1、Designation: D6060 96 (Reapproved 2009)Standard Practice forSampling of Process Vents with a Portable GasChromatograph1This standard is issued under the fixed designation D6060; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the y
2、ear 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 practice describes a method for direct sampling andanalysis of process vents for volatile organic compound
3、 (VOC)vapors and permanent gases using a portable gas chromato-graph (GC).1.2 This practice is applicable to analysis of permanentgases such as oxygen (O2), carbon dioxide (CO2) and nitrogen(N2), as well as vapors from organic compounds with boilingpoints up to 125C.1.3 The detection limits obtained
4、 will depend on the por-table gas chromatograph and detector used. Detectors availableinclude thermal conductivity, photoionization, argon ioniza-tion, and electron capture. For instruments equipped withthermal conductivity detectors, typical detection limits are oneto two parts per million by volum
5、e (ppm(v) with an applicableconcentration range to high percent by volume levels. Forinstruments with photoionization detectors detection limit ofone to ten parts per billion by volume (ppb(v) are obtainablewith a concentration range from 1000 to 2000 ppm(v). Theargon ionization detector has an achi
6、evable detection limit ofone (ppb(v), while the electron capture detector has anachievable detection limit of one part per trillion by volume(ppt(v) for chlorinated compounds.1.4 The applicability of this practice should be evaluated foreach VOC by determining stability, reproducibility, and linear-
7、ity.1.5 The appropriate concentration range must also be deter-mined for each VOC, as the range will depend on the vaporpressure of the particular VOC.1.6 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
8、 standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Refer to Section 8on Hazards for additional safety precautions.2. Referenced Documents2.1 ASTM Standards:2D1356 Terminology Relating to Sampling and Analysis ofAtm
9、ospheresD3154 Test Method for Average Velocity in a Duct (PitotTube Method)D3464 Test Method for Average Velocity in a Duct Using aThermal AnemometerE355 Practice for Gas Chromatography Terms and Rela-tionships2.2 Other Document:NFPA 496 Standard for Purged and Pressurized Enclosuresfor Electrical E
10、quipment33. Terminology3.1 DefinitionsFor the definition of terms used in thispractice, refer to Terminology D1356 and Practice E355.3.2 Definitions of Terms Specific to This Standard:3.2.1 portablerefers to gas chromatograph with internalbattery, internal sample pump, and internal/rechargeable carr
11、iergas supply cylinder.4. Summary of Practice4.1 One end of a sampling line (typically 6 mm (14 in.)outside diameter TFE-fluorocarbon tubing) is connected to atee in a process vent and the other end to a condensation trap(see 6.1), which is connected to a gas sampling bulb. The outletof the gas samp
12、ling bulb is connected to a sampling pump setat a flow rate of 0.5 to 2 L/min. The sample line from theportable gas chromatograph is inserted through the septum portof the gas sampling bulb.At user selected intervals, the internal1This test method is under the jurisdiction of ASTM Committee D22 on A
13、irQuality and is the direct responsibility of Subcommittee D22.03 on AmbientAtmospheres and Source Emissions.Current edition approved Oct. 1, 2009. Published December 2009. Originallyapproved in 1996. Last previous edition approved in 2001 as D6060 - 96 (2001).DOI: 10.1520/D6060-96R09.2For reference
14、d 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 National Fire Protection Association (NFPA), 1 Batterymarch
15、Park, Quincy, MA 02169-7471, http:/www.nfpa.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.pump of the portable gas chromatograph is activated andprocess vapors drawn through the injection valve of the gaschromatograph and analy
16、zed.5. Significance and Use5.1 This practice has been widely used to obtain massbalance data for process scrubbers, to determine the efficiencyof VOC emission control equipment, and to obtain data tosupport air permit applications.5.2 This practice will have applications to the MACT Ruleand may have
17、 applications to Compliance Assurance Monitor-ing verification required by the 1990 Clean Air Act Title IIIAmendments.5.3 This practice, when used with Test Methods D3464 orD3154 or on-line process flow meter data, can be used tocalculate detailed emission rate profiles for VOCs from processvents.5.
