1、Designation: D5373 141Standard 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、015.1. 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 Test Method B covers the determination of carbon inanalysis samples of co
4、al 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 ASTM rank ligniteA to low volatile bituminous. Additional information con
5、cerning 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 percent mass fractions unless other-wise noted.1.3 The values stated in
6、 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 theresponsibility of the user of this standard to establish appro-priate safety and heal
7、th 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 Practice for Preparing Coal Samples for AnalysisD3173 Test Method for Moistur
8、e 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 of Coal andCokeD7582 Test Methods for Proximate Analysis of Coal andCoke
9、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, hydrogen and nitrogen in coal aredetermined concurrently in a single instr
10、umental 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 of the sample at anelevated temperature in an atmosphere of oxygen. Com
11、bustionproducts 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 determined by appropriateinstrumental detection procedures.3.2 In Method B, carbo
12、n in coal and coke is determined bycombusting the sample in a 1350C furnace. The H2Ointhecombustion gases is removed and CO2is determined byinfrared absorption.4. Significance and Use4.1 Carbon and hydrogen values can be used to determinethe amount of oxygen (air) required in combustion processesand
13、 for calculation of the efficiency of combustion processes.1These test methods are under the jurisdiction ofASTM Committee D05 on Coaland Coke and are the direct responsibility of Subcommittee D05.21 on Methods ofAnalysis.Current edition approved March 1, 2014. Published March 2014. Originallyapprov
14、ed in 1993. Last previous edition approved in 2013 as D5373 13. DOI:10.1520/D5373-13.2For 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
15、page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.2 Carbon and hydrogen determinati
16、ons 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 materialbalance calculations employed for emission accounting pur-poses.NOTE 2The bul
17、k 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 Instrument for CHN Analysis (MethodA)An instrument capable of analyzing a
18、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,H2O, and NOx). The combus-tion gases or a representative aliquot shall be
19、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 that correlates accurately with thecarbon dioxide, water vapour and nitroge
20、n 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 analysis. The high temperature helps ensurethe quantitative recovery of carb
21、on 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 manufacturers recommendations for sample mass (typi-cally 50 mg to 300 mg).5.3 Bal
22、anceA 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. Unless otherwise indicated, it is intended thatall reagents shall conform to
23、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 high purity to permit its use without lessening theaccuracy of the determ
24、ination.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 manufacturer.6.5 Calibration MaterialsCalibration materials shall beaccom
25、panied 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 carbon, hydrogen andnitrogen from the theoretical values. Store these pure su
26、b-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 that can be affected by con-stituents not present in the calibration mater
27、ials (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 storage of the reference material and use of assignedvalues. Use only those car
28、bon, 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 performance of chemicals used to ensurethe consistent and uniform conversion
29、 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 within the ranges expected forcoal. For this reason reference material (RM
30、) 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 accordance with Practice D2013. Coke samplesshall be prepared in accordance w
31、ith 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 chemicalscurrently in use are satisfactory for the number of samples to beanalyzed.
32、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. For suggestions on the testing of reagents notlisted by the American Chemic
33、al 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 Materials and Their Theoretical Contents ofCarbon, Hydrogen and Nitrogen (M
34、ethod 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 14128.2 Blank AnalysesPerform blank analyses to establishcarbon, hydrogen and nitrogen levels in the combustion andcarrier g
35、ases 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-determine blankanalyses whenever the carrier gas or oxygen supplies arechange
36、d 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 conditioning sample. Discard the first determina-tion. If the range of the th
37、ree 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 calibra-tion.8.4 CalibrationIf the instrument has been previously cali-brated
38、 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 at 1350C(Method B)Use pure graphite to calibrate instruments oper-ating at
39、 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,in accordance with Test Method D3173 or Test Methods D7582within 48 h of
40、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 determinations onconsecutive test portions of an analysis sample as needed t
41、omeet 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 determinations, uponcompletion of all test determinations and as needed to meetqualit
42、y 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 guidance on the selection of the massof a test portion that will yield for a
43、 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 % for carbon, 0.01 % for hydrogen andto the nearest 0.01 % for nitrogen.10
44、.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! 3100100 2 Mad(3)where:d = dry basis,ad = as determined (as analyzed) basis
45、,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 carbon, hydrogen, and nitrogen in coal are shown inTable 2. The precision
46、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 (Practices D3180 and D3176) of separate and consecutivetest determinations, carried
47、 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 approximately 95 %.11.1.2 Reproducibility Limit (R)The value below whichthe absolute
48、 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 Report RR:D05-1034 and RR:D05-1046.TABLE 2 Concentrations Range and Limits
49、for Repeatability andReproducibility for Carbon, Hydrogen, and Nitrogen in Coal(Method A)ElementConcentrationRange, %RepeatabilityLimit, r %Reproducibility Limit,R %Carbon 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, r %ReproducibilityLimit, R %Carbon in Coke 86.3 to 95.4 0.87 1.68Carbon in Coal 57.7 to 84.0 0.55 2.31
