1、Designation:D4239101Designation: D4239 11Standard Test Method forSulfur in the Analysis Sample of Coal and Coke Using High-Temperature Tube Furnace Combustion1This standard is issued under the fixed designation D4239; the number immediately following the designation indicates the year oforiginal ado
2、ption 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.This standard has been approved for use by agencies of the Department of Defense.1N
3、OTEThe title of Table 1 was editorially corrected in August 2010.1. Scope1.1 This test method covers the determination of sulfur in samples of coal or coke by high-temperature tube furnace combustion.1.2 When automated equipment is used the procedure can be classified as an instrumental method.1.3 T
4、he values stated in SI units are to be regarded as standard. No other units of measurement 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 approp
5、riate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D346 Practice for Collection and Preparation of Coke Samples for Laboratory AnalysisD2013 Practice for Preparing Coal Samples for AnalysisD3173 Test Meth
6、od for Moisture in the Analysis Sample of Coal and CokeD3176 Practice for Ultimate Analysis of Coal and CokeD3180 Practice for Calculating Coal and Coke Analyses from As-Determined to Different BasesD7448 Practice for Establishing the Competence of Laboratories UsingASTM Procedures in the Sampling a
7、ndAnalysis of Coaland CokeD7582 Test Methods for Proximate Analysis of Coal and Coke by Macro Thermogravimetric Analysis Test Methods forProximate Analysis of Coal and Coke by Macro Thermogravimetric AnalysisE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test M
8、ethod2.2 ISO Standard:3ISO 11722 Solid Mineral Fuels-Hard Coal Determination of Moisture in the general analysis test sample by drying in nitrogen3. Summary of Test Method3.1 Combustion Method with Infrared Absorption DetectionA weighed test portion of sample is burned in a tube furnace ata minimum
9、operating temperature of 1350C in a stream of oxygen. During combustion at temperatures above 1350 C, the sulfurand sulfur compounds contained in the sample are decomposed and oxidized almost exclusively to gaseous sulfur dioxide, SO2.Moisture and particulates are removed from the gas by filters. Th
10、e gas stream is passed through a cell in which sulfur dioxide ismeasured by an infrared (IR) absorption detector. Sulfur dioxide absorbs IR energy at a precise wavelength within the IR spectrum.Energy is absorbed as the gas passes through the cell body in which the IR energy is being transmitted: th
11、us, at the detector, lessenergy is received.All other IR energy is eliminated from reaching the detector by a precise wavelength filter. Thus, the absorptionof IR energy can be attributed only to sulfur dioxide whose concentration is proportional to the change in energy at the detector.One cell is u
12、sed as both a reference and a measurement chamber. Total sulfur as sulfur dioxide is detected on a continuous basis.1This test method is under the jurisdiction of ASTM Committee D05 on Coal and Coke and is the direct responsibility of Subcommittee D05.21 on Methods of Analysis.Current edition approv
13、ed May 1, 2010. Published July 2010. Originally approved in 1983. Last previous edition approved in 2008 as D423908. DOI: 10.1520/D4239-10.Current edition approved April 1, 2011. Published April 2011. Originally approved in 1983. Last previous edition approved in 2010 as D4239 101. DOI:10.1520/D4239
14、-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3Available from International Organization for Standard
15、ization (ISO), 1, ch. de la Voie-Creuse, Case postale 56, CH-1211, Geneva 20, Switzerland, http:/www.iso.ch.1This 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 t
16、echnically possible to adequately depict all changes 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,
17、PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Significance and Use4.1 Sulfur is part of the ultimate analysis of coal and coke.4.2 Results of the sulfur analysis are used for evaluation of coal preparation and cleaning, evaluation of potential sulfuremissions from coal and coke com
18、bustion or conversion processes, and evaluation of coal and coke quality in relation to contractspecifications, as well as for scientific purposes.4.3 The competency of laboratories with respect to use of this standard can be established through reference to Practice D7448.5. Sample5.1 Pulverize the
