1、Designation: D388 12Standard Classification ofCoals by Rank1This standard is issued under the fixed designation D388; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the
2、year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This standard covers the classification of coals by rank,that is, according to their degree of metamorphism, or progres-sive alteration, in the natural series from lignite
3、 to anthracite.1.2 This classification is applicable to coals that are com-posed mainly of vitrinite.NOTE 1Coals rich in inertinite or liptinite (exinite), or both, cannot beproperly classified because, in those macerals, the properties that deter-mine rank (calorific value, volatile matter, and agg
4、lomerating character)differ greatly from those of vitrinite in the same coal. Often such coals canbe recognized by megascopic examination. In North America, these coalsare mostly nonbanded varieties that contain only a small proportion ofvitrain and consist mainly of attrital materials. The degree o
5、f metamor-phism of nonbanded and other vitrinite-poor coals can be estimated bydetermining the classification properties of isolated or concentratedvitrinite fractions, or by determining the reflectance of the vitrinite (seeTest Method D2798 and Appendix X1 of this classification). However, inthe us
6、e of these vitrinite-poor coals, some properties normally associatedwith rank, such as rheology, combustibility, hardness, and grindability (aswell as the rank determining properties) may differ substantially fromthose of vitrinite-rich coals of the same degree of metamorphism.The precision of the c
7、lassification of impure coal may beimpaired by the effect of large amounts of mineral matter onthe determination of volatile matter and calorific value, and ontheir calculation to the mineral-matter-free basis.1.3 The values stated in SI units are to be regarded asstandard. No other units of measure
8、ment are included in thisstandard.1.3.1 ExceptionThe values stated in British thermal unitsper pound are to be regarded as the standard. The SI equiva-lents of British thermal units per pound are approximate.2. Referenced Documents2.1 ASTM Standards:2D121 Terminology of Coal and CokeD720 Test Method
9、 for Free-Swelling Index of CoalD1412 Test Method for Equilibrium Moisture of Coal at 96to 97 Percent Relative Humidity and 30CD1757 Test Method for Sulfate Sulfur inAsh from Coal andCoke3D2013 Practice for Preparing Coal Samples for AnalysisD2234/D2234M Practice for Collection of a Gross Sampleof C
10、oalD2798 Test Method for Microscopical Determination of theVitrinite Reflectance of CoalD3172 Practice for Proximate Analysis of Coal and CokeD3173 Test Method for Moisture in the Analysis Sample ofCoal and CokeD3174 Test Method forAsh in theAnalysis Sample of Coaland Coke from CoalD3175 Test Method
11、 for Volatile Matter in the AnalysisSample of Coal and CokeD3177 Test Methods for Total Sulfur in the AnalysisSample of Coal and CokeD3302 Test Method for Total Moisture in CoalD4239 Test Method for Sulfur in the Analysis Sample ofCoal and Coke Using High-Temperature Tube FurnaceCombustionD4596 Prac
12、tice for Collection of Channel Samples of Coalin a MineD5016 Test Method for Total Sulfur in Coal and CokeCombustion Residues Using a High-Temperature TubeFurnace Combustion Method with Infrared AbsorptionD5192 Practice for Collection of Coal Samples from CoreD5865 Test Method for Gross Calorific Va
13、lue of Coal andCoke3. Terminology3.1 DefinitionsFor additional definitions of terms used inthis classification, refer to Terminology D121.3.1.1 agglomerating, adjas applied to coal, the propertyof softening when it is heated to above about 400C in anonoxidizing atmosphere, and then appearing as a co
14、herentmass after cooling to room temperature.3.1.2 apparent rank, nof coal, the rank designation ob-tained on samples other than channel samples or core sampleswith 100 % recovery, but otherwise conforming to proceduresof Classification D388.1This classification is under the jurisdiction of ASTM Com
15、mittee D05 on Coaland Coke and is the direct responsibility of Subcommittee D05.18 on Classificationof Coals.Current edition approved March 15, 2012. Published March 2012. Originallyapproved in 1934. Last previous edition approved in 2005 as D388 05. DOI:10.1520/D0388-12.2For referenced ASTM standar
16、ds, 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 page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.ast
17、m.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.3 coal seam, nthe stratum, layer, or bed of coal thatlies between two other rock layers whose compositions differsignificantly from that of coal.3.2 Abbreviations:Where it is
18、desired to abbreviate thedesignation of the ranks of coal, the following abbreviationsshall be used:mameta-anthraciteananthracitesasemianthracitelvblow volatile bituminousmvbmedium volatile bituminoushvAbhigh volatile A bituminoushvBbhigh volatile B bituminoushvCbhigh volatile C bituminoussubAsubbit
