ASTM D5515-97(2010)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:D5515–97 (Reapproved 2010)
Standard Test Method for
Determination of the Swelling Properties of Bituminous Coal
Using a Dilatometer
This standard is issued under the fixed designation D5515; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
The principle of this test method is that the final volume of char obtained at the conclusion of a
standard dilatation test is dependent on the mass of coal in the coal pencil and on the radius of the
retort tube. This test method incorporates a procedure which: determines the mass of air-dried coal in
the coal pencil; provides a means to measure the average retort tube radii; and employs a means to
report 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 consistently different values for percent dilatation and
percent contraction. Percent contraction and dilatation values obtained using the Audibert-Arnu test
method are higher and lower respectively than those obtained using the Ruhr test method. These
differences have been attributed to trimming the length of the coal pencil from different ends. The
Audibert-Arnu test method specifies that the wider end of the coal pencil be trimmed while the Ruhr
test method specifies that the narrower end of the coal pencil be trimmed.
1. Scope D2013 Practice for Preparing Coal Samples for Analysis
D2234/D2234M Practice for Collection of a Gross Sample
1.1 This test method specifies a procedure for the measure-
of Coal
ment of the swelling of bituminous coal using a dilatometer.
IEEE/ASTM SI-10 Standard for Use of the International
1.2 The test method is limited in applicability to those coals
System of Units (SI): The Modern Metric System
which have a free swelling index $1 as determined in
2.2 International Standardization Organization (ISO) Stan-
accordance with Test Method D720.
dards:
1.3 The values stated in SI units (IEEE/ASTM SI-10) are to
ISO 349 Hard Coal-Audibert-Arnu Dilatometer Test
be regarded as standard.
ISO 8264 Hard Coal—Determination of the Swelling Prop-
1.4 This standard does not purport to address all of the
erties Using a Dilatometer
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
3. Terminology
priate safety and health practices and determine the applica-
3.1 Abbreviations:basement level reference mark height,
bility of regulatory limitations prior to use.
BLRM , the char height as measured using the BLRM, after
ht
2. Referenced Documents removing the piston/retort assembly as a unit after completion
2 of the test, expressed in millimetres.
2.1 ASTM Standards:
3.2 coal pencil, a 60-mm-long test specimen formed by
D720 Test Method for Free-Swelling Index of Coal
compression in a mold from coal which has been pulverized to
pass a 250-µm (No. 60) sieve.
This test method is under the jurisdiction of ASTM Committee D05 on Coal
3.3 dry coal pencil mass,M , the calculated mass of the
dry
and Coke and is the direct responsibility of Subcommittee D05.15 on Metallurgical
trimmed 60-mm-long coal pencil corrected for added water,
Properties of Coal and Coke.
expressed in grams.
Current edition approved May 1, 2010. Published May 2010. Originally
e2
approved in 1994. Last previous edition approved in 2004 as D5515 – 97 (2004) .
DOI: 10.1520/D5515-97R10.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Available from International Organization for Standardization (ISO), 1, ch. de
Standards volume information, refer to the standard’s Document Summary page on la Voie-Creuse, Case postale 56, CH-1211, Geneva 20, Switzerland, http://
the ASTM website. www.iso.ch.
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D5515–97 (2010)
3.4 equivalentpercentdilatationfor2.50gofairdriedcoal, 5. Significance and Use
%D ,thecalculatedpercentexpansionfora2.50-g,unmoist-
2.50
5.1 Values of the dilatation properties of coals may be used
ened, 60-mm-long, coal pencil corrected for average tube radii,
to predict or explain the behavior of a coal or blends during
expressed as a percentage.
carbonization or in other processes such as gasification, lique-
3.5 maximum contraction temperature, T2, the temperature
faction, and combustion.
at which the coal pencil starts swelling, expressed in degrees
Celsius. For coals which exhibit contraction only, T2 is the
6. Apparatus
temperature at which the coal pencil reaches its minimum (see
6.1 Dilatometer apparatus, a typical arrangement of the
Fig. 1). For coals that exhibit contraction only and are still
dilatometer apparatus is shown in Fig. 2. The apparatus
contracting at 500°C, T2 will be reported as taken at 500°C
consists of the following:
(see Fig. 1d).
