ASTM D7582-15(2023)
(Test Method)Standard Test Methods for Proximate Analysis of Coal and Coke by Macro Thermogravimetric Analysis
Standard Test Methods for Proximate Analysis of Coal and Coke by Macro Thermogravimetric Analysis
SIGNIFICANCE AND USE
5.1 Moisture, as determined by this instrumental test method, is used for calculating other analytical results to a dry basis using procedures in Practice D3180.
5.2 Moisture can be used in conjunction with the air-dry moisture loss determined by Test Method D3302 to determine total moisture in coal. Total moisture is used for calculating other analytical results to an as-received basis using Practice D3180.
5.3 Ash yield is the residue remaining after heating the coal and coke samples (see Note 1).
Note 1: The ash obtained differs in composition and amount from the mineral constituents present in the original coal. Combustion causes an expulsion of all water, the loss of carbon dioxide from carbonates, the conversion of iron pyrite into iron oxides and sulfur oxides, and other chemical reactions. Ash yield, as determined by this test method, can differ from the amount of ash produced in furnace operations or other combustion systems because combustion conditions influence the chemistry and amount of ash.
5.4 Ash yield is used, (1) as a parameter for evaluating sampling procedures and coal cleaning processes, (2) in the ultimate analysis calculation of oxygen by difference using Practice D3176, (3) in calculations including material balance, reactivity and yields of products relevant to coal conversion processes such as gasification and liquefaction, (4) in calculations to estimate the loading on electrostatic precipitators and on the fly ash and bottom ash disposal systems as well as erosion rates on boiler systems.
5.5 Volatile matter yield, when determined as herein described, may be used to (1) indicate coke yield on carbonization, (2) provide the basis for purchasing and selling, or (3) establish combustion characteristics.
5.6 Fixed carbon is a calculated value. It is the difference between 100 and the sum of the percent moisture, ash, and volatile matter. All percents shall be on the same moisture reference base.
5.7 Moisture, ash, and v...
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 Practice D2013 and Practice D346.
1.2 These instrumental test methods are not applicable to thermogravimetric analyzers using microgram size samples.
1.3 Test Methods D3173, D3174, and D3175 shall be considered the referee test methods.
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 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.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
General Information
Relations
Buy Standard
Standards Content (Sample)
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D7582 − 15 (Reapproved 2023)
Standard Test Methods for
Proximate Analysis of Coal and Coke by Macro
Thermogravimetric Analysis
This standard is issued under the fixed designation D7582; 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.
1. Scope D3174 Test Method for Ash in the Analysis Sample of Coal
and Coke from Coal
1.1 These instrumental test methods cover the determination
D3175 Test Method for Volatile Matter in the Analysis
of moisture, volatile matter, and ash, and the calculation of
Sample of Coal and Coke
fixed carbon in the analysis of coal and coke samples prepared
D3176 Practice for Ultimate Analysis of Coal and Coke
in accordance with Practice D2013 and Practice D346.
D3180 Practice for Calculating Coal and Coke Analyses
1.2 These instrumental test methods are not applicable to
from As-Determined to Different Bases
thermogravimetric analyzers using microgram size samples.
D3302 Test Method for Total Moisture in Coal
1.3 Test Methods D3173, D3174, and D3175 shall be D5016 Test Method for Total Sulfur in Coal and Coke
Combustion Residues Using a High-Temperature Tube
considered the referee test methods.
Furnace Combustion Method with Infrared Absorption
1.4 The values stated in SI units are to be regarded as
E691 Practice for Conducting an Interlaboratory Study to
standard. No other units of measurement are included in this
Determine the Precision of a Test Method
standard.
1.5 This standard does not purport to address all of the
3. Terminology
safety concerns, if any, associated with its use. It is the
3.1 For definitions of terms used in this test method, refer to
responsibility of the user of this standard to establish appro-
Terminology D121.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
4. Summary of Test Method
1.6 This international standard was developed in accor-
dance with internationally recognized principles on standard- 4.1 In thermogravimetric analysis, the mass of a sample in
ization established in the Decision on Principles for the a controlled atmosphere is recorded repeatedly as a function of
Development of International Standards, Guides and Recom- temperature or time, or both. In macro thermogravimetric
mendations issued by the World Trade Organization Technical analysis, a sample size of approximately 1 g is used. All mass
Barriers to Trade (TBT) Committee. measurements are conducted by the system. In a typical
analysis, the temperature is normally ramped from ambient to
2. Referenced Documents
a specific temperature and held at that temperature for a
2.1 ASTM Standards:
prescribed length of time. The mass change is recorded
D121 Terminology of Coal and Coke
repeatedly during the entire procedure. For the thermogravi-
D346 Practice for Collection and Preparation of Coke
metric analysis of coal and coke samples the moisture and ash
Samples for Laboratory Analysis
analyses are complete when the sample reaches a constant
D2013 Practice for Preparing Coal Samples for Analysis
mass as defined in the instrumental operating parameters.
