1、Designation: D 5142 04Standard Test Methods forProximate Analysis of the Analysis Sample of Coal andCoke by Instrumental Procedures1This standard is issued under the fixed designation D 5142; the number immediately following the designation indicates the year oforiginal adoption or, in the case of r
2、evision, 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 These instrumental test methods cover the determinationof moisture, volatile matter, and ash, an
3、d the calculation offixed carbon in the analysis of coal and coke samples preparedin accordance with Method D 2013 and Practice D 346. Re-sults obtained through the use of the instrumental tests havebeen shown to differ from those obtained with Test MethodsD 3173, D 3174, and D 3175 on some coals an
4、d cokes. Wherea relative bias between the instrumental methods and TestMethods D 3173, D 3174, and D 3175 for proximate analysisof coal and coke are shown to exist, the instrumental resultsshall be corrected or the instrument calibrated using samples ofknown proximate analysis. Test Methods D 3173,
5、D 3174, andD 3175 shall be considered the referee test methods. Theinstrumental test methods are not applicable to thermogravi-metric analyzers using microgram size samples.1.2 The moisture value determined is used for calculatingother analytical results to a dry basis. When used in conjunc-tion wit
6、h the air dry loss moisture, as determined in accordancewith Method D 2013, Test Method D 3302, or Practice D 346,the calculated total moisture can be used to convert dry basisanalytical results to the as-received basis.1.3 The result of the ash determinations can be applied inthe ultimate analysis,
7、 Practice D 3176.1.4 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 health practices and determine the applica-bility of regulatory limitations prior to us
8、e.2. Referenced Documents2.1 ASTM Standards:2D 121 Terminology of Coal and CokeD 346 Practice for Collection and Preparation of CokeSamples for Laboratory AnalysisD 1757 Test Method for Sulfate Sulfur in Ash from Coaland CokeD 2013 Practice for Preparing Coal Samples for AnalysisD 3173 Test Method f
9、or Moisture in the Analysis Sample ofCoal and CokeD 3174 Test Method for Ash in the Analysis Sample of Coaland Coke from CoalD 3175 Test Method for Volatile Matter in the AnalysisSample of Coal and CokeD 3176 Practice for Ultimate Analysis of Coal and CokeD 3180 Practice for Calculating Coal and Cok
10、e Analysesfrom As-Determined to Different BasesD 3302 Test Method for Total Moisture in Coal3. Terminology3.1 For definitions of terms used in this test method, refer toTerminology D 121.4. Summary of Test Methods4.1 Moisture is determined by establishing the loss in massof the analysis specimen of
11、coal or coke when heated underrigidly controlled conditions of temperature, time, atmosphere,specimen mass, and equipment specifications.4.2 Volatile matter is determined by measuring the loss inmass of the moist or dried analysis specimen of coal or cokewhen heated under rigidly controlled conditio
12、ns. If appropriate,the measured mass loss establishes the volatile matter aftercorrecting for the moisture content.4.3 Ash is determined by measuring the mass of the residueremaining after burning the coal or coke specimen underrigidly controlled conditions of specimen mass, temperature,time, atmosp
13、here, and equipment specifications.4.4 In these test methods, moisture, volatile matter, and ashmay be determined sequentially in a single instrumentalprocedure. With some systems, the procedure consists ofsimply placing a specimen in the microprocessor-controlledinstrument and initiating the automa
14、tic process of analyzing thespecimen.4.5 In other systems, the analytical process is manuallycontrolled, although the instruments may have microprocessorsto assist in controlling conditions of the instrument and for1These test methods are under the jurisdiction of ASTM Committee D05 on Coaland Coke
15、and are the direct responsibility of Subcommittee D05.21 on Methods ofAnalysis.Current edition approved July 1, 2004. Published July 2004.Orginally approved in 1990. Last previous edition approved in 2002 asD 514202ae1.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact A
16、STM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.calculations. The actual an
17、alytical process can vary frominstrument to instrument, but the overall process shall providefor the determination of moisture, volatile matter, and ash asspecified in 4.1, 4.2, and 4.3.4.6 Different procedures are described to permit conformitywith differences in instrument design and for differenc
18、es insample behavior.4.7 Where a relative bias between these test methods andother ASTM test methods for the proximate analysis of coaland coke has been shown to exist (12.2.1), the instrument usedin these test methods must be calibrated using specimens ofknown composition covering the range of para
