ASTM E711-23e1

Standard Test Method for Gross Calorific Value of Refuse-Derived Fuel by the Bomb Calorimeter

SIGNIFICANCE AND USE
5.1 The calorific value, or heat of combustion, is a measure of the energy available from a fuel. Knowledge of this value is essential in assessing the commercial worth of the fuel and to provide the basis of contract between producer and user.
SCOPE
1.1 This test method covers the determination of the gross calorific value of a prepared analysis sample of solid forms of refuse-derived fuel (RDF) by the bomb calorimeter method.  
1.2 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. For specific cautionary and precautionary statements, see 6.9 and Section 8.  
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-Mar-2023
• ICS: 75.160.10 - Solid fuels
• Technical Committee: D34 - Waste Management
• Drafting Committee: D34.01 - Monitoring and Characterization

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 E1-13 - Standard Specification for ASTM Liquid-in-Glass Thermometers
• Effective Date: 01-May-2013
• Refers: ASTM D5681-13 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Feb-2013
• Refers: ASTM D5681-09 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Jul-2009
• Refers: ASTM E775-87(2008)e1 - Standard Test Methods for Total Sulfur in the Analysis Sample of Refuse-Derived Fuel
• Effective Date: 01-Sep-2008
• Refers: ASTM E790-08 - Standard Test Method for Residual Moisture in a Refuse-Derived Fuel Analysis Sample
• Effective Date: 01-Sep-2008
• Refers: ASTM D5681-08 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Sep-2008
• Refers: ASTM E1-07 - Standard Specification for ASTM Liquid-in-Glass Thermometers
• Effective Date: 01-Nov-2007
• Refers: ASTM D1193-06 - Standard Specification for Reagent Water
• Effective Date: 01-Mar-2006
• Refers: ASTM E1-05 - Standard Specification for ASTM Liquid-in-Glass Thermometers
• Effective Date: 01-Nov-2005
• Refers: ASTM D5681-98a(2004) - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Sep-2004

Overview

ASTM E711-23e1 – Standard Test Method for Gross Calorific Value of Refuse-Derived Fuel by the Bomb Calorimeter specifies a standardized procedure for determining the gross calorific value, or heat of combustion, of solid forms of refuse-derived fuel (RDF) using a bomb calorimeter. The calorific value provides a direct measurement of the energy available from a fuel, essential for evaluating its commercial worth and supporting contractual agreements between RDF producers and users. This ASTM standard is intended for consistent, accurate assessment across laboratories, using SI units as the primary measurement system and ensuring international compatibility through adherence to the World Trade Organization Technical Barriers to Trade (TBT) principles.

Key Topics

• Calorific Value Determination: The method describes the procedures for burning a weighed RDF sample in an oxygen bomb calorimeter, measuring the temperature change, and calculating the gross calorific value after applying the necessary corrections.
• Sample Preparation and Types: Applies to all solid forms of refuse-derived fuel, including shredded, powdered, or pelletized RDF, requiring representative sampling and appropriate particle size reduction for analysis.
• Equipment Requirements: Specifies the use of a bomb calorimeter, suitable crucibles, thermometers, and ignition circuits, as well as stringent requirements for calibration and performance to ensure consistent results.
• Precision and Safety: Stresses proper sample handling, apparatus calibration, and implementation of thorough safety, health, and environmental practices when handling and testing RDF materials.
• Terminology: Uses standardized terminology for calorific value, calorimeter system, gross and net calorific value, and sample types, referencing industry-accepted definitions.

Applications

• Energy Value Assessment: Used by RDF producers, waste-to-energy facilities, environmental analysts, and fuel purchasers to objectively determine the energy content of refuse-derived fuels, aiding in energy recovery project planning and operational optimization.
• Quality Control: Assists manufacturers and users in routine quality control of RDF, ensuring consistent fuel specifications for combustion and power generation processes.
• Contractual Agreements: Provides a recognized reference for establishing agreements between RDF suppliers and users, verifying fuel value and compliance with regulatory or commercial standards.
• Comparative Analysis: Enables comparison of RDF calorific value with other fuels, supporting decisions in fuel selection, process adjustment, and environmental management strategies.
• Regulatory Compliance: Supports compliance with national and international waste management and renewable energy regulations that require standardized reporting of fuel properties.