D3173 Test Method for Moisture in the Analysis Sample of
Alternatively, the measurement of moisture and ash can be
Coal and Coke
considered complete after heating the sample for a fixed period
of time. In the volatile matter analysis, the samples are weighed
This test method is under the jurisdiction of ASTM Committee D05 on Coal
after heating to 950 °C and held at this temperature for 7 min.
and Coke and is the direct responsibility of Subcommittee D05.21 on Methods of
Analysis. 4.2 Moisture is determined by measuring the loss in mass of
Current edition approved Dec. 1, 2023. Published December 2023. Originally
the analysis specimen of coal or coke when heated under
approved in 2009. Last previous edition approved in 2015 as D7582 – 15. DOI:
specified conditions of temperature, time, atmosphere, speci-
10.1520/D7582-15R23.
men mass, and equipment specifications.
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
4.3 Volatile matter is determined by measuring the loss in
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. mass of the analysis specimen of coal or coke when heated
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7582 − 15 (2023)
under rigidly controlled conditions. The measured mass loss is 5.4 Ash yield is used, (1) as a parameter for evaluating
used to calculate the volatile matter after correcting for the sampling procedures and coal cleaning processes, (2) in the
moisture content. ultimate analysis calculation of oxygen by difference using
Practice D3176, (3) in calculations including material balance,
4.4 Ash is determined by measuring the mass of the residue
reactivity and yields of products relevant to coal conversion
remaining after burning the coal or coke specimen under
processes such as gasification and liquefaction, (4) in calcula-
specified conditions of specimen mass, temperature, time,
tions to estimate the loading on electrostatic precipitators and
atmosphere, and equipment specifications.
on the fly ash and bottom ash disposal systems as well as
4.5 In these test methods, moisture, volatile matter, and ash
erosion rates on boiler systems.
can be determined sequentially in a single instrumental proce-
5.5 Volatile matter yield, when determined as herein
dure. Another procedure allows the moisture and ash to be
described, may be used to (1) indicate coke yield on
determined sequentially. Moisture and ash can also be deter-
carbonization, (2) provide the basis for purchasing and selling,
mined in separate determinations. Ruggedness testing and past
or (3) establish combustion characteristics.
experiences have shown the volatile matter values determined
on samples without first determining the moisture (drying the 5.6 Fixed carbon is a calculated value. It is the difference
sample) are always higher than those of the dried samples. between 100 and the sum of the percent moisture, ash, and
volatile matter. All percents shall be on the same moisture
4.6 Good laboratory practice requires checking for biases
reference base.
between analytical methods for contractual compliance. When
only a few coal types will be routinely tested, the instrument 5.7 Moisture, ash, and volatile matter are three of the
used in these test methods must be shown to yield results, for principal parameters used for assessing the quality of coal.
the coal(s) to be tested, that are equivalent to those obtained
6. Interferences
using Test Methods D3173, D3174, and D3175. If they are
found to be not equivalent, either the instrument used is
6.1 There are no known interferences for these test methods.
calibrated or the instrumental results are adjusted to establish
and maintain equivalence. Alternatively, when a broad spec- 7. Apparatus
trum of coal types will be tested, the instrument used in these
7.1 Macro Thermogravimetric Analyzer (Macro TGA)—A
test methods shall be calibrated using certified reference
computer controlled apparatus consisting of a furnace with a
materials of known composition covering the range of param-
cavity large enough to accept crucibles containing test speci-
eters being determined. The certified values shall be estab-
mens that meet the minimum mass requirements of the
lished using Test Methods D3173, D3174, and D3175. Section
procedure. The macro TGA system can accommodate multiple
16.2 lists a number of biases that have been shown to exist
crucibles, allowing for continuous analysis with one crucible
between instrumental results. Other biases, of unknown mag-
reserved for the blank or reference crucible. The furnace is
nitude and sign, may exist for other coals.
constructed so the cavity is surrounded by a suitable refractory
and insulated so as to develop a uniform temperature in all
5. Significance and Use
parts of the cavity, but with a minimum free space. The furnace
5.1 Moisture, as determined by this instrumental test shall be capable of being heated rapidly (30 °C ⁄min to
45 °C ⁄min from ambient to 950 °C. The temperature shall be
method, is used for calculating other analytical results to a dry
basis using procedures in Practice D3180. monitored and maintained at values specified for each deter-
mination. The system shall have an integrated balance capable
5.2 Moisture can be used in conjunction with the air-dry
of weighing the crucibles and test specimens repeatedly
moisture loss determined by Test Method D3302 to determine
throughout the analysis. All mass measurements are conducted
total moisture in coal. Total moisture is used for calculating
and recorded by the system. The sensitivity of the balance shall
other analytical results to an as-received basis using Practice
be at least 0.1 mg. Provision shall be made to introduce gases
D3180.
specified for this standard and to remove products of drying,
5.3 Ash yield is the residue remaining after heating the coal
devolatilization, and combustion. The macro TGA system shall
and coke samples (see Note 1).
have a venting fan, tolerant of hot product gases, to efficiently
remove the exhaust gases.
