Assessing the sustainability performances of the supply chain of decentralized urban food waste composting for urban green spaces

Abstract

To address challenges of municipal food waste (FW) treatment and urban green space (UGS) soil simultaneously, this study proposes the "Residential FW - Decentralized Composting - Application to UGS" (DCUGS) supply chain and assess its sustainability performances. A Mixed-Integer Linear Programming model integrated with GIS (Geo-Information System) at a fine-scale was set up to simulate this conceptual chain in Haidian, Beijing. The sustainability performance of the supply chain is then assessed across economic, environmental, and social dimensions. The results indicated that compost fulfills 61% of residential and 12% of park green space fertilizer needs, with 51% of FW processed locally. Compared to centralized FW management, DCUGS costs 254.21 CNY/ton, 18.04% of centralized treatment costs, mainly due to reduced transportation. Carbon footprint (CF) analysis indicates DCUGS also achieves a carbon reduction of 64.11 kg CO_2e/ton, surpassing mainstream Chinese FW management. A hedonic model reveals that the increase in residents’ welfare from enhanced greenery outweighs the space occupied by composting facilities. All results show this chain exhibits superior sustainability across three dimensions and may provide a sustainable and preferable choice for the resourceful treatment of FW in Chinese cities.