1、Designation: D5373 13D5373 14Standard 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 yea
2、r 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 () indicates an editorial change since the last revision or reapproval.1. Scope1.1 Test Method A covers the determination of carbon in the
3、 range 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 the analysis samples (7.1) of coal.1.1.1 Test Method B covers the determination of carbon in analysis samples of coal in the range of 58.0 % to 84.2 %, and carbonin analysis samples
4、 of coke in the range of 86.3 % to 95.2 %.NOTE 1The coals included in the interlaboratory study employed to derive the precision statement for this standard cover ASTM rank lignite A tolow volatile bituminous. Additional information concerning the composition of these coals appears in Annex A5. The
5、cokes used in the interlaboratorystudy employed to derive the precision statement for coke included an equal number of met cokes and pet cokes.1.2 All percentages are percent mass fractions unless otherwise noted.1.3 The values stated in SI units are to be regarded as standard. No other units of mea
6、surement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylim
7、itations prior to use.2. Referenced Documents2.1 ASTM Standards:2D346/D346M Practice for Collection and Preparation of Coke Samples for Laboratory AnalysisD2013 Practice for Preparing Coal Samples for AnalysisD3173 Test Method for Moisture in the Analysis Sample of Coal and CokeD3176 Practice for Ul
8、timate Analysis of Coal and CokeD3180 Practice for Calculating Coal and Coke Analyses from As-Determined to Different BasesD5865 Test Method for Gross Calorific Value of Coal and CokeD7582 Test Methods for Proximate Analysis of Coal and Coke by Macro Thermogravimetric Analysis2.2 ISO Standard:ISO 57
9、25-6 Accuracy (Trueness and Precision) of Measurement Methods and Results Part 6: Use in Practice of AccuracyValues33. Summary of Test Methods3.1 In Method A, carbon, hydrogen and nitrogen in coal are determined concurrently in a single instrumental procedure usinga furnace operating at temperatures
10、 in the range of 900 C to 1050C. The quantitative conversion of the carbon, hydrogen andnitrogen into their corresponding gases (CO2, H2O, and NOx) occurs during combustion of the sample at an elevated temperaturein an atmosphere of oxygen. Combustion products which can interfere with the subsequent
11、 gas analysis are removed. Oxides ofnitrogen (NOx) are reduced to N2 before detection. The carbon dioxide, water vapor and elemental nitrogen in the gas stream aredetermined by appropriate instrumental detection procedures.1 These test methods are under the jurisdiction of ASTM Committee D05 on Coal
12、 and Coke and are the direct responsibility of Subcommittee D05.21 on Methods ofAnalysis.Current edition approved Oct. 15, 2013March 1, 2014. Published November 2013March 2014. Originally approved in 1993. Last previous edition approved in 20082013as D5373 08.D5373 13. DOI: 10.1520/D5373-13.2 For re
13、ferencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from American National Standards Institute (ANSI), 25 W.
