SIST EN ISO 17225-4:2021

Solid biofuels - Fuel specifications and classes - Part 4: Graded wood chips (ISO 17225-4:2021)

This document determines the fuel quality classes and specifications of graded wood chips. This document covers only wood chips produced from the following raw materials (see ISO 17225-1:2021, Table 1):
1.1 Forest, plantation and other virgin wood;
1.2 By-products and residues from wood processing industry;
1.3.1 Chemically untreated used wood.
This document covers only wood chips, which are produced with sharp tools, and does not cover hog fuel, which is produced with blunt tools.

Biogene Festbrennstoffe - Brennstoffspezifikationen und -klassen - Teil 4: Klassifizierung von Holzhackschnitzel (ISO 17225-4:2021)

Dieses Dokument legt die qualitätsbezogenen Brennstoffklassen und  spezifikationen für klassifizierte Holz¬hackschnitzel fest. Dieses Dokument umfasst nur Holzhackschnitzel, die aus folgenden Rohmaterialien her¬gestellt wurden (siehe ISO 17225 1:2021, Tabelle 1):
- 1.1 Wald- und Plantagenholz sowie anderes naturbelassenes Holz;
- 1.2 Industrie-Restholz;
- 1.3.1 Chemisch unbehandeltes Gebrauchtholz.
Dieses Dokument behandelt nur Holzhackschnitzel, die mithilfe von scharfen Werkzeugen hergestellt wurden, und behandelt kein Schredderholz, das mithilfe von stumpfen Werkzeugen hergestellt wurde.

Biocombustibles solides - Classes et spécifications des combustibles - Partie 4: Classes de plaquettes de bois (ISO 17225-4:2021)

Le présent document détermine les classes et spécifications de qualité du combustible pour des plaquettes de bois. Le présent document couvre uniquement les plaquettes de bois produites à partir des matières premières suivantes (voir ISO 17225-1:2021, Tableau 1):
1.1 bois de forêt, de plantation et autres matériaux ligneux vierges;
1.2 produits dérivés et sous-produits de l'industrie de transformation du bois;
1.3.1 bois usagé non traité chimiquement.
Le présent document ne couvre que les plaquettes de bois produites à l'aide d'outils tranchants; elle ne couvre pas le combustible bois broyé produit à l'aide d'outils non tranchants.

Trdna biogoriva - Specifikacije goriv in razredi - 4. del: Razvrstitev lesnih sekancev (ISO 17225-4:2021)

General Information

• Status: Published
• Public Enquiry End Date: 03-May-2020
• Publication Date: 15-Apr-2021
• ICS: 75.160.40 - Biofuels
• Technical Committee: AGO - Refuse derived fuel
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 24-Mar-2021
• Due Date: 29-May-2021
• Completion Date: 16-Apr-2021
• Directive: 2014-01-4040 - Uredba o predelavi nenevarnih odpadkov v trdno gorivo in njegovi uporabi
• Directive: 2019-01-2272 - Uredba o emisiji snovi v zrak iz malih kurilnih naprav
• Ref Project: EN ISO 17225-4:2021 - Solid biofuels - Fuel specifications and classes - Part 4: Graded wood chips (ISO 17225-4:2021)

Relations

• Replaces: SIST EN ISO 17225-4:2014 - Solid biofuels - Fuel specifications and classes - Part 4: Graded wood chips (ISO 17225-4:2014)
• Effective Date: 01-May-2021

Overview

EN ISO 17225-4:2021 - Solid biofuels: Graded wood chips defines fuel quality classes and specifications for graded wood chips used as solid biofuel. Published by CEN and identical to ISO 17225-4:2021, this part of the ISO 17225 series covers wood chips produced with sharp tools from the following raw materials:

• forest, plantation and other virgin wood;
• by‑products and residues from the wood processing industry;
• chemically untreated used wood.

The standard explicitly excludes hog fuel (produced with blunt tools) and gives guidance to support trading, equipment compatibility and regulatory reporting for residential, commercial and small/medium industrial heating applications.

