ASTM E790-21

Standard Test Method for Residual Moisture in Refuse-Derived Fuel Analysis Samples

SIGNIFICANCE AND USE
5.1 The procedure in this test method for a sample as specified herein is intended for the purpose of determining the residual moisture present in a RDF analysis sample.  
5.2 The residual moisture value is used to correct as-determined analysis results such as gross heating value, sulfur, and ash to dry sample basis results.
SCOPE
1.1 This test method covers the measurement of residual moisture in refuse-derived fuel (RDF) analysis samples. It is used to calculate on a dry basis other determinations performed on analysis RDF samples. It is used with air-dry moisture results to calculate total moisture (Note 1). The total moisture is used to calculate as-received values or other analyses performed on a sample.  
Note 1: In some instances, RDF moisture may change during size-reduction steps of the RDF analysis sample preparation procedure. This moisture change, unless suitable corrections are made, will affect the accuracy of the total moisture value as calculated from the air-dry and residual moisture results.  
1.2 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. For more specific precautionary information, see Section 7.  
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: 30-Apr-2021
• ICS: 75.160.10 - Solid fuels
• Technical Committee: D34 - Waste Management
• Drafting Committee: D34.03 - Treatment, Recovery and Reuse

Relations

• Refers: ASTM D5681-23 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Nov-2023
• Refers: ASTM D5681-18 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Nov-2018
• Refers: ASTM D5681-17 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Sep-2017
• Refers: ASTM D5681-16a - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Nov-2016
• Refers: ASTM D5681-16 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Feb-2016
• Refers: ASTM D5681-13 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Feb-2013
• Refers: ASTM D3173-11 - Standard Test Method for Moisture in the Analysis Sample of Coal and Coke
• Effective Date: 01-Apr-2011
• Refers: ASTM D5681-09 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Jul-2009
• Refers: ASTM D6044-96(2009) - Standard Guide for Representative Sampling for Management of Waste and Contaminated Media
• Effective Date: 01-Feb-2009
• Refers: ASTM D5681-08 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Sep-2008
• Refers: ASTM D3173-03(2008) - Standard Test Method for Moisture in the Analysis Sample of Coal and Coke
• Effective Date: 01-Feb-2008
• Refers: ASTM D5681-98a(2004) - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Sep-2004
• Refers: ASTM D5681-98a(2004)e1 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Sep-2004
• Refers: ASTM D3173-03 - Standard Test Method for Moisture in the Analysis Sample of Coal and Coke
• Effective Date: 10-Apr-2003
• Refers: ASTM D6044-96(2003) - Standard Guide for Representative Sampling for Management of Waste and Contaminated Media
• Effective Date: 10-Mar-2003

Overview

ASTM E790-21: Standard Test Method for Residual Moisture in Refuse-Derived Fuel Analysis Samples is an internationally recognized methodology developed by ASTM International. This standard addresses the accurate measurement of residual moisture in refuse-derived fuel (RDF) analysis samples. Determining residual moisture content is fundamental for laboratories and industries that rely on precise calculations of RDF properties, such as gross heating value, sulfur content, and ash. These calculations allow for analysis on a dry sample basis, which enhances comparability and reliability between samples and facilities.

The standard is crucial for ensuring consistent and repeatable results in RDF testing, supporting waste management, fuel production, and regulatory compliance efforts worldwide.

Key Topics

• Residual Moisture Measurement: Outlines a repeatable process for quantifying residual moisture present in RDF analysis samples. Accurate measurement is vital to calculate other material parameters on a dry basis.
• Drying Procedures: Details controlled oven-drying requirements, including temperature, air flow, and timing, to ensure accurate and consistent results.
• Sample Preparation: Emphasizes the importance of representative sampling, particle size reduction, and proper sample storage to minimize moisture changes before testing.
• Impacts on Analysis: Clarifies how residual moisture values are used to correct analysis results, such as heating value, sulfur, and ash, shifting them to a dry matter reference.
• Moisture Calculations: Provides formulas for calculating both residual and total moisture, which combines air-dry and oven-dried moisture losses.
• Precision Requirements: Specifies standard deviations for results within and between laboratories, ensuring data integrity and repeatability.
• Safety and Handling: Recommends safety procedures when dealing with RDF, which may contain hazardous materials.

Applications

ASTM E790-21 is applied extensively in:

• Waste-to-Energy Facilities: These operators use the standard to assess RDF quality and energy content, critical for optimizing combustion efficiency and regulatory reporting.
• Environmental Testing Laboratories: Laboratories leverage this test method for routine RDF analysis, ensuring that results are comparable across projects and jurisdictions.
• Regulatory Compliance: Government and industry regulators reference this standard to verify that fuel characteristics meet environmental and performance benchmarks.
• Research and Development: Researchers involved in alternative fuels and municipal waste management use the method to evaluate changes in RDF moisture under various processing conditions.
• Fuel Specification Adjustments: Calculating total moisture content allows energy providers to convert “as-received” results to dry basis, supporting procurement and quality control decisions.

