oSIST prEN ISO 22075:2026

Solid recovered fuels - Real-time determination of parameters by near-infrared spectroscopy (ISO/DIS 22075:2026)

This document specifies a test method for continuous process analysis (real-time analysis) using near-infrared spectroscopy for the indirect determination of the following fuel-characterising parameters:
—   total chlorine content;
—   water content;
—   heating value.
NOTE   When accuracy is proven, real-time analysis can be supplemented by further fuel-characterising parameters.
This document applies to solid recovered fuels according to ISO 21640.

Feste Sekundärbrennstoffe - Echtzeit-Bestimmung von Parametern mittels Nahinfrarotspektroskopie (ISO/DIS 22075:2026)

Combustibles solides de récupération - Détermination en temps réel des paramètres par spectroscopie dans le proche infrarouge (ISO/DIS 22075:2026)

Trdna alternativna goriva - Določanje parametrov v realnem času z bližnjo infrardečo spektroskopijo (ISO/DIS 22075:2026)

General Information

• Status: Not Published
• Public Enquiry End Date: 01-Jul-2026
• ICS: 75.160.10 - Solid fuels
• Technical Committee: AGO - Refuse derived fuel
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 06-May-2026
• Due Date: 23-Sep-2026
• Ref Project: prEN ISO 22075 - Solid recovered fuels - Real-time determination of parameters by near-infrared spectroscopy (ISO/DIS 22075:2026)

Overview

oSIST prEN ISO 22075:2026:2026: Solid recovered fuels - Real-time determination of parameters by near-infrared spectroscopy is an emerging European and International Standard developed by CEN and ISO (ISO/DIS 22075:2026). This document specifies a continuous, real-time test method utilizing near-infrared (NIR) spectroscopy for the indirect determination of key fuel-characterising parameters in solid recovered fuels (SRF). These parameters include:

• Total chlorine content
• Water (moisture) content
• Heating value (gross and net calorific value)

This standard applies to SRF classified according to ISO 21640, helping the waste-to-fuel and alternative fuels sectors improve analysis efficiency, quality control, and compliance with regulatory frameworks.

Key Topics

• Real-Time Process Analysis: oSIST prEN ISO 22075:2026 outlines methodologies for inline and online analysis, enabling automated and non-destructive monitoring of moving material streams via NIR sensors.
• Fuel-Characterising Parameters: The standard focuses on indirect, continuous measurement of:
  • Total chlorine (on a dry basis): Significant for combustion process optimization and emission control.
  • Moisture content: Essential for assessing SRF quality and combustion performance.
  • Calorific value (gross and net): Determines energy potential for users.
• Material Requirements:
  • Particle size up to 50 mm
  • Layer thickness ≥ 5 cm on the conveyor belt for consistent measurement accuracy
  • Limitation regarding detection of very dark or fine materials due to NIR reflectance properties
• System Implementation:
  • NIR spectroscopy-based sensors and emitters installed above conveyor belts
  • Equipment must comply with environmental operating ranges and IP65 protection class
  • Database adaptation and calibration processes for material-specific accuracy
• Ongoing Calibration and Maintenance:
  • Consistent calibration using laboratory reference methods (EN 15408, ISO 21654, etc.)
  • Procedures for identifying and correcting measurement deviations and errors

Applications

oSIST prEN ISO 22075:2026 finds practical application across industries processing, supplying, or utilizing solid recovered fuels:

• Waste Management & Recycling Facilities: Enables real-time monitoring and quality assurance of SRF derived from municipal waste, industrial residues, and commercial waste streams.
• SRF Production Plants: Facilitates rapid adjustment of production parameters based on moisture, chlorine, and calorific value feedback, minimizing off-spec material and storage needs.
• Combustion and Co-Incineration Plants: Assists operators in optimizing combustion, emission control, and energy output by ensuring consistent feedstock quality.
• Regulatory and Environmental Compliance: Provides a standardized approach aligning with international expectations for fuel quality verification and continuous process control.

