Anaerobic degradation of bioplastics: A review

Abstract

Anaerobic digestion (AD) of the organic fraction of municipal solid waste (OFMSW), leading to renewable energy production in the form of methane, is a preferable method for dealing with the increasing amount of waste. Food waste is separated at the source in many countries for anaerobic digestion. However, the presence of plastic bags is a major challenge for such processes. This study investigated the anaerobic degradability of different bioplastics, aiming at potential use as collecting bags for the OFMSW. The chemical composition of the bioplastics and the microbial community structure in the AD process affected the biodegradation of the bioplastics. Some biopolymers can be degraded at hydraulic retention times usually applied at the biogas plants, such as poly(hydroxyalkanoate)s, starch, cellulose and pectin, so no possible contamination would occur. In the future, updated standardization of collecting bags for the OFMSW will be required to meet the requirements of effective operation of a biogas plant.

Keywords: Anaerobic digestion; Biodegradation; Bioplastics; Food waste; Methane; Plastic bags.