1、Designation: D 6331 98 (Reapproved 2005)Standard Test Method forDetermination of Mass Concentration of Particulate Matterfrom Stationary Sources at Low Concentrations (ManualGravimetric Method)1This standard is issued under the fixed designation D 6331; the number immediately following the designati
2、on 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method2covers a method f
3、or the measurementof particulate matter (dust) concentration in emission gases inthe concentrations below 20 mg/m3standard conditions, withspecial emphasis around 5 mg/m3.1.2 To meet the requirements of this test method, theparticulate sample is weighed to a specified level of accuracy.At low dust c
4、oncentrations, this is achieved by:1.2.1 Exercising extreme care in weighing,1.2.2 Extending the sampling time at conventional samplingrates, or1.2.3 Sampling at higher rates at conventional samplingtimes (high-volume sampling).1.3 This test method differs from Test Method D 3685/D 3685M by requirin
5、g the mass measurement of filter blanks,specifying weighing procedures, and requiring monitoring ofthe flue gas flow variability over the testing period. It requiresthat the particulate matter collected on the sample filter have amass at least five times a positive mass difference on the filterblank
6、. High volume sampling techniques or an extension of thesampling time may be employed to satisfy this requirement.1.4 This test method may be used for calibration of auto-mated monitoring systems (AMS). If the emission gas containsunstable, reactive, or semi-volatile substances, the measure-ment wil
7、l depend on the filtration temperature, and in-stackmethods may be more applicable than out-stack methods forthe calibration of automated monitoring systems.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user o
8、f this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D 1193 Specification for Reagent WaterD 1356 Terminology Relating to Sampling and Analysis ofAtmospheresD 2986 Prac
9、tice for Evaluation of Air Assay Media by theMonodisperse DOP (Dioctyl Phthalate) Smoke TestD 3154 Test Method for Average Velocity in a Duct (PitotTube Method)D 3631 Test Methods for Measuring Surface AtmosphericPressureD 3670 Guide for Determination of Precision and Bias ofMethods of Committee D22
10、D 3685/D 3685M Test Methods for Sampling and Determi-nation of Particulate Matter in Stack GasesD 3796 Practice for Calibration of Type S Pitot TubesE1 Specification for ASTM Thermometers2.2 ISO Standards:4ISO 5725 Precision of test methodsDetermination of re-peatability and reproducibility by inter
11、-laboratory testsISO 9096 Stationary source emissionsDetermination ofconcentration and mass flow rate of particulate material ingas-carrying ducts. Manual gravimetric methodISO 10780 Stationary source emissionsMeasurement ofvelocity and volume flow rate of gas stream in ducts3. Terminology3.1 For de
12、finitions of terms used in this test method, refer toTerminology D 1356.3.2 Definitions of Terms Specific to This Standard:1This test method is under the jurisdiction of ASTM Committee D22 on AirQuality and is the direct responsibility of Subcommittee D22.03 on AmbientAtmospheres and Source Emission
13、s.Current edition approved March 1, 2005. Published May 2005. Originallyapproved in 1998. Last previous edition approved in 1998 as D 6331 - 98.2This test method is based on ISO/CD 12141.3, “Stationary Source EmissionsDetermination of Mass Concentration of Particulate Matter (Dust) at LowConcentrati
14、onsManual Gravimetric Method”, available from International Orga-nization for Standardization, Casa Postale 56, CH-1211, Geneva Switzerland.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volum
15、e information, refer to the standards Document Summary page onthe ASTM website.4Available from International Organization for Standardization, Casa Postals 56,CH-1211, Geneva, Switzerland.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United Stat
16、es.3.2.1 filtration temperaturethe temperature of thesampled gas immediately downstream of the filter.3.2.2 high volume samplingsampling at higher rates thantypical in Test Methods D 3685/D 3685M by using largerdiameter nozzles and higher flow rates to maintain isokineticsampling conditions.3.2.2.1
17、DiscussionNozzle sizes are typically 20 to 50mm, with corresponding flow rates from 5 to 50 m3/s.3.2.3 hydraulic diameter, dhdh543 area of sampling planeperimeter of sampling plane(1)3.2.4 in-stack filtrationfiltration in the stack or duct wherethe filter in its filter housing is placed immediately
18、downstreamof the sampling nozzle and collects particulate matter in theflue gas, under flue gas conditions.3.2.5 measurement seriessuccessive measurements car-ried out at the same sampling plane and at the same processconditions.3.2.6 out-stack filtrationa sampling technique where thefilter, in its