NOTE 1—The ash obtained differs in composition and amount from the
mineral constituents present in the original coal. Combustion causes an
7.2 Crucibles—with covers of composition and dimensions
expulsion of all water, the loss of carbon dioxide from carbonates, the
specified for the instrument by the instrument manufacturer.
conversion of iron pyrite into iron oxides and sulfur oxides, and other
The covers shall fit closely enough so that the carbon deposit
chemical reactions. Ash yield, as determined by this test method, can
differ from the amount of ash produced in furnace operations or other
from bituminous, subbituminous, and lignitic coals does not
combustion systems because combustion conditions influence the chem-
burn away from the underside of the cover during the deter-
istry and amount of ash.
mination of the volatile matter
8. Reagents and Materials
Riley J.T., Yanes E.G, Marsh M., Lawrenz D., and Eichenbaum L., “Coal and
8.1 Drying Gas—Nitrogen (99.5 % purity), Argon (99.5 %
Coke Volatile Matter Determination and Reconciliation of Differences in Yields
purity) or air, dried to a moisture content of 1.9 mg/L or less
Determined by Two ASTM Methods,” J. Testing and Evaluation, 2010, 38(4),
458-466. (dew point –10 °C or less).
D7582 − 15 (2023)
8.2 Inert Gas—Nitrogen (99.5 % purity) or Argon (99.5 % The calibration shall be performed at the same furnace ramp
purity). temperature as that used for the analysis. Do not use coal
reference material(s) for coke volatile matter calibration. Do
8.3 Oxidizing Gas—Oxygen (99.5 % purity) or air.
not use coke reference material(s) for coal volatile matter
8.4 Certified Reference Materials—Coal or coke material(s)
calibration. Use coal reference material(s) with a certified
meeting the requirements of 10.1, with a certificate of analysis
reference value and uncertainty based on measurements made
specifying the reference value and the uncertainty of the
employing Test Methods D3173, D3174, and D3175 to cali-
reference value. Reference material(s) can be employed to
brate this test method.
calibrate the instrument for the determination of volatile
matter. Certified reference values shall have been established
13. Procedure
using Test Methods D3173, D3174, and D3175. Reference
13.1 The determination of moisture, followed by volatile
materials used for the calibration of volatile matter shall
matter followed by ash can be carried out in sequence using the
include information on the certificate of analysis detailing the
same test specimen. Alternatively, the determination of
method(s) employed to determine volatile matter of the refer-
moisture, volatile matter, or ash can be carried out separately
ence material.
on test specimens of coal or coke.
9. Hazards
13.2 Sequential Determination of Moisture, Volatile Matter
9.1 The user shall insure acceptable documented safety
and Ash:
procedures are in place for the handling of all reagents and test 13.2.1 After verifying instrument setup according to Section
materials and for the operation of laboratory equipment speci-
11 on the preparation of apparatus, load and tare the crucibles.
fied for these test methods. Add approximately 1 g of coal or coke to the crucible in the
balance position and weigh immediately before advancing the
9.2 Venting Equipment—Install equipment in the vicinity of
next crucible. Transfer the test specimen from the sample bottle
the apparatus to vent combustion and volatile gases evolved
to the crucible quickly to minimize the exposure of the test
during the test procedures from the laboratory.
specimen to the atmosphere during the initial weighing pro-
10. Analysis Sample cess.
13.2.2 For moisture determinations, heat the weighed test
10.1 The analysis sample shall be the material pulverized to
specimens in crucibles without the covers at 107 °C 6 3 °C.
pass a 250-μm (No. 60) sieve in accordance with Practice
Use a drying gas flow rate of 0.4 to 1.4 furnace volume changes
D2013 or Practice D346.
per minute (see 8.1). Program the instrument to terminate the
11. Preparation of Apparatus test when the test specimens and crucibles have reached a
constant mass (see 11.3). Alternatively, program the instrument
11.1 Verify the instrument can meet all specifications in the
to allow for moisture determination by heating the test speci-
standard with respect to gas flows, heating rates, and balance
mens for 1 h.
sensitivity prior to use. Condition the instrument after initial
13.2.3 For volatile matter determinations following the
setup, or repairs, by conducting a run through a complete cycle
moisture analysis, place covers on the crucibles in the TGA
without samples.
carousel (the covers are placed automatically in some systems
11.2 Condition new crucibles and covers for use in these test
and manually in others). Program the instrument to reweigh the
methods by heating under the same conditions of the test and
crucibles, with specimens inside, and covers in place before
cool before use.
initiating the volatile matter part of the cycle
...
