1、Designation: D 5865 07Standard Test Method forGross Calorific Value of Coal and Coke1This standard is issued under the fixed designation D 5865; 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
2、 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 pertains to the determination of thegross calorific value of coal and coke by either an isoperibol oradiabatic bomb calorimete
3、r.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 ap
4、pro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Specific hazardstatements are given in Section 8.2. Referenced Documents2.1 ASTM Standards:2D 121 Terminology of Coal and CokeD 346 Practice for Collection and Preparation of CokeSamples f
5、or Laboratory AnalysisD 388 Classification of Coals by RankD 1193 Specification for Reagent WaterD 2013 Practice for Preparing Coal Samples for AnalysisD 3173 Test Method for Moisture in theAnalysis Sample ofCoal and CokeD 3177 Test Methods for Total Sulfur in the AnalysisSample of Coal and CokeD 31
6、80 Practice for Calculating Coal and Coke Analysesfrom As-Determined to Different BasesD 4239 Test Methods for Sulfur in the Analysis Sample ofCoal and Coke Using High-Temperature Tube FurnaceCombustion MethodsD 5142 Test Methods for Proximate Analysis of the Analy-sis Sample of Coal and Coke by Ins
7、trumental ProceduresE1 Specification for ASTM Liquid-in-Glass ThermometersE 144 Practice for Safe Use of Oxygen Combustion BombsE 178 Practice for Dealing With Outlying ObservationsE 882 Guide for Accountability and Quality Control in theChemical Analysis Laboratory3. Terminology3.1 Definitions:3.1.
8、1 adiabatic calorimetera calorimeter that operates inthe adiabatic mode and may or may not use a microprocessor.The initial temperature before initiating the combustion and thefinal temperatures are recorded by the operator or the micro-processor.3.1.2 automated calorimetera calorimeter which has am
9、icroprocessor that takes the thermometric readings and cal-culates the Calibration Value and the Heat of CombustionValues.3.1.3 British thermal unit Btuis the amount of heatrequired to raise the temperature of one pound - mass lbm ofliquid water at one atmosphere pressure one degree Fahrenheitat a s
10、tated temperature. The results of combustion calorimetrictests of fuels for steam power plants may be expressed in termsof the 1956 International Steam Table calorie (I.T. cal) whichis defined by the relation, 1 I.T. cal = 4.1868 J. The Btu usedin modern steam tables is defined by the means of the r
11、elation,1I.T.cal/g=1.8I.T.Btu/lb.Thus, 1 I.T. Btu / lb = 2.326 J/g.3.1.4 calorific valuethe heat produced by combustion of aunit quantity of a substance under specified conditions.3.1.5 calorimetera device for measuring calorific valueconsisting of a bomb, its contents, a vessel for holding thebomb,
12、 temperature measuring devices, ignition leads, water,stirrer, and a jacket maintained at specified temperature con-ditions.3.1.6 gross calorific value (gross heat of combustion atconstant volume), Qv(gross)the heat produced by completecombustion of a substance at constant volume with all waterforme
13、d condensed to a liquid.3.1.7 heat of formationthe change in heat content result-ing from the formation of 1 mole of a substance from itselements at constant pressure.3.1.8 isoperibol calorimetera calorimeter that operates inthe isoperibol mode and uses a microprocssor to record theinitial and final
14、 temperatures and make the appropiate heat leak1This test method is under the jurisdiction of ASTM Committee D05 on Coaland Coke and is the direct responsibility of Subcommittee D05.21 on Methods ofAnalysis.Current edition approved July 15, 2007. Published August 2007. Originallyapproved in 1995. La
15、st previous edition approved in 2003 as D 5865 03a.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.1Copyright
16、 ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.corrections during the temperature rise. It determines when thecalorimeter is in equilibrium and ignites the sample anddetermines when the calorimeter has reached equilibrium afterignition.3.1.9
17、net calorific value (net heat of combustion at constantpressure), Qp(net)the heat produced by combustion of asubstance at a constant pressure of 0.1 MPa (1 atm), with anywater formed remaining as vapor.3.2 Definitions of Terms Specific to This Standard:3.2.1 corrected temperature risethe calorimeter
18、 tempera-ture change caused by the process that occurs inside the bombcorrected for various effects.3.2.2 heat capacitythe energy required to raise the tem-perature of the calorimeter one arbitrary unit.3.2.2.1 DiscussionThe heat capacity can also be referredto as the energy equivalent or water equi
