Assessing the anaerobic degradability and the potential recovery of biomethane from different biodegradable bioplastics in a full-scale approach

[Display omitted] •Full-scale assessment of bioplastics’ anaerobic degradation.•Starch-based and polylactic acid-based bioplastics degrade differently during AD.•AD of polylactid acid-based items produce large amount of biomethane.•Bioplastics’ AD can reduce their leakage into natural environments.•Starch-based shoppers may be degraded by coupled AD and composting. The aim of the present study was to evaluate the anaerobic degradability and the potential recovery of biomethane from different bioplastics using a full-scale approach. Bioplastics were placed inside a real anaerobic digestion plant working under thermophilic conditions and quantitative and qualitative degradation of bioplastics was evaluated. Laboratory-scale experiments were used to determine the amount of biomethane produced by anaerobic degradation of bioplastics. Polylactic acid-based items may degrade completely using retention times compatible with anaerobic digestion plants contributing positively to biomethane production, i.e., in 90 days 397 ± 8 NL CH4 kgvolatile solids-1 were produced by polylactic acid-based cutlery. Starch-based shoppers showed a quick degradation of the starch component in the first month of anaerobic digestion, followed by a slow degradation of the polyester component. Anaerobic digestion and/or anaerobic digestion coupled to digestate composting may represent the best strategy to dispose these wastes meeting the principles of Circular Economy.