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D7582 − 15 (Reapproved 2023)
Standard Test Methods for
Proximate Analysis of Coal and Coke by Macro
Thermogravimetric Analysis
This standard is issued under the fixed designation D7582; 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.
1. Scope D3174 Test Method for Ash in the Analysis Sample of Coal
and Coke from Coal
1.1 These instrumental test methods cover the determination
D3175 Test Method for Volatile Matter in the Analysis
of moisture, volatile matter, and ash, and the calculation of
Sample of Coal and Coke
fixed carbon in the analysis of coal and coke samples prepared
D3176 Practice for Ultimate Analysis of Coal and Coke
in accordance with Practice D2013 and Practice D346.
D3180 Practice for Calculating Coal and Coke Analyses
1.2 These instrumental test methods are not applicable to
from As-Determined to Different Bases
thermogravimetric analyzers using microgram size samples.
D3302 Test Method for Total Moisture in Coal
D5016 Test Method for Total Sulfur in Coal and Coke
1.3 Test Methods D3173, D3174, and D3175 shall be
considered the referee test methods. Combustion Residues Using a High-Temperature Tube
Furnace Combustion Method with Infrared Absorption
1.4 The values stated in SI units are to be regarded as
E691 Practice for Conducting an Interlaboratory Study to
standard. No other units of measurement are included in this
Determine the Precision of a Test Method
standard.
1.5 This standard does not purport to address all of the
3. Terminology
safety concerns, if any, associated with its use. It is the
3.1 For definitions of terms used in this test method, refer to
responsibility of the user of this standard to establish appro-
Terminology D121.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
4. Summary of Test Method
1.6 This international standard was developed in accor-
dance with internationally recognized principles on standard- 4.1 In thermogravimetric analysis, the mass of a sample in
ization established in the Decision on Principles for the
a controlled atmosphere is recorded repeatedly as a function of
Development of International Standards, Guides and Recom- temperature or time, or both. In macro thermogravimetric
mendations issued by the World Trade Organization Technical analysis, a sample size of approximately 1 g is used. All mass
Barriers to Trade (TBT) Committee. measurements are conducted by the system. In a typical
analysis, the temperature is normally ramped from ambient to
2. Referenced Documents
a specific temperature and held at that temperature for a
2.1 ASTM Standards:
prescribed length of time. The mass change is recorded
D121 Terminology of Coal and Coke
repeatedly during the entire procedure. For the thermogravi-
D346 Practice for Collection and Preparation of Coke
metric analysis of coal and coke samples the moisture and ash
Samples for Laboratory Analysis
analyses are complete when the sample reaches a constant
D2013 Practice for Preparing Coal Samples for Analysis
mass as defined in the instrumental operating parameters.
D3173 Test Method for Moisture in the Analysis Sample of
Alternatively, the measurement of moisture and ash can be
Coal and Coke
considered complete after heating the sample for a fixed period
of time. In the volatile matter analysis, the samples are weighed
This test method is under the jurisdiction of ASTM Committee D05 on Coal
after heating to 950 °C and held at this temperature for 7 min.
and Coke and is the direct responsibility of Subcommittee D05.21 on Methods of
Analysis. 4.2 Moisture is determined by measuring the loss in mass of
Current edition approved Dec. 1, 2023. Published December 2023. Originally
the analysis specimen of coal or coke when heated under
approved in 2009. Last previous edition approved in 2015 as D7582 – 15. DOI:
specified conditions of temperature, time, atmosphere, speci-
10.1520/D7582-15R23.
men mass, and equipment specifications.
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
4.3 Volatile matter is determined by measuring the loss in
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. mass of the analysis specimen of coal or coke when heated
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7582 − 15 (2023)
under rigidly controlled conditions. The measured mass loss is 5.4 Ash yield is used, (1) as a parameter for evaluating
used to calculate the volatile matter after correcting for the sampling procedures and coal cleaning processes, (2) in the
moisture content. ultimate analysis calculation of oxygen by difference using
Practice D3176, (3) in calculations including material balance,
4.4 Ash is determined by measuring the mass of the residue
reactivity and yields of products relevant to coal conversion
remaining after burning the coal or coke specimen under
processes such as gasification and liquefaction, (4) in calcula-
specified conditions of specimen mass, temperature, time,
tions to estimate the loading on electrostatic precipitators and
atmosphere, and equipment specifications.
on the fly ash and bottom ash disposal systems as well as
4.5 In these test methods, moisture, volatile matter, and ash
erosion rates on boiler systems.