By leveraging automated NIR-based systems, organizations benefit from:

• Faster decision-making compared to traditional laboratory analysis
• Enhanced process control with improved safety and reliability
• Reduced operational costs through minimized manual sampling and analysis delays

Related Standards

oSIST prEN ISO 22075:2026 aligns closely with several international standards on solid recovered fuels and analytical procedures:

• ISO 21640: Specifications and classification of solid recovered fuels
• ISO 21645 / ISO 21646: Methods for sampling and sample preparation of SRF
• ISO 21654: Determination of calorific value
• EN 15408: Determination of sulphur, chlorine, fluorine, and bromine content
• EN 60529: Degrees of protection provided by enclosures (IP Code)
• ISO 21637: Vocabulary for solid recovered fuels

These standards together support a comprehensive framework for SRF quality management, from terminology and classification to analytical techniques and real-time monitoring.

---

Keywords: solid recovered fuels, near-infrared spectroscopy, NIR, real-time analysis, fuel characterization, moisture content, chlorine content, calorific value, ISO 22075, process control, SRF, waste-to-energy, quality assurance, CEN standard, continuous monitoring

Standards Content (Sample)

SLOVENSKI STANDARD
01-junij-2026
Trdna alternativna goriva - Določanje parametrov v realnem času z bližnjo
infrardečo spektroskopijo (ISO/DIS 22075:2026)
Solid recovered fuels - Real-time determination of parameters by near-infrared
spectroscopy (ISO/DIS 22075:2026)
Feste Sekundärbrennstoffe - Echtzeit-Bestimmung von Parametern mittels
Nahinfrarotspektroskopie (ISO/DIS 22075:2026)
Combustibles solides de récupération - Détermination en temps réel des paramètres par
spectroscopie dans le proche infrarouge (ISO/DIS 22075:2026)
Ta slovenski standard je istoveten z: prEN ISO 22075
ICS:
75.160.10 Trda goriva Solid fuels
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
International
Standard
ISO/DIS 22075
ISO/TC 300
Solid recovered fuels — Real-time
Secretariat: SFS
determination of parameters by
Voting begins on:
near-infrared spectroscopy
2026-04-29
Combustibles solides de récupération — Détermination en temps
Voting terminates on:
réel de paramètres par spectroscopie dans le proche infrarouge
2026-07-22
ICS: 75.160.10
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS.
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 SUPPORTING DOCUMENTATION.
Reference number
ISO/DIS 22075:2026(en)
DRAFT
ISO/DIS 22075:2026(en)
International
Standard
ISO/DIS 22075
ISO/TC 300
Solid recovered fuels — Real-time
Secretariat: SFS
determination of parameters by
Voting begins on:
near-infrared spectroscopy
Combustibles solides de récupération — Détermination en temps
Voting terminates on:
réel de paramètres par spectroscopie dans le proche infrarouge
ICS: 75.160.10
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2026
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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Published in Switzerland Reference number
ISO/DIS 22075:2026(en)
ii
ISO/DIS 22075:2026(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 4
5 Short description of the measuring principle . 5
6 Material origin and properties . 6
6.1 Origin .6
6.2 Properties .6
7 Implementations of the system . 7
7.1 Real-time analysis system .7
7.1.1 Physical analysis technique .7
7.1.2 Detectors and sensors .7
7.1.3 Lighting system .7
7.1.4 Enclosures/components .8
7.2 Adaptation of the database . .8
7.3 Output of the measured values .8
7.3.1 Total chlorine content .8
7.3.2 Total moisture content .9
7.3.3 Gross calorific value .9
7.3.4 Net calorific value .9
7.4 Installation .9
7.5 Belt speed .9
7.6 Initial commissioning .10
8 Malfunctions and sources of error . 10
9 Calibration of the system .10
9.1 Initial calibration .10
9.1.1 General .10
9.1.2 Sampling and preparation of analysis samples.11
9.1.3 Determination of the analysis values .11
9.1.4 Calculation and storage of the correction factors .11
9.2 Ongoing validation and calibration . 12
Annex A (normative) Determination of the expected values for the database.13
Annex B (informative) Determination of the median . 17
Annex C (informative) Precision data of the method .18
Bibliography .20

