1、Designation: D5515 97 (Reapproved 2010)Standard 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
2、case of revision, 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 concl
3、usion of astandard 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
4、 a means toreport coal expansion on an air dried coal weight 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
5、 consistently different 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
6、length of the coal 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 th
7、e swelling of bituminous coal using a dilatometer.1.2 The test method is limited in applicability to those coalswhich have a free swelling index $1 as determined inaccordance 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 doe
8、s 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 of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Stan
9、dards: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 Standardizati
10、on 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:basement level reference mark height,BLRMht, the char height as measured using the BLRM, afterremoving the
11、piston/retort assembly as a unit after completionof the test, expressed in millimetres.3.2 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.3.3 dry coal pencil mass,Mdry, the calculated mass of thetrimmed 60-mm-l
12、ong coal pencil corrected for added water,expressed in grams.1This 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 May 1, 2010. Published May 2010.
13、 Originallyapproved in 1994. Last previous edition approved in 2004 as D5515 97 (2004)e2.DOI: 10.1520/D5515-97R10.2For 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 th
14、e standards Document Summary page onthe ASTM website.3Available from International Organization for Standardization (ISO), 1, ch. dela Voie-Creuse, Case postale 56, CH-1211, Geneva 20, Switzerland, http:/www.iso.ch.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken,
15、 PA 19428-2959, United States.3.4 equivalent percent dilatation for 2.50 g of air dried coal,%D2.50, the calculated percent expansion for a 2.50-g, unmoist-ened, 60-mm-long, coal pencil corrected for average tube radii,expressed as a percentage.3.5 maximum contraction temperature, T2, the temperatur
16、eat which the coal pencil starts swelling, expressed in degreesCelsius. For coals which exhibit contraction only, T2 is thetemperature at which the coal pencil reaches its minimum (seeFig. 1). For coals that exhibit contraction only and are stillcontracting at 500C, T2 will be reported as taken at 5
17、00C(see Fig. 1d).3.6 maximum dilatation temperature, T3, the temperature atwhich the coal pencil first reaches a maximum height afterswelling, expressed in degrees Celsius (see Fig. 1).3.7 percent contraction, %C, the minimum recorded heightof char expressed as a percentage, based on an initial coal
18、pencil height of 60 mm (see Fig. 1).3.8 percent dilatation, %D, the maximum recorded heightof char expressed as a percentage, based on an initial coalpencil height of 60 mm (see Fig. 1).3.9 softening temperature, T1, the temperature at which theheight of the coal pencil contracts 1.0 % (0.6 mm) from
19、 thehighest recorded initial pencil height, expressed in degreesCelsius (see Fig. 1).3.10 wet coal pencil mass, Mwet, the measured mass of atrimmed 60-mm-long coal pencil weight, expressed in grams.4. Summary of Test Method4.1 The test involves preparing a coal pencil and determin-ing the changes of
20、 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 be usedto predict or explain the behavior of a coal or blends duringcarbonization or in other processes such as gasification, lique-faction, and combu
21、stion.6. Apparatus6.1 Dilatometer apparatus, a typical arrangement of thedilatometer apparatus is shown in Fig. 2. The apparatusconsists of the following:6.1.1 Electric FurnaceThe dilatometer furnace has a coreconsisting of a 65-mm-diameter cylindrical block of aluminumbronze, resistant to oxidation
22、, and having a sufficiently highmelting point. The length of the furnace core can vary from 400to 460 mm depending on the length of the retort tubes used.The block has three symmetrically placed 15-mm-diameterbored holes capable of accepting three retort tubes. The core isheated electrically by insu
23、lated resistance windings capable ofbeing controlled at a temperature ramp rate of 3.0 6 0.1C perminute from within 7 min of the time a test is started to a finaltemperature of 520C. The furnace shall perform in accordancewith the specifications outlined in 8.2. The thermocouple usedfor temperature
24、control is situated in a retort tube placed in thethird role of the core. The thermocouple tip is placed in contactwith the retort tube wall 60 mm above the bottom of the retorttube plug.6.1.2 System for Measuring Piston Movement andTemperatureThe system shall be capable of measuring theFIG. 1 Types
25、 of Dilatation Curves FIG. 2 Typical Dilatometer ApparatusD5515 97 (2010)2linear displacement of the piston to the nearest 1.0 mm andproviding a correlation of displacement with temperature.6.1.3 Retort Tube and PistonsThe retort tube consists of aseamless tube of steel, with an internal diameter of
26、 8.00 6 0.05mm and an external diameter of 14.50 6 0.05 mm. It shall havea support collar at the top and be threaded to accept a gastight,threaded plug at its base. The retort tube shall have a minimumlength of 345 mm and be supported only by its collar whenplaced in the furnace. The retort tube sha
27、ll be discarded whenits 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 6 0.05 mm. The piston shall be ofsufficient length to permit the mechanical recording or trans-ducer assembly to record a coal pencil height of 30 mm. Thepist