can be determined sequentially in a single instrumental proce-
5.5 Volatile matter yield, when determined as herein
dure. Another procedure allows the moisture and ash to be
described, may be used to (1) indicate coke yield on
determined sequentially. Moisture and ash can also be deter-
carbonization, (2) provide the basis for purchasing and selling,
mined in separate determinations. Ruggedness testing and past
or (3) establish combustion characteristics.
experiences have shown the volatile matter values determined
on samples without first determining the moisture (drying the 5.6 Fixed carbon is a calculated value. It is the difference
sample) are always higher than those of the dried samples. between 100 and the sum of the percent moisture, ash, and
volatile matter. All percents shall be on the same moisture
4.6 Good laboratory practice requires checking for biases
reference base.
between analytical methods for contractual compliance. When
only a few coal types will be routinely tested, the instrument 5.7 Moisture, ash, and volatile matter are three of the
used in these test methods must be shown to yield results, for principal parameters used for assessing the quality of coal.
the coal(s) to be tested, that are equivalent to those obtained
6. Interferences
using Test Methods D3173, D3174, and D3175. If they are
found to be not equivalent, either the instrument used is
6.1 There are no known interferences for these test methods.
calibrated or the instrumental results are adjusted to establish
7. Apparatus
and maintain equivalence. Alternatively, when a broad spec-
trum of coal types will be tested, the instrument used in these
7.1 Macro Thermogravimetric Analyzer (Macro TGA)—A
test methods shall be calibrated using certified reference
computer controlled apparatus consisting of a furnace with a
materials of known composition covering the range of param-
cavity large enough to accept crucibles containing test speci-
eters being determined. The certified values shall be estab-
mens that meet the minimum mass requirements of the
lished using Test Methods D3173, D3174, and D3175. Section
procedure. The macro TGA system can accommodate multiple
16.2 lists a number of biases that have been shown to exist
crucibles, allowing for continuous analysis with one crucible
between instrumental results. Other biases, of unknown mag-
reserved for the blank or reference crucible. The furnace is
nitude and sign, may exist for other coals.
constructed so the cavity is surrounded by a suitable refractory
and insulated so as to develop a uniform temperature in all
5. Significance and Use
parts of the cavity, but with a minimum free space. The furnace
shall be capable of being heated rapidly (30 °C ⁄min to
5.1 Moisture, as determined by this instrumental test
method, is used for calculating other analytical results to a dry 45 °C ⁄min from ambient to 950 °C. The temperature shall be
monitored and maintained at values specified for each deter-
basis using procedures in Practice D3180.
mination. The system shall have an integrated balance capable
5.2 Moisture can be used in conjunction with the air-dry
of weighing the crucibles and test specimens repeatedly
moisture loss determined by Test Method D3302 to determine
throughout the analysis. All mass measurements are conducted
total moisture in coal. Total moisture is used for calculating
and recorded by the system. The sensitivity of the balance shall
other analytical results to an as-received basis using Practice
be at least 0.1 mg. Provision shall be made to introduce gases
D3180.
specified for this standard and to remove products of drying,
5.3 Ash yield is the residue remaining after heating the coal
devolatilization, and combustion. The macro TGA system shall
and coke samples (see Note 1).
have a venting fan, tolerant of hot product gases, to efficiently
remove the exhaust gases.
NOTE 1—The ash obtained differs in composition and amount from the
mineral constituents present in the original coal. Combustion causes an
7.2 Crucibles—with covers of composition and dimensions
expulsion of all water, the loss of carbon dioxide from carbonates, the
specified for the instrument by the instrument manufacturer.
conversion of iron pyrite into iron oxides and sulfur oxides, and other
The covers shall fit closely enough so that the carbon deposit
chemical reactions. Ash yield, as determined by this test method, can
differ from the amount of ash produced in furnace operations or other from bituminous, subbituminous, and lignitic coals does not
combustion systems because combustion conditions influence the chem-
burn away from the underside of the cover during the deter-
istry and amount of ash.
mination of the volatile matter
8. Reagents and Materials
Riley J.T., Yanes E.G, Marsh M., Lawrenz D., and Eichenbaum L., “Coal and
8.1 Drying Gas—Nitrogen (99.5 % purity), Argon (99.5 %
Coke Volatile Matter Determination and Reconciliation of Differences in Yields
purity) or air, dried to a moisture content of 1.9 mg/L or less
Determined by Two ASTM Methods,” J. Testing and Evaluation, 2010, 38(4),
458-466. (dew point –10 °C or less).