19、filter housing, collects particulate matter undercontrolled temperature conditions outside of the stack or duct.3.2.7 overall blankthe sample taken in a manner identicalto the flue gas test samples, except that the sampling durationis shortened to less than 1 min.3.2.7.1 DiscussionThe overall blank
20、value is expressed inthe same units as the measurement result (for example, mg/m3)using the average sampling volume of the measurement series.The overall blank includes possible deposits on the filter andsurfaces upstream of the filter in contact with the sample gas.3.2.8 particulate matter (dust)so
21、lid particles of anyshape, structure, or density dispersed in the gas phase at fluegas temperature and pressure conditions.3.2.8.1 DiscussionIn accordance with the described testmethod, all material that may be collected by filtration underspecified conditions and that remains upstream of the filter
22、 andon the filter after drying under specified conditions are consid-ered to be particulate matter. However, for the purposes ofsome regulatory standards, the definition of particulate mattermay extend to condensibles or reacted materials collectedunder specified conditions (for example, specified t
23、emperaturelower than the flue gas temperature).3.2.9 sampling linethe line in the sampling plane alongwhich the sampling points are located bounded by the innerduct wall.3.2.10 sampling planethe plane normal to the centerlineof the duct at the sampling position.3.2.11 sampling pointthe specific posi
24、tion on a samplingline at which a sample is extracted.3.2.12 weighing control proceduresquality control proce-dures utilized for detecting/correcting apparent mass variationsdue to climatic or environmental changes between pre- andpost-sampling weighing series.3.2.12.1 DiscussionIn this procedure, c
25、ontrol parts, whichare identical to those to be weighed for dust measurement andare pretreated under the same conditions, are used. The controlparts are kept free from dust contamination.4. Summary of Test Method4.1 A sample stream of the gas is extracted for a measuredperiod of time at a controlled
26、 flow rate, and the volume of gascollected is subsequently measured. The particulate matter(dust) entrained in the gas sample is separated by a pre-weighed filter, which is then dried and reweighed. Depositsupstream of the filter in the sampling equipment are alsorecovered and weighed. The increase
27、of mass of the filter andthe deposited mass upstream of the filter plus the depositscollected upstream of the filter are attributed to particulatematter collected from the sampled gas. The ratio of the mass ofthe particulate matter collected to the volume of gas collectedallows for the calculation o
28、f the flue gas particulate concen-tration.4.2 Valid measurements can be achieved only when:4.2.1 The gas stream in the duct at the sampling plane has asufficiently steady and identified velocity, a sufficient tempera-ture and pressure, and a sufficiently homogeneous composi-tion;4.2.2 The flow of th
29、e gas is parallel to the centerline of theduct across the whole sampling plane;4.2.3 Sampling is carried out without disturbance of the gasstream, using a sharp edged nozzle facing into the stream;4.2.4 Isokinetic sampling conditions are maintainedthroughout the test;4.2.5 Samples are taken at a pre
30、selected number of statedpositions in the sampling plane to obtain a representativesample for a non-uniform distribution of particulate matter inthe duct or stack.4.2.6 The sampling train is designed and operated to avoidcondensation and to be leak free;4.2.7 Dust deposits upstream of the filter are
31、 recovered ortaken into account, or both; and4.2.8 The sampling and weighing procedures are adapted tothe expected dust quantities.5. Significance and Use5.1 The measurement of particulate matter and collectedresidue emission rates is an important test method widely usedin the practice of air pollut
32、ion control. Particulate mattermeasurements after control devices are necessary to determinetotal emission rates into the atmosphere.5.1.1 These measurements, when approved by federal orstate agencies, are often required for the purpose of determin-ing compliance with regulations and statutes.5.1.2
33、The measurements made before and after controldevices are often necessary to demonstrate conformance withcontractual performance specifications.5.2 The collected residue obtained with this test method isalso important in characterizing stack emissions. However, theutility of these data is limited un
34、less a chemical analysis of thecollected residue is performed.5.3 These measurements also can be used to calibratecontinuous particulate emission monitoring systems by corre-lating the output of the monitoring instruments with the dataobtained by using this test method.5.3.1 This test method is usef