19、uminous AsubBsubbituminous BsubCsubbituminous CligAlignite AligBlignite B4. Significance and Use4.1 This classification establishes categories of coal basedon gradational properties that depend principally on the degreeof metamorphism to which the coal was subjected whileburied. These categories ind
20、icate ranges of physical andchemical characteristics that are useful in making broadestimates of the behavior of coal in mining, preparation, anduse.5. Basis of Classification5.1 Classification is according to fixed carbon and grosscalorific value (expressed in British thermal units per pound)calcul
21、ated to the mineral-matter-free basis. The higher-rankcoals are classified according to fixed carbon on the dry basis;the lower-rank coals are classified according to gross calorificvalue on the moist basis. Agglomerating character is used todifferentiate between certain adjacent groups.6. Classific
22、ation by Rank6.1 Fixed Carbon and Gross Calorific ValueCoals shallbe classified by rank in accordance with Table 1. Classify coalshaving gross calorific values of 14 000 Btu/lb or more on themoist, mineral-matter-free basis, and coals having fixed carbonof 69 % or more on the dry, mineral-matter-fre
23、e basis, accord-ing to fixed carbon on the dry, mineral-matter-free basis.Classify coals having gross calorific values less than 14 000Btu/lb on the moist, mineral-matter-free basis according togross calorific value on the moist, mineral-matter-free basis,provided the fixed carbon on the dry, minera
24、l-matter-free basisis less than 69 %.6.2 Agglomerating CharacterClassify coals having 86 %or more fixed carbon on the dry, mineral-matter-free basis, ifagglomerating, in the low volatile group of the bituminousTABLE 1 Classification of Coals by RankAClass/GroupFixed Carbon Limits(Dry, Mineral-Matter
25、-FreeBasis), %Volatile Matter Limits(Dry, Mineral-Matter-FreeBasis), %Gross Calorific Value Limits(Moist,BMineral-Matter-Free Basis)AgglomeratingCharacterBtu/lb Mj/kgCEqual orGreaterThanLessThanGreaterThanEqual orLess ThanEqual orGreaterThanLess ThanEqual orGreaterThanLess ThanAnthracitic:Meta-anthr
26、acite 98 . . 2 . . . .JAnthracite 92 98 2 8 . . . . . . . . . . . . nonagglomeratingSemianthraciteD86 92 8 14 . . . .Bituminous:Low volatile bituminous coal 78 86 14 22 . . . . . . . . . . . .6commonlyagglomeratingEMedium volatile bituminous coal 69 78 22 31 . . . . . . . . . . . .High volatile A bi
27、tuminous coal . . . 69 31 . . . 14 000F. . . 32.557 . . .High volatile B bituminous coal . . . . . . . . . . . . 13 000F14 000 30.232 32.557High volatile C bituminous coal . . . . . . . . . . . .H11 500 13 000 26.743 30.23210 500 11 500 24.418 26.743 agglomeratingSubbituminous:Subbituminous A coal .
28、 . . . . . . . . . . . 10 500 11 500 24.418 26.7436Subbituminous B coal . . . . . . . . . . . . 9 500 10 500 22.09 24.418Subbituminous C coal . . . . . . . . . . . . 8 300 9 500 19.30 22.09nonagglomeratingLignitic:Lignite A . . . . 6300G8 300 14.65 19.30Lignite B . . . . . 6300 . 14.65AThis classifi
29、cation does not apply to certain coals, as discussed in Section 1.BMoist refers to coal containing its natural inherent moisture but not including visible water on the surface of the coal.CMegajoules per kilogram. To convert British thermal units per pound to megajoules per kilogram, multiply by 0.0
30、023255.DIf agglomerating, classify in low volatile group of the bituminous class.EIt is recognized that there may be nonagglomerating varieties in these groups of the bituminous class, and that there are notable exceptions in the high volatile Cbituminous group.FCoals having 69 % or more fixed carbo
31、n on the dry, mineral-matter-free basis shall be classified according to fixed carbon, regardless of gross calorific value.GEditorially corrected.D388 122class. Classify coals having gross calorific values in the rangefrom 10 500 to 11 500 Btu/lb on the moist, mineral-matter-freebasis according to t
32、heir agglomerating character (Table 1).6.3 Supplemental InformationAcorrelation of the rankingproperty, volatile matter (100fixed carbon), with the mean-maximum reflectance of the vitrinite group macerals in coalstested in one laboratory over a period of several years is shownin Appendix X1.7. Sampl
33、ing7.1 SamplesClassify a coal seam, or part of a coal seam,in any locality based on the average analysis and gross calorificvalue (and agglomerating character where required) of not lessthan three and preferably five or more whole seam samples,either face channels or cores, taken in different and un
34、iformlydistributed localities, either within the same mine or closelyadjacent mines representing a continuous and compact area notgreater than approximately four square miles in regions ofgeological uniformity. In regions in which conditions indicatethat the coal probably varies rapidly in short dis
