SIST-TS CEN/TS 16023:2014

SLOVENSKI STANDARD
SIST-TS CEN/TS 16023:2014
01-julij-2014
.DUDNWHUL]DFLMDRGSDGNRY'RORþHYDQMHVHåLJQHYUHGQRVWLLQL]UDþXQNXULOQH
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Characterization of waste - Determination of gross calorific value and calculation of net
calorific value
Charakterisierung von Abfällen - Bestimmung des Brennwertes und Berechnung des
Heizwertes
Caractérisation des déchets - Détermination du pouvoir calorifique brut et calcul du
pouvoir calorifique net
Ta slovenski standard je istoveten z: CEN/TS 16023:2013
ICS:
13.030.01 Odpadki na splošno Wastes in general
SIST-TS CEN/TS 16023:2014 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST-TS CEN/TS 16023:2014

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SIST-TS CEN/TS 16023:2014


TECHNICAL SPECIFICATION
CEN/TS 16023

SPÉCIFICATION TECHNIQUE

TECHNISCHE SPEZIFIKATION
November 2013
ICS 13.030.01
English Version
Characterization of waste - Determination of gross calorific value
and calculation of net calorific value
Caractérisation des déchets - Détermination du pouvoir Charakterisierung von Abfällen - Bestimmung des
calorifique supérieur et calcul du pouvoir calorifique Brennwertes und Berechnung des Heizwertes
inférieur
This Technical Specification (CEN/TS) was approved by CEN on 6 August 2013 for provisional application.

The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the CEN/TS can be converted into a European Standard.

CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available
promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)
until the final decision about the possible conversion of the CEN/TS into an EN is reached.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2013 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 16023:2013: E
worldwide for CEN national Members.

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Contents Page
Foreword .3
Introduction .4
1 Scope .5
2 Normative references .5
3 Terms and definitions .5
4 Principle .6
4.1 Gross calorific value .6
4.2 Net calorific value .6
5 Reagents .6
6 Apparatus .7
7 Sample storage .8
8 Sample preparation .8
9 Procedure .9
9.1 General .9
9.2 General preparations, measurements and temperature corrections . 10
9.3 Calibration . 13
9.4 Samples . 13
10 Calculation of effective heat capacity. 14
11 Gross calorific value . 15
12 Calculation of net calorific value. 16
12.1 General . 16
12.2 Net calorific value at constant pressure . 16
13 Expression of results . 16
14 Quality control . 17
15 Test report . 17
Annex A (informative) Example of a calorimeter . 18
Annex B (informative) Temperature evolution . 19
Annex C (informative) Calculation of the gross calorific value – Correct calculation versus the
simplified calculation . 20
C.1 Correct calculation . 20
C.2 Sulfur correction . 21
C.3 Nitrogen correction. 21
C.4 Halogens correction . 21
C.5 Influence of the thermo-chemical corrections . 22
Annex D (informative) Typical hydrogen contents in waste products . 24
Annex E (informative) Summary of general requirements and recommendations . 25
Bibliography . 26

