ASTM D3466-2006(2018) Standard Test Method for Ignition Temperature of Granular Activated Carbon.pdf

1、Designation: D3466 06 (Reapproved 2018)Standard Test Method forIgnition Temperature of Granular Activated Carbon1This standard is issued under the fixed designation D3466; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of

2、 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 method covers the determination of referenceignition temperature of granular activated carbon in flowingair

3、. This test method provides a basis for comparing theignition characteristics of different carbons, or the change inignition characteristics of the same carbon after a period ofservice.1.2 The ignition temperature, as determined by this testmethod, cannot be interpreted as the probable ignition tem-

4、perature of the same carbon under the operating conditions ofa specific application unless those conditions are essentially thesame as those in this test method.2If it is desired to determinethe ignition temperature of the carbon under a specific set ofoperating conditions, the test may be modified

5、to simulate suchconditions, taking into consideration the following variables:(1) air flow rate; (2) moisture content of the carbon; (3) beddepth; (4) relative humidity of the air stream; (5) heating rate;(6) contaminants (for example, hydrocarbons, etc.) in the airstream; and (7) contaminants that

6、may have been adsorbed bythe carbon under prior service conditions.1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It

7、is theresponsibility of the user of this standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.Specific precautionary statements are given in Section 7.1.5 This international standard was developed in ac

8、cor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 A

9、STM Standards:3D2652 Terminology Relating to Activated CarbonD2854 Test Method for Apparent Density of ActivatedCarbonD3195/D3195M Practice for Rotameter CalibrationE11 Specification for Woven Wire Test Sieve Cloth and TestSievesE220 Test Method for Calibration of Thermocouples ByComparison Techniqu

10、esE300 Practice for Sampling Industrial Chemicals3. Terminology3.1 DefinitionsTerms relating to this test method aredefined in Terminology D2652.4. Summary of Test Method4.1 Asample of carbon is exposed to a heated air stream, thetemperature of which is slowly increased until the carbonignites. The

11、temperature of the carbon bed and of the airentering the bed are recorded, and ignition is defined as thepoint at which the carbon temperature suddenly rises above thetemperature of the air entering the bed.5. Significance and Use5.1 Activated carbons used in gas-phase adsorption may besubjected to

12、heating, either from heat applied externally to thecarbon bed, or heat generated by radioactive4contaminants, orby the adsorption process itself. If the application of heat issudden, or if no ample means to conduct the heat from thecarbon bed exists, the carbon bed may ignite. This test methodprovid

13、es a controlled laboratory test to determine the tempera-tures at which such ignition occurs. As stated in 1.2, this doesnot necessarily give the temperature at which ignition willoccur under a specific bed operating condition. This testmethod does, however, allow some ranking of carbons with1This t

14、est method is under the jurisdiction of ASTM Committee D28 onActivated Carbon and is the direct responsibility of Subcommittee D28.04 on GasPhase Evaluation Tests.Current edition approved June 1, 2018. Published June 2018. Originallyapproved in 1976. Last previous edition approved in 2011 as D4366 0

15、6 (2011).DOI: 10.1520/D3466-06R18.2Suzin, Y., et al., Carbon, Vol 37, 1999, pp. 335346.3For referenced 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 Summar

16、y page onthe ASTM website.4Milham and Kovoch, “Treatment of Airborne Radioactive Wastes,” Interna-tional Atomic Energy Agency, Vienna, 1968 (Paper SM-110/49).Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard w

17、as developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1regard to i

18、gnition temperature, and is a useful quality controlmethod for unused carbons.6. Apparatus6.1 Quartz Ignition Tube and Sample Holder, as shown inFig. 1.6.2 Thermocouples, Chromel-Alumel with Inconel sheath,0.635-mm diameter, three required.6.3 Supply of Clean, Dry, Oil-Free AirThe air must bepassed

19、through a HEPA filter and a bed of activated carboncontaining at least 300 mL of carbon per litre per minute of airflow. Relative humidity of the air must be less than 5 % at25 C.6.4 Flowmeter, capable of metering air flow rates to20 L min.6.5 Heating Mantle, tape, or oven to surround the ignitiontu

20、be; at least 50 W.6.6 Variable Transformer or temperature programmer forheater.6.7 Supply of Compressed Nitrogen.6.8 Quartz Beads, 4 mm in diameter or smaller, as needed toprevent fluidization.6.9 Sieves, (two), 76.2 mm in diameter, 150 m conformingto Specification E11.FIG. 1 Ignition Tube and Sampl