iii
ISO/DIS 22075:2026(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO 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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 300 Solid recovered materials, including solid
recovered fuels.
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/DIS 22075:2026(en)
Introduction
To check the specifications of solid recovered fuels, quality controls are usually carried out by both the
manufacturer and the recycler. They are currently mainly carried out through discontinuous chemical-
physical laboratory analyses. Due to the time interval between sampling and the availability of the analysis
results, the fuel quality can only be influenced depending on the analysis results by creating appropriate
temporary storage capacities. In contrast, direct process monitoring and control cannot take place or can
only take place to a limited extent.
Methods based on near-infrared (NIR) spectroscopy enable automated, non-contact, non-destructive and
continuous analysis of the relevant fuel properties in moving material flows. By installing appropriate
analysis equipment above the conveyor belt, the fuel-characterizing parameters of recovered fuels, e.g.
the total chlorine content and the calorific value, can be determined in real time. In addition to analytical
methods, real-time analysis based on near-infrared technology can be used as a supplementary tool for
checking fuel quality but is not currently applicable for solid recovered fuel quality certification.
In order to obtain the most representative and reproducible analysis results possible, uniform framework
conditions are required for the adaptation to the respective material to be examined as well as for the
procedure for the implementation and software adaptation (calibration) of the near-infrared-based real-
time analysis systems. They are described in this document.

v
DRAFT International Standard ISO/DIS 22075:2026(en)
Solid recovered fuels — Real-time determination of
parameters by near-infrared spectroscopy
1 Scope
This document specifies a test method for continuous process analysis (real-time analysis) using near-
infrared spectroscopy for the indirect determination of the following fuel-characterising parameters:
— total chlorine content;
— total moisture content;
— net calorific value.
NOTE When accuracy is proven, real-time analysis can be supplemented by further fuel-characterising
parameters.
This document applies to solid recovered fuels according to ISO 21640.
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.
EN 15408, Solid recovered fuels — Methods for the determination of sulphur (S), chlorine (Cl), fluorine (F) and
bromine (Br) content
EN 15415-1, Solid recovered fuels — Determination of particle size distribution — Part 1: Screen method for
small dimension particles
EN 60529, Degrees of protection provided by enclosures (IP Code)
ISO 21637, Solid recovered fuels — Vocabulary
ISO 21640, Solid recovered fuels — Specifications and classes
ISO 21645, Solid recovered fuels — Methods for sampling
ISO 21646, Solid recovered fuels — Sample preparation
ISO 21654, Solid recovered fuels — Determination of calorific value
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 21637 and ISO 21640 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/

ISO/DIS 22075:2026(en)
3.1
fuel-characterising parameter
parameter which is used to describe the properties of a solid recovered fuel
EXAMPLE Total chlorine content.
3.2
bypass
conveying equipment which is continuously fed with a representative portion of the material flow
EXAMPLE A removal system with a conveyor belt which separates the portion, feeds it to the real-time analysis
system in the secondary flow for analysis and subsequently feeds it back into the main material flow.
3.3
chemometric evaluation
method in which spectra are analysed with the help of multivariate methods following appropriate
preparation
Note 1 to entry: For further information on the chemometric evaluation see reference [1].
3.4
detectable substance group
substance group which, based on their molecular structure, can be detected or measured with the detector
of the real-time analysis system
EXAMPLE Plastics.
3.5
detector
component of the real-time analysis system which converts the electromagnetic radiation generated by the
emitter and then reflected by the particle into electronic signals
Note 1 to entry: The spectrum, the time-dependent amplitude curve and the direction of propagation of the reflected
radiation are characteristically influenced by the respective particle (see also [2]).
Note 2 to entry: Different detector materials can be used in the near infrared (NIR) frequency range (1 100 nm to
2 500 nm). These include e.g. indium gallium arsenide (InGaAs), indium arsenide (InAs) or silicon (Si) (see also [3] and
[4]).
3.6
real-time analysis
automated, continuous and non-destructive method of the process analysis, subdivided into inline analysis
(3.12) and online analysis (3.17)
3.7
emitter
component transmitting electromagnetic radiation onto the particles
EXAMPLE Light source.
Note 1 to entry: Since their maximum radiation intensity is in the NIR range e.g. halogen lamps are used as a light
source (see also [1]).
3.8
expected value
value approached by the mean value with an increasing number of measurements obtained from individual
measurements under the same conditions
3.9
mass per unit area
area-specific mass of a particle
Note 1 to entry: The mass per unit area of a particle can be calculated by dividing the mass by the projection area.

