Suchergebnisse

International audience ; Compostable plastics benefit from a favorable image among the general public, politicians and principals, in particular to selectively collect biowaste. In order to evaluate their behavior in mesophilic methanisation and their contribution to the production of biomethane, the present study compares the anaerobic biodegradability of 10 compostable plastics and 4 paper bags that can be used for the selective collection of biowaste. The results show that compostable plastics have relatively little or no anaerobic biodegradability (0 to 136 mL(CH4)/gVM) or generate an inhibition of the biological process of methanisation. Comparatively, the 4 paper bags tested showed methanogenic potentials of 214 to 313 mL(CH4)/gVM and standard production kinetics. Moreover, the co-digestion of compostable plastics with biowaste seems to promote the anaerobic biodegradability of materials despite a lag phase at the initiation of digestion. Maintaining the physical integrity of compostable plastics after methanisation could present an operational risk related to their accumulation in the digester as well as the generation of (micro) plastics in the digestates. Thus, in industrial context, compostable plastics must be, in the same way as conventional plastics, withdrawn from fermentable organic matter, upstream of digestion, by mechanical pre-treatment of the incoming deposit. ; Les plastiques compostables bénéficient d'une image favorable auprès du grand public, des politiques et des donneurs d'ordre, notamment pour collecter sélectivement les biodéchets. Afin d'évaluer leur comportement en méthanisation mésophile et leur contribution à la production de biométhane, la présente étude compare la biodégradabilité anaérobie de 10 plastiques compostables et de 4 sacs en papier utilisables pour la collecte sélective de biodéchets. Les résultats montrent que les plastiques compostables ont une biodégradabilité anaérobie relativement faible ou nulle (0 à 136 mL(CH4)/gMV) ou génèrent une inhibition du procédé ...