19、meters beingdetermined.5. Significance and Use5.1 Moisture, as determined by the instrumental testmethod, is used for calculating other analytical results to amoisture-free basis using procedures in Practice D 3180. Mois-ture percent determined by this test method may be used inconjunction with the
20、air-dry moisture loss determined inMethod D 2013 and Test Method D 3302 to determine totalmoisture in coal. Total moisture is used for calculating otheranalytical results to an as-received basis using Practice D 3180.5.2 Ash yield, as determined by this test method, is theresidue remaining after bur
21、ning the coal and coke samples.5.3 Volatile matter yield, when determined as herein de-scribed, may be used to (1) establish the rank of coals, (2)indicate coke yield on carbonization, (3) provide the basis forpurchasing and selling, or (4) establish burning characteristics.5.4 Fixed carbon is a cal
22、culated value. It is the differencebetween 100 and the sum of the percent moisture, ash, andvolatile matter. All percents shall be on the moisture referencebase.5.5 Moisture, ash, volatile matter, and fixed carbon percentsconstitute the proximate analysis of coal and coke.NOTE 1The ash obtained diff
23、ers in composition and amount from themineral constituents present in the original coal. Incineration causes anexpulsion of all water, the loss of carbon dioxide from carbonates, theconversion of iron pyrite into iron oxides and sulfur oxides, and otherchemical reactions. Ash yield, as determined by
24、 this test method, candiffer from the amount of ash produced in furnace operations or othercombustion systems because incineration conditions influence the chem-istry and amount of ash.6. Apparatus6.1 Furnace or OvenThe primary apparatus shall consistof a furnace or oven with a cavity large enough t
25、o acceptcrucibles containing the specimens. The furnace or oven shallbe constructed so the cavity is surrounded by a suitablerefactory and insulated so as to develop a uniform temperaturein all parts of the cavity but with a minimum free space. Thefurnace shall be capable of being heated rapidly at
26、a rate of50C/min from ambient to 950C.6.1.1 The temperatures within the cavity shall be monitoredand maintained at values that are specific to each of thedeterminations. Temperatures, as measured in crucibles locatedthroughout the cavity shall be maintained within the followinglimits:Temperature, CD
27、etermination of min maxMoisture 104 110Ash-coal 700 750Ash-coke 900 950Volatile matter 930 9706.1.2 Provisions shall be made to introduce a sweep gas ora reactant gas, and to remove products of drying, devolatiliza-tion, or combustion. Gases and acceptable flow rates for thedifferent determinations
28、are as follows:Determination of GasFlow Rate, FurnaceVolume per MinuteMoisture nitrogen or air 24Ash oxygen 0.40.8Aair 24Volatile matter nitrogen 24AThis oxygen flow is chemically equivalent to 2 to 4 volume changes of air perminute.6.2 Crucibles, with covers, of a convenient form that allowsthe moi
29、sture and volatile matter, or moisture and ash, or allthree determinations to be made on the same specimen, shall beused. The crucibles may be made of fused silica with self-sealing covers that have ground glass seals or of porcelain withself-sealing covers. The covers shall allow the rapid escape o
30、fgases during the determination of volatile matter. All cruciblesused shall have the dimensions specified by the instrumentmanufacturer.6.3 Balance, sensitive to 0.1 mg. The balance may be aninternal balance and an integral part of the instrument used fordetermining the moisture, volatile matter, an
31、d ash, or it may bea separate piece of apparatus that may not be interfaced withthe instrument.6.4 The instrumental system in its entirety shall be operatedin strict accordance with the manufacturers operating instruc-tions.6.5 Venting EquipmentCombustion and volatile gasesevolved during the test pr
32、ocedures shall be vented from thelaboratory and suitable venting equipment shall be installed inthe vicinity of the apparatus.7. Analysis Sample7.1 Obtain the sample for coal in accordance with MethodD 2013 and the sample for coke in accordance with PracticeD 346. Obtain the analysis sample by pulve
33、rizing the materialto a fineness to pass the 250-m (No. 60) sieve.8. Reagents and Materials8.1 Dry GasNitrogen (99.5 % purity) or air, dried to amoisture content of 1.9 mg/L or less (dew point 10C or less)to be used to purge the drying oven. Any desiccant or dryingmethod capable of achieving this de
34、gree of dryness is suitable.(See Reagent section of Test Method D 3173.)9. Procedure9.1 Some instruments allow for the determination of mois-ture, volatile matter, and ash in sequence using the samespecimen. Alternatively, some instruments, or components ofthe instruments, may be used to carry out s
