M/298 - Solid Biofuels

The proposed international standard describes methods for reducing combined samples (or increments) to laboratory
samples - and laboratory samples to sub-samples and general analysis samples and is applicable to solid biofuels.
The methods described in this proposed document may be used for sample preparation, for example, when the
samples are to be tested for calorific value, moisture content, ash content, bulk density, durability, particle size
distribution, ash melting behaviour, chemical composition, and impurities. The methods are not intended to be
applied to the very large samples required for the testing of bridging properties.

The proposed international standard describes methods for reducing combined samples (or increments) to laboratory
samples - and laboratory samples to sub-samples and general analysis samples and is applicable to solid biofuels.
The methods described in this proposed document may be used for sample preparation, for example, when the
samples are to be tested for calorific value, moisture content, ash content, bulk density, durability, particle size
distribution, ash melting behaviour, chemical composition, and impurities. The methods are not intended to be
applied to the very large samples required for the testing of bridging properties.

The proposed international standard describes methods for reducing combined samples (or increments) to laboratory
samples - and laboratory samples to sub-samples and general analysis samples and is applicable to solid biofuels.
The methods described in this proposed document may be used for sample preparation, for example, when the
samples are to be tested for calorific value, moisture content, ash content, bulk density, durability, particle size
distribution, ash melting behaviour, chemical composition, and impurities. The methods are not intended to be
applied to the very large samples required for the testing of bridging properties.

This International Standard specifies a method for the determination of the gross calorific value of a solid biofuel
at constant volume and at the reference temperature 25 °C in a bomb calorimeter calibrated by combustion of
certified benzoic acid.
The result obtained is the gross calorific value of the analysis sample at constant volume with all the water of
the combustion products as liquid water. In practice, biofuels are burned at constant (atmospheric) pressure
and the water is either not condensed (removed as vapour with the flue gases) or condensed. Under both
conditions, the operative heat of combustion to be used is the net calorific value of the fuel at constant
pressure. The net calorific value at constant volume may also be used; formulas are given for calculating both
values.

This International Standard describes methods for preparing sampling plans and certificates and taking samples of solid biofuels, for example, from the place where the raw materials grow, from production plant, from deliveries e.g. lorry loads, or from stock. It includes both manual and mechanical methods, and is applicable to solid biofuels that are either:
⎯ fine (particle size up to about 10 mm) and regularly-shaped particulate materials that can be sampled
using a scoop or pipe, for example: sawdust, olive stones and wood pellets;
⎯ coarse or irregularly-shaped particulate materials, particle sizes up to about 200 mm that can be sampled
using a fork or shovel, for example: wood chips and nut shells, forest residue chips, and straw;
⎯ baled materials for example: baled straw or grass;
⎯ large pieces (particles sizes above 200 mm) which are either picked manually or automatically;
⎯ vegetable waste, fibrous waste from virgin pulp production and from production of paper from pulp that
has been dewatered;
⎯ round wood.
It may be possible to use this standard on other solid biofuels. The methods described in this
Standard may be used, for example, when the samples are to be tested for moisture content, ash content,
calorific value, bulk density, durability, particle size distribution, ash melting behaviour and chemical
composition. The methods are not intended for obtaining the very large samples required for the testing of bridging properties.

ISO 14780:2017 defines methods for reducing combined samples (or increments) to laboratory samples and laboratory samples to sub-samples and general analysis samples and is applicable to solid biofuels.
The methods defined in this document can be used for sample preparation, for example, when the samples are to be tested for calorific value, moisture content, ash content, bulk density, durability, particle size distribution, ash melting behaviour, chemical composition, and impurities.

ISO 18125:2017 specifies a method for the determination of the gross calorific value of a solid biofuel at constant volume and at the reference temperature 25 °C in a bomb calorimeter calibrated by combustion of certified benzoic acid.
The result obtained is the gross calorific value of the analysis sample at constant volume with all the water of the combustion products as liquid water. In practice, biofuels are burned at constant (atmospheric) pressure and the water is either not condensed (removed as vapour with the flue gases) or condensed. Under both conditions, the operative heat of combustion to be used is the net calorific value of the fuel at constant pressure. The net calorific value at constant volume may also be used; formulae are given for calculating both values.
General principles and procedures for the calibrations and the biofuel experiments are presented in the main text, whereas those pertaining to the use of a particular type of calorimetric instrument are described in Annexes A to C. Annex D contains checklists for performing calibration and fuel experiments using specified types of calorimeters. Annex E gives examples to illustrate some of the calculations.