By standardizing the approach to residual moisture analysis, ASTM E790-21 enables stakeholders to make informed decisions regarding fuel handling, storage, and utilization.

Related Standards

Understanding ASTM E790-21 in context often involves reference to other key ASTM documents:

• ASTM D3173: Test Method for Moisture in the Analysis Sample of Coal and Coke - referenced for similar drying oven procedures.
• ASTM D5681: Terminology for Waste and Waste Management - provides definitions and consistent language.
• ASTM D6044: Guide for Representative Sampling for Waste and Contaminated Media - offers sampling protocols to ensure accurate laboratory testing.
• ASTM E829: Practice for Preparing RDF Laboratory Samples for Analysis - used alongside E790-21 to ensure sample suitability.
• ASTM E180: Practice for Determining Precision of ASTM Methods for Industrial Chemicals (withdrawn 2009) - informs precision estimates for moisture analysis.

By adopting ASTM E790-21 and its referenced standards, organizations uphold high-quality practices in fuel characterization and waste management, promoting reliable, comparable, and actionable data across the sector.

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: E790 − 21
Standard Test Method for
Residual Moisture in Refuse-Derived Fuel Analysis
Samples
This standard is issued under the fixed designation E790; 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 D5681 Terminology for Waste and Waste Management
D6044 Guide for Representative Sampling for Management
1.1 This test method covers the measurement of residual
of Waste and Contaminated Media
moisture in refuse-derived fuel (RDF) analysis samples. It is
E180 Practice for Determining the Precision of ASTM
usedtocalculateonadrybasisotherdeterminationsperformed
Methods for Analysis and Testing of Industrial and Spe-
on analysis RDF samples. It is used with air-dry moisture
cialty Chemicals (Withdrawn 2009)
results to calculate total moisture (Note 1). The total moisture
E829 Practice for Preparing Refuse-Derived Fuel (RDF)
is used to calculate as-received values or other analyses
Laboratory Samples for Analysis
performed on a sample.
NOTE 1—In some instances, RDF moisture may change during size-
3. Terminology
reduction steps of the RDF analysis sample preparation procedure. This
3.1 For definitions of terms used in this test method, refer to
moisture change, unless suitable corrections are made, will affect the
accuracy of the total moisture value as calculated from the air-dry and
Terminology D5681.
residual moisture results.
4. Summary of Test Method
1.2 The values stated in SI units are to be regarded as
standard. No other units of measurement are included in this
4.1 This test method is based on the weight loss of an
standard.
air-dried analysis RDF sample under rigidly controlled condi-
1.3 This standard does not purport to address all of the tions of temperature, time, and air flow.
safety concerns, if any, associated with its use. It is the
4.2 The total moisture is calculated from the loss or gain
responsibility of the user of this standard to establish appro-
uponsampleairdryingandtheresidualmoistureasdetermined
priate safety, health, and environmental practices and deter-
by this test method.
mine the applicability of regulatory limitations prior to use.
For more specific precautionary information, see Section 7.
5. Significance and Use
1.4 This international standard was developed in accor-
5.1 The procedure in this test method for a sample as
dance with internationally recognized principles on standard-
specified herein is intended for the purpose of determining the
ization established in the Decision on Principles for the
residual moisture present in a RDF analysis sample.
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
5.2 The residual moisture value is used to correct as-
Barriers to Trade (TBT) Committee. determined analysis results such as gross heating value, sulfur,
and ash to dry sample basis results.
2. Referenced Documents
2.1 ASTM Standards: 6. Apparatus
D3173 Test Method for Moisture in the Analysis Sample of
6.1 Drying Oven:
Coal and Coke
6.1.1 RefereeType—The oven shall be constructed to have a
uniform temperature within the specimen chamber, have a
This test method is under the jurisdiction of ASTM Committee D34 on Waste
minimum excess air volume, and be capable of constant
Management and is the direct responsibility of Subcommittee D34.03 on Treatment,
temperature regulation at 107 6 3 °C. Provision shall be made
Recovery and Reuse.
for renewing the preheated air in the oven at the rate of two to
Current edition approved May 1, 2021. Published May 2021. Originally
approved in 1981. Last previous edition approved in 2015 as E790 – 15. DOI: four times the oven air volume a minute, with the intake air
10.1520/E0790-21.
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 last approved version of this historical standard is referenced on
the ASTM website. www.astm.org.
Copyright ©ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA19428-2959. United States
E790 − 21
dried by passing through a desiccant. An oven similar to the 8.2 The sampling method used to collect samples for this
one illustrated in Fig. 1 of Test Method D3173 is suitable. procedure should be based on agreement between the involved
parties.
6.1.2 Routine Type—Adrying oven of either the mechanical
ornaturalcirculationtypewhichiscapableofconstantuniform
8.3 Thelaboratorysamplemustbeairdriedandparticlesize
temperature within the specimen chamber regulated at 107 6
reduced to pass through a 0.5-mm screen for this analysis.This
3 °C.
procedure must be performed carefully to preserve the sam-
ple’s representativeness beyond just particle size while prepar-
NOTE 2—Either type of oven may be used for routine determinations.
ing the analysis sample to be analyzed according to this
However, the referee-type oven shall be used to resolve differences
between determinations. procedure. For additional guidance on preparing RDF samples
for laboratory analysis, see Practice E829.
6.2 Containers—Sample ash determinations are made using
a porcelain capsule 22 mm in depth and 44 mm in diameter or
9. Procedure
a fused silica capsule of similar shape. A we
...

