ASTM_D_197_-_87_2012.pdf

Designation:D19787(Reapproved 2012)Standard Test Method forSampling and Fineness Test of Pulverized Coal1This standard is issued under the fixed designation D197;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 the determination of the fine-ness by sieve analysis of coal sampled from a dry pulverizingoperation.It is not applicable to products of wet milling or tofines that have clustered into an agglomerated mass.1.2 The values stated in inch-pound units shall be regardedas the standard.Sample weights of 1000 g or less shall beexpressed in metric units.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:2E11 Specification for Woven Wire Test Sieve Cloth and TestSieves3.Significance and Use3.1 This test method provides a means for assisting in theevaluation of pulverizers and pulverizer systems in terms offineness specifications.It may also be used to confirm theinfluence of coal fineness on combustion performance and toevaluate carbon loss.By consent among interested parties,itmay be used for evaluation of coal fineness in preparation,pneumatic transfer systems,etc.4.Apparatus4.1 Sample ContainersHeavy vapor impervious bags,properly sealed,or noncorroding cans such as those with anairtight,friction top or screw top sealed with a rubber gasketand pressure sensitive tape for use in storage and transport ofthe laboratory sample.Glass containers sealed with rubbergaskets may be used,but care must be taken to avoid breakagein transport.4.2 Drying OvenA device for passing slightly heated airover the sample.The oven should be capable of maintaining atemperature of 18 to 27F(10 to 15C)above room tempera-ture with a maximum oven temperature of 104F(40C).Airchanges should be at the rate of 1 to 4/min.4.3 Sieves,square-hole,woven-wire cloth conforming toSpecification E11:No.8 USA Standard(2.36 mm)No.16 USA Standard(1.18 mm)No.30 USA Standard(600 m)No.50 USA Standard(300 m)No.100 USA Standard(150 m)No.200 USA Standard(75 m)No.325 USA Standard(45 m)The sieve frames shall be 8 in.(203 mm)in diameter,and theheight of the sieve from the top of the frame to the cloth shallbe either 2 in.(50.8 mm)or 1 in.(25.4 mm).Selection ofspecific sizes is optional,depending on the objective of the test.4.3.1 Since the finer mesh sieves in particular are suscep-tible to damage by distortion resulting from undue pressure,accidental scraping with hard brushes,etc.,each sieve shouldbe closely inspected and discarded if it shows evidence ofdamage.4.4 Mechanical Sieving MachineThe mechanical sievingmachine shall be designed to provide both a circular motionand a tapping action.It shall be designed to accept an assemblyof vertically nested circular sieves as described in 4.3.Themachine action shall be such that results as described inSection 7 are obtained within the allotted time frame.Actionshall not be sufficiently severe to generate new fines by particledegradation.To facilitate the sieving operation,a controlswitch device with timer is recommended.Other equipmentdesigns may be used provided the results are comparable.4.5 Balance,LaboratoryApproximately 1000-g capacity,sensitivity 0.1 g.4.6 Sampling Device(Storage System)An instrument(scoop,dipper,or other suitable device)for collecting incre-ments that will constitute the total sample.4.7 Sampling Device(Direct-Fired System)Apparatus asdescribed in 6.2.1 and 6.2.2.1This 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 in 1924.Last previous edition approved in 2007 as D197 87(2007).DOI:10.1520/D0197-87R12.2For 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 4.8 Sample Riffle with PansA manual sample divider thatsplits the coal stream into a number of alternate elements.Riffle divisions should be in the size range from14to12in.(6.4to 12.7 mm).5.Sampling,Storage System5.1 In the pulverized coal storage system,the coal afterpulverization is conveyed into bins.5.1.1 Collection of Gross SampleCollect not less than tenincrements of representative pulverized coal preferably as