxide, water vapour or nitrogen.The detection system shall include provisions for evaluatingthe response in a manner t
20、hat correlates accurately with thecarbon dioxide, water vapour and nitrogen present in thetreated combustion gases.5.2 Analytical Instrumentation for Carbon in Coal andCoke Analysis (Method B)An instrument with a furnacecapable of maintaining a temperature of at least 1350C at alltimes during the an
21、alysis. The high temperature helps ensurethe quantitative recovery of carbon from cokes. The infraredabsorption detection system shall include provisions for evalu-ating the response in a manner that correlates accurately withthe carbon dioxide present in the dry combustion gases. Followthe manufact
22、urers recommendations for sample mass (typi-cally 50 mg to 300 mg).5.3 BalanceA stand-alone balance or a balance integratedwith the instrument, with a resolution of at least 0.1 % relativeof the test portion mass.6. Reagents6.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unl
23、ess otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.4Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently
24、 high purity to permit its use without lessening theaccuracy of the determination.6.2 Carrier Gas, as specified for the instrument by themanufacturer.6.3 Oxygen, as specified for the instrument by the manufac-turer.6.4 Additional Reagents, of types and qualities as specifiedfor the instrument by the
25、 manufacturer.6.5 Calibration MaterialsCalibration materials shall beaccompanied by a certificate of analysis stating the purity ofthe material. If the certificate of analysis does not provideassigned values for carbon, hydrogen or nitrogen use the purityas stated on the certificate to establish car
26、bon, hydrogen andnitrogen from the theoretical values. Store these pure sub-stances in a desiccator under conditions that maintain thecompounds in a dry state.6.6 Reference MaterialsCertified reference material(CRM) coal(s) prepared by a recognized authority to monitorchanges in instrument response
27、that can be affected by con-stituents not present in the calibration materials (Note 3) and toverify the acceptability of nitrogen results. Coal(s) traceable toa certified reference material (CRM) coal(s) can also be used.Follow instructions on the reference material certificate withrespect to stora
28、ge of the reference material and use of assignedvalues. Use only those carbon, hydrogen and nitrogen valuesthat have an assigned uncertainty or are traceable to a valuewith an assigned uncertainty.NOTE 3Coal contains mineral constituents as well as acid gas formingconstituents that can affect the pe
29、rformance of chemicals used to ensurethe consistent and uniform conversion and recovery of carbon, hydrogenand nitrogen.NOTE 4The amount of nitrogen in the majority of coal employed forpower production purposes is in the range of 0.5 % to 1.8 % . None of thecalibrants yields percent nitrogen values
30、within the ranges expected forcoal. For this reason reference material (RM) coal is used to check theacceptability of nitrogen results.7. Preparation of Analysis Sample7.1 The sample shall be the analysis sample prepared to atop size of less than 250 m (60 mesh). Coal samples shall beprepared in acc
31、ordance with Practice D2013. Coke samplesshall be prepared in accordance with Practice D346/D346M.8. Instrument Preparation8.1 Instrument Set-UpVerify all instrument operating pa-rameters meet the specifications in the instrument operatingmanual. Verify the condition and quantities of all chemicalsc
32、urrently in use are satisfactory for the number of samples to beanalyzed. Prior to any analysis, check for and, if necessarycorrect any leaks in the combustion system, and the carrier gassystem.4Reagent Chemicals, American Chemical Society Specifications , AmericanChemical Society, Washington, DC. F
33、or 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 Convention, Inc. (USPC), Rockville,MD.TABLE 1 Calibration M
34、aterials and Their Theoretical Contents ofCarbon, Hydrogen and Nitrogen (Method A)Name Formula C % H % N %EDTA C10H16N2O841.1 5.5 9.6Phenylalanine C9H11NO265.4 6.7 8.5Acetanilide C8H9NO 71.1 6.7 10.4BBOT C26H26N2O2S 72.5 6.1 6.5Graphite C 100.0D5373 14228.2 Blank AnalysesPerform blank analyses to es
35、tablishcarbon, hydrogen and nitrogen levels in the combustion andcarrier gases as required by the specific method. The level ofcarbon, hydrogen or nitrogen in these gases shall not exceed1 % relative of the instrument response for the lowest mass ofcalibration material (8.4) for each analyte. Re-det