ISO 18135:2017 describes methods for preparing sampling plans and certificates, as well as taking samples of solid biofuels, for example, from the place where the raw materials grow, from production plant, from deliveries, e.g. lorry loads, or from stock. It includes both manual and mechanical methods, and is applicable to solid biofuels that are either:
- fine (particle sizes up to about 10 mm) and regularly shaped particulate materials that can be sampled using a scoop or pipe, for example, sawdust, olive stones and wood pellets;
- coarse or irregularly shaped particulate materials (particle sizes up to about 200 mm) that can be sampled using a fork or shovel, for example, wood chips and nut shells, forest residue chips, and straw;
- baled materials, for example, baled straw or grass;
- large pieces (particle sizes above 200 mm) that are either picked manually or automatically;
- vegetable waste, fibrous waste from virgin pulp production and from production of paper from pulp that has been dewatered;
- thermally treated and densified biomass materials;
- roundwood.
ISO 18135:2017 is not applicable to airborne dust from solid biofuels. It may be possible to use this document for other solid biofuels.
The methods described in this document may be used, for example, when the samples are to be tested for moisture content, ash content, calorific value, bulk density, durability, particle size distribution, ash melting behaviour and chemical composition.

This document describes the method of determining the total moisture content of a test sample of solid
biofuels by drying in an oven and is used when the highest precision is not needed, e.g. for routine
production control on site. The method described in ISO 18134 (all parts) is applicable to all solid
biofuels. The moisture content of solid biofuels (as received) is always reported based on the total mass
of the test sample (wet basis).

ISO 18134-2:2017 describes the method of determining the total moisture content of a test sample of solid biofuels by drying in an oven and is used when the highest precision is not needed, e.g. for routine production control on site. The method described in ISO 18134 (all parts) is applicable to all solid biofuels. The moisture content of solid biofuels (as received) is always reported based on the total mass of the test sample (wet basis).

This International Standard gives formulae which allow analytical data relating to solid biofuels to
be expressed on the different bases in common use. Consideration is given to corrections that can be
applied to certain determined values for solid biofuels prior to their calculation to other bases.
In Annex A, tools for integrity checks of analytical results are given. In Annex B, conversion factors for
calculation into other units are given. Annex C is a guideline for the use of validation parameters as can
be found in ISO/TC 238 analytical standards.

This International Standard describes methods for the determination of the total sulfur and total
chlorine content in solid biofuels. This International Standard specifies two methods for decomposition
of the fuel and different analytical techniques for the quantification of the elements in the decomposition
solutions. The use of automatic equipment is also included in this International Standard, provided that
a validation is carried out as specified and that the performance characteristics are similar to those of
the method described in this International Standard.

ISO 16994:2016 describes methods for the determination of the total sulfur and total chlorine content in solid biofuels. It specifies two methods for decomposition of the fuel and different analytical techniques for the quantification of the elements in the decomposition solutions. The use of automatic equipment is also included in ISO 16994:2016, provided that a validation is carried out as specified and that the performance characteristics are similar to those of the method described in ISO 16994:2016.

ISO 16993:2016 gives formulae which allow analytical data relating to solid biofuels to be expressed on the different bases in common use. Consideration is given to corrections that can be applied to certain determined values for solid biofuels prior to their calculation to other bases.
In Annex A, tools for integrity checks of analytical results are given. In Annex B, conversion factors for calculation into other units are given. Annex C is a guideline for the use of validation parameters as can be found in ISO/TC 238 analytical standards.

This document aims to define the requirements and method used for testing the mechanical durability of pellets. It is intended for persons and organisations that manufacture, plan, sell, erect or use machinery, equipment, tools and entire plants related to such pellets, and to all persons and organisations involved in producing, purchasing, selling and utilising pellets.
The durability is the measure of the resistance of compressed fuels towards shocks and/or abrasion as a consequence of handling and transportation processes.