19、valent of the calorim-eter.4. Summary of Test Method4.1 The heat capacity of the calorimeter is determined byburning a specified mass of benzoic acid in oxygen. Acomparable amount of the analysis sample is burned under thesame conditions in the calorimeter. The calorific value of theanalysis sample
20、is computed by multiplying the correctedtemperature rise, adjusted for extraneous heat effects, by theheat capacity and dividing by the mass of the sample.NOTE 1Oxidation of coal after sampling can result in a reduction ofcalorific value. In particular, lignite and sub-bituminous rank coal samplesma
21、y experience greater oxidation effects than samples of higher rankcoals. Unnecessary exposure of the samples to the air for the time ofsampling or delay in analysis should be avoided.5. Significance and Use5.1 The gross calorific value can be used to compute thetotal calorific content of the quantit
22、y of coal or coke repre-sented by the sample for payment purposes.5.2 The gross calorific value can be used for computing thecalorific value versus sulfur content to determine whether thecoal meets regulatory requirements for industrial fuels.5.3 The gross calorific value can be used to evaluate the
23、effectiveness of beneficiation processes.5.4 The gross calorific value can be required to classifycoals according to Classification D 388.6. Apparatus and Facilities6.1 Test AreaAn area free from drafts, shielded fromdirect sunlight and other radiation sources. Thermostatic con-trol of room temperat
24、ure and controlled relative humidity aredesirable.6.2 Combustion BombConstructed of materials that arenot affected by the combustion process or the products formedto introduce measurable heat input or alteration of end prod-ucts. The bomb shall be designed so that all liquid combustionproducts can b
25、e completely recovered by washing the innersurfaces. There shall be no gas leakage. The bomb shall becapable of withstanding a hydrostatic pressure test to 20 MPa(3000 psig) at room temperature without stressing any partbeyond its specified elastic limit.6.3 BalanceAlaboratory balance capable of wei
26、ghing theanalysis sample to the nearest 0.0001 g. The balance shall bechecked weekly, at a minimum, for accuracy.6.4 Calorimeter VesselMade of metal with a tarnish-resistant coating, with all outer surfaces highly polished. Itssize shall be such that the bomb is completely immersed inwater during a
27、determination. A stirrer shall be provided foruniform mixing of the water. The immersed portion of thestirrer shall be accessible to the outside through a coupler oflow thermal conductivity. The stirrer speed shall remainconstant to minimize any temperature variations due to stirring.Continuous stir
28、ring for 10 min shall not raise the calorimetertemperature more than 0.01C when starting with identicaltemperatures in the calorimeter, test area and jacket. Forcalorimeters having a bucket it can be a separate component orintegral component of the bomb. The vessel shall be of suchconstruction that
29、the environment of the calorimeters entireouter boundaries can be maintained at a uniform temperature.6.5 JacketA container with the inner perimeter main-tained at constant temperature 60.1C (isoperibol) or at thesame temperature 60.1C as the calorimeter vessel (adiabatic)during the test. To minimiz
30、e convection, the sides, top andbottom of the calorimeter vessel shall not be more than 10 mmfrom the inner surface of the jacket. Mechanical supports forthe calorimeter vessel shall be of low thermal conductivity.6.6 Thermometers:6.6.1 Automated CalorimetersPlatinum resistance or lin-ear thermistor
31、 thermometers shall be capable of measuring tothe nearest 0.0001C. Thermometer calibration shall be trace-able to a recognized certifying agency.6.6.2 Manual Calorimeters:6.6.2.1 Platinum Resistance or Linear Thermistor Ther-mometers shall be capable of measuring to the nearest0.0001C. Thermometer c
32、alibration shall be traceable to arecognized certifying agency.6.6.2.2 Liquid-in-Glass ThermometersConforming to therequirements for thermometers 56C, 116C, or 117C as pre-scribed in Specification E1. Thermometers 56C shall becalibrated at intervals no larger than 2.0C over the entiregraduated scale
33、. The maximum difference in correction be-tween any two calibration points shall be no more than 0.02C.Thermometers 116C and 117C shall be calibrated at intervalsno larger than 0.5C over the entire graduated scale. Themaximum difference in correction between any two calibrationpoints shall not be mo
34、re than 0.02C.6.6.2.3 Beckman Differential Thermometer(Glass en-closed scale, adjustable), having a range of approximately 6Cin 0.01C subdivisions reading upward and conforming to therequirements for Thermometer 115C, as prescribed in Specifi-cation E1. The thermometer shall be calibrated at interva