Related Standards

• ASTM E775: Test Methods for Total Sulfur in Refuse-Derived Fuel Analysis Sample – provides complementary sulfur content analysis, allowing for precise calorific value adjustments.
• ASTM E790: Test Method for Residual Moisture in Refuse-Derived Fuel Analysis Samples – relevant for determining the required moisture corrections in calorimetric measurement.
• ASTM E829: Practice for Preparing Refuse-Derived Fuel (RDF) Laboratory Samples for Analysis – outlines sampling and sample preparation, ensuring representativeness.
• ASTM D1193: Specification for Reagent Water – ensures water quality used in the test method.
• ASTM D5681: Terminology for Waste and Waste Management – provides definitions and terminology for consistent use within waste-derived fuel testing.

By following ASTM E711-23e1, laboratories, waste facilities, and fuel buyers can rely on a globally recognized, precise, and repeatable method for measuring the gross calorific value of refuse-derived fuel, fostering fair trade, energy efficiency, and regulatory compliance in waste-to-energy applications.

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.
´1
Designation: E711 − 23
Standard Test Method for
Gross Calorific Value of Refuse-Derived Fuel by the Bomb
Calorimeter
This standard is issued under the fixed designation E711; 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.
ε NOTE—Editorial corrections were made throughout in April 2023.
1. Scope cialty Chemicals (Withdrawn 2009)
E775 Test Methods for Total Sulfur in the Analysis Sample
1.1 This test method covers the determination of the gross
of Refuse-Derived Fuel
calorific value of a prepared analysis sample of solid forms of
E790 Test Method for Residual Moisture in Refuse-Derived
refuse-derived fuel (RDF) by the bomb calorimeter method.
Fuel Analysis Samples
1.2 The values stated in SI units are to be regarded as E829 Practice for Preparing Refuse-Derived Fuel (RDF)
standard. The values given in parentheses after SI units are
Laboratory Samples for Analysis
provided for information only and are not considered standard.
3. Terminology
1.3 This standard does not purport to address all of the
3.1 For definitions of general terms used in D34 Waste
safety concerns, if any, associated with its use. It is the
Management standards, refer to Terminology D5681.
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter- 3.2 Definitions of Terms Specific to This Standard:
mine the applicability of regulatory limitations prior to use.
3.2.1 calorific value—the heat of combustion of a unit
For specific cautionary and precautionary statements, see 6.9 quantity of a substance. It may be expressed in joules per gram
and Section 8.
(J/g), British thermal units per pound (Btu/lb), or calories per
gram (cal/g) when required.
1.4 This international standard was developed in accor-
3.2.1.1 Discussion—The unit equivalents are as follows:
dance with internationally recognized principles on standard-
1 Btu (International Table) = 1055.06 absolute joules
ization established in the Decision on Principles for the
1 Calorie (International Table) = 4.1868 absolute joules
Development of International Standards, Guides and Recom-
1 Btu/lb = 2.326 J/g
mendations issued by the World Trade Organization Technical
1.8 Btu/lb = 1.0 cal/g
Barriers to Trade (TBT) Committee.
3.2.2 calorimeter—describes the bomb, the vessel with
2. Referenced Documents
stirrer, and the water in which the bomb is immersed.
3.2.3 energy equivalent—the energy required to raise the
2.1 ASTM Standards:
temperature (see 3.2.3.1) of the calorimeter system 1 °C (or
D1193 Specification for Reagent Water
1 °F) per gram of sample. This is the number that is multiplied
D5681 Terminology for Waste and Waste Management
by the corrected temperature rise in degrees and divided by the
E1 Specification for ASTM Liquid-in-Glass Thermometers
sample weight in grams to give the gross calorific value after
E180 Practice for Determining the Precision of ASTM
thermochemical corrections have been applied.
Methods for Analysis and Testing of Industrial and Spe-
3.2.3.1 Discussion—Temperature change is measured in
thermal units. Temperature changes may also be recorded in
electromotive force, ohms, or other units when other types of
