ISO 17225-8

Solid biofuels — Fuel specifications and classes — Part 8: Graded thermally treated and densified biomass fuels for commercial and industrial use

This document determines the fuel quality classes and specifications of graded densified solid biofuels produced from thermally treated biomass for commercial applications and industrial use. This document covers pellets and briquettes produced from the following raw materials (see ISO 17225‑1:2021, Table 1): — woody biomass; — herbaceous biomass; — fruit biomass; — aquatic biomass; — blends and mixtures. Subcategories of these raw materials are included. This document does not consider products which are marketed as charcoal or as charcoal products. For these products, see ISO 17225‑1:2021, Table 14. NOTE Health, safety and environmental issues for solid biofuels are important and need special attention; however, they are outside the scope of this document.

Biocombustibles solides — Classes et spécifications des combustibles — Partie 8: Combustibles de biomasses traitées thermiquement et densifiées en vue d'une utilisation commerciale et industrielle

Le présent document détermine les classes de qualité des combustibles et les spécifications des classes de biocombustibles solides densifiés produits à partir de biomasses traitées thermiquement en vue d'une application commerciale et utilisation industrielle. Le présent document traite des granulés et des briquettes produits à partir des matières premières suivantes (voir l'ISO 17225‑1:2021, Tableau 1): — biomasse ligneuse; — biomasse herbacée; — biomasse fruitière; — biomasse aquatique; — assortiments et mélanges. Les sous-catégories de ces matières premières sont incluses. Le présent document ne prend pas en compte les produits commercialisés sous forme de charbon de bois ou de produits à base de charbon de bois. Pour de tels produits, voir l'ISO 17225‑1:2021, Tableau 14. NOTE Les questions de santé, de sécurité et d'environnement concernant les biocombustibles solides sont importantes et nécessitent une attention particulière; toutefois, elles ne relèvent pas du domaine d'application du présent document.

General Information

• Status: Not Published
• ICS: 27.190 - Biological sources and alternative sources of energy
• ICS: 75.160.40 - Biofuels
• Technical Committee: ISO/TC 238 - Solid biofuels
• Drafting Committee: ISO/TC 238 - Solid biofuels
• Current Stage: 6000 - International Standard under publication
• Completion Date: 27-Jan-2023

Relations

• Revises: ISO/TS 17225-8:2016 - Solid biofuels — Fuel specifications and classes — Part 8: Graded thermally treated and densified biomass fuels
• Effective Date: 06-Jun-2022
• Consolidates: ISO 2426-2:2020 - Plywood — Classification by surface appearance — Part 2: Hardwood
• Effective Date: 06-Jun-2022

Standards Content (Sample)

2022-07-0511-04
ISO/DISFDIS 17225-8:2022(E)
ISO TC 238
Secretariat: SIS

Solid biofuels — Fuel specifications and classes — Part 8: Graded thermally treated and

densified biomass fuels for commercial and industrial use

Biocombustibles solides — Classes et specificationsspécifications des combustibles — Partie 8:

Combustibles de biomasses traitées thermiquement et densifiées en vue d'une utilisation

commerciale et industrielle
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ISO/DISFDIS 17225-8:2022(E)
© 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
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Website: www.iso.orgwww.iso.org
Published in Switzerland
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ISO/DISFDIS 17225-8:2022(E)
Contents

Foreword ......................................................................................................................................................................... iv

Introduction..................................................................................................................................................................... v

1 Scope .................................................................................................................................................................... 1

2 Normative references .................................................................................................................................... 1

3 Terms and definitions .................................................................................................................................... 2

4 Symbols and abbreviated terms ................................................................................................................ 3

5 Specification of graded pellets and briquettes produced by thermal processing ................... 4

Annex A (normative) Template for classification of densified and non-densified biomass

fuels produced by thermal processing ................................................................................................. 13

Annex B (informative) Reference values for the calculation of the limit values on energy

basis ................................................................................................................................................................... 15

Bibliography ................................................................................................................................................................. 17

Foreword ......................................................................................................................................................................... iv

Introduction..................................................................................................................................................................... v

1 Scope .................................................................................................................................................................... 1

2 Normative references .................................................................................................................................... 1

3 Terms and definitions .................................................................................................................................... 2

4 Symbols and abbreviated terms ................................................................................................................ 3

5 Specification of graded pellets and briquettes produced by thermal processing ................... 4

Annex A (normative) Template for classification of densified and non-densified biomass

fuels produced by thermal processing ................................................................................................. 13

Annex B (informative) Reference values for the calculation of the limit values on energy

basis ................................................................................................................................................................... 15

Bibliography ................................................................................................................................................................. 17

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ISO/DISFDIS 17225-8:2022(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/directiveswww.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/patentswww.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.htmlwww.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 documentfirst edition cancels and replaces the first edition (ISO/TS 17225-8:2016,), which has been

technically revised.
The main changes are as follows:
— raw material basis enlarged;

— Tables 1 to 6 merged into Tables 1 to 3, to be used for pellets and briquettes;

— table for thermally treated woody biomass split in two tables (Table 1 and Table 2);

— threshold values for Tables 1 to 3 stated in terms of energy;
— Annex A introduced to support product specification;

— Annex B introduced to support the calculation of the limit values in terms of energy.

A list of all parts in the ISO 17225 series can be found on the ISO website.
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ISO/DISFDIS 17225-8:2022(E)

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.htmlwww.iso.org/members.html.
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ISO/DISFDIS 17225-8:2022(E)
Introduction

The objective of this document is to provide unambiguous and clear classification principles for solid

biofuels, to serve as a tool, to enable efficient trading of biofuels, to enable good understanding between

seller and buyer as well as to serve as a tool for communication with equipment manufacturers. It will

also facilitate legal permission procedures and reporting.

This document supports the use of thermally treated and densified biomass in commercial and industrial

energy generation applications and in industrial processes, which require classified quality.

Thermal treatment includes processes such as torrefaction, steam explosion, hydrothermal carbonization

and charring, all of which represent different exposure to heat, oxygen, steam or water. Thermally treated

and densified biomass fuels should only be used in plants with manufacturer approval.

For individual contracts, ISO 17225-1 can be used. ISO 17225-1 can also be used for specification of

charcoal.

Although this document may be used separately, a general understanding of the standards based on and

supporting ISO 17225-1 is required. It is recommended that ISO 17225-1 is used in conjunction with this

document.
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FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 17225-8:2022(E)
Solid biofuels — Fuel specifications and classes — Part 8:
Graded thermally treated and densified biomass fuels for
commercial and industrial use
1 Scope

This document determines the fuel quality classes and specifications of graded densified solid biofuels

produced from thermally treated biomass for commercial use and industrial use. This document covers

pellets and briquettes produced from the following raw materials (see ISO 17225-1:2021, Table 1):

— woody biomass;
— herbaceous biomass;
— fruit biomass;
— aquatic biomass;
— blends and mixtures.
Subcategories of these raw materials are included.

This document does not consider products which are marketed as charcoal or as charcoal products. For

these products, see ISO 17225-1:2021, Table 14.

NOTE Health, safety and environmental issues for solid biofuels are important and need special attention;

however, they are outside the scope of this document.
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 5370, Solid biofuels — Determination of fines content in pellets
ISO 14780, Solid biofuels — Sample preparation
ISO 16559, Solid biofuels — Vocabulary

ISO 16948, Solid biofuels — Determination of total content of carbon, hydrogen and nitrogen

ISO 16968, Solid biofuels — Determination of minor elements
Formatted: Footnote Text, Left, Space Before: 0 pt,
After: 0 pt
Under preparation. Stage at the time of publication: ISO/DIS 5370:2022.
Formatted: Font: 10 pt, Font color: Auto
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ISO/FDIS 17225-8:2022(E)

ISO 16994, Solid biofuels — Determination of total content of sulfur and chlorine

ISO 17225-1:2021, Solid biofuels — Fuel specifications and classes — Part 1: General requirements

ISO 17828, Solid biofuels — Determination of bulk density
ISO 17829, Solid Biofuels — Determination of length and diameter of pellets

ISO 17831-1, Solid biofuels — Determination of mechanical durability of pellets and briquettes — Part 1:

Pellets

ISO 17831-2, Solid biofuels — Determination of mechanical durability of pellets and briquettes — Part 2:

Briquettes
ISO 18122, Solid biofuels — Determination of ash content
ISO 18125, Solid biofuels — Determination of calorific value

ISO 18134-1, Solid biofuels — Determination of moisture content — Oven dry method — Part 1: Total

moisture — Reference method

ISO 18134-2, Solid biofuels — Determination of moisture content — Oven dry method — Part 2: Total

moisture — Simplified method
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 and the following 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
pellets made from thermally treated biomass

densified biofuel made from thermally treated solid biomass with or without additives usually with a

cylindrical form, random length typically 5 mm to 40 mm, diameter up to 25 mm and broken ends

EXAMPLE Torrefied biomass, steam exploded biomass, hydrothermally carbonized biomass, charred biomass.

Note 1 to entry: Drying is not considered as thermal treatment in this definition.

Note 2 to entry: Fuel pellets which are produced by applying the thermal treatment after densification are also

included in this definition.
3.2
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ISO/FDIS 17225-8:2022(E)
briquettes made from thermally treated biomass

densified biofuel made with or without additives in pre-determined geometric form with at least two

dimensions (height width, and length) of more than 25 mm produced by compressing thermally treated

solid biomass

EXAMPLE Torrefied biomass, steam exploded biomass, hydrothermally carbonized biomass, charred biomass.

Note 1 to entry: Drying is not considered as thermal treatment in this definition.

