Bio-based recovery of organic carbon from municipal waste streams : Process optimization and microbial community dynamics

Abstract: Resource recovery from waste contributes to the transition to a sustainable society. Municipal organic wastes have enormous potential for resource recovery due to the inherent organic content which makes it possible to obtain bio-based chemicals and bioenergy. In view of this, the focus of the current study was on the bio-based recovery of carbon from municipal organic wastes by exploring process optimization and microbial community dynamics of existing and new technologies for the recovery of bio-based products. The study involved two parts: 1) biogas production through direct anaerobic granule-based treatment of mainstream municipal wastewater; and 2) production of bio-based platform chemicals in the form of volatile fatty acids (VFAs) from sewage sludge and other municipal organic wastes through mixed microbiome co-fermentation. This Ph.D. project demonstrated a waste-to-value approach to shifting wastewater treatment plants to biorefineries for recovering valuable carbon resources through both direct anaerobic treatment of municipal wastewater and co-fermentation of municipal organic waste. The application of VFAs for other processes could lead to a bio-based production platform as an alternative to fossil-based processes.