1、Designation: D240 17Standard 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)D1552 Test Method for Sulfur in
7、Petroleum Products byHigh Temperature Combustion and Infrared (IR) Detec-tion or Thermal Conducitivity Detection (TCD)D2622 Test Method for Sulfur in Petroleum Products byWavelength Dispersive X-ray Fluorescence SpectrometryD3120 Test Method for Trace Quantities of Sulfur in LightLiquid Petroleum Hy
8、drocarbons by Oxidative Microcou-lometryD3701 Test Method for Hydrogen Content of AviationTurbine Fuels by Low Resolution Nuclear MagneticResonance SpectrometryD4294 Test Method for Sulfur in Petroleum and PetroleumProducts by Energy Dispersive X-ray Fluorescence Spec-trometryD4809 Test Method for H
9、eat of Combustion of LiquidHydrocarbon Fuels by Bomb Calorimeter (PrecisionMethod)D5453 Test Method for Determination of Total Sulfur inLight Hydrocarbons, Spark Ignition Engine Fuel, DieselEngine Fuel, and Engine Oil by Ultraviolet FluorescenceD7171 Test Method for Hydrogen Content of Middle Dis-ti
10、llate Petroleum Products by Low-Resolution PulsedNuclear Magnetic Resonance SpectroscopyE1 Specification for ASTM Liquid-in-Glass ThermometersE200 Practice for Preparation, Standardization, and Storageof Standard and Reagent Solutions for Chemical Analysis3. Terminology3.1 Definitions:3.1.1 gross he
11、at of combustion, Qg (MJ/kg), nthe quantityof energy released when a unit mass of fuel is burned in aconstant volume enclosure, with the products being 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 element
12、s carbon, hydrogen, nitrogen, andsulfur. The products of combustion, in oxygen, are gaseouscarbon dioxide, nitrogen oxides, sulfur dioxide, and liquidwater. 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
13、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, including water, beinggaseous.3.1.2.1 DiscussionThe fuel can be either liquid or solid,1This test method is under the jurisdiction of ASTM Committee D02 o
14、nPetroleum 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 Jan. 1, 2017. Published January 2017. Originallyapproved in 1957. Last previous edition approved in 2014 as D24
15、0 14. DOI:10.1520/D0240-17.2For 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.*A Summary of Changes section appe
16、ars at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Princip
17、les for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1and contain only the elements carbon, hydrogen, oxygen,nitrogen, and sulfur. The products of combustion, in oxygen,are carbon dioxide, nit
18、rogen oxides, sulfur dioxide, and water,all in the gaseous state. In this procedure, the combustion takesplace at a constant pressure of 101.325 kPa (1 atm), and 25 Cis the initial temperature of the fuel and the oxygen, and thefinal temperature of the products of combustion.3.1.3 The following rela
19、tionships may be used for convert-ing between units:1 calit(International Table calorie) = 4.1868 J1Btuit(International Table British thermal unit) = 1055.05585262 J andtypically rounded to 1055.056 for practical use1 calit/g = 0.0041868 MJ kg1Btuit/lb = 0.002326 MJ kg3.2 Definitions of Terms Specif
20、ic 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 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
21、 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 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 com
22、bustion 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 unit of measurement employed in this test methodis the joule with the heat of combustion reported in megajoules perkilogram.4. Summar
23、y 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 of combustion is com-puted from temperature observations before, during, and aftercombustion, with proper allowance for thermochemica
24、l 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 Temperatures can be recorded in either degreesFahrenheit or ohms or other units when using electric ther-mometers. Use the same units in all c
25、alculations, includingstandardization.4.1.2 Time is expressed in calculations in minutes anddecimal fractions thereof. It may be measured in minutes andseconds.4.1.3 Masses are measured in grams and no buoyancycorrections are applied.5. Significance and Use5.1 The heat of combustion is a measure of
26、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 heat of combustion as determined by this testmethod is designated as one of the chemical and physicalrequirements of both commercial a
27、nd 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 foruse in weight-limited craft such as airplanes, surface effectvehicles, and hydrofoils. The range of such craft betweenrefueling is
28、 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 Annex A1.7. Reagents7.1 Benzoic Acid, Standard4Benzoic acid powder must becompressed into a tablet or pellet before weighing. Benzoi
29、cacid pellets for which the heat of combustion has beendetermined by comparison with the National Bureau of Stan-dards sample are obtainable commercially for those laborato-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 Oxy
30、genCommerical oxygen produced from liquid aircan be used without purification. If purification is necessary,see A1.11 (WarningOxygen vigorously accelerates combus-tion. See A3.2.).7.6 Pressure-Sensitive TapeCellophane tape 38 mm(112 in.) wide, free of chlorine and sulfur.7.7 Alkali, Standard Solutio
31、n: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 andadjust to 0.0866 mol/L as described in Practice E200(WarningCorrosive. Can cause severe burns or blindness.Evolution of heat produces a vi
32、olent 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 dilute to 1 L.Standardize with potassium acid phthalate and adjust to0.03625 mol/L as described in Practice E200.3Supporting data (derivat
33、ion of equations) have been 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
34、. 39.D240 1727.8 2,2,4-Trimethylpentane (isooctane), Standard5(WarningExtremely flammable. Harmful if inhaled. Vaporsmay cause flash fire. See Annex A3.3.)8. Standardization8.1 Determine the Energy Equivalent of the CalorimeterAverage not less than six tests using standard benzoic acid.6These tests
35、should be spaced over a period of not less thanthree days. Use not less than 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
36、 corrections for nitric acid (HNO3) and firingwire as described in 10.3 and 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 benzo
37、ic acid sample, g,t = corrected temperature rise, as calculated in 10.1 or10.2,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
38、 check on bothcalorimeter and operating technique.8.2 Checking the Calorimeter 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
39、 within this range, the technique of handling thesample may have to be changed (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-Sensit
40、ive Tape orGelatin/Mineral OilDetermine the heat of combustion ofeither the 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
41、 theheat of combustion as follows:Qpst5 t 3W 2 e1!/1000 a (4)where:Qpst= heat 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
42、of formation of HNO3, MJ, anda = mass of the pressure-sensitive tape or gelatin 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 weigh
43、t of sample (in-cluding any auxiliary fuel) so that the temperature rise pro-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 es
44、timated as follows:m 5 26.454/Qs(5)where:m = mass of sample, g, andQs= MJ/kg.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
45、For highly volatile fluids, reduce loss with use of tapeor gelatin capsule mineral 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
46、 holder: (8) describes a gelatin sample holder.9.1.2 TapePlace a piece of pressure-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
47、flap arrangement. Weigh the cup and tape. Remove fromthe balance with forceps. 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
48、of combustion of the sample, MJ/kg,andD = density, kg/m3, of the sample.9.1.2.1 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
49、spatula. Reweigh thecup with the tape and sample. Take care throughout theweighing 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 capsule should only be handled with forceps.Add the5Obtainable from the National Institute of Standards Technology as standardsample No. 217b.6Jessup, R. S., “Precise Measu
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