1、BSI Standards PublicationBS 8609:2014Natural gas Calculation ofcarbon dioxide emissionfactors from compositionPublishing and copyright informationThe BSI copyright notice displayed in this document indicates when the documentwas last issued. The British Standards Institution 2014Published by BSI Sta
2、ndards Limited 2014ISBN 978 0 580 83913 9ICS 75.060The following BSI references relate to the work on this document:Committee reference PTI/15Draft for comment 14/30287938 DCPublication historyFirst published July 2014Amendments issued since publicationDateText affectedBS 8609:2014 BRITISH STANDARDC
3、ontentsForeword ii1 Scope 12 Normative references 13 Terms, definitions and units 14 Calculation of the carbon dioxide emission factor 45 Uncertainty of calculation 56 Expression of results 7AnnexesAnnex A (informative) Example of calculation 8Bibliography 12List of tablesTable A.1 Example analysis
4、report for natural gas 8Table A.2 Component data 9Table A.3 Ancillary data 9Table A.4 Correlation matrix of molar mass 10Table A.5 Carbon dioxide emission factors and their uncertainties, excludingmole fraction correlation 10Table A.6 Standard uncertainties of normalized mole fractions and elements
5、ofthe mole fraction correlation coefficient matrix 11Table A.7 Carbon dioxide emission factors and their uncertainties, includingmole fraction correlation 11Table A.8 Standard uncertainties of carbon dioxide emission factors compositional uncertainty only 11Summary of pagesThis document comprises a
6、front cover, an inside front cover, pages i to ii,pages 1 to 12, an inside back cover and a back cover.BRITISH STANDARD BS 8609:2014 The British Standards Institution 2014 iForewordPublishing informationThis British Standard is published by BSI Standards Limited, under licence fromThe British Standa
7、rds Institution, and came into effect on 31 July 2014. It wasprepared by Technical Committee, PTI/15, Natural Gas and Gas Analysis. A list oforganizations represented on this committee can be obtained on request to itssecretary.Relationship with other publicationsThe methods of calculation in this B
8、ritish Standard require a value of the atomicindex for carbon of each component comprising the gas mixture, together withthe relevant molar property of the gas mixture. All of these values are eitherobtained from or calculated according to BS EN ISO 6976.The method of calculation in this British Sta
9、ndard is applicable to any gasmixture for which BS EN ISO 6976 is applicable.Use of this documentIt has been assumed in the preparation of this British Standard that theexecution of its provisions will be entrusted to appropriately qualified andexperienced people, for whose use it has been produced.
10、Presentational conventionsThe provisions of this standard are presented in roman (i.e. upright) type. Itsmethods are expressed as a set of instructions, a description, or in sentences inwhich the principal auxiliary verb is “shall”.Commentary, explanation and general informative material is presente
11、d insmaller italic type, and does not constitute a normative element.Contractual and legal considerationsThis publication does not purport to include all the necessary provisions of acontract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity
12、 from legalobligations.BRITISH STANDARDBS 8609:2014ii The British Standards Institution 20141 ScopeThis British Standard gives methods for the calculation of the carbon dioxideemission factor of natural gases, natural gas substitutes and other combustiblegaseous fuels, when the composition of the ga
13、s by mole fraction is known. Themethod provides for the calculation of the carbon dioxide emission factor at thecommonly used reference conditions of temperature and pressure and on thefour common quantity bases: mole; mass; volume (at the reference conditions of temperature and pressure); and energ
14、y (gross or net).Annex A provides example calculations for carbon dioxide emission factors on allthe above bases and their uncertainties.This standard requires use of complete compositional data in the form of molefractions that, by definition, sum to unity. If this is not so then the raw molefracti
15、on data is to be normalized and the normalized mole fractions and theiruncertainties recalculated. Guidance on such data processing is provided inBS EN ISO 6974-1 and BS EN ISO 6974-2.If the compositional data are incomplete, i.e. not all components have beendetermined, then it is for the user to es
16、tablish the significance of the errorcaused by their omission and subsequent normalization.NOTE One way to establish the significance of any omission is to determine howcarbon dioxide emission factor changes when the mole fraction of an undeterminedcomponent is estimated to be unity minus the sum of
17、 all raw mole fractions.2 Normative referencesThe following referenced documents are indispensable for the application ofthis document. The latest edition of the referenced document applies.BS EN ISO 6974-1, Natural gas Determination of composition and associateduncertainty by gas chromatography Par
18、t 1: General guidelines and calculationof compositionBS EN ISO 6974-2, Natural gas Determination of composition and associateduncertainty by gas chromatography Part 2: Uncertainty calculationsBS EN ISO 6976, Natural Gas Calculation of calorific values, density, relativedensity and Wobbe index from c
19、omposition3 Terms, definitions and unitsFor the purposes of this British Standard, the following terms, definitions andunits apply.3.1 Terms and definitions3.1.1 carbon dioxide emission factormass of carbon dioxide that is produced from complete combustion with oxygenof a specified quantity of gas3.
