ASTM_D_6722_-_11.pdf

Designation:D672211Standard Test Method forTotal Mercury in Coal and Coal Combustion Residues byDirect Combustion Analysis1This standard is issued under the fixed designation D6722;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 These test methods cover procedures to determine thetotal mercury content in a sample of coal or coal combustionresidue.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 WarningMercury has been designated by EPA andmany state agencies as a hazardous material that can causecentral nervous system,kidney,and liver damage.Mercury,orits vapor,may be hazardous to health and corrosive tomaterials.Caution should be taken when handling mercury andmercury-containing products.See the applicable product Ma-terial Safety Data Sheet(MSDS)for details and EPAs website(http:/www.epa.gov/mercury/faq.htm)for additional informa-tion.Users should be aware that selling mercury or mercury-containing products,or both,in your state may be prohibited bystate law.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:2D121 Terminology of Coal and CokeD2013/D2013M Practice for Preparing Coal Samples forAnalysisD3173 Test Method for Moisture in the Analysis Sample ofCoal and CokeD3180 Practice for Calculating Coal and Coke Analysesfrom As-Determined to Different BasesD4621 Guide for Quality Management in an OrganizationThat Samples or Tests Coal and Coke(Withdrawn 2010)3D7582 Test Methods for Proximate Analysis of Coal andCoke by Macro Thermogravimetric AnalysisIEEE/ASTM SI 10 Standard for Use of the InternationalSystem of Units(SI):The Modern Metric System3.Terminology3.1 For definitions of terms used in this standard,refer toTerminology D121.4.Summary of Test Method4.1 Controlled heating of the analysis sample in oxygen isused to liberate mercury.The sample is heated to dryness in theinstrument and then thermally and chemically decomposed.The decomposition products are carried by flowing oxygen tothe catalytic section of the furnace,where oxidation is com-pleted and halogens as well as nitrogen and sulfur oxides aretrapped.The remaining decomposition products are carried toa gold amalgamator that selectively traps mercury.After thesystem is flushed with oxygen to remove any remainingdecomposition products,the amalgamator is rapidly heated,releasing mercury vapor.Flowing oxygen carries the mercuryvapor through absorbance cells positioned in the light path ofa single wavelength atomic absorption spectrophotometer.Absorbance peak height or peak area,as a function of mercuryconcentration,is measured at 253.7 nm.NOTE1Mercury and mercury salts can be volatized at low tempera-tures.Precautions against inadvertent mercury loss should be taken whenusing this method.5.Significance and Use5.1 The emission of mercury during coal combustion can bean environmental concern.5.2 When representative test portions are analyzed accord-ing to this procedure,the total mercury is representative ofconcentrations in the sample.1This test method is under the jurisdiction of ASTM Committee D05 on Coaland Coke and is the direct responsibility of Subcommittee D05.29 on MajorElements in Ash and Trace Elements of Coal.Current edition approved June 1,2011.Published June 2011.Originallyapproved in 2001.Last previous edition approved in 2006 as D672201(2006).DOI:10.1520/D6722-11.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.Apparatus6.1 There are several configurations of the instrumentalcomponents that can be used satisfactorily for this test method.Functionally,the instrument shall have the following compo-nents:drying compartment,decomposition tube,catalyst tube,gold amalgamator,amalgamator furnace,measuring cuvettes,mercury lamp,and detector.The following requirements arespecified for all approved instruments.(Note 2).NOTE2The approval of an instrument with respect to these functionsis paramount to this test method,since such approval tacitly providesapproval of both the materials and the procedures used with the system toprovide these functions.6.1.1 The instrument shall