1、Designation: D 5835 95 (Reapproved 2007)Standard Practice forSampling Stationary Source Emissions for the AutomatedDetermination of Gas Concentrations1This standard is issued under the fixed designation D 5835; the number immediately following the designation indicates the year oforiginal adoption o
2、r, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice2covers procedures and equipment thatwill permit, within certain
3、 limits, representative sampling forthe automated determination of gas concentrations of effluentgas streams. The application is limited to the determination ofoxygen (O2), carbon dioxide (CO2), carbon monoxide (CO),sulfur dioxide (SO2), nitric oxide (NO), nitrogen dioxide (NO2)and total oxides of n
4、itrogen (NOx).1.2 Velocity measurements are required to determine themass flow rates of gases. This is not included in this practice.1.3 There are some combustion processes and situations thatmay limit the applicability of this practice. Where suchconditions exist, caution and competent technical ju
5、dgment arerequired, especially when dealing with any of the following:1.3.1 Corrosive or highly reactive components,1.3.2 High vacuum, high pressure, or high temperature gasstreams,1.3.3 Wet flue gases,1.3.4 Fluctuations in velocity, temperature, or concentrationdue to uncontrollable variation in th
6、e process,1.3.5 Gas stratification due to the non-mixing of gasstreams,1.3.6 Measurements made using environmental control de-vices, and1.3.7 Low levels of gas concentrations.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibi
7、lity 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. For more specificsafety precautions, refer to 5.1.4.8, 5.2.1.6, and 6.2.2.1.2. Referenced Documents2.1 ASTM Standards:3D 1356 Terminology R
8、elating to Sampling and Analysis ofAtmospheresD 1608 Test Method for Oxides of Nitrogen in GaseousCombustion Products (Phenol-Disulfonic Acid Proce-dures)D 3154 Test Method for Average Velocity in a Duct (PitotTube Method)2.2 Other Document:40 CFR Part 60, Standards of Performance for StationarySour
9、ces, Appendix A, Test Methods 2, 3, 3a, 6, 6c, 7, 7e,and 1043. Terminology3.1 Definitions:3.1.1 For definitions of terms used in this practice, refer toTerminology D 1356.4. Summary of Practice4.1 This practice describes representative sampling of gasesin a duct, including both extractive and non-ex
10、tractive sam-pling. In extractive sampling, these gases are conditioned toremove aerosols, particulate matter, and other interferingsubstances before being conveyed to the instruments. Innon-extractive sampling, the measurements are made in-situ;therefore, no sample conditioning except filtering is
11、required.4.1.1 Extractive SamplingExtractive sampling includesextraction of the sample, removal of interfering materials, andmaintenance of the gas concentration throughout the samplingsystem for subsequent analysis by appropriate instrumentation(see Fig. 1).1This practice is under the jurisdiction
12、of ASTM Committee D22 on Air Qualityand is the direct responsibility of Subcommittee D22.03 on Ambient Atmospheresand Source Emissions.Current edition approved April 1, 2007. Published June 2007. Originallyapproved in 1995. Last previous edition approved in 2001 as D 5835 - 95(2001).2This practice i
13、s based on ISO 10396, “Stationary source emissionsSamplingfor the automated determination of gas concentrations,” available from InternationalOrganization for Standardization, Casa Postale 56, CH-1211, Geneva, Switzerland.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontac
14、t ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4Available from Supt. of Documents, U.S. Government Printing Office, Wash-ington, DC 20402.1Copyright ASTM International, 100 Barr Harbor D
15、rive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.2 Non-extractive SamplingNon-extractive samplingdoes not involve removal of a sample, and sampling is confinedto the gas stream in the stack or duct (see Figs. 2 and 3).5. Representative Factors5.1 Nature of the Source:5.1.1 The re
16、presentativeness of the determination of gas-eous concentration in enclosed gas streams depends on severalfactors:5.1.1.1 The heterogeneity of the process stream, such asvariations in concentration, temperature, or velocity across theduct caused by moisture or gas stratification,5.1.1.2 Gas leakage
17、or air infiltration and continuous gasreactions, and5.1.1.3 Random errors due to the finite nature of the sampleand the sampling procedure adopted to obtain a representativesample.5.1.2 Representativeness may be difficult to achieve for thefollowing reasons:5.1.2.1 Nature of the source (for example,
18、 cyclic, continu-ous, or batch),5.1.2.2 Concentration level of the gas,5.1.2.3 Size of the source, and5.1.2.4 Configuration of the duct network where samplesare extracted.5.1.3 Where there are difficulties due to the nature of thesource as noted in 5.1.2, establish the concentration profile foreach
