EN ISO 17225-7:2021 PDF

Overview - EN ISO 17225-7:2021 (Graded non-woody briquettes)

EN ISO 17225-7:2021 is the CEN-adopted part of the ISO 17225 series that specifies fuel quality classes and specifications for graded non-woody briquettes. It covers briquettes produced from non-woody feedstocks: herbaceous biomass, fruit biomass, aquatic biomass, and biomass blends and mixtures. Thermally treated briquettes (e.g., torrefied) are excluded. The document updates and replaces the 2014 edition and aligns requirements with the general rules in ISO 17225‑1:2021.

Key topics and technical requirements

• Fuel quality classes: Defines classification principles and designated property classes for non-woody briquettes to enable clear trading and appliance compatibility.
• Covered materials: Herbaceous, fruit and aquatic biomass, and blends/mixtures (intentionally mixed = blends; unintentionally mixed = mixtures). Chemically treated materials in blends must be declared.
• Measured properties (specified by reference methods): moisture content, net calorific value, ash content, particle density, elemental analysis (C, H, N, S, Cl) and minor elements. Ash melting behaviour is included as an informative property.
• Dimensions and form: Geometric requirements and particle density for briquette types are described (diameter, length).
• Sampling and testing: References to established test standards for sampling, sample preparation and analysis (e.g., ISO 18135, ISO 14780, ISO 18125, ISO 18134 series, ISO 16948/16994/16968).
• Safety and performance considerations: Notes on high ash, chlorine, potassium and silica content typical for non-woody biomass and associated risks (fouling, slagging, corrosion).

Practical applications - who uses this standard

• Biofuel manufacturers and briquette producers - to classify product quality and meet market/product declarations.
• Suppliers, traders and purchasers - to specify and verify fuel quality for contracts.
• Heating appliance and boiler manufacturers - to design equipment compatible with non-woody briquettes and advise users on fuel restrictions.
• Testing laboratories and certification bodies - for compliant sampling and laboratory analysis.
• Regulators and facility managers - to set procurement rules for residential, small commercial, public building and industrial installations where graded non-woody briquettes are used.

Practical guidance in the standard stresses that non-woody briquettes often require specially designed appliances or blending with woody biomass to avoid operational problems and higher emissions.

Related standards

• ISO 17225‑1:2021 (General requirements and origin classification)
• ISO 18135, ISO 18125, ISO 18134 (sampling, calorific value, moisture)
• ISO 16948, ISO 16968, ISO 16994 (elemental and minor element analyses)
• ISO 18847, ISO 14780 (density, sample preparation)

Keywords: EN ISO 17225-7:2021, solid biofuels, non-woody briquettes, fuel specifications, biofuel briquette, biomass blends, fuel quality classes.