1、Designation: D2598 12Standard Practice forCalculation of Certain Physical Properties of LiquefiedPetroleum (LP) Gases from Compositional Analysis1This standard is issued under the fixed designation D2598; the number immediately following the designation indicates the year oforiginal adoption or, in
2、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. Scope*1.1 This practice covers, by compositional analysis, theapproximate determination of th
3、e following physical charac-teristics of commercial propane, special-duty propane, com-mercial propane/butane mixtures, and commercial butane (cov-ered by Specification D1835): vapor pressure, relative density,and motor octane number (MON).1.1.1 This practice is not applicable to any product exceed-
4、ing specifications for nonvolatile residues. (See Test MethodD2158.)1.1.2 For calculating motor octane number, this practice isapplicable only to mixtures containing 20 % or less of propene.1.1.3 For calculated motor octane number, this practice isbased on mixtures containing only components shown i
5、n Table1.1.2 The values stated in SI units are to be regarded asstandard. The values given in parentheses are for informationonly.1.2.1 ExceptionMotor octane number and relative densityare given in MON numbers and dimensionless units, respec-tively.2. Referenced Documents2.1 ASTM Standards:2D1267 Te
6、st Method for Gage Vapor Pressure of LiquefiedPetroleum (LP) Gases (LP-Gas Method)D1657 Test Method for Density or Relative Density of LightHydrocarbons by Pressure HydrometerD1835 Specification for Liquefied Petroleum (LP) GasesD2158 Test Method for Residues in Liquefied Petroleum(LP) GasesD2163 Te
7、st Method for Analysis of Liquefied Petroleum(LP) Gases and Propene Concentrates by Gas Chromatog-raphyD2421 Practice for Interconversion of Analysis of C5andLighter Hydrocarbons to Gas-Volume, Liquid-Volume, orMass Basis2.2 Australian Liquefied Petroleum Gas Association Publi-cation:3Liquefied Petr
8、oleum Gas for Automotive Use Specification2.3 Gas Processors Suppliers Association:4GPSA Engineering Data Book, 12th Edition, 20043. Summary of Practice3.1 The composition of a sample of LP-gas is obtained byusing Test Method D2163 or other acceptable method. Fromthe analysis (expressed in liquid vo
9、lume percent), the vaporpressure, relative density, and motor octane number of thesample may be determined.3.2 Conversion of a compositional analysis from mole, gasvolume, or weight basis to liquid volume is obtained by usingPractice D2421 or other suitable method.4. Significance and Use4.1 Vapor pr
10、essure is an important specification property ofcommercial propane, special duty propane, propane/butanemixtures, and commercial butane that assures adequatevaporization, safety, and compatibility with commercial appli-ances. Relative density, while not a specification criterion, isnecessary for det
11、ermination of filling densities and custodytransfer. The motor octane number (MON) is useful in deter-mining the products suitability as a fuel for internal combus-tion engines.5. Calculation5.1 Calculated LP-Gas Vapor Pressure (see Test MethodD1267):1This practice is under the jurisdiction of ASTM
12、Committee D02 on PetroleumProducts and Lubricants and is the direct responsibility of Subcommittee D02.H0 onLiquefied Petroleum Gas.Current edition approved Nov. 1, 2012. Published February 2013. Originallyapproved in 1967. Last previous edition approved in 2007 as D259802(2007).DOI: 10.1520/D2598-1
13、2.2For 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.3Available from Australian Liquefied Petroleum Gas Associat
14、ion Limited, ABN11002703951, 30 George Street, Redfern NSW 2016, http:/.au/site/4Available from Gas Processors SuppliersAssociation (GPSA), 6526 E. 60th St.,Tulsa, OK 74145, http:/www.gpsa.gpaglobal.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 10
15、0 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.1.1 Calculate the partial gage vapor pressure due to eachcomponent in the mixture as follows:Partial gage vapor pressure 5 vp 3 C!/100where:vp = vapor pressure factor of specific component at 37.8C(100F) (see Table 1
16、), andC = liquid volume percent of component in the mixture.5.1.2 Add the partial gage vapor pressures due to allcomponents, rounding to the nearest 7 kPa (1 psi). The total isreported as the LP-gas vapor pressure of the sample, kPa gageat 37.8C (100F).5.2 Calculated Relative Density (see Test Metho
