1、Designation: D6331 98 (Reapproved 2005)D6331 13Standard Test Method forDetermination of Mass Concentration of Particulate Matterfrom Stationary Sources at Low Concentrations (ManualGravimetric Method)1This standard is issued under the fixed designation D6331; the number immediately following the des
2、ignation 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 method2 covers a me
3、thod for the measurement of particulate matter (dust) concentration in emission gases in theconcentrations below 20 mg/m3 standard conditions, with special emphasis around 5 mg/m3.1.2 To meet the requirements of this test method, the particulate sample is weighed to a specified level of accuracy.At
4、low dustconcentrations, this is achieved by:1.2.1 Exercising extreme care in weighing,1.2.2 Extending the sampling time at conventional sampling rates, or1.2.3 Sampling at higher rates at conventional sampling times (high-volume sampling).1.3 This test method differs from Test Method D3685/D3685M by
5、 requiring the mass measurement of filter blanks, specifyingweighing procedures, and requiring monitoring of the flue gas flow variability over the testing period. It requires that the particulatematter collected on the sample filter have a mass at least five times a positive mass difference on the
6、filter blank. High volumesampling techniques or an extension of the sampling time may be employed to satisfy this requirement.1.4 This test method may be used for calibration of automated monitoring systems (AMS). If the emission gas contains unstable,reactive, or semi-volatile substances, the measu
7、rement will depend on the filtration temperature, and in-stack methods may be moreapplicable than out-stack methods for the calibration of automated monitoring systems.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityo
8、f the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D1193 Specification for Reagent WaterD1356 Terminology Relating to Sampling and Analysis of AtmospheresD29
9、86 Practice for Evaluation of Air Assay Media by the Monodisperse DOP (Dioctyl Phthalate) Smoke Test (Withdrawn2004)4D3154 Test Method for Average Velocity in a Duct (Pitot Tube Method)D3631 Test Methods for Measuring Surface Atmospheric PressureD3670 Guide for Determination of Precision and Bias of
10、 Methods of Committee D22D3685/D3685M Test Methods for Sampling and Determination of Particulate Matter in Stack GasesD3796 Practice for Calibration of Type S Pitot TubesE1 Specification for ASTM Liquid-in-Glass ThermometersE2251 Specification for Liquid-in-Glass ASTM Thermometers with Low-Hazard Pr
11、ecision Liquids1 This test method is under the jurisdiction of ASTM Committee D22 on Air Quality and is the direct responsibility of Subcommittee D22.03 on Ambient Atmospheresand Source Emissions.Current edition approved March 1, 2005April 1, 2013. Published May 2005April 2013. Originally approved i
12、n 1998. Last previous edition approved in 19982005 asD6331 - 98.D6331 - 98(2005). DOI: 10.1520/D6331-98R05.10.1520/D6331-13.2 This test method is based on ISO/CD 12141.3, “Stationary Source EmissionsDetermination of Mass Concentration of Particulate Matter (Dust) at LowConcentrationsManual Gravimetr
13、ic Method”, available from International Organization for Standardization, Casa Postale 56, CH-1211, Geneva Switzerland.3 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer
14、to the standards Document Summary page on the ASTM website.4 The last approved version of this historical standard is referenced on www.astm.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the prev
15、ious version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM In
16、ternational, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States12.2 ISO Standards:5ISO 5725 Precision of test methodsDetermination of repeatability and reproducibility by inter-laboratory testsISO 9096 Stationary source emissionsDetermination of concentration and mas
17、s flow rate of particulate material ingas-carrying ducts. Manual gravimetric methodISO 10780 Stationary source emissionsMeasurement of velocity and volume flow rate of gas stream in ducts3. Terminology3.1 For definitions of terms used in this test method, refer to Terminology D1356.3.2 Definitions o
18、f Terms Specific to This Standard:3.2.1 filtration temperaturethe temperature of the sampled gas immediately downstream of the filter.3.2.2 high volume samplingsampling at higher rates than typical in Test Methods D3685/D3685M by using larger diameternozzles and higher flow rates to maintain isokine
19、tic sampling conditions.3.2.2.1 DiscussionNozzle sizes are typically 20 to 50 mm, with corresponding flow rates from 5 to 50 m3/s.3.2.3 hydraulic diameter, dhdh 5 43area of sampling planeperimeter of sampling plane (1)3.2.4 in-stack filtrationfiltration in the stack or duct where the filter in its f
20、ilter housing is placed immediately downstreamof the sampling nozzle and collects particulate matter in the flue gas, under flue gas conditions.3.2.5 measurement seriessuccessive measurements carried out at the same sampling plane and at the same process conditions.3.2.6 out-stack filtrationa sampli
21、ng technique where the filter, in its filter housing, collects particulate matter under controlledtemperature conditions outside of the stack or duct.3.2.7 overall blankthe sample taken in a manner identical to the flue gas test samples, except that the sampling duration isshortened to less than 1 m