This test method is under the jurisdiction of ASTM Committee D34 on Waste
temperature sensors are used. Consistent units must be used in
Management and is the direct responsibility of Subcommittee D34.01 on Monitor-
ing and Characterization. both the standardization and actual calorific determination.
Current edition approved April 1, 2023. Published April 2023. Originally
Time is expressed in minutes. Weights are measured in grams.
approved in 1987. Last previous edition approved in 2004 as E711 – 87 (2004),
3.2.4 gross calorific value—the heat produced by combus-
which was withdrawn July 2011 and reinstated in April 2023. DOI: 10.1520/E0711-
23E01.
tion of a unit quantity of solid fuel, at constant volume, in an
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, PA 19428-2959. United States
´1
E711 − 23
oxygen bomb calorimeter under specified conditions such that 6.3 Calorimeter, made of metal (preferably copper or brass)
all water in the products remains in liquid form. with a tarnish-resistant coating and with all outer surfaces
highly polished. Its size shall be such that the bomb will be
3.2.5 net calorific value—a lower value calculated from the
completely immersed in water when the calorimeter is as-
gross calorific value. It is equivalent to the heat produced by
sembled. It shall have a device for stirring the water thoroughly
combustion of a unit quantity of solid fuel at a constant
and at a uniform rate, but with minimum heat input. Continu-
pressure of one atmosphere, under the assumption that all
ous stirring for 10 min shall not raise the calorimeter tempera-
water in the products remains in the form of vapor.
ture more than 0.01 °C (0.02 °F) starting with identical tem-
3.2.6 refuse-derived fuels—solid forms of refuse-derived
peratures in the calorimeter, room, and jacket. The immersed
fuels from which appropriate analytical samples may be
4 portion of the stirrer shall be coupled to the outside through a
prepared are defined as follows in ASTM STP 832:
material of low heat conductivity.
RDF-1—Wastes used as a fuel in as-discarded form with
only bulky wastes removed.
6.4 Jacket—The calorimeter shall be completely enclosed
RDF-2—Wastes processed to coarse particle size with or
within a stirred water jacket and supported so that its sides, top,
without ferrous metal separation.
and bottom are approximately 10 mm from the jacket walls.
RDF-3—Combustible waste fraction processed to particle
The jacket may be arranged so as to remain at constant
sizes, 95 % passing 2 in. square screening.
temperature or with provisions for rapidly adjusting the jacket
RDF-4—Combustible waste fraction processed into powder
temperature to equal that of the calorimeter for adiabatic
form, 95 % passing 10-mesh screening.
operation. It shall be constructed so that any water evaporating
RDF-5—Combustible waste fraction densified (compressed)
from the jacket will not condense on the calorimeter.
into the form of pellets, slugs, cubettes, or briquettes.
6.5 Thermometers—Temperatures in the calorimeter and
jacket shall be measured with the following thermometers or
4. Summary of Test Method
combinations thereof:
4.1 Calorific value is determined in this method by burning
6.5.1 Beckmann Differential Thermometer, having a range
a weighed analysis sample in an oxygen bomb calorimeter
of approximately 6 °C in 0.01 °C subdivisions reading upward
under controlled conditions. The calorific value is computed
and conforming to the requirements for Thermometer 115 °C,
from temperature observations made before and after
as prescribed in Specification E1. Each of these thermometers
combustion, taking proper allowance for thermometer and
shall be tested for accuracy against a known standard at
thermochemical corrections. Either isothermal or adiabatic
intervals no larger than 1 °C over the entire graduated scale.
calorimeter jackets may be used.
The maximum difference between any two test points shall not
be more than 0.02 °C.
5. Significance and Use
6.5.2 Calorimetric-Type Platinum Resistance Thermometer,
5.1 The calorific value, or heat of combustion, is a measure
25-, tested for accuracy against a known standard.
of the energy available from a fuel. Knowledge of this value is
6.5.3 Other Thermometers—A high precision electronic
essential in assessing the commercial worth of the fuel and to
