ASTM D2798-21

Standard Test Method for Microscopical Determination of the Vitrinite Reflectance of Coal

SIGNIFICANCE AND USE
5.1 The mean maximum reflectance of the vitrinite component in coal as determined by this test method is often used as an indicator of rank as presented in Classification D388, independent of petrographic composition, and in the characterization of coal as feedstock for carbonization, gasification, liquefaction, and combustion processes.  
5.2 This test method is for use in scientific and industrial research.
SCOPE
1.1 This test method covers the microscopical determination of both the mean maximum and mean random reflectances measured in oil of polished surfaces of vitrinite and other macerals present in coals ranging in rank from lignite to anthracite. This test method can be used to determine the reflectance of other macerals.  
1.2 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 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.  
1.4 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

• Status: Published
• Publication Date: 14-May-2021
• ICS: 71.060.10 - Chemical elements
• Technical Committee: D05 - Coal and Coke
• Drafting Committee: D05.28 - Petrographic Analysis of Coal and Coke

Relations

• Refers: ASTM D2797/D2797M-20 - Standard Practice for Preparing Coal Samples for Microscopical Analysis by Reflected Light
• Effective Date: 01-Feb-2020

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:D2798 −21
Standard Test Method for
Microscopical Determination of the Vitrinite Reflectance of
1
Coal
This standard is issued under the fixed designation D2798; 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 3.2 Abbreviations:
3.2.1 R max—mean maximum reflectance measured in oil.
o
1.1 Thistestmethodcoversthemicroscopicaldetermination
3.2.2 R ran—mean random reflectance measured in oil.
of both the mean maximum and mean random reflectances
o
3.2.2.1 Discussion—Other organizations may use other ab-
measured in oil of polished surfaces of vitrinite and other
breviations for mean maximum and mean random reflectance.
macerals present in coals ranging in rank from lignite to
anthracite. This test method can be used to determine the
4. Summary of Test Method
reflectance of other macerals.
4.1 Thereflectanceofthemaceralvitriniteorothermacerals
1.2 Units—The values stated in SI units are to be regarded
is determined in this test method by illuminating a polished
as standard. No other units of measurement are included in this
surface of a section of coal in immersion oil using a micro-
standard.
scopic system that photometrically measures the amount of
1.3 This standard does not purport to address all of the
light reflected from the surface. The reflected light is recorded
safety concerns, if any, associated with its use. It is the
in percent reflectance after calibration of photometric equip-
responsibility of the user of this standard to establish appro-
ment by measuring the reflected light from standards of
priate safety, health, and environmental practices and deter-
reflectance as calculated from their refractive indices.
mine the applicability of regulatory limitations prior to use.
1.4 This international standard was developed in accor-
5. Significance and Use
dance with internationally recognized principles on standard-
5.1 The mean maximum reflectance of the vitrinite compo-
ization established in the Decision on Principles for the
nent in coal as determined by this test method is often used as
Development of International Standards, Guides and Recom-
an indicator of rank as presented in Classification D388,
mendations issued by the World Trade Organization Technical
independent of petrographic composition, and in the charac-
Barriers to Trade (TBT) Committee.
terization of coal as feedstock for carbonization, gasification,
liquefaction, and combustion processes.
2. Referenced Documents
2
5.2 This test method is for use in scientific and industrial
2.1 ASTM Standards:
research.
D121 Terminology of Coal and Coke
D388 Classification of Coals by Rank
6. Apparatus
D2797/D2797M Practice for Preparing Coal Samples for
6.1 Microscope—Any microscope equipped for reflected
Microscopical Analysis by Reflected Light
light microscopy (such as a metallurgical or opaque-ore mi-
3. Terminology croscope) can be used, provided the lens combination of
objective and eyepieces permits examination of the specimen
3.1 Definitions—For definitions of terms, refer to Terminol-
at a magnification between 400x and 750x, such that particles
ogy D121.
of 1 µm can be resolved.The objectives shall be constructed so
that samples can be examined in oil with plane-polarized light
1
This test method is under the jurisdiction of ASTM Committee D05 on Coal
and have the highest quality of antireflection coatings. The
and Coke and is the direct responsibility of Subcommittee D05.28 on Petrographic
microscope shall be able to project an image at similar
Analysis of Coal and Coke.
magnification to a photomultiplier tube and to support the
Current edition approved May 15, 2021. Published June 2021. Originally
photomultiplier tube housing. Means shall be provided to
approved in 1969. Last previous edition approved in 2020 as D2798 – 20. DOI:
10.1520/D2798-21.
position the tube housing laterally to obtain maximum re-
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
sponse. The microscope shall have a circular stage that is
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
capable of rotating a specimen through 360°. The mechanical
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. stage attached to the microscope stage shall enable the analyst
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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...

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: D2798 − 20 D2798 − 21
Standard Test Method for
Microscopical Determination of the Vitrinite Reflectance of
1
Coal
This standard is issued under the fixed designation D2798; 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 This test method covers the microscopical determination of both the mean maximum and mean random reflectances measured
in oil of polished surfaces of vitrinite and other macerals present in coals ranging in rank from lignite to anthracite. This test method
can be used to determine the reflectance of other macerals.
1.2 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this
standard.
1.3 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.
1.4 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
2.1 ASTM Standards:
D121 Terminology of Coal and Coke
D388 Classification of Coals by Rank
D2797/D2797M Practice for Preparing Coal Samples for Microscopical Analysis by Reflected Light
3. Terminology
3.1 Definitions—For definitions of terms, refer to Terminology D121.
3.2 Abbreviations:
3.2.1 R max—mean maximum reflectance measured in oil.
o
3.2.2 R ran—mean random reflectance measured in oil.
o
1
This test method is under the jurisdiction of ASTM Committee D05 on Coal and Coke and is the direct responsibility of Subcommittee D05.28 on Petrographic Analysis
of Coal and Coke.
Current edition approved Feb. 1, 2020May 15, 2021. Published March 2020June 2021. Originally approved in 1969. Last previous edition approved in 20192020 as
D2798 – 11aD2798 – 20.(2019). DOI: 10.1520/D2798-20.10.1520/D2798-21.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. 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
1

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D2798 − 21
3.2.2.1 Discussion—
Other organizations may use other abbreviations for mean maximum and mean random reflectance.
4. Summary of Test Method
4.1 The reflectance of the maceral vitrinite or other macerals is determined in this test method by illuminating a polished surface
of a section of coal in immersion oil using a microscopic system that photometrically measures the amount of light reflected from
the surface. The reflected light is recorded in percent reflectance after calibration of photometric equipment by measuring the
reflected light from standards of reflectance as calculated from their refractive indices.
5. Significance and Use
5.1 The mean maximum reflectance of the vitrinite component in coal as determined by this test method is often used as an
indicator of rank as presented in Classification D388, independent of petrographic composition, and in the characterization of coal
as feedstock for carbonization, gasification, liquefaction, and combustion processes.
5.2 This test method is for use in scientific and industrial research.
6. Apparatus
6.1 Microscope—Any microscope equipped for reflected light microscopy (such as a metallurgical or opaque-ore microscope) can
be used, provided the lens combination of objective and eyepieces permits examination of the specimen at a magnification between
400x and 750x, such that particles of 1 μm 1 μm can be resolved. The objectives shall be constructed so that samples can be
examined in oil with plane-polarized light and have the highest quality of antireflection coatings. The microscope shall be able to
project an image at similar magnification to a photomultiplier tube and to support the photomultiplier tube housing. Means shall
be provided to position the tu
...