Note 2 to entry: Fuel briquettes which are produced by applying the thermal treatment after densification are also

included in this definition.
3.3
commercial applicationuse

facility that utilizes solid biofuel burning appliances or equipment that have similar fuel requirements as

residential appliances

Note 1 to entry: Commercial applications should not be confused with industrial applications, which can utilize a

much wider array of materials and have vastly different fuel requirements.
[SOURCE: ISO 17225-1:2021, 3.2]
3.4
post-immersion durability reduction
DUR

measure of the drop in the durability of thermally treated biomass fuel pellets after immersion in water

Note 1 to entry: A post-immersion durability reduction value of 0 means there was no change to the durability of

the thermally treated pelletized fuel as a result of wetting, whereas, for example, a post-immersion durability

reduction value of 3 indicates that the durability dropped by three percentage points as a result of wetting.

Note 2 to entry: The test procedure is given in ISO 23343-1.

[SOURCE: ISO 23343-1:2021, 3.2, modified — Definition revised and Note 2 to entry added.]

3.5
thermally treated biomass

biomass whose chemical composition has been changed by heat (usually by temperatures of 200 °C to

300 °C and above)
3.6
thermally treated biomass grindability index
TTBGI

measure for the tendency of a fixed volume of thermally treated biomass material to produce fine

particles after grinding under defined settings and conditions
[SOURCE: ISO/TS 21596:2021, 3.3]
3.7
water sorption
SORP
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ISO/FDIS 17225-8:2022(E)

gain or loss of water or moisture by solid biofuels through absorption or adsorption when exposed to

water or varying levels of humidity
[SOURCE: ISO 16559:2022, 3.216]
4 Symbols and abbreviated terms
A designation for ash content on a dry basis [g/MJ dry]
ar as received
BD designation for bulk density as received [kg/m , (loose volume)]
C fixed carbon [% in mass dry]
D designation for diameter as received [mm]
d dry (dry basis)
DT designation for deformation temperature of the fuel ash [°C]
DU designation for mechanical durability as received [% in mass]
DURpi designation for post-immersion durability reduction [% in mass]
F designation for amount of fines (< 3,15 mm) as received [% in mass]
F0.5 designation for amount of fines below 0,5 mm as received [% in mass]
FT designation for flow temperature of the fuel ash [°C]
HT designation for hemisphere temperature of the fuel ash [°C]
L designation for length as received [mm]
M designation for moisture as received on a wet basis, M [% in mass]

Q designation for net calorific value as received, q [MJ/kg, GJ/t, kWh/kg or MWh/t]

p,net,ar
at constant pressure

Qd designation for net calorific value on a dry basis, qp,net,d [MJ/kg or GJ/t or kWh/kg or

MWh/t] at constant pressure
SST designation for shrinkage starting temperature of the fuel ash [°C]
TTBGI thermally treated biomass grindability index [% in mass]
VM volatile matter on a dry basis [% in mass dry]
W water sorption [% in mass]
SORP

NOTE 1 1 MJ/kg equals 0,2 778 kWh/kg (1 kWh/kg equals 1 MWh/t and 1 MWh/t equals 3,6 MJ/kg). 1 g/cm

equals 1 kg/dm . 1 mg/kg equals 0,000 1 %.

NOTE 2 Designation symbols are used with a number to specify property levels in Tables 1 to 3 and Annex A. For

designation of chemical properties, chemical symbols such as S (sulfur), Cl (chlorine), N (nitrogen) and C (carbon)

are used and the property class is added at the end of the symbol. Values of ash content and chemical properties (N,

S, Cl, As, Cd, Cr, Cu, Pb, Hg, Ni and Zn) are given in g/MJ or mg/MJ, both on a dry basis, with the index MJ (e.g. SMJ).

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ISO/FDIS 17225-8:2022(E)
5 Specification of graded pellets and briquettes produced by thermal processing

Property classes of graded densified biomass fuels produced by thermal processing of chemically

untreated woody biomass, chemically untreated and/or chemically treated woody biomass and non-

woody biomass are listed in Tables 1, 2 and 3, respectively. If a densified biomass fuel produced by

thermal processing cannot be classified according to Table 1, 2 or 3, a specification shall be done

according to Annex A.

The specification of pellets made from thermally treated biomass is stated in accordance with Tables 1 to

3 and Figure 1, while briquettes made from thermally treated biomass are specified in accordance with

Tables 1 to 3 and Figure 2. If other traded forms are used, the main dimensions (e.g. height, width, length)

shall be stated.
Key
D diameter
L length
Figure 1 — Dimensions of pellets
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ISO/FDIS 17225-8:2022(E)
Key
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ISO/FDIS 17225-8:2022(E)
D diameter
L1 length
L2 width
L height
Figure 2 — Shapes and dimensions of briquettes

Sampling and sample preparation shall be done according to ISO 18135 or ISO 21945 and ISO 14780,

respectively. Analyses of the properties shall be carried out in accordance with the appropriate standard,

i.e. ISO 5370, ISO 16948, ISO 16968, ISO 16994, ISO 17828, ISO 17829, ISO 17831-1, ISO 17831-2,

ISO 18122, ISO 18125, ISO 18134-1, and ISO 18134-2. For specification of the origin and source,

ISO 17225-1 shall be applied.

If data for chemical or physical properties are available, further analysis may not be required.

To ensure resources are used appropriately and the declaration is accurate, use the most appropriate

measure as follows:
a) using previous measured values or experience of the same raw material;

b) calculation of properties, for example using typical values and considering generally accepted and

documented specific values;
c) carrying out analysis:
1) with simplified methods, if available;
2) with reference methods.

The responsibility of the producer or supplier to provide correct and accurate information is exactly the

same whether laboratory analysis is performed or not. Typical values do not release the producer or

supplier from providing accurate and reliable information.

To assign a fuel to a property class, all properties listed as normative parameter in Table 1, 2 and 3 as

well as Table A1 shall be determined. The determination of properties listed as informative parameter

is recommended. The classes of mechanical, physical and chemical properties shall be stated when

leaving the final point of loading for delivery to the end user. Between the factory gates and the end user,

distributors shall take appropriate measures to maintain the stated level of fines. The quality class

according to Table 1, Table 2, Table 3 or Table A.1 shall be given in the product declaration.

Ash content and concentration of chemical elements N, S, Cl, As, Cd, Cr, Cu, Pb, Hg, Ni and Zn are influenced

by thermal processing and shall be stated in terms of energy with the units g/MJ or mg/MJ (dry),

respectively. To calculate the unit mg/MJ from mg/kg, the concentration of chemical elements (mg/kg on

a dry basis) shall be divided by the net calorific value (Qd, MJ/kg on a dry basis). Values in percentage

mass (dry) shall be additionally multiplied by 10 to obtain values in g/MJ (dry). The reference values used

for the calculation of the normative limit values in terms of energy are listed in Annex B. In any analytical

report or product declaration, values shall be stated additionally in terms of mass (in mg/kg dry or %

mass dry). The values shall be rounded individually according to the significant digits of each property

specified in Table 1, 2 and 3.

NOTE 1 For a sample of thermally treated pellets with a lead content of 12 mg/kg dry and a calorific value of

19 MJ/kg dry the resulting value for PbMJ is 0,63 mg/MJ dry and exceeds the limit value of 0,53 mg/MJ dry for TW1.

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ISO/FDIS 17225-8:2022(E)

A sample with the same lead content of 12 mg/kg dry and a calorific value of 24,5 MJ/kg dry results in a value of

0,49 mg/MJ dry and fulfils the requirement of class TW1.

NOTE 2 According to ISO 17225-1:2021, Annex D, the net calorific value (at constant pressure) on a dry basis can

be calculated according to Formula (1).
100
q =�q +0,024 43×𝑀𝑀 � ×  (1)
p,net,d p,net,ar ar
100−𝑀𝑀
100
Field Code Changed
qq+ 0,024 43× M× (1)
p,net,d p,net,ar ar
100− M
where

q is the net calorific value (at constant pressure) as received, in megajoules per kilogram

p,net,ar
(MJ/kg);

qp,net,d is the net calorific value (at constant pressure) in dry matter, in megajoules per kilogram

(MJ/kg);
M is the moisture content as received in % mass;

0,024 43 is the correction factor of the enthalpy of vaporization (constant pressure) for water

(moisture) at 25 °C, in megajoules per kilogram (MJ/kg) per 1 % in mass of moisture.