36、ermine blankanalyses whenever the carrier gas or oxygen supplies arechanged or any chemicals are renewed.8.3 ConditioningSelect a conditioning sample in the rangeof 75 % (or more) carbon dry basis. It is recommended that themoisture content be less than 3 %. Carry out four determina-tions on the con
37、ditioning sample. Discard the first determina-tion. If the range of the three retained determinations for eithercarbon, hydrogen or nitrogen values exceed 1.2r where r is therepeatability of this standard, instrument stability is suspect. Inthis case take corrective action before proceeding with cal
38、ibra-tion.8.4 CalibrationIf the instrument has been previously cali-brated in accordance with Annex A1, determinations canproceed provided the calibration is verified in accordance withAnnex A2. Otherwise calibrate the instrument as described inAnnex A1.8.4.1 Calibration for Carbon in Coal and Coke
39、at 1350C(Method B)Use pure graphite to calibrate instruments oper-ating at 1350C that are used for determining carbon in coaland coke analysis samples.9. Procedure9.1 Determination:9.1.1 Carry out a determination of the moisture content ofeach analysis sample or each reference material coal, or both
40、,in accordance with Test Method D3173 or Test Methods D7582within 48 h of the determination of carbon, hydrogen andnitrogen on each analysis sample.9.1.2 Carry out the determination by weighing out a testportion of each analysis sample within a mass range recom-mended by the manufacturer. Conduct de
41、terminations onconsecutive test portions of an analysis sample as needed tomeet quality control requirements.9.1.3 Verify the calibration upon completion of all testdeterminations and as needed to meet quality control require-ments according to Annex A2.9.1.4 Prior to conducting any test determinati
42、ons, uponcompletion of all test determinations and as needed to meetquality control requirements conduct determinations on con-secutive test portions of a reference material (RM) coal (6.6).Verify the acceptability of results for the RM coal in accor-dance with Annex A3.NOTE 5Appendix X2 provides gu
43、idance on the selection of the massof a test portion that will yield for a mass of carbon similar to the midrange mass of the calibration material.10. Calculation10.1 Record the total carbon, hydrogen and nitrogen asanalyzed as a percentage by mass. Report the results on drybasis to the nearest 0.1
44、% for carbon, 0.01 % for hydrogen andto the nearest 0.01 % for nitrogen.10.2 Use the following equations for the calculation to drybasis:10.2.1 For the carbon content:Cd5 Cad3100100 2 Mad(1)10.2.2 For the nitrogen content:Nd5 Nad3100100 2 Mad(2)10.2.3 For the hydrogen content:Hd5 Had2 0.1119 3 Mad!
45、3100100 2 Mad(3)where:d = dry basis,ad = as determined (as analyzed) basis,C = content of carbon, %,N = content of nitrogen, %,H = content of hydrogen, %, andMad= moisture content of the sample as analyzed, %.11. Precision and Bias511.1 The precision data for Test Method A for the determi-nation of
46、carbon, hydrogen, and nitrogen in coal are shown inTable 2. The precision data for Test Method B for thedetermination of carbon in coal and coke are shown in Table 3.11.1.1 Repeatability Limit (r)The value below which theabsolute difference between two test results calculated to a drybasis (Practice
47、s D3180 and D3176) of separate and consecutivetest determinations, carried out on the same sample, in thesame laboratory, by the same operator, using the same appa-ratus on samples taken at random from a single quantity ofhomogeneous material, may be expected to occur with aprobability of approximat
48、ely 95 %.11.1.2 Reproducibility Limit (R)The value below whichthe absolute difference between two test results calculated to adry basis (Practices D3180 and D3176), carried out in different5Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research R
49、eport RR:D05-1034 and RR:D05-1046.TABLE 2 Concentrations Range and Limits for Repeatability andReproducibility for Carbon, Hydrogen, and Nitrogen in Coal(Method A)ElementConcentrationRange, %RepeatabilityLimit, rReproducibility Limit,RCarbon 54.9 to 84.7 0.45 1.00Hydrogen 3.25 to 5.10 0.10 0.25Nitrogen 0.57 to 1.80 0.05 0.15TABLE 3 Concentration Range and Limits for Repeatability andReproducibility for Carbon in Coal and Coke Determined Using1350C Combustion (Method B)Element ConcentrationRange, %RepeatabilityLimit, rReproducibilityLimit, RCarbon