19、 sample to pass No. 60 (250-m) sieve and mix thoroughly in accordance with Practice D2013 or PracticeD346.5.2 Analyze a separate portion of the analysis sample for moisture content in accordance with Test Method D3173, or D7582or ISO 11722 for calculations to other than the as-determined basis.5.3 P
20、rocedures for calculating as-determined sulfur values obtained from the analysis sample to other bases are described inPractices D3176 and D3180.6. Apparatus6.1 Measurement ApparatusEquipped to combust the sample as described in 3.1 (See Fig. 1).6.2 Tube FurnaceCapable of heating the hot zone of the
21、 combustion tube (6.3) to at least 1350C. It is normally heatedelectrically using resistance rods, a resistance wire, or molybdenum disilicide elements. Specific dimensions can vary withmanufacturers design.6.3 Combustion TubeMade of mullite, porcelain, or zircon with provisions for routing the gass
22、es produced by combustionthrough the infrared cell.6.4 Sample Combustion Boats, made of iron-free material and of a convenient size suitable for the dimensions of the combustiontube.6.5 Boat PullerWhere required, a rod of a heat-resistant material with a bent or disk end to insert and remove boats f
23、rom thecombustion tube.7. Reagents7.1 Purity of ReagentsUse reagent grade chemicals in all tests. Unless otherwise indicated, it is intended that all reagentsconform to the specifications of the Committee onAvailable Reagents of theAmerican Chemical Society, where such specificationsFIG. 1 Apparatus
24、 for the Determination of Sulfur by the Infrared Detection MethodD4239 112are available.4Other grades can be used, provided it is first ascertained the reagent is of sufficiently high purity to permit its usewithout lessening the accuracy of the determination.7.2 Magnesium Perchlorate(WarningMagnesi
25、um perchlorate is a strong oxidizing agent. Do not regenerate theabsorbent. Do not allow contact with organic materials or reducing agents.)7.3 Oxygen, 99.5 % PureCompressed gas contained in a cylinder equipped with a suitable pressure regulator and a needlevalve to control gas flow. (WarningPure ox
26、ygen vigorously accelerates combustion. Verify all regulators, lines, and valves arefree of grease and oil.)7.4 Reference Materials, Reference Material (RM)that are coal(s) or coke(s) prepared by a national metrology body. Othermaterials that are coal(s) or coke(s) with documented traceability to re
27、ference material (CRM) coal(s) or coke(s) prepared by anational metrology body can also be used. Only use material(s) with an assigned value and assigned uncertainty for sulfur. Theuncertainty expressed as the confidence interval of the assigned value shall be less than the repeatability specified i
28、n the appropriatesection on Precision and Bias of this test method.7.4.1 To minimize problems with instrument calibration or calibration verification mix all reference material before removingthe test portion from the container. Do not use the reference material for calibration or calibration verifi
29、cation when less than 2g remain in the container. The remaining material can be used for instrument conditioning.8. Procedure8.1 Instrument PreparationPerform apparatus set up system checks in accordance with manufacturers instructions.8.1.1 Balance CalibrationCalibrate the instrument balance in acc
30、ordance with manufacturers instructions.8.2 Calibration of the Infrared Detection SystemCIf the instrument has been previously calibrated in accordance with thesection on instrument calibration proceed to the Analysis Procedure otherwise carry out a calibration as specified in the sectionon instrume
31、nt calibration.8.2.1 Select reference materials (7.4), in the range of the samples to be analyzed. Use at least three such reference materials,for each range of sulfur values to be tested. Select one reference material containing at least as much sulfur as the highest levelof sulfur expected. Select
32、 two additional reference materials, one approximately at the mid-point of the range and one below thelowest level of sulfur expected.8.2.1.1 Use a mass of material recommended by the apparatus manufacturer to carry out a minimum of three determinationsto condition the equipment before calibration.