thermometer employing balanced thermistors, or a quartz
provide the basis of contract between producer and user.
thermometer may be used, provided the temperature rise
6. Apparatus
indication is accurate within 60.003 °C per 1 °C rise.
6.1 Test Room—The apparatus should be operated in a room
6.6 Sample Holder—Samples shall be burned in an open
or area free of drafts that can be kept at a reasonably uniform
crucible of platinum, quartz, or acceptable base-metal alloy.
temperature and humidity for the time required for the deter-
Base-metal alloy crucibles are acceptable if after a few
mination. The apparatus should be shielded from direct sun-
preliminary firings the weight does not change significantly
light and radiation from other sources. Controlled room tem-
between tasks.
perature and humidity are highly desirable.
6.7 Firing Wire shall be 100 mm of No. 34 B&S nickel-
6.2 Oxygen Bomb, constructed of materials that are not
chromium alloy wire or 100 mm of No. 34 B&S iron wire.
affected by the combustion process or products sufficiently to
Equivalent platinum or palladium wire may be used provided
introduce measurable heat input or alteration of end products.
constant ignition energy is supplied or measured, and appro-
If the bomb is lined with platinum or gold, all openings shall be
priate corrections made.
sealed to prevent combustion products from reaching the base
6.8 Firing Circuit—A 6 to 16 V alternating or direct current
metal. The bomb shall be designed so that all liquid combus-
tion products can be completely recovered by washing the is required for ignition purposes with an ammeter or pilot light
in the circuit to indicate when current is flowing. A stepdown
inner surfaces. There shall be no gas leakage during a test. The
bomb shall be capable of withstanding a hydrostatic pressure transformer connected to an alternating current lighting circuit
test to 21 MPa (3000 psig) at room temperature without or batteries may be used.
stressing any part beyond its elastic limit.
6.9 CAUTION: The ignition circuit switch shall be of
momentary double-contact type, normally open, except when
held closed by the operator. The switch should be depressed
Thesaurus on Resource Recovery Terminology, ASTM STP 832, ASTM
International, 1983, p. 72. only long enough to fire the bomb.
´1
E711 − 23
7. Reagents 8.2.2 Bomb parts should be inspected carefully after each
use. Threads on the main closure should be checked frequently
7.1 Purity of Reagents—Reagent grade chemicals shall be
for wear. The bomb should be returned to the manufacturer
used in all tests. Unless otherwise indicated, it is intended that
occasionally for inspection and possibly proof of firing.
all reagents shall conform to the specifications of the Commit-
8.2.3 The oxygen supply cylinder should be equipped with
tee on Analytical Reagents of the American Chemical Society,
an approved type of safety device, such as a reducing valve, in
where such specifications are available. Other grades may be
addition to the needle valve and pressure gage used in
used, provided it is first ascertained that the reagent is of
regulating the oxygen feed to the bomb. Valves, gages, and
sufficiently high purity to permit its use without lessening the
gaskets must meet industry safety codes. Suitable reducing
accuracy of the determination.
valves and adaptors for 2 to 3.5 MPa (300 to 500 psig)
7.2 Purity of Water—Unless otherwise indicated, references
discharge pressure are obtainable from commercial sources of
to water shall be understood to mean reagent water, Type III,
compressed gas equipment. The pressure gage shall be checked
conforming to Specification D1193.
periodically for accuracy.
7.3 Benzoic Acid, Standard (C H COOH)—Use National 8.2.4 During ignition of a sample, the operator shall not
6 5
Bureau of Standards SRM (Standard Reference Material) permit any portion of his body to extend over the calorimeter.
benzoic acid. The crystals shall be pelletized before use.
9. Sampling
Commercially prepared pellets may be used provided they are
made from National Bureau of Standards benzoic acid. The
9.1 RDF products are frequently nonhomogeneous. Thus,
value of heat of combustion of benzoic acid, for use in the
significant care is needed to obtain a representative laboratory
