1、Designation: D5515 17aStandard Test Method forDetermination of the Swelling Properties of Bituminous CoalUsing a Dilatometer1This standard is issued under the fixed designation D5515; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、 the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.INTRODUCTIONThe principle of this test method is that the final volume of char obtained at the conclusion of astandar
3、d dilatation test is dependent on the mass of coal in the coal pencil and on the radius of theretort tube. This test method incorporates a procedure which: determines the mass of air-dried coal inthe coal pencil; provides a means to measure the average retort tube radii; and employs a means toreport
4、 coal expansion on an air dried coal mass basis.Other test methods used to determine the swelling properties of bituminous coals include the Ruhr(ISO 8264) and Audibert-Arnu (ISO 349) International Standard Organization (ISO) test methods.However these two ISO test methods provide consistently diffe
5、rent values for percent dilatation andpercent contraction. Percent contraction and dilatation values obtained using the Audibert-Arnu testmethod are higher and lower respectively than those obtained using the Ruhr test method. Thesedifferences have been attributed to trimming the length of the coal
6、pencil from different ends. TheAudibert-Arnu test method specifies that the wider end of the coal pencil be trimmed while the Ruhrtest method specifies that the narrower end of the coal pencil be trimmed.1. Scope1.1 This test method specifies a procedure for the measure-ment of the swelling of bitum
7、inous coal using a dilatometer.1.2 The test method is limited in applicability to those coalswhich have a free swelling index 1 as determined in accor-dance with Test Method D720.1.3 The values stated in SI units (IEEE/ASTM SI-10) are tobe regarded as standard.1.4 This standard does not purport to a
8、ddress 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 of regulatory limitations prior to use.1.5 This international standard was developed in accor
9、-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 ASTM
10、 Standards:2D720 Test Method for Free-Swelling Index of CoalD2013 Practice for Preparing Coal Samples for AnalysisD2234/D2234M Practice for Collection of a Gross Sampleof CoalIEEE/ASTM SI-10 Standard for Use of the InternationalSystem of Units (SI): The Modern Metric System2.2 International Standard
11、ization Organization (ISO) Stan-dards:3ISO 349 Hard Coal-Audibert-Arnu Dilatometer TestISO 8264 Hard CoalDetermination of the Swelling Prop-erties Using a Dilatometer3. Terminology3.1 Abbreviations:3.1.1 basement level reference mark height, BLRMht, thechar height as measured using the BLRM, after r
12、emoving the1This test method is under the jurisdiction of ASTM Committee D05 on Coaland Coke and is the direct responsibility of Subcommittee D05.15 on MetallurgicalProperties of Coal and Coke.Current edition approved Aug. 1, 2017. Published September 2017. Originallyapproved in 1994. Last previous
13、edition approved in 2017 as D5515 17. DOI:10.1520/D5515-17A.2For 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 Summary page onthe ASTM website.3
14、Available from International Organization for Standardization (ISO), 1, ch. dela Voie-Creuse, Case postale 56, CH-1211, Geneva 20, Switzerland, http:/www.iso.ch.This international standard was developed in accordance with internationally recognized principles on standardization established in the De
15、cision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1piston/retort assembly as a unit after completion of the test,expressed in millimetres.3.2 air-dried coal pencil mass, Md
16、ry, the calculated mass ofthe trimmed 60 mm long coal pencil corrected for added water,expressed in grams.3.3 coal pencil, a 60 mm long test specimen formed bycompression in a mold from coal which has been pulverized topass a 250 m (No. 60) sieve.3.4 equivalent percent dilatation for 2.50 g of air d
17、ried coal,%D2.50, the calculated percent expansion for a 2.50 g,unmoistened, 60 mm long, coal pencil corrected for averagetube radii, expressed as a percentage.3.5 maximum contraction temperature, T2, the temperatureat which the coal pencil starts swelling, expressed in degreesCelsius (see Fig. 1a a
18、nd b). For coals which exhibit contractiononly, T2 is the temperature at which the coal pencil initiallyreaches its minimum (see Fig. 1c). For coals that exhibitcontraction only and are still contracting at 500 C, T2 will bereported as taken at 500 C (see Fig. 1d).3.6 maximum dilatation temperature,