Key topics and technical requirements

• Fuel quality classes - Defines property classes (e.g., A1, A2, B1, B2) that group fuels by origin and typical quality (A classes for virgin/untreated residues; B classes extend to more diverse or partly treated sources).
• Particle size and grading - Updated particle size distribution classification to ensure compatibility with conversion equipment. The standard references ISO 17827‑1 (oscillating screen method) for particle sizing.
• Moisture, ash and chemical properties - Moisture and ash content classes updated in this edition; chemical contaminants (e.g., heavy metals, halogenated organics) are addressed when raw material suspicion exists. Relevant test methods are cited (ISO 18134‑2 for moisture, ISO 18122/18135 for ash and sampling).
• Sampling and analysis - Sampling and sample preparation must follow ISO 18135/ISO 21945 and ISO 14780 to ensure representative test results.
• Bulk density guidance - Informative Annex A provides general guidelines for bulk density of graded wood chips (loose volume).
• Traceability and declaration - Requirements for declaring raw material origin (especially for chemically treated sources) and for performing additional analyses when contamination is suspected.

Applications and users

EN ISO 17225-4:2021 is intended for:

• Fuel suppliers and traders specifying and selling graded wood chips.
• Boiler and gasifier manufacturers checking fuel compatibility and designing feed systems.
• Facility managers and heating contractors selecting appropriate fuel for residential, commercial and public building installations.
• Testing laboratories and certification bodies performing sampling and analysis.
• Regulators and procurement teams requiring standardized fuel specifications for permits and public procurement.

Typical application scales noted in the standard range from below 100 kW (residential) up to several MW (small/medium district heating and commercial systems).

Related standards

• ISO 17225‑1 (General requirements) - recommended to use in conjunction with Part 4.
• ISO 14780, ISO 16559, ISO 16948, ISO 16994, ISO 17827‑1, ISO 18122, ISO 18134‑2, ISO 18135, ISO 21945 - normative references for sampling and analysis.
• EN 303‑5 - boilers testing reference for residential applications.

Keywords: EN ISO 17225-4:2021, graded wood chips, solid biofuels, fuel specifications, wood chip quality classes, moisture content, particle size, bulk density, ash content, sampling and analysis.

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2021
Nadomešča:
SIST EN ISO 17225-4:2014
Trdna biogoriva - Specifikacije goriv in razredi - 4. del: Razvrstitev lesnih sekancev
(ISO 17225-4:2021)
Solid biofuels - Fuel specifications and classes - Part 4: Graded wood chips (ISO 17225-
4:2021)
Biogene Festbrennstoffe - Brennstoffspezifikationen und -klassen - Teil 4: Klassifizierung
von Holzhackschnitzel (ISO 17225-4:2021)
Biocombustibles solides - Classes et spécifications des combustibles - Partie 4: Classes
de plaquettes de bois (ISO 17225-4:2021)
Ta slovenski standard je istoveten z: EN ISO 17225-4:2021
ICS:
75.160.40 Biogoriva Biofuels
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 17225-4
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2021
EUROPÄISCHE NORM
ICS 27.190; 75.160.40 Supersedes EN ISO 17225-4:2014
English Version
Solid biofuels - Fuel specifications and classes - Part 4:
Graded wood chips (ISO 17225-4:2021)
Biocombustibles solides - Classes et spécifications des Biogene Festbrennstoffe - Brennstoffspezifikationen
combustibles - Partie 4: Classes de plaquettes de bois und -klassen - Teil 4: Klassifizierung von
(ISO 17225-4:2021) Holzhackschnitzel (ISO 17225-4:2021)
This European Standard was approved by CEN on 8 January 2021.