35、ul in such correlation applica-tions when emissions are less than 20 mg/m3.D 6331 98 (2005)25.3.2 The correlation test method is most valid when themonitoring instrumentation samples the particulate matterunder the same test conditions as this test method.6. Interferences6.1 Gaseous species present
36、in stack gases that are capableof reacting to form particulate matter within the sample traincan result in positive interference.6.1.1 Examples include the potential reaction of sulfurdioxide (SO2) to an insoluble sulfate compound in the moistureportion of the system (such as with limestone in flue
37、gasfollowing a wet flue gas desulfurization system (FGDS) toform calcium sulfate (CaSO4) or the reaction with ammoniagas (NH3) to form ammonium sulfate (NH4)2SO4and thepotential reaction of hydrogen fluoride (HF) with glass com-ponents in the sample train with resultant collection of silicontetraflu
38、oride (SiF4) in the impingers.6.2 Volatile matter existing in solid or liquid form in thestack gas may vaporize after collection on the sample trainfiltration material due to continued exposure to the hot samplestream during the sampling period. Such an occurrence wouldresult in a negative interfere
39、nce. See also Appendix X1.7. Requirements for Sampling Plane and SamplingPoints7.1 Representative sampling is possible when a suitablelocation that has sufficiently homogeneous gas velocity at thesampling plane is available.7.1.1 Perform sampling at a sufficient number of samplingpoints, which are u
40、sually located on several sampling lines.Convenient access ports and a working platform are requiredfor the testing. See Test Method D 3685/D 3685M for addi-tional criteria.7.2 Sampling Plane:7.2.1 The sampling plane shall be situated in a length ofstraight duct (preferably vertical) with a constant
41、 shape andconstant cross-sectional area. The sampling shall be conductedas far downstream and upstream from any obstruction that maycause a disturbance and produce a change in the direction offlow (disturbances can be caused by bends, fans, or controlequipment).7.2.2 Measurements at all the sampling
42、 points defined in 7.3shall prove that the gas stream at the sampling plane meets thefollowing requirements:7.2.2.1 The angle of gas flow is less than 15 with regard tothe duct axis (method for estimation is indicated inAnnex C ofISO 10780);7.2.2.2 No local negative flow is present;7.2.2.3 The minim
43、um velocity is measurable by the testmethod used (for example, using Test Method D 3154,adifferential pressure larger than 5 Pa); and7.2.2.4 The ratio of the highest to lowest local gas velocitiesis less than 3:1.7.2.3 If the above requirements cannot be met, the samplinglocation will not be in comp
44、liance with this test method.7.3 Minimum Number and Location of Sampling Points:7.3.1 See Test Method D 3154, Section 8, Figs. 7 and 8, andTables 1 and 2.7.4 Access Ports:7.4.1 Provide sampling ports for access to the samplingpoints selected, in accordance with 7.3 and Test MethodD 3154.7.4.2 Ensure
45、 that the port dimensions offer ample space forthe insertion and removal of the sampling equipment andassociated devices.8. Velocity and Gas Composition MeasurementApparatus8.1 See Section 6, Test Method D 3154.9. Sampling Apparatus9.1 Sampling TrainFor schematic drawings of the majorsampling train
46、components refer to Fig. 1 for the in-stackmethod and Fig. 2 for the out-of-stack method.9.1.1 The materials of construction of in-stack and certainout-of-stack components (such as the nozzle, probe, unions,filter holder, gaskets, and other seals) shall be constructed ofmaterials that will withstand
47、 corrosive or otherwise reactivecomponents or properties of the stack or gas stream, or both.Recommended materials for a normal range of stack andsample conditions include PFTE fluoro hydrocarbons (up to175C), 316 stainless steel (up to 800C), and some resistantsilicone materials (up to 150C). Extre
48、me temperature condi-tions may require the use of materials such as quartz or anickel-chromium alloy, or a water-cooled probe may be used.9.2 Elements of the Sampling TrainThe sampling train forcollecting particulate matter and collected residue from a gasstream flowing through a stack consists of t
49、he followinginterconnected elements:9.3 NozzlesThe first part of the sampling equipment toencounter the dust or moisture-laden gas stream, or both, is thenozzle. To extract a representative sample of gas and particu-late matter, the nozzle used for sampling shall be within anarrow range of inside diameters.9.3.1 The probe nozzle is provided with a sharp, taperedleading edge and is constructed of either seamless 316 stainlessFIG. 1 In Stack Sampling TrainExample of a Dry Basis Measurement SystemD 6331 98 (2005)3steel tubing or glass formed in a button-hook
