SESSION F07 / 15 ottobre 2025 / 11:00 - 12:30
Workshop: Biogenic waste in the circular bioeconomy - Potentials and barriers
Chair / Presidente: C. Zafiu (AT)
Biogenic waste represents the largest fraction of municipal solid waste that should be separately collected and used to produce biogas or compost. Composts can be used as a sustainable fertilizer and soil conditioner respectively. However, impurities reduce the quality of composts and must be avoided as much as possible to avoid meet quality criteria of composts and to avoid the contamination in agriculture. Reliable data on the detailed biowaste composition of impurities, biodegradables and food waste is crucial for monitoring and optimizing of corresponding measures. In order to make sorting analyses comparable, a biowaste sorting guideline has been developed in Austria in 2021, which initiated extensive biowaste sorting campaigns. The key findings on the detailed composition and the factors influencing it provide a much clearer picture of the relevance of collection and treatment practices. However, even if impurities can be reduced at any stage of the collection and treatment process the initial collection and avoidance remains the best option to reduce impurities. For the avoidance of impurities it is important to know, which impurities – down to the waste item – were inappropriately disposed of in the separately collected biowaste. In the compost plant, impurities can be removed only partly during pretreatment by different technical solutions, as well as after the composting process. In this workshop we will give a i) comprehensive introduction into methodologies to assess impurities in biowaste and measures which can be applied to reduce it, b) an overview of different composting technologies as well as regulatory thresholds, and c) the general pollution in biowaste and microplastics in composts, as well as a discussion on methods to reduce the pollution.
