1、Designation: E 953/E 953M 08Standard Test Method forFusibility of Refuse-Derived Fuel (RDF) Ash1This standard is issued under the fixed designation E 953/E 953M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last revi
2、sion. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the observation of the tempera-tures at which triangular pyramids (cones) prepared from RDFash attain a
3、nd pass through certain stages of fusing and flowwhen heated at a specific rate in controlled, mildly-reducing,and oxidizing atmospheres.1.2 The test method is empirical, and strict observance ofthe requirements and conditions is necessary to obtain repro-ducible temperatures and enable different la
4、boratories to obtainconcordant results.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two sys
5、tems may result in non-conformancewith the standard.1.4 This standard does not purport to address all of thesafety problems, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of
6、 regulatory limitations prior to use. See Section 6 foradditional hazard information.2. Referenced Documents2.1 ASTM Standards:2D 5681 Terminology for Waste and Waste ManagementE 180 Practice for Determining the Precision of ASTMMethods for Analysis and Testing of Industrial and Spe-cialty Chemicals
7、E 829 Practice for Preparing Refuse-Derived Fuel (RDF)Laboratory Samples for Analysis33. Terminology3.1 Definitions and SymbolsThe critical temperaturepoints to be observed are as follows, denoting the atmosphereused:3.2 initial deformation temperature, ITthe temperature atwhich the first rounding o
8、f the apex of the cone occurs.Shrinking or warping of the cone is ignored if the tip remainssharp. In Fig. 1, the first cone shown is an unheated one; thesecond cone, IT, is a typical cone at the initial deformationstage.3.3 softening temperature, STthe temperature at whichthe cone has fused down to
9、 a spherical lump in which theheight is equal to the width at the base as shown by the thirdcone, ST, in Fig. 1.3.4 hemispherical temperature, HTthe temperature atwhich the cone has fused down to a hemispherical lump atwhich point the height is one half the width of the base asshown by the fourth co
10、ne, HT, in Fig. 1.3.5 fluid temperature, FTthe temperature at which thefused mass has spread out in a nearly flat layer with amaximum height of 1.6 mm 116 in. as shown in the fifthcone, FT, in Fig. 1.3.6 For definitions of additional terms used in this testmethod, refer to Terminology D 5681.4. Sign
11、ificance and Use4.1 The standard is available to producers and users of RDFto use in determining the fusibility of ash produced from RDF.4.2 Limitations of Ash Fusibility DataAsh fusibility dataare too often over-interpreted. In practice, types of burningequipment, rate of burning, temperature and t
12、hickness of firebed or ball, distribution of ash forming mineral matter in theRDF, and viscosity of the molten ash may influence ashbehavior more than the ash fusibility characteristics determinedby the laboratory test. Furthermore, conditions existing duringapplied combustion of RDF are so complex
13、that they areimpossible to duplicate completely in a small-scale laboratorytest. Therefore, the test should be considered an empirical oneand the data, at best, only qualitative.1This test method is under the jurisdiction of ASTM Committee D34 on WasteManagement and is the direct responsibility of S
14、ubcommittee D34.03.02 onMunicipal Recovery and Reuse.Current edition approved Sept. 1, 2008. Published November 2008. Originallyapproved in 1983. Last previous edition approved in 2004 as E 953 88 (2004).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Se
15、rvice at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C
16、700, West Conshohocken, PA 19428-2959, United States.5. Apparatus5.1 FurnaceAny gas-fired or electric furnace conformingto the following requirements may be used.5.1.1 The furnace shall be capable of maintaining a uniformtemperature zone in which to heat the ash cones. This zoneshall be such that th
17、e difference in the melting point of 12.7mm 12 in. pieces of pure gold wire when mounted in place ofthe ash cones on the cone support shall be not greater than11C 20F in a reducing atmosphere test run.5.1.2 The furnace shall be capable of maintaining thedesired atmosphere surrounding the cones durin
18、g heating. Thecomposition of the atmosphere, reducing or oxidizing, shall bemaintained within the limits specified in Section 7. The desiredatmosphere in the gas-fired furnace surrounding the cones shallbe obtained by regulation of the ratio of gas to air in thecombustion mixture. The desired atmosp
