ASTM_D_4810_-_20.pdf

Designation:D481020Standard Test Method forHydrogen Sulfide in Natural Gas Using Length-of-StainDetector Tubes1This standard is issued under the fixed designation D4810;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 a procedure for a rapid andsimple field determination of hydrogen sulfide in natural gaspipelines.Available detector tubes provide a total measuringrange of 0.5 ppm by volume up to 40%by volume,althoughthe majority of applications will be on the lower end of thisrange(that is,under 120 ppm).1.2 Typically,sulfur dioxide and mercaptans may causepositive interferences.In some cases,nitrogen dioxide cancause a negative interference.Most detector tubes will have a“precleanse”layer designed to remove certain interferences upto some maximum interferent level.Consult manufacturersinstructions for specific interference information.1.3 UnitsThe values stated in SI units are to be regardedas the standard.1.4 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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D4150 Terminology Relating to Gaseous Fuels2.2 GPA Standard:3No.2377-86 Test for Hydrogen Sulfide and Carbon Dioxidein Natural Gas Using Length of Stain3.Terminology3.1 DefinitionsFor definitions of general terms used inD03 Gaseous Fuels standards,refer to Terminology D4150.4.Summary of Test Method4.1 The sample is drawn through a detector tube filled witha specially prepared chemical.Any hydrogen sulfide present inthe sampling reacts with the chemical to produce a colorchange or stain.The length of the stain produced in the detectortube,when exposed to a measured volume of sample,isdirectly proportional to the amount of hydrogen sulfide presentin the sample.A hand-operated piston or bellows-type pump isused to draw a measured volume of sample through the tube ata controlled rate of flow.The length of stain produced isconverted to ppm(by volume)hydrogen sulfide(H2S),bycomparison to a calibration scale supplied by the manufacturerfor each box of detection tubes(higher range tubes have unitsof percent by volume).The system is direct reading,easilyportable,and completely suited to making rapid spot checks forhydrogen sulfide under field conditions.5.Significance and Use5.1 The measurement of hydrogen sulfide in natural gas isimportant because of gas quality specifications,the corrosivenature of H2S on pipeline materials,and the effects of H2S onutilization equipment.5.2 This test method provides inexpensive field screening ofhydrogen sulfide.The system design is such that it may be usedby nontechnical personnel with a minimum of proper training.6.Apparatus6.1 Length-of-StainDetectorTubeandCalibrationScaleA sealed glass tube with breakoff tips sized to fit thetube holder of the pump.The reagent layer inside the tube,typically a silica gel substrate coated with the active chemicals,1This test method is under the jurisdiction ofASTM Committee D03 on GaseousFuels and is the direct responsibility of Subcommittee D03.07 on Analysis ofChemical Composition of Gaseous Fuels.Current edition approved Dec.15,2020.Published January 2021.Originallyapproved in 1988.Last previous edition approved in 2015 as D4810 06(2015).DOI:10.1520/D4810-20.2For 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 Gas Processors Association(GPA),6060 American Plaza,Suite700,Tulsa,OK 74135,http:/www.gpaglobal.org.Copyright 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 Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.must be specific for hydrogen sulfide and must produce adistinct color change when exposed to a sample of gascontaining hydrogen sulfide.Any substances known to inter-fere must be listed in the instructions a