1、Designation: D240 14Standard Test Method forHeat of Combustion of Liquid Hydrocarbon Fuels by BombCalorimeter1This standard is issued under the fixed designation D240; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of las
2、t revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope*1.1 This test method covers the determ
3、ination of the heat ofcombustion of liquid hydrocarbon fuels ranging in volatilityfrom that of light distillates to that of residual fuels.1.2 Under normal conditions, this test method is directlyapplicable to such fuels as gasolines, kerosines, Nos. 1 and 2fuel oil, Nos. 1-D and 2-D diesel fuel and
4、 Nos. 0-GT, 1-GT,and 2-GT gas turbine fuels.1.3 This test method is not as repeatable and not asreproducible as Test Method D4809.1.4 The values stated in SI units are to be regarded asstandard. The values in parentheses are for information only.1.5 This standard does not purport to address all of t
5、hesafety 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. For specific hazardstatements, see Sections 7 and 9 and A1.10 and An
6、nex A3.2. Referenced Documents2.1 ASTM Standards:2D129 Test Method for Sulfur in Petroleum Products (Gen-eral High Pressure Decomposition Device Method)D1018 Test Method for Hydrogen In Petroleum FractionsD1266 Test Method for Sulfur in Petroleum Products (LampMethod)D2622 Test Method for Sulfur in
7、Petroleum Products byWavelength Dispersive X-ray Fluorescence SpectrometryD3120 Test Method for Trace Quantities of Sulfur in LightLiquid Petroleum Hydrocarbons by Oxidative Microcou-lometryD3701 Test Method for Hydrogen Content of AviationTurbine Fuels by Low Resolution Nuclear MagneticResonance Sp
8、ectrometryD4294 Test Method for Sulfur in Petroleum and PetroleumProducts by Energy Dispersive X-ray Fluorescence Spec-trometryD4809 Test Method for Heat of Combustion of LiquidHydrocarbon Fuels by Bomb Calorimeter (PrecisionMethod)D5453 Test Method for Determination of Total Sulfur inLight Hydrocar
9、bons, Spark Ignition Engine Fuel, DieselEngine Fuel, and Engine Oil by Ultraviolet FluorescenceD7171 Test Method for Hydrogen Content of Middle Dis-tillate Petroleum Products by Low-Resolution PulsedNuclear Magnetic Resonance SpectroscopyE1 Specification for ASTM Liquid-in-Glass ThermometersE200 Pra
10、ctice for Preparation, Standardization, and Storageof Standard and Reagent Solutions for Chemical Analysis3. Terminology3.1 Definitions:3.1.1 gross heat of combustion, Qg (MJ/kg), nthe quantityof energy released when a unit mass of fuel is burned in aconstant volume enclosure, with the products bein
11、g gaseous,other than water that is condensed to the liquid state.3.1.1.1 DiscussionThe fuel can be either liquid or solid,and contain only the elements carbon, hydrogen, nitrogen, andsulfur. The products of combustion, in oxygen, are gaseouscarbon dioxide, nitrogen oxides, sulfur dioxide, and liquid
12、water. In this procedure, 25 C is the initial temperature of thefuel and the oxygen, and the final temperature of the productsof combustion.3.1.2 net heat of combustion, Qn (MJ/kg), nthe quantity ofenergy released when a unit mass of fuel is burned at constantpressure, with all of the products, incl
13、uding water, beinggaseous.3.1.2.1 DiscussionThe fuel can be either liquid or solid,and contain only the elements carbon, hydrogen, oxygen,nitrogen, and sulfur. The products of combustion, in oxygen,are carbon dioxide, nitrogen oxides, sulfur dioxide, and water,all in the gaseous state. In this proce
14、dure, the combustion takes1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.05 on Properties of Fuels, Petroleum Coke and Carbon Material.Current edition approved Oct. 1, 2014. Publ
15、ished October 2014. Originallyapproved in 1957. Last previous edition approved in 2009 as D240 09. DOI:10.1520/D0240-14.2For 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
16、 to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1place at a constant pressure of 101.325 kPa (1 atm), and 25 Ci
17、s the initial temperature of the fuel and the oxygen, and thefinal temperature of the products of combustion.3.1.3 The following relationships may be used for convert-ing between units:1 calit(International Table calorie) = 4.1868 J1Btuit(International Table British thermal unit) = 1055.05585262 J a
18、ndtypically rounded to 1055.056 for practical use1 calit/g = 0.0041868 MJ/kg1Btuit/lb = 0.002326 MJ/kg3.2 Definitions of Terms Specific to This Standard:3.2.1 energy equivalent, n(effective heat capacity or waterequivalent) of the calorimeter is the energy required to raise thetemperature one degree