19、here in the electricfurnace shall be obtained by means of gases introduced into theheating chamber. The muffle shall be gas-impervious, free fromcracks, and the closure-plug tight fitting. Since state-of-the-artfurnaces vary somewhat in design, the gas supply inlet tubeshall be installed per instruc
20、tions of furnace manufacturer.5.1.3 The furnace shall be capable of regulation so that therate of temperature rise shall be 8 6 3C 15 6 5F perminute.5.1.4 The furnace shall provide a means of observing theash cones during the heating. Observation shall be on the samehorizontal plane as the cone-supp
21、ort surface.5.2 Cone MoldA commercially available cone mold asshown in Fig. 2 shall be used. The cone shall be 19 mm 34 in.in height and 6.4 mm 14 in. in width at each side of the basewhich is an equilateral triangle.5.2.1 A steel spatula with a pointed tip, ground off to fit thecone depression in t
22、he mold, is suitable for removal of the ashcone.5.3 Optical Pyrometer or Thermocouple, for temperaturemeasurements, conforming to the following requirements:5.3.1 Optical PyrometerAn optical pyrometer of the dis-appearing filament type shall be used. The instrument shallhave been calibrated to be ac
23、curate within 11C 20F up to1400C 2550F and within 16C 30F from 1400 to 1600C2550F to 2900F (Note 1). The pyrometer filament shall besighted on the cones until the softening point temperature (Fig.1) has been passed, and then sighted on the cone support. Thepyrometer shall have readable graduations n
24、ot larger than5.5C 10F.NOTE 1The pyrometer equipment shall be standardized periodicallyby a suitably equipped standardizing laboratory such as that of theNational Bureau of Standards, or checked periodically against equipmentcertified by the National Bureau of Standards.5.3.2 ThermocoupleA thermocou
25、ple of platinum andplatinum-rhodium, protected from the furnace gases by aglazed porcelain sheath, shall be used with a high-resistancemillivoltmeter or potentiometer accurate and readable to within5.5C 10F. The sheath shall be sealed to the furnace wall byalundum cement. The hot junction of the the
26、rmocouple shalltouch the end of the sheath and shall be located in the center ofthe muffle and immediately to the rear of the cones. Thethermocouple protective sheath shall be checked periodicallyfor cracks. The thermocouple and its meter shall meet therequirements of Section 10. The potentiometer o
27、r millivoltme-ter shall be located or shielded adequately as to prevent radiantor convection heating of the cold junction. The room tempera-ture compensator shall be adjusted to the existing temperature.5.4 Ash-Cone Refractory SupportThe ash cone shall bemounted on a refractory base composed of a mi
28、xture of equalparts by weight of kaolin and alumina conforming to thefollowing requirements:5.4.1 KaolinNF-Grade powder passing a 75-m No.200 sieve.5.4.2 Aluminum OxideReagent grade powder passing a150-m No. 100 sieve.5.5 Refractory Support MoldA mold with flat top andbottom surfaces to provide a re
29、fractory support of suitablethickness to minimize warping shall be used. A side mold notover 6.4 mm 14 in. high of any convenient shape, placed onan iron plate so that the top surface of the refractory mix canbe struck off flat and parallel to the base by means of astraightedge, is satisfactory. For
30、 electric furnace use, legs notFIG. 1 Critical Temperature PointsInch-pound Units,in.SI Units,mm14 6.434 19.1112 38.12 50.23 76.2FIG. 2 Brass Cone MoldE 953/E 953M 082over3mm18 in. long may be provided on the corners of thecone support by suitable holes bored in the iron base plate ofthe mold.5.6 Go
31、ld Wire,4Twenty-four gage or larger round wire of99.98 % purity, but drawn from metal of 99.99 % purity, andhaving a melting point of 1063C 1945F.5.7 Nickel Wire,5Twenty-four gage or larger round wire ofCP nickel 99.98 % pure, fully annealed, and having a meltingpoint of 1452C 2645F.6. Hazards6.1 Du
32、e to the origins of RDF in municipal waste, commonsense dictates that some precautions should be observed whenconducting tests on the samples. Recommended hygenic prac-tices include use of gloves when handling RDF; wearing dustmasks (NIOSH-approved type); especially while milling RDFsamples; conduct
33、ing tests under a negative pressure hood whenpossible; and washing hands before eating or smoking.6.2 Good laboratory practices dictate the precautions thatshould be observed when using compressed gases such ashydrogen or carbon monoxide as reducing gases.7. Test Atmosphere67.1 Gas Fired Furnace:7.1
34、.1 Reducing Atmosphere TestA mildly reducing atmo-sphere surrounding the cones shall be maintained during thetest in the gas-fired furnace. Hydrogen, hydrocarbons, andcarbon monoxide shall be considered as reducing gases;oxygen, carbon dioxide, and water vapor shall be considered asoxidizing gases.
