Periodic Reporting for period 3 - SUNRISE (MultiSensor sorting tools in a circular economy approach for the efficient recycling of PVB interlayer material in high-quality prodUcts from laminated glass coNstRuction and demolItion waStEs)
Reporting period: 2023-12-01 to 2024-11-30
Polyvinyl butyral (PVB) is used as an interlayer in laminated glass in construction and automotive industries. As recycling PVB presents several difficulties that prevent its reuse as an interlayer, only 9 % is recycled. Laminated glass wastes are recycled by glass recyclers around Europe. While the target in recycling of laminated glasses is to recover the glass, PVB is considered a waste in the glass recycling process. This defines the main objective of SUNRISE to unlock a high quantity of current PVB wastes (>125.000 tons could be recycled) to be reused in high quality applications leading to economic, environmental and social benefits.
The overall objective of SUNRISE is to demonstrate within the glass recycling business, the profit in application of an advanced sorting platform based on an innovative multisensor tool able to provide information from PVB quality in laminated glass wastes, allowing the tailored mechano-chemical treatment for purification of PVB by-product. This will enable the PVB recycling and reusing best quality grades as interlayer film.
The overall objective of SUNRISE is to demonstrate within the glass recycling business, the profit in application of an advanced sorting platform based on an innovative multisensor tool able to provide information from PVB quality in laminated glass wastes, allowing the tailored mechano-chemical treatment for purification of PVB by-product. This will enable the PVB recycling and reusing best quality grades as interlayer film.
In previous periods, WP1 to WP3 were completed and the project reached Milestone 2 with the construction of two multisensor tools. These prototypes allow to classify the laminated glass by different categories separated by the plasticizer type in PVB-based interlayers and quality (in terms of haze and transmittance) of the interlayers. This allows to split the glass wastes before the recycling process and as result has a positive impact on the final quality of the recycled polymer. The tool is based on analysis of the spectroscopic data (NIR, Raman and transmittance) of interlayer and implements a software with developed AI algorithms for classification.
During the last year, demonstration phase of the multisensor and the recycling process itself has been performed completing Milestone 3 and 4 (WP4). In addition, sorted recycled PVB materials obtained from DEMO sites has been processed in different formats in WP5 (pellet, film, dispersion, solutions) and incorporated in applications in WP6. The following results have been achieved:
• Validation of the multisensor operation. More than 1 ton of glass wastes were analysed by multisensor tool and the measurement time was 33 s per waste glass, meaning a sorting capacity of ~109 glasses/hour (equivalent of >25 tons of waste glasses per day). The validation results showed high classification score for type of the interlayer polymer as well as for the main plasticizer (>90%), however, prediction of plasticizer content could be improved. Optical properties including haze were accurately determined allowing to their classification by quality.
• Demonstration of a mechano-chemical treatment for recycling PVB in order to reduce glass content below 0.5 % from automotive and construction wastes (recycling capacity of 544 ton/year). Category 1 (high quality wastes) can be obtained with inorganic contents below 0.3 %.
• A Decision Support Tool (DST) for the optimisation of the recycling steps has been created based on modelling of the mechano-chemical recycling steps. The tool has been validated using process data from the pilot test sites.
• The use of antioxidant has been validated as a closed loop recycling strategy for post consumed PVB wastes. Screening of antioxidants was tested at pilot scale confirming that the selected AOs offered resilience against degradation at reprocessing and protection during the next service life of the material.
• Demonstration of the use of re-PVB in different prototypes. Promising results have been obtained for interlayer use, coatings and batteries (both as binder in electrodes and as separator). On interlayer use, mixtures of virgin and re-PVB have achieved necessary levels of mechanical properties, thermal and humidity resistance. For optical properties, the results are close to the requirements, and the main issue appeared with reprocessing operations and external contaminations affecting the results even when working with reference material.
• LCA analysis confirmed the environmental and health benefits of the new recycling process. Economically, the recycling process has been also assessed and the re-PVB obtained price comparable to market prices.
• Good management practices have been published for glass recycling companies who are looking into recycling the PVB fraction from the laminated glasses.
All the work developed during the project has been actively disseminated. The project has resulted in the definition of 13 KERs, considering not only the solutions developed for recycling but also end uses of re-PVB. Active engagement of stakeholders, including glass recyclers, glass and PVB manufacturers, in the assessment of the project results has been achieved. The standardization of the re-PVB characterization has been published in a new CEN Workshop Agreement CWA 18174 “Plastics — Recycled plastics — Characterization of polyvinyl butyral (PVB) recyclates”. Knowledge generated has resulted in publication of 6 scientific papers.
During the last year, demonstration phase of the multisensor and the recycling process itself has been performed completing Milestone 3 and 4 (WP4). In addition, sorted recycled PVB materials obtained from DEMO sites has been processed in different formats in WP5 (pellet, film, dispersion, solutions) and incorporated in applications in WP6. The following results have been achieved:
• Validation of the multisensor operation. More than 1 ton of glass wastes were analysed by multisensor tool and the measurement time was 33 s per waste glass, meaning a sorting capacity of ~109 glasses/hour (equivalent of >25 tons of waste glasses per day). The validation results showed high classification score for type of the interlayer polymer as well as for the main plasticizer (>90%), however, prediction of plasticizer content could be improved. Optical properties including haze were accurately determined allowing to their classification by quality.