35、eparate determina-tions of moisture, volatile matter, or ash using separatespecimens of coal or coke.D51420429.2 Heat new crucibles and covers (see 9.2.1) for use inthese test methods under the conditions of the test and coolbefore use. For each test, weigh a prepared crucible (Note 2).Add approxima
36、tely1gofcoal or coke to the crucible and thenweigh the crucible and specimen. Make all weighings to thenearest 0.1 mg. Transfer the specimen from the sample bottleto the crucible quickly to minimize the exposure of thespecimen to the atmosphere during the weighing process. Usecrucible covers to prot
37、ect the specimen before and after themoisture determination. Use crucible covers during the deter-mination of the volatile matter. Weigh the cover with thecrucible and specimen for this test.9.2.1 The cover shall fit closely enough so that the carbondeposit from bituminous, subbituminous, and lignit
38、ic coalsdoes not burn away from the under side of the cover.NOTE 2In microprocessor-controlled instruments, the specimenweights are recorded by the microprocessor and retained for furthercalculations. In instruments with internal balances, or with those inter-faced to a balance, these weights are au
39、tomatically recorded. For someinstruments without these features, the specimen weights may be enteredmanually into the microprocessor memory.9.3 Moisture Determination:9.3.1 For moisture determinations, heat the weighedsamples in crucibles without the covers in the drying oven at104 to 110C. Various
40、 modes of operation are possible depend-ing on the instrument used and the manner in which thedetermination is completed.9.3.2 Automated instruments with an internal balance thatcan weigh the specimen repeatedly during the determinationcan be programmed to terminate the test when the specimensand cr
41、ucibles have reached a constant weight. Typically,crucibles are weighed automatically at 3-min intervals, and theanalysis is complete when two successive weighings agreewithin the plateau deviation specified for the instrument. Usenitrogen with a purity 99.5 % and a moisture content of 1.9mg/L or le
42、ss (dew point of 10C or less) as the drying gas inthe oven (see 8.1). Some models of this type of instrument alsoallow for moisture determination by heating the specimen for1 h at the prescribed temperature limits.9.3.3 For moisture determinations using instruments that donot have an internal balanc
43、e, weigh the specimens and placethe specimens and crucibles without covers, in the preheatedoven (104 to 110C) through which passes a current ofpreheated air. Dry the preheated air to a moisture content of 1.9mg/L or less (dew point 10C or less). Close the oven quicklyand heat for 1 h. Then remove t
44、he specimen crucibles, coverquickly, allow to cool to ambient temperature in a desiccator,and weigh as soon as possible.9.3.3.1 Air with a moisture content of 1.9 mg/L or less (dewpoint 10C or less) may be substituted for nitrogen in themoisture and ash analysis, but nitrogen shall always be used in
45、the volatile matter determination.9.4 Volatile Matter Determination:9.4.1 Volatile matter determinations may be made using thespecimens from the moisture determinations. An alternativemethod is to weigh 1 g (to the nearest 0.1 mg) of analysissample in a preweighed crucible with self-sealing cover. P
46、lacethe crucibles in the furnace which is heated at a rate of50C/min to 950 6 20C and hold at this temperature for 7 min(see 9.2.1 and Note 3). The furnace shall have an inertatmosphere, preferably nitrogen. After cooling in a desiccator,weigh the crucibles with the specimens and covers.9.4.2 For in
47、struments with an internal balance, the instru-ment automatically weighs the crucibles, specimens, andself-sealing covers at the beginning of the analysis. Theinstrument will then make weighings at regular intervals whilethe temperature of the furnace is raised at a rate of 50C/min to950 6 20C and h
48、eld for 7 min. The instrument uses theweight of the specimen at the end of the 7-min period in thecalculation of the volatile matter.9.4.3 For instruments without an internal balance, weigh thecrucibles, specimens, and covers and then place them in thefurnace. Raise the temperature of the furnace at
49、 a rate of50C/min to 950 6 20C and hold for 7 min. Then remove thecrucibles from the furnace, without disturbing the covers, andallow to cool to ambient temperature in a desiccator. Weigh thecrucibles and covers as soon as possible.NOTE 3Warning: With some strongly caking low-volatile andmedium-volatile bituminous coals, the coke button may explode as aresult of the rapid liberation of volatile matter within the button. This isusually designated as popping. Such popping may blow the lid off thecrucible and cause mechanical losses of the coked material. Wh