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ISO/FDIS 17225-8:2022(E)

Table 1 — Specification of graded densified biomass fuels produced from thermally processed

chemically untreated woody biomass
Master table
Property
Unit TW1 TW2
(analysis method)
Normative Origin and source 1.1 Forest, plantation and other virgin wood
(ISO 17225-1:2021, 1.2.1 Chemically untreated wood by-products and
Table 1) residues
Traded form (see
ISO 17225-1:2021, Pellets or briquettes
Table 2)
Dimensions (mm) ISO 17829
Diameter (D) and D06, 6 ± ± 1; D06, 6 ± ± 1;
length (L) of pellets in mm D08, 8 ± ± 1; D08, 8 ± ± 1;
accordance with Figure 1 3,15 ≤ L ≤ ≤ 40 3,15 ≤ ≤ L ≤ ≤ 40
Diameter (D), length (L)
and shape of briquettes
mm Values to be stated
in accordance with
Figure 2
Moisture, M, % in mass as
ISO 18134-1, ISO 18134- received, on M08 ≤ 8 M08 ≤ 8
2 wet basis
Ash, AMJ, ISO 18122 g/MJ dry A0.6 ≤ 0,6 A1.6 ≤ 1,6
Mechanical durability
to be stated for pellets
and for briquettes with % in mass as
DU97.5 ≥ 97,5 DU97.5 ≥ 97,5
shape 9 (Figure 2), DU, received
ISO 17831-1,
ISO 17831-2
Amount of fines to be
F2.0 ≤ ≤ 2,0 F4.0 ≤ ≤ 4,0
stated for pellets and for % in mass as
briquettes with shape 9 received
(value to be stated) (value to be stated)
(Figure 2), F, ISO 5370
Amount of fines below
0,5 mm to be stated for
% in mass as
pellets and for briquettes Value to be stated Value to be stated
received
with shape 9 (Figure 2),
F0.5, ISO 5370
Additives ≤ 4 ≤ 5
% in mass as
received
(value to be stated) (value to be stated)
Bulk density, BD, to be
stated for pellets and for kg/m as
BD650 ≥ ≥ 650 BD600 ≥ ≥ 600
briquettes with shape 9 received
(Figure 2), ISO 17828
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ISO/FDIS 17225-8:2022(E)
Net calorific value, Q, MJ/kg as Q20 ≥ 20 Q19 ≥ 19
ISO 18125 received (value to be stated) (value to be stated)
Nitrogen, NMJ, ISO 16948 g/MJ dry N0.26 ≤ ≤ 0,26 N0.53 ≤ ≤ 0,53
Sulfur, S , ISO 16994 g/MJ dry S0.03 ≤ ≤ 0,03 S0.05 ≤ ≤ 0,05
Chlorine, ClMJ, ISO 16994 g/MJ dry Cl0.03 ≤ ≤ 0,03 Cl0.05 ≤ ≤ 0,05
Arsenic, AsMJ, ISO 16968 mg/MJ dry As0.05 ≤ ≤ 0,05 As0.11 ≤ ≤ 0,11
Cadmium, Cd ,
mg/MJ dry Cd0.03 ≤ ≤ 0,03 Cd0.05 ≤ ≤ 0,05
ISO 16968
Chromium, Cr ,
mg/MJ dry Cr0.53 ≤ ≤ 0,53 Cr0.79 ≤ ≤ 0,79
ISO 16968
Copper, CuMJ, ISO 16968 mg/MJ dry Cu0.53 ≤ ≤ 0,53 Cu1.05 ≤ ≤ 1,05
Lead, Pb , ISO 16968 mg/MJ dry Pb0.53 ≤ ≤ 0,53 Pb1.05 ≤ ≤ 1,05
Mercury, HgMJ,
mg/MJ dry Hg0.005 ≤ ≤ 0,005 Hg0.005 ≤ ≤ 0,005
ISO 16968
Nickel, Ni , ISO 16968 mg/MJ dry Ni0.53 ≤ ≤ 0,53 Ni0.53 ≤ ≤ 0,53
Zinc, ZnMJ, ISO 16968 mg/MJ dry Zn5.26 ≤ ≤ 5,26 Zn5.26 ≤ ≤ 5,26
Fixed carbon, C % in mass dry Value to be stated Value to be stated
Informative Total carbon, C,
% in mass dry Value should be stated Value should be stated
ISO 16948
Volatile matter, VM,
% in mass dry Value should be stated Value should be stated
ISO 18123
Ash melting behaviour, SST, DT, HT and FT SST, DT, HT and FT should
ISO 21404 should be stated be stated
Thermally treated
biomass grindability
% in mass Value should be stated Value should be stated
index (TTBGI),
ISO/TS 21596
Water sorption (W )
SORP
and post-immersion
% in mass Values should be stated Values should be stated
durability reduction
(DUR ), ISO 23343-1
Particle density (DE), g/cm³cm as
Value should be stated Value should be stated
ISO 18847 received
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ISO/FDIS 17225-8:2022(E)

Negligible levels of glue, grease and other timber production additives (< 1 % in mass) used in sawmills during

production of timber and timber product from virgin wood are acceptable, if all chemical parameters of the pellets are clearly

within the limits and/or concentrations are too small to be concerned with.
Selected size class D06 or D08 to be stated.

For D06 and D08, the amount of pellets longer than 40 mm may be 1 % in mass. Maximum length shall be ≤ 45 mm.

At the final point of delivery.

Type and amount of additive(s) to aid production, delivery or combustion (e.g. pressing aids, slagging inhibitors or any

other additives such as starch, corn flour, potato flour, vegetable oil or lignin) shall be stated.

Fixed carbon (% in mass dry) is calculated as follows: 100 – (ash [% in mass dry] + volatile matter [% in mass dry]).

Special attention should be paid to the ash melting behaviour for some thermally treated biomass fuels, for example those

produced from eucalyptus, poplar and short rotation coppice. It is recommended that all characteristic temperatures

[shrinkage starting temperature (SST), deformation temperature (DT), hemisphere temperature (HT) and flow temperature

(FT)] are stated in oxidizing conditions. The default ashing temperature according to ISO 21404 is 550 °C ± ± 10 °C. If an

alternative ashing temperature is applied, it shall be specified.
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ISO/FDIS 17225-8:2022(E)

Table 2 — Specification of graded densified biomass fuels produced from thermally processed

chemically untreated and/or chemically treated woody biomass
Master table
Property
Unit TOW1 TOW2
(analysis method)
Normative Origin and source 1.1 Forest, plantation and other virgin wood
(ISO 17225-1:2021, 1.2 By-products and residues from wood
Table 1) processing industry
a, b
1.3 Used wood
Traded form (see
ISO 17225-1:2021, Pellets or briquettes
Table 2)
Dimensions (mm) ISO 17829
Diameter (D) and D06, 6 ± ± 1; D06, 6 ± ± 1;
length (L) of pellets in D08, 8 ± ± 1; D08, 8 ± ± 1;
accordance with Figure 1 D10, 1
...

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 17225-8
ISO/TC 238
Solid biofuels — Fuel specifications
Secretariat: SIS
and classes —
Voting begins on:
2022-12-01
Part 8:
Voting terminates on:
Graded thermally treated and
2023-01-26
densified biomass fuels for
commercial and industrial use
Biocombustibles solides — Classes et spécifications des
combustibles —
Partie 8: Combustibles de biomasses traitées thermiquement et
densifiées en vue d'une utilisation commerciale et industrielle
ISO/CEN PARALLEL PROCESSING
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 17225-8:2022(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. © ISO 2022
---------------------- Page: 1 ----------------------
ISO/FDIS 17225-8:2022(E)
FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 17225-8
ISO/TC 238
Solid biofuels — Fuel specifications
Secretariat: SIS
and classes —
Voting begins on:
Part 8:
Voting terminates on:
Graded thermally treated and
densified biomass fuels for
commercial and industrial use
Biocombustibles solides — Classes et spécifications des
combustibles —
Partie 8: Combustibles de biomasses traitées thermiquement et
densifiées en vue d'une utilisation commerciale et industrielle
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
ISO/CEN PARALLEL PROCESSING

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.
RECIPIENTS OF THIS DRAFT ARE INVITED TO
ISO copyright office
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
CP 401 • Ch. de Blandonnet 8
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
CH-1214 Vernier, Geneva
DOCUMENTATION.
Phone: [phone]
IN ADDITION TO THEIR EVALUATION AS
Reference number
Email: [e-mail]
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 17225-8:2022(E)
Website: www.iso.org
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
Published in Switzerland
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
© ISO 2022 – All rights reserved
NATIONAL REGULATIONS. © ISO 2022
---------------------- Page: 2 ----------------------
ISO/FDIS 17225-8:2022(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction .................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ..................................................................................................................................................................................... 1

3 Terms and definitions .................................................................................................................................................................................... 2

4 Symbols and abbreviated terms..........................................................................................................................................................3

5 Specification of graded pellets and briquettes produced by thermal processing .........................4

Annex A (normative) Template for specification of densified and non-densified biomass

fuels produced by thermal processing ......................................................................................................................................16

Annex B (informative) Reference values for the calculation of the limit values in terms of

energy ...........................................................................................................................................................................................................................18

Bibliography .............................................................................................................................................................................................................................20

iii
© ISO 2022 – All rights reserved
---------------------- Page: 3 ----------------------
ISO/FDIS 17225-8:2022(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 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 first edition cancels and replaces the first edition (ISO/TS 17225-8:2016), which has been

technically revised.
The main changes are as follows:
— raw material basis enlarged;

— Tables 1 to 6 merged into Tables 1 to 3, to be used for pellets and briquettes;

— table for thermally treated woody biomass split in two tables (Table 1 and Table 2);

— threshold values for Tables 1 to 3 stated in terms of energy;
— Annex A introduced to support product specification;

— Annex B introduced to support the calculation of the limit values in terms of energy.

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.
© ISO 2022 – All rights reserved
---------------------- Page: 4 ----------------------
ISO/FDIS 17225-8:2022(E)
Introduction

The objective of this document is to provide unambiguous and clear classification principles for solid

biofuels, to serve as a tool, to enable efficient trading of biofuels, to enable good understanding between

seller and buyer as well as to serve as a tool for communication with equipment manufacturers. It will

also facilitate legal permission procedures and reporting.

This document supports the use of thermally treated and densified biomass in commercial and

industrial energy generation applications and in industrial processes, which require classified quality.

Thermal treatment includes processes such as torrefaction, steam explosion, hydrothermal

carbonization and charring, all of which represent different exposure to heat, oxygen, steam or water.

Thermally treated and densified biomass fuels should only be used in plants with manufacturer

approval.

