ASTM_D_1826_-_94_2010.pdf

Designation:D182694(Reapproved 2010)Standard Test Method forCalorific(Heating)Value of Gases in Natural Gas Range byContinuous Recording Calorimeter1This standard is issued under the fixed designation D1826;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 parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination with thecontinuous recording calorimeter(Note 1)of the total calorific(heating)value of fuel gas produced or sold in the natural gasrange from 900 to 1200 Btu/standard ft3.NOTE1An extensive investigation of the accuracy of the Cutler-Hammer recording gas calorimeter,when used with gases of high heatingvalue,was made by the National Bureau of Standards in 1957 under aresearch project sponsored by the American Gas Association.1.2 The subjects covered in this test method appear in thefollowing sections:SectionsAir-Gas Ratio Test11Apparatus5Basis of Measurement14Cold Balance Test10Compensation of Complicating Factors13Condition of Gas Sample7Definitions2Installation of Apparatus6MaintenanceAppendix X1Operating PrecautionsAppendix X2Operation and Checking of Apparatus9Precision15Scope1Significance and Use4Standardization of Calorimeter12Standardization,Preliminary,of Calorimeter by Hydrogen8Summary of Test Method31.3 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 appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Terminology2.1 Definitions of Terms Specific to This Standard:2.1.1 The most important terms used in connection with thedetermination of the calorific value of gaseous fuels in record-ing calorimetry are as follows:2.1.2 British Thermal Unit,or Btuis the defined Interna-tional Tables British thermal unit(symbol Btu).NOTE2The defining relationships are:(a)1 Btulb1=2.326 Jg 1(exact)(b)1 lb=453.592 37 g(exact).By these relationships,1 Btu=1 055.055 852 62 J(exact).For mostpurposes,the value rounded to 1 Btu=1 055.056 J is adequate.2.1.3 combustion airair used for combustion,a total of theportion mixed with the gas as primary air and the air suppliedaround the burner tube as secondary air(theoretical air plusexcess air).2.1.4 flue gasesthe products,of combustion remaining inthe gaseous state,together with any excess air.2.1.5 heat-absorbing airthe heat exchange medium usedto absorb the heat of combustion derived from the burning ofgaseous fuel.2.1.6 saturated basisthe expressed total calorific value ofa gas when it is saturated with water vapor at standardtemperature and pressure;1 ft3of this gas is equivalent in drygas content to 0.9826 ft3of dry gas at the standard temperatureof 60F and standard pressure of 14.73 psia.NOTE3The definitions given in 2.1.6 and 2.1.10 are for total calorific(heating)values per standard cubic foot of gas.The definitions corre-sponding to any other unit quantity of gas are obtained by substituting thename of the desired unit in place of the term“standard cubic foot”in thedefinitions.Methods of calculating calorific(heating)values per cubicfoot of gas under any desired conditions of pressure,temperature,andwater vapor content are specified in Section 14.2.1.7 standard cubic foot of gasthe quantity of any gasthat at standard temperature and under standard pressure willfill a space of 1 ft3when in equilibrium with liquid water.2.1.8 standard pressureis 14.73 psia.NOTE4This is the pressure base adopted by the American NationalStandards Institute in 1969(Z132.1).According to Daltons law,this isequivalent to stating that the partial pressure of the gas is:14.73 0.256 36=14.473 64 psiawhere 0.256 36 is the vapor pressure of water in psia at 60F.2.1.9 standard temperature60F,based on the interna-tional practical temperature scale of 1968.2.1.10 total calorific value(gross heating value,higherheating value)of a gas is the number of British thermal unitsevolved by the complete combustion at constant pressure of1This test method is under the jurisdiction ofASTM Committee D03 on GaseousFuels and is the direct responsibility of Subcommittee D03.03 on Determination ofHeating Value and Relative Density of Gaseous Fuels.Current edition approved May 1,2010.Published July 2010.Originally approvedin 1961.Last previous edition approved in 2003 as D1826 94(2003).DOI:10.1520/D1826-94R10.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 one standard cubic foot of gas with air,the temperature of thegas,air,and products of combustion being 60F,and all thewater formed by the combustion reaction being condensed tothe liquid state.3.Summary of Test Method3.1 The heating value is determined by imparting all of theheat obtained