1、Designation: E 955 88 (Reapproved 2004)Standard Test Method forThermal Characteristics of Refuse-Derived FuelMacrosamples1This standard is issued under the fixed designation E 955; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, th
2、e 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 method covers the determination of moisture,noncombustibles and combustibles, and the calculation
3、 ofhigher heating value content of a large mass of refuse-derivedfuel-three (RDF).1.2 This test method may be applicable to any wastematerial, including residues from combustion, from which arepresentative sample can be prepared.1.3 The values stated in SI units are to be regarded as thestandard. Th
4、e values given in parentheses are for informationonly.1.4 This standard does not purport to address all of thesafety concerns, 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
5、of regulatory limitations prior to use. See Section 7 foradditional hazard information.2. Referenced Documents2.1 ASTM Standards:2E711 Test Method for Gross Calorific Value of Refuse-Derived Fuel by the Bomb CalorimeterE 791 Test Method for Calculating Refuse-Derived FuelAnalysis Data from As-Determ
6、ined to Different Bases3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 combustiblesthat portion of the RDF sample whichis consumed upon ignition exclusive of the moisture present inthe sample.3.1.2 macrosamplea representative sample in the order of1 kg mass is used to determin
7、e moisture, combustible, andnoncombustible content without further processing or sizereduction.3.1.3 noncombustiblesthat fraction of a macrosample re-maining after moisture and combustibles are driven off by heatand combustion. It is composed of metallic and glass particlesin addition to the residue
8、 from combustion of organic sub-stances.3.1.4 forms of refuse-derived fuel (RDF): RDF-1Wastes used as a fuel in as-discarded form.RDF-2Wastes processed to coarse particle size with orwithout ferrous metal separation.RDF-3shredded fuel derived from municipal solid waste(MSW) that has been processed t
9、o remove metal, glass, andother inorganics. This material has a particle size such that 95weight % passes through a 2-in. (50 mm) square mesh screen.RDF-4Combustible waste processed into powder form, 95weight % passing 10-mesh screening.RDF-5Combustible waste densified (compressed) into theform of p
10、ellets, slugs, cubettes, or briquettes.RDF-6Combustible waste processed into liquid fuel.RDF-7Combustible waste processed into gaseous fuel.4. Summary of Test Method4.1 A macrosample of RDF is dried and ashed successively.The moisture, combustibles, and noncombustibles content aredetermined gravimet
11、rically.4.2 Heating value of a macrosample of RDF is calculatedusing an established moisture and noncombustible free heatingvalue.4.2.1 Normal practice is for contracting practices to rateRDF on a higher heating value basis.4.2.2 If contracting parties choose to rate RDF on a lowerheating value basi
12、s, provision is made using an establishedmoisture and non-combustible free lower heating value.5. Significance and Use5.1 This test method is available to producers and users ofRDF as a means of determining thermal characteristics of alarge sample of RDF without extensive processing of thelaboratory
13、 sample. It is intended that the results obtained beused to monitor changes in the fuel characteristics of RDF overa period of time.1This test method is under the jurisdiction of ASTM Committee D34 on WasteManagement and is the direct responsibility of Subcommittee D34.03.02 onMunicipal Recovery and
14、 Reuse.Current edition approved March 25, 1988. Published May 1988. Originallypublished as E 955-83. Last previous edition E 955-83.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume inform
15、ation, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6. Apparatus6.1 OvenA large chamber mechanical draft oven (ap-proximately 508 by 508 by 508 mm (20 by 20 by 20 in.
16、) insidedimensions) capable of maintaining a controlled temperaturebetween 100 and 500C may be used. A minimum of one airchange per minute is satisfactory. Air flow should be baffled toprevent any sample loss due to air currents.NOTE 1A home electric oven with self-cleaning mode of operation,modifie
17、d with an air inlet has been found satisfactory.36.2 Balance, having a sensitivity of 0.5 g and a capacity ofat least 2000 g.6.3 Sample ContainerA noncorroding pan (stainless steelor aluminum) approximately 15 dm3(0.5 ft3).NOTE 2Disposable aluminum roasting pans (381 3 508 3 82.6 mm)(12 by 20 by 314
18、) have been suitable for this purpose. (Two pans willprobably be required fora1kgsample).37. Hazards7.1 Due to the origins of RDF in municipal waste, commonsense dictates that some precautions should be observed whenconducting tests on samples. Recommended hygienic practicesinclude use of gloves whe
19、n handling RDF; wearing dust masks(NIOSH approved type); conducting tests under negativepressure hood; and washing hands before eating or smoking.8. Sampling8.1 RDF products are heterogeneous. For this reason, sig-nificant care should be exercised to obtain a representativelaboratory sample from the
20、 RDF lot to be characterized.8.2 The sampling method for this procedure should be basedon agreements between both involved parties.49. Procedure9.1 Moisture Determination:9.1.1 Place a sample of approximately 1 kg into a taredcontainer(s) weighed to the nearest 0.5 g. A maximum depth of10 cm is reco