For individual contracts, ISO 17225-1 can be used. ISO 17225-1 can also be used for specification of

charcoal.

Although this document may be used separately, a general understanding of the standards based on

and supporting ISO 17225-1 is required. It is recommended that ISO 17225-1 is used in conjunction

with this document.
© ISO 2022 – All rights reserved
---------------------- Page: 5 ----------------------
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 17225-8:2022(E)
Solid biofuels — Fuel specifications and classes —
Part 8:
Graded thermally treated and densified biomass fuels for
commercial and industrial use
1 Scope

This document determines the fuel quality classes and specifications of graded densified solid biofuels

produced from thermally treated biomass for commercial use and industrial use. This document covers

pellets and briquettes produced from the following raw materials (see ISO 17225-1:2021, Table 1):

— woody biomass;
— herbaceous biomass;
— fruit biomass;
— aquatic biomass;
— blends and mixtures.
Subcategories of these raw materials are included.

This document does not consider products which are marketed as charcoal or as charcoal products. For

these products, see ISO 17225-1:2021, Table 14.

NOTE Health, safety and environmental issues for solid biofuels are important and need special attention;

however, they are outside the scope of this document.
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 5370, Solid biofuels — Determination of fines content in pellets
ISO 14780, Solid biofuels — Sample preparation
ISO 16559, Solid biofuels — Vocabulary

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 17225-1:2021, Solid biofuels — Fuel specifications and classes — Part 1: General requirements

ISO 17828, Solid biofuels — Determination of bulk density
ISO 17829, Solid Biofuels — Determination of length and diameter of pellets
1) Under preparation. Stage at the time of publication: ISO/DIS 5370:2022.
© ISO 2022 – All rights reserved
---------------------- Page: 6 ----------------------
ISO/FDIS 17225-8:2022(E)

ISO 17831-1, Solid biofuels — Determination of mechanical durability of pellets and briquettes — Part 1:

Pellets

ISO 17831-2, Solid biofuels — Determination of mechanical durability of pellets and briquettes — Part 2:

Briquettes
ISO 18122, Solid biofuels — Determination of ash content
ISO 18125, Solid biofuels — Determination of calorific value

ISO 18134-1, Solid biofuels — Determination of moisture content — Part 1: Reference method

ISO 18134-2, Solid biofuels — Determination of moisture content — Oven dry method — Part 2: Total

moisture — Simplified method
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 and the following 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
pellets made from thermally treated biomass

densified biofuel made from thermally treated solid biomass with or without additives usually with a

cylindrical form, random length typically 5 mm to 40 mm, diameter up to 25 mm and broken ends

EXAMPLE Torrefied biomass, steam exploded biomass, hydrothermally carbonized biomass, charred

biomass.

Note 1 to entry: Drying is not considered as thermal treatment in this definition.

Note 2 to entry: Fuel pellets which are produced by applying the thermal treatment after densification are also

included in this definition.
3.2
briquettes made from thermally treated biomass

densified biofuel made with or without additives in pre-determined geometric form with at least two

dimensions (height width, and length) of more than 25 mm produced by compressing thermally treated

solid biomass

EXAMPLE Torrefied biomass, steam exploded biomass, hydrothermally carbonized biomass, charred

biomass.

Note 1 to entry: Drying is not considered as thermal treatment in this definition.

Note 2 to entry: Fuel briquettes which are produced by applying the thermal treatment after densification are

also included in this definition.
3.3
commercial use

facility that utilizes solid biofuel burning appliances or equipment that have similar fuel requirements

as residential appliances

Note 1 to entry: Commercial applications should not be confused with industrial applications, which can utilize a

much wider array of materials and have vastly different fuel requirements.
© ISO 2022 – All rights reserved
---------------------- Page: 7 ----------------------
ISO/FDIS 17225-8:2022(E)
[SOURCE: ISO 17225-1:2021, 3.2]
3.4
post-immersion durability reduction
DUR

measure of the drop in the durability of thermally treated biomass fuel pellets after immersion in water

Note 1 to entry: A post-immersion durability reduction value of 0 means there was no change to the durability

of the thermally treated pelletized fuel as a result of wetting, whereas, for example, a post-immersion durability

reduction value of 3 indicates that the durability dropped by three percentage points as a result of wetting.

Note 2 to entry: The test procedure is given in ISO 23343-1.

[SOURCE: ISO 23343-1:2021, 3.2, modified — Definition revised and Note 2 to entry added.]

3.5
thermally treated biomass

biomass whose chemical composition has been changed by heat (usually by temperatures of 200 °C to

300 °C and above)
3.6
thermally treated biomass grindability index
TTBGI

measure for the tendency of a fixed volume of thermally treated biomass material to produce fine

particles after grinding under defined settings and conditions
[SOURCE: ISO/TS 21596:2021, 3.3]
3.7
water sorption
SORP

gain or loss of water or moisture by solid biofuels through absorption or adsorption when exposed to

water or varying levels of humidity
[SOURCE: ISO 16559:2022, 3.216]
4 Symbols and abbreviated terms
A designation for ash content on a dry basis [g/MJ dry]
ar as received
BD designation for bulk density as received [kg/m , (loose volume)]
C fixed carbon [% in mass dry]
D designation for diameter as received [mm]
d dry (dry basis)
DT designation for deformation temperature of the fuel ash [°C]
DU designation for mechanical durability as received [% in mass]
DUR designation for post-immersion durability reduction [% in mass]
F designation for amount of fines (<3,15 mm) as received [% in mass]
F0.5 designation for amount of fines below 0,5 mm as received [% in mass]
© ISO 2022 – All rights reserved
---------------------- Page: 8 ----------------------
ISO/FDIS 17225-8:2022(E)
FT designation for flow temperature of the fuel ash [°C]
HT designation for hemisphere temperature of the fuel ash [°C]
L designation for length as received [mm]
M designation for moisture as received on a wet basis, M [% in mass]

Q designation for net calorific value as received, q [MJ/kg, GJ/t, kWh/kg or MWh/t]

p,net,ar
at constant pressure

Q designation for net calorific value on a dry basis, q [MJ/kg or GJ/t or kWh/kg or

d p,net,d
MWh/t] at constant pressure
SST designation for shrinkage starting temperature of the fuel ash [°C]
TTBGI thermally treated biomass grindability index [% in mass]
VM volatile matter on a dry basis [% in mass dry]
W water sorption [% in mass]
SORP

NOTE 1 1 MJ/kg equals 0,2 778 kWh/kg (1 kWh/kg equals 1 MWh/t and 1 MWh/t equals 3,6 MJ/kg). 1 g/cm

equals 1 kg/dm . 1 mg/kg equals 0,000 1 %.

NOTE 2 Designation symbols are used with a number to specify property levels in Tables 1 to 3 and Annex A.

For designation of chemical properties, chemical symbols such as S (sulfur), Cl (chlorine), N (nitrogen) and C

(carbon) are used and the property class is added at the end of the symbol. Values of ash content and chemical

properties (N, S, Cl, As, Cd, Cr, Cu, Pb, Hg, Ni and Zn) are given in g/MJ or mg/MJ, both on a dry basis, with the

index MJ (e.g. S ).
5 Specification of graded pellets and briquettes produced by thermal processing

Property classes of graded densified biomass fuels produced by thermal processing of chemically

untreated woody biomass, chemically untreated and/or chemically treated woody biomass and non-

woody biomass are listed in Tables 1, 2 and 3, respectively. If a densified biomass fuel produced by

thermal processing cannot be classified according to Table 1, 2 or 3, a specification shall be done

according to Annex A.

The specification of pellets made from thermally treated biomass is stated in accordance with Tables 1

to 3 and Figure 1, while briquettes made from thermally treated biomass are specified in accordance

with Tables 1 to 3 and Figure 2. If other traded forms are used, the main dimensions (e.g. height, width,

length) shall be stated.
Key
D diameter
L length
Figure 1 — Dimensions of pellets
© ISO 2022 – All rights reserved
---------------------- Page: 9 ----------------------
ISO/FDIS 17225-8:2022(E)
Key
D diameter
L length
L width
L height
Figure 2 — Shapes and dimensions of briquettes

Sampling and sample preparation shall be done according to ISO 18135 or ISO 21945 and ISO 14780,

respectively. Analyses of the properties shall be carried out in accordance with the appropriate

standard, i.e. ISO 5370, ISO 16948, ISO 16968, ISO 16994, ISO 17828, ISO 17829, ISO 17831-1,

ISO 17831-2, ISO 18122, ISO 18125, ISO 18134-1, and ISO 18134-2. For specification of the origin and

source, ISO 17225-1 shall be applied.

If data for chemical or physical properties are available, further analysis may not be required.

To ensure resources are used appropriately and the declaration is accurate, use the most appropriate

measure as follows:
a) using previous measured values or experience of the same raw material;

b) calculation of properties, for example using typical values and considering generally accepted and

documented specific values;
c) carrying out analysis:
1) with simplified methods, if available;
2) with reference methods.

The responsibility of the producer or supplier to provide correct and accurate information is exactly

the same whether laboratory analysis is performed or not. Typical values do not release the producer or

supplier from providing accurate and reliable information.
© ISO 2022 – All rights reserved
---------------------- Page: 10 ----------------------
ISO/FDIS 17225-8:2022(E)

To assign a fuel to a property class, all properties listed as normative in Table 1, 2 and 3 as well as

Table A1 shall be determined. The determination of properties listed as informative is recommended.

