1、Designation: D 3174 04Standard Test Method forAsh in the Analysis Sample of Coal and Coke from Coal1This standard is issued under the fixed designation D 3174; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This test method covers the determination of th
3、e inor-ganic residue as ash in the analysis sample of coal or coke asprepared in accordance with Method D 2013 or Practice D 346.The results obtained can be applied as the ash in the proximateanalysis, Practice D 3172, and in the ultimate analysis, PracticeD 3176. For the determination of the consti
4、tuents in ash,reference is made to Test Methods D 2795 and D 3682. SeeTerminology D 121 for definition of ash.1.2 The values stated in SI units are to be regarded as thestandard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is therespons
5、ibility 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:2D 121 Terminology of Coal and CokeD 346 Practice for Collection and Preparation of CokeSamples
6、 for Laboratory AnalysisD 388 Classification of Coals by RankD 1756 Test Method for Determination as Carbon Dioxideof Carbonate Carbon in CoalD 1757 Test Method for Sulfate Sulfur in Ash from Coaland CokeD 2013 Method of Preparing Coal Samples for AnalysisD 2795 Test Methods for Analysis of Coal and
7、 Coke Ash2D 3172 Practice for Proximate Analysis of Coal and Coke2D 3173 Test Method for Moisture in theAnalysis Sample ofCoal and CokeD 3176 Practice for Ultimate Analysis of Coal and CokeD 3180 Practice for Calculating Coal and Coke Analysesfrom As-Determined to Different BasesD 3682 Test Method f
8、or Major and Minor Elements in Coaland Coke Ash by the Atomic Absorption MethodE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Summary of Test Method3.1 Ash is determined by weighing the residue remainingafter burning the coal or coke under rigidly
9、 controlled condi-tions of sample weight, temperature, time, atmosphere, andequipment specifications.4. Significance and Use4.1 Ash, as determined by this test method, is the residueremaining after burning the coal and coke. Ash obtained differsin composition from the inorganic constituents present
10、in theoriginal coal. Incineration causes an expulsion of all water, theloss of carbon dioxide from carbonates, the conversion of ironpyrites into ferric oxide, and other chemical reactions. Ash, asdetermined by this test method, will differ in amount from ashproduced in furnace operations and other
11、firing systems be-cause incineration conditions influence the chemistry andamount of the ash. References for correcting ash resultsdetermined by this test method to a mineral-matter-free basisare listed in Classification D 388, Section 8.5. Apparatus5.1 Electric Muffle Furnace for Coal or CokeFor de
12、ter-mination of ash of coal, the furnace shall have an adequate aircirculation and be capable of having its temperature regulatedat 700 to 750C. The furnace shall be equipped with atemperature indicator and means of controlling the temperaturewithin prescribed limits. Means shall be provided for mai
13、n-taining air flow at a rate of two to four changes per minute (seeFig. 1 and Fig. 2). Combustion gases shall be vented fromlaboratory. Inlet and outlet ports shall be located and arranged1This test method is under the jurisdiction of ASTM Committee D05 on Coaland Coke and is the direct responsibili
14、ty of Subcommittee D05.21 on Methods ofAnalysis.Current edition approved July 1, 2004. Published July 2004. Originally publishedas D 3174 73. Last previous edition D 3174 02e1.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. Fo
15、r 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.to distribute the air uniformly throughout the furnace areawithout the
16、 possibility of sweeping solid particles from thecapsules. The temperature over the entire working area of thefurnace floor shall be maintained within the specified tempera-ture limits.5.2 Porcelain Capsules, about 22 mm (78 in.) in depth, and44 mm (134 in.) in diameter, or similar shallow dishes or
17、platinum crucibles.5.3 Balance, sensitive to 0.1 mg.5.4 Crucible Cover, aluminum, porcelain, or similar covers.6. Temperature Calibration6.1 Place a preignited capsule with1gofsand at the centerof the working area of the furnace, and by the use of apotentiometer and thermocouple or other suitable te