6.1.1 Electric Furnace—The dilatometer furnace has a core
3.6 maximum dilatation temperature, T3, the temperature at
consisting of a 65-mm-diameter cylindrical block of aluminum
which the coal pencil first reaches a maximum height after
bronze, resistant to oxidation, and having a sufficiently high
swelling, expressed in degrees Celsius (see Fig. 1).
meltingpoint.Thelengthofthefurnacecorecanvaryfrom400
3.7 percent contraction, %C, the minimum recorded height
to 460 mm depending on the length of the retort tubes used.
of char expressed as a percentage, based on an initial coal
The block has three symmetrically placed 15-mm-diameter
pencil height of 60 mm (see Fig. 1).
bored holes capable of accepting three retort tubes. The core is
3.8 percent dilatation, %D, the maximum recorded height
heated electrically by insulated resistance windings capable of
of char expressed as a percentage, based on an initial coal
being controlled at a temperature ramp rate of 3.0 6 0.1°C per
pencil height of 60 mm (see Fig. 1).
minute from within 7 min of the time a test is started to a final
3.9 softening temperature, T1, the temperature at which the
temperatureof520°C.Thefurnaceshallperforminaccordance
height of the coal pencil contracts 1.0 % (0.6 mm) from the
with the specifications outlined in 8.2. The thermocouple used
highest recorded initial pencil height, expressed in degrees
for temperature control is situated in a retort tube placed in the
Celsius (see Fig. 1).
third role of the core.The thermocouple tip is placed in contact
3.10 wet coal pencil mass, M , the measured mass of a
wet
with the retort tube wall 60 mm above the bottom of the retort
trimmed 60-mm-long coal pencil weight, expressed in grams.
tube plug.
6.1.2 System for Measuring Piston Movement and
4. Summary of Test Method
Temperature—The system shall be capable of measuring the
4.1 The test involves preparing a coal pencil and determin-
ing the changes of the coal pencil height in a retort tube during
a prescribed heating cycle.
FIG. 1 Types of Dilatation Curves FIG. 2 Typical Dilatometer Apparatus
D5515–97 (2010)
linear displacement of the piston to the nearest 1.0 mm and calculated from the chart readout and those directly measured
providing a correlation of displacement with temperature. using the BLRM for two consecutive determinations.
6.1.3 RetortTubeandPistons—The retort tube consists of a 8.2 The furnace, while being ramped at 3°C per minute,
seamlesstubeofsteel,withaninternaldiameterof8.00 60.05 must meet the following temperature criteria with the empty
mmandanexternaldiameterof14.50 60.05mm.Itshallhave retort tubes placed in Bores 1 and 2 of the furnace and all
a support collar at the top and be threaded to accept a gastight, temperature measurements made with the thermocouple(s) in
threaded plug at its base.The retort tube shall have a minimum contact with the retort tube wall(s): temperatures measured in
length of 345 mm and be supported only by its collar when Bores 1 and 2 must be 63.0°C measured at the same height for
placed in the furnace. The retort tube shall be discarded when 45-mm intervals encompassing the bottom 180 mm; tempera-
its internal diameter exceeds 8.15 mm. tures between the control thermocouple placed in its usual
6.1.3.1 The piston shall be machined from a steel rod to a position and those of Bores 1 and 2 measured at 45-mm
finished diameter of 7.80 6 0.05 mm. The piston shall be of intervalsshallbe 63.0°Cforthebottom135mmand 66°Cfor
sufficient length to permit the mechanical recording or trans- the next 45 mm. The furnace temperature profile shall be
ducer assembly to record a coal pencil height of 30 mm. The calibrated every twelve months.
piston and mechanical recording or transducer assembly shall 8.3 The dilatometer temperature readout of the measuring
weigh 150 6 10 g. The piston shall be discarded when its thermocouple shall be checked every four months by compari-
diameter is less than 7.65 mm. son with a digital thermometer which is calibrated for the same
6.1.3.2 The piston and retort tube shall be marked and used type of thermocouple. If the temperature difference is greater
as a matched set and require identification imprinted on both than 3°C, then the dilatometer furnace temperature readout
the retort tube and its matched piston. A line, called the requires recalibration using a temperature calibrator.
Basement Level Reference Mark (BLRM), shall be imprinted 8.4 Calibrate the retort tubes, as described in Annex A1,
on the piston, so when assembled with its matched retort tube, every four months.
with plug in place, the BLRM is even with the top of the retort
9. Preparation of the Coal Pencil
tube. The length from the bottom of the piston to the BLRM is
9.1 All weights shall be recorded to the nearest 0.01 g. Care
the length of the retort tube bore with plug in place.
must be taken to avoid sample loss and the following steps
6.2 Mold and Accessories—The mold and accessories shall
must be performed without a break.
be capable of producing a 60.0 6 0.5-mm-long coal pencil.
