ASTM D4931-23

Standard Test Method for Gross Moisture in Green Petroleum Coke

SIGNIFICANCE AND USE
5.1 Moisture adds mass to the coke and serves no useful purpose. A knowledge of the moisture content is important in the purchase and sale of green petroleum coke, both of which are conducted on a dry basis.  
5.2 The collection of the sample as specified for the Drying Oven Method is intended for the express purpose of determining the total moisture of green petroleum coke. The standard is available to producers, sellers, and consumers for determination when other techniques or modifications are not mutually agreed on.  
5.3 The Preparation Procedure is used only when sample contains free water. Obtaining a representative sample of a coke source is compounded by the presence of free water.
SCOPE
1.1 This test method covers both the preparation procedure for samples containing free water (air drying loss (ADL) on gross moisture samples) and the determination of the gross moisture content of green petroleum coke.  
1.2 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered 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: 31-Oct-2023
• ICS: 73.040 - Coals
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.05 - Properties of Fuels, Petroleum Coke and Carbon Material

Relations

• Replaces: ASTM D4931-06(2017) - Standard Test Method for Gross Moisture in Green Petroleum Coke
• Effective Date: 01-Nov-2023
• Refers: ASTM D121-15(2024) - Standard Terminology of Coal and Coke
• Effective Date: 01-Mar-2024
• Refers: ASTM D4175-23a - Standard Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants
• Effective Date: 15-Dec-2023
• Refers: ASTM D4175-23e1 - Standard Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants
• Effective Date: 01-Jul-2023
• Refers: ASTM D121-15 - Standard Terminology of Coal and Coke
• Effective Date: 01-Sep-2015
• Referred By: ASTM D6969-23 - Standard Practice for Preparation of Calcined Petroleum Coke Samples for Analysis
• Effective Date: 01-Nov-2023

Overview

ASTM D4931-23, Standard Test Method for Gross Moisture in Green Petroleum Coke, establishes a comprehensive and standardized method for determining the gross moisture content-including both residual moisture and free water-of green petroleum coke. Precise measurement of moisture is critical as it impacts the mass and quality of green petroleum coke, which is often traded and evaluated on a dry-mass basis. This standard is essential for producers, consumers, and sellers to ensure consistency and reliability in the purchase and sale of green petroleum coke.

Key Topics

• Gross Moisture Determination: Defines procedures for measuring the total moisture present in green petroleum coke, incorporating both air drying and oven drying methods.
• Sample Preparation: Specifies steps for preparing and processing samples, particularly when free water is present, to obtain accurate and representative results.
• Moisture Calculation: Describes calculations for air drying loss (ADL), residual moisture, and total moisture percentage.
• Reproducibility and Repeatability: Provides established repeatability (0.34%) and reproducibility (0.58%) values, ensuring reliable and consistent results across laboratories.
• Equipment and Apparatus: Details requirements for ovens, drying pans, balances, and sample containers to maintain testing accuracy.
• Safety and Compliance: Advises users to establish appropriate safety, health, environmental practices, and regulatory compliance for laboratory operations.

Applications

ASTM D4931-23 serves several practical applications within the petroleum industry and related sectors:

• Commercial Transactions: Ensures accurate determination of moisture content for purchase and sale of green petroleum coke, allowing parties to transact based on dry mass, thereby avoiding disputes over product weight inflated by moisture.
• Process Control: Assists coke producers in monitoring and controlling the moisture content during processing, improving product quality and operational efficiency.
• Quality Assurance: Provides a reliable reference for quality control laboratories and inspection agencies to verify the moisture characteristics of green petroleum coke batches.
• Material Handling: Facilitates appropriate handling and storage procedures by identifying the level of free water in the material, which can impact transportation, storage, and safety.

Related Standards

For thorough understanding and correct application of ASTM D4931-23, refer to these related ASTM standards:

• ASTM D121: Terminology of Coal and Coke-Defines essential terms used in coke and coal testing.
• ASTM D2013: Practice for Preparing Coal Samples for Analysis-Outlines sample preparation steps relevant to coke testing.
• ASTM D2234/D2234M: Practice for Collection of a Gross Sample of Coal-Guides proper sample collection methods, applied here to green petroleum coke.
• ASTM D3302: Test Method for Total Moisture in Coal-Prescribes controlled drying conditions relevant to residual moisture measurement.
• ASTM D4175: Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants-Provides definitions for petroleum and lubricant testing.
• ASTM E11: Specification for Woven Wire Test Sieve Cloth and Test Sieves-Specifies requirements for sieves used in particle size reduction and sample division.