calibration calculations, shall be in accordance with the value
sample for the RDF lot to be characterized.
listed in the National Bureau of Standards certificate issued
9.2 The sampling method for this procedure should be based
with the standard.
on agreement between the involved parties.
7.4 Methyl Orange, Methyl Red, or Methyl Purple
9.3 The laboratory sample must be air dried and particle size
Indicator—May be used to titrate the acid formed in the
reduced to pass a 0.5 mm screen as described in Practice E829.
combustion. The indicator selected shall be used consistently
in both calibrations and calorific determinations.
10. Standardization
7.5 Oxygen, free of combustible matter. Oxygen manufac-
10.1 Determine the energy equivalent of the calorimeter as
tured from liquid air, guaranteed to be greater than 99.5 %
the average of a series of ten individual runs, made over a
pure, will meet this requirement. Oxygen made by the electro-
period of not less than three days or more than five days. To be
lytic process may contain a small amount of hydrogen,
acceptable, the standard deviation of the series shall be
rendering it unfit without purification.
6.9 kJ ⁄°C (6.5 Btu/°C) or less (see Appendix X1, Table X1.1).
For this purpose, any individual run may be discarded only if
7.6 Sodium Carbonate, Standard Solution (0.34 N)—One
there is evidence indicating incomplete combustion. If this
millilitre of this solution should be equivalent to 20.0 J in the
nitric acid (HNO ) titration. Dissolve 18.02 g of anhydrous limit is not met, repeat the entire series until a series is obtained
with a standard deviation below the acceptable limit.
sodium carbonate (Na CO ) in water and dilute to 1 L. The
2 3
Na CO should be previously dried for 24 h at 105 °C. The
2 3
10.2 The weights of the pellets of benzoic acid in each
buret used for the HNO titration shall be of such accuracy that
series should be regulated to yield the same temperature rise as
estimations to 0.1 mL can be made. A more dilute standard
that obtained with the various samples tested in the individual
solution may be used for higher sensitivity.
laboratories. The usual range of weight is 0.9 to 1.3 g. Make
each determination in accordance with the procedure described
8. Precautions
in Section 11, and compute the corrected temperature rise, T, as
8.1 Due to the origins of RDF in municipal waste, precau-
described in 12.1. Determine the corrections for HNO and
tions should be observed when conducting tests on the
firing wire as described in 12.2 and substitute into the follow-
samples. Recommended hygienic practices include use of
ing equation:
gloves when handling RDF and washing hands before eating or
E 5 @~H!~g!1e 1e 1e # × t (1)
1 3 4
smoking.
where:
8.2 The following precautions are recommended for safe
E = energy equivalent, J/°C,
calorimeter operation:
H = heat of combustion of benzoic acid, as stated in the
8.2.1 The weight of solid fuel sample and the pressure of the
National Bureau of Standards certificate, J/g,
oxygen admitted to the bomb must not exceed the bomb
g = weight of benzoic acid, g,
manufacturer’s recommendations.
t = corrected temperature rise, °C,
e = titration correction, J,
Reagent Chemicals, American Chemical Society Specifications, American
Chemical Society, Washington, DC. For suggestions on the testing of reagents not
listed by the American Chemical Society, see Analar Standards for Laboratory
Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia ASTM Subcommittee E38.01 is currently in the process of developing
and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, procedures for sampling RDF-3 and the preparation of an analysis sample. The
MD. chairman of E38.01 should be contacted for details.
´1
E711 − 23
charge at the start of the sixth minute and record the time and
e = fuse wire correction, J, and
temperature, T . Add to this temperature 60 % of the expected
e = correction for ignition energy if measured and corrected
a
temperature rise and record the time at which the 60 % point is
for, J.
reached (Note 3). After the rapid rise period (about 4 to 5 min),
10.3 Standardization tests should be repeated after changing
record temperatures at 1 min intervals on the minute until the
any part of the calorimeter and occasion
...