Overview
ISO 13605:2018 specifies a wavelength-dispersive X‑ray fluorescence (WDXRF) spectrometric method for the determination of major and minor elements in coal ash, coke ash and boiler ash. The method determines Si, Al, Fe, Ca, Mg, Na, K, Ti, Mn, P and S (reported as oxides where applicable) by preparing fused borate glass discs and measuring element intensities with a WDXRF spectrometer. The procedure is designed to eliminate particle-size effects and to give reliable quantitative results across specified concentration ranges.
Key topics and technical requirements
- Analytes and ranges: Method covers SiO2, Al2O3, Fe2O3, CaO, MgO, Na2O, K2O, TiO2, Mn3O4, P2O5, SO3 with application ranges given in the standard (e.g., SiO2: 5–100 %, Fe2O3: 0.1–25 %, Mn3O4: 0.005–5 %).
- Principle: Fusion of sample with a borate flux to make a homogeneous glass disc (casting or press‑quenching) to minimize matrix/particle effects before WDXRF measurement.
- Calibration and corrections: Use of pure chemicals and/or certified reference materials for calibration; matrix corrections for inter‑element effects; instrumental drift and dead‑time corrections are specified.
- Sample preparation: Ashing per ISO 1171 and sample sizing per ISO 13909‑4/6 or ISO 18283. Boiler ash grinding/drying instructions and disc storage/desiccation procedures are included.
- Apparatus and consumables: Non‑wetting platinum alloy crucibles, non‑wetting moulds (platinum, aluminium or graphite for press‑quench), borate fluxes (lithium tetraborate/ metaborate, lanthanum oxide blends), desiccator, suitable WDXRF spectrometer with vacuum path meeting precision requirements (~0.1 % / 10 counts).
- Quality control: Prepare and analyse a reference material at the start and end of each batch (maximum 25 samples); guidance on fused‑disc quality and crucible cleaning procedures.
- Safety: Standard contains a safety warning - users must establish appropriate lab safety and health practices.
Applications
- Routine quantitative analysis of coal ash and coke ash for combustion, power generation and coke‑making quality control.
- Environmental laboratories monitoring ash composition for disposal or reutilization decisions.
- Industrial R&D and material characterization where reliable major/minor element data in ash matrices are required.
- Regulatory compliance testing and feedstock evaluation for boilers and furnaces.
Who should use this standard
- Analytical and process laboratories in power plants, coke works and coal testing facilities.
- Quality assurance teams in coal and coke producers.
- Environmental and materials testing laboratories using WDXRF for ash characterization.
- Instrument manufacturers and method developers validating calibrations or adding analytes.
Related standards
Keywords: ISO 13605, WDXRF, wavelength dispersive X‑ray fluorescence, coal ash analysis, coke ash, fused glass disc, borate flux, major and minor elements, ash chemistry, calibration, matrix correction.