The classes of mechanical, physical and chemical properties shall be stated when leaving the final point

of loading for delivery to the end user. Between the factory gates and the end user, distributors shall

take appropriate measures to maintain the stated level of fines. The quality class according to Table 1,

Table 2, Table 3 or Table A.1 shall be given in the product declaration.

Ash content and concentration of chemical elements N, S, Cl, As, Cd, Cr, Cu, Pb, Hg, Ni and Zn are

influenced by thermal processing and shall be stated in terms of energy with the units g/MJ or mg/MJ

(dry), respectively. To calculate the unit mg/MJ from mg/kg, the concentration of chemical elements

(mg/kg on a dry basis) shall be divided by the net calorific value (Q , MJ/kg on a dry basis). Values in

percentage mass (dry) shall be additionally multiplied by 10 to obtain values in g/MJ (dry). The reference

values used for the calculation of the normative limit values in terms of energy are listed in Annex B.

In any analytical report or product declaration, values shall be stated additionally in terms of mass (in

mg/kg dry or % mass dry). The values shall be rounded individually according to the significant digits

of each property specified in Table 1, 2 and 3.

NOTE 1 For a sample of thermally treated pellets with a lead content of 12 mg/kg dry and a calorific value of

19 MJ/kg dry the resulting value for Pb is 0,63 mg/MJ dry and exceeds the limit value of 0,53 mg/MJ dry for

TW1. A sample with the same lead content of 12 mg/kg dry and a calorific value of 24,5 MJ/kg dry results in a

value of 0,49 mg/MJ dry and fulfils the requirement of class TW1.

NOTE 2 According to ISO 17225-1:2021, Annex D, the net calorific value (at constant pressure) on a dry basis

can be calculated according to Formula (1).
100
qq=+ 0,02443×M × (1)
p,net,dp,net,arar
 
100−M
where

q is the net calorific value (at constant pressure) as received, in megajoules per kilogram

p,net,ar
(MJ/kg);

q is the net calorific value (at constant pressure) in dry matter, in megajoules per kilogram

p,net,d
(MJ/kg);
M is the moisture content as received in % mass;

0,024 43 is the correction factor of the enthalpy of vaporization (constant pressure) for water

(moisture) at 25 °C, in megajoules per kilogram (MJ/kg) per 1 % in mass of moisture.

© ISO 2022 – All rights reserved
---------------------- Page: 11 ----------------------
ISO/FDIS 17225-8:2022(E)

Table 1 — Specification of graded densified biomass fuels produced from thermally processed

chemically untreated woody biomass
Master table
Property
Unit TW1 TW2
(analysis method)
Normative Origin and source 1.1 Forest, plantation and other virgin wood
(ISO 17225-1:2021, 1.2.1 Chemically untreated wood by-products and
Table 1) residues
Traded form (see
ISO 17225-1:2021, Pellets or briquettes
Table 2)
Dimensions (mm) ISO 17829
Diameter (D) and D06, 6 ± 1; D06, 6 ± 1;
length (L) of pellets in mm D08, 8 ± 1; D08, 8 ± 1;
accordance with Figure 1 3,15 ≤ L ≤ 40 3,15 ≤ L ≤ 40
Diameter (D), length (L)
and shape of briquettes
mm Values to be stated
in accordance with
Figure 2
Moisture, M, % in mass as
ISO 18134-1, ISO 18134-2 received, on M08 ≤ 8 M08 ≤ 8
wet basis
Ash, A , ISO 18122 g/MJ dry A0.6 ≤ 0,6 A1.6 ≤ 1,6
Mechanical durability
to be stated for pellets
% in mass as
and for briquettes with DU97.5 ≥ 97,5 DU97.5 ≥ 97,5
received
shape 9 (Figure 2), DU,
ISO 17831-1, ISO 17831-2
Amount of fines to be
F2.0 ≤ 2,0 F4.0 ≤ 4,0
stated for pellets and for % in mass as
briquettes with shape 9 received
(value to be stated) (value to be stated)
(Figure 2), F, ISO 5370
Amount of fines below
0,5 mm to be stated for
% in mass as
pellets and for briquettes Value to be stated Value to be stated
received
with shape 9 (Figure 2),
F0.5, ISO 5370
Additives ≤4 ≤5
% in mass as
received
(value to be stated) (value to be stated)

Negligible levels of glue, grease and other timber production additives (< 1 % in mass) used in sawmills during

production of timber and timber product from virgin wood are acceptable, if all chemical parameters of the pellets are

clearly within the limits and/or concentrations are too small to be concerned with.

Selected size class D06 or D08 to be stated.

For D06 and D08, the amount of pellets longer than 40 mm may be 1 % in mass. Maximum length shall be ≤ 45 mm.

At the final point of delivery.

Type and amount of additive(s) to aid production, delivery or combustion (e.g. pressing aids, slagging inhibitors or any

other additives such as starch, corn flour, potato flour, vegetable oil or lignin) shall be stated.

Fixed carbon (% in mass dry) is calculated as follows: 100 – (ash [% in mass dry] + volatile matter [% in mass dry]).

Special attention should be paid to the ash melting behaviour for some thermally treated biomass fuels, for

example those produced from eucalyptus, poplar and short rotation coppice. It is recommended that all characteristic

temperatures [shrinkage starting temperature (SST), deformation temperature (DT), hemisphere temperature (HT)

and flow temperature (FT)] are stated in oxidizing conditions. The default ashing temperature according to ISO 21404 is

550 °C ± 10 °C. If an alternative ashing temperature is applied, it shall be specified.

© ISO 2022 – All rights reserved
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ISO/FDIS 17225-8:2022(E)
TTaabblle 1 e 1 ((ccoonnttiinnueuedd))
Master table
Property
Unit TW1 TW2
(analysis method)
Bulk density, BD, to be
stated for pellets and for kg/m as re-
BD650 ≥ 650 BD600 ≥ 600
briquettes with shape 9 ceived
(Figure 2), ISO 17828
Net calorific value, Q, MJ/kg as re- Q20 ≥ 20 Q19 ≥ 19
ISO 18125 ceived (value to be stated) (value to be stated)
Nitrogen, N , ISO 16948 g/MJ dry N0.26 ≤ 0,26 N0.53 ≤ 0,53
Sulfur, S , ISO 16994 g/MJ dry S0.03 ≤ 0,03 S0.05 ≤ 0,05
Chlorine, Cl , ISO 16994 g/MJ dry Cl0.03 ≤ 0,03 Cl0.05 ≤ 0,05
Arsenic, As , ISO 16968 mg/MJ dry As0.05 ≤ 0,05 As0.11 ≤ 0,11
Cadmium, Cd ,
mg/MJ dry Cd0.03 ≤ 0,03 Cd0.05 ≤ 0,05
ISO 16968
Chromium, Cr ,
mg/MJ dry Cr0.53 ≤ 0,53 Cr0.79 ≤ 0,79
ISO 16968
Copper, Cu , ISO 16968 mg/MJ dry Cu0.53 ≤ 0,53 Cu1.05 ≤ 1,05
Lead, Pb , ISO 16968 mg/MJ dry Pb0.53 ≤ 0,53 Pb1.05 ≤ 1,05
Mercury, Hg ,
mg/MJ dry Hg0.005 ≤ 0,005 Hg0.005 ≤ 0,005
ISO 16968
Nickel, Ni , ISO 16968 mg/MJ dry Ni0.53 ≤ 0,53 Ni0.53 ≤ 0,53
Zinc, Zn , ISO 16968 mg/MJ dry Zn5.26 ≤ 5,26 Zn5.26 ≤ 5,26
Fixed carbon, C % in mass dry Value to be stated Value to be stated
Informative Total carbon, C,
% in mass dry Value should be stated Value should be stated
ISO 16948
Volatile matter, VM,
% in mass dry Value should be stated Value should be stated
ISO 18123
Ash melting behaviour, SST, DT, HT and FT SST, DT, HT and FT should
ISO 21404 should be stated be stated
Thermally treated bio-
mass grindability index % in mass Value should be stated Value should be stated
(TTBGI), ISO/TS 21596

Negligible levels of glue, grease and other timber production additives (< 1 % in mass) used in sawmills during

production of timber and timber product from virgin wood are acceptable, if all chemical parameters of the pellets are

clearly within the limits and/or concentrations are too small to be concerned with.

Selected size class D06 or D08 to be stated.

For D06 and D08, the amount of pellets longer than 40 mm may be 1 % in mass. Maximum length shall be ≤ 45 mm.

At the final point of delivery.

Type and amount of additive(s) to aid production, delivery or combustion (e.g. pressing aids, slagging inhibitors or any

other additives such as starch, corn flour, potato flour, vegetable oil or lignin) shall be stated.

Fixed carbon (% in mass dry) is calculated as follows: 100 – (ash [% in mass dry] + volatile matter [% in mass dry]).

Special attention should be paid to the ash melting behaviour for some thermally treated biomass fuels, for

example those produced from eucalyptus, poplar and short rotation coppice. It is recommended that all characteristic

temperatures [shrinkage starting temperature (SST), deformation temperature (DT), hemisphere temperature (HT)

and flow temperature (FT)] are stated in oxidizing conditions. The default ashing temperature according to ISO 21404 is

550 °C ± 10 °C. If an alternative ashing temperature is applied, it shall be specified.

© ISO 2022 – All rights reserved
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ISO/FDIS 17225-8:2022(E)
TTaabblle 1 e 1 ((ccoonnttiinnueuedd))
Master table
Property
Unit TW1 TW2
(analysis method)
Water sorption (W )
SORP
and post-immersion
% in mass Values should be stated Values should be stated
durability reduction
(DUR ), ISO 23343-1
Particle density (DE), g/cm as re-
Value should be stated Value should be stated
ISO 18847 ceived

Negligible levels of glue, grease and other timber production additives (< 1 % in mass) used in sawmills during

production of timber and timber product from virgin wood are acceptable, if all chemical parameters of the pellets are

clearly within the limits and/or concentrations are too small to be concerned with.