ISO/DIS 22075:2026(en)
3.10
load carrier
substance group which, due to their chemical composition, carries a certain load into the material
EXAMPLE PVC as a load carrier for chlorine.
3.11
identification
process of recognizing the substance group of an analysed particle
Note 1 to entry: In near-infrared spectroscopy, this is done based on electromagnetic radiation reflected by the
particle.
3.12
inline analysis
measurement of material properties in the main flow of the moving commodity to be examined, with the
measuring point located directly in the material flow
3.13
correction factor
numerical factor by which the uncorrected result of a measurement is multiplied to compensate for
systematic error
[SOURCE: ISO 14532:2014, 2.5.1.5, modified — Note 1 to entry has been deleted]
3.14
near-infrared radiation
[1]
electromagnetic radiation in the wave range of near-infrared light (1 000 nm to 2 500 nm)
Note 1 to entry: Further explanations on near-infrared radiation can be taken from literature reference [3].
3.15
near-infrared spectroscopy
physical analysis technology for measuring electromagnetic radiation in the range of near-infrared light
3.16
undetectable components
components which cannot be identified by near-infrared spectroscopy for physical reasons
EXAMPLE Black or very dark coloured materials (carbon coloured, dark grey, black-blue, dark brown etc.) due to
their lack of reflective properties, particles with a particle size of less than 8 mm to 10 mm, composite materials.
3.17
online analysis
analysis, where samples are continuously taken from the running conveyor belt and guided to the real-time
analysis system, e.g. via a bypass
3.18
production batch
defined batch of produced solid recovered fuels with a maximum of 1 500 t per batch
Note 1 to entry: If the mass of a batch is higher than 1 500 t, it shall be divided into two or more batches so that the
batch size remains less than or equal to the maximum batch size.
Note 2 to entry: See also ISO 21645 for more information regarding the “batches”.
3.19
production period
period during which a defined amount of solid recovered fuels is produced

ISO/DIS 22075:2026(en)
3.20
pixel
basic cell area in a 2D image or detector
[SOURCE: ISO 15708-1:2017, 3.1, modified — Note 1 to entry has been deleted]
3.21
process analysis
analysis for the monitoring and control of process flows
EXAMPLE The most common field of application is the quality assurance for the implementation of defined
specifications of an end product in the manufacturing process.
3.22
layer thickness
average thickness of the material transported on the conveyor belt
Note 1 to entry: The layer thickness is determined by the distance between the surface of the conveyor belt and the
surface of the material flow.
3.23
substance group
type of component of a solid recovered fuel
EXAMPLE Possible substance groups are wood, paper, PVC, PE, PS and/or textiles.
3.24
bias
deviation which can be reproduced under the same measurement conditions
3.25
projection area
area of a rather three-dimensional object when projected on to a plane surface at right angles to the direction
of viewing
[SOURCE: EN 12899-2:2007, 3.9, modified — Figure 1 has been deleted]
4 Symbols
For the purposes of this document, the following symbols apply.
A detected projection area, in m
c
measurement value of the real-time analysis
total chlorine content, in % by mass on dry matter basis
c
Cl
analysis value of the laboratory analysis
c
ref
d particle size, in mm
E expected value (e.g. mass per unit area, gross calorific value, chlorine content)
f
correction value
G mass per unit area
j substance group
k Parameter (gross calorific value, chlorine content, total moisture content)

