EN ISO 21911-1:2023

Solid recovered fuels - Determination of self-heating - Part 1: Isothermal calorimetry (ISO 21911-1:2022)

This document specifies an analytical method for quantification of the spontaneous heat generation from solid recovered fuels using isothermal calorimetry.
This document gives guidance on the applicability and use of the specified analytical method. It further establishes procedures for sampling and sample handling of solid recovered fuels prior to the analysis of spontaneous heat generation.
The test procedure given in this document quantifies the thermal power (heat flow) of the sample during the test. It does not identify the source of self-heating in the test portion analysed.

Feste Sekundärbrennstoffe - Bestimmung der Selbsterhitzung - Teil 1: Isotherme Kalorimetrie (ISO 21911-1:2022)

Dieses Dokument legt ein Analyseverfahren zur quantitativen Bestimmung der spontanen Wärmeerzeugung von festen Sekundärbrennstoffen unter Anwendung der isothermen Kalorimetrie fest.
Dieses Dokument liefert Hinweise zur Anwendbarkeit und Anwendung des festgelegten Analyseverfahrens. Es legt außerdem Verfahren für die Probenahme und Handhabung von Proben fester Sekundärbrennstoffe vor der Analyse der spontanen Wärmeerzeugung fest.
Mit dem in diesem Dokument angeführten Prüfverfahren wird die thermische Leistung (der Wärmestrom) der Probe während der Prüfung quantitativ bestimmt. Die Quelle der Selbsterhitzung in der analysierten Prüfmenge wird nicht ermittelt.

Combustibles solides de récupération - Détermination de l'auto-échauffement - Partie 1: Détermination calorimétrique isotherme (ISO 21911-1:2022)

Le présent document spécifie une méthode d'analyse pour la quantification, à l'aide de la détermination calorimétrique isotherme, de la production spontanée de chaleur par les combustibles solides de récupération.
Le présent document donne des lignes directrices concernant l'applicabilité et l'utilisation de la méthode d'analyse spécifiée. Il établit en outre des procédures d'échantillonnage et de manipulation des échantillons de combustibles solides de récupération avant l'analyse de la production spontanée de chaleur.
Le mode opératoire d'essai fourni dans le présent document quantifie la puissance thermique (flux thermique) de l'échantillon pendant l'essai. Il n'identifie pas la source de l'auto-échauffement dans la prise d'essai analysée.

Trdna alternativna goriva - Določanje samosegrevanja - 1. del: Izotermalna kalorimetrija (ISO 21911-1:2022)

General Information

• Status: Published
• Publication Date: 29-Aug-2023
• ICS: 75.160.10 - Solid fuels
• Technical Committee: CEN/TC 343 - Solid Recovered Fuels
• Drafting Committee: CEN/TC 343 - Solid Recovered Fuels
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 30-Aug-2023
• Due Date: 25-Jun-2025
• Completion Date: 30-Aug-2023
• Ref Project: oSIST prEN ISO 21911-1:2023 - Solid recovered fuels - Determination of self-heating - Part 1: Isothermal calorimetry (ISO 21911-1:2022)

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN ISO 21911-1:2023
01-maj-2023
Trdna alternativna goriva - Določanje samosegrevanja - 1. del: Izotermalna
kalorimetrija (ISO 21911-1:2022)
Solid recovered fuels - Determination of self-heating - Part 1: Isothermal calorimetry (ISO
21911-1:2022)
Feste Sekundärbrennstoffe - Bestimmung der Selbsterhitzung - Teil 1: Isotherme
Kalorimetrie (ISO 21911-1:2022)
Combustibles solides de récupération - Détermination de l'auto-échauffement - Partie 1:
Détermination calorimétrique isotherme (ISO 21911-1:2022)
Ta slovenski standard je istoveten z: prEN ISO 21911-1
ICS:
75.160.10 Trda goriva Solid fuels
oSIST prEN ISO 21911-1:2023 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 21911-1:2023

