Standard Test Methods for Proximate Analysis of the Analysis Sample of Coal and Coke by Instrumental Procedures

SCOPE
1.1 These instrumental test methods cover the determination of moisture, volatile matter, and ash, and the calculation of fixed carbon in the analysis of coal and coke samples prepared in accordance with Method D2013 and Practice D346. Results obtained through the use of the instrumental tests have been shown to differ from those obtained with Test Methods D3173, D3174, and D3175 on some coals and cokes. Where a relative bias between the instrumental methods and Test Methods D3173, D3174, and D3175 for proximate analysis of coal and coke are shown to exist, the instrumental results shall be corrected or the instrument calibrated using samples of known proximate analysis. Test Methods D3173, D3174, and D3175 shall be considered the referee test methods. The instrumental test methods are not applicable to thermogravimetric analyzers utilizing microgram size samples.  
1.2 The moisture value determined is used for calculating other analytical results to a dry basis. When used in conjunction with the air dry loss moisture, as determined in accordance with Method D2013, Test Method D3302, or Practice D346, the calculated total moisture can be used to convert dry basis analytical results to the as-received basis.  
1.3 The result of the ash determinations can be applied in the ultimate analysis, Practice D3176.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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Historical
Publication Date
09-Sep-1998
Technical Committee
Drafting Committee
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ASTM D5142-90(1998) - Standard Test Methods for Proximate Analysis of the Analysis Sample of Coal and Coke by Instrumental Procedures
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NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: D 5142 – 90 (Reapproved 1998)
Standard Test Methods for
Proximate Analysis of the Analysis Sample of Coal and
Coke by Instrumental Procedures
This standard is issued under the fixed designation D 5142; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope D 3173 Test Method for Moisture in the Analysis Sample of
Coal and Coke
1.1 These instrumental test methods cover the determination
D 3174 Test Method for Ash in the Analysis Sample of Coal
of moisture, volatile matter, and ash, and the calculation of
and Coke from Coal
fixed carbon in the analysis of coal and coke samples prepared
D 3175 Test Method for Volatile Matter in the Analysis
in accordance with Method D 2013 and Practice D 346. Re-
Sample of Coal and Coke
sults obtained through the use of the instrumental tests have
D 3176 Practice for Ultimate Analysis of Coal and Coke
been shown to differ from those obtained with Test Methods
D 3180 Practice for Calculating Coal and Coke Analyses
D 3173, D 3174, and D 3175 on some coals and cokes. Where
from As-Determined to Different Bases
a relative bias between the instrumental methods and Test
D 3302 Test Method for Total Moisture in Coal
Methods D 3173, D 3174, and D 3175 for proximate analysis
of coal and coke are shown to exist, the instrumental results
3. Terminology
shall be corrected or the instrument calibrated using samples of
3.1 For definitions of terms used in this test method, refer to
known proximate analysis. Test Methods D 3173, D 3174, and
Terminology D 121.
D 3175 shall be considered the referee test methods. The
instrumental test methods are not applicable to thermogravi-
4. Summary of Test Methods
metric analyzers using microgram size samples.
4.1 Moisture is determined by establishing the loss in mass
1.2 The moisture value determined is used for calculating
of the analysis specimen of coal or coke when heated under
other analytical results to a dry basis. When used in conjunc-
rigidly controlled conditions of temperature, time, atmosphere,
tion with the air dry loss moisture, as determined in accordance
specimen mass, and equipment specifications.
with Method D 2013, Test Method D 3302, or Practice D 346,
4.2 Volatile matter is determined by measuring the loss in
the calculated total moisture can be used to convert dry basis
mass of the moist or dried analysis specimen of coal or coke
analytical results to the as-received basis.
when heated under rigidly controlled conditions. If appropriate,
1.3 The result of the ash determinations can be applied in
the measured mass loss establishes the volatile matter after
the ultimate analysis, Practice D 3176.
correcting for the moisture content.
1.4 This standard does not purport to address all of the
4.3 Ash is determined by measuring the mass of the residue
safety concerns, if any, associated with its use. It is the
remaining after burning the coal or coke specimen under
responsibility of the user of this standard to establish appro-
rigidly controlled conditions of specimen mass, temperature,
priate safety and health practices and determine the applica-
time, atmosphere, and equipment specifications.
bility of regulatory limitations prior to use.
4.4 In these test methods, moisture, volatile matter, and ash
2. Referenced Documents may be determined sequentially in a single instrumental
procedure. With some systems, the procedure consists of
2.1 ASTM Standards:
2 simply placing a specimen in the microprocessor-controlled
D 121 Terminology of Coal and Coke
instrument and initiating the automatic process of analyzing the
D 346 Practice for Collection and Preparation of Coke
2 specimen.