This document aims to define the requirements and method used for testing the mechanical durability of briquettes. It is intended for persons and organisations that manufacture, plan, sell, erect or use machinery, equipment, tools and entire plants related to such briquettes, and to all persons and organisations involved in producing, purchasing, selling and utilising briquettes.
The durability is measure of the resistance of densified fuels towards shocks and/or abrasion as a consequence of handling and transportation processes.

This document describes a method of determining bulk density of solid biofuels by the use of a standard measuring container. This method is applicable to all solid biofuels with a nominal top size of maximum 100 mm.
Bulk density is not an absolute value, therefore conditions for its determination have to be standandised in order to gain comparative measuring results.
Note 1: The nominal top size is defined as the aperture size of the sieve where at least 95 % by mass of the material passes (ISO DIS 16559 (14588)).
Note 2: Bulk density of solid biofuels is subject to variation due to several factors such as vibration, shock, pressure, biodegradation, drying and wetting. Measured bulk density can therefore deviate from actual conditions during transportation, storage and transhipment.

ISO 17828:2015 defines a method of determining bulk density of solid biofuels by the use of a standard measuring container. This method is applicable to all pourable solid biofuels with a nominal top size of maximum 100 mm.
Bulk density is not an absolute value; therefore, conditions for its determination have to be standardized in order to gain comparative measuring results.
NOTE Bulk density of solid biofuels is subject to variation due to several factors such as vibration, shock, pressure, biodegradation, drying, and wetting. Measured bulk density can therefore deviate from actual conditions during transportation, storage, or transhipment.

ISO 17831-1:2015 defines a determination method for testing the mechanical durability of pellets. The mechanical durability is a measure of the resistance of compressed fuels towards shocks and/or abrasion as a consequence of handling and transportation.

ISO 17831-2:2015 defines a method for determining the mechanical durability of briquettes. The mechanical durability is a measure of the resistance of compressed fuels towards shocks and/or abrasion as a consequence of handling and transportation.

This document describes the methods for the determination of diameter and length of pellets. Concerning the pellet length methods for both determination of the proportion of oversized pellets and for the determination of the average length are included.

This document specifies a method for the determination of ash content of all solid biofuels.

This document aims to define the requirements and method used to determine the volatile matter content of solid biofuels. It is intended for persons and organisations that manufacture, plan, sell, erect or use machinery, equipment, tools and entire plants related to solid biofuels, and to all persons and organisations involved in producing, purchasing, selling and utilising solid biofuels.
The volatile matter content is determined as the loss in mass, less that due moisture, when solid biofuel is subject to partial pyrolysis under standardized conditions.

ISO 17829:2015 specifies the methods for the determination of diameter and length of pellets. Concerning the pellet length methods for both determination of the proportion of oversized pellets and for determination of the average length are included.

ISO 18123:2015 aims to define the requirements and method used to determine the volatile matter content of solid biofuels. It is intended for persons and organisations that manufacture, plan, sell, erect or use machinery, equipment, tools, and entire plants related to solid biofuels, and to all persons and organisations involved in producing, purchasing, selling, and utilizing solid biofuels.
The volatile matter content is determined as the loss in mass, less that due to moisture, when solid biofuel is subject to partial pyrolysis under standardized conditions.

ISO 18122:2015 specifies a method for the determination of ash content of all solid biofuels.

This document describes the method of determining the total moisture content of a sample of solid biofuels by drying in an oven and should be used when high precision of the determination of moisture content is necessary. The method described in this document is applicable to all solid biofuels.
The total moisture content of biofuels is not an absolute value and conditions for its determination have to be standardised to enable comporative determinations to be made.

This document describes the method of determining the moisture in the analysis sample by drying the sample in an oven. It is intended to be used for general analysis samples according to ISO WD XXXXX (14780). The method described in this document is applicable to all solid biofuels.
Since biofuels in small particle size are very hygroscopic, their moisture content will vary with the change of humidity of the atmosphere and therefore, the moisture of the analyses sample should always be determined simultaneously when portions are weighed out for other analytical determinations, for example calorific value, carbon, nitrogen.