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By adhering to ASTM D4931-23, stakeholders within the petroleum coke supply chain can ensure precise gross moisture determination, enabling fair commerce, consistent processing, and robust quality control. Utilizing this standardized method supports operational transparency and reduces variability, aligning with global best practices in petroleum laboratory analysis.

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: D4931 − 23
Standard Test Method for
Gross Moisture in Green Petroleum Coke
This standard is issued under the fixed designation D4931; 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* 3.1.1 For definitions of terms used in this test method, refer
to Terminologies D121 and D4175.
1.1 This test method covers both the preparation procedure
3.2 Definitions of Terms Specific to This Standard:
for samples containing free water (air drying loss (ADL) on
3.2.1 air drying, n—a process of partial drying of a green
gross moisture samples) and the determination of the gross
petroleum coke sample to bring it to near equilibrium with the
moisture content of green petroleum coke.
atmosphere in the room in which further reduction/division of
1.2 Units—The values stated in SI units are to be regarded
the petroleum coke sample is to take place.
as standard. The values given in parentheses after SI units are
3.2.2 air dry loss, ADL, n—the loss in mass, expressed as a
provided for information only and are not considered standard.
percentage, resulting from each air drying operation.
1.3 This standard does not purport to address all of the
3.2.3 free water, n—visible unbound water in the sample.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
3.2.4 green petroleum coke, n—same as raw petroleum
priate safety, health, and environmental practices and deter-
coke.
mine the applicability of regulatory limitations prior to use.
3.2.5 gross moisture, n—that moisture determined as the
1.4 This international standard was developed in accor-
loss in mass in an air atmosphere under rigidly controlled
dance with internationally recognized principles on standard-
conditions of temperature, time, and air flow.
ization established in the Decision on Principles for the
3.2.5.1 Discussion—Test Method D3302 prescribes the
Development of International Standards, Guides and Recom-
above controlled conditions.
mendations issued by the World Trade Organization Technical
3.2.6 petroleum coke, n—solid, carbonaceous residue pro-
Barriers to Trade (TBT) Committee.
duced by thermal decomposition of heavy petroleum fractions,
2. Referenced Documents
or cracked stocks, or both.
2.1 ASTM Standards:
3.2.7 residual moisture, n—that moisture remaining in the
D121 Terminology of Coal and Coke
sample after air drying.
D2013 Practice for Preparing Coal Samples for Analysis
3.2.8 total moisture, n—synonym for gross moisture.
D2234/D2234M Practice for Collection of a Gross Sample
of Coal
4. Summary of Test Method
D3302 Test Method for Total Moisture in Coal
D4175 Terminology Relating to Petroleum Products, Liquid
4.1 This test method is based on the loss in mass of a green
Fuels, and Lubricants
petroleum coke sample in an air atmosphere under controlled
E11 Specification for Woven Wire Test Sieve Cloth and Test
conditions of temperature, time, and air flow.
Sieves
4.1.1 Preparation Procedure shall be used when the petro-
leum coke sample contains free water. The gross moisture
3. Terminology
sample mass is determined and air dried to equilibrate it with
3.1 Definitions:
the atmosphere. Determination of residual moisture is deter-
mined using the Drying Oven Method. Air drying and residual
This test method is under the jurisdiction of ASTM Committee D02 on moisture losses are combined to report gross moisture.
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of
4.1.2 Drying Oven Method shall be used in routine com-
Subcommittee D02.05 on Properties of Fuels, Petroleum Coke and Carbon Material.