18、4 This practice provides nearly real time results that candetect process changes or upsets that may be missed usingconventional sorbent tube or integrated gas sampling bagsampling.6. Interferences6.1 Water or liquid in the process line will plug the sampleline of the gas chromatograph, since the inj
19、ection valve of mostportable GCs is not heated. The condensation trap is designedto protect the portable gas chromatograph if liquids are presentor occur during process upset.6.2 Interferences sometimes result from analytes havingsimilar retention times during gas chromatography.6.3 General approach
20、es which can be followed to resolvesuch interferences are given below:6.3.1 Change the type of column, length of column, oroperating conditions.6.3.2 Analyze using a nonpolar methyl silicone columnwhich separates according to boiling point of the compoundsand a polar column whose separations are inf
21、luenced by thepolarity of the compounds.46.3.3 Use a mass spectrometer to verify the identity ofpeaks.7. Apparatus7.1 A schematic drawing of a typical sampling setup isshown in Fig. 1. The laptop computer may be physicallylocated near the gas chromatograph as shown in Fig. 1,orlocated remotely. In a
22、ddition, some portable gas chromato-graphs have an integral computer. Use a short piece of 1.5 mm(116 in.) outside diameter by 1 mm (0.04 in.) inside diameterstainless steel tubing as the sampling probe line from the gassampling bulb to the GC inlet.7.2 Portable Gas Chromatograph (GC), with a therma
23、lconductivity, photoionization, argon ionization, electron cap-ture or appropriate detector, internal/rechargeable carrier gassupply, and internal sampling pump.7.2.1 Portable gas chromatographs are typically equippedwith particulate filters which should be replaced periodically.4The columns in most
24、 portable gas chromatographs are easily interchanged. Onemanufacturer has an instrument that simultaneously injects onto two user selectedcolumn modules.FIG. 1 Schematic of Process Sampling EquipmentD6060 96 (2009)27.3 Data Logger, device used for automated storage ofoutput from a flow measurement d
25、evice.7.4 Gas Sampling Bulb, 125 mL capacity with septum port.7.5 Personal Sampling Pump.7.6 Gas-Tight Syringe, 1, 10, 100, 500 mL capacity or otherconvenient sizes for preparing standards.7.7 Microlitre Syringes, 10, 25, 50, 100 L or other conve-nient sizes for preparing standards.7.8 Gas Sampling
26、Bags, for preparation of gas standards.Bags constructed of various polymer films, such as polyvi-nylidene fluoride, fluorinated ethylenepropylene,(tetrafluoroethylene)-fluorocarbon, polyvinylidene chloride,polyethylene and mixed polymer multilayers, with a variety offittings and capacities (typicall
27、y 1 to 200 L) are available.7.9 Thermal Anemometer, Vane Anemometer, Mass Flowme-ter or Pitot Tube, for measurement of vent velocity.7.10 Condensation Trap, Filtering Flask, 250 or 500 mLpolypropylene fitted with a stopper.7.11 TFE-Fluorocarbon Tubing, 6 mm (14 in.) outsidediameter by 5 mm (316 in.)
28、 inside diameter.7.12 Data System, an integral or external computer used forcontrol of operation of a portable gas chromatograph, datareduction, and storage of results.8. Hazards8.1 See NFPA 496 for use of electrical equipment in areasclassified as hazardous by Article 500 of NFPA 70, NationalElectr
29、ical Code. A purged and pressurized enclosure is re-quired.9. Calibration9.1 Suitable knowns may be prepared by the filling of a gassampling bag with a known volume of air. Inject a knownvolume of gas or liquid into the bag and knead the bag to mix.Permeation tubes or rigid chambers may also be used
30、 forpreparation of gas standards. Reference standards in com-pressed gas cylinders certified as to concentration by themanufacturer are also available. Refer to Methods of AirSampling and Analysis5for applicable guidelines for all ofthese gas standard preparation techniques.9.2 Although standards of
31、 some compounds prepared in gasbags are very stable, others show sample loss during storagedue to permeation or surface adsorption.As a general guidelineprepare standards fresh daily.9.3 Prepare at least two reference standards containingvarying concentrations of each component. Bracket the ex-pecte
32、d concentrations of each component in the testing of theprocess vent, if known.9.3.1 Connect the gas sampling bag to the inlet or thecalibration port of the GC and initiate the analysis. Perform atleast triplicate injections of each standard.9.3.2 The quantitative response of a GC detector may bedet
33、ermined by the measurement of the peak height or peak areausing the Data System or electronic integrator.69.3.3 Following the standard analyze a gas sampling bagcontaining air only (blank). If carryover is 1 % increase thesampling period (internal GC pump time). Typical samplingperiods are 20 to 45
