ASTM E711-87(1996)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Please contact ASTM International (www.astm.org) for the latest information.
Designation: E 711 – 87 (Reapproved 1996)
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.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (ϵ) indicates an editorial change since the last revision or reapproval.
1 Btu (International Table)=1055.06 absolute joules
1. Scope
1 Calorie (International Table)=4.1868 absolute joules
1.1 This test method covers the determination of the gross
1 Btu/lb=2.326 J/g
calorific value of a prepared analysis sample of solid forms of
1.8 Btu/lb=1.0 cal/g
refuse-derived fuel (RDF) by the bomb calorimeter method.
3.1.2 gross calorific value—the heat produced by combus-
1.2 This standard does not purport to address all of the
tion of a unit quantity of solid fuel, at constant volume, in an
safety concerns, if any, associated with its use. It is the
oxygen bomb calorimeter under specified conditions such that
responsibility of the user of this standard to establish appro-
all water in the products remains in liquid form.
priate safety and health practices and determine the applica-
3.1.3 net calorific value—a lower value calculated from the
bility of regulatory limitations prior to use. For specific
gross calorific value. It is equivalent to the heat produced by
cautionary and precautionary statements see 6.10 and Section
combustion of a unit quantity of solid fuel at a constant
8.
pressure of one atmosphere, under the assumption that all
water in the products remains in the form of vapor.
2. Referenced Documents
3.2 Definitions of Terms Specific to This Standard:
2.1 ASTM Standards:
2 3.2.1 calorimeter—describes the bomb, the vessel with
D1193 Specification for Reagent Water
stirrer, and the water in which the bomb is immersed.
D3177 TestMethodforTotalSulfurintheAnalysisSample
3 3.2.2 energy equivalent—the energy required to raise the
of Coal and Coke
temperature (Note 2) of the calorimeter system 1°C (or 1°F)
E1 Specification for ASTM Thermometers
pergramofsample.Thisisthenumberthatismultipliedbythe
E180 Practice for Determining the Precision of ASTM
corrected temperature rise in degrees and divided by the
Methods forAnalysis andTesting of Industrial Chemicals
sample weight in grams to give the gross calorific value after
E775 Test Methods forTotal Sulfur in theAnalysis Sample
thermochemical corrections have been applied.
of Refuse-Derived Fuel
E790 Test Method for Residual Moisture in a Refuse- NOTE 2—Temperature change is measured in thermal units. Tempera-
ture changes may also be recorded in electromotive force, ohms, or other
Derived Fuel Analysis Sample
units when other types of temperature sensors are used. Consistent units
E829 Practice for Preparing Refuse-Derived Fuels (RDF)
must be used in both the standardization and actual calorific determina-
Laboratory Samples for Analysis
tion. Time is expressed in minutes. Weights are measured in grams.
3. Terminology
3.2.3 refuse-derived fuels—solid forms of refuse-derived
fuels from which appropriate analytical samples may be
3.1 Definitions:
prepared are defined as follows in ASTM STP 832:
3.1.1 calorific value—the heat of combustion of a unit
RDF-1—Wastes used as a fuel in as-discarded form with
quantityofasubstance.Itmaybeexpressedinjoulespergram
only bulky wastes removed.
(J/g), British thermal units per pound (Btu/lb), or calories per
RDF-2—Wastes processed to coarse particle size with or
gram (cal/g) when required.
without ferrous metal separation.
NOTE 1—The unit equivalents are as follows:
RDF-3—Combustible waste fraction processed to particle
sizes, 95% passing 2-in. square screening.
1 RDF-4—Combustible waste fraction processed into powder
This test method is under the jurisdiction ofASTM Committee D34 on Waste
form, 95% passing 10-mesh screening.
Management and is the direct responsibility of Subcommittee D34.06 on Recovery
and Reuse.
RDF-5—Combustiblewastefractiondensified(compressed)
Current edition approved Aug. 28, 1987. Published October 1987.
into the form of pellets, slugs, cubettes, or briquettes.
Annual Book of ASTM Standards, Vol 11.01.
Annual Book of ASTM Standards, Vol 05.05.
Annual Book of ASTM Standards, Vol 14.03.
5 7
Annual Book of ASTM Standards, Vol 15.05. Thesaurus on Resource Recovery Terminology, ASTM STP 832, ASTM, 1983,
Annual Book of ASTM Standards, Vol 11.04. p. 72.
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Please contact ASTM International (www.astm.org) for the latest information.