• Demonstration of a mechano-chemical treatment for recycling PVB in order to reduce glass content below 0.5 % from automotive and construction wastes (recycling capacity of 544 ton/year). Category 1 (high quality wastes) can be obtained with inorganic contents below 0.3 %.
• A Decision Support Tool (DST) for the optimisation of the recycling steps has been created based on modelling of the mechano-chemical recycling steps. The tool has been validated using process data from the pilot test sites.
• The use of antioxidant has been validated as a closed loop recycling strategy for post consumed PVB wastes. Screening of antioxidants was tested at pilot scale confirming that the selected AOs offered resilience against degradation at reprocessing and protection during the next service life of the material.
• Demonstration of the use of re-PVB in different prototypes. Promising results have been obtained for interlayer use, coatings and batteries (both as binder in electrodes and as separator). On interlayer use, mixtures of virgin and re-PVB have achieved necessary levels of mechanical properties, thermal and humidity resistance. For optical properties, the results are close to the requirements, and the main issue appeared with reprocessing operations and external contaminations affecting the results even when working with reference material.
• LCA analysis confirmed the environmental and health benefits of the new recycling process. Economically, the recycling process has been also assessed and the re-PVB obtained price comparable to market prices.
• Good management practices have been published for glass recycling companies who are looking into recycling the PVB fraction from the laminated glasses.
All the work developed during the project has been actively disseminated. The project has resulted in the definition of 13 KERs, considering not only the solutions developed for recycling but also end uses of re-PVB. Active engagement of stakeholders, including glass recyclers, glass and PVB manufacturers, in the assessment of the project results has been achieved. The standardization of the re-PVB characterization has been published in a new CEN Workshop Agreement CWA 18174 “Plastics — Recycled plastics — Characterization of polyvinyl butyral (PVB) recyclates”. Knowledge generated has resulted in publication of 6 scientific papers.
SUNRISE project will contribute to unlock a significant volume of plastic waste materials currently unexploited within the EU. The collection of the PVB waste polymers is already within the glass recycling value chain, however this material is considered a waste. According to data from FERVER, only 9 % are recycled. Taking into account the established collection and logistics, the increase in the recycling rate is very dependent on the existence of a technical route, which allows the revalorization of the PVB leading to a benefit increase. The acceptance of SUNRISE solutions by all the recyclers who simply pay a fee by discarding the PVB will be finally translated in an increase in their recycling rate. The project has developed new processes, best practices for recyclers and developed currently non existing standard practices for acceptance of re-PVB materials in the value chain (CWA 18174). LCC calculations have confirmed the economic viability of the recycling process. In addition, several products could enter the market in the short to medium term.
SUNRISE project has demonstrated the potential of post-consumer re-PVB as a raw material for closed loop recycling, which until now is only implemented with pre-consumer wastes. Thanks to the sorting and recycling optimised processes, the requirements for laminated glass applications could be achieved in a short timeframe, this will need using mixtures with virgin materials and ensuring clean and ambient controlled conditions during the steps of re-PVB storage and reprocessing in films. In addition, the activities performed under SUNRISE have generated new knowledge through development of a multisensor tool for in-line classification of the glass wastes, and through the use of re-PVB of lower quality in secondary markets but with a high potential demand, such as coated textiles and batteries. All these achieved innovations will push EU to the forefront in the area of recycling and will promote new jobs and socially innovative solutions. SUNRISE will have a significant positive impact on environment, health and safety. Almost 70% reduction of a carbon footprint for the recycling and reprocessing of re-PVB with respect to current baseline scenarios of landfilling and incineration has been obtained. In addition, the health impacts assessment confirmed a reduction in the influence of these categories by almost 80 %.
SUNRISE project has demonstrated the potential of post-consumer re-PVB as a raw material for closed loop recycling, which until now is only implemented with pre-consumer wastes. Thanks to the sorting and recycling optimised processes, the requirements for laminated glass applications could be achieved in a short timeframe, this will need using mixtures with virgin materials and ensuring clean and ambient controlled conditions during the steps of re-PVB storage and reprocessing in films. In addition, the activities performed under SUNRISE have generated new knowledge through development of a multisensor tool for in-line classification of the glass wastes, and through the use of re-PVB of lower quality in secondary markets but with a high potential demand, such as coated textiles and batteries. All these achieved innovations will push EU to the forefront in the area of recycling and will promote new jobs and socially innovative solutions. SUNRISE will have a significant positive impact on environment, health and safety. Almost 70% reduction of a carbon footprint for the recycling and reprocessing of re-PVB with respect to current baseline scenarios of landfilling and incineration has been obtained. In addition, the health impacts assessment confirmed a reduction in the influence of these categories by almost 80 %.