20、1.2 coverage factornumerical factor used as a multiplier of the combined standard uncertainty inorder to obtain an expanded uncertaintyBRITISH STANDARD BS 8609:2014 The British Standards Institution 2014 1NOTE A coverage factor, k, is typically in the range 2 to 3.3.1.3 gross calorific valueamount o
21、f heat that would be released by the complete combustion withoxygen of a specified quantity of gas, in such a way that the pressure p1atwhich the reaction takes place remains constant, and all the products ofcombustion are returned to the same specified temperature t1as that of thereactants, all of
22、these products being in the gaseous state except for water,which is condensed to the liquid state at t1NOTE Where the quantity of gas is specified on a molar basis, the calorific value isdesignated as (H)G(t1,p1); on a mass basis the calorific value is designated as(Hm)G(t1,p1). Where the quantity o
23、f gas is specified on a volumetric basis, thecalorific value is designated as (Hv)G(t1,p1;t2,p2), where t2and p2are the gas volume(metering) reference conditions.3.1.4 net calorific valueamount of heat that would be released by the complete combustion withoxygen of a specified quantity of gas, in su
24、ch a way that the pressure p1atwhich the reaction takes place remains constant, and all the products ofcombustion are returned to the same specified temperature t1as that of thereactants, all of these products being in the gaseous stateNOTE On molar, mass and volumetric bases, the net calorific valu
25、e is designatedrespectively as (H)N(t1,p1), (Hm)N(t1,p1) and (Hv)N(t1,p1;t2,p2).3.1.5 molar volumevolume occupied by one mole of a real gas at specified conditions of pressureand temperature3.1.6 real gasgas which deviates from volumetric ideality3.2 Symbols and units3.2.1 QuantitiesA number of mole
26、s of carbon atoms in one mole of mixture, mol-1a atomic index for carbon in the generalised componentCaHbNcOdSeB number of moles of hydrogen atoms in one mole of mixture,mol-1b atomic index for hydrogen in the generalised molecular speciesCaHbNcOdSeC carbon dioxide emission factor of the mixture on
27、a molar basis,kgmol-1CGcarbon dioxide emission factor of the mixture on a gross energybasis, kgkJ-1CMcarbon dioxide emission factor of the mixture on a mass basis,kgkg-1CNcarbon dioxide emission factor of the mixture on a net energybasis, kgkJ-1CVcarbon dioxide emission factor of the mixture on a vo
28、lumebasis, kgm-3c atomic index for nitrogen in the generalised componentCaHbNcOdSeBRITISH STANDARDBS 8609:20142 The British Standards Institution 2014d atomic index for oxygen in the generalised componentCaHbNcOdSee atomic index for sulfur in the generalised componentCaHbNcOdSek coverage factorH cal
29、orific value of the mixture on a molar basis, kJmol-1Hm calorific value of the mixture on a mass basis, kJkg-1Hv calorific value of the real gas mixture on a volumetric basis,kJm-3higross calorific value of pure component i on a molar basis,kJmol-1L half standard enthalpy of vaporization of water (=
30、12 vapH),kJmol-1M molar mass of the mixture, kgmol-1mCatomic mass of carbon, kgmol-1mCO2molar mass of carbon dioxide, kgmol-1mHatomic mass of hydrogen, kgmol-1mimolar mass of pure component i, kgmol-1mNatomic mass of nitrogen, kgmol-1mOatomic mass of oxygen, kgmol-1mSatomic mass of sulfur, kgmol-1N
31、number of components in mixturep1combustion pressure, Pap2metering pressure, Paqijelement i,j of molar mass correlation coefficient matrixR gas constant, Jmol-1K-1S mixture Z summation factorsiZ summation factor for pure component it1combustion temperature, Kt2metering temperature, CU expanded uncer
32、tainty = kuu standard uncertainty (1 standard deviation)V molar volume of the mixture = ZRT2P2,m3mol-1ximole fraction of component i in the mixtureY unspecified propertyZ mixture compression factor=1S2ijelement i,j of mole fraction correlation coefficient matrix3.2.2 SubscriptsGgross (calorific valu
33、e) basisi,jcomponent identifiersNnet (calorific value) basisBRITISH STANDARD BS 8609:2014 The British Standards Institution 2014 34 Calculation of the carbon dioxide emission factor4.1 GeneralThe starting point for the calculation of the carbon dioxide emission factor onany of the commonly used base
34、s is the calculation of carbon dioxide emissionfactor on the molar basis, C. The carbon dioxide emission factor on the desiredbasis is accomplished by dividing carbon dioxide emission factor on the molarbasis by the relevant molar property of the gas mixture. The molar property ofthe gas mixture sha