19、operating condition and to determine the best samplinglocation.5.1.3.1 Some sources may have more variability in process(for example, cyclic variation) and, consequently, any timedependent measurement may be less representative of theaverage concentration if a full cycle of variability is notsampled
20、.5.1.4 Before any measurements are carried out, it is neces-sary to become familiar with the pertinent operating character-istics of the process from which emissions are to be sampledand determined. These operating characteristics include, butare not necessarily limited to, the following:5.1.4.1 Mod
21、e of process operation (cyclic, batch charging,or continuous),5.1.4.2 Process feed rates and composition,5.1.4.3 Fuel rates and composition,5.1.4.4 Normal operating gas temperatures and pressures,5.1.4.5 Operating and removal efficiency of the pollutioncontrol equipment,5.1.4.6 Configuration of the
22、ducts to be sampled leading togas stratification,5.1.4.7 Volumetric gas flow rates, andNOTEKey:1 Baffle 13 Heater2 In-stack Filter 14 Refrigeration Unit3 Tee 15 Water Discharge4 Probe 16 Vacuum Gage5 Sampling Port 17 Bypass Valve6 Cap 18 Pump7 Pressure Gage 19 Sampling Line (Heating Optional)8 To Ze
23、ro and Span Gases 20 Manifold9 Heat-traced Sampling Line 21 To Analyzer(s)10 Temperature Controller (Line) 22 Rotameter11 Temperature Controller (Box) 23 Vent12 FilterFIG. 1 Extractive Sampling and Conditioning SystemD 5835 95 (2007)25.1.4.8 Expected gas composition and likely interferingsubstances.
24、 (WarningExercise caution if the duct to besampled is under pressure or vacuum, or at a high temperature.)5.2 Location:5.2.1 Inspection ParametersPerform an inspection of thephysical characteristics of the test site to evaluate factors suchas:5.2.1.1 Safety of the personnel,5.2.1.2 Location of the f
25、low disturbances,5.2.1.3 Accessibility of the sampling site,5.2.1.4 Available space for the sampling equipment andinstrumentation and possible scaffolding requirements,5.2.1.5 Availability of suitable electrical power, compressedair, water, steam, etc., and5.2.1.6 Sampling port locations. (WarningUs
26、e the elec-trical equipment in accordance with the local safety require-ments. Where a potentially explosive or hazardous atmosphereis suspected, apply particular attention and precautions toensure the safety of the operations.)5.2.2 Sampling Site Location:5.2.2.1 It is necessary to ensure that the
27、gas concentrationsmeasured are representative of the average conditions insidethe duct or stack. The requirements for the extractive samplingof gas may be not as stringent as those for particulate material.It is important that the sampling location be removed from anyobstructions that will seriously
28、 disturb the gas flow in the ductor stack. The pollutant can have cross sectional variation. Theconcentration at various points of the cross-section shall first bechecked, in order to assess the homogeneity of the flow and todetect any infiltration of air or gas stratification, etc. If apreliminary
29、analysis of cross-section at measurements takenindicates more than 6 15 % variation in concentrations, and ifan alternative acceptable location is not available, multi-pointsampling is recommended.5.2.2.2 Multi-point sampling may be achieved either bymoving the probe from point to point or having a
30、probe withmultiple access ports. Usually, the cross sectional concentra-tion of gaseous pollutants is uniform, because of the diffusionand turbulent mixing. If so, it is only necessary to sample atone point within the stack or duct to determine the averageconcentration. Extract gas samples near the
31、center of the stacksampling site. When using nonextractive systems, obtain aconcentration as representative as possible, but ensure that theinstrument location is representative.5.3 Gas Concentration, Velocity, and Temperature ProfileBefore commencing sampling, determine if there are anyspatial or t
32、emporal fluctuations in the gas concentrations byconducting a preliminary survey of the gas concentration,temperature, and velocity. Measure the concentration, tempera-ture, and velocity at the sampling points several times to obtaintheir spatial and temporal profiles. Conduct this survey whenthe pl
33、ant is operating under conditions that will be representa-tive of normal operation and determine whether the samplingposition is suitable and whether the conditions in the duct aresatisfactory (see 5.1.2).5.3.1 The following test methods may be used to determinegas concentration, temperature, and ve
34、locity:5.3.1.1 O2Test Method D 3154, EPA Test Methods 3 and3a,5.3.1.2 CO2Test Method D 3154, EPA Test Methods 3and 3a,5.3.1.3 COEPA Test Method 10,5.3.1.4 SO2EPA Test Methods 6 and 6c,5.3.1.5 NOxTest Method D 1608, EPA Test Methods 7and 7e,5.3.1.6 Gas TemperatureTest Method D 3154, EPA TestMethod 2,
