ASTM_D_4421_-_94_1999.pdf

Designation:D 4421 94(Reapproved 1999)An American National StandardStandard Test Method forVolatile Matter in Petroleum Coke1This standard is issued under the fixed designation D 4421;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(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method determines the volatile matter pro-duced by pyrolysis or evolved when petroleum coke,or both,is subjected to the specific conditions of the test.Sampleshaving a thermal history above 600C are excluded.1.2 This test method is empirical and requires the entire testprocedure to be closely followed to ensure results fromdifferent laboratories to be comparable.1.3 This test method is not satisfactory for dedusting mate-rial content.1.4 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.5 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.Specific precau-tionary statements are given in Section 8.2.Referenced Documents2.1 ASTM Standards:E 11 Specification for Wire-Cloth Sieves for Testing Pur-poses2E 220 Test Method for Calibration of Thermocouples byComparison Techniques33.Terminology3.1 Descriptions of Terms Specific to This Standard:3.1.1 analysis samplethe reduced and divided representa-tive portion of a bulk sample,prepared for use in the labora-tory.3.1.2 bulk samplethe reduced and divided representativeportion of a gross sample as prepared for shipment to andreceived by a laboratory,to be prepared for analysis.3.1.3 gross samplethe original,uncrushed,representativeportion taken from a shipment or lot of coke.3.1.4 petroleum cokea solid,carbonaceous residue pro-duced by thermal decomposition of heavy petroleum fractionsand cracked stocks.3.1.5 test samplethe weighed portion of the analysissample actually used in a test.3.1.6 volatile matteran empirical value equal to the massloss on heating expressed as a percent of the moisture freesample used.It is determined only by this ASTM standard forpetroleum coke.4.Summary of Test Method4.1 Volatile matter of a moisture free petroleum coke isdetermined by measuring the mass loss of the coke whenheated under the exact conditions of this procedure.5.Significance and Use5.1 The volatile matter of petroleum coke affects the densityof coke particles and can affect artifacts produced from furtherprocessing of the coke.5.2 The volatile matter can be used in estimating thecalorific value of coke.6.Interferences6.1 Moisture has a double effect.The mass loss is increasedand the moisture free sample weight is decreased by theamount of moisture actually present in the test sample.6.2 Particle Size Effect:6.2.1 The particle size range of the analysis sample affectsthe volatile matter.The coarser the analysis sample,the lowerthe volatile matter will be.The analysis sample(seeAnnexA1)is crushed to pass a No.60 sieve(0.250-mm opening)but is notovercrushed.A No.120 sieve(0.125-mm opening)shouldretain 40 to 55%of the sample.The analysis sample is not tobe obtained by scalping and discarding a portion of the sample.6.2.2 Any segregation of particle sizes within the analysissample shall be corrected by reblending the sample just prior toweighing the test sample.6.3 Downward drift of furnace temperature caused by anincrease in the millivolts per degrees Celsius generated by anaging type K thermocouple produces a lower volatile mattervalue(Test Method E 220).1This test method is under the jurisdiction of ASTM Committee D-2 onPetroleum Products and Lubricantsand is the direct responsibility of SubcommitteeD02.05 on Properties of Fuels,Petroleum Coke,and Oil Shale.Current edition approved Sept.15,1994.Published November 1994.Originallypublished as D 4421 84.Last previous edition D 4421 89.2Annual Book of ASTM Standards,Vol 14.02.3Annual Book of ASTM Standards,Vol 14.03.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.6.4 Diffusion of air into the crucible caused by a poor fitbetween the crucible and its cover or by any other source ofavailable oxygen causes high and erratic volatile matter values.6.5 Free or tramp iron or mill scale in the coke coats thesurface of the platinum crucible and decreases its life.Thecoating tends to form an oxide film during the preburning step(10.1).The oxide film provides a source of excess weight lossequal to almost twice the oxygen weight gained.Clean thecrucible and buff with sand.Buffing will restore luster to thesurface of the crucible.7.Apparatus7.1 Furnace,Fieldner,electric,ASTM,calibrated(TestMethod E 2