35、ls nolarger than 1C over the entire graduated scale. The maximumdifference in the correction between any two calibration pointsshall be less than 0.02C.6.6.2.4 Thermometer AccessoriesA magnifier is requiredfor reading liquid-in-glass thermometers to one tenth of thesmallest scale division. The magni
36、fier shall have a lens andholder designed so as to minimize errors as a result of parallax.D58650726.7 Sample HolderAn open crucible of platinum, quartz,or base metal alloy. Before use in the calorimeter, heat treatbase metal crucibles for a minimum of4hat500C to ensurethe crucible surface is comple
37、tely oxidized. Base metal alloycrucibles are acceptable, if after three preliminary firings, theweight does not change by more than 0.0001 g.6.8 Ignition FuseIgnition fuse of 100-mm length and0.16-mm (No. 34 B filling the calorimeter vessel; firing theignition circuit; recording calorimeter temperat
38、ures before,during, and after the test; recording the balance weights; andcarrying out all necessary corrections and calculations.6.11 Crucible LinerQuartz fiber or alundum for lining thecrucible to promote complete combustion of samples that donot burn completely during the determination of the cal
39、orificvalue.37. Reagents7.1 Reagent WaterConforming to conductivity require-ments for Type II of Specification D 1193 for preparation ofreagents and washing of the bomb interior.7.2 Purity of ReagentsUse reagent grade chemicals con-forming to the specification of the Committee on AnalyticalReagents
40、of the American Chemical Society in all tests.47.3 Benzoic AcidStandard (C6H5COOH)Pellets madefrom benzoic acid available from the National Institute ofStandards and Technology (NIST) or benzoic acid calibratedagainst NIST standard material. The calorific value of benzoicacid, for use in the calibra
41、tion calculations, shall be traceable toa recognized certificate value.7.4 OxygenManufactured from liquid air, guaranteed tobe greater than 99.5 % pure, and free of combustible matter.Oxygen made by the electrolytic process contains smallamounts of hydrogen rendering it unfit unless purified bypassa
42、ge over copper oxide at 500C.7.5 Titration IndicatorMethyl orange, methyl red, ormethyl purple for indicating the end point when titrating theacid formed during combustion. The same indicator shall beused for both calibration and calorific value determinations.7.6 Standard SolutionSodium carbonate (
43、Na2CO3)orother suitable standard solution. Dissolve 3.757 g of sodiumcarbonate, dried for 24 h at 105C in water, and dilute to 1 L.One millilitre of this solution is equivalent to 4.2 J (1.0 calorie)in the acid titration.8. Hazards8.1 The following precautions are recommended for safecalorimeter ope
44、ration. Additional precautions are noted inPractice E 144. Also consult the calorimeter equipment manu-facturers installation and operating instructions before usingthe calorimeter.8.1.1 The mass of sample and any combustion aid as well asthe pressure of the oxygen admitted to the bomb shall notexce
45、ed the bomb manufacturers specifications.8.1.2 Inspect the bomb parts carefully after each use.Replace cracked or significantly worn parts. Replace O-ringsand valve seats in accordance with manufacturers instruction.For more details, consult the manufacturer.8.1.3 Equip the oxygen supply cylinder wi
46、th an approvedtype of safety device, such as a relief valve, in addition to theneedle valve and pressure gage used in regulating the oxygenfeed to the bomb. Valves, gages, and gaskets shall meetindustry safety codes. Suitable reducing valves and adaptersfor 3- to 4-MPa (300- to 500-psig) discharge p
47、ressure can beobtained from commercial sources of compressed gas equip-ment. Check the pressure gage annually for accuracy or afterany accidental over pressures that reach maximum gagepressure.8.1.4 During ignition of a sample, the operator shall notextend any portion of the body over the calorimete
48、r.8.1.5 Do not fire the bomb if the bomb has been dropped orturned over after loading.8.1.6 Do not fire the bomb if there is evidence of gasleakage when the bomb is submerged in the calorimeter vessel.8.1.7 For manually operated calorimeters, the ignitionswitch shall be depressed only long enough to
49、 fire the charge.9. Sample9.1 The analysis sample is the material pulverized to pass250-m (No. 60) sieve, prepared in accordance with eitherPractice D 346 for coke or Method D 2013 for coal.10. Determination of the Heat Capacity of theCalorimeter10.1 SampleWeigh 0.8 to 1.2 g of benzoic acid into asample holder. Record sample weight to the nearest 0.0001 g.10.2 Preparation of Bomb:10.2.1 Rinse the bomb with water to wet internal seals andsurface areas of the bomb or precondition the calorimeteraccording to the manufacturers ins