D7582 − 15 (2023)
8.2 Inert Gas—Nitrogen (99.5 % purity) or Argon (99.5 % The calibration shall be performed at the same furnace ramp
purity). temperature as that used for the analysis. Do not use coal
reference material(s) for coke volatile matter calibration. Do
8.3 Oxidizing Gas—Oxygen (99.5 % purity) or air.
not use coke reference material(s) for coal volatile matter
8.4 Certified Reference Materials—Coal or coke material(s)
calibration. Use coal reference material(s) with a certified
meeting the requirements of 10.1, with a certificate of analysis
reference value and uncertainty based on measurements made
specifying the reference value and the uncertainty of the
employing Test Methods D3173, D3174, and D3175 to cali-
reference value. Reference material(s) can be employed to
brate this test method.
calibrate the instrument for the determination of volatile
matter. Certified reference values shall have been established
13. Procedure
using Test Methods D3173, D3174, and D3175. Reference
13.1 The determination of moisture, followed by volatile
materials used for the calibration of volatile matter shall
matter followed by ash can be carried out in sequence using the
include information on the certificate of analysis detailing the
same test specimen. Alternatively, the determination of
method(s) employed to determine volatile matter of the refer-
moisture, volatile matter, or ash can be carried out separately
ence material.
on test specimens of coal or coke.
9. Hazards
13.2 Sequential Determination of Moisture, Volatile Matter
9.1 The user shall insure acceptable documented safety and Ash:
procedures are in place for the handling of all reagents and test
13.2.1 After verifying instrument setup according to Section
materials and for the operation of laboratory equipment speci- 11 on the preparation of apparatus, load and tare the crucibles.
fied for these test methods.
Add approximately 1 g of coal or coke to the crucible in the
balance position and weigh immediately before advancing the
9.2 Venting Equipment—Install equipment in the vicinity of
next crucible. Transfer the test specimen from the sample bottle
the apparatus to vent combustion and volatile gases evolved
to the crucible quickly to minimize the exposure of the test
during the test procedures from the laboratory.
specimen to the atmosphere during the initial weighing pro-
10. Analysis Sample cess.
13.2.2 For moisture determinations, heat the weighed test
10.1 The analysis sample shall be the material pulverized to
specimens in crucibles without the covers at 107 °C 6 3 °C.
pass a 250-µm (No. 60) sieve in accordance with Practice
Use a drying gas flow rate of 0.4 to 1.4 furnace volume changes
D2013 or Practice D346.
per minute (see 8.1). Program the instrument to terminate the
test when the test specimens and crucibles have reached a
11. Preparation of Apparatus
constant mass (see 11.3). Alternatively, program the instrument
11.1 Verify the instrument can meet all specifications in the
to allow for moisture determination by heating the test speci-
standard with respect to gas flows, heating rates, and balance
mens for 1 h.
sensitivity prior to use. Condition the instrument after initial
13.2.3 For volatile matter determinations following the
setup, or repairs, by conducting a run through a complete cycle
moisture analysis, place covers on the crucibles in the TGA
without samples.
carousel (the covers are placed automatically in some systems
11.2 Condition new crucibles and covers for use in these test
and manually in others). Program the instrument to reweigh the
methods by heating under the same conditions of the test and
crucibles, with specimens inside, and covers in place before
cool before use.
initiating the volatile matter part of the cycle.
13.2.3.1 To provide an inert atmosphere, use nitrogen or
11.3 The macro TGA system can be programmed to termi-
nate the measu
...
This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D7582 − 15 D7582 − 15 (Reapproved 2023)
Standard Test Methods for
Proximate Analysis of Coal and Coke by Macro
Thermogravimetric Analysis
This standard is issued under the fixed designation D7582; 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.
1. 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 Practice D2013 and Practice D346.
1.2 These instrumental test methods are not applicable to thermogravimetric analyzers using microgram size samples.
1.3 Test Methods D3173, D3174, and D3175 shall be considered the referee test methods.
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 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, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.5 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.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
D121 Terminology of Coal and Coke
D346 Practice for Collection and Preparation of Coke Samples for Laboratory Analysis
D2013 Practice for Preparing Coal Samples for Analysis
D3173 Test Method for Moisture in the Analysis Sample of Coal and Coke
D3174 Test Method for Ash in the Analysis Sample of Coal and Coke from Coal
D3175 Test Method for Volatile Matter in the Analysis Sample of Coal and Coke
D3176 Practice for Ultimate Analysis of Coal and Coke
This test method is under the jurisdiction of ASTM Committee D05 on Coal and Coke and is the direct responsibility of Subcommittee D05.21 on Methods of Analysis.
Current edition approved May 15, 2015Dec. 1, 2023. Published June 2015December 2023. Originally approved in 2009. Last previous edition approved in 20122015 as
D7582D7582 – 15.-12. DOI: 10.1520/D7582–15.10.1520/D7582-15R23.