22、in.3.2.7.1 DiscussionThe overall blank value is expressed in the same units as the measurement result (for example, mg/m3) using the average samplingvolume of the measurement series. The overall blank includes possible deposits on the filter and surfaces upstream of the filter incontact with the sam
23、ple gas.3.2.8 particulate matter (dust)solid particles of any shape, structure, or density dispersed in the gas phase at flue gastemperature and pressure conditions.3.2.8.1 DiscussionIn accordance with the described test method, all material that may be collected by filtration under specified condit
24、ions and thatremains upstream of the filter and on the filter after drying under specified conditions are considered to be particulate matter.However, for the purposes of some regulatory standards, the definition of particulate matter may extend to condensibles or reactedmaterials collected under sp
25、ecified conditions (for example, specified temperature lower than the flue gas temperature).3.2.9 sampling linethe line in the sampling plane along which the sampling points are located bounded by the inner duct wall.3.2.10 sampling planethe plane normal to the centerline of the duct at the sampling
26、 position.3.2.11 sampling pointthe specific position on a sampling line at which a sample is extracted.3.2.12 weighing control proceduresquality control procedures utilized for detecting/correcting apparent mass variations dueto climatic or environmental changes between pre- and post-sampling weighi
27、ng series.3.2.12.1 DiscussionIn this procedure, control parts, which are identical to those to be weighed for dust measurement and are pretreated under the sameconditions, are used. The control parts are kept free from dust contamination.5 Available from International Organization for Standardizatio
28、n, Casa Postals 56, CH-1211, Geneva, Switzerland.D6331 1324. Summary of Test Method4.1 A sample stream of the gas is extracted for a measured period of time at a controlled flow rate, and the volume of gascollected is subsequently measured. The particulate matter (dust) entrained in the gas sample i
29、s separated by a pre-weighed filter,which is then dried and reweighed. Deposits upstream of the filter in the sampling equipment are also recovered and weighed. Theincrease of mass of the filter and the deposited mass upstream of the filter plus the deposits collected upstream of the filter areattri
30、buted to particulate matter collected from the sampled gas. The ratio of the mass of the particulate matter collected to thevolume of gas collected allows for the calculation of the flue gas particulate concentration.4.2 Valid measurements can be achieved only when:4.2.1 The gas stream in the duct a
31、t the sampling plane has a sufficiently steady and identified velocity, a sufficient temperatureand pressure, and a sufficiently homogeneous composition;4.2.2 The flow of the gas is parallel to the centerline of the duct across the whole sampling plane;4.2.3 Sampling is carried out without disturban
32、ce of the gas stream, using a sharp edged nozzle facing into the stream;4.2.4 Isokinetic sampling conditions are maintained throughout the test;4.2.5 Samples are taken at a preselected number of stated positions in the sampling plane to obtain a representative sample fora non-uniform distribution of
33、 particulate matter in the duct or stack.4.2.6 The sampling train is designed and operated to avoid condensation and to be leak free;4.2.7 Dust deposits upstream of the filter are recovered or taken into account, or both; and4.2.8 The sampling and weighing procedures are adapted to the expected dust
34、 quantities.5. Significance and Use5.1 The measurement of particulate matter and collected residue emission rates is an important test method widely used in thepractice of air pollution control. Particulate matter measurements after control devices are necessary to determine total emissionrates into
35、 the atmosphere.5.1.1 These measurements, when approved by federal or state agencies, are often required for the purpose of determiningcompliance with regulations and statutes.5.1.2 The measurements made before and after control devices are often necessary to demonstrate conformance with contractual
36、performance specifications.5.2 The collected residue obtained with this test method is also important in characterizing stack emissions. However, the utilityof these data is limited unless a chemical analysis of the collected residue is performed.5.3 These measurements also can be used to calibrate
37、continuous particulate emission monitoring systems by correlating theoutput of the monitoring instruments with the data obtained by using this test method.5.3.1 This test method is useful in such correlation applications when emissions are less than 20 mg/m3.5.3.2 The correlation test method is most
38、 valid when the monitoring instrumentation samples the particulate matter under thesame test conditions as this test method.6. Interferences6.1 Gaseous species present in stack gases that are capable of reacting to form particulate matter within the sample train canresult in positive interference.6.
