Overview - ISO 13909-5:2016 (Coke - Sampling from moving streams)
ISO 13909-5:2016 specifies procedures and requirements for designing and establishing mechanical sampling schemes for coke from moving streams. It covers how to plan sampling, choose sampling methods (time-basis, mass-basis, stratified), determine increment mass and sampling intervals, and design and locate mechanical samplers. The standard recognizes the diversity of sampler equipment and does not mandate a single sampler design for all situations.
Key topics and technical requirements
- Establishing a sampling scheme: define quality parameters, lot boundaries, required precision, variability assumptions, and the number of sub-lots and increments (see Clause 4).
- Sampling basis: options include time-basis sampling (fixed time intervals) and mass-basis sampling (fixed mass intervals using belt weighers/mass integrators).
- Increment and sample mass: requirements for minimum sample mass, average increment mass and considerations for nominal top size of coke (Clauses 4.4–4.5).
- Precision and bias: assessment of total variance (sampling, preparation, testing), primary increment variance, and methods to estimate and control precision and bias (Clauses 4.3, 9).
- Methods of sampling: time-basis, stratified random sampling, reference sampling and guidance on sampling intervals and increment extraction (Clause 5).
- Design of mechanical samplers: general design principles, safety, sampling system operation, locating equipment, and specific guidance for falling-stream and cross-belt samplers, including cutter velocity and maintenance (Clause 6).
- Sample handling and preparation: storage, preparation of test samples, and preservation of sample integrity (Clauses 7–8).
- Verification and quality control: procedures to verify sampler performance and minimize bias (Clause 10 and Clause 9).
Practical applications and who uses it
ISO 13909-5:2016 is used by:
- Coke producers and metallurgical plants for process control and product quality verification.
- Quality assurance and laboratory personnel preparing and testing coke samples.
- Plant engineers and sampler designers specifying or retrofitting mechanical samplers (cross-belt, falling-stream).
- Inspection bodies and traders establishing commercial sampling protocols and dispute resolution.
- Regulatory and standards professionals seeking harmonized methods to ensure representative sampling from moving streams.
Benefits include improved measurement precision, reduced sampling bias, consistent commercial quality assessment, and repeatable procedures for continuous handling systems.
Related standards
Keywords: ISO 13909-5, coke sampling, mechanical sampling, sampling from moving streams, time-basis sampling, mass-basis sampling, cross-belt sampler, falling-stream sampler, sampling precision, sampling bias.