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Foreword
This document (CEN/TS 16023:2013) has been prepared by Technical Committee CEN/TC 292
“Characterization of waste”, the secretariat of which is held by NEN.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria, Croatia, Cyprus,
Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany,
Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
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Introduction
This method is a quick and easy way to evaluate the suitability of waste to be treated by thermal processes.
The determination of gross calorific value is carried out without thermo-chemical corrections. These
corrections typically result in minor changes of the result. The influence of these corrections is shown in
Annex C.
The result obtained is the gross calorific value at constant volume with both the water of the combustion
products and the moisture of the waste as liquid water.
The net calorific value is obtained by calculation from the gross calorific value. For the purpose of this
Technical Specification, the value of the net calorific value does not need to be determined exactly. The
correction for hydrogen is simplified by the use of typical hydrogen contents derived from table values of
hydrogen contents in common types of waste.
This Technical Specification specifies a quick method to determine calorific value; a more comprehensive
analysis is described in ISO 1928.
Waste can contain water and (unburnable) solids in large amounts. Therefore their calorific value – especially
on the “as received” basis – can be quite low. For some purposes it may be sufficient to determine the gross
calorific value only, and not the net calorific value.
WARNING — Strict adherence to all of the provisions prescribed in this Technical Specification
should ensure against explosive rupture of the bomb, or a blow-out, provided that the bomb is of
proper design and construction and in good mechanical condition. Anyone dealing with waste and
sludge analysis is required to be aware of the typical risks of this kind of material irrespective of the
parameter to be determined. Waste and sludge samples may contain hazardous (e.g. toxic, reactive,
flammable, infectious) substances, which can be liable to biological and/or chemical reaction.
Consequently, it is recommended that these samples be handled with special care. The gases that
may be produced by microbiological or chemical activity are potentially flammable and will pressurize
sealed bottles. Bursting bottles are likely to result in hazardous shrapnel, dust and/or aerosol.
National regulations should be followed with respect to all hazards associated with this method.
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1 Scope
This Technical Specification specifies a simplified method for the determination of the gross calorific value of
waste at constant volume and at the reference temperature of 25 °C in a bomb calorimeter calibrated by
combustion of certified benzoic acid. This Technical Specification does not include thermo-chemical
corrections.
This Technical Specification also specifies a simplified calculation of the net calorific value from the gross
calorific value.
This Technical Specification is applicable for the evaluation of suitability of waste to be treated by thermal
processes and for the energy to be recovered.
This Technical Specification is applicable to all kinds of waste.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
EN 13965-2:2010, Characterization of waste - Terminology - Part 2: Management related terms and
definitions
EN 14346, Characterization of waste - Calculation of dry matter by determination of dry residue or water
content
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 13965-2:2010 and the following
apply.
3.1
corrected temperature rise
change in calorimeter temperature caused solely by the processes taking place within the combustion bomb
Note 1 to entry: It is the total observed temperature rise corrected for heat exchange, stirring power etc.
3.2
gross calorific value at constant volume
absolute value of the specific energy of combustion, in Joules, for unit mass of waste burned in oxygen in a
calorimetric bomb under the conditions specified
Note 1 to entry: The products of combustion are assumed to consist of gaseous oxygen, nitrogen, carbon dioxide and
sulfur dioxide, of liquid water (in equilibrium with its vapour) saturated with carbon dioxide under the conditions of the
bomb reaction, and of solid ash, all at the reference temperature.
3.3
net calorific value at constant pressure
absolute value of the specific energy of combustion, in Joules, for unit mass of waste burned in oxygen at
constant pressure under such conditions that all the water of the reaction products remains as water vapour
(in a hypothetical state at 0,1 MPa)
Note 1 to entry: The other products are assumed to remain at the reference temperature.
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4 Principle
4.1 Gross calorific value
A weighed portion of the waste sample is burned in a high-pressure oxygen atmosphere in a bomb
calorimeter under specified conditions. The effective heat capacity of the calorimeter is determined in
calibration experiments by combustion of certified benzoic acid under similar conditions, accounted for in the
certificate. The corrected temperature rise is established from observations of temperature before, during and
after the combustion reaction takes place. The duration and frequency of the temperature observations
depend on the type of calorimeter used. Water is added to the bomb initially to give a saturated vapour phase
prior to combustion, thereby allowing all the water formed, from the hydrogen and moisture in the sample, to
be regarded as liquid water.
The gross calorific value is calculated from the corrected temperature rise and the effective heat capacity of
the calorimeter, without corrections made for contributions from ignition energy, combustion of the fuse(s) and
for thermal effects from side reactions such as the formation of nitric acid.
4.2 Net calorific value
The net calorific value at constant pressure is calculated from the gross calorific value at constant volume
using typical values of hydrogen content. The calculation is made without corrections due to the oxygen and
nitrogen content of the samples.
5 Reagents
5.1 Oxygen, at a pressure high enough to fill the bomb to 3 MPa, pure with an assay of at least 99,5 %
(V/V), and free from combustible matter.
NOTE Oxygen made by the electrolytic process can contain up to 4 % (V/V) hydrogen.
5.2 Ignition wire, of nickel-chromium 0,16 mm to 0,20 mm in diameter, platinum 0,05 mm to 0,10 mm in
diameter, or another suitable conducting wire with well-characterized thermal behaviour during combustion.
Knowing the gross calorific value of the fuse is necessary if an accurate calculation according to Annex C is to
be carried out. This information is not required for the method described in this Technical Specification.
5.3 Cotton fuse, of cellulose cotton, or equivalent, if required.
Knowing the gross calorific value of the fuse is necessary if an accurate calculation according to Annex C is to
be carried out. This information is not required for the method described in this specification. It is necessary to
use a fuse with the same length and sections both in the calibration step and in the measurements.
5.4 Combustion aids, of known gross calorific value, composition and purity, such as benzoic acid,
n-dodecane, paraffin oil, combustion bags or capsules may be used.
5.5 Benzoic acid, of calorimetric-standard quality, certified by (or with certification unambiguously
traceable to) a recognized standardizing authority.
The benzoic acid is burned in the form of pellets. It is normally used without drying or any treatment other than
pelletising; consult the sample certificate. The benzoic acid shall be used as close to certification conditions as
