1、Designation: D 6316 04Standard Test Method forDetermination of Total, Combustible and Carbonate Carbonin Solid Residues from Coal and Coke1This standard is issued under the fixed designation D 6316; the number immediately following the designation indicates the year oforiginal adoption or, in the ca
2、se 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 covers the determination of total,combustible, and carbonate carbon rema
3、ining in the solidbyproducts of combustion from boiler furnaces and similarreactors, including ash, flyash, char, slag, and similar materials.1.2 This test method is intended for the use of industry todetermine the performance of boiler furnaces and similarcombustion reactors and aid in determining
4、the quality of thesolid residue from combustion.1.3 This test method comprises the use of any of severalmethods to determine total carbon content combined with anyof several methods to determine carbonate carbon, and thecalculation, by difference, of the combustible carbon remainingin a sample.1.4 A
5、lternatively, this test method applies to the determina-tion of total carbon remaining in a material after acidificationwith strong acid to evolve carbonate carbon. In this case, thecombustible carbon is the total carbon measured in the sampleafter acidification.1.5 The values stated in SI units are
6、 to be regarded as thestandard.1.6 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 to determine theapplicability of regulatory limitati
7、ons prior to use.2. Referenced Documents2.1 ASTM Standards:2D 121 Terminology of Coal and CokeD 513 Test Methods for Total and Dissolved Carbon Diox-ide in WaterD 1756 Test Method for Determination as Carbon Dioxideof Carbonate Carbon in CoalD 3178 Test Method for Carbon and Hydrogen in theAnalysis
8、Sample of Coal and CokeD 5373 Test Methods for Instrumental Determination ofCarbon, Hydrogen, and Nitrogen in Laboratory Samples ofCoal and CokeE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 Other Standards:ANSI/ASME Standard, PTC 38-1980 Determi
9、ning the Con-centration of Particulate Matter in A Gas Stream and USEPA Standard CFR 60 Appendix A, Method 1733. Terminology3.1 Definitions: For additional definitions of terms used inthis test method, refer to Terminology D 121.3.1.1 carbonate carbon, nthe carbon content present inthe solid product
10、s derived from the combustion or reaction ofcoal, coal byproducts, or coke as carbonates and which isnon-combustible in standard industry practice.3.1.2 combustible carbon, ncarbon content remaining inthe solid products derived from the combustion or reaction ofcoal, coal byproducts, or coke, exclus
11、ive of carbonate in anyform.3.1.3 total carbon, ncarbon content remaining in the solidproducts derived from the combustion or reaction of coal, coalbyproducts, or coke, inclusive of carbonate in any form.4. Summary of Test Method4.1 Total CarbonThe determination of total carbon ismade by the oxidati
12、ve thermal decomposition of a weighedquantity of sample in a closed system and, after completeoxidation and purification of the resulting gaseous products,measurement of the carbon dioxide produced by one of severalmethods.4.1.1 Absorptive Determination of Total CarbonTheevolved carbon dioxide is fi
13、xed on an absorption train and ismeasured quantitatively by weighing the absorbent (see TestMethods D 3178).4.1.2 Instrumental Determination of Total CarbonThecarbon dioxide is measured quantitatively by an electronic1This test method is under the jurisdiction of ASTM Committee D05 on Coaland Coke a
14、nd is the direct responsibility of Subcommittee D05.29 on MajorElements in Ash and Trace Elements of Coal.Current edition approved Nov. 1, 2004. Published December 2004. Originallyapproved in1998. Last previous edition approved in 2000 as D 6316 - 00.2For referenced ASTM standards, visit the ASTM we
15、bsite, 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.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.1Co
16、pyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.detection system calibrated against an appropriate referencestandard (see Test Methods D 5373).4.2 Carbonate CarbonThe determination of carbonatecarbon is made by decomposing a weighed qua
17、ntity of thesample with a dilute mineral acid, and after the purification ofthe evolved gases, measuring quantitatively the evolved carbondioxide.4.2.1 Absorptive Determination of Carbonate CarbonThecarbon dioxide is liberated by acidification and heating. Theevolved gases are passed through a purif
18、ication train and theCO2is fixed as Na2CO3on a preweighed absorption unit andis measured gravimetrically (see Test Method D 1756).4.2.2 Coulometric Determination of Carbonate CarbonThe carbon dioxide is liberated by acidification and heating.The evolved gas is swept through a scrubber and into anabs