ISO 18134-3:2015 describes the method of determining the moisture in the analysis test sample by drying in an oven. It is intended to be used for general analysis samples in accordance with EN 14780. The method described in this part of ISO 18134-3:2015 is applicable to all solid biofuels. The moisture content of solid biofuels (as received) is always reported based on the total mass of the test sample (wet basis).
Since biofuels in small particle size are very hygroscopic, their moisture content will change with humidity in the atmosphere and therefore, the moisture of the test portion is determined simultaneously with determination of for example calorific value, carbon content, and nitrogen content.
NOTE The term moisture content when used with biomass materials can be misleading since untreated biomass frequently contains varying amounts of volatile compounds (extractives) which can evaporate when determining the moisture content by oven drying (see References [1] and [2]).

ISO 18134-1:2015 describes the method of determining the total moisture content of a test sample of solid biofuels by drying in an oven and may be used when high precision of the determination of moisture content is necessary. The method described in this International Standard is applicable to all solid biofuels. The moisture content of solid biofuels (as received) is always reported based on the total mass of the test sample (wet basis).
NOTE The term moisture content, when used with biomass materials, can be misleading since untreated biomass frequently contains varying amounts of volatile compounds (extractives) which might evaporate when determining moisture content by oven drying (see References [2] and [3]).

This I nternational Standard is intented for the determination of the minor elements As, Ca, Co, Cr, Cu, Hg, Mn, Mo, Ni, Pb, Sb, V and Zn in all solid biofuels. Further it describes methods for sample decomposition and suggests suitable instrumental methods for the determination of the elements of interest in the disgest. The determination of other elements as Se, Ti and Th is also possible with the method described in this International Standard.

This Standard describes a method for the determination of total carbon, hydrogen and nitrogen contents in solid biofuels

This International Standard describes a method for the determination major elements of solid biofuels respectively of their ashes, which are Al, Ca, Fe, Mg, P, K, Na and Tl. The determination of other elements such as Barium (Ba) and manganese (Mn) is also possible with the methods described in this International Standard.

ISO 16968:2015 is intended for the determination of the minor elements Arsenic, Cadmium, Cobalt, Chromium, Copper, Mercury, Manganese, Molybdenum, Nickel, Lead, Antimony, Vanadium, and Zinc in all solid biofuels. Further, it describes methods for sample decomposition and suggests suitable instrumental methods for the determination of the elements of interest in the digests. The determination of other elements such as Selenium, Tin, and Thallium is also possible with the method described in this International Standard.

ISO 16948:2015 describes a method for the determination of total carbon, hydrogen and nitrogen contents in solid biofuels.

ISO 16967:2015 describes methods for the determination of major elements of solid biofuels respectively of their ashes, which are Al, Ca, Fe, Mg, P, K, Si, Na, Ti. The determination of other elements such as barium (Ba) and manganese (Mn) is also possible with the methods described in ISO 16967:2015.
ISO 16967:2015 includes two parts: Part A describes the direct determination on the fuel, this method is also applicable for sulfur and minor elements, Part B gives a method of determination on a prepared 550 °C ash.

This International Standard describes a method for the determination of the water soluble chloride, sodium and potassium content in solid biofuels by extraction with water in a closed container and their following quantification by different analytical techniques.

ISO 16995:2015 describes a method for the determination of the water soluble chloride, sodium and potassium content in solid biofuels by extraction with water in a closed container and their subsequent quantification by different analytical techniques.

This Standard specifies a method for the determination of the size distribution of particulate biofuels by the rotary screen method. The method described is meant for particulate biofuels only, namely materials that either have been reduced in size, such as most wood fuels, or are physically in a particulate form e.g. olive stones, nutshells, grain etc. This Standard applies to particulate uncompressed fuels with a nominal top size of 3,15 mm and over, e.g. wood chips, hog fuel, olive stones etc.

This Technical Report specifies a method for the determination of the size distribution of particulate biofuels by the rotary screen method. The method described is meant for particulate biofuels only, namely materials that either have been reduced in size, such as most wood fuels, or are physically in a particulate form e.g. olive stones, nutshells, grain, etc. This document applies to particulate uncompressed fuels with a nominal top size of 3,15 mm and over, e.g. wood chips, hog fuel, olive stones, etc.