17、d D1657):5.2.1 Calculate the relative mass of each component in themixture as follows:Relative mass of component 5 sg 3 C!/100where:sg = relative density of the pure component at 15.6C(60F) (see Table 1), andC = liquid volume percent of component in the mixture.5.2.2 Add the relative mass of all com
18、ponents, rounding thetotal to three decimal places. The total is reported as therelative density of the mixture.5.3 Calculated Motor Octane Number (see ASTM DataSeries DS 4B.5).5.3.1 Using only the components and values in Table 1,calculate the partial motor octane number of each componentin the mix
19、ture to the nearest 0.1 MON as follows:Partial motor octane number of component 5 m 3 C!/100where:m = motor octane number of component (see Table 1), andC = liquid volume percent of component in mixture.5.3.2 Add the partial motor octane numbers of all compo-nents determined in 5.3.1 and round the t
20、otal to the nearestone-half number. The total is reported as the calculated motoroctane number of the mixture.6. Keywords6.1 butane; calculated physical properties; liquefied petro-leum gases; motor octane number; propane; relative density;vapor pressure5DS 4B, Physical Constants of Hydrocarbon and
21、Non-HydrocarbonCompounds, ASTM International, W. Conshohocken, PA, 1987.TABLE 1 Factors for Determining the Physical Characteristics of LP-GasesAComponentVapor Pressure BlendFactor, kPa-gage(PSIG) at 37.8C (100F)Relative Density at15.6C (60F)MON Blend ValueMethane 17547 (2545) 0.3 . . .Ethane 4213 (
22、611) 0.3563 100.7Ethene (Ethylene) 8720 (1265) 0.37 75.6Propane 1200 (174) 0.5072 97.1Propene (Propylene) 1466 (213) 0.5226 84.9Methylpropane (Isobutane) 400 (58) 0.5629 97.6n-Butane 255 (37) 0.5842 89.6t-2-Butene 242 (35) 0.6099 1-Butene 328 (48) 0.6004 80.82-Methylpropene (Isobutylene) 340 (49) 0.
23、6004 c-2-Butene 216 (31) 0.6275 83.52,2-Dimethylpropane (Neopentane) 152 (22) 0.5961 80.2Cyclopentane -33 (-4.7) 0.7503 84.92-Methylbutane (Isopentane) 40 (5.8) 0.6251 90.3n-Pentane 6.4 (0.9) 0.6307 62.6n-Hexane -67 (-9.7) 0.6641 26.0ASome constants for vapor pressure and motor octanes are empirical
24、 values to be used only in the calculation procedures described in this practice. References arelocated in Appendix X1.D2598 122APPENDIXX1. SOURCES OF PHYSICAL CONSTANT DATAX1.1 See Table X1.1.SUMMARY OF CHANGESSubcommittee D02.H0 has identified the location of selected changes to this standard sinc
25、e the last issue(D259802(2007) that may impact the use of this standard.(1) Updated 1.1 to include butane and propane/butane mix-tures.(2) Added 2.2 and 2.3 in Referenced Documents.(3) Added butane to 4.1.(4) Updated 5.3.1 and 5.3.2.(5) Updated Section 6.(6) Modified Table 1.(7) Added Appendix X1.AS
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27、ntirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standards
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29、 on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or
30、 at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).TABLE X1.1 Sources of Physical Constant DataComponent Vapor Pressure B
31、lend FactorARelative Mass MON Blend ValueMethaneBCEthaneBDBEthene (Ethylene)EFEPropaneDDCPropene (Propylene)Methylpropane (Isobutane)n-Butanet-2-ButeneDD1-Butene2-Methylpropene (Isobutylene) c-2-ButeneDDC2,2-Dimethylpropane (Neopentane)Cyclopentane2-Methylbutane (Isopentane)n-Pentanen-HexaneAVapor p
32、ressure values were converted from atmospheric to gage by the following equations: PSIG = PSIA 14.7; kPa(G) = kPa(A)-101.BEmpirical values for use in D2598 calculations.CGPSA Engineering Data Book, 12th Edition, 2004.DTRC (formerly the Thermodynamic Research Center), NIST, Boulder, CO, 2012.EAustral
33、ian Liquefied Petroleum Gas Association Publication, Liquefied Petroleum Gas for Automotive Use Specification.FThe relative density of ethylene is estimated, and consistent with the historical value in Practice D2421-95. Later revisions of Practice D2421 used a theoretical, calculatedvalue from GPA 2145-00. Uncertainties in the equations of state used in the calculation for ethylene at typical pressures and temperatures of LPG caused GPA to laterretract that value.D2598 123
