Waste wood is a valuable resource, but is hardly recycled despite increasing demand, predicted supply gaps (Mantau et al. 2010), and galloping wood prices since 2020 (Trading Economics 2022). In Germany alone around 10 million tons of waste wood accumulated in 2016. Only a minor part (1.7 million tons) is substantially reused in the production of chipboards. The majority (7.7 million tons) is fed into energy recovery, i.e., burned in one of the 80 German waste wood power plants (BMUV 2021), and is thus lost, while the supply of fresh wood is limited by slow growth cycles and finite acreage. In view of current environmental regulations, climate change and massive tree mortality, waste wood should be kept permanently in the circular economy as a high-quality raw material in the future.
In the context of circular economy, waste wood is an important resource. However,according to the German waste wood ordinance, sorting into four categories is necessary beforerecycling. These categories describe the purity of waste wood based on possible contamination,like paint, foreign bodies, or wood preservatives. Only the purest two categories are allowedto be recycled. For categorization, manual sorting is currently used. This is not only timeconsumingand expensive, but also relatively inaccurate. An automated, sensor-based solutionwould lead to cost savings for recycling companies and also support a sustainable use of resources.For this purpose, a non-contact measuring system, which can examine waste woodchips, will be developed within the project AHOY. As a proof of concept, this paper presents dualenergy X-ray transmission (DE-XRT) for the discrimination between clean wood and the mostcommon contaminants polyvinyl chloride and white lead paint. The results show that even thinlayers of contaminants can be detected. The DE-XRT data are intended for a later fusion withnear-infrared spectroscopy, which is sensitive to organic contaminants hard to detect by DEXRT.Artificial neural networks will be applied to the fused data to achieve a sorting process that yields waste wood chips of the purest two categories.
Copyright: | © Lehrstuhl für Abfallverwertungstechnik und Abfallwirtschaft der Montanuniversität Leoben | |
Quelle: | Recy & Depotech 2022 (November 2022) | |
Seiten: | 6 | |
Preis inkl. MwSt.: | € 3,00 | |
Autor: | R. Wagner Christine Bauer Johannes Leisner | |
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Umweltbildung mit #wirfuerbio
© Witzenhausen-Institut für Abfall, Umwelt und Energie GmbH (4/2023)
#wirfuerbio ist die bundesweite Kampagne der kommunalen Abfallwirtschaft zur Reduzierung von Störstoffen im Bioabfall. Mit einer starken Bandbreite unterschiedlicher crossmedialer Kommunikationsmittel und Maßnahmen verändert sich das Verhalten der Biotonnenbenutzer. Die Störstoffquote sinkt um mehr als 50 Prozent. Die Kampagne weist einen neuen Weg in der Umweltbildung. Mit der Abfallbox und der SpieleApp „#wirfuerbio das Sortierspiel“ wird Kreislaufwirtschaft in Form von Spaß und Spiel erlebbar. Der Beitrag zeigt, wie Abfallbox und Spiele-App didaktisch funktionieren und ein Bewusstsein für Kreislaufwirtschaft und Mülltrennung entwickeln.
Fundamental drying experiments with processed residual municipal solid waste materials
© Lehrstuhl für Abfallverwertungstechnik und Abfallwirtschaft der Montanuniversität Leoben (11/2022)
Waste management companies and municipalities in southwestern Hungary aim the fulfillment of the EU’s target, namely to decrease landfilling below 10 % and increase recycling above 65 % of municipal solid wastes. However selective collection is continuously improved there is still high amount of residual MSW is generated. A new mechanical RMSW processing plant (20 t/h) and an experimental RDF pyrolysis plant (200 kg/h) had been built (Faitli et al. 2020) and now extensive research is being carried out to solve the local utilization of the bio-fraction and the RDF. This is the reason why this fundamental drying research was necessary. Dryer classification and the selection of the best solid waste drying techniques vary significantly due to the vast range of waste to be dried and the inherent challenges of dealing with non-standardized systems. In general, biomass dryers may be categorized according to their heat transmission technique and the physical qualities of wet particles.
Mechanical short-term and long-term properties of PP recyclate blends
© Lehrstuhl für Abfallverwertungstechnik und Abfallwirtschaft der Montanuniversität Leoben (11/2022)
The amount of recycled material in new products should be increased in the next few years. By adding virgin material, the mechanical properties of the pure recyclate can be improved. In this work, 10 % and 40 % post-consumer recyclate was added to a virgin material and analyzed. Both raw materials were also tested. The short-term as well as the long-term properties decrease with increasing recyclate content. The recyclate has a higher influence on the young’s modulus, yield stress and slow crack growth resistance than on the notched impact toughness.
Analysis of different polypropylene waste bales – evaluation of the source
material for polypropylene recycling
© Lehrstuhl für Abfallverwertungstechnik und Abfallwirtschaft der Montanuniversität Leoben (11/2022)
In 2020 Polypropylene (PP) accounted for almost 20% of the plastic consumption in Europe, making it the second most used plastic (Plastics Europe 2021). Due to the high volume of PP used as packaging material (Plastics Europe 2021), large amounts of PP waste are generated every year. Therefore, mechanical recycling of PP waste is a crucial step towards a circular economy. Although there are already some well-established recycling techniques, the lower quality of recyclates compared to virgin materials still poses an obstacle for their use in more demanding applications. Improvements of every step of the whole recycling value chain could solve this problem, with proper and more accurate sorting techniques being particularly crucial.
On the road to 2050: The path to achieving a circular economy for mobility
and renewable energy
© Lehrstuhl für Abfallverwertungstechnik und Abfallwirtschaft der Montanuniversität Leoben (11/2022)
Climate change is one of the biggest crises humanity is facing at this time (Zwane E. M. 2019). Two of the largest emitters of greenhouse gas (GHG) emissions are the mobility (14% of global GHG emissions in 2018) and energy (34%) sector (Lamb et al. 2021), which require a major shift towards renewable energy and alternative fuel systems to succesfully contribute to GHG emission goals (O’Neill et al. 2018). However, this transition comes with its own set of challenges, in particular an increased resource intensity, its dependence on critical minerals and metals, as well as sustainability challenges in the technologies’ supply chains (Mancini & Nuss 2020, Wang et al. 2020). These challenges highlight the need for more sustainable resource management from mining, to consumption, to reuse and recycling, and progress towards a clean and circular economy (Smol et al. 2020).