Overview
EN ISO 23343-1:2021 (ISO 23343-1:2021) is a CEN-endorsed laboratory method for assessing water sorption and the resulting change in durability of thermally treated biomass pellets. The standard defines how to measure moisture uptake (sorption) after immersion and quantifies post-immersion durability reduction as the difference between the durability of the as-received sample and that of the wetted product. It is intended for pelletized, thermally treated solid biofuels and is not applicable to other densified fuels (e.g., briquettes).
Key topics and requirements
- Scope and purpose: Laboratory determination of water sorption and its effect on pellet durability to support classification and comparative testing.
- Test principle: Measure as-received moisture content and mechanical durability, remove fines by sieving, immerse sub‑samples in water (24 h), drain excess water, then determine post-immersion moisture content and durability.
- Post-immersion durability reduction: Calculated as the numerical difference between initial durability and durability after wetting.
- Apparatus and sample handling:
- Recommended sieve aperture: 3.15 mm (round holes, per ISO 3310-2).
- Recommended sieve diameter: 400 mm (ensure not overloaded).
- Immersion: use water bath and suitable immersion containers (wire mesh sieves are recommended).
- Reference to standard sampling and moisture methods: ISO 18134, ISO 18135, ISO 17831-1, etc.
- Procedure stages: sampling, sieving to remove fines, controlled immersion, moisture and durability tests, calculations and reporting.
- Outputs: Water sorption value, post-immersion durability reduction, and related test report details.
Applications and users
This standard is practical for organizations involved in the production, testing, storage and procurement of pelletized biofuels:
- Pellet manufacturers - quality control, product development and batch verification.
- Laboratories and test houses - standardized laboratory testing for certification and comparative assessment.
- Fuel suppliers and traders - specification compliance and acceptance testing.
- Large energy plants and storage operators - risk assessment for outdoor storage, handling logistics and weather-protection needs.
- Researchers and standards developers - material comparisons and method development for other densified fuels.
By using EN ISO 23343-1:2021, stakeholders can quantify how moisture exposure (e.g., rain during outdoor storage) affects pellet durability and make informed decisions on storage, handling and suitability for specific uses.
Related standards
Relevant normative references included in the document:
Keywords: EN ISO 23343-1:2021, ISO 23343-1:2021, solid biofuels, water sorption, pellet durability, thermally treated biomass, post-immersion durability reduction, pellets testing.