Selected size class D06 or D08 to be stated.

For D06 and D08, the amount of pellets longer than 40 mm may be 1 % in mass. Maximum length shall be ≤ 45 mm.

At the final point of delivery.
Type and amount of additive(s
...

PROJET
NORME ISO/FDIS
FINAL
INTERNATIONALE 17225-8
ISO/TC 238
Biocombustibles solides — Classes et
Secrétariat: SIS
spécifications des combustibles —
Début de vote:
2022-12-01
Partie 8:
Vote clos le:
Combustibles de biomasses traitées
2023-01-26
thermiquement et densifiées en vue
d'une utilisation commerciale et
industrielle
Solid biofuels — Fuel specifications and classes —
Part 8: Graded thermally treated and densified biomass fuels for
commercial and industrial use
TRAITEMENT PARALLÈLE ISO/CEN
LES DESTINATAIRES DU PRÉSENT PROJET SONT
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ISO/FDIS 17225-8:2022(F)
PROJET
NORME ISO/FDIS
FINAL
INTERNATIONALE 17225-8
ISO/TC 238
Biocombustibles solides — Classes et
Secrétariat: SIS
spécifications des combustibles —
Début de vote:
2022-12-01
Partie 8:
Vote clos le:
Combustibles de biomasses traitées
2023-01-26
thermiquement et densifiées en vue
d'une utilisation commerciale et
industrielle
Solid biofuels — Fuel specifications and classes —
Part 8: Graded thermally treated and densified biomass fuels for
commercial and industrial use
DOCUMENT PROTÉGÉ PAR COPYRIGHT
© ISO 2022
TRAITEMENT PARALLÈLE ISO/CEN

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ISO/FDIS 17225-8:2022(F)
Sommaire Page

Avant-propos .............................................................................................................................................................................................................................iv

Introduction .................................................................................................................................................................................................................................v

1 Domaine d'application ...................................................................................................................................................................................1

2 Références normatives ..................................................................................................................................................................................1

3 Termes et définitions ...................................................................................................................................................................................... 2

4 Symboles et abréviations ............................................................................................................................................................................3

5 Spécification des classes de granulés et de briquettes produites par traitement

thermique ....................................................................................................................................................................................................................4

Annexe A (normative) Modèle de spécification des combustibles de biomasses densifiées

et non densifiées produits par traitement thermique .............................................................................................16

Annexe B (informative) Valeurs de référence pour le calcul des valeurs limites en termes

d'énergie ....................................................................................................................................................................................................................19

Bibliographie ...........................................................................................................................................................................................................................22

iii
© ISO 2022 – Tous droits réservés
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ISO/FDIS 17225-8:2022(F)
Avant-propos

L'ISO (Organisation internationale de normalisation) est une fédération mondiale d'organismes

nationaux de normalisation (comités membres de l'ISO). L'élaboration des Normes internationales est

en général confiée aux comités techniques de l'ISO. Chaque comité membre intéressé par une étude

a le droit de faire partie du comité technique créé à cet effet. Les organisations internationales,

gouvernementales et non gouvernementales, en liaison avec l'ISO participent également aux travaux.

L'ISO collabore étroitement avec la Commission électrotechnique internationale (IEC) en ce qui

concerne la normalisation électrotechnique.

Les procédures utilisées pour élaborer le présent document et celles destinées à sa mise à jour sont

décrites dans les Directives ISO/IEC, Partie 1. Il convient, en particulier de prendre note des différents

critères d'approbation requis pour les différents types de documents ISO. Le présent document

a été rédigé conformément aux règles de rédaction données dans les Directives ISO/IEC, Partie 2

(voir www.iso.org/directives).

L'attention est attirée sur le fait que certains des éléments du présent document peuvent faire l'objet de

droits de propriété intellectuelle ou de droits analogues. L'ISO ne saurait être tenue pour responsable

de ne pas avoir identifié de tels droits de propriété et averti de leur existence. Les détails concernant

les références aux droits de propriété intellectuelle ou autres droits analogues identifiés lors de

l'élaboration du document sont indiqués dans l'Introduction et/ou dans la liste des déclarations de

brevets reçues par l'ISO (voir www.iso.org/brevets).

Les appellations commerciales éventuellement mentionnées dans le présent document sont données

pour information, par souci de commodité, à l'intention des utilisateurs et ne sauraient constituer un

engagement.

Pour une explication de la nature volontaire des normes, la signification des termes et expressions

spécifiques de l'ISO liés à l'évaluation de la conformité, ou pour toute information au sujet de l'adhésion

de l'ISO aux principes de l'Organisation mondiale du commerce (OMC) concernant les obstacles

techniques au commerce (OTC), voir le lien suivant: www.iso.org/iso/fr/avant-propos.html.

Le présent document a été élaboré par le comité technique ISO/TC 238, Biocombustibles solides, en

collaboration avec le comité technique CEN/TC 335, Biocombustibles solides, du Comité européen de

normalisation (CEN), conformément à l'Accord de coopération technique entre l'ISO et le CEN (Accord

de Vienne).

Cette première édition annule et remplace la première édition (ISO/TS 17225-8:2016), qui a fait l'objet

d'une révision technique.
Les principales modifications sont les suivantes:
— la base de matière première a été élargie;

— les Tableaux 1 à 6 ont été fusionnés en Tableaux 1 à 3 à utiliser pour les granulés et les briquettes;

— le tableau pour la biomasse ligneuse traitée thermiquement a été divisé en deux tableaux (Tableau 1

et Tableau 2);
— les valeurs de seuil des Tableaux 1 à 3 ont été établies en termes d'énergie;
— l'Annexe A a été introduite pour étayer les spécifications de produit;

— l'Annexe B a été introduite pour étayer le calcul des valeurs limites en termes d'énergie.

Une liste de toutes les parties de la série ISO 17225 se trouve sur le site web de l'ISO.

Il convient que l'utilisateur adresse tout retour d'information ou toute question concernant le présent

document à l'organisme national de normalisation de son pays. Une liste exhaustive desdits organismes

se trouve à l’adresse www.iso.org/fr/members.html.
© ISO 2022 – Tous droits réservés
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ISO/FDIS 17225-8:2022(F)
Introduction

L'objectif du présent document est de fournir des principes clairs et univoques de classification des

biocombustibles solides, de servir d'outil pour permettre des échanges commerciaux efficaces et

une bonne compréhension entre vendeur et acheteur ainsi que de moyen de communication avec les

fabricants de matériel. Il permettra également de faciliter les procédures d'autorisation légales et

l'établissement de rapports.

Le présent document couvre l'utilisation de combustibles de biomasses traitées thermiquement

et densifiées dans les applications commerciales et industrielles de production d'énergie et dans les

procédés industriels nécessitant des classes de qualité.

Le traitement thermique comprend des procédés tels que la torréfaction, l'explosion de vapeur, la

carbonisation hydrothermale et la carbonisation, tous ces procédés représentant une exposition

différente à la chaleur, à l'oxygène, à la vapeur ou à l'eau. Il convient que les combustibles de biomasses

traitées thermiquement et densifiées ne soient utilisés dans les installations qu'avec l'accord du

fabricant.

Pour des contrats individuels, l'ISO 17225-1 peut être utilisée. L'ISO 17225-1 peut également être

utilisée pour la spécification du charbon de bois.

Bien que le présent document puisse être utilisé séparément, il nécessite une compréhension globale

des normes basées sur l'ISO 17225-1 et de celles qui la complètent. Il est recommandé d'utiliser

l'ISO 17225-1 conjointement au présent document.
© ISO 2022 – Tous droits réservés
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PROJET FINAL DE NORME INTERNATIONALE ISO/FDIS 17225-8:2022(F)
Biocombustibles solides — Classes et spécifications des
combustibles —
Partie 8:
Combustibles de biomasses traitées thermiquement
et densifiées en vue d'une utilisation commerciale et
industrielle
1 Domaine d'application

Le présent document détermine les classes de qualité des combustibles et les spécifications des classes

de biocombustibles solides densifiés produits à partir de biomasses traitées thermiquement en vue

d'une utilisation commerciale et industrielle. Le présent document traite des granulés et des briquettes

produits à partir des matières premières suivantes (voir l'ISO 17225-1:2021, Tableau 1):

— biomasse ligneuse;
— biomasse herbacée;
— biomasse fruitière;
— biomasse aquatique;
— assortiments et mélanges.
Les sous-catégories de ces matières premières sont incluses.

Le présent document ne prend pas en compte les produits commercialisés sous forme de charbon de

bois ou de produits à base de charbon de bois. Pour de tels produits, voir l'ISO 17225-1:2021, Tableau 14.

NOTE Les questions de santé, de sécurité et d'environnement concernant les biocombustibles solides sont

importantes et nécessitent une attention particulière; toutefois, elles ne relèvent pas du domaine d'application

du présent document.
2 Références normatives

Les documents suivants sont cités dans le texte de sorte qu'ils constituent, pour tout ou partie de leur

contenu, des exigences du présent document. Pour les références datées, seule l'édition citée s'applique.

Pour les références non datées, la dernière édition du document de référence s'applique (y compris les

éventuels amendements).