33、Use a material with a sulfur value near the mid point of the expected calibrationrange.8.2.1.2 For each reference material employed for calibration, use the as-determined sulfur value previously calculated from thecertified dry-basis sulfur value and residual moisture determined using either Test Me
34、thods D3173 or D7582 or ISO 11722. Usea mass of material and the calibration procedure recommended by the apparatus manufacturer. Weigh to at least the nearest 1 mgand evenly spread the test portion of the reference material into the sample combustion boat (6.4). Position the sample in the hotzone o
35、f the furnace until the instrument returns to baseline as indicated according to settings recommended by the manufacturer.If the analysis time exceeds the maximum analysis time recommended by the manufacturer take corrective action as recommendedby the manufacturer.8.2.2 Calibration VerificationCarr
36、y out a minimum of three determinations to condition the equipment before calibrationverification (see 8.2.1.1). Verify the instrument calibration prior to analyzing test samples, upon completion of all test samples andas needed to meet quality control requirements. Analyze a test portion of referen
37、ce material(s) (7.4) using the apparatus conditionsemployed for instrument calibration (8.2.1). Use a mass that does not exceed the maximum mass used for instrument calibrationand with a sulfur value within the range of the instrument calibration. If the value determined for each reference material
38、employedfor verification is not within the specified uncertainty for the assigned sulfur value repeat the instrument calibration in accordancewith 8.2.1. Repeat all samples analyzed since the last successful calibration verification.8.3 Analysis ProcedureSet up the apparatus (see 8.1) and verify the
39、 calibration (see 8.2.2).8.3.1 1 Raise the furnace temperature as recommended by the manufacturer to at least 1350C. Weigh a mass of the sample toat least the nearest 1 mg and not exceeding the maximum mass of reference material(s) used for calibration. Analyze the test4Reagent Chemicals, American C
40、hemical 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 Pharmacopeia and NationalFormulary, U
41、.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.TABLE 1 Repeatability and Reproducibility for Sulfur in 250 m(No.60) CoalRange Repeatability Limit (r) Reproducibility Limit (R)Range, % Repeatability Limit (r) Reproducibility Limit (R)0.285.61 0.02 + 0.03 XA0.02 + 0.09 XACoal 0.285.61 0.02 +
42、 0.03 XA0.02 + 0.09 XACoke 0.520.84 0.02 0.08 X XAw Where X is the average of two single test results.D4239 113samples using the apparatus conditions employed for calibration (8.2.1).8.3.2 When the analysis is complete, the instrument indicates the sulfur value.9. Calculation to Other Bases9.1 The p
43、ercent sulfur value obtained is on an as-determined basis.9.2 Procedures for converting the as-determined value to other bases are described in Practices D3176 and D3180.10. Precision and Bias10.1 Precision-250 m (No. 60) Samples5The precision of this method for the determination of Sulfur in the 60
44、 mesh sampleof coal and coke is shown in Table 1. The precision is characterized by repeatability (Sr, r) and reproducibility (SR, R) is describedin Table A1.1 and Table A1.2 in the Annex A1.10.1.1 Repeatability Limit (r)-the value below which the absolute difference between two test results calcula
45、ted to a dry basis(Practice D3180) of separate and consecutive test determinations, carried out on the same sample in the same laboratory by thesame operator using the same apparatus on samples taken at random from a single quantity of homogeneous material, may beexpected to occur with a probability
46、 of approximately 95%.10.1.2 Reproducibility Limit (R)the value below which the absolute difference between two test results calculated to a drybasis (Practice D3180) carried out in different laboratories using samples taken at random from a single quantity of material thatis as homogeneous as possi
47、ble, may be expected to occur with a probability of approximately 95%.10.2 BiasBias is minimized when reference material(s) are employed to calibrate the instrument.ANNEXA1. Precision StatisticsA1.1 The precision of this test method, characterized by repeatability (Sr, r) and reproducibility (SR, R)
48、 has been determinedfor the following materials as listed in Table A1.1.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of
49、 any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you