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 Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7582 − 15 (2023)
D3180 Practice for Calculating Coal and Coke Analyses from As-Determined to Different Bases
D3302 Test Method for Total Moisture in Coal
D5016 Test Method for Total Sulfur in Coal and Coke Combustion Residues Using a High-Temperature Tube Furnace
Combustion Method with Infrared Absorption
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
3. Terminology
3.1 For definitions of terms used in this test method, refer to Terminology D121.
4. Summary of Test Method
4.1 In thermogravimetric analysis, the mass of a sample in a controlled atmosphere is recorded repeatedly as a function of
temperature or time, or both. In macro thermogravimetric analysis, a sample size of approximately 1 g is used. All mass
measurements are conducted by the system. In a typical analysis, the temperature is normally ramped from ambient to a specific
temperature and held at that temperature for a prescribed length of time. The mass change is recorded repeatedly during the entire
procedure. For the thermogravimetric analysis of coal and coke samples the moisture and ash analyses are complete when the
sample reaches a constant mass as defined in the instrumental operating parameters. Alternatively, the measurement of moisture
and ash can be considered complete after heating the sample for a fixed period of time. In the volatile matter analysis, the samples
are weighed after heating to 950°C950 °C and held at this temperature for 7 min.7 min.
4.2 Moisture is determined by measuring the loss in mass of the analysis specimen of coal or coke when heated under specified
conditions of temperature, time, atmosphere, specimen mass, and equipment specifications.
4.3 Volatile matter is determined by measuring the loss in mass of the analysis specimen of coal or coke when heated under rigidly
controlled conditions. The measured mass loss is used to calculate the volatile matter after correcting for the moisture content.
4.4 Ash is determined by measuring the mass of the residue remaining after burning the coal or coke specimen under specified
conditions of specimen mass, temperature, time, atmosphere, and equipment specifications.
4.5 In these test methods, moisture, volatile matter, and ash can be determined sequentially in a single instrumental procedure.
Another procedure allows the moisture and ash to be determined sequentially. Moisture and ash can also be determined in separate
determinations. Ruggedness testing and past experiences have shown the volatile matter values determined on samples without first
determining the moisture (drying the sample) are always higher than those of the dried samples.
4.6 Good laboratory practice requires checking for biases between analytical methods for contractual compliance. When only a
few coal types will be routinely tested, the instrument used in these test methods must be shown to yield results, for the coal(s)
to be tested, that are equivalent to those obtained using Test Methods D3173, D3174, and D3175. If they are found to be not
equivalent, either the instrument used is calibrated or the instrumental results are adjusted to establish and maintain equivalence.
Alternatively, when a broad spectrum of coal types will be tested, the instrument used in these test methods shall be calibrated using
certified reference materials of known composition covering the range of parameters being determined. The certified values shall
be established using Test Methods D3173, D3174, and D3175. Section 16.2 lists a number of biases that have been shown to exist
between instrumental results. Other biases, of unknown magnitude and sign, may exist for other coals.
5. Significance and Use
5.1 Moisture, as determined by this instrumental test method, is used for calculating other analytical results to a dry basis using
procedures in Practice D3180.
5.2 Moisture can be used in conjunction with the air-dry moisture loss determined by Test Method D3302 to determine total
moisture in coal. Total moisture is used for calculating other analytical results to an as-received basis using Practice D3180.
5.3 Ash yield is the residue remaining after heating the coal and coke samples (see Note 1).
Riley J.T., Yanes E.G, Marsh M., Lawrenz D., and Eichenbaum L., “Coal and Coke Volatile Matter Determination and Reconciliation of Differences in Yields Determined
by Two ASTM Methods,” J. Testing and Evaluation, 2010, 38(4), 458-466.
D7582 − 15 (2023)
NOTE 1—The ash obtained differs in composition and amount from the mineral constituents present in the original coal. Combustion causes an expulsion
of all water, the loss of carbon dioxide from carbonates, the conversion of iron pyrite into iron oxides and sulfur oxides, and other chemical reactions.
Ash yield, as determined by this test method, can differ from the amount of ash produced in furnace operations or other combustion systems because
combustion conditions influence the chemistry and amount of ash.
5.4 Ash yield is used, (1) as a parameter for evaluating sampling procedures and coal cleaning processes, (2) in the ultimate
analysis calculation of oxygen by difference using Practice D3176, (3) in calculations including material balance, reactivity and
yields of products relevant to coal conversion processes such as gasification and liquefaction, (4) in calculations to estimate the
loading on electrostatic precipitators and on the fly ash and bottom ash disposal systems as well as erosion rates on boiler systems.
5.5 Volatile matter yield, when determined as herein described, may be used to (1) indicate coke yield on carbonization, (2)
provide the basis for purchasing and selling, or (3) establish combustion characteristics.