19、 T3, the temperature atwhich the coal pencil first reaches a maximum height afterswelling, that does not change by more than 1 %D during thenext 3 C, expressed in degrees Celsius (see Fig. 1a and b). Forcoals that exhibit no dilatation, T3 should be reported ascontraction only (see Fig. 1c and d). F
20、or coals that themaximum dilatation exceeds 300 %, T3 should be reported asthe temperature at which the recorded height reaches 300 %and as taken at 300 %D.3.7 percent contraction, %C, the minimum recorded heightof the char expressed as a positive whole number percentage,based on an initial coal pen
21、cil height of 60 mm (see Fig. 1athrough c). For coals that exhibit expansion followingcontraction, the percent contraction is the last minimumrecorded height. For coals that exhibit contraction only and arestill contracting at 500 C, %C is the height recorded at 500 C(see Fig. 1d).3.8 percent dilata
22、tion, %D, the maximum recorded heightof the char taken at the maximum dilatation temperature, T3,expressed as a whole number percentage, based on an initialcoal pencil height of 60 mm. For coals which the maximumrecorded height is above the initial 60 mm baseline, %D isexpressed as a positive percen
23、tage (see Fig. 1a). For coalswhich the maximum recorded height is below the initial 60 mmbaseline, %D is expressed as negative percentage (see Fig. 1b).For coals that exhibit no dilatation, %D should be reported ascontraction only (see Fig. 1c and d). For percent dilatationmeasurements exceeding 300
24、 %, report %D as greater than ()300 %.3.9 softening temperature, T1, the temperature at which theheight of the coal pencil contracts 1.0 % (0.6 mm) from thehighest recorded initial pencil height, expressed in degreesCelsius (see Fig. 1).3.10 wet coal pencil mass, Mwet, the measured mass of atrimmed
25、60 mm long coal pencil mass, expressed in grams.4. Summary of Test Method4.1 The test involves preparing a coal pencil and determin-ing the changes of the coal pencil height in a retort tube duringa prescribed heating cycle.5. Significance and Use5.1 Values of the dilatation properties of coals may
26、be usedto predict or explain the behavior of a coal or blends duringcarbonization or in other processes such as gasification,liquefaction, and combustion.6. Apparatus6.1 Dilatometer apparatus, a typical arrangement of thedilatometer apparatus is shown in Fig. 2. The apparatusconsists of the followin
27、g:6.1.1 Electric FurnaceThe dilatometer furnace has a coreconsisting of a 65 mm diameter cylindrical block of aluminumbronze, resistant to oxidation, and having a sufficiently highmelting point. The length of the furnace core can vary from400 mm to 460 mm depending on the length of the retort tubesu
28、sed. The block has three symmetrically placed 15 mmdiameter bored holes capable of accepting three retort tubes.The core is heated electrically by insulated resistance windingscapable of being controlled at a temperature ramp rate of 3.0C 6 0.1 C per minute from within 7 min of the time a test issta
29、rted to a final temperature of 520 C. The furnace shallperform in accordance with the specifications outlined in 8.2.The thermocouple used for temperature control is situated in aretort tube placed in the third hole of the core. The thermo-couple tip is placed in contact with the retort tube wall 60
30、 mmabove the bottom of the retort tube plug.6.1.2 System for Measuring Piston Movement andTemperatureThe system shall be capable of measuring theFIG. 1 Types of Dilatation CurvesD5515 17a2linear displacement of the piston to the nearest 1.0 mm andproviding a correlation of displacement with temperat
31、ure.6.1.3 Retort Tube and PistonsThe retort tube consists of aseamless tube of steel, with an internal diameter of 8.00 mm 60.05 mm and an external diameter of 14.50 mm 6 0.05 mm. Itshall have a support collar at the top and be threaded to accepta gas-tight, threaded plug at its base. The retort tub
32、e shall havea minimum length of 345 mm and be supported only by itscollar when placed in the furnace. The retort tube shall bediscarded when its internal diameter exceeds 8.15 mm.6.1.3.1 The piston shall be machined from a steel rod to afinished diameter of 7.80 mm 6 0.05 mm. The piston shall beof s
33、ufficient length to permit the mechanical recording ortransducer assembly to record a coal pencil height of 30 mm.The piston and mechanical recording or transducer assemblyshall weigh 150 g 6 10 g. The piston shall be discarded whenits diameter is less than 7.65 mm.6.1.3.2 The piston and retort tube
34、 shall be marked and usedas a matched set and require identification imprinted on boththe retort tube and its matched piston. A line, called theBasement Level Reference Mark (BLRM), shall be imprintedon the piston, so when assembled with its matched retort tube,with plug in place, the BLRM is even w