19、orption cell where it is coulometrically titrated (see Part Bof Test Methods D 513).4.2.3 Instrumental Determination of Carbonate CarbonThe carbon dioxide is liberated by acidification and heating.The evolved gases are purified and measured quantitatively byan electronic detection system against an
20、appropriate referencestream. This test method resembles that for the instrumentaldetermination of total carbon, with the provision for samplecombustion replaced by a provision for acidification. In prac-tice, this test method uses an adaptation to instruments de-signed to measure total carbon conten
21、t.4.3 Combustible Carbon by Prior AcidificationThe deter-mination of combustible carbon is made directly by firstacidifying and heating to dryness a weighed sample. Allcarbonate carbon present is evolved as carbon dioxide. Thedried sample is then analyzed for total carbon content as above.No determi
22、nation of carbonate carbon is made and the carboncontent measured as total carbon is the combustible carbon.5. Significance and Use5.1 The combustible carbon content of solid residues is usedto calculate efficiency of fuel combustion in boiler furnaces andsimilar combustors.5.2 Combustible carbon va
23、lues are also used to determinethe residual fuel value of incompletely combusted coal andcoke in fluidized bed furnaces and other reactors whichconsume carbonaceous fuels.5.3 The combustible carbon content of flyash is an impor-tant parameter in the use of flyash as a cement additive.6. Interference
24、s6.1 The interferences for the determination of total carboncontent are those specified in the referenced standard methods,Test Methods D 3178 and Test Methods D 5373, with thefollowing added stipulation.6.1.1 The temperature and conditions of combustion thatensure complete conversion of a residue s
25、amples total carboncontent to carbon dioxide may be different than those requiredfor conversion in coal samples. It is absolutely imperative thatthe instrumental conditions used will ensure complete conver-sion of mineral carbonate in any amount or form.6.2 The interferences for the determination of
26、 carbonatecarbon are those specified in the referenced methods, TestMethod D 1756 and Part B of Test Methods D 513 with thefollowing stipulation6.2.1 Some coal combustion residues contain significantamounts of reactive elements such as CaO which will absorbcarbon dioxide on exposure to open air and
27、form mineralcarbonates. This will influence the calculated amount ofcombustible carbon in the sample only if there was carbondioxide chemisorption from the air between the time of thecarbonate determination and the total carbon determination.Therefore, it is necessary that the sample be protected fr
28、om airexposure.6.3 The mineral acid and temperature required for prioracidification of the analytical sample shall not interfere withthe amount of combustible carbon present in the sample or theanalytical determination of carbon. The use of oxidizing acidssuch as concentrated nitric acid may oxidize
29、 a portion of thecombustible carbon. Other acids such as hydrochloric acid maybe incompatible with the reagents used to purify the gas streamin the instrumental determination of carbon. Sulfuric acid hasa relatively high boiling point and is difficult to remove fromthe sample by drying. A solution o
30、f 10 % nitric acid issuggested for use in this procedure.7. Apparatus7.1 The apparatus used is specified in the respective refer-enced method.7.2 Total Carbon Content:7.2.1 Absorptive Determination of Total CarbonThe ap-paratus consists of an oxygen-purifying train, combustion unit,and absorption tr
31、ain of the type and configuration specified inTest Methods D 3178.7.2.2 Instrumental Determination of Total CarbonBecause a variety of instrumental components and configura-tions can be used satisfactorily for these test methods, nospecifications are presented here with respect to overall systemdesi
32、gn. However, the apparatus shall be capable of completelyconverting the carbon content to carbon dioxide, and thedetection system shall determine the carbon dioxide individu-ally and without interference.7.3 Carbonate Carbon Content:7.3.1 Absorptive Determination of Carbonate CarbonTheapparatus shal
33、l consist of an air purifying train, reaction unit,and absorption unit of the type and configuration specified inTest Method D 1756.7.3.2 Coulometric Determination of Carbonate CarbonThe apparatus shall consist of an evolution unit, a carbondioxide coulometer, scrubber, and pH meter of the type andc