39、1.1 Examples include the potential reaction of sulfur dioxide (SO2) to an insoluble sulfate compound in the moisture portionof the system (such as with limestone in flue gas following a wet flue gas desulfurization system (FGDS) to form calcium sulfate(CaSO4) or the reaction with ammonia gas (NH3) t
40、o form ammonium sulfate (NH4)2 SO4 and the potential reaction of hydrogenfluoride (HF) with glass components in the sample train with resultant collection of silicon tetrafluoride (SiF4) in the impingers.6.2 Volatile matter existing in solid or liquid form in the stack gas may vaporize after collect
41、ion on the sample train filtrationmaterial due to continued exposure to the hot sample stream during the sampling period. Such an occurrence would result in anegative interference. See also Appendix X1.7. Requirements for Sampling Plane and Sampling Points7.1 Representative sampling is possible when
42、 a suitable location that has sufficiently homogeneous gas velocity at the samplingplane is available.7.1.1 Perform sampling at a sufficient number of sampling points, which are usually located on several sampling lines.Convenient access ports and a working platform are required for the testing. See
43、 Test Method D3685/D3685M for additionalcriteria.7.2 Sampling Plane:7.2.1 The sampling plane shall be situated in a length of straight duct (preferably vertical) with a constant shape and constantcross-sectional area. The sampling shall be conducted as far downstream and upstream from any obstructio
44、n that may cause adisturbance and produce a change in the direction of flow (disturbances can be caused by bends, fans, or control equipment).D6331 1337.2.2 Measurements at all the sampling points defined in 7.3 shall prove that the gas stream at the sampling plane meets thefollowing requirements:7.
45、2.2.1 The angle of gas flow is less than 15 with regard to the duct axis (method for estimation is indicated in Annex C ofISO 10780);7.2.2.2 No local negative flow is present;7.2.2.3 The minimum velocity is measurable by the test method used (for example, using Test Method D3154, a differentialpress
46、ure larger than 5 Pa); and7.2.2.4 The ratio of the highest to lowest local gas velocities is less than 3:1.7.2.3 If the above requirements cannot be met, the sampling location will not be in compliance with this test method.7.3 Minimum Number and Location of Sampling Points:7.3.1 See Test Method D31
47、54, Section 8, Figs. 7 and 8, and Tables 1 and 2.7.4 Access Ports:7.4.1 Provide sampling ports for access to the sampling points selected, in accordance with 7.3 and Test Method D3154.7.4.2 Ensure that the port dimensions offer ample space for the insertion and removal of the sampling equipment and
48、associateddevices.8. Velocity and Gas Composition Measurement Apparatus8.1 See Section 6, Test Method D3154.9. Sampling Apparatus9.1 Sampling TrainFor schematic drawings of the major sampling train components refer to Fig. 1 for the in-stack methodand Fig. 2 for the out-of-stack method.9.1.1 The mat
49、erials of construction of in-stack and certain out-of-stack components (such as the nozzle, probe, unions, filterholder, gaskets, and other seals) shall be constructed of materials that will withstand corrosive or otherwise reactive componentsor properties of the stack or gas stream, or both. Recommended materials for a normal range of stack and sample conditions includePFTE fluoro hydrocarbons (up to 175C), 316 stainless steel (up to 800C), and some resistant silicone materials (up to 150C).Extreme temperature conditions may require the use of materials s