34、s, however, this parameter must beoptimized for each VOC analyzed.10. Procedure10.1 Preparation of the Gas Chromatograph:10.1.1 Fill the internal carrier gas reservoir as described bythe manufacturer.10.1.2 Select a carrier gas flow or column pressure andcolumn temperature compatible with the column
35、 selected forthe separation.10.1.3 Calibrate the chromatographic column to determinethe relative retention times and response of the variouscompounds of interest.10.2 Preparation of the Sampling Train:10.2.1 Assemble the sampling train as shown in Fig. 1.Stainless steel or glass may be substituted f
36、or the TFE-fluorocarbon transfer line.710.2.2 For process vents containing high concentrations ofhigher boiling (125C) low vapor pressure (115 %, repeat the analysis of the vent after identifying sourceof the problem. Typical causes of poor recovery include leak insample train, partially or complete
37、ly plugged instrument filter,improper internal pump or injection valve operation, anddetector malfunction.10.3.5 Data reduction, either by peak height or peak areameasurement, may now be performed. Some portable GCsautomatically develop files that can be directly loaded into anEXCEL or Lotus spreads
38、heet format. Most data loggers forrecording of flow also develop files that can be easily loadedinto spreadsheets, which can be combined into one spreadsheetto develop a detailed emission rate profile for each organiccompound. An example of a typical spreadsheet is given inAppendix X1.10.3.6 By dire
39、ct sampling of process vents with a portablegas chromatograph, process trends and conditions can bemonitored and more easily and quickly optimized. A graphicaldisplay illustrating how simultaneous monitoring of the inletand outlet of a water scrubber using two portable gas chro-matographs aided opti
40、mization of flow rate required to removean organic compound from a vent stream is shown inAppendixX2. This chart was created in EXCEL from the data shown inAppendix X1.11. Calculations11.1 Calculation of the Concentration of Organic ChemicalVapor Standards in Gas Sampling Bags:11.1.1 Calculate the c
41、oncentration C in parts per million byvolume (ppm(v) as follows:c 5L 3 D 3 1000 3 24.45MW 3 V(1)where:L = volume of liquid added to bag, L,D = density of liquid, kg/m3,24.45 = molar volume of ideal gas, L/mole, at 25C and101.3 kPa pressure (760 mm Hg),MW = molecular weight of compound, g/mol, andV =
42、 total volume = volume air in bag plus volume ofvaporized liquid added, L, and1000 = 1000 mL/L.11.2 Calculate the vent flow rate at standard conditions.11.2.1 For instruments that correct to standard conditionscalculate as follows:F 5 V 3 A 3 1000 (2)where:F = flow, L/min at 25C and 101.3 kPa pressu
43、re (760 mmHg),V = air velocity, m/min, andA = vent cross sectional area, m2.11.2.2 For instruments that do not automatically correct tostandard conditions:F 5V 3 A 3 P 3 298 3 1000101.3 3 T 1 273!(3)where:P = pressure of vent in kPa, andT = temperature of vent, C.11.3 Calculate the emission rate of
44、organic compound.11.3.1 Calculate ER, the emission rate in kg/h as follows:ER 5C 3 10263 MW 3 F 3 6024.45 3 1000(4)where:C = concentration of compound, ppm(v) (L/L),106= conversion factor for L to L, and1000 = conversion factor for g to kg.12. Keywords12.1 emissions; emission monitoring; gas chromat
45、ography;sampling and analysisAPPENDIXES(Nonmandatory Information)X1. EXCEL SPREADSHEET OF PORTABLE GC RESULTS FOR VOC IN PROCESS VENTX1.1 The data contained in Columns 1 to 3 in Table X1.1were obtained by loading .dif file created by portable GC intoan EXCEL spreadsheet. Column 1 is the date and tim
46、e thesample was analyzed, while Columns 2 and 3 are the concen-trations in ppm(v) of Compound A (CPD-A) found at the inletand outlet of the scrubber vent. The data in Column 4 werecreated by loading data stored by data logger for process ventflow into the EXCEL spreadsheet. The data logger stores av
47、oltage reading which has to be converted to a flow reading.Data contained in the other columns are calculated from data inColumns 2 to 4. Column 5 is Vent Flow (ft/min) = 10 000 3 Voltage Reading of Data Logger. Flow is atstandard conditions of 25C and 101.3 kPa pressure. Column 6is vent flow in met
48、ers/min (m/min) = .30480 3 values in Col-umn 5. Column 7 is flow in standard L/min obtained using EqEq 2. Columns 8 and 9 obtained using Eq Eq 4 convert theconcentrations in ppm(v) at the inlet and outlet of the scrubberto kg/h entering and exiting the water scrubber. Column 10 iswater flow in litre
49、s/min. Column 11 is scrubberefficiency=1(Column 9/Column 8) 3 100.8Method 18Measurement of Gaseous Organic Compound Emissions by GasChromatography, 40 CFR 60, App. A, 1994, pp. 792821.D6060 96 (2009)4FIG. X1.1 EXCEL Spreadsheet of Portable GC Results for VOC in Process VentsD6060 96 (2009)5X2. GRAPH OF KG/H OF VOC INTO AND OUT OF WATER SCRUBBER VERSUS FLOW RATE OF WATER THROUGHSCRUBBERX2.1 The graph (Fig. X1.2) is a plot of Columns 8 and 9(kg/h of Compound A entering and exiting the water scrubber)of Table X1.1 versus the flow rate of water through thesc