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oSIST prEN ISO 21911-1:2023
INTERNATIONAL ISO
STANDARD 21911-1
First edition
2022-11
Solid recovered fuels — Determination
of self-heating —
Part 1:
Isothermal calorimetry
Combustibles solides de récupération — Détermination de l'auto-
échauffement —
Partie 1: Détermination calorimétrique isotherme
Reference number
ISO 21911-1:2022(E)
© ISO 2022

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oSIST prEN ISO 21911-1:2023
ISO 21911-1:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
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oSIST prEN ISO 21911-1:2023
ISO 21911-1:2022(E)
Contents Page
Foreword .iv
Introduction .v
1 S c op e . 1
2 Nor m at i ve r ef er enc e s . 1
3 Terms and definitions . 1
4 P r i nc iple . 2
5 A pp a r at u s . 2
6 S a mple ha nd l i n g .3
6.1 General . 3
6 . 2 S a mpl in g . 4
6.3 S ample transport and storage . 4
6 .4 S a mple pr ep a r at ion . 4
7 Te s t pr o c e du r e .4
7.1 Temp er at u r e s t abi l i z at ion . . 4
7.2 S ample vial preparation . 4
7. 2 .1 P r ep a r at ion pr o c e du r e . 4
7.2.2 Procedure to find proper test portion in case of influence from oxygen
deficiency . 5
7.3 R eference vial preparation . 5
7.4 Me a s u r ement . 6
7.4.1 F irst baseline measurement . 6
7.4 . 2 S a mple me a s u r ement . 6
7.4.3 Second baseline measurement . 6
7.4.4 M easurement data file . 6
8 R e s u lt s . . 6
8 .1 Te s t d at a . 6
8 . 2 R ep or t e d d at a . 7
9 Te s t r ep or t . 7
Annex A (normative) Calibration of the calorimeter . 8
Annex B (informative) Example of isothermal calorimetric measurements of solid
recovered fuel .10
Bibliography .12
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oSIST prEN ISO 21911-1:2023
ISO 21911-1:2022(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 300, Solid recovered materials, including
solid recovered fuels.
A list of all parts in the ISO 21911 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
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oSIST prEN ISO 21911-1:2023
ISO 21911-1:2022(E)
Introduction
There is a continuous global growth in the trading and use of solid recovered fuels (SRFs). This has
resulted in an increased probability of fires, which has consequences for the handling, transporting
and storage of SRFs.
SRFs can generate heat spontaneously by exothermic biological, chemical and physical processes. The
heat build-up can be significant in large storage volumes if the heat conduction in the material is low. In
some conditions the heat generation can lead to pyrolysis and spontaneous ignition. The potential for
self-heating varies considerably for different types and qualities of SRFs and it is important to be able to
identify SRF fractions with high heat generation potential to avoid fires in stored materials.
The increasing number of incidents is a clear indicator that safety needs to be prioritized, first of all
for human safety and environmental concerns but also because interruptions in energy supply will
have significant consequences. SRF fires throughout the supply chain will also, in addition to safety and
environmental issues and direct economic losses, have a negative impact on the confidence in the SRFs
as a reliable energy source. They can also lead to difficulties in obtaining insurance coverage.
It is difficult for SRF producers, logistics providers, SRF users, equipment suppliers and manufacturers,
consultants, authorities and insurance providers to determine reasonable safety measures and an
appropriate level of protection due to a lack of standards and recommendations.
As part of the determination and the assessment of risks for SRFs, defined test methods and standards
are established or need to be developed. However, ageing and degradation due to the handling and
storage of SRFs in actual environments affects their characteristics, so safety margins should be
established in relation to actual analysis results.
The test method described in this document, isothermal calorimetry, is a method where the heat flow
generated from the test portion is measured directly. The operating temperature for an isothermal
calorimeter is normally in the range of 5 °C to 90 °C (some calorimeters can reach even higher
temperatures) and can therefore measure low-temperature reactions, such as those from bacteria and
other microbes. However, isothermal calorimetry is used for monitoring the thermal activity or heat
flow of chemical, physical and biological processes. The technique is most commonly used in the fields
of pharmaceuticals, energetic materials and cement. Isothermal calorimetry has also been applied for
[6]–[10]
the measurement of heat flow from the self-heating of solid biofuel pellets .
For investigating heat generation at high temperatures, other types of test methods, such as basket
heating tests, are possibly more suitable.
Data on spontaneous heat generation determined using this document are only associated with the
specific quality, composition and age of the sample material.
The information derived using this document is for use in quality control and in hazard and risk
assessments.
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oSIST prEN ISO 21911-1:2023