35、ith the top of the retorttube. The length from the bottom of the piston to the BLRM isthe length of the retort tube bore with plug in place.6.2 Mold and AccessoriesThe mold and accessories shallbe capable of producing a 60.0 mm 6 0.5 mm long coal pencil.The mold shall have a 70.0 mm 6 0.1 mm inside
36、bore lengthwith a taper of 1:50. The narrow end of the bore shall have adiameter of 6.00 mm 6 0.01 mm. Use a trimming block tofacilitate the trimming of the coal pencil to length and thesubsequent weighing of the trimmed pencil (see Note 1). Theportion of the trimming block holding the pencil shall
37、notweigh more than 155 g.NOTE 1The coal pencil may be trimmed to length from either end.6.3 Cleaning Implements (Recommended)The cleaningimplements for the retort tube consist of an approximately7.95 mm diameter reamer anda9mmbronze wire rifle brushwith suitable attachments to permit cleaning of the
38、 full lengthof the retort tube.Acircular wire brush, attached to a bench topmounted grinder, is recommended for the cleaning of thepistons.6.4 BalanceThe balance shall have a weighing range of160.00 g with 0.01 g readability.7. Preparation of Sample7.1 Collect a gross sample in accordance with the r
39、equire-ments of Test Method D2234/D2234M.7.2 The analysis sample shall consist of a minimum of 50 gof coal pulverized to 250 m (No. 60) sieve in accordance withTest Method D2013. Perform the dilatation analysis on the coalsample passing 250 m (No. 60) sieve within five days afterreduction to 250 m (
40、No. 60) sieve.8. Calibration8.1 For all systems not using a mechanical pen/chart,calibrate the recorder of piston height when there is a differ-ence of 3.0 mm or more between the final char heights ascalculated from the chart readout and those directly measuredusing the BLRM for two consecutive dete
41、rminations.8.2 The furnace, while being ramped at 3 C per minute,must meet the following temperature criteria with the emptyretort tubes placed in Bores 1 and 2 of the furnace and alltemperature measurements made with the thermocouple(s) incontact with the retort tube wall(s): temperatures measured
42、inBores 1 and 2 must be 63.0 C measured at the same height for45 mm intervals encompassing the bottom 180 mm; tempera-tures between the control thermocouple placed in its usualposition and those of Bores 1 and 2 measured at 45 mmintervals shall be 63.0 C for the bottom 135 mm and 66Cfor the next 45
43、mm. The furnace temperature profile shall becalibrated every twelve months.8.3 The dilatometer temperature readout of the measuringthermocouple shall be checked every four months by compari-son with a digital thermometer which is calibrated for the sametype of thermocouple. If the temperature differ
44、ence is greaterthan 3 C, then the dilatometer furnace temperature readoutrequires recalibration using a temperature calibrator.8.4 Calibrate the retort tubes, as described in Annex A1,prior to initial use and after every 50 tests.9. Preparation of the Coal Pencil9.1 All masses shall be recorded to t
45、he nearest 0.01 g. Caremust be taken to avoid sample loss and the following stepsmust be performed without a break.FIG. 2 Typical Dilatometer ApparatusD5515 17a39.1.1 Preparation of Homogeneous Coal Sample and WaterMixThe amount of water in the mix shall be 11 % on a massbasis.9.1.1.1 Weigh a mixing
46、 vessel. Record the mass as M1.9.1.1.2 Add approximately2gofcoal to the pre-weighedmixing vessel; distribute the coal evenly over the bottom of themixing vessel. Record the mass as M2.9.1.1.3 Add approximately 1 mL of distilled water to thecoal. Record the mass as M3.9.1.1.4 Mix the coal and water t
47、ogether using a metalspatula to form a homogeneous paste. Care must be taken toavoid loss of sample.9.1.1.5 Add another increment of approximately8gofcoal.Record the mass as M4. Mix to homogeneity using a metalspatula.9.2 Construction of the Coal Pencil:9.2.1 If a mold release agent has been applied
48、 to the bore ofthe pencil mold, then excess release agent must be removed byforcing a wad of tissue through the bore of the mold beforeadding the moistened coal.9.2.2 Add not less than ten increments of the moistened coalto a mold and compact.9.2.3 Press the coal pencil out of the mold using equipme
49、ntprovided. Gently place the pencil into a trimming block andtrim the pencil to a 60 mm length. Discard the trimmed offportion of the pencil. Record the mass of the trimmed coalpencil and trimming block as M5.9.3 Transfer the trimmed coal pencil into the top of thehorizontally placed retort tube. The coal pencil is gentlypushed to the bottom of the retort tube with the matched piston.Check that the matched piston slides freely inside the retorttube. Record the mass of the trimming block and any fragmentsof the trimmed pencil not transferred into the reto