35、ll be calculated according to BS EN ISO 6976.The calculation of carbon dioxide emission factors and their uncertainties, inaccordance with equations 1 to 12, requires values of pure componentproperties that shall be obtained from BS EN ISO 6976.The following terms are used for expressing the subsequ
36、ent equationscompactly:A5oi51i5NxiaiB5oi51i5NxibiM5oi51i5NximiS5oi51i5NxisiH5oi51i5Nxihiwhere mi= aimC+ bimH+ cimN+ dimO+ eimS4.2 Calculation of the carbon dioxide emission factor on themolar basisThe carbon dioxide emission factor on the molar basis shall be calculated from:C5mCO2 A (1)4.3 Calculat
37、ion of the carbon dioxide emission factor on the massbasisThe carbon dioxide emission factor on the mass basis shall be calculated from:CM5mCO2AM (2)4.4 Calculation of the carbon dioxide emission factor on thevolumetric basisThe carbon dioxide emission factor on the volumetric basis shall be calcula
38、tedfrom:CV5mCO2AV (3)BRITISH STANDARDBS 8609:20144 The British Standards Institution 20144.5 Calculation of the carbon dioxide emission factor on thegross combustion energy basisThe carbon dioxide emission factor on the gross combustion energy basis shallbe calculated from:CG5mCO2AH (4)4.6 Calculati
39、on of the carbon dioxide emission factor on the netcombustion energy basisThe carbon dioxide emission factor on the net combustion energy basis shall becalculated from:CN5mCO2AH20849H2LBH20850 (5)5 Uncertainty of calculation5.1 GeneralApplication of the GUM 1 to equations 1 to 5 results inequations
40、8 to 12 below for the standard uncertainty in the carbon dioxideemission factors on each basis.NOTE 1 Depending on the information available, correlation coefficients ijmay ormay not be known.In the absence of more specific information, the correlation coefficients ijshallbe taken to be the elements
41、 of an identity matrix. If uncertainty in the carbondioxide emission factor on a mass basis is required, then the correlationcoefficients qijshall be calculated from:qij5aiaju2(mC) + bibju2(mH) + cicju2(mN) + didju2(mO) + eieju2(mS)uH20849miH20850uH20849mjH20850 (6)whereuH20849miH208505ai2u2(mC) + b
42、i2u2(mH) + ci2u2(mN) + di2u2(mO) + ei2u2(mS)(7)NOTE 2 qijis only used for the calculation of the uncertainty in carbon dioxideemission factor on a mass basis; it is not used for other bases.NOTE 3 For a typical Group H gas, use of the elements of an identity matrix for qijinstead of equation (6) wil
43、l overestimate the uncertainty in carbon dioxide emissionfactor on a mass basis by around 1%.5.2 Calculation of uncertainty in the carbon dioxide emissionfactor on the molar basisThe uncertainty in the carbon dioxide emission factor on the molar basis shall becalculated from:SuH20849CH20850CD2=i51i5
44、Noj51j5NSaiADuH20849xiH20850ijSajADuH20849xjH208501SuH20849mCO2)mCO2D2(8)BRITISH STANDARD BS 8609:2014 The British Standards Institution 2014 55.3 Calculation of uncertainty in the carbon dioxide emissionfactor on the mass basisThe uncertainty in the carbon dioxide emission factor on the mass basis
45、shall becalculated from:SuH20849CMH20850CMD2=i51i5Noj51j5NSaiA2miMDuH20849xiH20850ijSajA2mjMDuH20849xjH20850+i51i5Noj51j5NxiuH20849miH20850MqijxjuH20849mjH20850M 2uH20849mCO2)mCO2i51i5NxiuH20849miH20850miqiCO2+SuH20849mCO2)mCO2D2(9)5.4 Calculation of the uncertainty in the carbon dioxide emissionfac
46、tor on the volumetric basisThe uncertainty in the carbon dioxide emission factor on the volumetric basisshall be calculated from:SuH20849CVH20850CVD2=i51i5Noj51j5NSaiA12SsiZDuH20849xiH20850ijSajA12SsjZDuH20849xjH20850+4S2Z2i51i5Nxi2u2(siH208501SuH20849RH20850RD2+SuH20849mCO2)mCO2D2(10)5.5 Calculatio
47、n of uncertainty in the carbon dioxide emissionfactor on the gross combustion energy basisThe uncertainty in the carbon dioxide emission factor on the gross combustionenergy basis shall be calculated from:SuH20849CGH20850CGD2=i51i5Noj51j5NSaiA2hiHDuH20849xiH20850ijSajA2hjHDuH20849xjH20850+i51i5Nxi2S
48、uH20849hiH20850HD2+SuH20849mCO2)mCO2D2(11)5.6 Calculation of uncertainty in the carbon dioxide emissionfactor on the net combustion energy basisThe uncertainty in the carbon dioxide emission factor on the net combustionenergy basis shall be calculated from:SuH20849CNH20850CND2=i51i5Noj51j5NSaiA2H208
49、49hi2LbiH20850H20849H2LBH20850DuH20849xiH20850ijSajA2H20849hj2LbjH20850H20849H2LBH20850DuH20849xjH20850+i51i5Nxi2SuH20849hiH20850H20849H2LBH20850D2+SBH20849H2LBH20850D2u2(LH208501SuH20849mCO2)mCO2D2(12)5.7 Compositional uncertaintyIn certain circumstances it is appropriate to assume that the uncertainty in thecomponent data and ancillary data is zero. In this case the only source ofuncertainty is from composition and equations 8 to 12 above simplify to just thefirs