5.6 Fixed carbon is a calculated value. It is the difference between 100 and the sum of the percent moisture, ash, and volatile
matter. All percents shall be on the same moisture reference base.
5.7 Moisture, ash, and volatile matter are three of the principal parameters used for assessing the quality of coal.
6. Interferences
6.1 There are no known interferences for these test methods.
7. Apparatus
7.1 Macro Thermogravimetric Analyzer (Macro TGA)—A computer controlled apparatus consisting of a furnace with a cavity
large enough to accept crucibles containing test specimens that meet the minimum mass requirements of the procedure. The macro
TGA system can accommodate multiple crucibles, allowing for continuous analysis with one crucible reserved for the blank or
reference crucible. The furnace is constructed so the cavity is surrounded by a suitable refractory and insulated so as to develop
a uniform temperature in all parts of the cavity, but with a minimum free space. The furnace shall be capable of being heated
rapidly (30-45°C/min(30 °C ⁄min to 45 °C ⁄min from ambient to 950°C.950 °C. The temperature shall be monitored and maintained
at values specified for each determination. The system shall have an integrated balance capable of weighing the crucibles and test
specimens repeatedly throughout the analysis. All mass measurements are conducted and recorded by the system. The sensitivity
of the balance shall be at least 0.1 mg. 0.1 mg. Provision shall be made to introduce gases specified for this standard and to remove
products of drying, devolatilization, and combustion. The macro TGA system shall have a venting fan, tolerant of hot product
gases, to efficiently remove the exhaust gases.
7.2 Crucibles—with covers of composition and dimensions specified for the instrument by the instrument manufacturer. The
covers shall fit closely enough so that the carbon deposit from bituminous, subbituminous, and lignitic coals does not burn away
from the underside of the cover during the determination of the volatile matter
8. Reagents and Materials
8.1 Drying Gas—Nitrogen (99.5%(99.5 % purity), Argon (99.5%(99.5 % purity) or air, dried to a moisture content of 1.9 mg/L
or less (dew point –10°C–10 °C or less).
8.2 Inert Gas—Nitrogen (99.5%(99.5 % purity) or Argon (99.5%(99.5 % purity).
8.3 Oxidizing Gas—Oxygen (99.5%(99.5 % purity) or air.
8.4 Certified Reference Materials—Coal or coke material(s) meeting the requirements of 10.1, with a certificate of analysis
specifying the reference value and the uncertainty of the reference value. Reference material(s) can be employed to calibrate the
instrument for the determination of volatile matter. Certified reference values shall have been established using Test Methods
D3173, D3174, and D3175. Reference materials used for the calibration of volatile matter shall include information on the
certificate of analysis detailing the method(s) employed to determine volatile matter of the reference material.
D7582 − 15 (2023)
9. Hazards
9.1 The user shall insure acceptable documented safety procedures are in place for the handling of all reagents and test materials
and for the operation of laboratory equipment specified for these test methods.
9.2 Venting Equipment—Install equipment in the vicinity of the apparatus to vent combustion and volatile gases evolved during
the test procedures from the laboratory.
10. Analysis Sample
10.1 The analysis sample shall be the material pulverized to pass a 250-μm (No. 60) sieve in accordance with Practice D2013 or
Practice D346.
11. Preparation of Apparatus
11.1 Verify the instrument can meet all specifications in the standard with respect to gas flows, heating rates, and balance
sensitivity prior to use. Condition the instrument after initial setup, or repairs, by conducting a run through a complete cycle
without samples.
11.2 Condition new crucibles and covers for use in these test methods by heating under the same conditions of the test and cool
before use.
11.3 The macro TGA system can be programmed to terminate the measurement process when the test specimens and crucibles
have reached a constant mass. Crucibles are weighed by the instrument at specified intervals. The analysis is complete when the
sample reaches constant mass. Constant mass is defined as a point where the mass change is < or = to 0.05%0.05 % over a
nine-minute period, either by using not less than three successive weighings or a fixed nine-minute period of successive weighings.
This mass change of 0.05%0.05 % is equivalent to 0.0005 g 0.0005 g for a 1.0000 g 1.0000 g sample. Alternately, the instrument
can be programmed to allow for moisture and ash determination by heating the test specimens for the time periods, heating rates
and soak temperatures specified in Test Methods D3173 and D3174. The mass measured at the end of the time period is used for
calculations.
12. Calibration and Standardization
12.1 The instrument shall be calibrated for the determination of volatile matter employing certified reference materials. The
calibration shall be performed at the same furnace ramp temperature as that used for the analysis. Do not use coal reference
material(s) for coke volatile matter calibration. Do not use coke reference material(s) for coal volatile matter calibration. Use coal
reference material(s) with a certified reference value and uncertainty based on measurements made employing Test Methods
D317
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.