Water-energy-waste metabolic integration unlocks co-benefits in China's food processing sector

Resource recovery from wastes presents opportunities for resource conservation and greenhouse gas (GHG) mitigation within food processing sector (FPS). However, complicated by intricate interconnections among water-energy-waste elements, potentials and strategies of their integrated management for achieving co-benefits across the food processing subsectors remain unexplored. This study develops a transformative framework for water-energy-waste metabolic integration within FPS, which transforms linear resource flows into closed-loop cycles. Both baseline scenario (characterizing the prevailing conditions) and foreground scenario (applying the new framework) are formulated to facilitate comparative analyses across 11 subsectors and 31 Chinese provincial regions. The findings demonstrate substantial water-energy-GHGs co-benefits: 40 % reduction in freshwater consumption, 7 % in fossil energy use, and 29 % in GHG emissions nationally. Regions like Shandong and Sichuan, and subsectors such as Meat and Liquor, emerge as major beneficiaries. Wastewater management in most subsectors predominantly drives energy recovery, while subsectors like Oil, Meat, Aquatic Products, and Instant Food benefit primarily from food waste management. Enhanced water reclamation through advanced treatment technologies compromises the energy benefit, especially in regions where subsectors (Sugar, Tabacco) with low organic content wastes prevail. This study provides scalable solutions for optimizing water-energy-waste-GHGs synergies in FPS while highlighting the importance of implementing localized strategies.