34、onfiguration specified in Part B of Test Methods D 513.7.3.3 Instrumental Determination of Carbonate CarbonThe apparatus shall consist of a heated acidification unit that isinstalled by bypassing the combustion system in a devicedesigned for the determination of total carbon content. Thegas-purifyin
35、g system of such instrument shall be capable ofcompletely removing the water content and acid gases pro-duced as byproducts of the carbon dioxide evolution. Thedetection system shall measure the evolved carbon dioxide asan individual species and without interference.D63160427.4 Combustible Carbon by
36、 Prior AcidificationThe cru-cibles used for this method must be free of carbonate, inert tothe mineral acid used, and compatible with the instrument usedfor measuring total carbon. The acidified sample is heated todryness using a laboratory hotplate capable of maintaining thefine temperature control
37、 required to dry the sample withoutmaterial loss of sample as a result of spattering or boilover. Theinstrument used shall meet the requirements of Test MethodsD 5373 and be capable of removing the additional acid gasesthat result from the mineral acid used for evolving the carbondioxide before dete
38、rmining carbon content.8. Reagents8.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specificatio
39、ns are available.4Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.9. Standards9.1 There are currently no standard reference materials ofcoal or coke residues that are certifi
40、ed for combustible carbonor carbonate carbon content. However, other types of standardmaterials can be used for both method validation and instru-ment calibration. These include:9.1.1 Buffalo River Sediment (NIST 2704)Total carbon =3.348 6 0.016 %.9.1.2 Carbonate Primary Standard GradeFor example,Ca
41、CO3total carbonate carbon = 12.00 %.9.1.3 CoalBituminous (NIST 1632b) total carbon = 76.866 0.26 %.9.1.4 EDTA Primary Standard GradeTotal carbon =41.07 %.10. Sample Preparation10.1 If moist or wet, the combustion residue sample5will bepredried at 107 6 3C. Drying time should be the minimumrequired t
42、o ensure complete dryness of the sample to minimizeabsorption of carbon dioxide from the air (see 6.2.1).10.2 The method of sample preparation used is specified inthe respective referenced method.10.3 Samples in excess of 50 g should be divided by rifflingto ensure a representative analysis sample.
43、Samples of 50 g orless should be prepared in their entirety.10.4 The analysis sample shall initially be prepared to passthrough a 250-m (# 60 U.S. standard) sieve. If required by thecharacteristics of the instrument system or analytical precisionof the resulting data or both, the analysis sample sho
44、uld beground to pass through a 75-m (# 200 U.S. standard) sieve.611. Instrument Preparation and Verification11.1 The preparation of equipment and instruments is speci-fied in the respective referenced methods and the manufactur-ers instructions.11.2 The proper functioning of the equipment and theope
45、rational parameters should be verified by analyzing blanksand standard materials that contain carbonate carbon andcombustible carbon.11.2.1 The proper combustion temperature and conditionsnecessary to convert the carbonate carbon to carbon dioxidemay be determined by measuring the carbon content of
46、acarbonate standard. Measured carbon values of less than thecertified value indicate incomplete conversion of carbonates.11.2.2 Combustion accelerants such as magnesium powder,thermite (aluminum powder and iron oxide), and tin powdercan be used to ensure the total conversion of carbonates tocarbon d
47、ioxide by significantly raising the reaction temperatureduring combustion.12. Procedure12.1 Calibrate the instruments using the methods describedin the referenced methods.12.1.1 The calibration range for these measurements shouldbe in the range of expected carbon values for the analyticalsamples.12.
48、2 Determine the total carbon content of the samplematerial by any of the referenced methods.12.3 Determine the carbonate carbon content of the samplematerial by any of the referenced methods, or12.4 Combustible Carbon by Prior AcidificationTare acrucible appropriate to the carbon analyzer used7to th
49、e nearest0.1 mg. Weigh a 100- to 500-mg portion of the analysis sampleto the nearest 0.1 mg. Add a sufficient amount of 10 % HNO3dropwise to wet the sample. Allow the sample to stand forseveral minutes. Dry the sample completely on a hotplate withlow heat (150C), taking care that the sample does not spatter.Allow the sample and crucible to cool. Proceed to analyze thesample for total carbon with the method prescribed in theappropriate standard method.13. Calculation13.1 For samples in which the total carbon and carbonatecarbon have been determined, calculate
