An Insight into Post-Consumer Food Waste Characteristics as the Key to an Organic Recycling Method Selection in a Circular Economy

Reducing the phenomenon of food waste and effective management of already wasted food in the form of post-consumer waste, included in the source-separated organic fraction of municipal solid waste (SS-OFMSW) from households and catering facilities, are some of the key challenges of the circular economy (CE), in particular in highly urbanized areas. The basis for the effective use of this waste is the knowledge of its physical and chemical properties. The main objective of the paper is to identify the key technological and organizational parameters for selective collection determining the characteristics of the SS-OFMSW and, consequently, the optimal path for its management. This paper presents the results of qualitative research of SS-OFMSW generated in the capital of Poland-Warsaw-coming from three sources: multi- and single-family housing and catering facilities. The collection efficiency of this waste was determined in the form of quality in container rate (QCR = 92-97%) and variability in terms of impurities and admixtures present in it (CV = 56-87%). High variability indicates that the system of selective waste collection in Warsaw is immature, which may hinder undertaking activities in the field of waste management planning. The study confirmed the suitability of the tested SS-OFMSW for organic recycling, especially using anaerobic digestion (AD), to which it is predisposed by water content, C/N, and biomethane potential (BMP). All tested food waste is characterized by a high yield of biogas in the range of 384-426 m(3)/Mg VS and an average share of methane in biogas at the level of 52-61%. Fertilizer properties, moisture, and its gas potential show little variability (CV <= 16%), which means that these data can be treated as stable data. The obtained results indicate the optimal direction for the collection and processing of SS-OFMSW based on post-consumer food waste in urbanized areas.