EN ISO 18847:2024

SLOVENSKI STANDARD
01-julij-2024
Nadomešča:
SIST EN ISO 18847:2016
Trdna biogoriva - Določevanje gostote delcev peletov in briketov (ISO 18847:2024)
Solid biofuels - Determination of particle density of pellets and briquettes (ISO
18847:2024)
Biogene Festbrennstoffe - Bestimmung der Partikeldichte von Pellets und Briketts (ISO
18847:2024)
Biocombustibles solides - Détermination de la masse volumique unitaire des granulés et
des briquettes (ISO 18847:2024)
Ta slovenski standard je istoveten z: EN ISO 18847:2024
ICS:
17.060 Merjenje prostornine, mase, Measurement of volume,
gostote, viskoznosti mass, density, viscosity
27.190 Biološki viri in drugi Biological sources and
alternativni viri energije alternative sources of energy
75.160.40 Biogoriva Biofuels
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 18847
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2024
EUROPÄISCHE NORM
ICS 27.190; 75.160.40 Supersedes EN ISO 18847:2016
English Version
Solid biofuels - Determination of particle density of pellets
and briquettes (ISO 18847:2024)
Biocombustibles solides - Détermination de la masse Biogene Festbrennstoffe - Bestimmung der
volumique unitaire des granulés et des briquettes (ISO Partikeldichte von Pellets und Briketts (ISO
18847:2024) 18847:2024)
This European Standard was approved by CEN on 20 April 2024.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 18847:2024 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 18847:2024) has been prepared by Technical Committee ISO/TC 238 "Solid
biofuels" in collaboration with Technical Committee CEN/TC 335 “Solid biofuels” the secretariat of
which is held by SIS.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by November 2024, and conflicting national standards
shall be withdrawn at the latest by November 2024.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 18847:2016.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 18847:2024 has been approved by CEN as EN ISO 18847:2024 without any modification.

International
Standard
ISO 18847
Second edition
Solid biofuels — Determination
2024-04
of particle density of pellets and
briquettes
Biocombustibles solides — Détermination de la masse volumique
unitaire des granulés et des briquettes
Reference number
ISO 18847:2024(en) © ISO 2024
ISO 18847:2024(en)
© ISO 2024
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: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 18847:2024(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Reagents . 1
6 Apparatus . 2
6.1 General apparatus requirements .2
6.2 Apparatus for pellet testing .2
6.3 Apparatus for briquette testing .3
7 Sample preparation . 4
7.1 General apparatus requirements .4
8 Procedures . 5
8.1 Procedure for pellets .5
8.2 Procedure for briquettes .6
9 Calculation . 6
10 Performance characteristics . 7
10.1 General .7
10.2 Repeatability .7
10.3 Reproducibility . .7
11 Test report . 7
Annex A (informative) Stereometric volume estimation . 8
Annex B (informative) Estimation of the particle density of pellets by liquid displacement .12
Bibliography . 14

iii
ISO 18847:2024(en)
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 document 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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
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 238, Solid biofuels, in collaboration with
the European Committee for Standardization (CEN) Technical Committee CEN/TC 335, Solid biofuels, in
accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 18847:2016), which has been technically
revised.
The main changes are as follows:
— editorial changes made;
— ISO 21945 inserted as a normative reference;
— method for the determination of particle density is specified in more detail;
— informative Annex B on a liquid displacement method to estimate the particle density of pellets added.
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.

iv
ISO 18847:2024(en)
Introduction
Particle density is a fuel parameter of pellets and briquettes which is often considered when describing the
degree of compaction of the raw material used. Particle density can be highly specific for the respective
type or species of biomass and thus, it also characterizes the material's general ability to be compacted.
High particle density is often associated with high resistance to abrasion or low susceptibility towards
fracturing during handling and storage. A high particle density also generally leads to reduced storage
volume demands and to a lower filling level in a combustion chamber at constant fuel mass flow. Particle
density can also affect the heat transfer rate within the fuel and thus, it can have an impact on fuel ignition
and on the dynamics of gasification.
Apart from the buoyancy method which is described in this document as a reference method, larger
particles (briquettes) are sometimes easier tested by simple stereometric means. For internal laboratory
practices, such a procedure is also presented in Annex A. For small particles (pellets), this procedure is not
recommended.
For pellets, a simplified method using the displacement of a liquid by the pellets is available, which can be
used as an on-site method, and is described in Annex B.
Pellets disintegrate in water relatively fast, but with the buoyancy method the particle density is sufficiently
stable for about 30 s (see [3]). To improve reproducibility, the reading of the results is fixed at 5 s. This also
ensures synchronization with the results of the estimation method by liquid displacement.
For the determination of particle density, several other methods are available. Normally the results show
only minor deviations.
v
International Standard ISO 18847:2024(en)
Solid biofuels — Determination of particle density of pellets
and briquettes
1 Scope
This document specifies a method for determining the particle density of compressed fuels such as pellets
or briquettes. Particle density is not an absolute value and conditions for its determination have to be
standardized to enable comparative determinations to be made.
2 Normative 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 14780, Solid biofuels — Sample preparation
ISO 16559, Solid biofuels — Vocabulary
ISO 18135, Solid Biofuels — Sampling
ISO 21945, Solid biofuels — Simplified sampling method for small scale applications
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 16559 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/
4 Principle
Both mass and volume of an individual particle or a group of particles are determined. The volume is
measured by determining the buoyancy in a liquid. This procedure follows the physical principle that the
buoyancy is equal to the mass of the displaced volume of a liquid. The apparent loss in weight between a
measurement in air and a subsequent measurement in liquid marks its buoyancy. The volume of the test
portion body is calculated via the density of the applied liquid.
NOTE 1 The particle density of briquettes can alternatively be estimated by stereometric means (see Annex A).
NOTE 2 As an on-site method the particle density of pellets can be estimated by a displacement method (see
Annex B).
5 Reagents
5.1 Water, with a conductivity < 1 000 µS/cm (e.g. typical drinking water quality) in a temperature range
of 10 °C to 30 °C.
ISO 18847:2024(en)
5.2 Detergent. A non-ionic surfactant detergent named O-[4-(1,1,3,3-Tetramethylbutyl)-phenyl]-
deca(oxyethylen), Octylphenoldecaethylen-glycolether, Polyethylenglycol-mono-[p-(1,1,3,3-
tetramethylbutyl)-phenyl]-ether. Alternatively, a non-ionic surfactant with similar properties may be used,
e. g. Ethylene oxide-propylene oxide copolymer mono(2-ethylhexyl) ether.
Using an alternative detergent, the density of the liquid used for the determination (water with 1, 5 g/l
detergent) shall be determined to the nearest 0,001 g/l and used for calculations instead of the value given
in Clause 9.
NOTE The exclusive use of a specific detergent with given characteristics allows to apply a fixed value for the
density of the liquid (mixture with water) and ensures constant properties as wetting agent. As an example, the
1)
detergent available under the name Triton® X-100 can be used. The density at +20 °C is 1,07 g/ml. According to
health and/or environmental regulations, the use of an alternative detergent can be necessary.
5.3 Paraffin, with a melting point of 52 °C to 54 °C.
6 Apparatus
6.1 General apparatus requirements
A thermometer capable of reading to the nearest 1 °C.
6.2 Apparatus for pellet testing
6.2.1 Balance, shall be capable of reading to the nearest 0,001 g.
6.2.2 Glass beaker, a transparent glass beaker with
...