9.1.1 Preparation of Homogeneous Coal Sample and Water
The mold shall have a 70.0 6 0.1-mm inside bore length with
Mix—The amount of water in the mix shall be#11 % on a
a taper of 1:50. The narrow end of the bore shall have a
weight basis.
diameterof6.00 60.01mm.Useatrimmingblocktofacilitate
9.1.1.1 Weigh a mixing vessel. Record the mass as M1.
the trimming of the coal pencil to length and the subsequent
9.1.1.2 Add approximately2gof coal to the pre-weighed
weighingofthetrimmedpencil(seeNote1).Theportionofthe
mixing vessel; distribute the coal evenly over the bottom of the
trimming block holding the pencil shall not weigh more than
mixing vessel. Record the mass as M2.
155 g.
9.1.1.3 Add approximately 1 mL of distilled water to the
NOTE 1—The coal pencil may be trimmed to length from either end.
coal. Record the mass as M3.
6.3 Cleaning Implements (Recommended)—The cleaning
9.1.1.4 Mix the coal and water together using a metal
implements for the retort tube consist of an approximately
spatula to form a homogeneous paste. Care must be taken to
7.95-mm-diameter reamer and a 9-mm bronze wire rifle brush
avoid loss of sample.
with suitable attachments to permit cleaning of the full length
9.1.1.5 Add another increment of approximately8gof coal.
of the retort tube.Acircular wire brush, attached to a bench top
Record the mass as M4. Mix to homogeneity using a metal
mounted grinder, is recommended for the cleaning of the
spatula.
pistons.
9.2 Construction of the Coal Pencil:
6.4 Balance—The balance shall have a weighing range of
9.2.1 If a mold release agent has been applied to the bore of
160.00 g with 0.01-g readability.
the pencil mold, then excess release agent must be removed by
forcing a wad of tissue through the bore of the mold before
7. Preparation of Sample
adding the moistened coal.
7.1 Collect a gross sample in accordance with the require-
9.2.2 Addnotlessthantenincrementsofthemoistenedcoal
ments of Test Method D2234/D2234M. to a mold and compact.
7.2 The analysis sample shall consist of a minimum of 50 g
9.2.3 Press the coal pencil out of the mold using equipment
ofcoalpulverizedto250-µm(No.60)sieveinaccordancewith provided. Gently place the pencil into a trimming block and
TestMethodD2013.Performthedilatationanalysisonthecoal
trim the pencil to a 60-mm length. Discard the trimmed off
sample passing 250-µm (No. 60) sieve within five days after portion of the pencil. Record the mass of the trimmed coal
reduction to 250-µm (No. 60) sieve.
pencil and trimming block as M5.
9.3 Transfer the trimmed coal pencil into the top of the
8. Calibration
horizontally placed retort tube. The coal pencil is gently
8.1 For all systems not using a mechanical pen/chart, pushedtothebottomoftheretorttubewiththematchedpiston.
calibrate the recorder of piston height when there is a differ- Check that the matched piston slides freely inside the retort
ence of 3.0 mm or more between the final char heights as tube.Recordthemassofthetrimmingblockandanyfragments
D5515–97 (2010)
ofthetrimmedpencilnottransferredintotheretorttubeasM6.
M6 = mass of the trimming block and any untransferred
To determine the accurate mass of coal in the coal pencil, it is
portion of the coal pencil, g.
essentialthatanyuntransferredfragmentsofthecoalpencilare
12.3 Calculate the mass of air-dried coal in the coal pencil,
weighed along with the trimming block.
M , as follows:
dry
M 5 M 2~M 3 % 3 0.01! (3)
10. Procedure dry wet wet H O
10.1 Clean the dilatometer retort and piston assembly.
where:
Firmly attach the retort tube plugs to the retort tubes. Check
M = mass of air-dried coal in the coal pencil, g;
dry
that the matched piston slides freely in the retort tube.
M = mass of the prepared coal pencil calculated in
wet
10.2 Prepare the coal pencils and load them into the retort
12.2; and
tubes as described in Section 9.
% = amount of water added to the coal calculated in
H2O
10.3 Load both retort tube and piston assemblies, charged
12.1.
with trimmed coal pencils, into the dilatometer furnace which
12.4 Calculate the char height, H , as follows:
c
is thermally stabilized at its 315°C setpoint. Start the tempera-
H 5 %D 3 0.6 1 60 (4)
c
ture control program immediately after loading is completed.
10.4 Attach the mechanism used to measure piston height
where:
and a
...