18、mperaturemeasuring device, measure the temperature of the sand in thecrucible. The crucible and sand should be at temperatureequilibrium with the furnace. There should be two to four airchanges per minute moving throughout the furnace (the airflow may be measured by using a wet-test meter or equival
19、entcalibrated at standard conditions for air connected to theceramic-pipe exhaust).Adjust the furnace temperature until thepotentiometer reads 750 6 10C and then adjust or read thetemperature on the indicating pyrometer. Use this reading asthe proper setting for controlling the furnace.7. Procedure7
20、.1 The sample shall be the material pulverized to pass No.60 (250-mm) sieve in accordance with Method D 2013 orPractice D 346.7.2 Transfer approximately 1 g (weighed to the nearest 0.1mg) of the thoroughly mixed sample to a weighed capsule andcover quickly. An alternative way is to use the dried coa
21、l fromthe moisture determination in Test Method D 3173. Afterremoving the covers, place the capsule containing the samplein a cold furnace and heat gradually at such a rate that thetemperature reaches 450 to 500C in 1 h.7.3 Heat coal samples so that a final temperature of 700 to750C is reached by th
22、e end of the second hour. Heat cokesamples so that a final temperature of 950C is reached by theend of the second hour. Continue to heat at the final tempera-ture for additional 2 h (see Note 1). Remove the capsule fromthe muffle, place the cover on the capsule, cool under condi-tions to minimize mo
23、isture pickup, and weigh.NOTE 1While the 4-h incineration interval described is sufficient withmost coals to reach a condition of complete burn off, certain cokes andnonreactive coals may require additional time. If unburned carbonparticles are observed, or if duplicate results are suspect, the samp
24、lesshould be returned to the furnace for sufficient time to reach a constantweight (60.001 g). By this means, pyritic sulfur will be oxidized andexpelled before the calcite is decomposed. An ample supply of air in the(Suggested method for inducing regulated air flow through ashing furnace.)FIG. 1 Ai
25、r AspiratorD3174042muffle, “two to four changes per minute,” must be assured at all times toensure complete oxidation of the pyritic sulfur and to remove the SO2formed. The 4-h time limit may be reduced if the sample reaches aconstant weight at 700 to 750C in less than 4 h.NOTE 2Some samples may be
26、encountered that contain a highamount of carbonates (calcite) or pyrites or both. In such cases, sulfurretained as sulfates may be both unduly high and nonuniform betweenduplicate samples. In such cases, sulfate sulfur in the ash can bedetermined in accordance with Test Methods D 1757 and the valuep
27、roperly corrected. If such is done, the ash value should be reported anddesignated both as determined and corrected.8. Calculation8.1 Calculate the ash percent in the analysis sample asfollows:Ash in analysis sample, % 5 A 2 B!/C# 3 100 (1)where:A = weight of capsule, cover, and ash residue, g,B = w
28、eight of empty capsule and cover, g, andC = weight of analysis sample used, g.9. Report9.1 For reporting analyses to other than as-determined basis,refer to Practice D 3180.10. Precision and Bias10.1 Precision10.1.1 250 m (No. 60) SamplesThe precision of this testmethod for the determination of ash
29、in the analysis sample ofcoal and coke is shown in Table 1. The precision characterizedby repeatability (Sr,r)and reproducibility (SR,R)is describedin Table A1.1 in Annex A1.10.1.1.1 Repeatability Limit (r)The value below whichthe absolute difference between two test results calculated to adry basis
30、 (Practice D 3180) of separate and consecutive testdeterminations, carried out on the same sample of 250 m (No.60) coal and coke in the same laboratory, by the same operator,using the same apparatus on samples taken at random from asingle quantity of homogeneous material, may be expected tooccur wit
31、h a probability of approximately 95 %.Calibration Flowmeter with TubingAmbient AirFor calibration use only, adjust forced air valve to deliver two to four furnace volume changes per minute (at standardtemperature-pressure conditions.)NOTE 1Flowmeters are usually calibrated for one atmosphere at 70F
32、(760-mm Hg at 21.1C).(Suggested layout for calibration.)FIG. 2 Air AspiratorD317404310.1.1.2 Reproducibility Limit (R)The value below whichthe absolute difference between two test results calculated to adry basis (Practice D 3180), carried out in different laborato-ries, using samples of 250 m (No.