19、 Celsius expressed as MJ/C.1 MJ/kg 5 1000 J/g (1)In SI, the unit of heat of combustion has the dimensionJ/kg, but for practical use a multiple is more convenient. TheMJ/kg is customarily used for the representation of heats ofcombustion of petroleum fuels. The net heat of combustionis related to the
20、 gross heat of combustion by the followingequation:Qnnet, 25 C! 5 Qggross, 25 C! 2 0.2122 3H (2)where:Qn(net, 25 C) = net heat of combustion at constantpressure, MJ/kg,Qg(gross, 25 C) = gross heat of combustion at constantvolume, MJ/kg, andH = mass percent of hydrogen in thesample.3NOTE 1The energy
21、unit of measurement employed in this test methodis the joule with the heat of combustion reported in megajoules perkilogram.4. Summary of Test Method4.1 Heat of combustion is determined in this test method byburning a weighed sample in an oxygen bomb calorimeterunder controlled conditions. The heat
22、of combustion is com-puted from temperature observations before, during, and aftercombustion, with proper allowance for thermochemical andheat transfer corrections. Either isothermal or adiabatic calo-rimeter jackets can be used.4.1.1 Temperatures can be measured in degrees Celsius.4.1.1.1 Temperatu
23、res can be recorded in either degreesFahrenheit or ohms or other units when using electric ther-mometers. Use the same units in all calculations, includingstandardization.4.1.2 Time is expressed in calculations in minutes anddecimal fractions thereof. It may be measured in minutes andseconds.4.1.3 M
24、asses are measured in grams and no buoyancycorrections are applied.5. Significance and Use5.1 The heat of combustion is a measure of the energyavailable from a fuel. A knowledge of this value is essentialwhen considering the thermal efficiency of equipment forproducing either power or heat.5.2 The h
25、eat of combustion as determined by this testmethod is designated as one of the chemical and physicalrequirements of both commercial and military turbine fuels andaviation gasolines.5.3 The mass heat of combustion, the heat of combustionper unit mass of fuel, is a critical property of fuels intended
26、foruse in weight-limited craft such as airplanes, surface effectvehicles, and hydrofoils. The range of such craft betweenrefueling is a direct function of the heat of combustion anddensity of the fuel.6. Apparatus6.1 Test Room, Bomb, Calorimeter, Jacket, Thermometers,and Accessories, as described in
27、 Annex A1.7. Reagents7.1 Benzoic Acid, Standard4Benzoic acid powder must becompressed into a tablet or pellet before weighing. Benzoicacid pellets for which the heat of combustion has beendetermined by comparison with the National Bureau of Stan-dards sample are obtainable commercially for those lab
28、orato-ries not equipped to pellet benzoic acid.7.2 Gelatin Capsules.7.3 Methyl Orange or Methyl Red Indicator.7.4 Mineral Oil.7.5 OxygenCommerical oxygen produced from liquid aircan be used without purification. If purification is necessary,see A1.11 (WarningOxygen vigorously accelerates combus-tion
29、. See A3.2.).7.6 Pressure-Sensitive TapeCellophane tape 38 mm(112 in.) wide, free of chlorine and sulfur.7.7 Alkali, Standard Solution:7.7.1 Sodium Hydroxide Solution (0.0866 mol/L)Dissolve 3.5 g of sodium hydroxide (NaOH) in water anddilute to 1 L. Standardize with potassium acid phthalate andadjus
30、t to 0.0866 mol/L as described in Practice E200(WarningCorrosive. Can cause severe burns or blindness.Evolution of heat produces a violent reaction or eruption upontoo rapid mixture with water. See Annex A3.1.)7.7.2 Sodium Carbonate Solution (0.03625 mol/L)Dissolve 3.84 g of Na2CO3in water and dilut
31、e to 1 L.Standardize with potassium acid phthalate and adjust to0.03625 mol/L as described in Practice E200.7.8 2,2,4-Trimethylpentane (isooctane), Standard5(WarningExtremely flammable. Harmful if inhaled. Vaporsmay cause flash fire. See Annex A3.3.)3Supporting data (derivation of equations) have be
32、en filed at ASTM Interna-tional Headquarters and may be obtained by requesting Research Report RR:RR:D02-1346.4Available from National Institute of Standards and Technology (NIST), 100Bureau Dr., Stop 1070, Gaithersburg, MD 20899-1070, http:/www.nist.gov asstandard sample No. 39.5Obtainable from the
33、 National Institute of Standards Technology as standardsample No. 217b.D240 1428. Standardization8.1 Determine the Energy Equivalent of the CalorimeterAverage not less than six tests using standard benzoic acid.6These tests should be spaced over a period of not less thanthree days. Use not less than
34、 0.9 g nor more than 1.1 g ofstandard benzoic acid (C6H6COOH). Make each determinationaccording to the procedure described in Section 9 and computethe corrected temperature rise, t, as described in 10.1 or 10.2.Determine the corrections for nitric acid (HNO3) and firingwire as described in 10.3 and