EN ISO 16559 determines the terminology and definitions for solid biofuels. According to the scope of the ISO/TC 238 this standard only includes raw and processed material originating from - forestry and arboriculture, - agriculture and horticulture, - aquaculture Materials originating from different recycling processes of end-of-life-products are not within the scope but relevant terms are included for information. Areas covered by ISO/TC28/SC7 “Liquid biofuels” and ISO/TC193 “Natural gas” are excluded. Other standards with a different scope than this International Standard may have different definitions than this standard.

ISO 16559:2014 determines the terminology and definitions for solid biofuels. According to the scope of the ISO/TC 238 this standard only includes raw and processed material originating from
forestry and arboriculture,
agriculture and horticulture,
aquaculture

EN ISO 17225-5 determines the fuel quality classes and specifications of graded firewood. This part of ISO 17225 covers only firewood produced from the following raw materials (see ISO 17225-1, Table 1): - 1.1.1 Whole trees without roots - 1.1.3 Stem wood - 1.1.4 Logging residues (thick branches, tops etc.) - 1.2.1 Chemically untreated wood residues.

EN ISO 17225-7 determines the fuel quality classes and specifications of graded non-woody briquettes. This part of ISO 17225 covers only non-woody briquettes produced from the following raw materials (see ISO 17225-1, Table 1): - 2 Herbaceous biomass - 3 Fruit biomass - 4 Aquatic biomass - 5 Biomass blends and mixtures. Blends are intentionally mixed biofuels, whereas mixtures are unintentionally mixed biofuels. The origin of the blend and mixture is to be described using ISO 17225-1, Table 1. If solid biofuel blend or mixture contains chemically treated material it shall be stated.

EN ISO 17225-6 determines the fuel quality classes and specifications of graded non-woody pellets. This part of ISO 17225 covers only non-woody pellets produced from the following raw material (see ISO 17225-1, Table 1): - 2 Herbaceous biomass - 3 Fruit biomass - 4 Aquatic biomass - 5 Biomass blends and mixtures. Blends are intentionally mixed biofuels, whereas mixtures are unintentionally mixed biofuels. The origin of the blend and mixture is to be described using ISO 17225-1, Table 1. If solid biofuel blend or mixture contains chemically treated material it shall be stated.

ISO 17225-7:2014 determines the fuel quality classes and specifications of graded non-woody briquettes.

ISO 17225-5:2014 determines the fuel quality classes and specifications of graded firewood.

ISO 17225-6:2014 determines the fuel quality classes and specifications of graded non-woody pellets.

This European Standard defines the procedures to fulfil the quality requirements and describes measures to ensure adequate confidence that the biofuel specification is fulfilled. This European Standard covers the full chain, from supply of raw materials to point of delivery to the end-user. According to the mandate given for the standardization work, the scope of the Technical Committee (TC 335) only includes solid biofuels originating from the following sources:
products from agriculture and forestry; vegetable waste from agriculture and forestry; vegetable waste from the food processing industry; wood waste, with the exception of wood waste which may contain halogenated organic compounds or heavy metals as a result of treatment with wood preservatives or coating, and which includes in particular such wood waste from construction- and demolition waste; cork waste; fibrous vegetable waste from virgin pulp production and from production of paper from pulp, if it is co-incinerated at the place of production and heat generated is recovered.

This European Standard defines the procedures to fulfil the quality requirements and describes measures to ensure adequate confidence that the biofuel specification is fulfilled. This European Standard covers the full chain, from supply of raw materials to point of delivery to the end-user. According to the mandate given for the standardization work, the scope of the Technical Committee (TC 335) only includes solid biofuels originating from the following sources:
products from agriculture and forestry; vegetable waste from agriculture and forestry; vegetable waste from the food processing industry; wood waste, with the exception of wood waste which may contain halogenated organic compounds or heavy metals as a result of treatment with wood preservatives or coating, and which includes in particular such wood waste from construction- and demolition waste; cork waste; fibrous vegetable waste from virgin pulp production and from production of paper from pulp, if it is co-incinerated at the place of production and heat generated is recovered.