1、 9009276 0022488 925 Dealgnation:D 11 45-80 Wb Standard Method of SAMPLING NATURAL GAS This standard U issued under the rued designation D 1145;the number immediately lollowing the designation indicates the year oloriginil adoption or.in the CIX f revision.the year of lut revision.A number in pareni
2、hesu indicita the year of lut reapproval.1.scope 1.1 This method of sampling covers the pro-cedures for the sampling of natural gas,con-taining different gases as contaminants such as:(f)natural gases containing primarily hydro-carbons and nitrogen,(2)nhural gases con-taining hydrogen sulfide,or org
3、anic sulfur compounds,or other sulfur contaminants,(3)natural gas containing carbon uioxide,(4)nat-ural gas containing gasoline and condensables.These are treated separately and special pre-cautions stated when necessary.The differences in procedures are mainly in degree,rather than in kind.1.2 This
4、 method of sampling is intended to correlate the size or type of sample with the analysis to be run subsequentj on that sample.1.3 The values stated in inch-pound units are to be regarded as the standard.2.Cenerd Considerations 2.1 In collecting samples of natural gas,con-sideration must be given to
5、 the purposes for which the samples are to be used and the conditions under which they must be secured.Consideration must also be given to the volume of sample required for the prirposc intend&,to the size,design,and material af containers;and to the size,length,and material of which the sampling li
6、ne and auxiliary equipment arc con-structed to convey gas from the source of supply into the container and subsequently from the container to the point of use.Account must be taken of the possible constituents in the gas,whether it may contain only hydrocarbons and inert ase3 such as nitrogen and ca
7、rbon dioxide or whether hydrogen sullide,organic mercap tans,or other sulfur contaminants may be pres-ent.The object is to obtain a representative gas sample because any subsequent analysis,re-gardless of the care and accuracy in making any such analytical test,is useless unless a representative sam
8、ple has been obtained.3.Usual Sources of Samples 3.1 Samples of natural gases for test pur-poses may be required from one or more of the following sources:gas wells,field gathering lines,before and ater field processing plant,main transmission trunk pipe line,city distri-bution system,storage holder
9、s,or similar pip-ing,processing.or storage systems.The gas may exist under pressure as high as 9 to 10 o00 psi(62 o00 to 69 o00 kPa),as in some gas wells,or under subatmospheric pressure in others;in transmission lines from 50 to 1200 psi(345 to 8300 kPa);from 3 in.(7.6 cm)of water column pressure t
10、o 100 psi(0.7 to 700 kPa)in city distribution systems.When taking samples under such widely varying conditions special precautions should be observed,to make sure that the particular technique most suitable for the situation is employed.4.Volume of Sample Required 4.1 Volume of sample required depen
11、ds both u p n the analyses to be made and the apparatus to be used.In general,the following minimum volumes of samples,including vol-,Ume needed for purging the apparatus,are recommended.These quantities wili normally suffice for two tests,an original and a check.Thh method L under the juhrdiction o
12、f ASTM Com-mittoc D-3 on Gucous Fue4 and L b e direct mpoaribility oSubcommittec DO3.01 on Colicctioa and Meuuremcnt of G y-2 E n 8p roved Ox.31,1980.P u b U d De-eember 1980.On&y pubiishd u D 1145-50 T.Lui P&OW OdiCiOii D 1 I45-53(195).NOTICE:This standard has either been superseded and replaced by
13、 a new version or discontinued.Contact ASTM International(www.astm.org)for the latest information._-9009276 0022489 8bL For chemical BAS rnilyair lo00 c m a For rclriive cnrity(ipcrific p v i t y)with hilince-type iniinirncnir For heating value dctcrtnini-For hydrogen iulic(Tu-250 to 700 cm iwciler
14、mcihod)For hydropn iulfldc(cid-5 n(0.141 ma)rnlum iulitc method)For mcree rulhir 1.0 nJ(0.28 m)3 io 5 n(0.085 to 0,141 lion ma)IO n (0.2 8 3 m)For poline conicnt For frictionition rnilyiir 5 IO IO na(0.141 to 0.3 m)/teii(severil icitr/diy mir be needed)5 IO IO n(0.141 to 0.2113 ma)10 na(0.3 m)ipprox
15、.For iupcrcxprniihility iciir Simple prcfcrrhly irken direct from iinc o r well into inilyticil ippirriui.IT hydrogen iulfide ir involved the teil ihould k run in ihe field.If o r p i c iulnir only ir involved rrniple niry be irinrported 10 the Iihoriiory,Adsorption o the pidine in charcoal murt k d
16、one in ihc ield.Diriilliiion irum charcoal mpy he done in ihe Iiboritory.5.Descriptions of Terms 5.I Sampling Probe-The sampling probe is that portion of the sampling line attached to and extending into the pipe or velisel containing the gas to be sampled.5.2 Sampling Line-The sampling line is that portion of a flexible or semirigid tubing or piping used for conducting the sample from the sampling probe to the same container.5.3 Sampling Conralncr-The sample con-tainer is the vessel in which th,
