ASTM_D_3802_-_16.pdf

Designation:D380216Standard Test Method forBall-Pan Hardness of Activated Carbon1This standard is issued under the fixed designation D3802;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.1.Scope1.1 This test method covers a procedure for determining theball-pan hardness number of granular activated carbons.Forthe purpose of this test,granular activated carbons are thosehaving particles 90%of which are larger than 80 mesh(180m)as determined by Test Method D2862.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 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:2B19 Specification for Cartridge Brass Sheet,Strip,Plate,Bar,and DisksB150/B150M Specification for Aluminum Bronze Rod,Bar,and ShapesD2652 Terminology Relating to Activated CarbonD2854 Test Method for Apparent Density of ActivatedCarbonD2862 Test Method for Particle Size Distribution of Granu-lar Activated CarbonD2867 Test Methods for Moisture in Activated CarbonE11 Specification for Woven Wire Test Sieve Cloth and TestSievesE300 Practice for Sampling Industrial Chemicals3.Terminology3.1 GeneralTerms applicable to this standard are definedin Terminology D2652.3.2 Definitions of Terms Specific to This Standard:3.2.1 nominal particle size:natural,granular,and irregu-larly shaped particle carbonsthat particle size range,ex-pressed in terms of Specification E11 sieve sizes,whose smallend excludes not more than 5%of the particle sizedistribution,and whose large end excludes not more than 5%of the distribution,on a weight basis.3.2.2 nominal particle size:pelleted carbonsthat particlesize range,expressed in terms of Specification E11 sieve sizes,whose small end excludes not more than 10%of the particlesize distribution,and whose large end excludes not more than5%of the distribution,on a weight basis.3.2.3 small end nominal particle sizethat particle size,expressed by its equivalent Specification E11 sieve,whichdefines the excluded portion of the particle size distribution atits small particle size end in accordance with 3.2.1 or 3.2.2.4.Summary of Test Method4.1 A screened and weighed sample of the carbon is placedin a special hardness pan with a number of stainless steel balls,then subjected to a combined rotating and tapping action for 30min.At the end of this period,the amount of particle sizedegradation is determined by measuring the quantity of carbon,by weight,which is retained on a sieve whose openings areclosest to one half the openings of the sieve that defines theminimum nominal particle size of the original sample.5.Significance and Use5.1 Several methods have been employed in the past fordetermining the resistance of activated carbons to particle sizedegradation under service conditions,including the ball-panmethod,the stirring bar method,and the dust elutriationmethod.None of these has proved completely satisfactory forall applications,and all have been questioned by ASTMCommittee D28 on Activated Carbon as tests for establishingdegradation resistance.However,the ball-pan method has beenused widely in the past and has a broad history in the activatedcarbon industry for measuring the property loosely describedas“hardness.”In this context the test is useful in establishinga measurable characteristic of a carbon.Conceding the fact thatthe test does not actually measure in-service resistance todegradation,it can be used to establish the comparability oflots ostensibly of the same grade of carbon.1This test method is under the jurisdiction of ASTM Committee D28 onActivated Carbon and is the direct responsibility of Subcommittee D28.04 on GasPhase Evaluation Tests.Current edition approved June 1,2016.Published July 2016.Originally approvedin 1979.Last previous edition approved in 2010 as D3802 10.DOI:10.1520/D3802-16.2For 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 6.Apparatus and Materials6.1 Mechanical Sieve Shaker,designed to produce from 140to 160 taps and from 280 to 320 rotating motions per minute ina stack of standard Specification E11 sieves.3Adjust the sieveshaker to accommodate the desired number of sieves,receiverpan,and sieve cover.Adjust the bottom stops to give aclearan