Samples for Laboratory Analysis
4.5 In other systems, the analytical process is manually
D 1757 Test Method for Sulfate Sulfur in Ash from Coal
2 controlled, although the instruments may have microprocessors
and Coke
2 to assist in controlling conditions of the instrument and for
D 2013 Method of Preparing Coal Samples for Analysis
calculations. The actual analytical process can vary from
instrument to instrument, but the overall process shall provide
These test methods are under the jurisdiction of ASTM Committee D-5 on Coal
for the determination of moisture, volatile matter, and ash as
and Coke and are the direct responsibility of Subcommittee D05.21 on Methods of
specified in 4.1, 4.2, and 4.3.
Analysis.
Current edition approved Nov. 30, 1990. Published April 1991.
4.6 Different procedures are described to permit conformity
Annual Book of ASTM Standards, Vol 05.05.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 5142
with differences in instrument design and for differences in a reactant gas, and to remove products of drying, devolatiliza-
sample behavior. tion, or combustion. Gases and acceptable flow rates for the
4.7 Where a relative bias between these test methods and different determinations are as follows:
other ASTM test methods for the proximate analysis of coal
Flow Rate, Furnace
Determination of Gas
Volume per Minute
and coke has been shown to exist (12.2.1), the instrument used
in these test methods must be calibrated using specimens of
Moisture nitrogen or air 2–4
A
known composition covering the range of parameters being
Ash oxygen 0.4–0.8
air 2–4
determined.
Volatile matter nitrogen 2–4
A
This oxygen flow is chemically equivalent to 2 to 4 volume changes of air per
5. Significance and Use
minute.
5.1 Moisture, as determined by the instrumental test 6.2 Crucibles, with covers, of a convenient form that allows
the moisture and volatile matter, or moisture and ash, or all
method, is used for calculating other analytical results to a
moisture-free basis using procedures in Practice D 3180. Mois- three determinations to be made on the same specimen, shall be
used. The crucibles may be made of fused silica with self-
ture percent determined by this test method may be used in
conjunction with the air-dry moisture loss determined in sealing covers that have ground glass seals or of porcelain with
self-sealing covers. The covers shall allow the rapid escape of
Method D 2013 and Test Method D 3302 to determine total
moisture in coal. Total moisture is used for calculating other gases during the determination of volatile matter. All crucibles
used shall have the dimensions specified by the instrument
analytical results to an as-received basis using Practice D 3180.
5.2 Ash yield, as determined by this test method, is the manufacturer.
residue remaining after burning the coal and coke samples. 6.3 Balance, sensitive to 0.1 mg. The balance may be an
5.3 Volatile matter yield, when determined as herein de- internal balance and an integral part of the instrument used for
scribed, may be used to (1) establish the rank of coals, (2) determining the moisture, volatile matter, and ash, or it may be
indicate coke yield on carbonization, (3) provide the basis for a separate piece of apparatus that may not be interfaced with
purchasing and selling, or (4) establish burning characteristics. the instrument.
5.4 Fixed carbon is a calculated value. It is the difference 6.4 The instrumental system in its entirety shall be operated
between 100 and the sum of the percent moisture, ash, and in strict accordance with the manufacturer’s operating instruc-
volatile matter. All percents shall be on the moisture reference tions.
base. 6.5 Venting Equipment—Combustion and volatile gases
5.5 Moisture, ash, volatile matter, and fixed carbon percents evolved during the test procedures shall be vented from the
constitute the proximate analysis of coal and coke. laboratory and suitable venting equipment shall be installed in
the vicinity of the apparatus.
NOTE 1—The ash obtained differs in composition and amount from the
mineral constituents present in the original coal. Incineration causes an
7. Analysis Sample
expulsion of all water, the loss of carbon dioxide from carbonates, the
7.1 Obtain the sample for coal in accordance with Method
conversion of iron pyrite into iron oxides and sulfur oxides, and other
D 2013 and the sample for coke in accordance with Practice
chemical reactions. Ash yield, as determined by this test method, can
differ from the amount of ash produced in furnace operations or other
D 346. Obtain the analysis sample by pulverizing the material
combustion systems because incineration conditions influence the chem-
to a fineness to pass the 250-μm (No. 60) sieve.
istry and amount of ash.