14、43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all chan
15、ges accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. Un
16、ited States13.2 In Method B, carbon in coal and coke is determined by combusting the sample in a 1350C furnace. The H2O in thecombustion gases is removed and CO2 is determined by infrared absorption.4. Significance and Use4.1 Carbon and hydrogen values can be used to determine the amount of oxygen (
17、air) required in combustion processes and forcalculation of the efficiency of combustion processes.4.2 Carbon and hydrogen determinations can be used in calculations including material balance, reactivity and yields ofproducts relevant to coal conversion processes such as gasification and liquefacti
18、on.4.3 Carbon and nitrogen values can be used in material balance calculations employed for emission accounting purposes.NOTE 2The bulk composition of coal changes at a rate that varies from coal to coal during storage. As a result using coal for calibration can yieldincorrect estimates of carbon, a
19、nd hydrogen content in particular.5. Apparatus5.1 Analytical Instrument for CHN Analysis (Method A)An instrument capable of analyzing a test portion of 6 mg or greater.It includes a furnace capable of maintaining a temperature (900C to 1050C) in the range to ensure quantitative recovery ofcarbon, hy
20、drogen and nitrogen in coal as their corresponding gases (CO2, H2O, and NOx). The combustion gases or arepresentative aliquot shall be treated to remove, separate out or convert any components that can interfere with the measurementof carbon dioxide, water vapour or nitrogen. The detection system sh
21、all include provisions for evaluating the response in a mannerthat correlates accurately with the carbon dioxide, water vapour and nitrogen present in the treated combustion gases.5.2 Analytical Instrumentation for Carbon in Coal and Coke Analysis (Method B)An instrument with a furnace capable ofmai
22、ntaining a temperature of at least 1350C at all times during the analysis. The high temperature helps ensure the quantitativerecovery of carbon from cokes. The infrared absorption detection system shall include provisions for evaluating the response ina manner that correlates accurately with the car
23、bon dioxide present in the dry combustion gases. Follow the manufacturersrecommendations for sample mass (typically 50 mg to 300 mg).5.3 BalanceA stand-alone balance or a balance integrated with the instrument, with a resolution of at least 0.1 % relative ofthe test portion mass.6. Reagents6.1 Purit
24、y of ReagentsReagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that allreagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society, wheresuch specifications are available.4 Other grades may be used
25、, provided it is first ascertained that the reagent is of sufficiently highpurity to permit its use without lessening the accuracy of the determination.6.2 Carrier Gas, as specified for the instrument by the manufacturer.6.3 Oxygen, as specified for the instrument by the manufacturer.6.4 Additional
26、Reagents, of types and qualities as specified for the instrument by the manufacturer.6.5 Calibration MaterialsCalibration materials shall be accompanied by a certificate of analysis stating the purity of thematerial. If the certificate of analysis does not provide assigned values for carbon, hydroge
27、n or nitrogen use the purity as statedon the certificate to establish carbon, hydrogen and nitrogen from the theoretical values. Store these pure substances in a desiccatorunder conditions that maintain the compounds in a dry state.6.6 Reference MaterialsCertified reference material (CRM) coal(s) pr
28、epared by a recognized authority to monitor changes ininstrument response that can be affected by constituents not present in the calibration materials (Note 3) and to verify theacceptability of nitrogen results. Coal(s) traceable to a certified reference material (CRM) coal(s) can also be used. Fol
29、low4 Reagent Chemicals, American Chemical Society Specifications , American Chemical Society, Washington, DC. For suggestions on the testing of reagents not listed bythe American Chemical Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pha
30、rmacopeia and NationalFormulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville, MD.TABLE 1 Calibration Materials and Their Theoretical Contents ofCarbon, Hydrogen and Nitrogen (Method A)Name Formula C % H % N %EDTA C10H16N2O8 41.1 5.5 9.6Phenylalanine C9H11NO2 65.4 6.7 8.5Acetanilide C8H9NO
31、 71.1 6.7 10.4BBOT C26H26N2O2S 72.5 6.1 6.5Graphite C 100.0D5373 142instructions on the reference material certificate with respect to storage of the reference material and use of assigned values. Useonly those carbon, hydrogen and nitrogen values that have an assigned uncertainty or are traceable t
32、o a value with an assigneduncertainty.NOTE 3Coal contains mineral constituents as well as acid gas forming constituents that can affect the performance of chemicals used to ensure theconsistent and uniform conversion and recovery of carbon, hydrogen and nitrogen.NOTE 4The amount of nitrogen in the m