is feasible; significant modifications to the conditions specified should be accounted for in accordance with the
directions in the certificate.
5.6 Gelatine or acetobutyrate capsules.
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6 Apparatus
6.1 General
The calorimeter (see Figure A.1), consists of the assembled combustion bomb, a can (with or without lid),
stirrer, water, temperature sensor, and leads with connectors inside the calorimeter can, required for ignition
of the sample or as part of temperature measurement or control circuits. During measurements, the
calorimeter is enclosed in a thermostat. The manner in which the thermostat temperature is controlled defines
the working principle of the instrument and hence the strategy for evaluation of the corrected temperature rise.
In combustion calorimetric instruments with a high degree of automation, especially in the evaluation of the
results, the calorimeter is in a few cases not as well-defined as the traditional, classical-type calorimeter.
Using such an automated calorimeter is, however, within the scope of this Technical Specification as long as
the basic requirements are met with respect to calibration conditions, comparability between calibration and
waste experiments, ratio of sample mass to bomb volume, oxygen pressure, bomb liquid, reference
temperature of the measurements and repeatability of the results.
Equipment, adequate for determinations of calorific value in accordance with this Technical Specification, is
specified below.
6.2 Calorimeter with thermostat
6.2.1 Combustion bomb, capable of safely withstanding the pressures developed during combustion. The
design shall permit complete recovery of all liquid products. The material of construction shall resist corrosive
acids resulting from the combustion of waste. A suitable internal volume of the bomb would be from 250 ml to
350 ml.
6.2.2 Calorimeter can, made of metal, highly polished on the outside and capable of holding an amount of
water sufficient to completely cover the flat upper surface of the bomb while the water is being stirred.
6.2.3 Stirrer, working at constant speed.
The stirrer shaft should have a low-heat conduction and/or a low-mass section below the cover of the
surrounding thermostat to minimize transmission of heat to or from the system; this is of particular importance
when the stirrer shaft is in direct contact with the stirrer motor.
6.2.4 Thermostat (water jacket), completely surrounding the calorimeter, with an air gap of approximately
10 mm separating calorimeter and thermostat.
The mass of water of a thermostat intended for isothermal operation shall be sufficiently large to outbalance
thermal disturbances from the outside. The temperature should be controlled to within ± 0,1 K or better
throughout the experiment.
6.2.5 Temperature measuring instrument, capable of indicating temperature with a resolution of at least
0,001 K so that temperature intervals of 2 K to 3 K can be determined with a resolution of 0,002 K or better.
The absolute temperature shall be known to the nearest 0,1 K at the reference temperature of the calorimetric
measurements. The temperature measuring device should be linear, or linearized, in its response to changes
in temperature over the interval it is used.
6.3 Crucible, of silica, nickel-chromium, platinum or similar non-reactive material.
The crucible should be 15 mm to 25 mm in diameter, flat based and about 20 mm deep. Silica crucibles
should be about 1,5 mm thick and metal crucibles about 0,5 mm thick. Base metal alloy crucibles are suitable
if after a few preliminary firings the weight does not change significantly between tests.
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6.4 Ancillary pressure equipment
6.4.1 Pressure regulator, to control the filling of the bomb with oxygen.
6.4.2 Pressure gauge, e.g. 0 MPa to 5 MPa, to indicate the pressure in the bomb with a resolution of
0,05 MPa.
6.4.3 Relief valve or bursting disk, operating at 3,5 MPa, and installed in the filling line, to prevent
overfilling the bomb.
CAUTION — Equipment for high-pressure oxygen shall be kept free of oil and grease (high vacuum
grease recommended by the manufacturer can be used according to the operating manual of the
instrument). Do not test or calibrate the pressure gauge with hydrocarbon fluid.
6.5 Timer
6.6 Balances
6.6.1 Balance for weighing the sample, fuse etc., with an accuracy of at least 0,1 mg; 0,01 mg is
preferable and is recommended when the sample mass is of the order of 0,5 g or less.
6.6.2 Balance for weighing the calorimeter water, with an accuracy of at least 0,5 g (unless water can be
dispensed into the calorimeter by volume with the required accuracy).
6.7 Pellet press, capable of applying a force of about 100 kN, either hydraulically or mechanically, and
having a die suitable to press a pellet with a diameter of about 13 mm and a mass of (1 ± 0,1) g.
7 Sample storage
Biologically active laboratory samples should be stored at about 4 °C and the analysis should be carried out
within seven days after sampling. If this is not possible, the samples should be preserved further, for example
by freezing or freeze drying in order to minimize biodegradation and loss of volatile compounds.
8 Sample preparation
The goal of any sample preparation procedure is to prepare a test sample in which the composition is not
significantly changed compared to the laboratory sample. Due to the different properties of the various kinds
of materials there is no general procedure available.
Recommendations for sample pretreatment are given in EN 15002.
Depending on the nature of the sample material a drying step might be required. If necessary, air-dry the
complete sample or dry it in a ventilated drying oven at a temperature not exceeding 40 °C or in a freeze
dryer. The drying time depends on the technique chosen and the type of sample.
For solid waste materials, one or more particle size reduction steps might be needed in order to achieve a
homogeneous and representative test portion. The choice of the technique depends on the nature of the
sample and on the particle size needed. Typically, particle size reduction is a multi-step operation that implies
the use of a sequence of different techniques like crushing, cutting or grinding.
The particle size of the analysis sample material of solid waste samples for the determination of calorific value
shall be less than 1 mm and preferably less than 0,2 mm.
Determination of the moisture content of the resulting analysis sample shall be carried out according to
EN 14346.
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9 Procedure
9.1 General
The calorimetric determination consists of two separate operations under the same specified conditions:
— combustion of the calibrant (benzoic acid);
— combustion of the sample.
The procedure for both operations is essentially the same.
In the calibration experiment, the “effective heat capacity” of the calorimeter is determined (see Clause 10).
Both experiments consist of carrying out quantitatively a combustion reaction (in high-pressure oxygen in the
bomb) to defined products of combustion and of measuring the change in temperature caused by the total
bomb process.
The temperature measurements required for the evaluation of the corrected temperature rise θ are made
during a fore period, a main (= reaction) period, and an after period as outlined in Figure 1. For the adiabatic
type calorimeter, the fore and after periods need, in principle, be only as long as required to establish the
initial (firing) and final temperatures, respectively. For the isoperibol (isothermal jacket) and the static-jacket
type calorimeters, the fore and after periods serve to establish the heat exchange properties of the calorimeter
required to allow proper correction for heat exchange between calorimeter and thermostat during the main
period when combustion takes place. The fore and after periods shall then be longer.