35、substitute in the followingequation:W 5 Q 3g1e11e2!/t (3)where:W = energy equivalent of calorimeter, MJ/C,Q = heat of combustion of standard benzoic acid, MJ/g,calculated from the certified value,g = weight of standard benzoic acid sample, g,t = corrected temperature rise, as calculated in 10.1 or10
36、.2,C,e1= correction for heat of formation of nitric acid, MJ, ande2= correction for heat of combustion of firing wire, MJ.8.1.1 Repeat the standardization tests after changing anypart of the calorimeter and occasionally as a check on bothcalorimeter and operating technique.8.2 Checking the Calorimet
37、er for Use with Volatile FuelsUse 2,2,4-trimethylpentane to determine whether the resultsobtained agree with the certified value (47.788 MJ/kg, weightin air) within the repeatability of the test method. If results donot come within this range, the technique of handling thesample may have to be chang
38、ed (Annex A1.8). If this is notpossible or does not correct the error, run a series of tests using2,2,4-trimethylpentane to establish the energy equivalent foruse with volatile fuels.8.3 Heat of Combustion of Pressure-Sensitive Tape orGelatin/Mineral OilDetermine the heat of combustion ofeither the
39、pressure-sensitive tape or 0.5 g gelatin capsule/mineral oil in accordance with Section 9 using about 1.2 g oftape or 0.5 g gelatin capsule/mineral oil and omitting thesample. Make at least three determinations and calculate theheat of combustion as follows:Qpst5 t 3W 2 e1!/1000 a (4)where:Qpst= hea
40、t of combustion of the pressure-sensitive tape ormineral oil, MJ/kg,t = corrected temperature rise, as calculated in accor-dance with 10.1 or 10.2,C,W = energy equivalent of the calorimeter, MJ/C,e1= correction for the heat of formation of HNO3, MJ, anda = mass of the pressure-sensitive tape or gela
41、tin capsule/mineral oil, g.Average the determinations, and redetermine the heat ofcombustion of the tape or gelatin capsule/mineral oil whenevera new roll or batch is started.9. Procedure9.1 Weight of SampleControl the weight of sample (in-cluding any auxiliary fuel) so that the temperature rise pro
42、-duced by its combustion will be equal to that of 0.9 g to 1.1 gof benzoic acid (Note 2). Weigh the sample to the nearest0.1 mg.NOTE 2If the approximate heat of combustion of the sample is known,the required weight can be estimated as follows:m 5 26.454/Qs(5)where:m = mass of sample, g, andQs= MJ/kg
43、.Some fuels contain water and particulate matter (ash) thatwill degrade calorimetric values. If the heat of combustion isrequired on a clean fuel, filter the sample to remove free waterand insoluble ash before testing.9.1.1 For highly volatile fluids, reduce loss with use of tapeor gelatin capsule m
44、ineral oil.NOTE 3Acceptable procedures for handling volatile liquids includethose described in the reports referenced at the end of this test method.References (1-6) describe glass sample holders: (7) describes a metalsample holder: (8) describes a gelatin sample holder.9.1.2 TapePlace a piece of pr
45、essure-sensitive tape acrossthe top of the cup, trim around the edge with a razor blade, andseal tightly. Place 3 mm by 12 mm strip of tape creased in themiddle and sealed by one edge in the center of the tape disk togive a flap arrangement. Weigh the cup and tape. Remove fromthe balance with forcep
46、s. Fill a hypodermic syringe with thesample. The volume of sample can be estimated as follows:V 5 W 30.00032!/Q 3D! (6)where:V = volume of sample to be used, mL,W = energy equivalent of calorimeter, J/C,Q = approximate heat of combustion of the sample, MJ/kg,andD = density, kg/m3, of the sample.9.1.
47、2.1 Add the sample to the cup by inserting the tip of theneedle through the tape disk at a point so that the flap of tapewill cover the puncture upon removal of the needle. Seal downthe flap by pressing lightly with a metal spatula. Reweigh thecup with the tape and sample. Take care throughout thewe
48、ighing and filling operation to avoid contacting the tape orcup with bare fingers. Place the cup in the curved electrode andarrange the fuse wire so that the central portion of the looppresses down on the center of the tape disk.9.1.3 Gelatin/Mineral OilWeigh the cup and gelatin cap-sule. The capsul
49、e should only be handled with forceps.Add thesample to the capsule. Reweigh the cup with capsule andsample. If poor combustion is expected with the capsule, addseveral drops of mineral oil on the capsule and reweigh the cup6Jessup, R. S., “Precise Measurement of Heat of Combustion with a BombCalorimeter,” NBS Monograph 7, U. S. Government Printing Office.D240 143and contents. Place the cup in the curved electrode and arrangethe fuse wire so that the central portion of the loop contacts thecapsule and oil.9.2 Water in BombAdd 1.0 mL of