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: E790 − 15 E790 − 21
Standard Test Method for
Residual Moisture in Refuse-Derived Fuel Analysis
Samples
This standard is issued under the fixed designation E790; 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 measurement of residual moisture in refuse-derived fuel (RDF) analysis samples. It is used to
calculate on a dry basis other determinations performed on analysis RDF samples. It is used with air-dry moisture results to
calculate total moisture (Note 1). The total moisture is used to calculate as-received values or other analyses performed on a
sample.
NOTE 1—In some instances, RDF moisture may change during size-reduction steps of the RDF analysis sample preparation procedure. This moisture
change, unless suitable corrections are made, will affect the accuracy of the total moisture value as calculated from the air-dry and residual moisture
results.
1.2 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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use. For more specific precautionary information, see Section 7.
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:
D3173 Test Method for Moisture in the Analysis Sample of Coal and Coke
D5681 Terminology for Waste and Waste Management
D6044 Guide for Representative Sampling for Management of Waste and Contaminated Media
E180 Practice for Determining the Precision of ASTM Methods for Analysis and Testing of Industrial and Specialty Chemicals
(Withdrawn 2009)
E829 Practice for Preparing Refuse-Derived Fuel (RDF) Laboratory Samples for Analysis
3. Terminology
3.1 For definitions of terms used in this test method, refer to Terminology D5681.
This test method is under the jurisdiction of ASTM Committee D34 on Waste Management and is the direct responsibility of Subcommittee D34.03 on Treatment,
Recovery and Reuse.
Current edition approved Sept. 1, 2015May 1, 2021. Published September 2015May 2021. Originally approved in 1981. Last previous edition approved in 20082015 as
E790 – 08.E790 – 15. DOI: 10.1520/E0790-15.10.1520/E0790-21.
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.
The last approved version of this historical standard is referenced on www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E790 − 21
4. Summary of Test Method
4.1 This test method is based on the weight loss of an air-dried analysis RDF sample under rigidly controlled conditions of
temperature, time, and air flow.
4.2 The total moisture is calculated from the loss or gain upon sample air drying and the residual moisture as determined by this
test method.
5. Significance and Use
5.1 The procedure in this test method for a sample as specified herein is intended for the purpose of determining the residual
moisture present in a RDF analysis sample.
5.2 The residual moisture value is used to correct as-determined analysis results such as gross heating value, sulfur, and ash to
dry sample basis results.
6. Apparatus
6.1 Drying Oven:
6.1.1 Referee Type—The oven shall be constructed to have a uniform temperature within the specimen chamber, have a minimum
excess air volume, and be capable of constant temperature regulation at 107 6 3°C.3 °C. Provision shall be made for renewing
the preheated air in the oven at the rate of two to four times the oven air volume a minute, with the intake air dried by passing
through a desiccant. An oven similar to the one illustrated in Fig. 1 of Test Method D3173 is suitable.
6.1.2 Routine Type—A drying oven of either the mechanical or natural circulation type which is capable of constant uniform
temperature within the specimen chamber regulated at 107 6 3°C.3 °C.
NOTE 2—Either type of oven may be used for routine determinations. However, the referee-type oven shall be used to resolve differences between
determinations.
6.2 Containers—Sample ash determinations are made using a porcelain capsule 22 mm in depth and 44 mm in diameter or a fused
silica capsule of similar shape. A well-fitting flat aluminum cover is used when ashing samples. Platinum crucibles or glass
capsules with ground-glass caps may also be used. They should be as shallow as possible while remaining convenient to handle.
6.3 Analytical Balance—Balance capable of weighing with an accuracy of 0.1 mg.
6.4 Analysis Sample Containers—Heavy (minimum 4 mil), vapor-impervious bags, properly sealed; or noncorroding cans, glass
jars, or plastic bottles with air-tightairtight sealing covers to store RDF samples for analysis. Containers shall be checked for
suitability by measuring weight loss or gain of the sample and container stored for 1one week under ambient laboratory conditions.
The weight loss or gain should be less than 0.5 % of the sample weight stored in the container.
7.
...