ASTM_D_4150_-_08.pdf

Designation:D415008Standard Terminology Relating toGaseous Fuels1This standard is issued under the fixed designation D4150;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 standard defines the terms used in standards thatare the responsiblity of Committee D03 on Gaseous Fuels.These terms are used in:1.1.1 The sampling of gaseous fuels,1.1.2 The analysis of gaseous fuels for composition andvarious other physical properties,and1.1.3 Other practices related to the processing,transmission,and distribution of gaseous fuels.2.Referenced Documents2.1 ISO Standard:ISO NP 14532 Natural GasTerminology23.Terminologyacid gasnatural gas containing high concentrations of hy-drogen sulfide or carbon dioxide,or both,which is acidicwhen in contact with water or water vapor.associated gasnatural gas,also known as gas-cap gas ordome gas,that overlies and is in immediate contact,but notin solution,with crude oil in a reservoir.at-line instrumentinstrument requiring operator interactionto sample gas directly from the pipeline.base conditionstemperature and pressure conditions atwhich natural gas volumes are determined for purposes ofcustody transfer.In natural gas measurement the propertiesof interest are temperature,pressure,and composition.As-suming ideal gas properties,for simplicity,tables of purecompounds can be prepared for use in calculating gasproperties for any composition at“base conditions.”These“base conditions”are chosen near ambient.BtuBritish thermal unit,the amount of energy required toraise the temperature of one pound of water one degreeFahrenheit.One BtuIT(International Table)is equal to1055.056 J.calorimetera device to measure the evolved heat resultingfrom the combustion of a pressed natural gas(CNG)natural gas that is typicallypressurized to 3600 psi.CNG is primarily used as avehicular pressibilitythe property of a material that permits it todecrease in volume when subjected to an increase pressibility factor(z)a factor calculated by taking theratio of the actual volume of a given mass of gas at aspecified temperature and pressure to its volume calculatedfrom the ideal gas law at the same conditions.dew pointthe temperature at any given pressure at whichliquid initially condenses from a gas or vapor.It is specifi-cally applied to the temperature at which water vapor startsto condense from a gas mixture(water dew point),or atwhich hydrocarbons start to condense(hydrocarbon dewpoint).dissolved gasnatural gas held in solution in reservoir liquidsat the prevailing temperature and pressure of the reservoir.dry gasnatural gas containing little or no water vapor.gas qualityquality of gaseous fuel,which is defined by itscomposition and its physical properties.gross heating value(also called higher heating value)theamount of energy per volume transferred as heat from thecomplete,ideal combustion of the gas at standard tempera-ture in which all the water formed by the reaction condensesto liquid.hydratea solid,crystalline material composed of water andcomponents of natural gas formed under pressure at tem-peratures above the freezing point of water.hydrocarbon dew point(see dew point)inert componentsthose elements or components of naturalgas(fuel gas)that do not contribute to the heating value.1This terminology is under the jurisdiction of ASTM Committee D03 onGaseous Fuels and is the direct responsibility of Subcommittee D03.92 onTerminology Classification and Specifications.Current edition approved Dec.1,2008.Published December 2008.Originallyapproved in 1982.Last previous edition approved in 2003 as D4150 03.DOI:10.1520/D4150-08.2Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 in-line instrumentinstrument whose active element is in-stalled in the pipeline and measures at pipeline conditions.interchangeabilitya measure of the degree to which com-bustion characteristics of one gas are comparable to those ofanother gas.Two gases are interchangeable when one gasmay substitute another directly without interfering with theoperation of gas burning appliances or equipment.lean gasnatural gas containing little or no hydrocarbonscommercially recoverable as liquid products.DISCUSSIONWater and recoverable hydrocarbons(ethane andheavier hydrocarbons)are customarily removed from natural gas tomeet contractual or state statutory requirements.liquefied natural gas(LNG)natural gas that has beenliquefied,after processing,for storage or transportationpurposes.(This definition is from ISO NP 14532.)natural gasa naturally occurring mixture of hydrocarbonand nonhydrocarbon gases found in porous geolog