mercial practice when the sample does not contain free water.
Current edition approved Nov. 1, 2023. Published November 2023. Originally
The sample is crushed to at least minus 25 mm (1 in.) top sieve
approved in 1989. Last previous edition approved in 2017 as D4931 – 06 (2017).
DOI: 10.1520/D4931-23.
size and divided into analytical portions of at least 500 g each.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Determination of total gross moisture is calculated by summing
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
the results of the Drying Oven Method and the results of the
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. Preparation Procedure.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D4931 − 23
5. Significance and Use
5.1 Moisture adds mass to the coke and serves no useful
purpose. A knowledge of the moisture content is important in
the purchase and sale of green petroleum coke, both of which
are conducted on a dry basis.
5.2 The collection of the sample as specified for the Drying
Oven Method is intended for the express purpose of determin-
ing the total moisture of green petroleum coke. The standard is
available to producers, sellers, and consumers for determina-
tion when other techniques or modifications are not mutually
agreed on.
5.3 The Preparation Procedure is used only when sample
contains free water. Obtaining a representative sample of a
coke source is compounded by the presence of free water.
6. Apparatus
6.1 Ovens:
6.1.1 Air Drying Oven—A device for passing slightly heated
air over the sample. The oven shall be capable of maintaining
a temperature of 10 °C to 15 °C (18 °F to 27 °F) above ambient
with a maximum oven temperature of 40 °C (104 °F) unless
ambient temperature is above 40 °C (104 °F), in which case
ambient temperature shall be used. Air changes are to be at the
rate of 1 to 4/min. A typical oven is shown in Fig. 1.
6.1.2 Drying Oven (for residual moisture on minus 25 mm
(1.0 in.) samples sieve USA standard—forced-air type). It shall
be capable of maintaining a temperature of 105 °C 6 5 °C and
so constructed that fresh air is introduced to all parts of the
oven to ensure the removal of moisture-laden air. Air flow shall
be maintained at sufficiently low velocity to prevent loss of fine
particles, (for example, one exchange per minute).
6.2 Drying Pans:
6.2.1 Pans for the gross moisture sample (Preparation
FIG. 1 Air Drying Oven
Procedure) shall be noncorroding, mass-stable at temperature
used, and large enough so that the sample can be spread to a
6.5 Sieves—Meeting Specification E11.
depth of not more than twice the diameter of the largest
particles, or not more than 25 mm (1.0 in.) depth for smaller
7. Sampling
coke. The pan sides shall be 50 mm to 75 mm (2 in. to 3 in.)
7.1 The principles, terms, and procedures as set forth in
high.
Practice D2234/D2234M shall apply to the collection of the
6.2.2 Pans for crushed and divided sample shall be
total moisture sample. Particular attention is directed to the
noncorroding, mass-stable at temperature used, and large
section on Sampling Coal for Total Gross Moisture Determi-
enough so that the sample can be spread to depth of not more
nation.
than 50 mm (2 in.). The sides shall be not more than 75 mm
7.2 Proceed with determination of moisture without unnec-
(3 in.) high.
essary delay to minimize the loss (or gain) of moisture to air or
6.3 Balances:
the walls of the sample container. Visible condensation on the
6.3.1 Balance (Gross Sample)—A balance with a minimum
walls of the sample container indicates a moisture loss by the
capacity of 10 kg and sensitive to 1 g.
sample. Determine the moisture on the gross sample and
6.3.2 Balance (Crushed Sample)—A balance with a mini-
include the sample container in the drying process adding the
mum capacity of 4 kg or sufficient to determine the mass of the
mass loss of the container to G (mass of sampl
...