21、mmended. Quickly weigh the container, andsample to the nearest 0.5 g.9.1.2 Place the container and sample in the oven at 105C(220F) until the sample has attained constant weight. (Con-stant weight is reached when the loss in sample weight is lessthan 0.1 % per hour of the original sample weight).NOT
22、E 3After several runs, a period of time can be established for thematerial to reach constant weight. Overnight drying has been found to beconvenient and sufficient for some RDF products.39.1.3 After a sufficient drying time, remove the samplesfrom the oven and immediately weigh while hot to the near
23、est0.5 g.NOTE 4The practicality of this procedure step is demonstrated inFootnote 3.9.2 Noncombustible Determination:9.2.1 Place the container with the dried sample into alaboratory hood, and ignite the sample with a flame. Stirring isrequired to maintain the flame. Take care so no sample is lostwhe
24、n stirring.NOTE 5Caution: Because of the unknown nature of the material, usecaution during ignition and stirring.9.2.2 When a flame can no longer be maintained, place thecontainer with the partially combusted sample into the oven at500C until constant weight is reached.NOTE 6It may be determined tha
25、t constant weight can be routinelyestablished by allowing samples to ash at the prescribed temperature fora set period of time. (Two hours have been found to be sufficient).NOTE 7A home electric oven in the self cleaning mode modified topermit air circulation has been found to achieve sufficient ash
26、ing during a3 h clean cycle.39.2.3 Remove the container and noncombustibles from theoven. As soon as the container is cool enough to handle, weighto the nearest 0.5 g.10. Calculation10.1 Calculate the percent moisture as follows:A 5B 2 CB3 100 (1)where:A = mass percent moisture,B = “as received” sam
27、ple mass in grams, andC = “dry” sample mass in grams.Round value to nearest percent.10.2 Calculate the percent non-combustibles as follows:D 5EB3 100 (2)where:D = mass percent noncombustibles,E = non-combustibles mass in grams, andB = “as received” sample mass in grams.Round value to nearest percent
28、.10.3 Calculate the percent combustibles as follows:F 5 100 2 A 1 D! (3)where:F = mass percent combustibles,A = mass percent moisture, andD = mass percent non-combustibles.10.4 Calculate the higher heating value as follows:G 5F 3 H100or G 5100 2 A 1 D!#H100(4)where:G = higher heating value “as recei
29、ved,”F = mass percent combustibles,H = higher heating value, moisture and non-combustiblesfree, in MJ/kg (Btu/lb) established by the contractingparties,A = mass percent moisture, andD = mass percent non-combustibles free.NOTE 8Round robin testing sponsored by Committee E-38 on Re-source Recovery has
30、 found that the mean moisture/ash free heating value3Hecklinger, R. S., and Large, R. M., “Determination of the Fuel Characteristicsof Refuse-Derived Fuels by Macroanalysis,” Proceedings of the Seventh MineralWaste Utilization Symposium, U.S. Bureau of Mines, 1980, pp. 8490.4ASTM Subcommittee E38.01
31、 on Energy is currently in the process ofdeveloping procedures for sampling RDF-3.E 955 88 (2004)2on six different samples of RDF analyzed in replicate (4 times) by as manyas twelve different laboratories is 21.92 MJ/kg (9423 Btu/lb) with astandard deviation of 772 kJ/kg (332 Btu/lb).5The relative c
32、onstancy ofRDF higher heating value, moisture and ash free, is corrob-orated by research conducted by the National Bureau of Standards.6Therefore, those using this method may agree to establish a higher heatingvalue, moisture and ash free, of 22 MJ/kg (9400 Btu/lb).As an alternative,those using this
33、 test method may agree to establish or adjust the higherheating value, moisture and ash free, for a particular plant by means ofTest Methods E 711 and E 791.10.5 Optional CalculationCalculate the lower heatingvalue as follows:I 5100 2 A 1 D!#J1002 A 3 10.3! (5)where:I = lower heating value “as recei
34、ved,”A = mass percent moisture,D = mass percent non-combustibles,J = lower heating value moisture and non-combustibles,and free, in MJ/kg (Btu/lb) established by the contact-ing parties.NOTE 9The lower heating value of 20 MJ/kg (8600 Btu/lb) isequivalent to 22 MJ/kg (9400 Btu/lb) higher heating valu
35、e from Note 8.NOTE 10If the analysis is performed on residue from combustion ofmunicipal solid waste, the combustibles in the residue should be largelyfixed carbon. If bomb calorimetry is not available to establish a moistureand ash free heating value, an estimated moisture and ash free heatingvalue
36、 of 28 MJ/kg (12 000 Btu/lb) may be used for residue.11. Report11.1 The report shall include the following RDF Analysis“as received”Moisture A %Combustibles FNoncombustibles DTotal 100 %EitherHigher heating valueMJ/kg (Btu/lb)OrLower heating valueMJ/kg (Btu/lb)12. Precision and Bias12.1 The precisio
37、n and bias of this test method has yet to bedetermined.ASTM 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 of any such patent
38、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 are invited either
39、for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hear
40、ing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard
41、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).5Supporting data (Kieffer, John K., “An Approach for Determining the HeatingValue of Municipal Waste From its Combustible Cont
42、ent”) are available fromASTM Headquarters, 1916 Race St., Philadelphia, PA 19103. Request RR:E-38-1002.6Kirklin, D. R., et al, “The Variability of Municipal Solid Waste and ItsRelationship to the Determination of the Calorific Value of Refuse-Derived Fuels,”Resources and Conservation, Vol 9, 1982, pp. 281300.E 955 88 (2004)3