33、ajority of coal employed for power production purposes is in the range of 0.5 % to 1.8 % . None of thecalibrants yields percent nitrogen values within the ranges expected for coal. For this reason reference material (RM) coal is used to check theacceptability of nitrogen results.7. Preparation of An
34、alysis Sample7.1 The sample shall be the analysis sample prepared to a top size of less than 250 m (60 mesh). Coal samples shall be preparedin accordance with Practice D2013. Coke samples shall be prepared in accordance with Practice D346/D346M.8. Instrument Preparation8.1 Instrument Set-UpVerify al
35、l instrument operating parameters meet the specifications in the instrument operating manual.Verify the condition and quantities of all chemicals currently in use are satisfactory for the number of samples to be analyzed. Priorto any analysis, check for and, if necessary correct any leaks in the com
36、bustion system, and the carrier gas system.8.2 Blank AnalysesPerform blank analyses to establish carbon, hydrogen and nitrogen levels in the combustion and carriergases as required by the specific method. The level of carbon, hydrogen or nitrogen in these gases shall not exceed 1 % relativeof the in
37、strument response for the lowest mass of calibration material (8.4) for each analyte. Re-determine blank analyses wheneverthe carrier gas or oxygen supplies are changed or any chemicals are renewed.8.3 ConditioningSelect a conditioning sample in the range of 75 % (or more) carbon dry basis. It is re
38、commended that themoisture content be less than 3 %. Carry out four determinations on the conditioning sample. Discard the first determination. Ifthe range of the three retained determinations for either carbon, hydrogen or nitrogen values exceed 1.2r where r is the repeatabilityof this standard, in
39、strument stability is suspect. In this case take corrective action before proceeding with calibration.8.4 CalibrationIf the instrument has been previously calibrated in accordance with Annex A1, determinations can proceedprovided the calibration is verified in accordance with Annex A2. Otherwise cal
40、ibrate the instrument as described in Annex A1.8.4.1 Calibration for Carbon in Coal and Coke at 1350C (Method B)Use pure graphite to calibrate instruments operatingat 1350C that are used for determining carbon in coal and coke analysis samples.9. Procedure9.1 Determination:9.1.1 Carry out a determin
41、ation of the moisture content of each analysis sample or each reference material coal, or both, inaccordance with Test Method D3173 or Test Methods D7582 within 48 h of the determination of carbon, hydrogen and nitrogenon each analysis sample.9.1.2 Carry out the determination by weighing out a test
42、portion of each analysis sample within a mass range recommended bythe manufacturer. Conduct determinations on consecutive test portions of an analysis sample as needed to meet quality controlrequirements.9.1.3 Verify the calibration upon completion of all test determinations and as needed to meet qu
43、ality control requirementsaccording to Annex A2.9.1.4 Prior to conducting any test determinations, upon completion of all test determinations and as needed to meet qualitycontrol requirements conduct determinations on consecutive test portions of a reference material (RM) coal (6.6). Verify theaccep
44、tability of results for the RM coal in accordance with Annex A3.NOTE 5Appendix X2 provides guidance on the selection of the mass of a test portion that will yield for a mass of carbon similar to the mid rangemass of the calibration material.10. Calculation10.1 Record the total carbon, hydrogen and n
45、itrogen as analyzed as a percentage by mass. Report the results on dry basis to thenearest 0.1 % for carbon, 0.01 % for hydrogen and to the nearest 0.01 % for nitrogen.TABLE 2 Concentrations Range and Limits for Repeatability andReproducibility for Carbon, Hydrogen, and Nitrogen in Coal(Method A)Ele
46、ment ConcentrationRange, % 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 0.15D5373 14310.2 Use the following equations for the calculation to dry basis:10.2.1 For the carbon content:Cd 5Cad3 1001002Mad(1)10.2.2
47、 For the nitrogen content:Nd 5Nad3 1001002Mad(2)10.2.3 For the hydrogen content:Hd 5Had20.11193Mad!3 1001002Mad(3)where:d = dry basis,ad = as determined (as analyzed) basis,C = content of carbon, % ,C = content of carbon, %,N = content of nitrogen, % ,N = content of nitrogen, %,H = content of hydrog
48、en, % , andH = content of hydrogen, %, andMad = moisture content of the sample as analyzed, % .Mad = moisture content of the sample as analyzed, %.11. Precision and Bias511.1 The precision data for Test Method A for the determination of carbon, hydrogen, and nitrogen in coal are shown in Table2. The
49、 precision data for Test Method B for the determination of carbon in coal and coke are shown in Table 3.11.1.1 Repeatability Limit (r)The value below which the absolute difference between two test results calculated to a dry basis(Practices D3180 and D3176) of separate and consecutive test determinations, carried out on the same sample, in the samelaboratory, by the same operator, using the same apparatus on samples taken at random from a single quantity of homogeneousmaterial, may be expected to occur with a probability of approximately 95 %.5 Sup