35、 and5.3.1.7 Gas VelocityTest Method D 3154, EPA TestMethod 2.5.4 Other FactorsThe principle of operation and thecomponents of the instrument systems can significantly affectthe degree to which a collected sample is representative of themeasured gas in the source. For example, a point samplingextract
36、ive system requires more attention to sampling sitelocation than an across-the-stack in-situ sampling system.Furthermore, sampling lines should not be composed ofmaterials that have gas adsorbing properties that can affect theresponse time of the measurement section (see Table A1.1).5.4.1 Exercise c
37、are to preserve the integrity of the sampletaken, by a good selection of equipment, and appropriateheating, drying, and leak testing, etc. In addition, other factorssuch as corrosion, synergies, reaction with components, de-composition, and adsorption might affect the integrity of asample.NOTEKey:1
38、Measurement Cell 6 Data Recorder2 Probe Filter 7 Protective Hood3 Probe 8 Transceiver4 Duct or Stack 9 Probe Mounting5 Gas Calibration LineFIG. 2 Non-Extractive Point MonitorD 5835 95 (2007)36. Equipment6.1 Recommended construction materials are described inAnnex A1.6.2 Components of Extractive Samp
39、ling Equipment:6.2.1 Primary FilterThe filter medium shall be con-structed of an appropriate alloy (such as a specific stainlesssteel cast alloy), quartz borosilicate, ceramics, or anothersuitable material. A filter that retains particles greater than 10m is recommended. A secondary filter might be
40、required aswell (see 6.2.4). The filter medium may be located outside theduct or at the tip of the sample probe (6.2.2). If placed at the tipof the probe, a deflector plate may be added to prevent particlebuild-up on the leading edge of the filter. This will preventblockage of the filter. Avoid cont
41、amination of the filter withparticulate matter where condensate may react with gases,resulting in erroneous result.6.2.2 Probe:6.2.2.1 Metal ProbesThe choice of the metal dependsbasically on the physical and chemical properties of the sampleand on the nature of the gas to be determined. Mild steel i
42、ssubject to corrosion by oxidizing gases and may be porous tohydrogen. Thus, it is preferable to have stainless steel orchromium steels that can be used up to 900C. Other specialsteels or alloys can be used above this temperature. Heat theprobe if condensation occurs in its interior and cool it with
43、 anair or water jacket when sampling in very hot gases. Electri-cally ground metal probes since high voltages are easilygenerated in dry gas streams, causing particulate matter to becollected on the probe surface. Grounding is particularlyimportant when employed in an explosive atmosphere.6.2.2.2 Re
44、fractory Probes (see Annex A1), generally madeof vitreous silica, porcelain, mullite or recrystallized alumina.They are fragile and may warp at high temperatures; with theexception of silica, they may also crack from thermal shock.Borosilicate glass probes can withstand temperatures up to500C and vi
45、treous silica probes up to 1000C. Some refractorsof advanced ceramic materials can withstand temperatureshigher than 1000C.6.2.3 Heated Sampling Line Connected to Moisture Re-moval Assembly:6.2.3.1 The sampling line shall be made of stainless steel, orPolytetrafluoroethylene (PTFE).6.2.3.2 The tube
46、diameter shall be adequate to provide aflow rate that is sufficient to feed the monitors, bearing in mindthe sampling line length and the pressure characteristics of thesampling pump (6.2.5) used.6.2.3.3 Maintain the sampling line at a temperature of atleast 15C above the water and acid dew-point te
47、mperature ofthe sampled gas. Monitor the temperature.6.2.3.4 In order to reduce the residence time in the samplingline and the risk of physico-chemical transformation of thesample, the gas flow can be greater than that required for theNOTEKey:1 Lamp 7 Electronic Module2 Transmitter Assembly 8 Data R
48、ecorder3 Internal Gas Calibration Cell 9 Stack or Duct4 Receiver Assembly 10 Alignment/Calibration Pipe5 Protective Windows 11 Purge Air Blower6 Detector 12 Gas Calibration LineFIG. 3 Non-Extractive Path MonitorD 5835 95 (2007)4analytical units; only part of the sample is then analyzed andthe excess
49、 flow discarded through a bypass valve (see Fig. 1).It may be necessary to heat the transport line to avoidcondensation.6.2.4 Secondary Filter:6.2.4.1 A secondary filter may be needed to remove theremaining particulate material, in order to protect the pump(6.2.5) and analyzer. It shall follow the sampling line (6.2.3)immediately downstream of the probe. A filter that retainsparticles greater than 1 m is recommended. Acceptablematerials are PTFE or quartz borosilicate. The size of the filtershall be determined from the required sample flow and themanufact