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: D4931 − 06 (Reapproved 2017) D4931 − 23
Standard Test Method for
Gross Moisture in Green Petroleum Coke
This standard is issued under the fixed designation D4931; 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 Scope*
1.1 This test method covers both the preparation procedure for samples containing free water (air drying loss (ADL) on gross
moisture samples) and the determination of the gross moisture content of green petroleum coke.
1.2 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided
for information only and are not considered standard.
1.2.1 Exception—The values given in parentheses are for information only.
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
2.1 ASTM Standards:
D121 Terminology of Coal and Coke
D2013 Practice for Preparing Coal Samples for Analysis
D2234/D2234M Practice for Collection of a Gross Sample of Coal
D3302 Test Method for Total Moisture in Coal
D4175 Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants
E11 Specification for Woven Wire Test Sieve Cloth and Test Sieves
3. Terminology
3.1 Definitions:
3.1.1 For definitions of terms used in this test method, refer to Terminologies D121 and D4175.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 air drying, n—a process of partial drying of a green petroleum coke sample to bring it to near equilibrium with the
atmosphere in the room in which further reduction/division of the petroleum coke sample is to take place.
This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of Subcommittee
D02.05 on Properties of Fuels, Petroleum Coke and Carbon Material.
Current edition approved Oct. 1, 2017Nov. 1, 2023. Published November 2017November 2023. Originally approved in 1989. Last previous edition approved in 20112017
as D4931 – 06 (2011).(2017). DOI: 10.1520/D4931-06R17.10.1520/D4931-23.
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.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D4931 − 23
3.2.2 air dry loss, ADL, n—the loss in mass, expressed as a percentage, resulting from each air drying operation.
3.2.3 free water, n—visible unbound water in the sample.
3.2.4 green petroleum coke, n—same as raw petroleum coke.
3.2.5 gross moisture, n—that moisture determined as the loss in mass in an air atmosphere under rigidly controlled conditions of
temperature, time, and air flow.
3.2.5.1 Discussion—
Test Method D3302 prescribes the above controlled conditions.
3.2.6 petroleum coke, n—solid, carbonaceous residue produced by thermal decomposition of heavy petroleum fractions, or
cracked stocks, or both.
3.2.7 residual moisture, n—that moisture remaining in the sample after air drying.
3.2.8 total moisture, n—synonym for gross moisture.
4. Summary of Test Method
4.1 This test method is based on the loss in mass of a green petroleum coke sample in an air atmosphere under controlled
conditions of temperature, time, and air flow.
4.1.1 Preparation Procedure shall be used when the petroleum coke sample contains free water. The gross moisture sample mass
is weigheddetermined and air dried to equilibrate it with the atmosphere. Determination of residual moisture is that determined
using the Drying Oven Method. Air drying and residual moisture losses are combined to report gross moisture.
4.1.2 Drying Oven Method shall be used in routine commercial practice when the sample does not contain free water. The sample
is crushed to at least minus 25 mm (1 in.) top sieve size and divided into analytical portions of at least 500 g each. Determination
of total gross moisture is calculated by summing the results of the Drying Oven Method and the results of the Preparation
Procedure.
5. Significance and Use
5.1 Moisture adds mass to the coke and serves no useful purpose. A knowledge of the moisture content is important in the purchase
and sale of green petroleum coke, both of which are conducted on a dry basis.
5.2 The collection of the sample as specified for the Drying Oven Method is intended for the express purpose of determining the
total moisture of green petroleum coke. The standard is available to producers, sellers, and consumers for determination when other
techniques or modifications are not mutually agreed on.
5.3 The Preparation Procedure is used only when sample contains free water. Obtaining a representative sample of a coke source
is compounded by the presence of free water.
6. Apparatus
6.1 Ovens:
6.1.1 Air Drying Oven—A device for passing slightly heated air over the sample. The oven shall be capable of maintaining a
temperature of 10 °C to 15 °C (18 °F to 27 °F) above ambient with a maximum oven temperature of 40 °C (104 °F) unless ambient
temperature is above 40 °C (104 °F), in which case ambient temperature shall be used. Air changes are to be at the rate of 1 to
4/min. A typical oven is shown in Fig. 1.
6.1.2 Drying Oven (for residual moisture on minus 25 mm (1.0 in.) samples sieve USA standard—forced-air type). It shall be
D4931 − 23
FIG. 1 Air Drying Oven
capable of maintaining a temperature of 105 °C 6 5 °C and so constructed that fresh air is introduced to all parts of the oven to
ensure the removal of moisture-laden air. Air flow shall be maintained at sufficiently low velocity to prevent loss of fine particles,
(for example, one exchange per minute).
6.2 Drying Pans:
6.2.1 Pans for the gross moisture sample (Preparation Procedure) shall be noncorroding, mass-stable at temperature used, and
large enough so that the sample can be spread to a depth of not more than twice the diameter of the largest particles, or not more
than 25 mm (1.0 in.) depth for smaller coke. The pan sides shall be 50 mm to 75 mm (2 in. to 3 in.) high.
6.2.2 Pans for crushed and divided sample shall be noncorroding, mass-stable at temperature used, and large enough so that the
sample can be spread to depth of not more than 50 mm (2 in.). The sides shall be not more than 75 mm (3 in.) high.
6.3 Balances:
6.3.1 Balance (Gross Sample)—A balance with a minimum capacity of 10 kg and sensitive to 1 g.
6.3.2 Balance (Crushed Sample)—A balance with a minimum capacity of 44 kg or sufficient to weigh the determine the mass of
the pan, sample, and container and sensitive to with a resolution of 0.1 g.
6.4 Laboratory Sample Containers—Noncorroding cans with airtight, friction top or screw top sealed with a rubber gasket and
D4931 − 23
pressure-sensitive tape for use in storage and transport of the laboratory sample. Glass containers, sealed with rubber gaskets, can
be used, but care must be taken to avoid breakage in transport.
6.5 Sieves—Meeting Specification E11.
7. Sampling
7.1 The principles, terms, and procedures as set forth in Practice D2234/D2234M shall apply to the collection of the total moisture
sample. Particular attention is directed to the section on Sampling Coal for Total Gross Moisture Determination.
7.2 Proceed with determination of moisture without un
...