ASTM D1762-1984(2007) Standard Test Method for Chemical Analysis of Wood Charcoal《木炭的化学分析》.pdf

1、Designation: D 1762 84 (Reapproved 2007)Standard Test Method forChemical Analysis of Wood Charcoal1This standard is issued under the fixed designation D 1762; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisio

2、n. 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,volatile matter, and ash in charcoal made from wood. The testmethod is appl

3、icable to lumps and briquets and is designed forthe evaluation of charcoal quality. The test method employsapparatus that is found in most laboratories and is adapted toroutine analyses of a large number of samples.1.2 This standard does not purport to address all of thesafety concerns, if any, asso

4、ciated 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 regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 346 Practice for Collection and Preparation of CokeSamp

5、les for Laboratory AnalysisD 410 Method for Sieve Analysis of Coal3D 3176 Practice for Ultimate Analysis of Coal and CokeD 3180 Practice for Calculating Coal and Coke Analysesfrom As-Determined to Different Bases3. Summary of Method3.1 The sample is ground in a specified manner and themoisture deter

6、mined as loss in weight in a drying oven at105C. Volatile matter is determined as loss in weight at 950Cunder specified conditions. Ash is determined as the residueafter burning to constant weight at 750C.4. Significance and Use4.1 Low quality wood and wood residues are used for woodcharcoal. This t

7、est method is used for evaluating the charcoalto assess the methods of production and assist in developingnew methods.5. Apparatus5.1 Mill,4for grinding samples.5.2 Oven, with automatic temperature control at 105 6 1C.5.3 Muffle Furnace, to control temperatures at 750 6 5Cand 950 6 5C.5.4 Analytical

8、 Balance, with a capacity of at least 100 g anda sensitivity of 0.1 mg.5.5 Containers, airtight, such as screw-top bottles for stor-age of ground samples.5.6 Sieves, as specified in Method D 410.5.7 Crucibles, porcelain, 41 by 37 mm with porcelain lids.5.8 Desiccator, containing calcium chloride as

9、drying agent.6. Sample6.1 Sample SelectionThe sample shall be selected so as tobe representative of all of the material contained in a lot.Sample selection shall be carried out in accordance withPractices D 346, D 3176, and D 3180.6.2 Sample PreparationSamples will normally be air-drycharcoal lumps

10、or briquets. Rainsoaked or wet samples shall bespread out to air-dry before carrying out the analysis. Forpurchase specifications, the moisture content of the charcoal, asreceived, shall be determined on samples ground to pass a No.20 (850-m) sieve, since excessive grinding will result in lossof moi

11、sture due to the generation of heat. For laboratoryevaluation, moisture, ash, and volatile matter shall be deter-mined on a sample ground as follows:6.2.1 All of the selected sample shall be ground; no part ofthe sample shall be rejected. The sample shall be pulverizedrapidly in a mill. Long grindin

12、g times shall be avoided becauseof generated heat which will cause loss of volatile material.Excessive grinding will produce a large amount of fineparticles smaller than a No. 100 (150-m) sieve. These fineparticles contribute to errors of being swept out of the crucibleduring the rapid evolution of

13、gases in the determination ofvolatile matter. Particles that will be retained on a No. 20(850-m) sieve shall not be used. Samples with the followingsieve analysis have been found satisfactory:1This test method is under the jurisdiction of ASTM Committee D07 on Woodand is the direct responsibility of

14、 Subcommittee D07.01 on Fundamental TestMethods and Properties.Current edition approved April 1, 2007. Published April 2007. Originallyapproved in 1960. Last previous edition approved in 2001 as D 1762 84 (2001).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Cus

15、tomer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn4A Wiley Mill, size No. 2, with a 1-mm screen, or an equivalent mill has beenfound satisfactory for this purpose. If you are aware of alter

16、native suppliers, pleaseprovide this information to ASTM International Headquarters. Your comments willreceive careful consideration at a meeting of the responsible technical committee,1which you may attend.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 1942

17、8-2959, United States.Passing Sieve Retained on Sieve Sample, %. No. 20 (850-m) 0No. 20 (850-m) No. 40 (425-m) 14.5No. 40 (425-m) No. 60 (250-m) 18.7No. 60 (250-m) No. 80 (180-m) 7.0No. 80 (180-m) No. 100 (150-m) 3.4No. 100 (150-m) . 56.46.2.2 The ground sample shall be well mixed and stored inan ai

18、rtight container.7. Procedure7.1 Make duplicate determinations.7.2 MoistureHeat the muffle furnace to 750C and placepreviously ignited porcelain crucibles (Note 1) and covers inthe furnace for 10 min. Cool the crucibles in a desiccator for 1h. Weigh the crucibles and add to each approximately 1 g,we

19、ighed to the nearest 0.1 mg, of the ground sample. Place thesamples in the oven at 105C for 2 h. Place the dried samplesin a desiccator for 1 h and weigh (Note 2).NOTE 1In practice, a crucible from a previous determination is used.NOTE 2The sample shall be considered oven-dry when the decreasein wei

20、ght of consecutive weighings is 0.0005 g or less. Succeeding dryingperiods shall be not less than 1 h.7.3 Volatile MatterHeat the muffle furnace to 950C.Preheat the crucibles used for the moisture determination, withlids in place and containing the sample, as follows: with thefurnace door open, for

21、2 min on the outer ledge of the furnace(300C) and then for 3 min on the edge of the furnace (500C)(Note 3). Then move the samples to the rear of the furnace for6 min with the muffle door closed. Watch the samples througha small peep-hole in the muffle door. If sparking occurs, resultswill be in erro

22、r (Note 4). Cool the samples in a desiccator for1 h and weigh.NOTE 3Individual nichrome wire baskets to hold the crucibles areconvenient.NOTE 4If the sparking sample does not check the results of itsnonsparking duplicate within 60.5 %, the analysis shall be repeated.7.4 AshPlace the lids and the unc

23、overed crucible used forthe volatile matter determination, and containing the sample inthe muffle furnace at 750C for 6 h. Cool the crucibles with lidsin place in a desiccator for 1 h and weigh. Repeat burning ofthe sample until a succeeding 1-h period of heating results in aloss of less than 0.0005

24、 g.8. Calculation and Report8.1 Calculate the percentage of moisture in the sample asfollows:Moisture, % 5 A 2 B!/A 3 100 (1)where:A = grams of air-dry sample used, andB = grams of sample after drying at 105C (7.2).8.2 Calculate the percentage of volatile matter in the sampleas follows:Volatile matt

25、er, % 5 B 2 C!/B 3 100 (2)where:C = grams of sample after drying at 950C (7.3).8.3 Calculate the percentage of ash in the sample as follows:Ash, % 5 D/B! 3 100 (3)where:D = grams of residue (7.4).8.4 Report all results to the first decimal place. Values forduplicate determinations should agree withi

26、n the following:Constituent DeterminedPermissible DifferencesBetween Duplicates, %Moisture 0.1Volatile matter 0.5Ash 0.19. Precision and Bias9.1 There is currently no data available with which todevelop a precision and bias statement.10. Keywords10.1 ash; charcoal; moisture; volatile matterASTM Inte

27、rnational 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 rights, and the riskof infringement of such rights, are entirely

28、 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 for revision of this standard or for additional standardsand sho

29、uld 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 hearing you shouldmake your views known to the ASTM Committee on Sta

30、ndards, 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 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).D 1762 84 (2007)2