The recycling of paper and board (PB) yields economic and environmental advantages compared to primary paper production. However, PB from lightweight packaging (LWP) waste is currently not comprehensively reintegrated into the paper value stream. To develop an adapted recycling process for PB from LWP, PB quantities, qualities, and fluctuations ranges in LWP are required. Currently, no sufficient database is available. Therefore, we developed a methodical approach and conducted a case study to access the PB potential in LWP sorting plants using manual analysis and sensor-based material flow monitoring. Differences resulting from seasonal variations, materials from different settlement structures, and fluctuation ranges in LWP composition over two weeks have been investigated. PB contents in the input of 6.5 wt% (ww) and 5.9 wt% (ww) were determined for winter and summer sampling campaigns, respectively. The PB product stream amounted to 5.7 wt% (ww, winter) and 4.8 wt% (ww, summer). Around 45 wt% (ww) of PB from the PB product stream was classified as misplaced by the consumer and should have been discarded in separate paper collections. Based on the determined PB quantities and qualities, a potential of usable and in the PB product stream available PB in LWP was determined. The technically available and usable PB potential in German LWP waste amounts to 89,000 to 100,000tons per year (average PB yield of around 65 wt% (ww)). The methodical approach can be adapted for sorting plant balances. The results can contribute to developing an adapted recycling process for PB from LWP.
Automated quality assurance is gaining popularity across application areas; however, automatization for monitoring and control of product quality in waste processing is still in its infancy. At the same time, research on this topic is scattered, limiting efficient implementation of already developed strategies and technologies across research and application areas. To this end, the current work describes a scoping review conducted to systematically map available sensor-based quality assurance technologies and research based on the PRISMA-ScR framework. Additionally, the current state of research and potential automatization strategies are described in the context of construction and demolition waste processing. The results show 31 different sensor types extracted from a collection of 364 works, which have varied popularity depending on the application. However, visual imaging and spectroscopy sensors in particular seem to be popular overall. Only five works describing quality control system implementation were found, of which three describe varying manufacturing applications. Most works found describe proof-of-concept quality prediction systems on a laboratory scale. Compared to other application areas, works regarding construction and demolition waste processing indicate that the area seems to be especially behind in terms of implementing visual imaging at higher technology readiness levels. Moreover, given the importance of reliable and detailed data on material quality to transform the construction sector into a sustainable one, future research on quality monitoring and control systems could therefore focus on the implementation on higher technology readiness levels and the inclusion of detailed descriptions on how these systems have been verified.