35、tances, thespacing of sampling points and grouping of analyses to provideaverage values shall not be such that coals of obviouslydifferent rank will be used in calculating average values.7.1.1 Take channel samples by excluding mineral partingsmore than 1 cm (38 in.) and lenses or concretions (such a
36、ssulfur balls) more than 1.25 cm (12 in.) thick and 5 cm (2 in.)wide, as specified in Practice D4596.7.1.2 A drill core sample may be used provided it wascollected as specified in Practice D5192 and meets the follow-ing provisions: core recovery is 100 % of the seam, the majormineral partings and co
37、ncretions are excluded as specified in7.1.1, and drilling mud is removed from the core (see also7.1.6).7.1.3 Place all samples in metal or plastic cans with airtightlids, or heavy vapor impervious bags, properly sealed topreserve inherent moisture.7.1.4 Analyses of samples from outcrops or from weat
38、heredor oxidized coal shall not be used for classification by rank.7.1.5 In case the coal is likely to be classified on the moistbasis, that is, inclusive of its natural complement of inherentmoisture, take samples in a manner most likely to preserveinherent moisture for purposes of analysis. Becaus
39、e some ofthe moisture in a freshly collected sample condenses on theinside of the sample container, weigh both the container andthe coal before and after air drying, and report the total loss inweight as air-drying loss.7.1.6 If the sample is a core or if it is impossible to samplethe coal without i
40、ncluding visible surface moisture, or if theremay be other reasons to question the accuracy of inherentmoisture content determinable from the sample, and the coal islikely to be classified on the moist basis, the sampler shallinclude the following statement in the description: Moisturequestionable.
41、Samples so marked shall not be used for classi-fication on a moist basis unless brought to a standard conditionof moisture equilibrium at 30C in a vacuum desiccatorcontaining a saturated solution of potassium sulfate (97 %humidity) as specified in Test Method D1412.Analyses of suchsamples that have
42、been treated in this manner shall bedesignated as samples equilibrated at 30C and 97 % humidity.7.2 Other Types of SamplesAstandard rank determinationcannot be made unless samples have been obtained in accor-dance with 7.1. However, the relation to standard determina-tions may be usefully given for
43、other types of samples takenunder unspecified conditions, providing the same standards ofanalysis and computation are followed. Designate these com-parative indications as apparent rank, which indicates thecorrect relative position for the sample analyzed but does notimply any standards of sampling.
44、 Whenever apparent rank isstated, give additional information as to the nature of thesample.7.2.1 The apparent rank of the coal product from a mineshall be based on representative samples taken in accordancewith the Organization and Planning of Sampling Operationssection (Section 7) of Practice D223
45、4/D2234M.7.2.2 In case the coal is likely to be classed on the moistbasis, take samples at the tipple or preparation plant and sealthe sample to prevent loss of moisture.8. Methods of Analysis and Testing8.1 Laboratory Sampling and AnalysisPrepare coal inaccordance with Method D2013 and analyze it i
46、n accordancewith Test Methods D3173, D3174, D3175, D3177 or D4239,D3302, and Practice D3172. Determine its gross calorific valuein accordance with Test Method D5865. Determine the sulfurtrioxide (SO3) retained in the ash in accordance with TestMethod D1757 or D5016 and express the result on a dry ba
47、sis.Inherent moisture is reported as as-received moisture if thesample was collected according to 7.1.1 or as equilibriummoisture if 7.1.6 (Test Method D1412) applies.8.2 Adjust the ash value determined in accordance with TestMethod D3174 to be free of sulfate as follows:A 5 AdS12SO3100DS12M100D(1)w
48、here:A = adjusted ash value on the inherent moist basis,Ad= ash yield, dry basis, determined in accordance withTest Method D3174,SO3= in the ash determined in accordance with TestMethod D1757 or D5016, andM = inherent moisture.Add to the value of fixed carbon that is determined inaccordance with Pra
49、ctice D3172 the value of the SO3deter-mined in the ash to obtain the value FC to be used in Eq 2.8.3 Agglomerating CharacterThe test carried out by theexamination of the residue in the platinum crucible incident tothe volatile matter determination shall be used.4Coals which,in the volatile matter determination, produce either an agglom-erate button that will support a 500-g weight without pulver-izing, or a button showing swelling or cell structure, shall beconsidered agglomerating from the standpoint of classification.In addition, a result of 1.0 o