33、60) coal and coke taken atrandom from a single quantity of material that is as homoge-neous as possible, may be expected to occur with a probabilityof approximately 95 %.10.1.2 2.36 mm (No. 8) Samples3The precision of this testmethod for the determination of ash in the analysis sample ofcoal and cok
34、e is shown in Table 2.10.1.2.1 Repeatability Limit (r)The value below whichthe absolute difference between two test results calculated to adry basis (Practice D 3180) of separate and consecutive testdeterminations, carried out on the same sample, using the sameriffle, determined on a single test spe
35、cimen of two separate 2.36mm (No. 8) test units of coal reduced entirely to 250 m (No.60) and prepared from the same bulk sample coal in the samelaboratory, by the same operator, using the same apparatus onsamples taken at random from a single quantity of homoge-neous material, may be expected to oc
36、cur with a probability ofapproximately 95 %.10.1.2.2 Reproducibility Limit (R)The value below whichthe absolute difference between two test results calculated to adry basis (Practice D 3180), carried out in different laborato-ries, using samples of 2.36 mm (No. 8) coal reduced entirely to250 m (No.
37、60), taken at random from a single quantity ofmaterial that is as homogeneous as possible, may be expectedto occur with a probability of approximately 95 %.10.2 BiasSince this is an empirical test method, thedegree of absolute bias cannot be determined.11. Keywords11.1 ash; coal; cokeANNEX(Mandatory
38、 Information)A1. PRECISION STATISTICS 250 m (No. 60) SAMPLESA1.1 The precision of this test method, characterized byrepeatability (Sr,r) and reproducibility (SR,R) has been deter-mined for the following materials as listed in Table A1.1.A1.2 Repeatability Standard Deviation (Sr)The standarddeviation
39、 of test results obtained under repeatability condi-tions.A1.3 Reproducibility Standard Deviation (SR)The stan-dard deviation of test results obtained under reproducibilityconditions.3An interlaboratory study, designed consistent with Practice E 691, was con-ducted in 1989. Eight laboratories partic
40、ipated in this study. Supporting data areavailable from ASTM Headquarters. Request Report RR: D051015.TABLE 1 Determination of Ash in the Analysis Sample of Coaland CokeRange RepeatabilityLimit,rReproducibilityLimit,R2.68 to 17.86 % 0.22 0.32TABLE 2 Range and Limits for Repeatability and Reproducabi
41、lityfor the Detrmination of Ash in Coal and CokeCoal Range RepeatabilityLimit,rReproducibilityLimit,RBituminous 5.0 to 15.0 % 0.30 % 0.49 %Subbituminous-Lignite 4.5 to 30.0 % 0.33 % 0.47 %TABLE A1.1 Repeatability (Sr,r) and Reproducibility (SR,R)Parameters Used for Calculation of Precision Statement
42、Material Average SrSRrR912 lvb 6.86364 0.049024 0.072788 0.13717 0.20366911 hvAb 2.68068 0.047123 0.055633 0.13185 0.15566915 hvAb 10.0873 0.065132 0.080675 0.18224 0.22573894 hvCb 10.475 0.075743 0.121383 0.21193 0.33963914 hvCb 12.515 0.071347 0.082831 0.19963 0.23176901 subB 16.7593 0.07752 0.130
43、6 0.2169 0.36542897 subA 8.81705 0.06302 0.10659 0.17633 0.29824916 subA 11.0723 0.061279 0.083981 0.17146 0.23498896 subC 13.5182 0.127066 0.194514 0.35553 0.54425Lignite 17.865 0.103367 0.163095 0.28922 0.45634D3174044ASTM International takes no position respecting the validity of any patent right
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