ASTM_D_4371_-_06_2012.pdf

Designation:D437106(Reapproved 2012)Standard Test Method forDetermining the Washability Characteristics of Coal1This standard is issued under the fixed designation D4371;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 year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.INTRODUCTIONThe American Society for Testing and Materials has recognized the need for a standard procedureto conduct washability analyses that will serve as an aid to technical communication amongindividuals and organizations that supply,purchase,and utilize coal.This test method standardizesprocedures utilized for performing washability analyses,the data from which can be used forinterpreting preparation plant efficiency,for determining preparation plant design,and for determiningthe potential recovery and quality of coal reserves.1.Scope1.1 This test method describes procedures for determiningthe washability characteristics of coarse-coal fractions andfine-coal fractions.Each sample being tested can have morethan one coarse-coal size fraction and more than one fine-coalsize fraction(see Annex A1).Each such size fraction has anupper size limit and a lower size limit,neither of whichoverlaps with the next larger nor smaller size fraction.(SeeTest Method D4749.)1.2 While,in general,this test method has useful applicationin determining the washability characteristics of low-rankcoals,in the strictest sense,it is not necessarily the mosttechnically correct test method to determine washability char-acteristics of low-rank coals because of problems relative to theloss of moisture through drying during sample preparation andanalysis.Methods that are directly applicable to low-rank coalsare to be developed.1.3 The values stated in SI units are to be regarded as thestandard.The values shown in parentheses are for informationonly.1.4 This standard does not purport to address the safetyconcerns,if any,associated with its use.It is the responsibilityof the user of this standard to establish appropriate safety andhealth practices and determine the applicability of regulatorylimitations prior to use.For specific hazard statements,seeSection 8 and Appendix X1.2.Referenced Documents2.1 ASTM Standards:2D2013 Practice for Preparing Coal Samples for AnalysisD2234/D2234M Practice for Collection of a Gross Sampleof CoalD4749 Test Method for Performing the Sieve Analysis ofCoal and Designating Coal SizeD6883 Practice for Manual Sampling of Stationary Coalfrom Railroad Cars,Barges,Trucks,or StockpilesE11 Specification for Woven Wire Test Sieve Cloth and TestSievesE100 Specification for ASTM HydrometersE126 Test Method for Inspection,Calibration,and Verifica-tion of ASTM HydrometersE323 Specification for Perforated-Plate Sieves for TestingPurposes3.Terminology3.1 Definitions:3.1.1 coal washabilitythe determination of the theoreticallimits for the removal of mineral impurities from coal bybeneficiation processes that rely on specific gravity separa-tions.3.2 Definitions of Terms Specific to This Standard:3.2.1 washability analysis of coalthe analysis of thespecific gravity distribution of chemical and physical charac-teristics of coal.3.2.1.1 DiscussionIn this test method,the specific gravityfractions are obtained by subjecting the material being studied1This test method is under the jurisdiction of ASTM Committee D05 on Coaland Coke and is the direct responsibility of Subcommittee D05.07 on PhysicalCharacteristics of Coal.Current edition approved Sept.1,2012.Published November 2012.Originallypublished as approved in 1984.Last previous edition approved in 2006 asD4371 2006.DOI:10.1520/D4371-06R12.2For referenced ASTM standards,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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 to a series of solutions,each with a discrete specific gravity,that cover the range of specific gravities in question.In the caseof the washability analysis of coal,these solutions are obtainedby the mixing of various organic liquids that are relatively inerttoward the majority of coal types.The distribution,as deter-mined by the analysis,is affected by the physical condition ofthe sample subjected to the washability analysis,for example,the moisture content and the size content of the material.3.2.2 coarse coalthat portion of a coal sample beingsubjected to a washability study that is larger than a specificpredetermined particle size,generally between 2.36 mm(No.8USA Standard Sieve Series)and 9.5 mm(38in.)round indiameter.3.2.2.1 DiscussionThis same particle size breakpointshould then be used in subsequent washability studies of thesame material