8. Reagents and Materials
6. Apparatus
8.1 Dry Gas—Nitrogen (>99.5 % purity) or air, dried to a
6.1 Furnace or Oven—The primary apparatus shall consist
moisture content of 1.9 mg/L or less (dew point −10°C or less)
of a furnace or oven with a cavity large enough to accept
to be used to purge the drying oven. Any desiccant or drying
crucibles containing the specimens. The furnace or oven shall
method capable of achieving this degree of dryness is suitable.
be constructed so the cavity is surrounded by a suitable
(See Reagent section of Test Method D 3173.)
refactory and insulated so as to develop a uniform temperature
in all parts of the cavity but with a minimum free space. The 9. Procedure
furnace shall be capable of being heated rapidly at a rate of
9.1 Some instruments allow for the determination of mois-
50°C/min from ambient to 950°C.
ture, volatile matter, and ash in sequence using the same
6.1.1 The temperatures within the cavity shall be monitored
specimen. Alternatively, some instruments, or components of
and maintained at values that are specific to each of the
the instruments, may be used to carry out separate determina-
determinations. Temperatures, as measured in crucibles located
tions of moisture, volatile matter, or ash using separate
throughout the cavity shall be maintained within the following
specimens of coal or coke.
limits:
9.2 Heat new crucibles and covers (see 9.2.1) for use in
Temperature, °C
these test methods under the conditions of the test and cool
Determination of min max
before use. For each test, weigh a prepared crucible (Note 2).
Add approximately1gof coal or coke to the crucible and then
Moisture 104 110
Ash 700 750
weigh the crucible and specimen. Make all weighings to the
Volatile matter 930 970
nearest 0.1 mg. Transfer the specimen from the sample bottle
6.1.2 Provisions shall be made to introduce a sweep gas or to the crucible quickly to minimize the exposure of the
NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 5142
specimen to the atmosphere during the weighing process. Use instrument will then make weighings at regular intervals while
crucible covers to protect the specimen before and after the the temperature of the furnace is raised at a rate of 50°C/min to
moisture determination. Use crucible covers during the deter- 950 6 20°C and held for 7 min. The instrument uses the
mination of the volatile matter. Weigh the cover with the weight of the specimen at the end of the 7-min period in the
crucible and specimen for this test. calculation of the volatile matter.
9.4.3 For instruments without an internal balance, weigh the
9.2.1 The cover shall fit closely enough so that the carbon
crucibles, specimens, and covers and then place them in the
deposit from bituminous, subbituminous, and lignitic coals
furnace. Raise the temperature of the furnace at a rate of
does not burn away from the under side of the cover.
50°C/min to 950 6 20°C and hold for 7 min. Then remove the
NOTE 2—In microprocessor-controlled instruments, the specimen
crucibles from the furnace, without disturbing the covers, and
weights are recorded by the microprocessor and retained for further
allow to cool to ambient temperature in a desiccator. Weigh the
calculations. In instruments with internal balances, or with those inter-
crucibles and covers as soon as possible.
faced to a balance, these weights are automatically recorded. For some
instruments without these features, the specimen weights may be entered
NOTE 3—Caution: With some strongly caking low-volatile and
manually into the microprocessor memory.
medium-volatile bituminous coals, the coke button may explode as a
result of the rapid liberation of volatile matter within the button. This is
9.3 Moisture Determination:
usually designated as popping. Such popping may blow the lid off the
9.3.1 For moisture determinations, heat the weighed
crucible and cause mechanical losses of the coked material. When such
samples in crucibles without the covers in the drying oven at
popping is observed, the determination should be rejected and the test
104 to 110°C. Various modes of operation are possible depend-
repeated until popping does not occur or Alternative Procedure No. 2 for
ing on the instrument used and the manner in which the
volatile matter is used (9.5.2).
determination is completed.
9.5 Alternative Procedures for Volatile Matter:
9.3.2 Automated instruments with an internal balance that
9.5.1 Alternative Procedure No. 1—Place the weighed cru-
can weigh the specimen repeatedly during the determination
cibles with specimens and self-sealing covers in the furnace
can be programmed to terminate the test when the specimens
preheated to 950 6 20°C. Leave the crucibles in the furnace
and crucibles have reached a constant weight. Typically,
for 7 min and then remove and allow to cool without disturbing
crucibles are weighed automatically at 3-min intervals, and the
the covers. Weigh the crucibles with the covers as soon as
analysis is complete when two successive weighings agree
possible after cooling to ambient temperature in a desiccator.
within the plateau deviation specified for the instrument. Use
9.5.2 Alternative Procedure No. 2—Use this procedure if
nitrogen with a purity >99.5 % and a moisture content of 1.9
Alternative Procedure No. 1 causes excessive swelling, ashing,
mg/L or less (dew point of −10°C or less) as the drying gas in
or mechanical losses of specimens. In this procedure, place the
the oven (see 8.1). Some models of this type of instrument also
weighed crucibles with specimens and self-sealing covers in
allow for moisture determination by heating the specimen for
the cold furnace and heat to a temperature of 600
...

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