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, Turkey 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
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 17225-4:2021 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 17225-4:2021) 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 September 2021, and conflicting national standards
shall be withdrawn at the latest by September 2021.
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 17225-4:2014.
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, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 17225-4:2021 has been approved by CEN as EN ISO 17225-4:2021 without any
modification.
INTERNATIONAL ISO
STANDARD 17225-4
Second edition
2021-02
Solid biofuels — Fuel specifications
and classes —
Part 4:
Graded wood chips
Biocombustibles solides — Classes et spécifications des
combustibles —
Partie 4: Classes de plaquettes de bois
Reference number
ISO 17225-4:2021(E)
©
ISO 2021
ISO 17225-4:2021(E)
© ISO 2021
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
ii © ISO 2021 – All rights reserved

ISO 17225-4:2021(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 2
5 Specification of graded wood chips. 3
Annex A (informative) General guidelines for bulk density of graded wood chips .7
Bibliography . 8
ISO 17225-4:2021(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 TC238, Solid biofuels.
This second edition cancels and replaces the first edition (ISO 17225-4:2014), which has been technically
revised. The main changes compared to the previous edition are as follows:
— particle size distribution classification updated;
— moisture and ash content classes updated;
— Annex A updated.
A list of all parts in the ISO 17225 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.
iv © ISO 2021 – All rights reserved

ISO 17225-4:2021(E)
Introduction
The objective of the ISO 17225 series is to provide unambiguous and clear classification principles for
solid biofuels; to serve as a tool to enable efficient trading of solid biofuels; to enable good understanding
between seller and buyer as well as a tool for communication with equipment manufacturers. It also
[2]
facilitates authority permission procedures and reporting .
This document supports the use of graded wood chips for small and medium residential, commercial
and public building applications.
Depending on the type of energy conversion technology used (boilers, heaters, gasifiers, etc., the
tolerances for a particular quality of wood chips will be different.
Scales of applications and their typical operation range:
- below 100 kW (Residential);
- from 75 to 500 kW (Small; e.g. residential, public and commercial buildings);
- from 500 kW to 1,5 MW (Medium; public and commercial buildings);
- 1,5 MW to 5 MW (Large; small industrial facilities and district heating);
1)
- over 5 MW (Industrial; recommended to use 'ISO 17225-1 or ISO/DIS 17225-9 )
The scale used for grouping the applications utilizing wood chips is for illustration only and in practice,
some overlaps between the applications and the scales are expected.
The residential, small and medium commercial and public building applications require high quality
fuel for the following reasons:
• Small-scale equipment usually does not have advanced controls and flue gas cleaning.
• Appliances are not generally managed by professional heating engineers.
• Appliances are often located in residential and populated districts.
[1]
NOTE 1 Wood chips produced according to this document can be used in boilers tested according to EN 303–5 .
NOTE 2 For individual contracts and industrial use, ISO 17225-1 or ISO/DIS 17225-9 can be used.
Although this document can be obtained separately, it requires a general understanding of the
standards based on and supporting ISO 17225-1. It is recommended to obtain and use ISO 17225-1 in
conjunction with this document.
1) Under preparation. Stage at the time of publication: ISO/DIS 17225-9:2021.
INTERNATIONAL STANDARD ISO 17225-4:2021(E)
Solid biofuels — Fuel specifications and classes —
Part 4:
Graded wood chips
1 Scope
This document determines the fuel quality classes and specifications of graded wood chips. This
document covers only wood chips produced from the following raw materials (see ISO 17225-1:2021,
Table 1):
• 1.1 Forest, plantation and other virgin wood;
• 1.2 By-products and residues from wood processing industry;
• 1.3.1 Chemically untreated used wood.
This document covers only wood chips, which are produced with sharp tools, and does not cover hog
fuel, which is produced with blunt tools.
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 — Terminology, definitions and descriptions
ISO 16948, Solid biofuels — Determination of total content of carbon, hydrogen and nitrogen
ISO 16968, Solid biofuels — Determination of minor elements
ISO 16994, Solid biofuels — Determination of total content of sulfur and chlorine
ISO 17225-1, Solid biofuels — Fuel specifications and classes — Part 1: General requirements
ISO 17827-1, Solid biofuels — Determi
...