ISO/DIS 22075:2026(en)
total moisture content, in % by mass
M
ad
n number of substance groups
p production batch
t period
gross calorific value (dry basis), in MJ/kg
q
Vg,,rd
net calorific value (as received), in MJ/kg
q
pn,,et ar
5 Short description of the measuring principle
This method applies to the inline and online analysis of moving material flows and can be used to monitor
and control the fuel quality (see Figure 1).
[1]
Figure 1 — Differentiation of the procedures for process analysis
For inline analysis, the measuring point is located directly in the material flow. During an online analysis, a
representative portion is analysed in the bypass.
During an online analysis, a corresponding system for the automatic removal of representative portions
shall also be installed, i.e. the latter shall represent the entire material flow and shall be determined in
accordance with ISO 21645.
By means of near-infrared-based real-time analysis, fuel-characterizing parameters of recovered fuels, e.g.
the total chlorine content and the net calorific value, can be determined automatically and continuously.
The measuring principle is based on the sensor-based identification or recognition and quantification
of detectable substance groups contained in the material flow (e.g. plastics, wood/paper, textiles). The
substance groups are identified by the detection and chemometric evaluation of the electromagnetic
radiation, which, depending on the molecular structure, is characteristically reflected and absorbed by
the materials. Based on this detectable information, individual substance groups can be detected and
differentiated from one another by corresponding comparison spectra. Simultaneously, the specific area
proportions (projection areas) are calculated by the respectively detected pixels. In combination with
empirically collected expected values which are stored for the individual substance groups in the integrated
database of the system (amongst others, average mass per unit area, average substance contents), indirect
determination of the individual parameters can be carried out (see Figure 2). In the case of completely new
material flows it shall be checked, if the database does describe the material sufficiently and otherwise the
database shall be adapted.
ISO/DIS 22075:2026(en)
[8]
Figure 2 — Schematic representation of the real-time analysis system
6 Material origin and properties
6.1 Origin
This document can be applied for solid recovered fuels according to ISO 21637 from the following areas of
origin:
a) high-calorific fractions from municipal waste;
b) sorting residues from various sorting processes;
c) production-specific commercial waste.
6.2 Properties
The material shall have the following properties:
a) The particle size d shall be ≤ 50 mm; the check shall be carried out in accordance with EN 15415-1.
NOTE 1 This test is carried out before the installation of the NIR-Technique. As long as the mechanical
treatment plant has the same configuration (concerning the sieve size of the post shredder) further checks are
not necessary.
b) The layer thickness on the conveyor belt shall be at least 5 cm. It shall be ensured that the conveyor belt
is evenly covered with material and that the composition of the upper layer represents the composition
of the layers below. The layer thickness shall be kept as constant as possible.
c) The proportion of undetectable components shall be as constant as possible.

ISO/DIS 22075:2026(en)
NOTE 2 Near-infrared radiation only penetrates the surface of materials, so underlying layers of material cannot be
detected. The layers below are considered statistically by calibration of the system (see 9.1 and 9.2).
NOTE 3 The optimal material layer can depend on the focus of the NIR-detector used. In principle, an optimum
layer thickness of 5 cm to 7 cm can be assumed. Provided that the composition of the material on the surface is
representative of the entire stream, the layer thickness can be increased further (10 cm to 20 cm). However, this
reduces the proportion of scanned material in relation to the total material.
NOTE 4 The undetectable components usually include black or very dark carbon-coloured materials, particles with
a particle size smaller than 8 mm to 10 mm, composite materials.
NOTE 5 The proportion of undetectables is fundamentally dependent on the material. As long as the proportion
changes only slightly (±5 %), a co
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