35、Nitrogen is inert. The ratio by volume ofreducing gases to oxidizing gases in the atmosphere shall bebetween the limits of 20 to 80 %, that is, on a nitrogen-freebasis, the total amount of reducing gases present shall bebetween the limits of 20 and 80 volume %. A flame 150 to 200mm 6 to 8 in. in hei
36、ght and tinged with yellow above thefurnace outlet has been found to provide an atmosphere withinthe specified limits.7.1.2 Oxidizing Atmosphere TestAn atmosphere contain-ing a minimum amount of reducing gases shall be maintainedsurrounding the cones during the test in the gas-fired furnace.On a nit
37、rogen-free basis, the volume of the reducing gasespresent in the atmosphere will not exceed 10 volume %.Combustion with the maximum possible quantity of air withpreservation of the specified rate of temperature increase hasbeen found to provide an atmosphere within the specifiedlimits. A completely
38、blue flame, not over 50 mm 2 in. inheight above the outlet at the beginning of the test, provides thedesired atmosphere; and, by regulation of the combustiongas-air ratio, the specified atmosphere and temperature rise canbe maintained.7.2 Electric Furnace:7.2.1 Reducing Atmosphere TestA regulated fl
39、ow of gasof the nominal composition, 60 % carbon monoxide and 40 65 volume % carbon dioxide,7shall be maintained in the heatingchamber throughout the test (Note 2) in the electric furnace.The gas stream shall be regulated by any convenient means toprovide a measured flow of 1.3 to 1.5 furnace volume
40、s perminute.NOTE 2New cylinders of the mixed gas for which a certified analysisis not available should be mixed before use by laying the cylinder on itsside with the protective screw cap in place. The cylinder should then berolled back and forth, 6 to 10 ft in each direction, approximately 15 times.
41、Certified analyses of each cylinder or batch can be obtained for a smallextra charge.7.2.2 Oxidizing Atmosphere TestA regulated stream of airshall be maintained throughout the test in the electric furnace.The gas stream shall be regulated by any convenient means toprovide a measured flow of 1.3 to 1
42、.5 furnace volumes perminute.8. Preparation of Ash8.1 Use RDF milled to passing a 0.5-mm 0.02-in. sieveprepared in accordance with Practice E 829 to obtain the ash byincineration in a well-ventilated muffle furnace. The quantity ofRDF required will vary with the ash content; usually 3 to 5 gof ash w
43、ill suffice for cones for several check determinations.Spread out the analysis sample of RDF in a layer approxi-mately 6.4 mm 14 in. in depth in a fireclay or porcelainroasting dish. Place the dish in the muffle at a low temperature,and gradually heat to redness at such a rate as to avoidmechanical
44、loss from too rapid expulsion of volatile matter.The rate of temperature rise of 500C 932F in 1 h was foundto be satisfactory. Complete the conversion to ash at atemperature of 800 to 900C 1470 to 1650F. Transfer the ashto an agate mortar (Note 3), and grind so it will pass a No. 2000.074 mm sieve.N
45、OTE 3Amechanical agate mortar grinder will save time where manydeterminations are made. An iron mortar or pestle is not recommendedbecause of metallic contamination.8.2 Spread the ash in a thin layer in a fireclay, silica, orporcelain dish and ignite it in a stream of oxygen for 112 hat800 to 850C 1
46、470 to 1560F to ensure complete and uniformoxidation of the ash. Any tube or muffle-type furnace which,when supplied with an oxygen flow of not less than one furnacevolume in 5 min will maintain a highly oxidizing atmosphere,is suitable.NOTE 4It has been found that in most samples, the initial ignit
47、ionoutlined in 8.1 is sufficient to convert the RDF to ash and the reignitionstep in 8.2 is not necessary. Reignition of the ash should be made only ifan observable amount of noncombustible matter or carbon is present.9. Preparation of Cones9.1 Thoroughly mix the ignited ash in a mechanical mixeror
48、on a sheet of glazed paper or oil cloth by raising first onecorner to roll the ash over, and then raising each of the other4Gold wire of this purity can be purchased from the Baker Dental Division ofEngelhard Industries, Inc., 850 Passaic Ave., East Newark, NJ 07029.5Nickel wire of this purity can b
49、e purchased with the additional specifications ofhaving a minimum coefficient of resist for 0 to 100C of 0.00673 Ohm/Ohm C,from the Baker Dental Division of Engelhard Industries, Inc., 850 PassaicAve., EastNewark, NJ 07029.6For information concerning the effect of various atmospheres, see U.S. Bureauof Mines Bulletin 129, 1918.7This gas is available from the Matheson Division of Searle Medical Products,USA, Inc.E 953/E 953M 083corners in rotation in the same manner u
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