1、Designation: E 1358 97 (Reapproved 2006)Standard Test Method forDetermination of Moisture Content of Particulate WoodFuels Using a Microwave Oven1This standard is issued under the fixed designation E 1358; the number immediately following the designation indicates the year oforiginal adoption or, in
2、 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 method provides an alternative method toMethod E 871, for the determinat
3、ion of the moisture ofparticulate wood fuels. Particulate wood fuels are defined inE 1126.1.2 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 practic
4、es and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E 871 Method for Moisture Analysis of Particulate WoodFuelsE 1126 Terminology Relating to Biomass Fuels33. Summary of Test Method3.1 Moisture is determined by establishing the loss i
5、n massof the sample when heated under rigidly controlled conditionsof temperature, time, sample mass, and equipment specifica-tions.44. Significance and Use4.1 This test method provides a rapid determination formoisture in particulate wood fuels in several minutes. Thestandard method, E 871, require
6、s a minimum of 18 h. Thismethod is applicable to situations such as the spot-check of themoisture delivered by truck where a quick indication of themoisture of wood delivered is desirable.5. Apparatus5.1 Microwave OvenAny standard commercial micro-wave oven having a power output of at least 600 W ca
7、n beused.6. Procedure6.1 Obtain a 50 g sample of the wood to be tested usingtechniques outlined in Method E 871.6.2 Determine the weight of 3 sheets of standard papertowels placed on top of each other. Record this mass as MT(Mass of Towels).6.3 Place the 50-g sample of the wood on top of the paperto
8、wels and determine the mass of the initial sample. Record themass as MSTI(Mass of Sample and Towels Initial).6.4 Place the sample in the microwave and heat on fullpower using the schedule shown in Table 1 for the type ofwood fuel being tested. Remove sample and towels from ovenafter each heating int
9、erval, weigh, and stir. When the masschange between successive weighings is less than 0.5 g, recordthis mass as MSTF(Mass of Sample and Towels Final).7. Calculation7.1 Calculate the mass percent moisture in the sample asfollows:Moisture in Sample, %5 MSTI2 MT! 2 MSTF2 MT!/MSTI2 MT!8. Precision and B
10、ias8.1 The following criteria should be used for judging theacceptability of the results:8.1.1 RepeatabilityDuplicate results by the same labora-tory should not be considered suspect unless they differ bymore than 1 %.8.1.2 ReproducibilityThe results submitted by two ormore laboratories should not b
11、e considered suspect unless theydiffer by more than 1.5 %.9. Keywords9.1 microwave oven; moisture content; particulate woodfuels1This test method is under the jurisdiction of ASTM Committee E48 onBiotechnology and is the direct responsibility of Subcommittee E48.05 on BiomassConversion.Current editi
12、on approved Feb. 1, 2006. Published February 2006. Originallyapproved in 1990. Last previous edition approved in 1997 as E1358 - 97.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume inform
13、ation, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.4Harris, Robert A., “Rapid Determination of Wood Fuel Moisture Using aMicrowave Oven for Drying,” Forest Products Journal, Vol 32, No. 10, October1982, pp. 5659.1Copyright ASTM International, 100 Barr Harbor Drive, PO
14、Box C700, West Conshohocken, PA 19428-2959, United States.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 pate
15、nt 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 eith
16、er 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 h
17、earing 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 standa
18、rd 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).TABLE 1 Recommended Heating TimesPine HardwoodChips(AverageMoistureControl 48 %)Sawdust(AverageMoistureControl 46 %)Sawdust
19、 andBark (AverageMoistureControl 42 %)Hogged(AverageMoistureControl 23 %)Hogged(AverageMoistureControl 12 %)4:00 2:00 2:00 1:00 1:00AAAAA1:00 2:00 1:00 1:00 1:000:30 2:00 1:00 1:00 0:30in addition toAA AA0:30 0:30 0:30 in addition toAA Ain addition to in addition to in addition toARemove from oven, weigh, and stir.E 1358 97 (2006)2