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oSIST prEN ISO 21911-1:2023
INTERNATIONAL STANDARD ISO 21911-1:2022(E)
Solid recovered fuels — Determination of self-heating —
Part 1:
Isothermal calorimetry
1 S cope
This document specifies an analytical method for quantification of the spontaneous heat generation
from solid recovered fuels using isothermal calorimetry.
This document gives guidance on the applicability and use of the specified analytical method. It further
establishes procedures for sampling and sample handling of solid recovered fuels prior to the analysis
of spontaneous heat generation.
The test procedure given in this document quantifies the thermal power (heat flow) of the sample
during the test. It does not identify the source of self-heating in the test portion analysed.
2 Normat ive references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 21637, Solid recovered fuels — Vocabulary
ISO 21645, Solid recovered fuels — Methods for sampling
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 21637 apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
analysis temperature
temperature of the analysis environment, i.e. the calorimeter temperature
3.2
self-heating
rise in temperature in a material resulting from an exothermic reaction within the material
[SOURCE: ISO 13943:2017, 3.341, modified — “” removed from the definition.]
3.3
test portion
sub-sample of either a laboratory sample (3.5) or a test sample (3.4) required for the specific
measurement
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oSIST prEN ISO 21911-1:2023
ISO 21911-1:2022(E)
3.4
test sample
laboratory sample (3.5) after an appropriate preparation made by the laboratory
3.5
laboratory sample
part of the sample sent to or received by the laboratory
3.6
thermal power
rate of heat flow produced by the sample during the test
Note 1 to entry: Expressed in W or J/s.
Note 2 to entry: Commonly also expressed as specific thermal power with reference to the unit mass of solid
recovered fuel in W/g or J/(s·g).
4 Principle
Isothermal calorimetry is one of the sensitive techniques for studying heat production or heat
consumption from samples of different kinds. It is non-destructive and non-invasive to the sample. Heat
production due to any physical, chemical or biological changes in a sample can be measured. When heat
is produced or consumed by any process, a temperature gradient is developed across the sensor. This
will generate a voltage, which is proportional to the heat flow across the sensor and to the rate of the
process taking place in the sample ampoule. The signal is recorded continuously and in real time.
NOTE 1 A commercial instrument for isothermal calorimetry normally has multiple channels and can thus be
used for measurements of several samples simultaneously.
For each sample (channel) there is an inert reference that is on a parallel heat-flow sensor. During
the time that the heat flow is monitored, any temperature fluctuations entering the instrument will
influence both the sample and the reference sensors equally. This architecture allows a very accurate
determination of heat that is produced or consumed by the sample alone while other non-sample-
related heat disturbances are efficiently removed. The measured heat flow is normalized against the
mass of the sample and the result is expressed in mW/g.
NOTE 2 The operating temperature for an isothermal calorimeter is typically in the range of 5 °C to 90 °C.
However, there are calorimeters with a somewhat higher span for operating temperature.
5 Apparatus
The usual laboratory apparatus and, in particular, the following shall be used.
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oSIST prEN ISO 21911-1:2023
ISO 21911-1:2022(E)
5.1 Isothermal calorimeter, consisting of a sample holder for the sample vial and the reference
vial, each thermally connected to heat-flow sensors, which are thermally connected to a constant
temperature sink. See example in Figure 1.
Key
1 thermostat 4 reference
2 heat sink 5 heat-flow sensors
3 sample
Figure 1 — Schematic drawing of an isothermal calorimeter
The calorimeter shall be calibrated for the analysis temperature according to Annex A, Clauses A.1, A.2
and A.3. The analysis temperatures for the screening test procedure are 50 °C and 70 °C.
The data acquisition equipment shall be capable of performing continuous logging of the calorimeter
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