1、Designation:D471598(Reapproved 2017)Standard Test Method forCoking Value of Tar and Pitch(Alcan)1This standard is issued under the fixed designation D4715;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A nu
2、mber in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of the cokingvalue of tar and pitch having an ash content not over 0.5%,asdetermined by Test Method
3、 D2415.1.2 Coking values by this test method are higher than thoseobtained by Test Method D2416.See the bias statement inSection 13.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.4 This standard does not purport to address
4、 all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in
5、accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 AST
6、M Standards:2D850 Test Method for Distillation of Industrial AromaticHydrocarbons and Related MaterialsD2415 Test Method for Ash in Coal Tar and PitchD2416 Test Method for Coking Value of Tar and Pitch(Modified Conradson)D4296 Practice for Sampling PitchE11 Specification for Woven Wire Test Sieve Cl
7、oth and TestSieves3.Summary of Test Method3.1 A test portion of the tar or pitch is heated for a specifiedtime at 550 C 6 10 C in an electric furnace.The percentageof residue is reported as the coking value.4.Significance and Use4.1 This test method is useful for indicating the relativecoke-forming
8、propensities and for evaluating and characteriz-ing tars and pitches.The test method can also be used as oneelement in establishing the uniformity of shipments or sourcesof supply.5.Apparatus5.1 Porcelain Crucible,tall form,30 mL capacity,height of37 mm and diameter 43 mm,with lids of the overlappin
9、g type.5.2 Nickel Crucible,100 mL to 130 mL capacity,height of64 mm and diameter of 60 mm,with lids.5.3 Wire SupportStainless steel wire support,fitting intothe nickel crucible,used to keep the porcelain crucible(5.1)inplace within the nickel crucible(5.2).This support shall allowa separation of 10
10、mm 6 1 mm between the bases of the twocrucibles(see Fig.1).5.4 Crucible TrayA suitable crucible tray to support thenickel crucibles should be made so that there is at least 7 mmof space between the bottom of the crucible and the base of thefurnace.5.5 Electric Furnace,capable of being controlled at
11、550 C6 10 C.5.6 Sieves1 mm(U.S.Standard No.18),300 m(U.S.Standard No.50)and 212 m(U.S.Standard No.70),conforming to Specification E11.6.Reagents and Materials6.1 Calcined Petroleum CokeUse the fraction whichpasses a 1 mm mesh sieve(U.S.Standard No.18)and isretained by a 212 m mesh sieve(U.S.Standard
12、 No.70).7.Bulk Sampling7.1 Samples from shipments shall be taken in accordancewith Practice D4296,and shall be free of foreign substances.Thoroughly mix the sample immediately before removing arepresentative portion for the determination or for dehydration.1This test method is under the jurisdiction
13、 of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.05 on Properties of Fuels,Petroleum Coke and Carbon Material.Current edition approved Oct.1,2017.Published November 2017.Originallyapproved in 1987.Last previous edition approv
14、ed in 2012 as D4715 98(2012).DOI:10.1520/D4715-98R17.2For 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 AST
15、M International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards
16、,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 8.Dehydration of Sample8.1 Hard PitchIf the solid bulk sample contains freewater,air-dry a representative portion.8.2 Soft PitchIf the presence of water is indicated bysurface foam on heating,maintain a representative portion ofthe bulk sample at a temperature between 125 C and 150 C inan open container until the surface is free from foam.Take carenot to overheat,and remove heat source