ISO 5370, Biocombustibles solides — Détermination de la teneur en fines des granulés

ISO 14780, Biocombustibles solides — Préparation des échantillons
ISO 16559, Biocombustibles solides — Vocabulaire

ISO 16948, Biocombustibles solides — Détermination de la teneur totale en carbone, hydrogène et azote

ISO 16968, Biocombustibles solides — Détermination des éléments mineurs

ISO 16994, Biocombustibles solides — Détermination de la teneur totale en soufre et en chlore

1) En cours d'élaboration. Stade à la date de publication: ISO/DIS 5370:2022.
© ISO 2022 – Tous droits réservés
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ISO/FDIS 17225-8:2022(F)

ISO 17225-1:2021, Biocombustibles solides — Classes et spécifications des combustibles — Partie 1:

Exigences générales

ISO 17828, Biocombustibles solides — Détermination de la masse volumique apparente

ISO 17829, Biocombustibles solides — Détermination de la longueur et du diamètre des granulés

ISO 17831-1, Biocombustibles solides — Détermination de la résistance mécanique des granulés et des

briquettes — Partie 1: Granulés

ISO 17831-2, Biocombustibles solides — Détermination de la résistance mécanique des granulés et des

briquettes — Partie 2: Briquettes
ISO 18122, Biocombustibles solides — Détermination de la teneur en cendres
ISO 18125, Biocombustibles solides — Détermination du pouvoir calorifique

ISO 18134-1, Biocombustibles solides — Dosage de la teneur en humidité — Partie 1: Méthode de référence

ISO 18134-2, Biocombustibles solides — Dosage de la teneur en humidité — Méthode de séchage à l'étuve

— Partie 2: Humidité totale — Méthode simplifiée
ISO 18135, Biocarburants solides — Échantillonnage

ISO 21945, Biocombustibles solides — Méthode d'échantillonnage simplifiée pour les applications à petite

échelle
3 Termes et définitions

Pour les besoins du présent document, les termes et définitions donnés dans l'ISO 16559 ainsi que les

suivants s'appliquent.

L'ISO et l'IEC tiennent à jour des bases de données terminologiques destinées à être utilisées en

normalisation, consultables aux adresses suivantes:

— ISO Online browsing platform: disponible à l'adresse https:// www .iso .org/ obp

— IEC Electropedia: disponible à l'adresse https:// www .electropedia .org/
3.1
granulés produits à partir de biomasse traitée thermiquement

biocombustible densifié produit à partir de biomasse traitée thermiquement, avec ou sans additifs,

habituellement de forme cylindrique, ayant une longueur aléatoire généralement comprise entre 5 mm

et 40 mm, un diamètre pouvant atteindre 25 mm et des extrémités sectionnées

EXEMPLE Biomasse traitée par torréfaction, biomasse traitée par explosion à la vapeur, biomasse traitée

par carbonisation hydrothermale, biomasse traitée par carbonisation.

Note 1 à l'article: Le séchage n'est pas assimilé à un traitement thermique dans cette définition.

Note 2 à l'article: Les granulés produits par application d'un traitement thermique après compactage sont

également inclus dans cette définition.
3.2
briquettes produites à partir de biomasse traitée thermiquement

biocombustible densifié fabriqué avec ou sans additifs sous une forme géométrique prédéterminée

avec au moins deux dimensions (hauteur, largeur et longueur) de plus de 25 mm, par compression de

biomasse solide traitée thermiquement

EXEMPLE Biomasse traitée par torréfaction, biomasse traitée par explosion à la vapeur, biomasse traitée

par carbonisation hydrothermale, biomasse traitée par carbonisation.

Note 1 à l'article: Le séchage n'est pas assimilé à un traitement thermique dans cette définition.

© ISO 2022 – Tous droits réservés
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ISO/FDIS 17225-8:2022(F)

Note 2 à l'article: Les briquettes produites par application d'un traitement thermique après densification sont

également incluses dans cette définition.
3.3
utilisation commerciale

installation qui utilise des appareils ou des équipements brûlant des biocombustibles solides ayant des

exigences applicables aux combustibles similaires aux appareils domestiques

Note 1 à l'article: Il convient de ne pas confondre les applications commerciales avec les applications industrielles,

qui peuvent utiliser un éventail plus large de matériaux et qui possèdent des exigences relatives aux combustibles

très différentes.
[SOURCE: ISO 17225-1:2021, 3.2]
3.4
réduction de la durabilité après immersion
DUR

mesure de la réduction de durabilité des granulés de combustible de biomasse traitée thermiquement

après immersion dans l'eau

Note 1 à l'article: Une valeur de réduction de la durabilité après immersion de 0 indique que le mouillage n'a pas

influencé la durabilité d'un combustible sous forme de granulés traités thermiquement, tandis qu'une valeur de

réduction de 3 (par exemple) indique que la durabilité a chuté de trois points de pourcentage après le mouillage.

Note 2 à l'article: Le mode opératoire d'essai est décrit dans l'ISO 23343-1.

[SOURCE: ISO 23343‑1:2021, 3.2, modifiée — La définition a été révisée et la note 2 à l'article a été

ajoutée.]
3.5
biomasse traitée thermiquement

biomasse dont la composition chimique a été changée par l'application de chaleur (généralement à des

températures de 200 °C à 300 °C et plus)
3.6
indice de broyabilité de biomasse traitée thermiquement
TTBGI (thermally treated biomass grindability index)

mesure de la tendance d'un volume fixe de matériau de biomasse traitée thermiquement à produire des

particules fines après broyage dans des conditions et réglages définis
[SOURCE: ISO/TS 21596:2021, 3.3]
3.7
sorption d'eau
SORP

gain en eau/humidité par les biocombustibles solides par absorption et/ou adsorption, après exposition

à l'eau ou à différents niveaux d'humidité
[SOURCE: ISO 16559:2022, 3.216]
4 Symboles et abréviations
A désignation de la teneur en cendres sur produit anhydre [g/MJ anhydre]
ar à réception

BD désignation de la masse volumique apparente à réception [kg/m (en volume apparent)] (bulk

density)
C carbone fixe [% en masse, anhydre]
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ISO/FDIS 17225-8:2022(F)
D désignation du diamètre à réception [mm]
d anhydre (sur base sèche) (dry)
DT désignation de la température de déformation des cendres [°C]
DU désignation de la résistance mécanique à réception [% en masse]
DUR désignation de la réduction de la durabilité après immersion [% en masse]
F désignation de la quantité de fines (<3,15 mm) à réception [% en masse]

F0.5 désignation de la quantité de fines inférieures à 0,5 mm, à réception [% en masse]

FT désignation de la température de fluidité des cendres [°C]
HT désignation de la température hémisphérique de fusion des cendres [°C]
L désignation de la longueur à réception [mm]

M désignation de la teneur en humidité à réception sur base humide, M [% en masse]

Q désignation du pouvoir calorifique inférieur à réception, q [MJ/kg ou GJ/t ou kWh/kg ou

p,net,ar
MWh/t] à pression constante

Q désignation du pouvoir calorifique inférieur sur masse anhydre, q [MJ/kg ou GJ/t ou kWh/

d p,net,d
kg ou MWh/t] à pression constante

SST désignation de la température de contraction initiale (température sphérique de fusion) des

cendres [°C] (shrinkage starting temperature)

TTBGI indice de broyabilité de biomasse traitée thermiquement [% en masse] (thermally treated

biomass grindability index)

VM matières volatiles sur produit anhydre [% en masse, anhydre] (volatile matter)

W sorption d'eau [% en masse]
SORP

NOTE 1 1 MJ/kg est égal à 0,277 8 kWh/kg (1 kWh/kg est égal à 1 MWh/t et 1 MWh/t correspond à 3,6 MJ/

3 3
kg). 1 g/cm est égal à 1 kg/dm . 1 mg/kg est égal à 0,000 1 %.

NOTE 2 Les symboles de désignation sont suivis d'un nombre spécifiant le niveau de la propriété dans

les Tableaux 1 à 3 et à l'Annexe A. Les propriétés chimiques sont désignées par les symboles chimiques tels que S

(soufre), Cl (chlore), N (azote), C (carbone) suivis de la classe de propriété. Les valeurs de teneur en cendres et les

propriétés chimiques (N, S, Cl, As, Cd, Cr, Cu, Pb, Hg, Ni et Zn) sont exprimées en unités g/MJ ou mg/MJ, les deux

sur masse anhydre avec l'indice MJ (par exemple: S ).

5 Spécification des classes de granulés et de briquettes produites par traitement

thermique

Les classes de propriété des combustibles de biomasse densifiée produits par traitement thermique

de biomasse ligneuse sans traitement chimique, de biomasse ligneuse sans traitement chimique et/

ou traitée chimiquement, et de biomasse non ligneuse sont énumérées dans les Tableaux 1, 2 et 3,

respectivement. Si un combustible de biomasse densifiée produit par traitement thermique ne peut

être classé conformément au Tableau 1, 2 ou 3, une spécification doit être effectuée conformément à

l'Annexe A.