21、e AssemblyD3466 06 (2018)26.10 Potentiometric Recorder or equivalent readout forthermocouples (three or more points).6.11 Programmable Temperature Controller (optional).7. Hazards7.1 The temperature rise in a carbon bed is quite sudden atignition. An adequate supply of nitrogen and an operator mustb

22、e present to quench the fire when this rise occurs. Do not stopnitrogen flow until all thermocouples indicate temperaturessubstantially below ignition.7.2 Combustion products of carbon or carbon impregnantsmay be toxic. It is advisable to conduct this test in a fume hood.8. Sampling8.1 Guidance in s

23、ampling granular activated carbon is givenin Practice E300.9. Preparation of Apparatus9.1 Assemble apparatus as shown in Figs. 1 and 2.9.2 Leak test the assembly and eliminate any leakage.9.3 Obtain a representative sample of carbon of approxi-mately 35 mL in accordance with Practice E300. Blow clea

24、n,dry, oil-free air through the sample, retained between 150-msieves, to remove carbon dust. The flow velocity through thesieves shall be 60 6 20 m/min.9.4 Fill the ignition tube (Fig. 1) to a depth of 25 6 1 mm,using the apparatus and procedure described in Test MethodD2854. Cover the sample with q

25、uartz beads to a depth of atleast 15 mm to prevent fluidization of the carbon bed.10. Calibration10.1 Thermocouples, recorder, and flowmeters require peri-odic calibration by standard laboratory techniques, forexample, Test Method E220 for thermocouples, and PracticeD3195/D3195M for rotometer-type f

26、lowmeters.11. Procedure11.1 Adjust the air flow rate to 14.7 6 0.3 L/min, equivalentto a superificial velocity of 30 6 0.5 m/min.11.2 Adjust the variable transformer or temperature pro-grammer to increase the temperature of the air stream reachingthe sample at a rate of approximately 10 C min (as in

27、dicatedby thermocouple T-1). Continue until air temperature reachesapproximately 150 C, or when the air temperature is approxi-mately 50 C below the anticipated ignition temperature of thesample. At this point, adjust the variable transformer orprogram drive to reduce the air heating rate to approxi

28、mately 2to 3 C min.11.3 Maintain the heating rate of 2 to 3 C min untilignition is achieved, as indicated by a sudden rise in thetemperature measured by thermocouple T-1 or T-2.11.4 On ignition, cut off air flow immediately and introducenitrogen to quench fire.12. Interpretation of Results12.1 Obtai

29、n time-temperature plots, Fig. 3, of the tempera-tures measured by thermocouples T-1 and T-2. Draw tangentsto the heating curves before and after ignition, as shown in Fig.3; ignition temperature is the intersection of the tangents.Repeat for thermocouple T-1. The ignition temperature for thecarbon

30、is defined from the thermocouple that first showsignition.13. Report13.1 Report the following information:13.1.1 Name of the carbon manufacturer,13.1.2 Grade designation and nominal particle size range,13.1.3 Average ignition temperature and whether ignitionoccurred first at the upstream (T-1) or do

31、wnstream (T-2)thermocouple,13.1.4 Temperature of the inlet air at the time of ignition,FIG. 2 Ignition Apparatus SchematicD3466 06 (2018)313.1.5 Name of the agency and technician making the test,and13.1.6 Identification number and date of the test.14. Precision and Bias14.1 The bias of this test met

32、hod is basically the bias of thethermocouple-recorder system. The sensitivity of the ignitionpoint to gas velocity varies from carbon to carbon. Milham andKovach have reported a maximum rate of change of ignitionpoint of 250 C (m s). Thus, the control of flow to60.5 m min (0.0083 m/s) required in 11

33、.1 should introduce nomore than 62 C error in the measurement. Such repeatabilityappears to have been obtained in the above-mentioned studies,when one considers reasonable variations in properties forsuccessive samples of the same carbons; the actual ignitiontemperature spread at a given velocity di

34、d not exceed 65Cinthe vicinity of 500 C.15. Keywords15.1 activated carbonASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity o

35、f any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments a

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38、 of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 3 Determination of Temperature of Carbon at IgnitionD3466 06 (2018)4