28、on and mechanical recording or transducer assembly shallweigh 150 6 10 g. The piston shall be discarded when itsdiameter is less than 7.65 mm.6.1.3.2 The piston and retort tube shall be marked and usedas a matched set and require identification imprinted on boththe retort tube and its matched piston
29、. 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 with the top of the retorttube. The length from the bottom of the piston to the BLRM isthe length of the retort tube bore wit
30、h plug in place.6.2 Mold and AccessoriesThe mold and accessories shallbe capable of producing a 60.0 6 0.5-mm-long coal pencil.The mold shall have a 70.0 6 0.1-mm inside bore length witha taper of 1:50. The narrow end of the bore shall have adiameter of 6.00 6 0.01 mm. Use a trimming block to facili
31、tatethe trimming of the coal pencil to length and the subsequentweighing of the trimmed pencil (see Note 1). The portion of thetrimming block holding the pencil shall not weigh more than155 g.NOTE 1The coal pencil may be trimmed to length from either end.6.3 Cleaning Implements (Recommended)The clea
32、ningimplements for the retort tube consist of an approximately7.95-mm-diameter reamer and a 9-mm bronze wire rifle brushwith suitable attachments to permit cleaning of the full lengthof the retort tube.Acircular wire brush, attached to a bench topmounted grinder, is recommended for the cleaning of t
33、hepistons.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 require-ments of Test Method D2234/D2234M.7.2 The analysis sample shall consist of a minimum of 50 gof coal pulverized to 250-m (N
34、o. 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 (No. 60) sieve.8. Calibration8.1 For all systems not using a mechanical pen/chart,calibrate the recorder of piston height when the
35、re 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 determinations.8.2 The furnace, while being ramped at 3C per minute,must meet the following temperature criteria with the emptyretort
36、 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 inBores 1 and 2 must be 63.0C measured at the same height for45-mm intervals encompassing the bottom 180 mm; tempera-tures between
37、 the control thermocouple placed in its usualposition and those of Bores 1 and 2 measured at 45-mmintervals shall be 63.0C for the bottom 135 mm and 66C forthe next 45 mm. The furnace temperature profile shall becalibrated every twelve months.8.3 The dilatometer temperature readout of the measuringt
38、hermocouple shall be checked every four months by compari-son with a digital thermometer which is calibrated for the sametype of thermocouple. If the temperature difference is greaterthan 3C, then the dilatometer furnace temperature readoutrequires recalibration using a temperature calibrator.8.4 Ca
39、librate the retort tubes, as described in Annex A1,every four months.9. Preparation of the Coal Pencil9.1 All weights shall be recorded to the nearest 0.01 g. Caremust be taken to avoid sample loss and the following stepsmust be performed without a break.9.1.1 Preparation of Homogeneous Coal Sample
40、and WaterMixThe amount of water in the mix shall be #11 % on aweight basis.9.1.1.1 Weigh a mixing 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 approxi
41、mately 1 mL of distilled water to thecoal. Record the mass as M3.9.1.1.4 Mix the coal and water together 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
42、a metalspatula.9.2 Construction of the Coal Pencil:9.2.1 If a mold release agent has been applied 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
43、the moistened coalto a mold and compact.9.2.3 Press the coal pencil out of the mold using equipmentprovided. 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
44、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 fra
45、gmentsD5515 97 (2010)3of the trimmed pencil not transferred into the retort tube as M6.To determine the accurate mass of coal in the coal pencil, it isessential that any untransferred fragments of the coal pencil areweighed along with the trimming block.10. Procedure10.1 Clean the dilatometer retort
46、 and piston assembly.Firmly attach the retort tube plugs to the retort tubes. Checkthat the matched piston slides freely in the retort tube.10.2 Prepare the coal pencils and load them into the retorttubes as described in Section 9.10.3 Load both retort tube and piston assemblies, chargedwith trimmed
47、 coal pencils, into the dilatometer furnace whichis thermally stabilized at its 315C setpoint. Start the tempera-ture control program immediately after loading is completed.10.4 Attach the mechanism used to measure piston heightand adjust the piston height reading to 0 6 5 %D.10.5 Terminate the test
48、 when no movement of the piston canbe detected for 5 min after completion of the dilatation process.In the instance of no dilatation, terminate the test when thefurnace temperature reaches 500C. Reset the furnace to 315 65C. Remove the piston height-measuring mechanism. Re-move the retort tube and p
49、iston assemblies as a unit. Measureand record the BLRM heights for each piston/retort tubeassembly. Allow the assembly to cool to room temperaturebefore cleaning.10.6 Determine and record the softening (T1), maximumcontraction (T2), maximum dilatation (T3) temperatures, per-cent contraction (%C), and percent dilatation (%D) as definedin Section 3, from the dilatation analysis temperature andheight data.11. Number of Tests11.1 All tests shall be made in duplicate.12. Calculation12.1 Calculate the percent water added to the coal beforepencil making, %H2O, a