La spécification des granulés produits à partir de biomasse traitée thermiquement est établie

conformément aux Tableaux 1 à 3 et à la Figure 1, tandis que les briquettes produites à partir de

biomasse traitée thermiquement sont spécifiées conformément aux Tableaux 1 à 3 et à la Figure 2. Si

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ISO/FDIS 17225-8:2022(F)

d'autres formes commercialisées sont utilisées, les dimensions principales (par exemple, hauteur,

largeur, longueur) doivent être indiquées.
Légende
D diamètre
L longueur
Figure 1 — Dimensions des granulés
Légende
D diamètre
L longueur
L largeur
L hauteur
Figure 2 — Formes et dimensions des briquettes

L'échantillonnage et la préparation des échantillons doivent être réalisés conformément à l'ISO 18135

ou à l'ISO 21945 et à l'ISO 14780. L'analyse des propriétés doit être effectuée conformément à la norme

appropriée, c'est-à-dire l'ISO 5370, l'ISO 16948, l'ISO 16968, l'ISO 16994, l'ISO 17828, l'ISO 17829,

l'ISO 17831‑1, l'ISO 17831‑2, l'ISO 18122, l'ISO 18125, l'ISO 18134‑1 et l'ISO 18134‑2. Pour la spécification

de l'origine et de la source, l'ISO 17225-1 doit être appliquée.
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ISO/FDIS 17225-8:2022(F)

Si des données relatives aux propriétés chimiques ou physiques sont disponibles, une analyse

approfondie peut ne pas être requise.

Afin de s'assurer que les ressources sont utilisées de façon appropriée et que la déclaration est précise,

utiliser la mesure la plus appropriée de la manière suivante:

a) l'utilisation de valeurs mesurées précédemment ou de l'expérience avec une même matière

première;

b) le calcul de propriétés, par exemple, en utilisant les valeurs types et en considérant des valeurs

spécifiques, documentées et communément acceptées;
c) la réalisation d'une analyse:
1) avec des méthodes simplifiées, si disponibles;
2) avec des méthodes de référence.

Le producteur ou le fournisseur a toujours la même responsabilité de fournir des informations correctes

et précises, que l'analyse en laboratoire soit réalisée ou non. Les valeurs types ne dispensent pas le

producteur ou le fournisseur de fournir des informations précises et fiables.

Pour attribuer un combustible à une classe de propriété, toutes les propriétés énumérées à titre de

référence normative dans les Tableaux 1, 2 et 3, et dans le Tableau A1 doivent être déterminées. Il est

recommandé de procéder à la détermination des propriétés énumérées à titre informatif. Les classes

de qualité mécanique, physique et chimique doivent être établies au moment de quitter le point final

de chargement pour la livraison à l'utilisateur final. De la sortie de l'usine à l'utilisateur final, les

distributeurs doivent prendre des mesures appropriées pour maintenir le taux de fines indiqué. La

classe de qualité selon le Tableau 1, le Tableau 2, le Tableau 3 ou le Tableau A.1 doit être indiquée dans la

déclaration du produit.

La teneur en cendres ainsi que la concentration des éléments chimiques N, S, Cl, As, Cd, Cr, Cu, Pb, Hg,

Ni et Zn sont influencées par le traitement thermique et doivent être indiquées en termes d'énergie

avec l'unité g/MJ ou mg/MJ (anhydre), respectivement. Pour calculer l'unité mg/MJ à partir de mg/kg,

la concentration des éléments chimiques (mg/kg sur masse anhydre) doit être divisée par le pouvoir

calorifique inférieur (Q , MJ/kg sur masse anhydre). Les valeurs en pourcentage en masse (anhydre)

doivent en outre être multipliées par 10 pour obtenir des valeurs en g/MJ (anhydre). Les valeurs de

référence utilisées pour le calcul des valeurs limites normatives en termes d'énergie sont énumérées

à l'Annexe B. Dans tout rapport d'analyse ou déclaration de produit, les valeurs doivent être également

indiquées en fonction de la masse (en mg/kg anhydre ou en % en masse, anhydre). Les valeurs doivent

être arrondies individuellement en fonction des chiffres significatifs pour chaque propriété énumérée

dans les Tableaux 1, 2 et 3.

NOTE 1 Pour un échantillon de granulés traités thermiquement ayant une teneur en plomb de 12 mg/kg

anhydre et un pouvoir calorifique de 19 MJ/kg anhydre, la valeur résultante pour Pb est de 0,63 mg/MJ anhydre

et dépasse la valeur limite de 0,53 mg/MJ anhydre pour TW1. Un échantillon ayant la même teneur en plomb

de 12 mg/kg anhydre et un pouvoir calorifique de 24,5 MJ/kg anhydre donne une valeur de 0,49 mg/MJ anhydre

et satisfait aux exigences de la classe TW1.

NOTE 2 Selon l'ISO 17225‑1:2021, Annexe D, la valeur du pouvoir calorifique inférieur (à pression constante)

sur masse anhydre peut être calculée à l'aide de la Formule (1).
100
qq=+ 0,02443×M × (1)
p,net,dp,net,arar
 
100−M

q est le pouvoir calorifique inférieur (à pression constante) à réception, exprimé en méga-

p,inf,ar
joules par kilogramme (MJ/kg);
© ISO 2022 – Tous droits réservés
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ISO/FDIS 17225-8:2022(F)

q est le pouvoir calorifique inférieur (à pression constante) sur masse anhydre, exprimé

p,inf,sec
en mégajoules par kilogramme (MJ/kg);
M est la teneur en humidité à réception, exprimée en % en masse;

0,024 43 est le facteur de correction de l'enthalpie de vaporisation (à pression constante) pour

l'eau (humidité) à 25 °C, exprimé en mégajoules par kilogramme (MJ/kg) par 1 % en

masse d'humidité.

Tableau 1 — Spécification des classes de combustibles de biomasses densifiées produits par

traitement thermique de biomasse ligneuse sans traitement chimique
Tableau maître
Propriété
Unité TW1 TW2
(méthode d'analyse)
Normative Origine et source 1.1 Bois de forêt, de plantation et autres bois
(ISO 17225-1:2021, vierges
Tableau 1) 1.2.1 Produits dérivés et sous-produits du bois non
traités chimiquement
Forme commercialisée
(voir l'ISO 17225-1:2021, Granulés ou briquettes
Tableau 2)
Dimensions (mm) ISO 17829
Diamètre (D) et Lon-
D06, 6 ± 1; D06, 6 ± 1;
gueur (L) des granu-
mm D08, 8 ± 1; D08, 8 ± 1;
lés conformément à la
3,15 ≤ L ≤ 40 3,15 ≤ L ≤ 40
Figure 1
Diamètre (D), Longueur
(L) et Forme des bri-
mm Valeurs à indiquer
quettes conformément à
la Figure 2
Humidité, M, % en masse à
ISO 18134-1, ISO 18134-2 réception, sur M08 ≤ 8 M08 ≤ 8
base humide
Cendres, A , ISO 18122 g/MJ anhydre A0.6 ≤ 0,6 A1.6 ≤ 1,6
Résistance mécanique
à indiquer pour les gra-
% en masse à
nulés et les briquettes de DU97.5 ≥ 97,5 DU97.5 ≥ 97,5
réception
forme 9 (Figure 2), DU,
ISO 17831-1, ISO 17831-2
Quantité de fines à indi-
F2.0 ≤ 2,0 F4.0 ≤ 4,0
quer pour les granulés et % en masse à
les briquettes de forme 9 réception
(valeur à indiquer) (valeur à indiquer)
(Figure 2), F, , ISO 5370
Quantité de fines
inférieures à 0,5 mm à
indiquer pour les granu- % en masse à
Valeur à indiquer Valeur à indiquer
lés et les briquettes de réception
forme 9 (Figure 2), F0.5, ,
ISO 5370
Additifs ≤ 4 ≤ 5
% en masse à
réception
(valeur à indiquer) (valeur à indiquer)
Masse volumique appa-
rente, BD, à indiquer
kg/m à récep-
pour les granulés et les BD650 ≥ 650 BD600 ≥ 600
tion
briquettes de forme 9
(Figure 2), ISO 17828
© ISO 2022 – Tous droits réservés
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ISO/FDIS 17225-8:2022(F)
TTabableleaauu 1 1 ((ssuuiitte)e)
Tableau maître
Propriété
Unité TW1 TW2
(méthode d'analyse)
Pouvoir calorifique MJ/kg à récep- Q20 ≥ 20 Q19 ≥ 19
inférieur, Q, , ISO 18125 tion (valeur à mentionner) (valeur à mentionner)
Azote, N , ISO 16948 g/MJ anhydre N0.26 ≤ 0,26 N0.53 ≤ 0,53
Soufre, S , ISO 16994 g/MJ anhydre S0.03 ≤ 0,03 S0.05 ≤ 0,05
Chlore, Cl , ISO 16994 g/MJ anhydre Cl0.03 ≤ 0,03 Cl0.05 ≤ 0,05
Arsenic, As , ISO 16968 mg/MJ anhydre As0.05 ≤ 0,05 As0.11 ≤ 0,11
Cadmium, Cd ,
mg/MJ anhydre Cd0.03 ≤ 0,03 Cd0.05 ≤ 0,05
ISO 16968
Chrome, Cr , ISO 16968 mg/MJ anhydre Cr0.53 ≤ 0,53 Cr0.79 ≤ 0,79
Cuivre, Cu , ISO 16968 mg/MJ anhydre Cu0.53 ≤ 0,53 Cu1.05 ≤ 1,05
Plomb, Pb , ISO 16968 mg/MJ anhydre Pb0.53 ≤ 0,53 Pb1.05 ≤ 1,05
Mercure, Hg ,
mg/MJ anhydre Hg0.005 ≤ 0 005 Hg0.005 ≤ 0 005
ISO 16968
Nickel, Ni , ISO 16968 mg/MJ anhydre Ni0.53 ≤ 0,53 Ni0.53 ≤ 0,53
Zinc, Zn , ISO 16968 mg/MJ anhydre Zn5.26 ≤ 5,26 Zn5.26 ≤ 5,26
Carbone fixe, C % en masse,
Valeur à indiquer Valeur à indiquer
anhydre
...