ASTM_D_1857_-_D_1857M_-_04_2010.pdf

Designation:D1857/D1857M04(Reapproved 2010)Standard Test Method forFusibility of Coal and Coke Ash1This standard is issued under the fixed designation D1857/D1857M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This test method covers the observation of the tempera-tures at which triangular pyramids(cones)prepared from coaland coke ash attain and pass through certain defined stages offusing and flow when heated at a specified rate in controlled,mildly reducing,and where desired,oxidizing atmospheres.1.2 The test method is empirical,and strict observance ofthe requirements and conditions is necessary to obtain repro-ducible temperatures and enable different laboratories to obtainconcordant results.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues from the two systems may result in non-conformancewith the standard.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 use.2.Referenced Documents2.1 ASTM Standards:2D2013 Practice for Preparing Coal Samples for AnalysisD3174 Test Method for Ash in the Analysis Sample of Coaland Coke from Coal3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 The critical temperature points to be observed are asfollows,denoting the atmosphere used:3.1.2 fluid temperature,FTthe temperature at which thefused mass has spread out in a nearly flat layer with amaximum height of 1.6 mm 116in.as shown by the fifthcone,FT,in Fig.1.3.1.3 hemispherical temperature,HTthe temperature atwhich the cone has fused down to a hemispherical lump atwhich point the height is one half the width of the base asshown by the fourth cone,HT,in Fig.1.3.1.4 initial deformation temperature,ITthe temperatureat which the first rounding of the apex of the cone occurs.Shrinkage or warping of the cone ignored if the tip remainssharp.In Fig.1,the first cone shown is an unheated one;thesecond cone IT is a typical cone at the initial deformation stage.3.1.5 softening temperature,STthe temperature at whichthe cone has fused down to a spherical lump in which theheight is equal to the width at the base as shown by the thirdcone,ST,in Fig.1.4.Significance and Use4.1 Design of most coal combustion and coal conversionequipment anticipates that the ash either remain solid orassume some degree of fluidity,depending on the particulardesign.Ash fusibility temperatures predict whether the ash willperform properly in the process for which the coal was chosen.5.Apparatus and Materials5.1 FurnaceAny gas-fired or electric furnace conformingto the following requirements may be used:5.1.1 Capable of maintaining a uniform temperature zone inwhich to heat the ash cones.This zone shall be such that thedifference in the melting point of 12.7-mm 12-in.pieces ofpure gold wire when mounted in place of the ash cones on thecone support shall be not greater than 11C 20F in areducing atmosphere test run.5.1.2 Capable of maintaining the desired atmosphere sur-rounding the cones during heating.The composition of theatmosphere,reducing or oxidizing,shall be maintained withinthe limits specified in Section 6.The desired atmosphere in thegas-fired furnace surrounding the cones shall be obtained byregulation of the ratio of gas to air in the combustion mixture.The desired atmosphere in the electric furnace shall be ob-tained by means of gases introduced into the heating chamber.1This test method is under the jurisdiction of ASTM Committee D05 on Coaland Coke and is the direct responsibility of D05.21 on Methods of Analysis.Current edition approved Sept.1,2010.Published November 2010.Originallyapproved 1961.Last previous edition approved 2004 as D1857 04.DOI:10.1520/D1857-04R10.2For 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 The muffle shall be gas impervious,free from cracks,and theclosure plug tight-fitting.The gas supply tube shall be sealed tothe back wall of the preheating chamber and shall not extend tothe front of the preheating chamber against the perforatedbaffle.5.1.3 Capable of regulation so