ISO 17831-2:2015

Overview

ISO 17831-2:2015 - Solid biofuels: Determination of mechanical durability of briquettes specifies a laboratory method to quantify the mechanical durability of briquettes. Mechanical durability measures a briquette’s resistance to shocks and abrasion during handling and transportation. The standard defines required apparatus, sample preparation, test procedure, calculation and reporting so manufacturers, testing laboratories and purchasers can compare product robustness in a repeatable way.

Key topics and technical requirements

• Scope and purpose: Determines resistance of densified solid biofuels (briquettes) to impact and abrasion caused by handling and transport.
• Apparatus:
  • Durability drum (briquette tester): cylindrical steel drum (~160 L) with internal length and diameter ≈ 598 ± 8 mm, fitted with a welded rectangular baffle and a dustproof lid; driven at 21 ± 0.1 rpm.
  • Sieve: metal wire-cloth sieve (ISO 3310‑1) with aperture ≈ two‑thirds of briquette diameter but not exceeding 45 mm; sieve diameter ≥ 400 mm.
  • Balance: capacity ≥ 2 kg with 0.1 g readability.
• Sample preparation:
  • Minimum initial sample size ≥ 25 kg (split for moisture and durability testing).
  • Test material is used as received (moisture determined concurrently). Remove fines before testing; cut overlong cylindrical briquettes to length = twice their diameter.
  • Test portion: minimum 2 kg; standard practice uses five replicates (e.g., 5 × 4 kg).
• Procedure:
  • Place prepared test portion in drum and rotate for 5 minutes (≈ 105 rotations).
  • Recover sample and separate fines using the selected sieve with gentle manual shaking (5–10 circular movements) to avoid creating new fines.
• Calculation:
  • Mechanical durability (%) = (mass remaining after drum test ÷ mass before drum test) × 100. Report mean of replicates to 0.1%.
• Reporting and limitations:
  • Report result (as‑received), moisture content, test conditions, briquette shape/dimensions and any unusual observations.
  • Precision (repeatability/reproducibility) statement is not specified due to variability of feedstocks.

Practical applications and users

• Who uses it:
  • Briquette manufacturers and quality control labs for product development and QA.
  • Independent testing laboratories validating product durability claims.
  • Purchasers, distributors and logistics planners to assess handling/transport risk.
  • Equipment and plant designers specifying handling systems and packaging.
• Why it matters:
  • Ensures reliable performance in supply chains, reduces fines generation, improves customer satisfaction and informs specifications for transport and storage.

Related standards

• ISO 17831-1 (pellets)
• ISO 18134 (moisture determination)
• ISO 3310-1 (test sieves)
• ISO 16559 (terminology for solid biofuels)

Keywords: ISO 17831-2:2015, mechanical durability, briquettes, solid biofuels, durability drum, briquette tester, testing procedure, sample preparation, sieve, moisture content.