Key
t
1 fore period initial temperature, in °C
i
t
2 main period temperature of the jacket,
j
in °C
t
3 after period final temperature, in °C
f
4 ignition τ time, in min
Figure 1 — Time-temperature curve (isoperibol calorimeter)
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The power of stirring shall be maintained constant throughout experiments that call for a constant rate of
stirring. An excessive rate of stirring results in an undesirable increase in the power of stirring with ensuing
difficulties in keeping it constant. A wobbling stirrer is likely to cause significant short-term variations in stirring
power.
During combustion, the bomb head will become noticeably hotter than other parts of the bomb, and it is
important to have enough well-stirred water above it to maintain reasonably small temperature gradients in the
calorimeter water during the rapid part of the rise in temperature.
9.2 General preparations, measurements and temperature corrections
9.2.1 Preparation of the bomb
Weigh the combustible fuse and/or ignition wire either with a resolution of at least 0,1 mg, or keep its mass
constant, within specified limits, for all experiments (calibration and waste sample experiments). Fasten the
ignition wire tautly between the electrodes in the bomb. Check the resistance of the ignition circuit of the
bomb; for most bombs, it should not exceed 5 Ω to 10 Ω, measured between the outside connectors of the
bomb head, or between the connector for the insulated electrode and the bomb head.
Tie, or attach firmly, the fuse to the ignition wire.
Place the crucible with its content (according to 9.3 or 9.4) in its support and bring the fuse into contact with
the content. Make sure that the position of the crucible in the assembled bomb is symmetrical with respect to
the surrounding bomb wall.
When the ignition wire is combustible as well as electrically conducting, an alternative procedure may be
adopted. A longer piece of wire, enough to make an open loop, is connected to the electrodes. After mounting
of the crucible, the loop is brought in contact with the sample pellet or capsule. (In some cases the ignition
process is better controlled when the wire is kept at a small distance above the sample pellet.) Care should be
taken to prevent any contact between ignition wire and crucible, in particular when a metal crucible is used
since this would result in shorting the ignition circuit. A special fuse is superfluous under these conditions. The
resistance of the ignition circuit of the bomb will be increased by a small amount only. For closer details of
preparing the bomb also refer to the manufacturer's instructions.
Add a defined amount of distilled water to the bomb. The amount shall always be exactly the same in
calibration and in sample experiments. As a main principle (1,0 ± 0,1) ml distilled water is added into the
bomb. For some waste samples (and some calorimeters) the complete combustion can be achieved by
omitting the addition of distilled water to the bomb. In some cases the total absorption of the gaseous
combustion products might require the use of a larger amount of distilled water (e.g. 5 ml).
Assemble the bomb.
Charge the bomb slowly with oxygen to obtain a pressure of (3,0 ± 0,2) MPa. The same procedure shall be
used both in calibration and in sample experiments. If the bomb is inadvertently charged with oxygen above
3,3 MPa, discard the test and begin again.
WARNING — Do not reach over the bomb during charging.
9.2.2 Assembling the calorimeter
Bring the calorimeter water to within ± 0,3 K of the selected initial temperature and fill the calorimeter can with
the required amount. This quantity of water in the calorimeter can shall be the same to within 0,5 g or better in
all experiments.
Place the bomb in the calorimeter can.
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