European glass recycling bodies FERVER and FEVE have welcomed the publication of a new technical report by Stazione Sperimentale del Vetro (SSV), providing robust scientific evidence on the real-world recyclability of opaque glass packaging across Europe.

Commissioned by FEVE and carried out with the operational support of FERVER members, the study evaluates how effectively today’s optical sorting technologies can recognise opaque glass fragments in Cullet Treatment Plants (CTPs). Through a combination of laboratory analysis and industrial-scale trials, the research delivers data-driven insight into the actual performance of Europe’s glass recycling infrastructure.

The findings demonstrate that modern optical sorting systems can reliably identify opaque glass fragments with an average visible light transmittance above 2.5%, measured in line with the opacity protocol currently being finalised by European Committee on Standardisation (CEN), incorporating technical input from CETIE.

This threshold is significantly lower than those defined in some national packaging regulations, which the study shows underestimate current sorting capabilities under real operating conditions.

To ensure statistical robustness, SSV conducted industrial trials at nine CTPs across Europe, processing 2,700 kilograms of standardised cullet from various opaque bottle types. The trials assessed false rejection rates of CSP (ceramics, stones and porcelain) using different optical sorting technologies, providing a representative snapshot of performance across the European recycling landscape.

Due to its technical depth and practical relevance, the study’s conclusions are being taken into account in the development of design-for-recycling specifications for glass packaging now nearing completion within CEN. These guidelines, developed with input from the full value chain, from glass manufacturers and recyclers to fillers, machinery suppliers and EPR schemes, will remain subject to regular review, ensuring they evolve alongside advances in glass design, collection, sorting and recycling technologies.