E 711 – 87 (1996)
4. Summary of Test Method eters of equal or better accuracy are satisfactory. These
thermometers shall be tested for accuracy against a known
4.1 Calorific value is determined in this method by burning
standard (preferably by the National Bureau of Standards) at
a weighed analysis sample in an oxygen bomb calorimeter
intervals no greater than 2.0°C (3.6°F) over the entire gradu-
under controlled conditions. The calorific value is computed
ated scale.The maximum difference in correction between any
from temperature observations made before and after combus-
two test points shall not be more than 0.02°C (0.04°F).
tion, taking proper allowance for thermometer and thermo-
6.5.2 Beckmann Differential Thermometer, having a range
chemical corrections. Either isothermal or adiabatic calorim-
of approximately 6°C in 0.01°C subdivisions reading upward
eter jackets may be used.
and conforming to the requirements for Thermometer 115°C,
as prescribed in Specification E1E1. Each of these thermom-
5. Significance and Use
eters shall be tested for accuracy against a known standard at
5.1 The calorific value, or heat of combustion, is a measure
intervals no larger than 1°C over the entire graduated scale.
of the energy available from a fuel. Knowledge of this value is
The maximum difference between any two test points shall not
essential in assessing the commercial worth of the fuel and to
be more than 0.02°C.
provide the basis of contract between producer and user.
6.5.3 Calorimetric-Type Platinum Resistance Thermometer,
25-, tested for accuracy against a known standard.
6. Apparatus
6.5.4 Other Thermometers—A high precision electronic
6.1 TestRoom—Theapparatusshouldbeoperatedinaroom
thermometer employing balanced thermistors or a quartz
or area free of drafts that can be kept at a reasonably uniform
thermometer may be used, provided the temperature rise
temperature and humidity for the time required for the deter-
indication is accurate within 6 0.003°C per 1°C rise.
mination. The apparatus should be shielded from direct sun-
6.6 Thermometer Accessories—A magnifier is required for
light and radiation from other sources. Controlled room tem-
reading mercury-in-glass thermometers to one tenth of the
perature and humidity are desirable.
smallest scale division. This shall have a lens and holder
6.2 Oxygen Bomb, constructed of materials that are not
designed so as to introduce no significant errors due to
affected by the combustion process or products sufficiently to
parallax. A Wheatstone bridge and galvanometer capable of
introduce measurable heat input or alteration of end products.
measuring resistance to 0.0001 Ω are necessary for use with
Ifthebombislinedwithplatinumorgold,allopeningsshallbe
resistance thermometers.
sealed to prevent combustion products from reaching the base
6.7 Sample Holder—Samples shall be burned in an open
metal. The bomb shall be designed so that all liquid combus-
crucible of platinum, quartz, or acceptable base-metal alloy.
tion products can be completely recovered by washing the
Base-metal alloy crucibles are acceptable if after a few
inner surfaces.There shall be no gas leakage during a test.The
preliminary firings the weight does not change significantly
bomb shall be capable of withstanding a hydrostatic pressure
between tasks.
test to 21 MPa (3000 psig) at room temperature without
6.8 Firing Wire shall be 100 mm of No. 34 B & S
stressing any part beyond its elastic limit.
nickel-chromium alloy wire or 100 mm of No. 34B&S iron
6.3 Calorimeter,madeofmetal(preferablycopperorbrass)
wire. Equivalent platinum or palladium wire may be used
with a tarnish-resistant coating and with all outer surfaces
providedconstantignitionenergyissupplied,ormeasured,and
highly polished. Its size shall be such that the bomb will be
appropriate corrections made.
completely immersed in water when the calorimeter is as-
6.9 Firing Circuit—A6to16-Valternatingordirectcurrent
sembled.Itshallhaveadeviceforstirringthewaterthoroughly
is required for ignition purposes with an ammeter or pilot light
and at a uniform rate, but with minimum heat input. Continu-
in the circuit to indicate when current is flowing. A stepdown
ous stirring for 10 min shall not raise the calorimeter tempera-
transformer connected to an alternating current lighting circuit
turemorethan0.01°C(0.02°F)startingwithidenticaltempera-
or batteries may be used.
tures in the calorimeter, room, and jacket. The immersed
6.10 CAUTION: The ignition circuit switch shall be of
portion of the stirrer shall be coupled to the outside through a
momentary double-contact type, normally open, except when
material of low heat conductivity.
held closed by the operator. The switch should be depressed
6.4 Jacket—The calorimeter shall be completely enclosed
only long enough to fire the bomb.
withinastirredwaterjacketandsupportedsothatitssides,top,
7. Reagents
and bottom are approximately 10 mm from the jacket walls.
The jacket may be arranged so as to remain at constant
7.1 Purity of Reagents—Reagent grade chemicals shall be
temperature or with provisions for rapidly adjusting the jacket
used in all tests. Unless otherwise indicated, it is intended that
temperature to equal that of the calorimeter for adiabatic
all reagents shall conform to the specifications of the Commit-
operation. It shall be constructed so that any water evaporating
tee onAnalytical Reagents of theAmerican Chemical Society,
from the jacket will not condense on the calorimeter.
where such specifications are available. Other grades may be
6.5 Thermometers—Temperatures in the calorimeter and
used, provided it is first ascertained that the reagent is of
jacket shall be measured with the following thermometers or
combinations thereof:
“Reagent Chemicals,American Chemical Society Specifications,”Am. Chemi-
6.5.1 Mercury-in-Glass Thermometers, conforming to the
cal Soc., Washington, DC. For suggestions on the testing of reagents not listed by
requirements for Thermometers 116°C or 117°C (56°F or
the American Chemical Society, see “Analar Standards for Laboratory U.K.
57°F) as prescribed in Specification E1E1. Other thermom- Chemicals,” BDH Ltd., Poole, Dorset, and the “United States Pharmacopeia.”
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Please contact ASTM International (www.astm.org) for the latest information.
E 711 – 87 (1996)
sufficiently high purity to permit its use without lessening the 9. Sampling
accuracy of the determination.
9.1 RDF products are frequently nonhomogeneous. For this
7.2 Purity of Water—Unlessotherwiseindicated,references
reason significant care should be exercised to obtain a repre-
to water shall be understood to mean reagent water, Type III,
sentativelaboratorysamplefortheRDFlottobecharacterized.
conforming to Specification D1193D1193.
9.2 Thesamplingmethodforthisprocedureshouldbebased
7.3 Benzoic Acid, Standard (C H COOH)—Use National
6 5 on agreement between the involved parties.
Bureau of Standards SRM (Standard Reference Material)
9.3 The laboratory sample must be air-dried and particle
benzoic acid. The crystals shall be pelletized before use.
size reduced to pass a 0.5-mm screen as described in Practice
Commercially prepared pellets may be used provided they are
E829E829.
made from National Bureau of Standards benzoic acid. The
10. Standardization
value of heat of combustion of benzoic acid, for use in the
calibration calculations, shall be in accordance with the value
10.1 Determine the energy equivalent of the calorimeter as
listed in the National Bureau of Standards certificate issued
the average of a series of ten individual runs, made over a
with the standard.
period of not less than 3 days or more than 5 days. To be
7.4 Methyl Orange, Methyl Red, or Methyl Purple
acceptable, the standard deviation of the series shall be 6.9
Indicator—may be used to titrate the acid formed in the
kJ/°C (6.5 Btu/°C) or less (seeAppendix X1, Table X1.1). For
combustion. The indicator selected shall be used consistently
this purpose, any individual run may be discarded only if there
in both calibrations and calorific determinations.
is evidence indicating incomplete combustion. If this limit is
7.5 Oxygen, free of combustible matter. Oxygen manufac- not met, repeat the entire series until a series is obtained with
tured from liquid air, guaranteed to be greater than 99.5%
a standard deviation below the acceptable limit.
pure, will meet this requirement. Oxygen made by the electro- 10.2 The weights of the pellets of benzoic acid in each
lytic process may contain a small amount of hydrogen render-
seriesshouldberegulatedtoyieldthesametemperatureriseas
ing it unfit without purification. that obtained with the various samples tested in the individual
7.6 Sodium Carbonate, Standard Solution (0.34 N)—One laboratories. The usual range of weight is 0.9 to 1.3 g. Make
millilitre of this solution should be equivalent to 20.0 J in the eachdeterminationinaccordancewiththeproceduredescribed
nitric acid (HNO ) titration. Dissolve 18.02 g of anhydrous inSection11,andcomputethecorrectedtemperaturerise,T,as
sodium carbonate (Na CO ) in water and dilute to 1 L. The described in 12.1. Determine the corrections for HNO and
2 3 3
Na CO should be previously dried for 24 h at 105°C. The firing wire as described in 12.2 and substitute into the follow-
2 3
buretusedfortheHNO titrationshallbeofsuchaccuracythat ing equation:
estimations to 0.1 mL can be made. A more dilute standard
E 5[~H! ~g! 1 e 1 e 1 e # 3 t (1)
1 3 4
solution may be used for higher sensitivity.
where:
E = energy equivalent, J/°C,
8. Precautions
H = heat of combustion of benzoic acid, as stated in the
8.1 Due to the origins of RDF in municipal waste, common
National Bureau of Standards certificate, J/g,
sense dictates that some precautions should be observed when
g = weig
...